Week 5, Problem Set Questions:
Question 1
Suppose your company runs a shuttle business of a hotel to and from the local airport. The costs for different customer loads are:
1 customer: $30
2 customers: $32
3 customers: $35
4 customers: $38
5 customers: $42
6 customers: $48
7 customers: $57
8 customers: $68.
What are your marginal costs for each customer load level?
Q
TC
MC
Total Rev
Profit
1
30
10
-20
2
32
2
20
-12
3
35
3
30
-5
4
38
3
40
2
5
42
4
50
8
6
48
6
60
12
7
57
9
70
Question 2
Suppose your company runs a shuttle business of a hotel to and from the local airport. The costs for different customer loads are:
1 customer: $30
2 customers: $32
3 customers: $35
4 customers: $38
5 customers: $42
6 customers: $48
7 customers: $57
8 customers: $68.
If you are compensated $10 per ride, what customer load would you choose?
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MR ≥ MC or you will serve 7 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC < MR or you will serve 10 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC< MR or you will serve 9 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC = MR or you will serve 7 customers.
Question 3
Suppose the number of firms you compete with has recently increased. You estimated that as a result of the increased competition, the demand elasticity has increased from –2 to –3, i.e., you face more elastic demand. You are currently charging $10 for your product. If demand elasticity is -3, you should charge [x].
Question 4
An amusement park, whose customer set is made up of two markets, adults and children, has developed demand schedules as follows:
The marginal operating cost of each unit of quantity is $5. Because marginal cost is a constant, so is average variable cost. Ignore fixed costs. The owners of the amusement part want to maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
14
18
7
13
16
8
12
14
9
11
12
10
10
10
11
9
8
12
8
6
13
7
4
14
6
2
Calculate the price, quantity, and profit if: The amusement park charges a different price in the adult market
Please express your answers for Price and Profit in whole dollars (i.e.10.00)
Please use whole numbers for Quanitity (i.e. 10, 27, 4)
Price
Quantity
Total
Revenue
Marginal
Revenue
Marginal
Cost
Total
Cost
MR-MC
Profit
14
6
84
5
30
34
13
7
91
7
5
35
2
56
12
8
96
5
5
40
0
11
9
99
3
5
45
-2
54
10
10
100
1
5
50
-4
50
9
11
99
-1
5
55
-6
8
12
96
-3
5
60
-8
36
7
13
91
-5
5
65
-10
26
6
14
84
-7
5
70
-12
5
15
75
-9
5
75
-14
0
Q ...
1.Suppose your company runs a shuttle business of a hotel to and.docxchristiandean12115
1.Suppose your company runs a shuttle business of a hotel to and from the local airport. The costs for different customer loads are:
1 customer: $30
2 customers: $32
3 customers: $35
4 customers: $38
5 customers: $42
6 customers: $48
7 customers: $57
8 customers: $68.
What are your marginal costs for each customer load level?
Q
TC
MC
Total Rev
Profit
1
30
10
-20
2
32
20
-12
3
35
30
-5
4
38
40
2
5
42
50
8
6
48
60
12
7
57
70
13
8
68
80
12
B. Suppose your company runs a shuttle business of a hotel to and from the local airport. The costs for different customer loads are:
1 customer: $30
2 customers: $32
3 customers: $35
4 customers: $38
5 customers: $42
6 customers: $48
7 customers: $57
8 customers: $68.
If you are compensated $10 per ride, what customer load would you choose?
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MR ≥ MC or you will serve 7 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC < MR or you will serve 10 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC< MR or you will serve 9 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC = MR or you will serve 7 customers.
C. Suppose the number of firms you compete with has recently increased. You estimated that as a result of the increased competition, the demand elasticity has increased from –2 to –3, i.e., you face more elastic demand. You are currently charging $10 for your product. If demand elasticity is -3, you should charge [x].
D. An amusement park, whose customer set is made up of two markets, adults and children, has developed demand schedules as follows:
The marginal operating cost of each unit of quantity is $5. Because marginal cost is a constant, so is average variable cost. Ignore fixed costs. The owners of the amusement part want to maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
14
18
7
13
16
8
12
14
9
11
12
10
10
10
11
9
8
12
8
6
13
7
4
14
6
2
Calculate the price, quantity, and profit if: The amusement park charges a different price in the adult market
Please express your answers for Price and Profit in whole dollars (i.e.10.00)
Please use whole numbers for Quanitity (i.e. 10, 27, 4)
Price
Quantity
Total
Revenue
Marginal
Revenue
Marginal
Cost
Total
Cost
MR-MC
Profit
6
84
5
30
34
13
91
7
5
35
2
56
12
8
96
5
5
40
0
9
99
3
5
45
-2
54
10
100
1
5
50
-4
50
9
11
99
-1
5
55
-6
12
96
-3
5
60
-8
36
7
91
-5
5
65
-10
26
6
14
84
-7
5
70
-12
5
15
75
-9
5
75
-14
0
E. An amusement park, whose customer set is made up of two markets,.
Running head GOVERNMENT 1GOVERNMENT 7Question 1Supp.docxwlynn1
Running head: GOVERNMENT 1
GOVERNMENT 7
Question 1
Suppose the number of firms you compete with has recently increased. You estimated that as a result of the increased competition, the demand elasticity has increased from
–
2 to
–
3, i.e., you face more elastic demand. You are currently charging $10 for your product. If demand elasticity is -3, you should charge [x].
Question 2
An amusement park, whose customer set is made up of two markets, adults and children, has developed demand schedules as follows:
The marginal operating cost of each unit of quantity is $5. Because marginal cost is a constant, so is average variable cost. Ignore fixed costs. The owners of the amusement part want to maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
14
18
7
13
16
8
12
14
9
11
12
10
10
10
11
9
8
12
8
6
13
7
4
14
6
2
Calculate the price, quantity, and profit if: The amusement park charges a different price in the adult market
Please express your answers for Price and Profit in whole dollars (i.e.10.00)
Please use whole numbers for Quanitity (i.e. 10, 27, 4)
Price
Quantity
Total Revenue
Marginal Revenue
Marginal Cost
Total Cost
MR-MC
Profit
84
5.00
30.00
54.00
91
7.00
5.00
35.00
2.00
96
5.00
5.00
40.00
0.00
99
3.00
5.00
45.00
-2.00
100
1.00
5.00
50.00
-4.00
99
-1.00
5.00
55.00
-6.00
96
-3.00
5.00
60.00
-8.00
91
-5.00
5.00
65.00
-10.00
84
-7.00
5.00
70.00
-12.00
75
-9.00
5.00
75.00
-14.00
Question 3
An amusement park, whose customer set is made up of two markets, adults and children, has developed demand schedules as follows:
The marginal operating cost of each unit of quantity is $5. Because marginal cost is a constant, so is average variable cost. Ignore fixed costs. The owners of the amusement part want to maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
14
18
7
13
16
8
12
14
9
11
12
10
10
10
11
9
8
12
8
6
13
7
4
14
6
2
Calculate the price, quantity, and profit if: The amusement park charges a different price in the child's market
Please express your answers for Price and Profit in whole dollars (i.e.10.00)
Please use whole numbers for Quanitity (i.e. 10, 27, 4)
Price
Quantity
Total Revenue
Marginal Revenue
Marginal Cost
Total Cost
MR-MC
Profit
Blank 1
Blank 2
52
5.00
20.00
Blank 3
Blank 4
Blank 5
72
10.00
5.00
30.00
5.00
Blank 6
Blank 7
Blank 8
88
8.00
5.00
40.00
3.00
Blank 9
Blank 10
Blank 11
100
6.00
5.00
50.00
1.00
Blank 12
Blank 13
Blank 14
108
4.00
5.00
60.00
-1.00
Blank 15
Blank 16
Blank 17
112
2.00
5.00
70.00
-3.00
Blank 18
Blank 19
Blank 20
112
0.00
5.00
80.00
-5.00
Blank 21
Blank 22
Blank 23
108
-2.00
5.00
90.00
-7.00
Blank 24
Blank 25
Blank 26
100
-4.00
5.00
100.00
-9.00
Blank 27
Blank 28
Blank 29
88
-6.00
5.00
110.00
-11.00
Blank 30
Question 4
The marginal operating cost of each unit of.
Many people are relatively healthy and have low annual medical cos.docxinfantsuk
Many people are relatively healthy and have low annual medical costs but for some the costs can be extremely high. health economists often model medical costs using the log normal distribution. assuming medical costs are distributed LN (8,3) what is the probability a person pays less than $3,000 in health care in a single year.
Week 4 Practice Worksheet
PSY/315 Version 6
4
Prepare a written response to the following questions.
Chapters 9 &11
1. Two boats, the Prada (Italy) and the Oracle (USA), are competing for a spot in the upcoming America’s Cup race. They race over a part of the course several times. The sample times in minutes for the Prada were: 12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 14.2, and 11.3. The sample times in minutes for the Oracle were: 14.1, 14.1, 14.2, 17.4, 15.8, 16.7, 16.1, 13.3, 13.4, 13.6, 10.8, and 19.0. For data analysis, the appropriate test is the t-Test: Two-Sample Assuming Unequal Variances.
The next table shows the results of this independent t-test. At the .05 significance level, can we conclude that there is a difference in their mean times? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Prada
Oracle
12.170
14.875
mean
1.056
2.208
std. dev.
10
12
n
16
df
-2.7050
difference (Prada - Oracle)
0.7196
standard error of difference
0
hypothesized difference
-3.76
t
.0017
p-value (two-tailed)
-4.2304
confidence interval 95.% lower
-1.1796
confidence interval 95.% upper
1.5254
margin of error
2. The Willow Run Outlet Mall has two Haggar Outlet Stores, one located on Peach Street and the other on Plum Street. The two stores are laid out differently, but both store managers claim their layout maximizes the amounts customers will purchase on impulse. A sample of ten customers at the Peach Street store revealed they spent the following amounts more than planned: $17.58, $19.73, $12.61, $17.79, $16.22, $15.82, $15.40, $15.86, $11.82, $15.85. A sample of fourteen customers at the Plum Street store revealed they spent the following amounts more than they planned when they entered the store: $18.19, $20.22, $17.38, $17.96, $23.92, $15.87, $16.47, $15.96, $16.79, $16.74, $21.40, $20.57, $19.79, $14.83. For Data Analysis, a t-Test: Two-Sample Assuming Unequal Variances was used.
At the .01 significance level is there a difference in the mean amount purchased on an impulse at the two stores? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Peach Street
Plum Street
15.8680
18.2921
mean
2.3306
2.5527
std. dev.
10
14
n
20
df
-2.42414
difference (Peach Str ...
TitleABC123 Version X1Week 4 Practice Worksheet.docxedwardmarivel
Title
ABC/123 Version X
1
Week 4 Practice Worksheet
PSY/315 Version 6
1
University of Phoenix MaterialWeek 4 Practice Worksheet
Prepare a written response to the following questions.
Chapters 9 &11
1. Two boats, the Prada (Italy) and the Oracle (USA), are competing for a spot in the upcoming America’s Cup race. They race over a part of the course several times. The sample times in minutes for the Prada were: 12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 14.2, and 11.3. The sample times in minutes for the Oracle were: 14.1, 14.1, 14.2, 17.4, 15.8, 16.7, 16.1, 13.3, 13.4, 13.6, 10.8, and 19.0. For data analysis, the appropriate test is the t-Test: Two-Sample Assuming Unequal Variances.
The next table shows the results of this independent t-test. At the .05 significance level, can we conclude that there is a difference in their mean times? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Prada
Oracle
12.170
14.875
mean
1.056
2.208
std. dev.
10
12
n
16
df
-2.7050
difference (Prada - Oracle)
0.7196
standard error of difference
0
hypothesized difference
-3.76
t
.0017
p-value (two-tailed)
-4.2304
confidence interval 95.% lower
-1.1796
confidence interval 95.% upper
1.5254
margin of error
2. The Willow Run Outlet Mall has two Haggar Outlet Stores, one located on Peach Street and the other on Plum Street. The two stores are laid out differently, but both store managers claim their layout maximizes the amounts customers will purchase on impulse. A sample of ten customers at the Peach Street store revealed they spent the following amounts more than planned: $17.58, $19.73, $12.61, $17.79, $16.22, $15.82, $15.40, $15.86, $11.82, $15.85. A sample of fourteen customers at the Plum Street store revealed they spent the following amounts more than they planned when they entered the store: $18.19, $20.22, $17.38, $17.96, $23.92, $15.87, $16.47, $15.96, $16.79, $16.74, $21.40, $20.57, $19.79, $14.83. For Data Analysis, a t-Test: Two-Sample Assuming Unequal Variances was used.
At the .01 significance level is there a difference in the mean amount purchased on an impulse at the two stores? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Peach Street
Plum Street
15.8680
18.2921
mean
2.3306
2.5527
std. dev.
10
14
n
20
df
-2.42414
difference (Peach Street - Plum Street)
1.00431
standard error of difference
0
hypothesized difference
-2.41
t
.0255
p-value (two-tailed)
-5.28173
confidence interval 99.% lower
0.43345
confidence interval 99.% upper
2.85759
margin o ...
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Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year 2.
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year 2.
BUS 640 Introduction Education--bus640.comkopiko222
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million
BUS 640 Inspiring Innovation -- bus640.comkopiko103
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12
1.Suppose your company runs a shuttle business of a hotel to and.docxchristiandean12115
1.Suppose your company runs a shuttle business of a hotel to and from the local airport. The costs for different customer loads are:
1 customer: $30
2 customers: $32
3 customers: $35
4 customers: $38
5 customers: $42
6 customers: $48
7 customers: $57
8 customers: $68.
What are your marginal costs for each customer load level?
Q
TC
MC
Total Rev
Profit
1
30
10
-20
2
32
20
-12
3
35
30
-5
4
38
40
2
5
42
50
8
6
48
60
12
7
57
70
13
8
68
80
12
B. Suppose your company runs a shuttle business of a hotel to and from the local airport. The costs for different customer loads are:
1 customer: $30
2 customers: $32
3 customers: $35
4 customers: $38
5 customers: $42
6 customers: $48
7 customers: $57
8 customers: $68.
If you are compensated $10 per ride, what customer load would you choose?
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MR ≥ MC or you will serve 7 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC < MR or you will serve 10 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC< MR or you will serve 9 customers.
Marginal Cost is the change in costs due to the additional customer. Since marginal revenue is the price of $10, you will serve customers up to the point where MC = MR or you will serve 7 customers.
C. Suppose the number of firms you compete with has recently increased. You estimated that as a result of the increased competition, the demand elasticity has increased from –2 to –3, i.e., you face more elastic demand. You are currently charging $10 for your product. If demand elasticity is -3, you should charge [x].
D. An amusement park, whose customer set is made up of two markets, adults and children, has developed demand schedules as follows:
The marginal operating cost of each unit of quantity is $5. Because marginal cost is a constant, so is average variable cost. Ignore fixed costs. The owners of the amusement part want to maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
14
18
7
13
16
8
12
14
9
11
12
10
10
10
11
9
8
12
8
6
13
7
4
14
6
2
Calculate the price, quantity, and profit if: The amusement park charges a different price in the adult market
Please express your answers for Price and Profit in whole dollars (i.e.10.00)
Please use whole numbers for Quanitity (i.e. 10, 27, 4)
Price
Quantity
Total
Revenue
Marginal
Revenue
Marginal
Cost
Total
Cost
MR-MC
Profit
6
84
5
30
34
13
91
7
5
35
2
56
12
8
96
5
5
40
0
9
99
3
5
45
-2
54
10
100
1
5
50
-4
50
9
11
99
-1
5
55
-6
12
96
-3
5
60
-8
36
7
91
-5
5
65
-10
26
6
14
84
-7
5
70
-12
5
15
75
-9
5
75
-14
0
E. An amusement park, whose customer set is made up of two markets,.
Running head GOVERNMENT 1GOVERNMENT 7Question 1Supp.docxwlynn1
Running head: GOVERNMENT 1
GOVERNMENT 7
Question 1
Suppose the number of firms you compete with has recently increased. You estimated that as a result of the increased competition, the demand elasticity has increased from
–
2 to
–
3, i.e., you face more elastic demand. You are currently charging $10 for your product. If demand elasticity is -3, you should charge [x].
Question 2
An amusement park, whose customer set is made up of two markets, adults and children, has developed demand schedules as follows:
The marginal operating cost of each unit of quantity is $5. Because marginal cost is a constant, so is average variable cost. Ignore fixed costs. The owners of the amusement part want to maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
14
18
7
13
16
8
12
14
9
11
12
10
10
10
11
9
8
12
8
6
13
7
4
14
6
2
Calculate the price, quantity, and profit if: The amusement park charges a different price in the adult market
Please express your answers for Price and Profit in whole dollars (i.e.10.00)
Please use whole numbers for Quanitity (i.e. 10, 27, 4)
Price
Quantity
Total Revenue
Marginal Revenue
Marginal Cost
Total Cost
MR-MC
Profit
84
5.00
30.00
54.00
91
7.00
5.00
35.00
2.00
96
5.00
5.00
40.00
0.00
99
3.00
5.00
45.00
-2.00
100
1.00
5.00
50.00
-4.00
99
-1.00
5.00
55.00
-6.00
96
-3.00
5.00
60.00
-8.00
91
-5.00
5.00
65.00
-10.00
84
-7.00
5.00
70.00
-12.00
75
-9.00
5.00
75.00
-14.00
Question 3
An amusement park, whose customer set is made up of two markets, adults and children, has developed demand schedules as follows:
The marginal operating cost of each unit of quantity is $5. Because marginal cost is a constant, so is average variable cost. Ignore fixed costs. The owners of the amusement part want to maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
14
18
7
13
16
8
12
14
9
11
12
10
10
10
11
9
8
12
8
6
13
7
4
14
6
2
Calculate the price, quantity, and profit if: The amusement park charges a different price in the child's market
Please express your answers for Price and Profit in whole dollars (i.e.10.00)
Please use whole numbers for Quanitity (i.e. 10, 27, 4)
Price
Quantity
Total Revenue
Marginal Revenue
Marginal Cost
Total Cost
MR-MC
Profit
Blank 1
Blank 2
52
5.00
20.00
Blank 3
Blank 4
Blank 5
72
10.00
5.00
30.00
5.00
Blank 6
Blank 7
Blank 8
88
8.00
5.00
40.00
3.00
Blank 9
Blank 10
Blank 11
100
6.00
5.00
50.00
1.00
Blank 12
Blank 13
Blank 14
108
4.00
5.00
60.00
-1.00
Blank 15
Blank 16
Blank 17
112
2.00
5.00
70.00
-3.00
Blank 18
Blank 19
Blank 20
112
0.00
5.00
80.00
-5.00
Blank 21
Blank 22
Blank 23
108
-2.00
5.00
90.00
-7.00
Blank 24
Blank 25
Blank 26
100
-4.00
5.00
100.00
-9.00
Blank 27
Blank 28
Blank 29
88
-6.00
5.00
110.00
-11.00
Blank 30
Question 4
The marginal operating cost of each unit of.
Many people are relatively healthy and have low annual medical cos.docxinfantsuk
Many people are relatively healthy and have low annual medical costs but for some the costs can be extremely high. health economists often model medical costs using the log normal distribution. assuming medical costs are distributed LN (8,3) what is the probability a person pays less than $3,000 in health care in a single year.
Week 4 Practice Worksheet
PSY/315 Version 6
4
Prepare a written response to the following questions.
Chapters 9 &11
1. Two boats, the Prada (Italy) and the Oracle (USA), are competing for a spot in the upcoming America’s Cup race. They race over a part of the course several times. The sample times in minutes for the Prada were: 12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 14.2, and 11.3. The sample times in minutes for the Oracle were: 14.1, 14.1, 14.2, 17.4, 15.8, 16.7, 16.1, 13.3, 13.4, 13.6, 10.8, and 19.0. For data analysis, the appropriate test is the t-Test: Two-Sample Assuming Unequal Variances.
The next table shows the results of this independent t-test. At the .05 significance level, can we conclude that there is a difference in their mean times? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Prada
Oracle
12.170
14.875
mean
1.056
2.208
std. dev.
10
12
n
16
df
-2.7050
difference (Prada - Oracle)
0.7196
standard error of difference
0
hypothesized difference
-3.76
t
.0017
p-value (two-tailed)
-4.2304
confidence interval 95.% lower
-1.1796
confidence interval 95.% upper
1.5254
margin of error
2. The Willow Run Outlet Mall has two Haggar Outlet Stores, one located on Peach Street and the other on Plum Street. The two stores are laid out differently, but both store managers claim their layout maximizes the amounts customers will purchase on impulse. A sample of ten customers at the Peach Street store revealed they spent the following amounts more than planned: $17.58, $19.73, $12.61, $17.79, $16.22, $15.82, $15.40, $15.86, $11.82, $15.85. A sample of fourteen customers at the Plum Street store revealed they spent the following amounts more than they planned when they entered the store: $18.19, $20.22, $17.38, $17.96, $23.92, $15.87, $16.47, $15.96, $16.79, $16.74, $21.40, $20.57, $19.79, $14.83. For Data Analysis, a t-Test: Two-Sample Assuming Unequal Variances was used.
At the .01 significance level is there a difference in the mean amount purchased on an impulse at the two stores? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Peach Street
Plum Street
15.8680
18.2921
mean
2.3306
2.5527
std. dev.
10
14
n
20
df
-2.42414
difference (Peach Str ...
TitleABC123 Version X1Week 4 Practice Worksheet.docxedwardmarivel
Title
ABC/123 Version X
1
Week 4 Practice Worksheet
PSY/315 Version 6
1
University of Phoenix MaterialWeek 4 Practice Worksheet
Prepare a written response to the following questions.
Chapters 9 &11
1. Two boats, the Prada (Italy) and the Oracle (USA), are competing for a spot in the upcoming America’s Cup race. They race over a part of the course several times. The sample times in minutes for the Prada were: 12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 14.2, and 11.3. The sample times in minutes for the Oracle were: 14.1, 14.1, 14.2, 17.4, 15.8, 16.7, 16.1, 13.3, 13.4, 13.6, 10.8, and 19.0. For data analysis, the appropriate test is the t-Test: Two-Sample Assuming Unequal Variances.
The next table shows the results of this independent t-test. At the .05 significance level, can we conclude that there is a difference in their mean times? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Prada
Oracle
12.170
14.875
mean
1.056
2.208
std. dev.
10
12
n
16
df
-2.7050
difference (Prada - Oracle)
0.7196
standard error of difference
0
hypothesized difference
-3.76
t
.0017
p-value (two-tailed)
-4.2304
confidence interval 95.% lower
-1.1796
confidence interval 95.% upper
1.5254
margin of error
2. The Willow Run Outlet Mall has two Haggar Outlet Stores, one located on Peach Street and the other on Plum Street. The two stores are laid out differently, but both store managers claim their layout maximizes the amounts customers will purchase on impulse. A sample of ten customers at the Peach Street store revealed they spent the following amounts more than planned: $17.58, $19.73, $12.61, $17.79, $16.22, $15.82, $15.40, $15.86, $11.82, $15.85. A sample of fourteen customers at the Plum Street store revealed they spent the following amounts more than they planned when they entered the store: $18.19, $20.22, $17.38, $17.96, $23.92, $15.87, $16.47, $15.96, $16.79, $16.74, $21.40, $20.57, $19.79, $14.83. For Data Analysis, a t-Test: Two-Sample Assuming Unequal Variances was used.
At the .01 significance level is there a difference in the mean amount purchased on an impulse at the two stores? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Peach Street
Plum Street
15.8680
18.2921
mean
2.3306
2.5527
std. dev.
10
14
n
20
df
-2.42414
difference (Peach Street - Plum Street)
1.00431
standard error of difference
0
hypothesized difference
-2.41
t
.0255
p-value (two-tailed)
-5.28173
confidence interval 99.% lower
0.43345
confidence interval 99.% upper
2.85759
margin o ...
For more course tutorials visit
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Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year 2.
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year 2.
BUS 640 Introduction Education--bus640.comkopiko222
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million
BUS 640 Inspiring Innovation -- bus640.comkopiko103
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12
BUS 640 HOMEWORK Achievement Education--bus640homework.comclaric150
FOR MORE CLASSES VISIT
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Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year 2.
Describe your answer for each item below
BUS 640 HOMEWORK Become Exceptional--bus640homework.comagathachristie106
The document provides details for two assignments for a business course. Assignment 1 includes two applied problems analyzing consumer demand and production costs. Assignment 2 includes three applied problems analyzing production cost analysis and estimation. The problems require calculating costs, revenues, elasticities, and other metrics to make optimal business decisions around pricing, production levels, and project selection.
BUS 640 HOMEWORK Introduction Education--bus640homework.comagathachristie261
The document provides details for two assignments for a business course. Assignment 1 includes two applied problems analyzing consumer demand and production costs. Assignment 2 includes three applied problems analyzing production cost analysis and estimation. The problems require calculating costs, revenues, profits and other metrics to analyze business decisions for various scenarios involving pricing, production levels, costs and demand.
BUS 640 HOMEWORK Redefined Education--bus640homework.comagathachristie245
The document provides details for two assignments for a business course. Assignment 1 includes two applied problems analyzing consumer demand and production costs. Assignment 2 includes three applied problems analyzing production cost analysis and estimation. The problems require calculating costs, revenues, elasticities, and other metrics to make optimal business decisions around pricing, production levels, and project selection.
BUS 640 HOMEWORK Lessons in Excellence--bus640homework.comthomashard80
The document provides information about assignments for BUS 640 classes, including applied problems involving decision making around donations, investment projects, demand analysis, production costs, market structures, and pricing. There are also assignments on managerial decision making requiring research on a specific company. The problems require showing calculations, describing answers in complete sentences, and applying concepts like present value, expected net present value, demand and cost functions, profit maximization, and elasticities.
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year 2.
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year
This document provides details for two problems assigned in BUS 640. Problem 1 involves calculating the present value of a donation that can be provided in installments over two years at different interest rates. It also asks how this type of decision applies in business. Problem 2 involves analyzing two investment projects (Project A and B) based on their expected net present value, standard deviation, and coefficient of variation to determine which project a company should choose. It provides cash flow details for Project A and states Project B has an ENPV of $32 million and standard deviation of $10.5 million.
This document provides details for two assignments for BUS 640. Problem 1 involves analyzing the present value of a donation given in installments versus a lump sum, and how the decision would change with different interest rates. Problem 2 involves analyzing two investment projects (Project A and B) based on their expected net present value, standard deviation, and coefficient of variation to determine which project is preferred with and without considering risk factors. The document provides data and questions to analyze for both problems.
This document provides details for two problems assigned in BUS 640. Problem 1 involves calculating the present value of a donation that can be provided in installments over two years at different interest rates. It also asks how this type of decision applies in business. Problem 2 involves analyzing two investment projects (Project A and B) for a company based on expected net present value, standard deviation, and risk preferences to determine which project is preferred. It provides data on cash flows and probabilities for Project A over three years.
Economics 101Homework #5Directions The homework will be colle.docxjack60216
Economics 101
Homework #5
Directions: The homework will be collected in a box before the lecture. Please place your name, TA name and section number on top of the homework (legibly). Make sure you write your name as it appears on your ID so that you can receive the correct grade. Late homework will not be accepted so make plans ahead of time. Please show your work. Good luck!
Please realize that you are essentially creating “your brand” when you submit this homework. Do you want your homework to convey that you are competent, careful, professional? Or, do you want to convey the image that you are careless, sloppy, and less than professional. For the rest of your life you will be creating your brand: please think about what you are saying about yourself when you do any work for someone else!
1. Consider a monopolist where the market demand curve for the produce is given by P = 520 – 2Q. This monopolist has marginal costs that can be expressed as MC = 100 + 2Q and total costs that can be expressed as TC = 100Q + Q2 + 50.
a. Given the above information, what is this monopolist’s profit maximizing price and output if it charges a single price?
b. Given the above information, calculate this single price monopolist’s profit.
c. At the profit maximizing quantity, what is this monopolist’s average total cost of production (ATC)?
d. At the profit maximizing quantity, what is the profit per unit for this single price monopolist?
2. Consider a monopolist described by the following equations:
Market demand for monopolist’s product: P = 100 – Q
ATC for monopolist: ATC = 20 +(3/10) Q
MC for monopolist: MC = 20 + (3/5)Q
In this question we will use the above data to compare a single price monopolist to the same monopolist that is regulated either with average cost regulation or marginal cost regulation. At the end of the question you will fill out a table to compare your results.
a. Given the above information, what is the profit maximizing price and quantity for the single price monopolist? You should round your answers to the nearest whole number.
b. Given the above information, what is the level of profit for this single price monopolist?
c. Suppose this monopolist is regulated to produce at that quantity where price equals average total cost. Calculate the quantity the monopolist will produce and the price it will charge given this regulatory scenario.
d. Calculate the level of profits for the monopoly if it is regulated to produce that quantity where price equals average total cost. Explain how you got your answer.
e. Suppose this monopolist is regulated to produce at that quantity where price equals marginal cost. Calculate the quantity the monopolist will produce and the price it will charge given this regulatory scenario.
f. Calculate the level of profits for the monopoly if it is regulated to produce that quantity where price equals marginal cost.
g. How big a subsidy will the monopoly require in order to be willing to produce at t ...
Instructions This is an open-book exam. You may refer to you.docxdirkrplav
Instructions:
This is an open-book exam. You may refer to your text and other course materials as you work on the exam, and you may use a calculator.
Record your answers and work in this document.
There are 25 problems.
Problems #1-12 are multiple choice. Record your choice for each problem.
Problems #13-15 are short answer. Record your answer for each problem.
Problems #16-25 are short answer with work required when directed. When requested, show all work and write all answers in the spaces allotted on the following pages. You may type your work using plain-text formatting or an equation editor, or you may hand-write your work and scan it. In either case, show work neatly and correctly, following standard mathematical conventions. Each step should follow clearly and completely from the previous step. If necessary, you may attach extra pages.
MULTIPLE CHOICE. Record your answer choices.
1.7.
2.8.
3.9.
4.10.
5.11.
6.12.
SHORT ANSWER. Record your answers below.
13. (a)
(b)
(c)
(d)
14. (a)
(b)
(c)
15. (a)
(b)
(c)
SHORT ANSWER with Work Shown. Record your answers and work.
Problem Number
Solution
16
Answers:
(a)
(b)
(c)
Work for (a), (b), and (c):
17
Answer:
Work:
18
Answer:
Work:
19
Answers:
(a)
(b)
(c)
Work for (a) and (b):
20
Answer:
Work:
21
Answer:
Work:
22
Answer:
Work:
23
Answers:
(a)
(b)
(c)
(d)
Work for (b), (c), and (d):
24
Answer:
Work:
25
Answers:
(a)
(b) Region I:
Region II:
Region III:
Region IV:
Work:
MATH 106 Finite Mathematics 2148-OL4-7983-3D
Page 1 of 10
MATH 106 FINAL EXAMINATION
This is an open-book exam. You may refer to your text and other course materials as you work
on the exam, and you may use a calculator. You must complete the exam individually.
Neither collaboration nor consultation with others is allowed. Use of instructors’ solutions
manuals or online problem solving services in NOT allowed.
Record your answers and work on the separate answer sheet provided.
There are 25 problems.
Problems #1–12 are Multiple Choice.
Problems #13–15 are Short Answer. (Work not required to be shown)
Problems #16–25 are Short Answer with work required to be shown.
MULTIPLE CHOICE
1. – 2. Amalgamated Furniture Company makes dining room tables and chairs. A table requires
8 labor-hours for assembling and 2 labor-hours for finishing. A chair requires 2 labor-hours for
assembly and 1 labor-hour for finishing. The maximum labor-hours available per day for
assembling and finishing are 400 and 120, respectively. Production costs are $600 per table and
$150 per chair. Let x represent number of tables and y represent number of chairs made per day.
1. Identify the daily production constraint for finishing:
.
Disaster PlansThe SNS is a pivotal tool in the event of a disa.docxduketjoy27252
Disaster Plans
The SNS is a pivotal tool in the event of a disaster.
Using the Scholarly Library or the Internet, research SNS. Based on your understanding, respond to the following:
· List and explain the types of items a community hospital will require and seek from the SNS in the event of a disaster.
· List and explain at least two concerns you may have when forced to rely on this facility.
· During the creation of disaster plans, it is common and essential that neighboring hospitals work together. List and explain some of the problems that may arise from a disaster plan which may be ten years old and involved all of the local community hospitals at the time it was originally designed.
NOTES FROM CLASS
Disaster planning is planning for the mitigation of the most likely, or most destructive, events based on some rational thought process. Note that this approach recognizes and accepts that it is impossible to plan for every contingency.
The simplest technique for prioritizing between possibility and probability based on threats and vulnerability is to use a matrix comparing the probability of a particular threat occurring. This is then weighed against a similar matrix comparing the potential threat with the observed vulnerabilities.
Differently put, what is the possibility of something happening and if it does, what impact will it have?
Since the attacks of 9/11, the anthrax attack in Washington, DC, and the sniper shootings in 2002, disaster planning in the United States has changed. In the past, hospitals planned for disasters involving mass casualty such as, a plane crash or hazardous material spill. Now hospitals must contend with the idea that they could be the primary targets. They must also realize that in the event of a biohazard attack, they may be the point at which the outbreak is first recognized. They may be the first contaminants.
You must also position your plan from the perspective of both an external bioterrorism attack as well as an internal bioterrorism attack. Your approach, response priorities, and staff involved may be very different between the two types of attack.
Hospitals have traditionally been designed and operated to be open, welcoming places. This would no longer be desirable. Facility hardening and personnel security are now bywords for disaster planning. Hospitals must decide who is to be allowed inside the facility, and who is to be kept out. At the same time, hospitals must be sensitive to confidential medical information being mishandled under the terms of Health Insurance Portability and Accountability Act (HIPAA) and understand that a cyber-attack could be just as dangerous as a bioterrorist attack.
The emergency department may be the first place where victims of a bioterrorist attack are received and the attack is first identified. Hospital staff, especially emergency room staff, is likely to have been exposed and may then have to be quarantined and taken out of commission.
The hospital is.
You can use a calculator to do numerical calculations. No graphing.docxjeffevans62972
This document presents three ethical scenarios involving the use of information technology and personal information:
1) A business owner tracking employee locations using GPS in company vehicles.
2) A security professional being asked to access a background check system by a friend to check on a neighbor.
3) A restaurant owner tracking detailed customer data and purchase histories through a new customer relationship system.
The document poses ethical questions around privacy and appropriate use and protection of personal information in each scenario. It prompts consideration of responsibilities in handling such information and any related actions that should or should not be taken.
QNT Weekly learning assessments - Questions and Answers | UOP E AssignmentsUOP E Assignments
What the benefits of learning QNT 561 Weekly Learning Assessments ? Know from UOP E Assignments which is the largest going online educational portal whose motive is to provide best knowledge to UOP students for final exam. You get QNT 561 weekly learning assessments question and answers, QNT 561 weekly learning assessments 30 questions, QNT 561 weekly learning assessments quiz 1 answers etc in USA.
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This document discusses various pricing strategies that firms can use to maximize profits when facing market power or competition. It begins by explaining standard single pricing and how profits are calculated. It then explores alternatives like price discrimination, two-part pricing, block pricing, bundling, peak-load pricing, cross-subsidies, and strategies for intense price competition. The conclusion compares the strategies and which allow extraction of more consumer surplus based on the information available to the firm.
TitleABC123 Version X1Name____________________________.docxherthalearmont
Title
ABC/123 Version X
1
Name:___________________________________________
Week 4 Practice Worksheet
University of Phoenix MaterialWeek 4 Practice Worksheet
Prepare a written response to the following questions. Complete the questions below. Be specific and provide examples when relevant.
Cite any sources consistent with APA guidelines. Remember our Privitera textbook is required.
Chapters 9 & 11
1. Two boats, the Prada (Italy) and the Oracle (USA), are competing for a spot in the upcoming America’s Cup race. They race over a part of the course several times. The sample times in minutes for the Prada were: 12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 14.2, and 11.3. The sample times in minutes for the Oracle were: 14.1, 14.1, 14.2, 17.4, 15.8, 16.7, 16.1, 13.3, 13.4, 13.6, 10.8, and 19.0. For data analysis, the appropriate test is the t-Test: Two-Sample Assuming Unequal Variances.
The next table shows the results of this independent t-test. At the .05 significance level, can we conclude that there is a difference in their mean times? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Prada
Oracle
12.170
14.875
mean
1.056
2.208
std. dev.
10
12
n
16
df
-2.7050
difference (Prada - Oracle)
0.7196
standard error of difference
0
hypothesized difference
-3.76
t
.0017
p-value (two-tailed)
-4.2304
confidence interval 95.% lower
-1.1796
confidence interval 95.% upper
1.5254
margin of error
2. The Willow Run Outlet Mall has two Haggar Outlet Stores, one located on Peach Street and the other on Plum Street. The two stores are laid out differently, but both store managers claim their layout maximizes the amounts customers will purchase on impulse. A sample of ten customers at the Peach Street store revealed they spent the following amounts more than planned: $17.58, $19.73, $12.61, $17.79, $16.22, $15.82, $15.40, $15.86, $11.82, $15.85. A sample of fourteen customers at the Plum Street store revealed they spent the following amounts more than they planned when they entered the store: $18.19, $20.22, $17.38, $17.96, $23.92, $15.87, $16.47, $15.96, $16.79, $16.74, $21.40, $20.57, $19.79, $14.83. For Data Analysis, a t-Test: Two-Sample Assuming Unequal Variances was used.
At the .01 significance level is there a difference in the mean amount purchased on an impulse at the two stores? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Peach Street
Plum Street
15.8680
18.2921
mean
2.3306
2.5527
std. dev.
10
14
n
20
df
-2.42414
difference (Peach Street - Plum Street)
1.00431
standard error of differe ...
The document discusses issues facing the quality assurance manager of a pharmaceutical company regarding setting the proper fill target amount for bottles of a medication. It considers using a standard deviation rule but notes this could lead to underfilled bottles and production stoppages. Other factors to incorporate are the production process, costs of underfilled bottles, and maximizing profit. Analysis of costs per ounce produced and rejected is needed to determine the optimal target fill amount. The document recommends a target of 10.38 to 10.40 ounces per bottle would maximize profit per case while minimizing rejected bottles given production constraints.
BUSI 620 MENTOR Education Your Life--busi620mentorthomashard44
This document provides materials for the BUSI 620 course, including discussion questions, problems, and papers for each week. It addresses topics such as critical thinking, managerial economics, e-commerce, savings, demand and elasticity. The materials are intended to help students learn concepts through analysis of real-world business scenarios and quantitative problems. Solutions are provided for questions to facilitate self-study for the course.
Most patients with mental health disorders are not aggressive. H.docxhelzerpatrina
Most patients with mental health disorders are not aggressive. However, it is important for nurses to be able to know the signs and symptoms associated with the five phases of aggression, and to appropriately apply nursing interventions to assist in treating aggressive patients. Please read the case study below and answer the four questions related to it.
Aggression Case Study
Christopher, who is 14 years of age, was recently admitted to the hospital for schizophrenia. He has a history of aggressive behavior and states that the devil is telling him to kill all adults because they want to hurt him. Christopher has a history of recidivism and noncompliance with his medications. One day on the unit, the nurse observes Christopher displaying hypervigilant behaviors, pacing back and forth down the hallway, and speaking to himself under his breath. As the nurse runs over to Christopher to talk, he sees that his bedroom door is open and runs into his room and shuts the door. The nurse responds by attempting to open the door, but Christopher keeps pulling the door shut and tells the nurse that if the nurse comes in the room he will choke the nurse. The nurse responds by calling other staff to assist with the situation.
1. What phase of the aggression cycle is Christopher in at the beginning of this scenario? What phase is he in at the end the scenario? (State the evidence that supports your answers).
2. What interventions could have been implemented to prevent Christopher from escalating at the beginning of the scenario?
3. What interventions should the nurse take to deescalate the situation when Christopher is refusing to open his door?
4. If a restrictive intervention (restraint/seclusion) is used, what are some important steps for the nurse to remember?
.
MotivationExplain your motivation for applying to this prog.docxhelzerpatrina
Motivation:
Explain your motivation for applying to this program. How does the content of this study abroad program relate to your future academic and professional goals?
Goals(REQUIRED)
List and explain three concrete goals related to living and studying abroad that you will set for yourself to get the most out of this opportunity.
.
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A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year 2.
Describe your answer for each item below
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BUS 640 HOMEWORK Redefined Education--bus640homework.comagathachristie245
The document provides details for two assignments for a business course. Assignment 1 includes two applied problems analyzing consumer demand and production costs. Assignment 2 includes three applied problems analyzing production cost analysis and estimation. The problems require calculating costs, revenues, elasticities, and other metrics to make optimal business decisions around pricing, production levels, and project selection.
BUS 640 HOMEWORK Lessons in Excellence--bus640homework.comthomashard80
The document provides information about assignments for BUS 640 classes, including applied problems involving decision making around donations, investment projects, demand analysis, production costs, market structures, and pricing. There are also assignments on managerial decision making requiring research on a specific company. The problems require showing calculations, describing answers in complete sentences, and applying concepts like present value, expected net present value, demand and cost functions, profit maximization, and elasticities.
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year 2.
For more course tutorials visit
www.bus640.com
Week 1
Problem 1:
A generous university benefactor has agreed to donate a large amount of money for student scholarships. The money can be provided in one lump sum of $12 million in Year 0 (the current year), or in parts, in which $7 million can be provided at the end of Year 1, and another $7 million can be provided at the end of Year
This document provides details for two problems assigned in BUS 640. Problem 1 involves calculating the present value of a donation that can be provided in installments over two years at different interest rates. It also asks how this type of decision applies in business. Problem 2 involves analyzing two investment projects (Project A and B) based on their expected net present value, standard deviation, and coefficient of variation to determine which project a company should choose. It provides cash flow details for Project A and states Project B has an ENPV of $32 million and standard deviation of $10.5 million.
This document provides details for two assignments for BUS 640. Problem 1 involves analyzing the present value of a donation given in installments versus a lump sum, and how the decision would change with different interest rates. Problem 2 involves analyzing two investment projects (Project A and B) based on their expected net present value, standard deviation, and coefficient of variation to determine which project is preferred with and without considering risk factors. The document provides data and questions to analyze for both problems.
This document provides details for two problems assigned in BUS 640. Problem 1 involves calculating the present value of a donation that can be provided in installments over two years at different interest rates. It also asks how this type of decision applies in business. Problem 2 involves analyzing two investment projects (Project A and B) for a company based on expected net present value, standard deviation, and risk preferences to determine which project is preferred. It provides data on cash flows and probabilities for Project A over three years.
Economics 101Homework #5Directions The homework will be colle.docxjack60216
Economics 101
Homework #5
Directions: The homework will be collected in a box before the lecture. Please place your name, TA name and section number on top of the homework (legibly). Make sure you write your name as it appears on your ID so that you can receive the correct grade. Late homework will not be accepted so make plans ahead of time. Please show your work. Good luck!
Please realize that you are essentially creating “your brand” when you submit this homework. Do you want your homework to convey that you are competent, careful, professional? Or, do you want to convey the image that you are careless, sloppy, and less than professional. For the rest of your life you will be creating your brand: please think about what you are saying about yourself when you do any work for someone else!
1. Consider a monopolist where the market demand curve for the produce is given by P = 520 – 2Q. This monopolist has marginal costs that can be expressed as MC = 100 + 2Q and total costs that can be expressed as TC = 100Q + Q2 + 50.
a. Given the above information, what is this monopolist’s profit maximizing price and output if it charges a single price?
b. Given the above information, calculate this single price monopolist’s profit.
c. At the profit maximizing quantity, what is this monopolist’s average total cost of production (ATC)?
d. At the profit maximizing quantity, what is the profit per unit for this single price monopolist?
2. Consider a monopolist described by the following equations:
Market demand for monopolist’s product: P = 100 – Q
ATC for monopolist: ATC = 20 +(3/10) Q
MC for monopolist: MC = 20 + (3/5)Q
In this question we will use the above data to compare a single price monopolist to the same monopolist that is regulated either with average cost regulation or marginal cost regulation. At the end of the question you will fill out a table to compare your results.
a. Given the above information, what is the profit maximizing price and quantity for the single price monopolist? You should round your answers to the nearest whole number.
b. Given the above information, what is the level of profit for this single price monopolist?
c. Suppose this monopolist is regulated to produce at that quantity where price equals average total cost. Calculate the quantity the monopolist will produce and the price it will charge given this regulatory scenario.
d. Calculate the level of profits for the monopoly if it is regulated to produce that quantity where price equals average total cost. Explain how you got your answer.
e. Suppose this monopolist is regulated to produce at that quantity where price equals marginal cost. Calculate the quantity the monopolist will produce and the price it will charge given this regulatory scenario.
f. Calculate the level of profits for the monopoly if it is regulated to produce that quantity where price equals marginal cost.
g. How big a subsidy will the monopoly require in order to be willing to produce at t ...
Instructions This is an open-book exam. You may refer to you.docxdirkrplav
Instructions:
This is an open-book exam. You may refer to your text and other course materials as you work on the exam, and you may use a calculator.
Record your answers and work in this document.
There are 25 problems.
Problems #1-12 are multiple choice. Record your choice for each problem.
Problems #13-15 are short answer. Record your answer for each problem.
Problems #16-25 are short answer with work required when directed. When requested, show all work and write all answers in the spaces allotted on the following pages. You may type your work using plain-text formatting or an equation editor, or you may hand-write your work and scan it. In either case, show work neatly and correctly, following standard mathematical conventions. Each step should follow clearly and completely from the previous step. If necessary, you may attach extra pages.
MULTIPLE CHOICE. Record your answer choices.
1.7.
2.8.
3.9.
4.10.
5.11.
6.12.
SHORT ANSWER. Record your answers below.
13. (a)
(b)
(c)
(d)
14. (a)
(b)
(c)
15. (a)
(b)
(c)
SHORT ANSWER with Work Shown. Record your answers and work.
Problem Number
Solution
16
Answers:
(a)
(b)
(c)
Work for (a), (b), and (c):
17
Answer:
Work:
18
Answer:
Work:
19
Answers:
(a)
(b)
(c)
Work for (a) and (b):
20
Answer:
Work:
21
Answer:
Work:
22
Answer:
Work:
23
Answers:
(a)
(b)
(c)
(d)
Work for (b), (c), and (d):
24
Answer:
Work:
25
Answers:
(a)
(b) Region I:
Region II:
Region III:
Region IV:
Work:
MATH 106 Finite Mathematics 2148-OL4-7983-3D
Page 1 of 10
MATH 106 FINAL EXAMINATION
This is an open-book exam. You may refer to your text and other course materials as you work
on the exam, and you may use a calculator. You must complete the exam individually.
Neither collaboration nor consultation with others is allowed. Use of instructors’ solutions
manuals or online problem solving services in NOT allowed.
Record your answers and work on the separate answer sheet provided.
There are 25 problems.
Problems #1–12 are Multiple Choice.
Problems #13–15 are Short Answer. (Work not required to be shown)
Problems #16–25 are Short Answer with work required to be shown.
MULTIPLE CHOICE
1. – 2. Amalgamated Furniture Company makes dining room tables and chairs. A table requires
8 labor-hours for assembling and 2 labor-hours for finishing. A chair requires 2 labor-hours for
assembly and 1 labor-hour for finishing. The maximum labor-hours available per day for
assembling and finishing are 400 and 120, respectively. Production costs are $600 per table and
$150 per chair. Let x represent number of tables and y represent number of chairs made per day.
1. Identify the daily production constraint for finishing:
.
Disaster PlansThe SNS is a pivotal tool in the event of a disa.docxduketjoy27252
Disaster Plans
The SNS is a pivotal tool in the event of a disaster.
Using the Scholarly Library or the Internet, research SNS. Based on your understanding, respond to the following:
· List and explain the types of items a community hospital will require and seek from the SNS in the event of a disaster.
· List and explain at least two concerns you may have when forced to rely on this facility.
· During the creation of disaster plans, it is common and essential that neighboring hospitals work together. List and explain some of the problems that may arise from a disaster plan which may be ten years old and involved all of the local community hospitals at the time it was originally designed.
NOTES FROM CLASS
Disaster planning is planning for the mitigation of the most likely, or most destructive, events based on some rational thought process. Note that this approach recognizes and accepts that it is impossible to plan for every contingency.
The simplest technique for prioritizing between possibility and probability based on threats and vulnerability is to use a matrix comparing the probability of a particular threat occurring. This is then weighed against a similar matrix comparing the potential threat with the observed vulnerabilities.
Differently put, what is the possibility of something happening and if it does, what impact will it have?
Since the attacks of 9/11, the anthrax attack in Washington, DC, and the sniper shootings in 2002, disaster planning in the United States has changed. In the past, hospitals planned for disasters involving mass casualty such as, a plane crash or hazardous material spill. Now hospitals must contend with the idea that they could be the primary targets. They must also realize that in the event of a biohazard attack, they may be the point at which the outbreak is first recognized. They may be the first contaminants.
You must also position your plan from the perspective of both an external bioterrorism attack as well as an internal bioterrorism attack. Your approach, response priorities, and staff involved may be very different between the two types of attack.
Hospitals have traditionally been designed and operated to be open, welcoming places. This would no longer be desirable. Facility hardening and personnel security are now bywords for disaster planning. Hospitals must decide who is to be allowed inside the facility, and who is to be kept out. At the same time, hospitals must be sensitive to confidential medical information being mishandled under the terms of Health Insurance Portability and Accountability Act (HIPAA) and understand that a cyber-attack could be just as dangerous as a bioterrorist attack.
The emergency department may be the first place where victims of a bioterrorist attack are received and the attack is first identified. Hospital staff, especially emergency room staff, is likely to have been exposed and may then have to be quarantined and taken out of commission.
The hospital is.
You can use a calculator to do numerical calculations. No graphing.docxjeffevans62972
This document presents three ethical scenarios involving the use of information technology and personal information:
1) A business owner tracking employee locations using GPS in company vehicles.
2) A security professional being asked to access a background check system by a friend to check on a neighbor.
3) A restaurant owner tracking detailed customer data and purchase histories through a new customer relationship system.
The document poses ethical questions around privacy and appropriate use and protection of personal information in each scenario. It prompts consideration of responsibilities in handling such information and any related actions that should or should not be taken.
QNT Weekly learning assessments - Questions and Answers | UOP E AssignmentsUOP E Assignments
What the benefits of learning QNT 561 Weekly Learning Assessments ? Know from UOP E Assignments which is the largest going online educational portal whose motive is to provide best knowledge to UOP students for final exam. You get QNT 561 weekly learning assessments question and answers, QNT 561 weekly learning assessments 30 questions, QNT 561 weekly learning assessments quiz 1 answers etc in USA.
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This document discusses various pricing strategies that firms can use to maximize profits when facing market power or competition. It begins by explaining standard single pricing and how profits are calculated. It then explores alternatives like price discrimination, two-part pricing, block pricing, bundling, peak-load pricing, cross-subsidies, and strategies for intense price competition. The conclusion compares the strategies and which allow extraction of more consumer surplus based on the information available to the firm.
TitleABC123 Version X1Name____________________________.docxherthalearmont
Title
ABC/123 Version X
1
Name:___________________________________________
Week 4 Practice Worksheet
University of Phoenix MaterialWeek 4 Practice Worksheet
Prepare a written response to the following questions. Complete the questions below. Be specific and provide examples when relevant.
Cite any sources consistent with APA guidelines. Remember our Privitera textbook is required.
Chapters 9 & 11
1. Two boats, the Prada (Italy) and the Oracle (USA), are competing for a spot in the upcoming America’s Cup race. They race over a part of the course several times. The sample times in minutes for the Prada were: 12.9, 12.5, 11.0, 13.3, 11.2, 11.4, 11.6, 12.3, 14.2, and 11.3. The sample times in minutes for the Oracle were: 14.1, 14.1, 14.2, 17.4, 15.8, 16.7, 16.1, 13.3, 13.4, 13.6, 10.8, and 19.0. For data analysis, the appropriate test is the t-Test: Two-Sample Assuming Unequal Variances.
The next table shows the results of this independent t-test. At the .05 significance level, can we conclude that there is a difference in their mean times? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Prada
Oracle
12.170
14.875
mean
1.056
2.208
std. dev.
10
12
n
16
df
-2.7050
difference (Prada - Oracle)
0.7196
standard error of difference
0
hypothesized difference
-3.76
t
.0017
p-value (two-tailed)
-4.2304
confidence interval 95.% lower
-1.1796
confidence interval 95.% upper
1.5254
margin of error
2. The Willow Run Outlet Mall has two Haggar Outlet Stores, one located on Peach Street and the other on Plum Street. The two stores are laid out differently, but both store managers claim their layout maximizes the amounts customers will purchase on impulse. A sample of ten customers at the Peach Street store revealed they spent the following amounts more than planned: $17.58, $19.73, $12.61, $17.79, $16.22, $15.82, $15.40, $15.86, $11.82, $15.85. A sample of fourteen customers at the Plum Street store revealed they spent the following amounts more than they planned when they entered the store: $18.19, $20.22, $17.38, $17.96, $23.92, $15.87, $16.47, $15.96, $16.79, $16.74, $21.40, $20.57, $19.79, $14.83. For Data Analysis, a t-Test: Two-Sample Assuming Unequal Variances was used.
At the .01 significance level is there a difference in the mean amount purchased on an impulse at the two stores? Explain these results to a person who knows about the t test for a single sample but is unfamiliar with the t test for independent means.
Hypothesis Test: Independent Groups (t-test, unequal variance)
Peach Street
Plum Street
15.8680
18.2921
mean
2.3306
2.5527
std. dev.
10
14
n
20
df
-2.42414
difference (Peach Street - Plum Street)
1.00431
standard error of differe ...
The document discusses issues facing the quality assurance manager of a pharmaceutical company regarding setting the proper fill target amount for bottles of a medication. It considers using a standard deviation rule but notes this could lead to underfilled bottles and production stoppages. Other factors to incorporate are the production process, costs of underfilled bottles, and maximizing profit. Analysis of costs per ounce produced and rejected is needed to determine the optimal target fill amount. The document recommends a target of 10.38 to 10.40 ounces per bottle would maximize profit per case while minimizing rejected bottles given production constraints.
BUSI 620 MENTOR Education Your Life--busi620mentorthomashard44
This document provides materials for the BUSI 620 course, including discussion questions, problems, and papers for each week. It addresses topics such as critical thinking, managerial economics, e-commerce, savings, demand and elasticity. The materials are intended to help students learn concepts through analysis of real-world business scenarios and quantitative problems. Solutions are provided for questions to facilitate self-study for the course.
Similar to Week 5, Problem Set QuestionsQuestion 1Suppose your company.docx (20)
Most patients with mental health disorders are not aggressive. H.docxhelzerpatrina
Most patients with mental health disorders are not aggressive. However, it is important for nurses to be able to know the signs and symptoms associated with the five phases of aggression, and to appropriately apply nursing interventions to assist in treating aggressive patients. Please read the case study below and answer the four questions related to it.
Aggression Case Study
Christopher, who is 14 years of age, was recently admitted to the hospital for schizophrenia. He has a history of aggressive behavior and states that the devil is telling him to kill all adults because they want to hurt him. Christopher has a history of recidivism and noncompliance with his medications. One day on the unit, the nurse observes Christopher displaying hypervigilant behaviors, pacing back and forth down the hallway, and speaking to himself under his breath. As the nurse runs over to Christopher to talk, he sees that his bedroom door is open and runs into his room and shuts the door. The nurse responds by attempting to open the door, but Christopher keeps pulling the door shut and tells the nurse that if the nurse comes in the room he will choke the nurse. The nurse responds by calling other staff to assist with the situation.
1. What phase of the aggression cycle is Christopher in at the beginning of this scenario? What phase is he in at the end the scenario? (State the evidence that supports your answers).
2. What interventions could have been implemented to prevent Christopher from escalating at the beginning of the scenario?
3. What interventions should the nurse take to deescalate the situation when Christopher is refusing to open his door?
4. If a restrictive intervention (restraint/seclusion) is used, what are some important steps for the nurse to remember?
.
MotivationExplain your motivation for applying to this prog.docxhelzerpatrina
Motivation:
Explain your motivation for applying to this program. How does the content of this study abroad program relate to your future academic and professional goals?
Goals(REQUIRED)
List and explain three concrete goals related to living and studying abroad that you will set for yourself to get the most out of this opportunity.
.
Most public policy is made from within government agencies. Select a.docxhelzerpatrina
Most public policy is made from within government agencies. Select an agency to review for this assignment:
1) Go to
https://www.usa.gov
to begin your search.
2) Next, click on the menu tab labelled “Government Agencies and Elected Officials.”
3) Then, click on “A-Z Index of U.S. Government Agencies.”
4) Select one of the large federal agencies, and review one of its major policies, laws, or regulations.
What is the primary mission of the agency? Select a problem that the agency is attempting to solve. Research the major policy process as it has evolved and identify its major stakeholders. Identify what major factors have contributed to policy ineffectiveness. Is the bureaucracy now too large to provide adequate oversight and future development? Be sure to integrate lessons learned and policy concepts discussed throughout the class. Examples may include security at airports, immigration, education (No Child Left Behind), welfare support, Social Security, health care, etc. Identify government subsidies, tools, and regulations the agency uses to meet its policy goals. Pinpoint supporting agencies, groups, or businesses that would be most interested in these policies, and describe the potential conflicts of interest.
Your APA style paper should be three pages in length, not counting the title and reference pages. Provide at least three peer-reviewed or professional references. Be sure your paper is double-spaced and uses 12-point font and one-inch margins. Use your own words, and include citations and references as needed to avoid plagiarism. All sources used must be referenced; paraphrased and quoted material must have accompanying citations and be cited per APA guidelines.
.
Mr. Smith brings his 4-year-old son to your primary care office. He .docxhelzerpatrina
Mr. Smith brings his 4-year-old son to your primary care office. He states the boy has been ill for three days. Mr. Smith indicates that he would like antibiotics so he can send his son back to pre-school the next day.
History - Child began with sneezing, mild cough, and low grade fever of 100 degrees three days ago. All immunizations UTD. Father reports that the child has had only two incidents of URI and no other illnesses.
Social - non-smoking household. Child attends preschool four mornings a week and is insured through his father’s employment. No other siblings in the household.
PE/ROS -T 99, R 20, P 100. Alert, cooperative, in good spirits, well-hydrated. Mildly erythemic throat, no exudate, tonsils +2. Both ears mild pink tympanic membrane with good movement. Lungs clear bilaterally. All other systems WNL.
Do not consider COVID-19 for this patient diagnosis.
.
Mrs. Walsh, a woman in her 70s, was in critical condition after rep.docxhelzerpatrina
“Mrs. Walsh, a woman in her 70s, was in critical condition after repeat coronary artery bypass graft (CABG) surgery. Her family lived nearby when Mrs. Walsh had her first CABG surgery. They had moved out of town but returned to our institution, where the first surgery had been performed successfully. Mrs. Walsh remained critically ill and unstable for several weeks before her death. Her family was very anxious because of Mrs. Walsh’s unstable and deteriorating condition, and a family member was always with her 24 hours a day for the first few weeks.
The nurse became involved with this family while Mrs. Walsh was still in surgery, because family members were very anxious that the procedure was taking longer than it had the first time and made repeated calls to the critical care unit to ask about the patient. The nurse met with the family and offered to go into the operating room to talk with the cardiac surgeon to better inform the family of their mother’s status.
One of the helpful things the nurse did to assist this family was to establish a consistent group of nurses to work with Mrs. Walsh, so that family members could establish trust and feel more confident about the care their mother was receiving. This eventually enabled family members to leave the hospital for intervals to get some rest. The nurse related that this was a family whose members were affluent, educated, and well informed, and that they came in prepared with lists of questions. A consistent group of nurses who were familiar with Mrs. Walsh’s particular situation helped both family members and nurses to be more satisfied and less anxious. The family developed a close relationship with the three nurses who consistently cared for Mrs. Walsh and shared with them details about Mrs. Walsh and her life.
The nurse related that there was a tradition in this particular critical care unit not to involve family members in care. She broke that tradition when she responded to the son’s and the daughter’s helpless feelings by teaching them some simple things that they could do for their mother. They learned to give some basic care, such as bathing her. The nurse acknowledged that involving family members in direct patient care with a critically ill patient is complex and requires knowledge and sensitivity. She believes that a developmental process is involved when nurses learn to work with families.
She noted that after a nurse has lots of experience and feels very comfortable with highly technical skills, it becomes okay for family members to be in the room when care is provided. She pointed out that direct observation by anxious family members can be disconcerting to those who are insecure with their skills when family members ask things like, “Why are you doing this? Nurse ‘So and So’ does it differently.” She commented that nurses learn to be flexible and to reset priorities. They should be able to let some things wait that do not need to be done right away to give the family some.
Much has been made of the new Web 2.0 phenomenon, including social n.docxhelzerpatrina
Much has been made of the new Web 2.0 phenomenon, including social networking sites and user-created mash-ups. How does Web 2.0 change security for the Internet? Your submission should be between 500 words with references and following APA reference style. Please do not include a title page
.
MSN 5550 Health Promotion Prevention of Disease Case Study Module 2.docxhelzerpatrina
MSN 5550 Health Promotion: Prevention of Disease Case Study Module 2 Instructions: Read the following case study and answer the reflective questions.
Please provide rationales for your answers. Make sure to provide a citation for your answers. Deadline: CASE STUDY:
An Older Immigrant Couple: Mr. and Mrs. Arahan Mr. and Mrs. Arahan, an older couple in their seventies, have been living with their oldest daughter, her husband of 15 years, and their two children, ages 12 and 14. They all live in a middle-income neighborhood in a suburb of a metropolitan city. Mr. and Mrs. Arahan are both college educated and worked full-time while they were in their native country. In addition, Mr. Arahan, the only offspring of wealthy parents, inherited a substantial amount of money and real estate. Their daughter came to the United States as a registered nurse and met her husband, a drug company representative. The older couple moved to the United States when their daughter became a U.S. citizen and petitioned them as immigrants. Since the couple was facing retirement, they welcomed the opportunity to come to the United States. The Arahans found life in the United States different from that in their home country, but their adjustment was not as difficult because both were healthy and spoke English fluently. Most of their time was spent taking care of their two grandchildren and the house. As the grandchildren grew older, the older couple found that they had more spare time. The daughter and her husband advanced in their careers and spent a great deal more time at their jobs. There were few family dinners during the week. On weekends, the daughter, her husband, and their children socialized with their own friends. The couple began to feel isolated and longed for a more active life. Mr. and Mrs. Arahan began to think that perhaps they should return to the home country, where they still had relatives and friends. However, political and economic issues would have made it difficult for them to live there. Besides, they had become accustomed to the way of life in the United States with all the modern conveniences and abundance of goods that were difficult to obtain in their country. However, they also became concerned that they might not be able to tolerate the winter months and that minor health problems might worsen as they aged. They wondered who would take care of them if they became very frail and where they would live, knowing that their daughter had only saved money for their grandchildren’s college education. They expressed their sentiments to their daughter, who became very concerned about how her parents were feeling. This older couple had been attending church on a regular basis, but had never been active in other church-related activities. The church bulletin announced the establishment of parish nursing with two retired registered nurses as volunteers. The couple attended the first opening of the parish clinic. Here, they met one of the registered nur.
MSEL Strategy Mid-term Instructions Miguel Rivera-SantosFormat.docxhelzerpatrina
MSEL Strategy Mid-term Instructions Miguel Rivera-Santos
Format of the Mid-term
· You will find three recent newspaper articles describing a strategic move or a strategic decision in this document. Choose two out of these three articles and, for each of the two articles you have selected, answer the following two questions:
· Q1: What is (are) the issue(s) for the main company in the article? How do you assess the company’s strategic decision(s)? What additional information and what specific analyses would you conduct to fully understand the issue(s) and the decision(s)?
· Q2: What alternative recommendation would you consider in response to the issue(s)? What additional information/analyses would you need for this alternative recommendation? How could it be implemented?
· For each article, the combined answers to these two questions should be no longer than 2 single-spaced pages, in 12-point Times New Roman, with a 1-inch margin all around.
You can add as many appendices as you feel necessary, but remember that the page limitfor the mid-term (excluding exhibits) is 4 pages, i.e., 2 pages per newspaper article.
· You do not need to seek additional information beyond what is provided in the articles.
GOOD LUCK!
Geely to build satellites for self-driving cars - Financial Times (US), 3/4... https://digital.olivesoftware.com/Olive/ODN/FTUS/PrintArticle.aspx?d...
Automobiles
CHRISTIAN SHEPHERD — BEIJING
Geely is aiming to be the first China carmaker to design and build satellites to support its autonomous driving programme, the latest step by founder Li Shufu in his bid to build an industry leader.
Geely, which owns Swedish brand Volvo Cars, Malaysia’s Proton, and a stake in Mercedes-Benz owner Daimler, will invest Rmb2.27bn ($325m) in a new development centre and factory to manufacture satellites this year, the company said yesterday.
The announcement makes Geely the first known Chinese carmaker with plans to build its own satellites. Mr Li’s move sparked comparisons in China media with Elon Musk, founder of electric carmaker Tesla and private space exploration company SpaceX.
Last month Geely drew comparisons with Volkswagen when Mr Li’s holding group announced plans to merge Geely Automobile and Volvo Cars, moving the company towards becoming the first global Chinese carmaker.
Che Jun, Communist party boss of China’s eastern Zhejiang province, where Geely is based, said that the complex would be built in Taizhou city and that construction had begun.
The centre will design, test and manufacture low-orbit communication satellites, purpose-built to improve geolocation of vehicles and to support their connected functions, Geely said.
Geely has been pouring money into new technologies from self-driving cars to flying taxis, spending Rmb20bn on research and development in the past year.
The investments are part of the group’s spend on global expansion, such as buying a $9bn stake in Daimler.
The announcement comes as the coronavirus outbre.
Much of the focus in network security centers upon measures in preve.docxhelzerpatrina
Network security focuses on preventing intrusions and handling security events, but there is debate around proactive measures an organization should take. Practical proactive measures could include monitoring for suspicious activity and strengthening access controls. Biblical principles suggest taking reasonable precautions against probable threats, though excessive measures may violate ethics of non-aggression or forgiveness.
Mt. Baker Hazards Hazard Rating Score High silic.docxhelzerpatrina
Mt. Baker
Hazards
Hazard Rating Score
High silica content of eruptive products, >60% (andesite/dacite/rhyolite)
Major explosive activity within last 500 years
Major explosive activity within last 5000 years
Pyroclastic flows within last 500 years
Mudflows (lahars) within the last 500 years
Destructive tsunami within last 500 years
Occurrence of frequent volcano-seismic crises (volcanic earthquake swarms)
Occurrence of significant ground deformation within last 50 years
SCORE
Risk
Risk Rating Score
Population at risk >100
Population at risk >1,000
Population at risk >10,000
Population at risk >100,000
Population at risk >1,000,000
Historical fatalities
Evacuation as a result of historical eruption(s)
SCORE
TOTAL SCORE ___________
For each of the above queries to which the answer is yes, score 1. For an answer of no, score 0.
If no information is found, assume the answer is no and score 0.
Mt. Hood
Hazards
Hazard Rating Score
High silica content of eruptive products, >60% (andesite/dacite/rhyolite)
Major explosive activity within last 500 years
Major explosive activity within last 5000 years
Pyroclastic flows within last 500 years
Mudflows (lahars) within the last 500 years
Destructive tsunami within last 500 years
Occurrence of frequent volcano-seismic crises (volcanic earthquake swarms)
Occurrence of significant ground deformation within last 50 years
SCORE
Risk
Risk Rating Score
Population at risk >100
Population at risk >1,000
Population at risk >10,000
Population at risk >100,000
Population at risk >1,000,000
Historical fatalities
Evacuation as a result of historical eruption(s)
SCORE
TOTAL SCORE ___________
For each of the above queries to which the answer is yes, score 1. For an answer of no, score 0.
If no information is found, assume the answer is no and score 0.
Mt. Rainier
Hazards
Hazard Rating Score
High silica content of eruptive products, >60% (andesite/dacite/rhyolite)
Major explosive activity within last 500 years
Major explosive activity within last 5000 years
Pyroclastic flows within last 500 years
Mudflows (lahars) within the last 500 years
Destructive tsunami within last 500 years
Occurrence of frequent volcano-seismic crises (volcanic earthquake swarms)
Occurrence of significant ground deformation within last 50 years
SCORE
Risk
Risk Rating Score
Population at risk >100
Population at risk >1,000
Population at risk >10,000
Population at risk >100,000
Population at risk >1,000,000
Historical fatalities
Evacuation as a result of historical eruption(s)
SCORE
TOTAL SCORE ___________
For each of the above queries to which the answer is yes, score 1. For an answer of no, score 0.
If no information is found, assume the answer is no and score 0.
Mt. St. Helens
Hazards
Hazard Rating Score
High.
Motivation and Cognitive FactorsQuestion AAlfred Hit.docxhelzerpatrina
Motivation and Cognitive Factors
Question A
Alfred Hitchcock reputedly said, “When an actor comes to me and wants to discuss his character, I say, “It’s in the script.” If he says, “But what’s my motivation,” I say, “Your salary.” Discuss motivation based on extrinsic rewards in comparison to that motivated by intrinsic rewards. Are different types of motivations preferable for different tasks? Remember to explain and cite educational sources to support the ideas within the post.
Question B
Social cognitive theory suggests that our beliefs and feelings influence our behavior. What beliefs (cognitive factors) might be related to the specific behavior of going to college? Remember to explain and cite educational sources to support the ideas within the post.
OR
Select one of the personality tests from
Similar Minds
. Take the test, read your results and reproduce them in your journal. What parts of the results ring true to you? What do not? Remember to explain and cite educational sources to support the ideas within the post.
View your discussion
rubric
.
13
.
Motivation in OrganizationsMotivation i.docxhelzerpatrina
Motivation in Organizations
*
Motivation in Organizations
Chapter 7
Chapter 7 Preview:
Motivation in OrganizationsWhat do individuals need to do to meet a personal goal? What are the most important sources of work motivation (e.g., money? recognition? other?)What do you think makes for effective goal-setting? What happens when people feel that they are underpaid compared to their peers? What do people need to believe about a possible reward, in order for it to be motivating?
Components of motivation: What are the basic components of motivation? Page Ref: 214
Motivation: What motivates people to work? What are the most important sources of work motivation? Page Ref: 215
Guidelines for setting effective performance goals: What are they? Page Ref: 220-223
Equity Theory: What are some possible reactions to inequity? Page Ref: 226-227
Expectancy Theory: What are the three types of beliefs that people have, and what do they mean? Page Ref: 230
Copyright
Learning ObjectivesDefine motivation and explain its importance in the field of organizational behavior.Identify and explain the conditions through which goal setting can be used to improve job performance.
Learning ObjectivesDescribe equity theory and how it may be applied to motivating people in organizations.Describe expectancy theory and how it may be applied in organizations.
*
Today’s AgendaMotivationGoal SettingEquity TheoryExpectancy Theory
*
Today’s AgendaMotivationGoal SettingEquity TheoryExpectancy Theory
*
The set of processes thatarousedirect, and maintain
human behavior toward attaining some goal
Motivation
*
Motivation Components
*
Motivation
Key PointsMotivation and job performance are not synonymousMotivation is multifacetedPeople are motivated by more than just money
*
What Motivates You to Work?
*
What Motivates People to Work?
*
Today’s AgendaMotivationGoal SettingEquity TheoryExpectancy Theory
*
Goal Setting
*
Goal Setting
Do you have goals?Have you been successful in meeting them?What do you think are important characteristics of attainable goals?How does it make you feel to achieve goals?
*
Goal Setting Guidelines
For ManagersAssign specific goalsAssign difficult, but acceptable, performance goalsstretch goalsProvide feedback on goal attainment
*
Today’s AgendaMotivationGoal SettingEquity TheoryExpectancy Theory
*
Equity TheoryPeople strive to maintain ratios of their own outcomes (rewards) to their own inputs (contributions) that are equal to the outcome / input ratios of others with whom they compare themselves
*
Equity Theory
Possible Reactions to Inequity
*
Equity Theory
Managerial ImplicationsAvoid underpaymentAvoid overpaymentBe honest and open with employees
*
Equity Theory
Pay Practices in the NewsPay Practices at Reddit, Google and Gravity Payments
*
Equity Theory
Pay Practices in the NewsQuestions to co.
Motivations to Support Charity-Linked Events After Exposure to.docxhelzerpatrina
Motivations to Support Charity-Linked Events After Exposure to
Facebook Appeals: Emotional Cause Identification and Distinct
Self-Determined Regulations
Kaspar Schattke
Université du Québec à Montréal
Ronald Ferguson and Michèle Paulin
Concordia University
Nonprofit organizations are increasingly dependent on the involvement of Millennial
constituencies. Three studies investigated their motivations to support charity-linked
events: emotional identification with a cause, self-determination theory (SDT) regula-
tions, and context-related Facebook promotions. This article addresses the recent call to
expand SDT research from a simple analysis of autonomous versus controlled moti-
vation, to studying the effects of all the regulations in the SDT continuum, in particular,
the inclusion of the tripartite dimensions of intrinsic motivation and integrated moti-
vation. Results demonstrated that the greater the emotional identification with the
cause, the stronger was the tendency to support the charity-linked event. Also, the
results in these social media contexts revealed that specific intrinsic dimensions (e.g.,
experience stimulation) are motivators of online and offline support, as is the personal
value nature of integrated regulation. Whereas only autonomous motivational regula-
tions predicted support for the two events organized specifically a for charitable causes,
both autonomous and controlled regulations predicted support of a for-profit event
organized with a charitable cause as an adjunct. These findings can assist practitioners
in designing more effective social media communications in support of charity-linked
events.
Keywords: social media, self-determination theory, integrated regulation, tripartite
model of intrinsic motivation, charitable causes
Supplemental materials: http://dx.doi.org/10.1037/mot0000085.supp
Social media is a new domain offering excit-
ing opportunities to investigate research ques-
tions in social psychology (Greitemeyer, 2011;
Kende, Ujhelyi, Joinson, & Greitemeyer, 2015).
Our research examined motivation to support
charity-linked events of nonprofit organizations
that are currently faced with increased compe-
tition for resources and declining government
support (Paulin, Ferguson, Jost, & Fallu, 2014;
Reed, Aquino, & Levy, 2007; White & Peloza,
2009). Presently, they depend on an ageing set
of traditional supporters (Urbain, Gonzalez, &
Le Gall-Ely, 2013). However, their future suc-
cess lies in ensuring the sustainable involve-
ment of the Millennial generation (Fine, 2009),
distinguished from other generations by their
intense exposure at an early age to interactive
technology and social media (Bolton et al.,
2013).
Facebook, the most detailed social media, is
used primarily to maintain or solidify existing
offline relationships allowing people to develop
a public or semipublic profile and to emotion-
ally participate with those whom they can share
This article was published Online First December .
Mrs. Walsh, a woman in her 70s, was in critical condition after.docxhelzerpatrina
“Mrs. Walsh, a woman in her 70s, was in critical condition after repeat coronary artery bypass graft (CABG) surgery. Her family lived nearby when Mrs. Walsh had her first CABG surgery. They had moved out of town but returned to our institution, where the first surgery had been performed successfully. Mrs. Walsh remained critically ill and unstable for several weeks before her death. Her family was very anxious because of Mrs. Walsh’s unstable and deteriorating condition, and a family member was always with her 24 hours a day for the first few weeks.
The nurse became involved with this family while Mrs. Walsh was still in surgery, because family members were very anxious that the procedure was taking longer than it had the first time and made repeated calls to the critical care unit to ask about the patient. The nurse met with the family and offered to go into the operating room to talk with the cardiac surgeon to better inform the family of their mother’s status.
· One of the helpful things the nurse did to assist this family was to establish a consistent group of nurses to work with Mrs. Walsh, so that family members could establish trust and feel more confident about the care their mother was receiving. This eventually enabled family members to leave the hospital for intervals to get some rest. The nurse related that this was a family whose members were affluent, educated, and well informed, and that they came in prepared with lists of questions. A consistent group of nurses who were familiar with Mrs. Walsh’s particular situation helped both family members and nurses to be more satisfied and less anxious. The family developed a close relationship with the three nurses who consistently cared for Mrs. Walsh and shared with them details about Mrs. Walsh and her life.
· The nurse related that there was a tradition in this particular critical care unit not to involve family members in care. She broke that tradition when she responded to the son’s and the daughter’s helpless feelings by teaching them some simple things that they could do for their mother. They learned to give some basic care, such as bathing her. The nurse acknowledged that involving family members in direct patient care with a critically ill patient is complex and requires knowledge and sensitivity. She believes that a developmental process is involved when nurses learn to work with families.
· She noted that after a nurse has lots of experience and feels very comfortable with highly technical skills, it becomes okay for family members to be in the room when care is provided. She pointed out that direct observation by anxious family members can be disconcerting to those who are insecure with their skills when family members ask things like, “Why are you doing this? Nurse ‘So and So’ does it differently.” She commented that nurses learn to be flexible and to reset priorities. They should be able to let some things wait that do not need to be done right away to give the famil.
MOVIE TITLE IS LIAR LIAR starring JIM CARREYProvide the name o.docxhelzerpatrina
MOVIE TITLE IS LIAR LIAR starring JIM CARREY
Provide the name of the movie, television series, or streaming series you chose, including a summary of the content, and explain why you selected it.
What are your impressions of the environments (include graphic elements)?
Pay attention to the relationships and communication occurring in the movie. How are people greeting each other? How are people interacting? Do you think you can tell the relationships of the people based on their verbal and nonverbal behaviors? Why or why not?
What are the cultural verbal cues that you notice in the movie?
What are the cultural nonverbal cues that you notice in the movie?
Describe two of the characters' use of language including word arrangement, word choice, and intended meaning.
Summarize how your content choice provided sufficient detail allowing you to describe the roles of verbal and nonverbal elements in communication and how the two forms of communication work in conjunction.
.
mple selection, and assignment to groups (as applicable). Describe.docxhelzerpatrina
The document outlines the process and procedures for a research project. It discusses obtaining informed consent from participants, analyzing demographic and other collected data through descriptive statistics, and addressing each research question or PICOT question through specific inferential statistics. It also covers ensuring the data meets assumptions for the statistics used and setting an alpha level. Finally, it addresses considering and dealing with any ethical issues regarding methodology, design, data collection, anonymity, confidentiality, informed consent, and conflicts of interest in line with the Belmont Report.
More and more businesses have integrated social media into every asp.docxhelzerpatrina
More and more businesses have integrated social media into every aspect of their communication strategies and there are many recent examples of employees being fired from their jobs for personal social media postings. Discuss the benefits and pitfalls of using social media within businesses and if you think it is ethical for business to fire employees for personal use of social media. How can you monitor and control your own social media activities to prevent such a professional conflict?
.
Module Five Directions for the ComparisonContrast EssayWrite a.docxhelzerpatrina
The document provides directions for writing a five paragraph comparison/contrast essay on NASA's past Apollo missions to the Moon and planned future missions to Mars. Students are asked to use MLA style with sources cited and include photos/illustrations to document the similarities and differences between the two missions. NASA.gov is listed as a primary source for quotations and the works cited page, along with other sources from the library databases or Google. A sample outline is provided with an introduction, paragraphs on similarities/differences, and a conclusion.
Monica asked that we meet to see if I could help to reduce the d.docxhelzerpatrina
Monica asked that we meet to see if I could help to reduce the differences between them. When the time came, she started the conversation by saying that Richard wasn’t saving any money at all. They hadn’t started implementing. She said he spent a good deal of time buy- ing and selling stocks. He seemed to be influenced by the weekly ups and downs of the market. At least temporarily, however, he had raised the quality of the stocks he was buying.
Richard seemed a little annoyed and said that Monica never wanted to sell any securities. She almost always told him to wait. She said the shares would come back. When I asked what money meant to them, Richard said an opportunity to gamble and Monica replied a chance to lose what you’ve accumulated. As far as their long-term goals were concerned, Richard said he had no real long-term goals. The future was too fickle. He said who knew what fate had in store for them. Monica’s goal was to feel secure. I had the feeling that her remark was in response to Richard’s behavior. She wouldn’t allow herself to think of anything beyond security until Richard’s activities could be controlled.
Case Application Questions
1. What should be done about Richard’s spending?
2. What kind of investment behavior is Richard demonstrating?What can be done about it? 3. What is Monica’s investment behavior called? How can it be helped?
4. Contrast their two views of money. Do you have any recommendations?
5. How can Monica’s fears be dealt with?
.
Module 6 AssignmentPlease list and describe four types of Cy.docxhelzerpatrina
Module 6 Assignment
Please list and describe four types of Cyber crime.
Rubric for Assignment submission
Criterion
Description
Points possible
Content
Student posts and describes four types of Cyber crimes
40
Word count
500 words
10
Total Points possible
50
.
Elevate Your Nonprofit's Online Presence_ A Guide to Effective SEO Strategies...TechSoup
Whether you're new to SEO or looking to refine your existing strategies, this webinar will provide you with actionable insights and practical tips to elevate your nonprofit's online presence.
How to Manage Reception Report in Odoo 17Celine George
A business may deal with both sales and purchases occasionally. They buy things from vendors and then sell them to their customers. Such dealings can be confusing at times. Because multiple clients may inquire about the same product at the same time, after purchasing those products, customers must be assigned to them. Odoo has a tool called Reception Report that can be used to complete this assignment. By enabling this, a reception report comes automatically after confirming a receipt, from which we can assign products to orders.
🔥🔥🔥🔥🔥🔥🔥🔥🔥
إضغ بين إيديكم من أقوى الملازم التي صممتها
ملزمة تشريح الجهاز الهيكلي (نظري 3)
💀💀💀💀💀💀💀💀💀💀
تتميز هذهِ الملزمة بعِدة مُميزات :
1- مُترجمة ترجمة تُناسب جميع المستويات
2- تحتوي على 78 رسم توضيحي لكل كلمة موجودة بالملزمة (لكل كلمة !!!!)
#فهم_ماكو_درخ
3- دقة الكتابة والصور عالية جداً جداً جداً
4- هُنالك بعض المعلومات تم توضيحها بشكل تفصيلي جداً (تُعتبر لدى الطالب أو الطالبة بإنها معلومات مُبهمة ومع ذلك تم توضيح هذهِ المعلومات المُبهمة بشكل تفصيلي جداً
5- الملزمة تشرح نفسها ب نفسها بس تكلك تعال اقراني
6- تحتوي الملزمة في اول سلايد على خارطة تتضمن جميع تفرُعات معلومات الجهاز الهيكلي المذكورة في هذهِ الملزمة
واخيراً هذهِ الملزمة حلالٌ عليكم وإتمنى منكم إن تدعولي بالخير والصحة والعافية فقط
كل التوفيق زملائي وزميلاتي ، زميلكم محمد الذهبي 💊💊
🔥🔥🔥🔥🔥🔥🔥🔥🔥
A Free 200-Page eBook ~ Brain and Mind Exercise.pptxOH TEIK BIN
(A Free eBook comprising 3 Sets of Presentation of a selection of Puzzles, Brain Teasers and Thinking Problems to exercise both the mind and the Right and Left Brain. To help keep the mind and brain fit and healthy. Good for both the young and old alike.
Answers are given for all the puzzles and problems.)
With Metta,
Bro. Oh Teik Bin 🙏🤓🤔🥰
Andreas Schleicher presents PISA 2022 Volume III - Creative Thinking - 18 Jun...EduSkills OECD
Andreas Schleicher, Director of Education and Skills at the OECD presents at the launch of PISA 2022 Volume III - Creative Minds, Creative Schools on 18 June 2024.
Level 3 NCEA - NZ: A Nation In the Making 1872 - 1900 SML.pptHenry Hollis
The History of NZ 1870-1900.
Making of a Nation.
From the NZ Wars to Liberals,
Richard Seddon, George Grey,
Social Laboratory, New Zealand,
Confiscations, Kotahitanga, Kingitanga, Parliament, Suffrage, Repudiation, Economic Change, Agriculture, Gold Mining, Timber, Flax, Sheep, Dairying,
Creative Restart 2024: Mike Martin - Finding a way around “no”Taste
Ideas that are good for business and good for the world that we live in, are what I’m passionate about.
Some ideas take a year to make, some take 8 years. I want to share two projects that best illustrate this and why it is never good to stop at “no”.
Creative Restart 2024: Mike Martin - Finding a way around “no”
Week 5, Problem Set QuestionsQuestion 1Suppose your company.docx
1. Week 5, Problem Set Questions:
Question 1
Suppose your company runs a shuttle business of a hotel to and
from the local airport. The costs for different customer loads
are:
1 customer: $30
2 customers: $32
3 customers: $35
4 customers: $38
5 customers: $42
6 customers: $48
7 customers: $57
8 customers: $68.
What are your marginal costs for each customer load level?
Q
TC
MC
Total Rev
Profit
1
30
10
-20
2
32
2
20
-12
3
35
3
30
2. -5
4
38
3
40
2
5
42
4
50
8
6
48
6
60
12
7
57
9
70
Question 2
Suppose your company runs a shuttle business of a hotel to and
from the local airport. The costs for different customer loads
are:
1 customer: $30
2 customers: $32
3 customers: $35
4 customers: $38
5 customers: $42
6 customers: $48
7 customers: $57
8 customers: $68.
If you are compensated $10 per ride, what customer load would
you choose?
3. Marginal Cost is the change in costs due to the additional
customer. Since marginal revenue is the price of $10, you will
serve customers up to the point where MR ≥ MC or you will
serve 7 customers.
Marginal Cost is the change in costs due to the additional
customer. Since marginal revenue is the price of $10, you will
serve customers up to the point where MC < MR or you will
serve 10 customers.
Marginal Cost is the change in costs due to the additional
customer. Since marginal revenue is the price of $10, you will
serve customers up to the point where MC< MR or you will
serve 9 customers.
Marginal Cost is the change in costs due to the additional
customer. Since marginal revenue is the price of $10, you will
serve customers up to the point where MC = MR or you will
serve 7 customers.
Question 3
Suppose the number of firms you compete with has recently
increased. You estimated that as a result of the increased
competition, the demand elasticity has increased from –2 to –3,
i.e., you face more elastic demand. You are currently charging
$10 for your product. If demand elasticity is -3, you should
charge [x].
4. Question 4
An amusement park, whose customer set is made up of two
markets, adults and children, has developed demand schedules
as follows:
The marginal operating cost of each unit of quantity is $5.
Because marginal cost is a constant, so is average variable cost.
Ignore fixed costs. The owners of the amusement part want to
maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
14
5. 18
7
13
16
8
12
14
9
11
12
10
10
10
11
9
8
12
8
6
13
7
4
14
6
2
Calculate the price, quantity, and profit if: The amusement park
charges a different price in the adult market
Please express your answers for Price and Profit in whole
dollars (i.e.10.00)
Please use whole numbers for Quanitity (i.e. 10, 27, 4)
Price
Quantity
Total
Revenue
8. 6
14
84
-7
5
70
-12
5
15
75
-9
5
75
-14
0
Question 5
An amusement park, whose customer set is made up of two
markets, adults and children, has developed demand schedules
as follows:
The marginal operating cost of each unit of quantity is $5.
Because marginal cost is a constant, so is average variable
cost. Ignore fixed costs. The owners of the amusement part
want to maximize profits.
Price ($)
Quantity
Adults
Children
5
15
20
6
12. 32
6
18
108
-2
5
90
-7
18
5
20
100
-4
5
100
-9
0
Question 6
An amusement park, whose customer set is made up of two
markets, adults and children, has developed demand schedules
as follows:
The marginal operating cost of each unit of quantity is $5.
Because marginal cost is a constant, so is average variable cost.
Ignore fixed costs. The owners of the amusement part want to
maximize profits.
Price ($)
Quantity
Adults
Children
5
15
17. Question 8
Time Warner could offer the History Channel (H) and Showtime
(S) individually or as a bundle of both.
Suppose the reservation prices of customers 1 and 2 (the highest
prices they are willing to pay) are presented in the boxes below.
The cost to Time Warner is $1 per customer for licensing fees.
Preferences
Showtime
History Chanel
Customer 1
9
2
Customer 2
3
8
Should Time Warner bundle or sell separately? Your answer
needs to include the unbundled and bundled profits.
Question 9
Suppose Time Warner could sell Showtime for $9, and History
channel for $8, while making Showtime-History bundle
available for $13. Should it use mixed bundling. i.e., sells
products both separately and as a bundle?
Your answer must include the profit with mixed bundling.
18. RESEARCH ARTICLE
Molecular Diagnosis of Chagas Disease in
Colombia: Parasitic Loads and Discrete
Typing Units in Patients from Acute and
Chronic Phases
CarolinaHernández1,2,ZulmaCucunubá1,2,CarolinaFlórez1,2,M
arioOlivera1,2,
CarlosValencia1,2,PilarZambrano2,CieloLeón1,2,JuanDavidRa
mírez3*
1 RedChagasColombia,InstitutoNacionalde
Salud,Bogotá,Colombia,2 Grupode Parasitología,
InstitutoNacionalde Salud,Bogotá,Colombia,3 Grupode
InvestigacionesMicrobiológicas-UR(GIMUR),
Programa de Biología,Facultad de CienciasNaturalesy
Matemáticas, Universidad el Rosario,Bogotá,
Colombia
* [email protected]
19. Abstract
Background
The diagnosis of Chagas disease is complex due to the dynamics
of parasitemia in the clini-
cal phases of the disease. The molecular tests have been
consideredpromissorybecause
they detect the parasite in all clinicalphases.Trypanosoma
cruzipresentssignificant
geneticvariabilityand is classified into six DiscreteTyping Units
TcI-TcVI(DTUs)with the
emergenceof foreseen genotypes withinTcI as TcIDomand TcI
Sylvatic. The objective of
this study was to determinethe operatingcharacteristicsof
molecular tests (conventional
and Real Time PCR) for the detectionofT.cruziDNA, parasitic
loads and DTUs in a large
cohortof Colombianpatients fromacute and chronicphases.
Methodology/PrincipalFindings
Sampleswere obtainedfrom708 patients in all clinical phases.
Standarddiagnosis (direct
and serological tests)and molecular tests (conventional PCR and
quantitativePCR) target-
ing the nuclear satelliteDNA region.The genotypingwas
performedby PCR using the
intergenicregionof the mini-exon gene, the 24Sa, 18S and A10
regions.The operating
20. capabilitiesshowed thatperformanceof qPCR was
highercomparedto cPCR. Likewise,
the performance of qPCR was significantlyhigher in acute phase
comparedwith chronic
phase. The median parasitic loads detectedwere 4.69 and 1.33
parasite equivalents/mLfor
acute and chronicphases. The main DTU identifiedwas TcI
(74.2%).TcIDomgenotype
was significantlymorefrequent in chronicphase comparedto
acute phase (82.1%vs
16.6%).The medianparasitic load for TcIDomwas
significantlyhighercomparedwith TcI
Sylvatic in chronic phase (2.58vs.0.75 parasite equivalents/ml).
PLOS NeglectedTropical Diseases |
DOI:10.1371/journal.pntd.0004997 September 20,2016 1 / 20
a11111
OPEN ACCESS
Citation: Hernández C, Cucunubá Z, Flórez C,
Olivera M, Valencia C, Zambrano P, et al. (2016)
Molecular Diagnosis of Chagas Disease in Colombia:
Parasitic Loads and Discrete Typing Units in Patients
from Acute and Chronic Phases. PLoS Negl Trop Dis
10(9): e0004997.doi:10.1371/journal.pntd.0004997
Editor: Alain Debrabant, US Food and Drug
22. standarddiagnosis of Chagas dis-
ease, specifically in acute phase showing high
discriminativepower. However, it is neces-
saryto improve the sensitivityof molecular tests in chronic
phase. The frequencyand
parasitemiaof TcIDomgenotype in chronic patientshighlight its
possible relationshipto the
chronicityof the disease.
Author Summary
Chagas disease is a neglected tropical disease caused by the
parasite Trypanosoma cruzi
that shows tremendous genetic diversity evinced in at least six
Discrete Typing Units and
massive genetic diversity within TcI. Two clinical phases exist
where acute phase shows
high parasitemia and chronic phase shows low and intermittent
parasite dynamics. One
particularity of the disease is the diagnosis, because the
parasitemia is highly variable dur-
ing the phases of the disease. Molecular tests allow detecting
DNA of the parasite in all
clinical phases. Herein, we determined the operating
characteristics of two molecular tests
(cPCR and qPCR) to evaluate the performance of these tests for
diagnosis of Chagas dis-
ease in 708 Colombian patients. We determined the parasitic
loads and DTUs to assess
how is the behaviour of these characteristics in relation to the
clinical phases. We found
that the performance of qPCR was higher compared to cPCR
23. and the molecular tests are a
precise tool for diagnostic of Chagas disease, mainly in the
acute phase. The parasitemia
was higher in the acute phase compared to chronic phase and
the DTU predominant in
Colombian patients was TcI. The behaviour of TcIDom
genotype in the chronic phase
patients evidenced possible relationship with the chronicity of
the disease.
Introduction
Chagas disease is a zoonotic parasitic disease caused by the
protozoan Trypanosoma cruzi. It is
considered a public health problem in Latin-America, where
approximately 6 million people
are currently infected [1]. The acute phase of the disease is
characterised by usually mild fever
that in a small proportion of cases can be accompanied by
myocarditis and other lethal compli-
cations. Most of the patients continue through the chronic phase
that is initially characterised
by an asymptomatic clinical course during two or three decades,
and about 30% of the infected
patients will develop heart or digestive complications
afterwards [2].
T. cruzi parasite shows significant genetic variability and
classified into at least six Discrete
Typing Units TcI-TcVI (DTUs), that present associations with
the geographical distribution,
epidemiological transmission cycles, insect vectors and clinical
manifestations of Chagas dis-
ease [3–5]. Recent studies suggest the occurrence of an
emerging clade within TcI named TcI-
Dom which is distributed in the Americas and associated with
domestic cycles of transmission
24. and human infection [6–10]. Recently, a genotype detected in
anthropogenic bats and named
as TcBat has been described in Panama, Ecuador, Colombia and
Brazil including a case of
human infection in Colombia [11–14].
The diagnosis of Chagas disease is complex due to the dynamics
of parasitemia in the phases
of the disease. During the acute phase the parasitemia is high,
therefore the diagnosis is per-
formed by direct parasitological tests [15,16]. Nevertheless,
direct parasitological tests are not
Diagnosis and Genotyping ofT.cruzi in Acuteand ChronicPhases
PLOS NeglectedTropical Diseases |
DOI:10.1371/journal.pntd.0004997 September 20,2016 2 / 20
Competing Interests: The authors have declared
that no competinginterests exist.
useful in the chronic phase due to the low and intermittent
parasitemias. Therefore, the diag-
nosis of Chagas disease in the chronic phase is determined by
serological tests such as ELISA:
enzyme-linked immunosorbent assay, IFA: indirect
immunofluorescence assay or HAI: Hem-
agglutination Inhibition Test [17–19]. Recently, molecular
techniques such as cPCR (conven-
tional PCR) and qPCR (quantitative real-time PCR) have been
considered as supportive
diagnostic tests due to their ability to determine parasitic loads
of T. cruzi in all clinical phases
of the disease [20–22]. The operating characteristics of
25. molecular tests for diagnosis of T. cruzi
infection have varied according to clinical phase and technical
specifications. Sensitivity for
identifying chronic infection with cPCR has ranged between 22
and 75% [23,24] and in both
cases with a specificity of 100%. Contrastingly, for qPCR,
sensitivity has ranged between 60
and 80% [22,25,26] in chronic phase and between 88% and
100% for acute phase [25,26],
whereas specificity is between 70–100% [26–28]. Sampling
methods have not been always
clearly stated and the role of these techniques for diagnosis of
Chagas disease in the different
clinical phases still remains poorly understood.
The objective of this work was to determine the operating
capabilities of qPCR and cPCR
targeting the satellite nuclear DNA region, compared with
standard diagnosis methods for
acute and chronic Chagas disease. Additionally, we evaluated
the plausible associations
between parasitic load and DTUs in Colombian patients from
the acute and chronic phases to
untangle the natural course of T. cruzi infection in terms of
parasite dynamics.
MaterialsandMethods
Participants
All patients who attended the Colombian National Health
Institute (Overall 985 individuals)
seeking diagnostic tests for Chagas disease in acute (113
patients) or chronic phase (872
patients) between 2004 and 2015 were considered as potential
participants. Inclusion criteria
were: i. Clinical or epidemiological suspect of Chagas disease
26. in acute or chronic phase ii. Not
having received aetiological treatment for Chagas disease iii.
Positive serological tests for Cha-
gas disease (IFA, ELISA and/or HAI) iv. Adequate blood and
serum samples available for per-
forming diagnostic tests according to the clinical phase. v.
Acceptance to participate and sign
the informed consent.
Ethicalstatement
The Technical Research Committee and Ethics Research Board
at the National Health Institute
in Bogotá, Colombia approved the study protocol CTIN-014-11.
Participation was voluntary
and patients were asked for informed written consent
authorising to take blood and serum
samples and access information on their clinical records.
Samplesize calculationand samplingmethods
The total sample size (N) was calculated for test binary
outcomes and separately for each clini-
cal phase: acute and chronic. Considering, n = Z2 S (1−S) d2,
where for a confidence level of
95% (1- α, with α = 0.05) Z is inserted by 1.96, and a maximum
marginal error of estimate, d, is
a desired value for precision based on researchers judgment,
and S is a pre-determined value of
sensitivity [29]. Based in previous studies, for the acute phase S
was pre-established at 92% and
with d at 8% [25,26], whereas for chronic phase S was pre-
established at 60% with d at 5% [22–
26]. Then, N = n /P, being P the estimated prevalence in this
specific population under study.
Given this is a selected population, composed of patients with
some suspicion of the infection
and remitted to a reference centre, P was specified at 60% in
27. suspected cases for both acute and
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chronic phases. This value was obtained as an approximation
based on the laboratory records
at the NHI (Bogota, Colombia). The minimum total sample sizes
were then calculated as
N = 74 and N = 615 for suspected cases in acute and chronic
phases respectively. The tests
were performed to all subjects without knowing their previous
clinical status. Clinical evalua-
tion was conducted simultaneously to all individuals as part of
the study to determine health
status and then to the confirmed cases to evaluate heart
complications. The inclusion of partici-
pants was conducted retrospectively for the period 2004 to
2012, and prospectively between
2013 and 2015. At the end, a total of 86 suspected acute
patients and 622 suspected chronic
patients were included in the study (Table 1).
Clinicalclassification
Acute phase. a suspected case was defined as an individual with
> 7 days of fever accom-
panied or not by hepatomegaly or splenomegaly. The patient
was considered with acute Chagas
disease if additionally to symptoms tested positive by
parasitological tests (Strout, micro-strout,
blood thick smear, or hemoculture) [15] or presented positive
28. results to two serological tests
over the course of the following weeks [30,31]. The patients
were classified as negative to Cha-
gas disease otherwise noted.
Chronic phase. individuals without criteria for acute phase but
with clinical or epidemio-
logical suspicion of Chagas disease. The patients were
confirmed as positive T. cruzi infection
when tested positive to two serological tests (IFA, ELISA
and/or HAI). It was then classified as
chronic undetermined (when no evidence of signs or symptoms
of heart complications were
evinced) or chronic determined otherwise.
The risk factors classification was conducted through a survey
applied to each of the patients
included in the study. A series of questions were asked such as
the place of birth, knowledge of
vector insects, blood donations and/or organ transplantation,
housing type and presence of
cardiac symptoms based on previous evaluated questionnaires
(Survey 1) [32]. Patients whose
serological tests were negative were classified into two groups
according to the presence or
absence of risk factors. The patients, who had one or more risk
factors, were categorized as
"negative with risk factors" and those patients that did not have
any risk factors were catego-
rized as "negative without risk factors".
Laboratorytests
Parasitological methods. The direct parasitological methods
were performed (Strout,
micro-strout, blood thick smear, or hemoculture) according to
29. the methodology described by
Table 1. Generalcharacteristicsofpatientsincludedinthestudy.
General characteristics Acutephaseb N = 86 Chronicphasec N =
622
Positive Negative Positive Negatived
Patientsnumber(N) 708 71 15 481 141
Age,median(Q1-Q3)a 48 (47–49) 31 (26–35) 27 (23–30) 51 (50–
53) 37 (39–41)
Sex, n (%)
Female 428 (60.4) 26 (36.6) 8 (53.3) 313 (65.1) 60 (42.5)
Male 280 (39.6) 45 (63.4) 7 (46.7) 168 (34.9) 81 (52.4)
a Age in years
b Positive patientswere those who had positive
directparasitological tests, symptomatology and/orserological
tests. Negative patientscomprise a group of
febrilepatientswith negative serologyfor Chagas disease and
diagnosedwith dengue.
c Positive patientswere those who had two positive serological
tests and negative patientswere those with two negative
serological tests.
d Twenty-nine were negative without risk factor and 112
negative with risk factor
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Freilij et al., 1983 [33]. The results were considered positive
when morphology compatible with
the T.cruzi was observed. All samples were analysed without
knowledge of the clinical status or
other test.
Serological tests. Enzyme-linked immunosorbent assay
(ELISA), immunofluorescence
antibody assay (IFA) or hemaglutination-inhibition assay (HAI)
were originally standardized
at the National Health Institute [34] with T. cruzi strains
belonging to TcI. All serological tests
were conducted in duplicate and positive and negative controls
were used for each assay.
ELISA test was considered as positive when absorbance was
�0.300, IFA when titres were �1/
32 and HAI when titres were �1/32.) (S1 Appendix). All
samples were analysed without
knowledge of the clinical status or other tests. The
indeterminate results in the serology tests
(ELISA and IFI) were resolved by use of HAI test.
Molecular diagnostic tests. 10 mL of blood samples were
collected and stored with equal
volume of Guanidine Hydrochloride 6M, EDTA 0.2 M buffer,
pH 8.00 (GEB) and subsequently
stored at 8°C. 5mL of serum was frozen at -70°C as described
elsewhere [25,35]. 300 μL aliquots
of GEB were employed and 5μL of IAC plasmid (40pg/μL) were
added as internal control. The
31. samples were submitted to DNA extraction using the High Pure
PCR Template Roche kit
according to Duffy et al., 2013. Conventional PCR (cPCR) and
multiplex quantitative PCR
(qPCR) for detection of satellite DNA of T. cruzi and IAC
plasmid DNA were performed as
reported elsewhere [23,26]. The qPCR test was considered
positive when the amplification
exceeded the threshold of fluorescence 0.01 and cPCR when
was observed a DNA fragment of
166 bp in the electrophoresis. The positive samples for satellite
nuclear PCR (qPCR and cPCR),
were confirmed by kPCR. Parasitic loads by qPCR were
measured as parasite equivalents per mL
according to Moreira et al., 2013, using a TcI strain as standard
curve (MHOM/CO/01/DA] [22].
All samples were analysed without knowledge of the clinical
status or other tests (S1 Appendix).
DTUs discrimination. PCR was performed using five different
molecular markers aimed
at detecting the six DTUs and the two subdivisions of TcI
previously described by other authors
(TcIDom and TcI sylvatic) as recommended elsewhere [36–41]
(S1 Appendix and S1 Fig).
Statisticalanalysis
Operating characteristics of the molecular tests were estimated
by comparing against standard
diagnosis (described above). Sensitivity, specificity, positive
(+LR) and negative likelihood ratio
(LR-), predictive values (PV), diagnostic precision (DP), Area
under the curve (AUC), and
Kappa index (K) were estimated for each phase of the disease
(acute and chronic), the clinical
stage of chronic patients (determined and undetermined) and
32. according to DTUs and TcI
genotypes identified (TcI sylvatic/TcIDom) (S2 Appendix).
Results are presented as percent-
ages, with corresponding 95% confidence intervals (95% CI).
Additionally, operational capabil-
ities in chronic patients were calculated in two ways: the first
including negative patients
without risk factors since they are the true negative and the
second including all the negative
patients (with and without risk factors). Due to over dispersion
of parasitic loads, medians and
quartiles are presented. Comparisons are based on Mann-
Whitney test between clinical phases,
chronic clinical stages and the different T. cruzi DTUs and
genotype groups identified. A p
value at <0.05 was considered as statistically significant. All
analysis was performed in Stata:
Data Analysis and Statistical Software version 12.
Results
Generalcharacteristicsof the patients included in the study
Overall, 985 patients were included, 872 suspected of chronic
and 113 of acute infection. Gen-
eral demographic characteristics are shown in Table 1. Out of
the initial potential participants,
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http://www.stata.com/
http://www.stata.com/
33. 27 and 129 were excluded for incomplete samples to perform all
analysis from the acute and
chronic groups, respectively and 121 from the chronic group
due to absence of clinical informa-
tion (Fig 1). The inclusion of patients was prospective, whereas
the sample collection was both ret-
rospective (for the period 2004–2011) and prospective (for the
period 2012–2015). This means
that for the retrospective component the samples were part of
the repository. The repository con-
sists of 144 samples, collected between 2004 and 2011, and
corresponds to serum samples stored
at (-80°C). In these samples, serological tests were repeated and
it was found that the results were
the same that they had been reported at the time of collection of
samples and molecular tests were
performed. The prospective component consists of 564 samples,
collected in the period between
2012 and 2015, and maintained in guanidine hydrochloride
solution until processing.
In patients from the acute phase, the qPCR test was positive in
95.7% of the patients and
cPCR in 84.5%. In patients from the undetermined chronic
phase, qPCR was positive in 68.0%
of the cases and in 55.4% by cPCR. In the cardiac chronic
phase, qPCR positivity was 59.1%
and 58.6% by cPCR. The positive samples for satellite nuclear
PCR (qPCR and cPCR), were
confirmed by kPCR. In patients that were negative by serology
but with risk factors cPCR
(2.6%) and qPCR (3.6%) were positive. In febrile and negative
patients without risk factors
both tests were negative in all samples. In all samples analyzed
we detected the internal amplifi-
cation control for both cPCR and qPCR, the average Ct value in
34. all samples tested was 21.
Fig1. Algorithmfor
selectionandclassificationofpatients.Therewere selected 708
patients,71 in acutephase, 15 febrilenegatives, 481 in chronic
phaseand 141 negatives. *RF:Risk Factor.
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Operatingcharacteristicsof molecularmethodsvs
standarddiagnostic
tests
The operating characteristics including all negatives patients of
chronic phase (Negatives with
and without risk factors) are presented in Tables 2 and 3.
Performance of qPCR was higher compared to cPCR in both
acute (AUC 0.98 vs 0.92) and
chronic phase including only negatives with risk factors (0.82
vs 0.78) (Fig 2). Likewise, the per-
formance was significantly higher in acute compared with
chronic phase and in overall a speci-
ficity higher than sensitivity particularly in chronic phase
(Tables 2, 4 and 5).
T.cruziparasitic loads and clinicalphase
Parasitic loads were determined in samples that tested positive
by qPCR. Significantly different
median values were detected in acute (4.69 parasite
37. (62.3–69.6)
LR+ Undefined 22.6 (13.82–37.09) 26.68(13.8–51.5)
LR- 0.04 (0.02–0.1) 0.15 (0.13–0.18) 0.37 (0.36–0.37) 0.44
(0.43–0.45)
Kappaindex 0.89 (0.7–1.1) 0.62 (0.5–0.9) 0.43 (0.36–0.49) 0.36
(0.29–0.42)
AUC 0.98 (0.91–0.99) 0.92 (0.88–0.96) 0.81 (0.77–0.84) 0.77
(0.74–0.81)
PPV: Positive predictive value; NPV: Negative predictive value;
DP: diagnostic precision; LR+: positive likelihood ratio;LR-:
negative likelihood ratio. N =
(Positive gold standard/ total assayed). When the specificity is
100% the positive likelihood ratio is undefined.
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Fig2. ROC
curvesofmoleculartestsinclinicalphasesofChagasdisease.A.
AcutephaseB. ChronicphaseC. Chronicundetermined phase
D. Chronicdeterminedphase.
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Molecular testsperformanceaccordingtoT.cruziDTUs and
clinical
phase
In samples that tested positive (n = 407) by cPCR, the DTUs
TcI-TcVI and TcI (TcI Dom, TcI
Sylvatic) were evaluated. The distribution of DTUs was 74.2%
for TcI, 17.2% for TcII, 1.48%
for TcIII, 0.5% for TcV and 6.7% for mixed infections. For the
latter seven different combina-
tions were identified: TcIDom/TcII/TcV, TcIDom/TcII,
TcIDom/TcISylv , TcIDom/TcISylv/
TcII, TcIDom/TcISylv/TcIII, TcIDom/TcIV, TcISylv/TcII. With
respect to TcI, the genotyping
was feasible in 290/302 samples. Out of them, 28.7% were
classified as TcI Sylvatic and 71.4%
as TcIDom. The median load parasitic value for TcII (4.68
parasite equivalents/mL) was signif-
icantly different to the one for TcI (2.87 parasite
equivalents/mL) and TcIII (1.72 parasite
equivalents/mL) (Fig 4).
The genotype distribution according to clinical phase evidenced
that TcIDom was sig-
nificantly more frequent in chronic phase compared with acute
phase (Table 6). The oper-
ating characteristics of molecular tests for the different
genotypes were calculated,
observing that the sensitivity for identifying TcII was slightly
higher than for TcI, mainly
39. for qPCR (S1 Table). The median parasitic load for TcIDom
was significantly higher (2.58
parasite equivalents/ml) compared with TcI Sylvatic (0.76
parasite equivalents/ml) in
chronic phase (Fig 5).
Discussion
Operatingcharacteristicsof molecularmethodsagainststandard
diagnostic tests
The main limitation involved in this study is the fact that there
is not a gold standard test for
all clinical phases of Chagas disease. Particularly for chronic
phase, the best comparators are
serological tests but these techniques measure the immune
response and not the relative pres-
ence of the parasite. This particular situation impacts the
evaluation of new diagnostic tests.
This is reflected mainly in the kappa index (Tables 2 and 4) that
presented very low values in
the undetermined and determined chronic phases. Unfortunately,
it has not a simple solution
and more understanding of the course of the infection is still
needed.
Table 4. Operating characteristicsofmolecular
testsinchronicphaseofChagasdiseaseincluding
onlynegativeswithoutriskfactors.
Operatingcharacteristics ChronicphaseN = (481/510)
qPCR(95%CI) cPCR(95%CI)
Sensitivity 64.2 (59.9–58.4) 56.8 (52.3–61.1)
Specificity 100.0(88.3–100.0) 100 (88.3–100.0)
40. PPV 100.0(98.8–100.0) 100.0(98.6–100.0)
NPV 14.4 (10.2–19.9) 12.2 (8.7–17.0)
DP 66.3(62.1–70.2) 59.2 (54.9–63.4)
LR+ Undefined
LR- 0.36 (0.35–0.36) 0.43 (0.42–0.44)
Kappaindex 0.17(0.1213–0.218) 0.13 (0.09–0.17)
PPV: Positive predictive value; NPV: Negative predictive value;
DP: diagnosticprecision; LR+: positive
likelihood ratio;LR-: negative likelihood ratio. When the
specificity is 100% the positive likelihood ratio is
undefined. N = (Positive gold standard/ totalassayed)
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Table 5.
Operatingcharacteristicsofmoleculartestsinchronicphases(undete
rminedanddetermined)ofChagasdisease includingonlynega-
tiveswithoutriskfactors.
Operatingcharacteristics ChronicundeterminedphaseN = 278/307
42. loadsinpatientswithChagasdisease.Distributionof parasitic load
and medianson the
basis of theclinicalphases. Theoutlierswere removed fromthe
graph for convenience. * p < 0.05 ** p<0.01 *** p < 0.001.
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Fig4. Comparativeanalysisofparasitic
loadsforDTUs.Distributionof parasitic load and medianson
thebasis
of theT.cruziDTUs. For convenience the outlierswere removed
for the graph. * p < 0.05 ** p<0.01 *** p < 0.001.
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Table 6.
FrequencyofDTUsandTcIgenotypesfromclinicalphasesofChagasd
iseasepatients.
DTUs Clinicalphases P value
Acute Chronic
N = 68 N = 332
N (%) (95%CI) n (%) (95%CI)
TcI 54 79.4 69.3 88.9 241 72.6 67.8 77.4 0.25
43. TcII 6 9.0 2.0 15.9 64 19.3 15.0 23.5 0.04
TcIII 4 6.0 0.2 11.7 2 0.6 0.2 1.4 <0.001
TcV - - - - 2 0.6 0.2 1.4 0.53
Mixed 4 6.0 0.2 11.7 23 6.9 4.2 9.7 0.15
TcI Genotypes N = 48 N = 235
TcI Sylvatic 40 85.1 74.8 95.4 42 17.9 12.9 22.8 <0.001
TcI Dom 8 16.6 4.6 25.2 193 82.1 77.2 87.0 <0.001
DTU: Discrete Unit Typing; bold text: p value at <0.05
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The results obtained for the molecular diagnosis in acute phase
were optimal in terms of
sensitivity for both qPCR (95.7%; 95%CI: 88.3–98.5) and cPCR
sensitivity (84.5%; 95%CI:
74.3–91.2), and same specificity. Although the results are
showing a potential superior perfor-
mance of the sensitivity of qPCR compared with cPCR, this
difference needs a cautious inter-
pretation. This might be explained due to the fact that detection
by qPCR increases the
sensitivity and specificity because of the hybridization of the
Taqman probe in the amplicon,
whereas in the case of the cPCR it requires a considerable
44. amount of amplicon so that it can be
observed in agarose gels [25,26] In addition, the confidence
intervals were slightly overlapped,
meaning that there is some indication of this difference but it is
not statistically significant, so
not definitive. The performance of the molecular tests in the
acute phase is explained because
there are large numbers of parasites, for example in cases of
reactivation in immunosuppressed
patients and in oral outbreaks. The values obtained for LR
evinced the high probability that
positive results correspond to diseased patients (LR+) and the
low probability that the diseased
patients present negative results (LR-). In addition, the DP was
very optimal specifically for
qPCR test confirming that this molecular test is very useful for
the diagnosis in the acute phase,
considering that the direct diagnosis is complex when the
parasitemia is low (As is the case of
the acute patients detected more than a month after the infection
where the parasitemia nor-
mally begins to decrease due to the control of the immune
response) and are required many
tests for the confirmation of the acute cases (direct tests,
serology tests and clinical informa-
tion). Regarding the predictive power of molecular tests in the
acute phase, these tests are very
good predictors of the disease presence when positive results
are obtained (PPV) but their per-
formance as predictors of absence of the disease are less (NPV).
However, it is worth noting
that the predictive values depend on disease prevalence in the
evaluated population.
The analysis of operational capabilities in the chronic phase was
conducted in the first
45. instance including only negative patients without risk factors or
true negatives. For the chronic
Fig5. Comparativeanalysisofparasitic
loadsforTcIGenotypesintheclinicalphases.Distribution of
parasitic load and medianson the basis of theTcIgenotypesin
theacuteand chronicphases. For convenience the
outlierswere removed for thegraph. * p < 0.05 ** p<0.01 *** p
< 0.001.
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phase, qPCR sensitivity was 64.2% and 56.8% for cPCR and in
concordance with previous
reports obtained by qPCR that have shown sensitivity ranging
from 60–80% and 20–70% for
cPCR [22–24,26,28,42]. These sensitivity results may be due to
low and intermittent parasitic
loads during chronic phase.
The performance of qPCR was better than cPCR in the chronic
undetermined phase, while
that was very similar between the two tests in the determined
chronic phase (Tables 3 and 5).
The discriminative power of the two molecular tests was
acceptable in the chronic phase. For
qPCR, the AUC and DP values obtained (Tables 3 and 5) were
better for the undetermined
phase than for determined phase. The differences between
46. undetermined and determined
phases for qPCR of the chronic phase can be explained by the
natural course of the disease, in
which the parasitic load decreases while increases the infection
time. This is supported by sev-
eral studies showing that there is no relationship between the
evolution of the cardiac form of
the disease and parasitemia but it declines with time as
observed in this study [43,44]. Also,
some studies show that cardiac form is mainly related to
different types of strains, increased
parasitemia, reinfection or immune system disorders in chronic
patients [45,46]. In the cPCR
AUC values were the same for both phases, while the value of
DP was best for the determined
phase. Possibly, this is because the detection limit of the cPCR
is lower than qPCR, for this rea-
son the cPCR behaves similarly in the two phases. In the two
stages of the chronic phase, there
is a high probability that patients with negative results in the
molecular tests have the disease
(LR-) and these tests are not good predictors of the absence of
the disease (NPV) (Table 5).
Therefore, the use of molecular methods as diagnostic tests is
not appropriate due to the better
performance displayed by serology. The probability that the
results are positive is high in dis-
eased individuals with respect to healthy individuals (LR +) and
the molecular tests are excel-
lent predictors of the presence of disease (PPV). Thus, these
tests could be used in situations in
which the diagnosis is doubtful, allowing the confirmation of
the parasite in diseased patients,
which is of great importance for example when monitoring
etiological treatment. However, it
is necessary to improve the sensitivity, which can be performed
47. by analysing serial samples for
each patient as seen in some studies in which such sensitivity
improved from 69.2% to 85.2%
with the addition of a second sample or conducting DNA
extraction from a larger volume of
the sample [47,48].
In addition, the operating capabilities of patients in chronic
phase were calculated including
all negatives by serology with and without risk factors (Table 1,
N = 141). It was observed in
the group of negative patients with risk factors a positivity of
2.6% (3 patients) by cPCR and
3.6% (4 patients) by qPCR, possibly due to an
immunosuppression issue in these patients pre-
venting the detection of antibodies or infection. Three patients
are from the department of
Casanare, which is an endemic area, and five patients had less
than 24 years of age suggesting a
recent infection. Also, all patients reported to know the vectors
and have lived during his/her
childhood in homes with features such as thatched or
‘barheque’, floor or wood and/or tread
walls of earth, wood or ‘barheque’. Two of the seven patients
that were negative by serology
and had risk factors, whose ages were 36 and 51 showed the
presence of symptoms at cardiac
level. In this group of 7 patients, 4 presented the ELISA
absorbance values greater than 0.200
and 4 detectable titles in the IFA (1/8 and 1/16).
As the operating capabilities calculated including all negative
patients, a small percentage of
decreased specificity in the two platforms was observed (S3
Appendix). The positivity of these
serologically negative patients that generated the decrease can
48. probably be explained because
cases of recent infection or patients with some form of
immunosuppression that has generated
the absence of detectable antibodies. In fact, in the group of
acute patients, 4 patients whose
serology was negative showed positive PCR, in these patients
the detection was achieved by
direct parasitological methods. Regarding the molecular
techniques, given that in all PCR runs
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were included negative controls including reagents controls, a
plausible contamination with
parasite DNA is discarded. Significantly, the DP and AUC
values showed no obvious changes
unlike the values obtained for the NPV and the Kappa index, in
which there was a marked
increase. However, the changes obtained do not change the
interpretation of the usefulness of
the test in the clinical setting, but can show that there are few
cases where serological tests may
have false negatives as noted previously using cPCR by
Ramirez et al., 2009 [23]. Even though
serological tests are considered the best current option for the
diagnosis of Chagas disease, in a
meta-analysis of high quality tests their sensitivity has been
estimated at 90% [49]. Given this,
we believe that an improvement of diagnostic tests for Chagas
disease is needed for both serol-
ogy and PCR techniques. An appropriate use of the comparator
49. as gold standard and the inclu-
sion of different phases of the disease are crucial to understand
the utility of different
diagnostic tests.
To our knowledge, this is the first study to include statistical
calculation of the sample,
which allowed the analysis of operating characteristics of the
molecular tests in all clinical
phases of Chagas disease. In addition, this study is the first in
analysing the two PCR platforms
(qPCR and PCR) for the same target (stDNA) in patients from
all clinical phases of Chagas dis-
ease. The conventional technique was included, due to the vast
use of this technique in the
diagnosis and its ease implementation in laboratories with
restricted equipment (a Real Time
PCR machine is not available) [23,24,28]. Lastly, acute patients
had a less median age than
chronic phase patients and in turn the largest number of acute
cases are male. This possibly is
because economic activity in endemic areas is developed by
males that assist to the field and
this facilitates direct patient contact with the vector and
therefore with the parasite. On the
other hand, females ratio and the median age were higher in
chronic phase patients that are
usually detected by screening blood banks or present cardiac
abnormalities in chronic phase,
then the detection occurs at a greater age. Additionally, in
Colombia most blood donors are
women facilitating their diagnosis.
T.cruziparasitemia,DTUs and clinicalphases
Regarding the parasitemia, it is observed that the median
parasitemia was higher in acute
50. patients compared to chronic phase, which is expected given the
dynamics of parasitemia in
the disease [25,26]. As for the group of chronic patients, the
herein reported median of parasi-
temia is similar to those previously reported for Colombia
[22,26]. In addition, the difference
in medians between cardiac chronic and undetermined chronic
stages was statistically signifi-
cant, being higher in the undetermined chronic phase unlike the
findings described by Ramirez
et al, 2015 [26], in which statistically significant difference was
not detected. However, our
results are in accordance with the natural history of the disease
where parasitic loads decrease
with the chronicity of the infection and this is probably
associated with the type of strain and/
or the immune response [2].
The DTU with highest frequency was TcI, both in acute and
chronic patients, consistent
with findings previously reported in Colombia [8,39,50,51].
Followed by TcII most often
detected in chronic than acute patients. These findings are
congruent due to the predominance
of TcII in domestic cycles of transmission for the case of
Colombia [50]. Regarding the parasitic
loads of the DTUs detected, we observed that TcII had higher
median parasitemia than other
DTUs, consistent with the number of copies that has been
reported in the DNA nuclear satel-
lite region being higher for TcII than for TcI [52–54]. These
findings highlight the importance
of using the most representative DTU to generate the standard
curves for quantification
[22,25,26]. In addition, in murine models TcII shows higher
parasitemias than TcI when per-
51. forming individual and mixed infections [55].
Diagnosis and Genotyping ofT.cruzi in Acuteand ChronicPhases
PLOS NeglectedTropical Diseases |
DOI:10.1371/journal.pntd.0004997 September 20,2016 14 / 20
In this study, acute cases are likely caused by vector
transmission and possible oral route. In
most of the cases TcI (TcI sylvatic), TcII and TcIII infection
was observed. These findings are
consistent with previously documented reports for acute patients
where DTUs associated with
the sylvatic cycle of transmission were depicted [4,5,40,51,56–
61]. An interesting finding was
the detection of TcV in the patients surveyed. This DTU has
been already reported in dogs and
Rhodnius prolixus from eastern Colombia but this would be the
first report of TcV human
infection in the country [50]. It is necessary to conduct further
studies to understand the host-
parasite associations of this foreseen DTU in patients from
northern areas of the continent. It
is well known that TcV infection is endemic in Bolivia, Brazil
and Argentina but in Colombia
is a novel case that requires further investigation; in fact high-
resolution markers have been
applied to the few isolates of Colombian TcV showing a tailored
hybrid profile suggesting a
Pan-American import from south America [62]. The DTU TcVI,
is mainly detected in the
South Cone of Latin America. Normally associated with
megavisceral syndromes and some
cases of congenital heart disease [4]. In Colombia, TcVI has
52. been very rare and almost infre-
quent. In fact it is limited to a report in which was detected in
humans and R. prolixus isolates
(4% and 1.4% respectively). In addition, in different studies
with a considerable number of
patients conducted in Colombia it was not detected, confirming
the low prevalence of the DTU
in the country [39,51,63].
Recently, it has been highlighted the emergence of a genotype
named as TcIDom and associ-
ated to human infection and domestic transmission cycles via
different molecular markers
[5,6,8,64–66]. Other studies have shown the presence of TcI
Sylvatic genotype in tissue and TcI-
Dom in bloodstream of patients with Chagas cardiomyopathy
[41]. In murine models was
observed that TcIDom produced high parasitemia and low tissue
invasion, a process that allows
an adaptation to the host prolonging its permanence and likely
generation of chronicity, opposite
process to what happened with the TcI sylvatic strains [67]. In
accordance with these previous
findings, our results show that in chronic patients the frequency
and parasitemia of TcIDom geno-
type were significantly higher in chronic patients than in acute
patients, supporting the hypothesis
that this genotype may be related to chronicity in patients with
Chagas cardiomyopathy.
In conclusion, the molecular diagnostic tests are becoming a
precise tool to complement the
standard diagnostic methods for Chagas disease. This study
shows that in general qPCR has a
better performance than cPCR. Also, the results confirm that
PCR is highly specific for both
53. acute and chronic clinical phases, whereas sensitivity is
acceptable for acute phase but still very
low for chronic patients. This situation could be partially
explained by the higher parasitic
loads detected in acute phase and the intermittent nature of the
parasite release to the blood-
stream in chronic phase. We explored for the first time in a
large cohort of Chagas disease
patients the DTU parasitemia and the natural course of
infection. This type of studies is
required in Latin-America for a better understanding of disease
progression and molecular epi-
demiology of Chagas disease. This makes PCR a potential tool
for its use in acute phase diagno-
sis in a routine basis, and potentially for determining
aetiological treatment failure when tests
positive but not substantially useful when tests negative and
these results must be interpreted
cautiously as in the clinical trials previously published [21,68].
Further research is needed to
improve the sensitivity of this test and the mandatory
deployment of new diagnostic tests.
SupportingInformation
S1 Fig. Algorithm for genotyping of T. cruzi DTUs. Molecular
characterization of T.cruzi by
five molecular markers and genotyping of TcI DTU in two
genotypes TcI Dom and �TcI Sylv:
TcI Sylvatic.
(JPG)
Diagnosis and Genotyping ofT.cruzi in Acuteand ChronicPhases
PLOS NeglectedTropical Diseases |
DOI:10.1371/journal.pntd.0004997 September 20,2016 15 / 20
54. http://journals.plos.org/plosntds/article/asset?unique&id=info:d
oi/10.1371/journal.pntd.0004997.s001
S1 Table. Operating characteristics of molecular test for DTUs
and genotypes TcI.
(DOC)
S1 Appendix. Methodology of reference tests employed in the
study.
(DOCX)
S2 Appendix. Detailed methodologyof the molecular tools
employed in the study.
(DOC)
S3 Appendix. Sensitivity and specificity calculations.
(DOC)
S4 Appendix. STARD. Standards for Reporting of Diagnostic
Accuracy Checklist.
(DOCX)
S5 Appendix. Research protocol. Project: Characterization of a
cohort of patients with Chagas
disease, its etiological treatment, adverse events and therapeutic
response.
(PDF)
Acknowledgments
Parasitology group and Red Chagas Colombia, National
Institute of Health, Colombia.
AuthorContributions
Conceived and designed the experiments: CH ZC JDR.
55. Performed the experiments: CH CF CL.
Analyzed the data: CH ZC MO CV PZ JDR.
Contributed reagents/materials/analysis tools: ZC JDR.
Wrote the paper: CH ZC JDR.
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74. Keywords
lifetime socioeconomic position, growth trajectories, cognitive
and
emotional function, adult health, life course conceptual
frameworks,
intergenerational influences
Abstract
Maturation of long-running birth cohort studies has fostered a
life
course approach to adult health, function, and disease and
related to
conceptual frameworks. Using broad concepts of human
development
including physical, cognitive, and emotional function, birth
cohorts
provide insights into the processes across the life course and
between
generations that link to adult outcomes. We discuss findings on
the
determinants and health consequences of lifetime trajectories of
body
size, cognitive and emotional function, and socioeconomic
position.
Findings from the studies suggest that, for some adult health
outcomes,
explanations will be incomplete unless exposures and processes
from
across the life course are taken into account. New birth cohort
studies
are poised to delineate further the nature and timing of life
course
relationships in contemporary generations of children.
78. INTRODUCTION
Research on the developmental origins of adult
disease is broad in scope, embracing many
scientific disciplines, exposures, and outcomes.
Such research recognizes the potential for
influences on early-life development to lead to
changes that impact on disease risk decades later
in adulthood. This developmental perspective
is long-established within some disciplines, for
example, those concerned with emotional and
cognitive function, but for other disciplines
it is relatively recent. A major impetus to
developmental origins research was provided
in the early 1980s by a series of studies linking
low birth weight, as a proxy for poor prenatal
growth, to increased risk of chronic diseases
in adulthood, including cardiovascular disease
(CVD) and diabetes (the fetal origins hypothe-
sis) (2). Earlier in the past century, investigators
were interested in early environmental in-
fluences on the individual’s constitution that
might affect later mortality risk (52). Nonethe-
less, the fetal origins hypothesis represented a
shift in emphasis for research on adult chronic
disease, which had focused largely on adult
lifestyles. Emerging research over the past three
decades has led to a convergence of evidence on
the wide-ranging effects of early environment
and associated development for later health
outcomes (50, 99) and to establishment of
the International Society for Developmental
Origins of Health and Disease in 2003.
Birth cohort studies established some
79. decades ago have been well positioned to
TRAJECTORIES
“A trajectory provides a long-term view of one dimension of an
in-
dividual’s life over time. These may be social states (such as
work,
marriage, socioeconomic position), psychological states (such
as depression) or physiological states (such as lung function).
Implicit is the idea of a normative trajectory around which in-
dividuals deviate” (52). For health function, a trajectory may in-
clude a period of gain to a peak followed by a period of decline
(e.g., for lung function).
investigate developmental origins hypotheses,
and in turn, these hypotheses have provided a
stimulus for the establishment of new cohorts.
There are now several birth and infancy
cohorts in Britain, New Zealand, Finland,
and elsewhere, including those established in
the past few years and longer-running studies
with follow-up in some instances of five or
more decades. Basic details of some of these
studies are given in Table 1; the list is far from
comprehensive but illustrates the range of birth
dates, length of follow-up, and original study
purposes. Both younger and older studies alike
have tended to collect information on parental
characteristics and social and family back-
ground, as well as conditions during pregnancy
and in early childhood. In addition, many older
studies have assessed the physical, cognitive,
behavioral, and emotional development of
their participants and collected information on
social destinations, lifestyles, and other putative
80. influences on later disease risk. In recognition
of the importance of charting early develop-
mental milestones and trajectories (see sidebar
on Trajectories), some younger cohorts have
been instigated during pregnancy rather than at
or soon after birth and also have more frequent
contacts early in childhood than did some older
studies. Longer-running studies have been able
to investigate influences across developmental
domains (physical, cognitive, emotional) in
relation to health in later life, and with infor-
mation collected at different life stages, these
maturing birth cohorts have fostered a life
course approach to adult disease. The objective
of a life course approach in epidemiology is
to establish how social and biological factors
operating at different stages of life and across
generations contribute to the development of
adult health and disease over time (52). With
its consideration of different ages, life course
research seeks to understand influences of
early-life exposures and development on later
disease outcome and the processes occurring
in the intervening years of life that link them.
Thus, life course epidemiology extends the de-
velopmental origins of adult disease perspective
by focusing attention on potentially sensitive
8 Power · Kuh · Morton
A
nn
u.
R
84. Follow-ups
(timing)
N at last
sweep
(%)
Initial reason
for/focus of study
National Survey of
Health and Devel-
opment/Britain
(54, 108)
1946 Socially stratified
sample of singleton
babies born in one
week, March 1946,
to married women
5,362 Birth, 2, 4, 6, 7, 8, 9,
10, 11, 13, 15, 19,
20, 22, 23, 26, 31,
36, 43, 47(F),
48(F), 49(F), 50(F),
51(F), 52(F), 53,
54(F), 60–64 years
2,661 To consider cost of and
care in pregnancy and
childbirth. Social class
differences in
maternal and child
mortality and
morbidity
85. National Child
Development
Study/Britain (77)
1958 All born in one
week, March 1958
17,638 Birth, 7, 11, 16, 23,
33, 42, 45, 46,
50 years
9,790 To identify social and
obstetric factors
linked to stillbirth and
neonatal death
Aberdeen Children
of the 1950s
Study/Britain (62)
1950–
1956
All primary-school
children in
Aberdeen in 1962
12,150 Perinatalb (linked),
7, 9, 11,
45–50 years
7,655 To understand
predictors of low
childhood cognition
86. Northern Finnish
Birth Cohort
Study/Finland (87)
1966 Live born,
European descent,
with expected birth
dates in 1966, Oulu
and Lapland
(northern Finland)
12,058 Pregnancy, birth,
1 year, 14 years,
31 years
8,690 To examine risk factors
for childhood
mortality and
morbidity in a
geographically
defined population
1970 British Birth
Cohort
Study/Britain (20)
1970 All born in one
week, April 1970
16,571 Birth, 5, 10, 16, 26,
30, 34, 42 years
9,656 at
34 years
To examine the social
87. and biological
characteristics of
mothers in relation to
neonatal morbidity
Dunedin
Multidisciplinary
Health and
Development
Study/New
Zealand (98)
1972 All births in
Dunedin March
1972–April 1973
enrolled at 3 years
1,037 3, 5, 7, 9, 11, 13, 15,
18, 21, 26, 32 years
972 To conduct a
longitudinal
population-based
multidisciplinary
study of child health,
development, and
behavior
Christchurch
Health and
Development
Study/New
Zealand (24)
1977 Children born
April–early August
88. 1977 in
Christchurch
1,265 Annually from birth
to 16, 18, 21, 25,
30 years
934 To conduct a
longitudinal birth
cohort focused on
child health and
development
Avon Longitudinal
Study of Parents
and Children
(ALSPAC)/England
(7)
1991–
1992
Offspring of all
pregnant women in
the county of Avon,
estimated delivery
date April 1,
1991—December
31, 1992
15,247
eligible
preg-
nancies
en-
rolled
89. 68 time points, birth
to 18 years
7,729c To investigate
modifiable influences
on child health and
development
(Continued )
www.annualreviews.org • Life Course Research on Adult
Disease 9
A
nn
u.
R
ev
. P
ub
li
c
H
ea
lt
h
20
13
92. on
ly
.
PU34CH02-Power ARI 12 February 2013 19:27
Table 1 (Continued )
Cohort
name/country
Year of
birth Selection/design
N at
baseline
Follow-ups
(timing)
N at last
sweep
(%)
Initial reason
for/focus of study
Southampton
Women’s
Survey/England
(44)
1998–
93. 2007
Births to recruited
12,583
prepregnant
women
3,156 Prepregnancy,
pregnancy
(multiple),
6 months, 1, 2, 3,
4, 6, 8 years
1,477 at
6 years
To understand
perinatal and early life
determinants of
children’s growth and
development
Millennium Cohort
Study
(MCS)/United
Kingdom (14)
2001 Nationally
representative
sample across
United Kingdom
recruited during
infancy
19,244 9 months, 3, 5, 7,
11 years
94. 15,590 at
7 years
To understand the
biological and
environmental
determinants of
contemporary child
development
a Note: This list of studies is not exhaustive. Birth cohorts
documented have collected perinatal information and have
existed for long enough to provide
sufficient longitudinal data to inform the areas addressed in this
article. The success of older cohorts has provided the impetus
for many new birth cohort
studies begun around or after the turn of the millennium. Newer
studies include those in the European Child Cohort Network
(EUCCONET), as well as
studies in Australia (Growing Up in Australia—LSAC) and New
Zealand (Pacific Island Families Study and Growing Up in New
Zealand). EUCCONET
includes the Norwegian Birth cohort (MoBa), Danish National
Birth cohort, Generation R Study (The Netherlands), Born in
Bradford (United
Kingdom), Millennium Cohort study (MCS), Growing Up in
Scotland (GUS), Growing Up in Ireland (GUI), ELFE (France)
and will include a newly
planned UK study.
b The Aberdeen Children of the 1950s Study is included here
because it has birth information for the 14,932 children who
were part of this cohort.
However, they were enrolled between ages 5 and 11 years (in
1962), and perinatal data were linked for the cohort at that time.
c Completing ≥1 item during the transition to adulthood.
95. periods in childhood and adolescence as well
as in the prenatal period. It extends the adult
lifestyle theories of chronic disease by focusing
attention on the early acquisition of lifestyle and
its cumulative effects. It extends social causation
theories of adult chronic disease by drawing
attention to the impact of the socioeconomic
environment in childhood as well as adulthood.
It also extends both developmental origins and
adult theories of disease causation by consider-
ing the joint action of early and later exposures.
With an increasing number of studies and
duration of follow-up, birth cohorts are now
charting new territories. Some recently estab-
lished cohorts are focusing on understanding
early development in the wider neighborhood
and societal context (69). Older birth cohort
studies, often with decades of information, are
examining influences on the population range
of functional capacities and disease risk into
later adulthood, and an agenda on life course
influences on aging is already emerging. Many
birth cohorts now incorporate genetic factors
and are contributing to the discovery of genetic
variants associated with important phenotypes
(e.g., obesity) through consortia for genome-
wide association studies. Moreover, the cohorts
offer the prospect of advancing understanding
of (epi)genetic influences on developmental tra-
jectories and how these relate to the potentially
modifiable environmental context.
At a time when birth cohort studies are
96. evolving to address a range of social, economic,
and health questions, it is timely to critically
review their contributions and identify future
challenges. This article does not purport to
provide a comprehensive summary of the vast
literature from these cohorts, but it consid-
ers some main themes of relevance to public
health. Specifically, we consider examples of
where birth cohorts have stimulated thinking
about the life course frameworks that might
guide research on pathways to adult disease
and where, in this regard, they have added
new knowledge. Evidence from the studies has
been informative on many important themes,
10 Power · Kuh · Morton
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PU34CH02-Power ARI 12 February 2013 19:27
SEP: socioeconomic
position
e.g., on the natural history of some condi-
tions, long-term outcomes of specific preg-
nancy exposures/characteristics, and determi-
nants of healthy lifestyles, but we do not cover
these themes in any detail here. Instead, we
summarize some of the work on the follow-
ing in relation to adult function and disease:
lifetime socioeconomic position (SEP), lifetime
growth trajectories, and cognitive and emo-
tional development at different life stages. For
each of these research areas the birth cohorts
have contributed a substantial body of empir-
ical evidence. With the exception of lifetime
SEP, which to some extent can be investigated
retrospectively, associations for growth, cogni-
tion, and mental health can be assessed only
with prospectively obtained measures at differ-
ent life stages.
CONCEPTUAL FRAMEWORKS
100. Conceptual frameworks have been developed
to guide research on the life course processes
leading to adult disease. Investigators have pro-
posed various general models that have then
been adapted and applied to different health
outcomes. Although such frameworks have
been used in other contexts (e.g., record link-
age studies), they are particularly relevant in the
investigation of birth cohorts.
Figure 1 provides an example of a general
framework, with main components that are
often considered in life course research. This
simplified representation incorporates inter-
generational factors, developmental domains
(cognitive, emotional, and physical), social
identities and health behaviors, and environ-
mental influences that potentially act at all life
stages to affect later health. Figure 1 is pre-
sented to highlight five main points. First, birth
cohort studies, in general, can focus on deter-
minants of the full spectrum of both health and
disease in a population. Second, life course tra-
jectories for body functions (e.g., muscle func-
tion, lung function) are a dynamic way to study
lifetime influences on health and disease; these
trajectories capture the natural history of bio-
logical systems that grow and develop rapidly
LIFE COURSE MODELS OF ADULT DISEASE
OUTCOMES
The critical period model (also called biological programming
or
latency model) refers to exposures acting during a critical
window
101. of development that affect the structure or function of organs,
tissues, or body systems and which, in turn, affect later disease
risk. This model underpins the fetal origins of adult disease hy-
pothesis. Sensitive-period models are similar, with exposures
ex-
erting greatest effects during times of rapid development, but
there is greater scope for modification by other influences than
there is with a critical period model.
The accumulation of risk model refers to the adverse effect
on later disease of exposures accumulating over the life course.
It thereby focuses on total burden of insults, i.e., the number,
duration, or severity of a range of health-damaging environmen-
tal, socioeconomic, and behavioral factors.
The chains of risk model (also pathways model) refers to se-
quences of events or exposures, whereby one exposure increases
the likelihood that another will follow, leading to a final expo-
sure(s) that is causally related to later disease. Links are not de-
terministic, and earlier exposures do not affect disease risk but
often lead to a final link in the chain that does affect later
disease
risk. Social, biological, and psychological factors can be part of
chains of risk models, possibly acting as mediating or
modifying
factors.
Sources: adapted from Hertzman et al. (38), Keating &
Hertzman (50), Ben-Shlomo & Kuh (4), and Kuh et al. (52)
during the prenatal, prepubertal, and pubertal
periods, reaching a peak or plateau at maturity
and gradually declining with age (Figure 2).
The progressive, generalized deterioration in
function postmaturity can be thought of as bi-
ologically aging; the generally accepted dispos-
102. able soma theory of aging suggests this is caused
by increasing molecular and cellular damage
from environmental insults and chance (51).
Third, influences over the life course might
operate in several ways to affect adult function
and disease. Researchers have identified models
for the alternative processes that might be in-
volved; main models including critical period,
accumulation, or chains of risk are shown in the
sidebar, Life Course Models of Adult Disease
Outcomes. Although these life course models
www.annualreviews.org • Life Course Research on Adult
Disease 11
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20
107. Parents/
grandparents
Social (origins) identity/
health behavior
Social (destinations)
identity/health behavior
Health declineHealth gain
Figure 1
Simplified framework linking early-life exposures with adult
outcome.
can be seen as distinct, they are not necessarily
mutually exclusive, and one can envisage varia-
tions of basic models. For example, an exposure
that operates during a critical or sensitive pe-
riod may also accumulate with other exposures
over the life course, possibly through modifica-
tion of earlier factors by those occurring later
in life. Fourth, developmental domains may
Years of life
L
e
v
e
l
o
108. f
fu
n
c
ti
o
n
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
Level below which
limitations may occur
Adult risk factors
Ea
rl
y
lif
e
109. ri
sk
fa
ct
o
rs
A
B
C
D
Functional/structural
reserve
Figure 2
Life course functional trajectories. Line A, normal development
and decline;
line B, exposure during development reducing functional
reserve at maturity;
line C, exposure acting postmaturity, accelerating age-related
decline; line D,
combination of B and C. Figure modified from A Life-Course
Approach to Chronic
Disease Epidemiology, edited by Diana Kuh and Yoav Ben-
Shlomo, 2nd edition,
2004, chapter 1, page 9, figure 1.2, by permission of Oxford
University Press.
coevolve, e.g., between physical developmental