This document provides instructions for a laboratory exercise on media preparation and evaluation. It discusses obtaining bacterial isolates, using different types of media such as defined, complex, enriched, and selective media to culture microbes. It describes evaluating colony morphology and interpreting microbial growth on various media. Specific media such as MacConkey agar, EMB agar, and mannitol salt agar are discussed. Procedures for preparing and pouring agar plates are also outlined. Common bacteria used in the exercise are listed. References for further information are provided.
A discussion on the media and biochemical tests as discussed by Ms. Caryl Villalon, RN, MT. Covers the descriptions of the media and biochemical tests. How to perform the tests, properties of the tests, media and reagents used, and the results of the test. Pictures of positive and negative results are also shown in the slide.
A discussion on the media and biochemical tests as discussed by Ms. Caryl Villalon, RN, MT. Covers the descriptions of the media and biochemical tests. How to perform the tests, properties of the tests, media and reagents used, and the results of the test. Pictures of positive and negative results are also shown in the slide.
Biochemical tests for bacterial identificationSuprakash Das
Basic biochemical tests for identification of most common bacteria along with their principles and methods to perform and quality control for UG & PG Students.
INDOLE TEST
UREASE TEST
CITRATE TEST
METHYL RED(MR) TEST
VOGES – PROSKAUER(VP) TEST
TRIPLE SUGAR IRON(TSI) TEST
OXIDASE TEST
CATALASE TEST
CATALASE TEST-Principle:-
This test demonstrates presence of catalase enzyme. This enzyme catalyses the release of O2 from H2O2.
catalase
2H2O2 H2O + increase O2
Reagents:- 1) 3% H2O2.
2) 24 hrs cultured organisms
Procedure:-
With sterile wooden stick transfer culture organisms to test tube containing 3% H2O2 and observe for production of effervescence.
It can also be tested directly on growth plate.
Positive Control: Staphylococci.
Negative Control: Streptococci.
False positive reactions:
If culture medium contains catalase enzyme e.g., blood agar, chocolate agar.
If iron wire loop is used
The enterobacteriaceae basic properties.ppsx xNursing Path
The Enterobacteriaceae are a large family of Gram-negative bacteria that includes, along with many harmless symbionts, many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella, and Shigella.
Culture media in microbiology refers to the solid or liquid substances used to cultivate and grow microorganisms such as bacteria, fungi, and viruses in a laboratory setting. These media provide the necessary nutrients, environment, and conditions for microorganisms to thrive and reproduce. The choice of culture media depends on the specific requirements of the microorganisms being studied, as different organisms have varied nutritional needs and environmental preferences.
Biochemical tests for bacterial identificationSuprakash Das
Basic biochemical tests for identification of most common bacteria along with their principles and methods to perform and quality control for UG & PG Students.
INDOLE TEST
UREASE TEST
CITRATE TEST
METHYL RED(MR) TEST
VOGES – PROSKAUER(VP) TEST
TRIPLE SUGAR IRON(TSI) TEST
OXIDASE TEST
CATALASE TEST
CATALASE TEST-Principle:-
This test demonstrates presence of catalase enzyme. This enzyme catalyses the release of O2 from H2O2.
catalase
2H2O2 H2O + increase O2
Reagents:- 1) 3% H2O2.
2) 24 hrs cultured organisms
Procedure:-
With sterile wooden stick transfer culture organisms to test tube containing 3% H2O2 and observe for production of effervescence.
It can also be tested directly on growth plate.
Positive Control: Staphylococci.
Negative Control: Streptococci.
False positive reactions:
If culture medium contains catalase enzyme e.g., blood agar, chocolate agar.
If iron wire loop is used
The enterobacteriaceae basic properties.ppsx xNursing Path
The Enterobacteriaceae are a large family of Gram-negative bacteria that includes, along with many harmless symbionts, many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella, and Shigella.
Culture media in microbiology refers to the solid or liquid substances used to cultivate and grow microorganisms such as bacteria, fungi, and viruses in a laboratory setting. These media provide the necessary nutrients, environment, and conditions for microorganisms to thrive and reproduce. The choice of culture media depends on the specific requirements of the microorganisms being studied, as different organisms have varied nutritional needs and environmental preferences.
he culture media are classified in many different ways: Based on the physical state Liquid media Solid media Semisolid media Based on the presence or absence of oxygen Anaerobic media Aerobic media Based on nutritional factors Simple media Synthetic media Complex
culture media
CULTURE – Is term given to microorganisms that are cultivated in the lab for the purpose of studying them.
MEDIUM – Is the term given to the combination of ingredients that will support the growth & cultivation of microorganisms outside their natural habitats.
Necessary Requirements for Growth of Bacteria
Distilled Water
Nitrogen containing compounds
Peptone- Golden granular powder
Complex mixture of partially digested protiens by proteolytic
enzymes pepsin, trysin or papain
Peptones, Proteoses, polypeptides, aminoacids, inorganic salts like phosphates
potassium & magnesium
Accessory growth factors like nicotinic acid & riboflavin
Energy sources
Suitable Ph- 7.2 – 7.4
Solidifying agents:
Gelatin– Protien
Agar— Chief component is Long chain Polysaccharide
Melts at 95°c & solidify only when cooled to about 42°c
1- 2% yields a suitable gel eg. Non-nutritive agar
According to Physical State:
Liquid – Peptone Water, Nutrient Broth
Semisolid – Nutrient Agar Stabs
Solid – Blood Agar
According to Oxygen requirement:
Aerobic Medium
Anaerobic Media
Announcement about my previous presentations - Thank youAreej Abu Hanieh
ANNOUNCEMENT Thank you for all of you, my followers who sent me messages with a lot of love and appreciations, I finally graduated after 6 years of studying in Birzeit University , In doctor of Pharmacy department I hope all of you benefited from all the presentations posted before Thank you a new PharmD GraduatedAreej ^^
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
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.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
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.
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.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
2. Obtain definitive identification and characterization
Determine which bacteria is likely a contaminant or
colonizer
Storage of pure cultures
3.
4. Use, defined ,complex, enriched selective &
differential media to culture microbes.
Learn how to prepare media for bacterial cultivation
Describe colony morphology and its relationship to
microbial identification.
Interpret results of microbial growth on various
culture media.
5. A. On Consistency There are three physical forms of
media Solid, Semisolid , and Liquid
6. B. On Chemical Composition
- Defined , undefined or complex
- Simple media, special media(enriched, selective, and
deferential )
-Aerobic and anaerobic media
- Cell culture for obligate intracellular
bacteria (e.g., Chlamydia spp)
7. Medium Contents Reaction
MacConkey
agar
lactose,
bile salts, crystal violet,
neutral red
Only one sugar
Inhibit G+ve organisms
Turns red when acid (pH<6.8) is produced
Non-lactose fermenters appear colorless or
transparent
EMB agar Lactose
Sucrose
Eosin
methylene blue
Strong acid production by organisms such as E.
coli results in a metallic green sheen.
Weaker fermentation of lactose results in
colonies with a pinkish-purple color
nonlactose fermenters remain colorless.
pH indicator
Inhibit G+ve organisms
MSA
Manitol salt
agar
High salts 7.5% NaCl
Mannitol
pH indicator phenol red
Inhibit most G-ve bacteria and many G
+ve
Differentiate between salt tolerant
bacteria by mannitol fermentation
8. Galactoside bond
Glucose + Galactose
Two enzymes are required:
1. beta-galactoside permease to transport the disaccharide
through the CW
2. Beta galactosidase which hydrolyze the galactoside bond
Question: Why glucose is not included in selective media?
.
2 enzymes needed
Fermented by the EMP pathway
10. Streptococci are typically grouped by hemolysis on blood
agar plates:
Alpha hemolysis:
› occurs when the RBCs are intact, but hemoglobin is
converted to methemoglobin . This causes a greening of
the plate.
Beta hemolysis:
› True hemolysis due to hemolysin, an erythrocyte lysing
enzyme.
› The plate becomes clear where the blood cells have been
lysed.
Gamma hemolysis , there is actually no hemolysis.
13. 1. Read the label on a bottle of dehydrated agar. It specifies the amount of
dehydrated powder required to make 1 liter (1,000 ml) of medium. Calculate the
amount needed for 0.2 liter and weigh out this quantity
2. Place 200 ml of distilled water in an Erlenmeyer flask. Add the weighed,
dehydrated agar while stirring with a glass rod to prevent lumping.
3. Set the flask on a tripod. Using a Bunsen flame, slowly bring the rehydrated
agar to a boil. Stir often.
4. When the agar mixture is completely dissolved, remove the flask from the
flame ,close it with the aluminum foil plug or cap, and give it to the instructor to
be sterilized in the autoclave
5. When the flask of sterilized agar is returned to you, allow it to cool to about
50°C . pour the melted, sterile agar into a series of petri dishes. The petri dish tops
are lifted with the left hand, and the bottoms are filled to about one-third capacity
with melted agar
When the plates are cool (agar solidified), invert them to prevent condensing
moisture from accumulating on the agar surfaces.
14. Escherichia coli
Staphylococcus aureus
Proteus mirabilis
Staphylococcus aureus
Escherichia coli
Staphylococcus
epidermidis
Staphylococcus aureus , Bacillus
subtilis and Enterococcus faecalis
What to Do