This document discusses longitudinal waves, in which particle motion is parallel to the direction of wave propagation. Longitudinal waves include sound waves, which can propagate through gases, liquids, and solids. The document describes how a periodic longitudinal wave can be produced by a piston moving with simple harmonic motion, causing variations in pressure and density. It defines key characteristics of longitudinal waves like displacement, pressure variation, wavelength, frequency, speed and relates these to properties of the medium like bulk modulus and density. The speed of sound, power, intensity, and the inverse square law for intensity from a point source are also covered.
Explains the structure of the atom and its discovery
**More good stuff available at:
www.wsautter.com
and
http://www.youtube.com/results?search_query=wnsautter&aq=f
Explains the structure of the atom and its discovery
**More good stuff available at:
www.wsautter.com
and
http://www.youtube.com/results?search_query=wnsautter&aq=f
My Learning object describes what standing waves are, how to determine where the nodes and antinodes of a standing wave are and also about the fundamental and resonant frequencies. Their is a variety of questions from multiple choice, to true and false and also a problem solving question.
In this presentation, I explain what a standing wave on a string is, the difference between a standing wave and a travelling wave, and go over some practice problems.
Vibration? Do you know what is vibration and how it is important and unimportant for us. What are the different types of vibration,where vibration effects are desirable and where not. What are the useful effects of the vibration and how it can make useful. How vibration can be eliminated or reduced to some extent. Different terminology or fundamentals of vibration is discussed briefly. So find the easy and simple description about vibration.
My Learning object describes what standing waves are, how to determine where the nodes and antinodes of a standing wave are and also about the fundamental and resonant frequencies. Their is a variety of questions from multiple choice, to true and false and also a problem solving question.
In this presentation, I explain what a standing wave on a string is, the difference between a standing wave and a travelling wave, and go over some practice problems.
Vibration? Do you know what is vibration and how it is important and unimportant for us. What are the different types of vibration,where vibration effects are desirable and where not. What are the useful effects of the vibration and how it can make useful. How vibration can be eliminated or reduced to some extent. Different terminology or fundamentals of vibration is discussed briefly. So find the easy and simple description about vibration.
CBSE Physics/ Lakshmikanta Satapathy/ Wave theory/ path difference and Phase difference/ Speed of sound in a gas/ Intensity of wave/ Superposition of waves/ Interference of waves
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...
Topic 5 longitudinal wave
1. Topic 2-3 Longitudinal Waves
1
UEEP1033 Oscillations and Waves
Topic 5
Longitudinal Waves
waves in which the particle or oscillator motion is in
the same direction as the wave propagation
Longitudinal waves propagate as sound waves in all
phases of matter, plasmas, gases, liquids and solids
2. Topic 2-3 Longitudinal Waves
2
UEEP1033 Oscillations and Waves
• Motion of one-dimensional
longitudinal pulse moving
through a long tube containing a
compressible gas
• When the piston is suddenly
moved to the right, the gas just in
front of it is compressed
– Darker region in b
– The pressure and density in
this region are higher than
before the piston was pushed
Pressure Variation in Sound Waves
3. Topic 2-3 Longitudinal Waves
3
UEEP1033 Oscillations and Waves
• When the piston comes to
rest, the compression region
of the gas continues to move
– This corresponds to a
longitudinal pulse
traveling through the
tube with speed v
Pressure Variation in Sound Waves
4. Topic 2-3 Longitudinal Waves
4
UEEP1033 Oscillations and Waves
Producing a Periodic Sound Wave
• A one-dimensional periodic sound
wave can be produced by causing
the piston to move in simple
harmonic motion
• The darker parts of the areas in the
figures represent areas where the
gas is compressed and the density
and pressure are above their
equilibrium values
• The compressed region is called a
compression
5. Topic 2-3 Longitudinal Waves
5
UEEP1033 Oscillations and Waves
• When the piston is pulled back, the gas in front of it expands
and the pressure and density in this region ball below their
equilibrium values
• The low-pressure regions are called rarefactions
• They also propagate along the tube, following the
compressions
• Both regions move at the speed of sound in the medium
• The distance between two successive compressions (or
rarefactions) is the wavelength
Producing a Periodic Sound Wave
6. Topic 2-3 Longitudinal Waves
6
UEEP1033 Oscillations and Waves
Periodic Sound Waves, Displacement
• As the regions travel through the tube, any small element of the
medium moves with simple harmonic motion parallel to the
direction of the wave
• The harmonic position function:
smax = maximum position of the element relative to
equilibrium (or displacement amplitude of the wave)
k = wave number
ω = angular frequency of the wave
* Note the displacement of the element is along x, in the
direction of the sound wave
)cos(),( max tkxstxs ω−=
7. Topic 2-3 Longitudinal Waves
7
UEEP1033 Oscillations and Waves
Periodic Sound Waves, Pressure
• The variation in gas pressure, , is also periodic
= pressure amplitude (i.e. the maximum change in
pressure from the equilibrium value)
• The pressure can be related to the displacement:
B is the bulk modulus of the material
)sin(max tkxPP ω−∆=∆
maxP∆
maxmax BksP =∆
P∆
8. Topic 2-3 Longitudinal Waves
8
UEEP1033 Oscillations and Waves
Periodic Sound Waves
• A sound wave may be considered
either a displacement wave or a
pressure wave
• The pressure wave is 90o
out of
phase with the displacement wave
• The pressure is a maximum when
the displacement is zero, etc
9. Topic 2-3 Longitudinal Waves
9
UEEP1033 Oscillations and Waves
Speed of Sound in a Gas
• Consider an element of the gas between the piston and the dashed line
• Initially, this element is in equilibrium under the influence of forces of
equal magnitude
– force from the piston on left
– another force from the rest of the gas
– These forces have equal magnitudes of PA
• P is the pressure of the gas
• A is the cross-sectional area of the tube
element of the gas
10. Topic 2-3 Longitudinal Waves
10
UEEP1033 Oscillations and Waves
Speed of Sound in a Gas
• After a time period, Δt, the piston has moved to the right at a
constant speed vx.
• The force has increased from PA to (P+ΔP)A
• The gas to the right of the element is undisturbed since the sound
wave has not reached it yet
11. Topic 2-3 Longitudinal Waves
11
UEEP1033 Oscillations and Waves
Impulse and Momentum
• The element of gas is modeled as a non-isolated system in
terms of momentum
• The force from the piston has provided an impulse to the
element, which produces a change in momentum
• The impulse is provided by the constant force due to the
increased pressure:
• The change in pressure can be related to the volume change
and the bulk modulus:
( )itPAtFI ˆ∆∆=∆= ∑
v
v
B
V
V
BP x
=
∆
−=∆
it
v
v
ABI x ˆ
∆=⇒
12. Topic 2-3 Longitudinal Waves
12
UEEP1033 Oscillations and Waves
Impulse and Momentum
• The change in momentum of the element of gas of mass m is
( )itAvvvmp x
ˆ∆ρ=∆=∆
( )itAvvit
v
v
AB
pI
x
x ˆˆ ∆ρ=
∆
∆=
• The force from the piston has provided an impulse to the element,
which produces a change in momentum
B = bulk modulus of the material
ρ = density of the material
ρ=⇒ /Bv
13. Topic 2-3 Longitudinal Waves
13
UEEP1033 Oscillations and Waves
Speed of Sound Waves, General
• The speed of sound waves in a medium depends on the
compressibility and the density of the medium
• The compressibility can sometimes be expressed in terms of
the elastic modulus of the material
• The speed of all mechanical waves follows a general form:
• For a solid rod, the speed of sound depends on Young’s
modulus and the density of the material
propertyinertial
propertyelastic
=v
14. Topic 2-3 Longitudinal Waves
14
UEEP1033 Oscillations and Waves
Speed of Sound in Air
• The speed of sound also depends on the temperature of the
medium
– This is particularly important with gases
• For air, the relationship between the speed and temperature is
331.3 m/s = the speed at 0o
C
TC = air temperature in Celsius
15.273
1)m/s3.331( cT
v +=
15. Topic 2-3 Longitudinal Waves
15
UEEP1033 Oscillations and Waves
Relationship Between Pressure and Displacement
• The pressure amplitude and the displacement amplitude are
related by:
ΔPmax = B k smax
• The bulk modulus is generally not as readily available as the
density of the gas
• By using the equation for the speed of sound, the relationship
between the pressure amplitude and the displacement
amplitude for a sound wave can be found:
ΔPmax = ρ v ω smax
ρ= /Bv
vk /ω=
16. Topic 2-3 Longitudinal Waves
16
UEEP1033 Oscillations and Waves
Speed of Sound in Gases, Example Values
17. Topic 2-3 Longitudinal Waves
17
UEEP1033 Oscillations and Waves
Energy of Periodic Sound Waves
• Consider an element of air with
mass Δm and length Δx
• Model the element as a particle
on which the piston is doing
work
• The piston transmits energy to
the element of air in the tube
• This energy is propagated away
from the piston by the sound
wave
18. Topic 2-3 Longitudinal Waves
18
UEEP1033 Oscillations and Waves
Power of a Periodic Sound Wave
• The rate of energy transfer is the power of the wave
• The average power is over one period of the oscillation
xvF
⋅=Power
( ) 2
max
2
avg
2
1
Power sAvωρ=
19. Topic 2-3 Longitudinal Waves
19
UEEP1033 Oscillations and Waves
)(sin
)]sin()][sin([
)]cos([)]sin([
ˆ)],([ˆ]),([Power
22
max
2
maxmax
maxmax
tkxAsv
tkxstkxAsv
tkxs
t
tkxAsv
itxs
t
iAtxP
ω−ωρ=
ω−ωω−ωρ=
ω−
∂
∂
ω−ωρ=
∂
∂
⋅∆=
• Find the time average power is over one period of the oscillation
2
1
2
2sin
2
1
sin
1
)0(sin
1
0
0
2
0
2
=
ω
ω
+=ω=ω− ∫∫
T
TT tt
T
dtt
T
dtt
T
• For any given value of x, which we choose to be x = 0, the average
value of over one period T is:)(sin2
tkx ω−
20. Topic 2-3 Longitudinal Waves
20
UEEP1033 Oscillations and Waves
Intensity of a Periodic Sound Wave
• Intensity of a wave I = power per unit area
= the rate at which the energy being transported by the wave
transfers through a unit area, A, perpendicular to the
direction of the wave
• Example: wave in air
( )
A
I
avgPower
=
2
max
2
2
1
svI ωρ=
21. Topic 2-3 Longitudinal Waves
21
UEEP1033 Oscillations and Waves
Intensity
• In terms of the pressure amplitude,
( )
v
P
I
ρ
∆
=
2
2
max
• Therefore, the intensity of a periodic sound wave is
proportional to the
• square of the displacement amplitude
• square of the angular frequency
2
maxs
2
ω
22. Topic 2-3 Longitudinal Waves
22
UEEP1033 Oscillations and Waves
A Point Source
• A point source will emit sound waves
equally in all directions - this can result in a
spherical wave
• This can be represented as a series of
circular arcs concentric with the source
• Each surface of constant phase is a wave
front
• The radial distance between adjacent wave
fronts that have the same phase is the
wavelength λ of the wave
• Radial lines pointing outward from the
source, representing the direction of
propagation, are called rays
23. Topic 2-3 Longitudinal Waves
23
UEEP1033 Oscillations and Waves
Intensity of a Point Source
• The power will be distributed equally through the area of the
sphere
• The wave intensity at a distance r from the source is:
• This is an inverse-square law
The intensity decreases in proportion to the square of the
distance from the source
( ) ( )
2
avgavg
4
PowerPower
rA
I
π
==