ELISA and its advantages
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The document summarizes the development and basic principles of enzyme-linked immunosorbent assays (ELISAs). It explains that ELISAs were developed as an alternative to radioimmunoassays, which used radioactive labels. ELISAs link antibodies to enzymes, which catalyze color changes in substrates to signal the presence of antigens. The ELISA procedure results in a colored end product corresponding to antigen levels. ELISAs can provide quantitative, qualitative, or semi-quantitative results by comparing sample readings to a standard curve of known antigen concentrations. Common applications of ELISAs include screening blood donations and measuring hormone levels.
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Enzyme Linked Immunosorbent Assay (ELISA) is a very sensitive immunochemical technique which is used to access the presence of specific protein (antigen or antibody) in the given sample and it’s quantification.
It is also called solid-phase enzyme immunoassay as it employs an enzyme linked antigen or antibody as a marker for the detection of specific protein.
ELISA has been used as a diagnostic tool in medicine, plant pathology and in the food industry as a quality control check.
Elisa Development Guide
ELISA Development Guide from Creative Diagnostics. Creative Diagnostics provides contract ELISA kit development services for the R&D and IVD community.
Complement fixation
The complement fixation test detects antibodies in patient serum. It requires several components mixed at optimal concentrations, including sheep red blood cells bound to anti-sheep immunoglobulin G. The test consists of an indicator system using these red blood cells and an exogenous complement source. When the patient's serum contains a complement-fixing antibody, it will bind antigens and fix the complement, preventing lysis of the indicator red blood cells and yielding a positive result. While more demanding than other detection methods, complement fixation was commonly used but has been replaced by more sensitive techniques.
Elisa
ELISA, or enzyme-linked immunosorbent assay, is an immunoassay technique used to detect antibodies, antigens, or other proteins. It works by binding an antigen or antibody to a well, adding an enzyme-linked antibody or antigen, and detecting the reaction using a chromogenic substrate. There are three main types: direct ELISA detects antigens, indirect ELISA detects antibodies, and competitive ELISA detects antigens by competition for antibody binding sites. The intensity of color developed is proportional to the concentration of the target being detected.
Agglutination
Agglutination is the clumping or clustering of antigens by antibodies. It occurs when antibodies bind to particulate antigens in equivalent proportions, causing the antigens to crosslink and aggregate. Better agglutination is seen with IgM antibodies than IgG antibodies. Agglutination involves antigen-antibody binding at the zone of equivalence according to the lock-and-key principle. This binding leads to the formation of a visible lattice structure as antibodies crosslink multiple antigen molecules.
ELISA
Immunological, plate-based assay used for quantifying and detecting soluble substances in biological samples.
ELISA – Enzyme Linked Immuno Sorbent Assay
An Enzyme-Linked Immunosorbent Assay, also called ELISA or EIA.
This is quantitative immunological assay / test commonly used to detects/measure antibodies, antigens & proteins in biological samples. ( Blood, Urine, CSF etc.)
Use an enzyme to detect the binding of antigen (Ag) antibody (Ab).
The most commonly used conjugate enzyme labels are Horseradish Peroxidase (HRP) and Alkaline phosphatase (AP).
Other enzymes have been used as well; these include β-galactosidase, catalase and acetylcholinesterase.
Invaders Of The Body
Antigens are molecules that trigger an acquired immune response. They include proteins, lipids, carbohydrates, and nucleic acids from pathogens like bacteria and viruses. A good antigen is chemically stable, complex, particulate, foreign, and elicits a strong immune response depending on factors like dose, route of administration, and host genetics. Antigens are recognized by antibodies through epitopes, the specific sites on antigens that antibodies bind to. Haptens are small molecules that are not immunogenic alone but can elicit an immune response when attached to a carrier protein.
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ELISA TEST
Enzyme Linked Immunosorbent Assay (ELISA) is a very sensitive immunochemical technique which is used to access the presence of specific protein (antigen or antibody) in the given sample and it’s quantification.
It is also called solid-phase enzyme immunoassay as it employs an enzyme linked antigen or antibody as a marker for the detection of specific protein.
ELISA has been used as a diagnostic tool in medicine, plant pathology and in the food industry as a quality control check.
Elisa Development Guide
ELISA Development Guide from Creative Diagnostics. Creative Diagnostics provides contract ELISA kit development services for the R&D and IVD community.
Complement fixation
The complement fixation test detects antibodies in patient serum. It requires several components mixed at optimal concentrations, including sheep red blood cells bound to anti-sheep immunoglobulin G. The test consists of an indicator system using these red blood cells and an exogenous complement source. When the patient's serum contains a complement-fixing antibody, it will bind antigens and fix the complement, preventing lysis of the indicator red blood cells and yielding a positive result. While more demanding than other detection methods, complement fixation was commonly used but has been replaced by more sensitive techniques.
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ELISA, or enzyme-linked immunosorbent assay, is an immunoassay technique used to detect antibodies, antigens, or other proteins. It works by binding an antigen or antibody to a well, adding an enzyme-linked antibody or antigen, and detecting the reaction using a chromogenic substrate. There are three main types: direct ELISA detects antigens, indirect ELISA detects antibodies, and competitive ELISA detects antigens by competition for antibody binding sites. The intensity of color developed is proportional to the concentration of the target being detected.
Agglutination
Agglutination is the clumping or clustering of antigens by antibodies. It occurs when antibodies bind to particulate antigens in equivalent proportions, causing the antigens to crosslink and aggregate. Better agglutination is seen with IgM antibodies than IgG antibodies. Agglutination involves antigen-antibody binding at the zone of equivalence according to the lock-and-key principle. This binding leads to the formation of a visible lattice structure as antibodies crosslink multiple antigen molecules.
ELISA
Immunological, plate-based assay used for quantifying and detecting soluble substances in biological samples.
ELISA – Enzyme Linked Immuno Sorbent Assay
An Enzyme-Linked Immunosorbent Assay, also called ELISA or EIA.
This is quantitative immunological assay / test commonly used to detects/measure antibodies, antigens & proteins in biological samples. ( Blood, Urine, CSF etc.)
Use an enzyme to detect the binding of antigen (Ag) antibody (Ab).
The most commonly used conjugate enzyme labels are Horseradish Peroxidase (HRP) and Alkaline phosphatase (AP).
Other enzymes have been used as well; these include β-galactosidase, catalase and acetylcholinesterase.
Invaders Of The Body
Antigens are molecules that trigger an acquired immune response. They include proteins, lipids, carbohydrates, and nucleic acids from pathogens like bacteria and viruses. A good antigen is chemically stable, complex, particulate, foreign, and elicits a strong immune response depending on factors like dose, route of administration, and host genetics. Antigens are recognized by antibodies through epitopes, the specific sites on antigens that antibodies bind to. Haptens are small molecules that are not immunogenic alone but can elicit an immune response when attached to a carrier protein.
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The document discusses various types of antigen-antibody reactions:
1) Precipitation reactions occur when antigen is mixed with antibodies.
2) Agglutination reactions cause particulate antigens to clump together when mixed with antibodies in the presence of electrolytes. Common examples are blood grouping and detection of typhoid.
3) Neutralization reactions involve antitoxins neutralizing toxins. Examples include toxigenicity tests and the Schick test.
Antigen antibody interaction .pptx 1
This document summarizes antigen-antibody interactions. It describes how antibodies specifically bind to antigens via epitopes and paratopes. The binding is due to non-covalent interactions like hydrogen bonds and van der Waals forces. This interaction forms the basis of serological tests like precipitation, agglutination, complement fixation and ELISA, which are used to detect infectious diseases. The document also discusses properties of antigen-antibody reactions like affinity, avidity and specificity.
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This document provides an overview of ELISA (Enzyme-Linked Immunosorbent Assay). It describes ELISA as a method for detecting antibodies or antigens using enzyme-linked antibodies and a chromogenic substrate. The document outlines the basic ELISA procedure and discusses different ELISA types including direct, indirect, sandwich, and competitive ELISA. It also notes applications of ELISA for detecting antigens and antibodies and compares ELISA to other detection methods.
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This document outlines the key concepts to be covered in a lecture on antigen-antibody reactions, including:
1. The variable region of immunoglobulins and its interaction with antigenic determinants.
2. The difference between antibody affinity relating to a single Fab region and avidity relating to the total strength of binding of multiple Fab regions.
3. Techniques to be discussed include precipitin curves, immunodiffusion, immunofluorescence, ELISA, and definitions of agglutination and differences between IgM and IgG antibodies.
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these slides will let you know about the ELISA and its types and how it is preformed in the laboratory
Agglutination
1) Agglutination tests detect antigens or antibodies by exploiting the ability of antibodies to cross-link antigen-coated particles, forming visible clumps or lattices.
2) There are several types of agglutination tests including direct, passive, and reverse passive agglutination as well as hemagglutination and hemagglutination inhibition.
3) Agglutination tests are useful, rapid techniques for detecting various infectious diseases and other analytes but can be limited by prozone effects at high antibody concentrations.
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What is ELISA.
Principle.
History.
Types of ELISA method.
1.Direct ELISA.
2.Indirect ELISA.
3.Sandwhich ELISA.
Conclusion.
References.
Antibodies (also known as immunoglobulins abbreviated Ig) are gamma globulin proteins that are found in blood and are used by the immune system to identify and neutralize foreign objects, such as bacteria and viruses.
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Immunologic methods are used in the laboratory diagnosis of infections by detecting the interaction between antigens and antibodies. Common techniques include agglutination, immunofluorescence, ELISA, and immunoblotting. Agglutination involves clumping of antigens by antibodies that can be seen visually. Immunofluorescence uses antibodies coupled to fluorescent dyes to identify antigens under UV light. ELISA detects antigens or antibodies through an enzymatic reaction, while immunoblotting confirms antibody presence by blotting proteins and detecting binding. These methods exploit the high specificity of the antigen-antibody reaction for diagnostic purposes.
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This document discusses antigen-antibody reactions. It begins by defining antigen-antibody reactions as the specific interaction between antigens and antibodies. It then describes the three stages of antigen-antibody reactions: initial formation of antigen-antibody complexes, followed by visible events like precipitation or agglutination, and finally neutralization or destruction of antigens. The document also discusses various types of antigen-antibody reactions like precipitation, agglutination, and immunoassays. It provides examples of applications of antigen-antibody reactions like disease detection, identification of bacteria, and standardization of toxins.
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Reverse passive agglutination test coats antibodies onto carrier molecules that detect antigens in a patient's serum. For example, this test can be used to detect cholera toxin by coating cholera toxin antibodies onto carrier molecules which will agglutinate or clump if the cholera toxin antigen is present in a serum sample. This provides a detection method for certain antigens by reversing the roles of the antibody and antigen compared to a standard agglutination test.
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Dr. ihsan edan abdulkareem alsaimary
PROFESSOR IN MEDICAL MICROBIOLOGY AND MOLECULAR IMMUNOLOGY
ihsanalsaimary@gmail.com
mobile : 009647801410838
university of basrah - college of medicine - basrah -IRAQ
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If you are interested in one then please see our site
www.lablinkpk.com
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lablinks@lablinkspk.com
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The document discusses various principles and applications of antigen-antibody interactions, including:
1. Antigen-antibody interactions involve noncovalent bonds between antigens and antibodies, similar to enzyme-substrate interactions.
2. There are four main types of forces involved in antigen-antibody binding - affinity, avidity, specificity, and cross-reactivity.
3. Various techniques are used to detect and measure antigen-antibody interactions, including precipitation reactions, agglutination tests, radioimmunoassay, enzyme-linked immunosorbent assay, and Western blotting.
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This document summarizes various antigen-antibody interaction techniques including: precipitation reactions, agglutination reactions, radioimmunoassay, enzyme-linked immunosorbent assay, Western blotting, immunoprecipitation, immunofluorescence, flow cytometry, and alternatives like protein A/G and biotin-avidin interactions. It describes how each technique detects and analyzes the binding between antigens and antibodies through measurements, visualizations, or separations based on properties like molecular weight, charge, or fluorescent labeling.
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The complement fixation test (CFT) involves mixing antigen, antibody, and complement. If the antibody is specific to the antigen, it will bind and "fix" the complement, preventing it from lysing red blood cells. In a positive test, lysis does not occur, while a negative test results in lysis. CFT is used to detect antibodies against pathogens like syphilis, and can detect antibody levels below 1 microgram/ml. It has limitations like being time-consuming and labor-intensive. Variations involve using different complement sources or detection methods depending on the pathogen.
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This document discusses immunity and antigen-antibody reactions. It begins with definitions of immunity, antigens, and antibodies. It describes the components of the immune system including antigen specificity and types of antigens. It then explains antigen-antibody reactions and how they are used for diagnostic tests. Different diagnostic tests are also summarized, including precipitation reactions, agglutination, immunofluorescence, radioimmunoassay, and ELISA. Potential sources of markers for periodontal disease activity are also listed.
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ELISA (enzyme-linked immunosorbent assay) is a biochemical technique used to detect the presence of antibodies and antigens in a liquid sample. It relies on an enzyme-linked antibody or antigen to detect the target protein. There are different types of ELISA including direct, indirect, sandwich, and competitive. The ELISA process involves coating a plate with an antigen or antibody, adding a sample and enzyme-linked antibody, washing unbound material, and detecting the enzyme's product to quantify the target. ELISAs are widely used in medical testing, food safety, and disease detection.
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The document discusses various types of antigen-antibody reactions:
1) Precipitation reactions occur when antigen is mixed with antibodies.
2) Agglutination reactions cause particulate antigens to clump together when mixed with antibodies in the presence of electrolytes. Common examples are blood grouping and detection of typhoid.
3) Neutralization reactions involve antitoxins neutralizing toxins. Examples include toxigenicity tests and the Schick test.
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This document summarizes antigen-antibody interactions. It describes how antibodies specifically bind to antigens via epitopes and paratopes. The binding is due to non-covalent interactions like hydrogen bonds and van der Waals forces. This interaction forms the basis of serological tests like precipitation, agglutination, complement fixation and ELISA, which are used to detect infectious diseases. The document also discusses properties of antigen-antibody reactions like affinity, avidity and specificity.
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This document provides an overview of ELISA (Enzyme-Linked Immunosorbent Assay). It describes ELISA as a method for detecting antibodies or antigens using enzyme-linked antibodies and a chromogenic substrate. The document outlines the basic ELISA procedure and discusses different ELISA types including direct, indirect, sandwich, and competitive ELISA. It also notes applications of ELISA for detecting antigens and antibodies and compares ELISA to other detection methods.
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This document outlines the key concepts to be covered in a lecture on antigen-antibody reactions, including:
1. The variable region of immunoglobulins and its interaction with antigenic determinants.
2. The difference between antibody affinity relating to a single Fab region and avidity relating to the total strength of binding of multiple Fab regions.
3. Techniques to be discussed include precipitin curves, immunodiffusion, immunofluorescence, ELISA, and definitions of agglutination and differences between IgM and IgG antibodies.
Elisa and its type
these slides will let you know about the ELISA and its types and how it is preformed in the laboratory
Agglutination
1) Agglutination tests detect antigens or antibodies by exploiting the ability of antibodies to cross-link antigen-coated particles, forming visible clumps or lattices.
2) There are several types of agglutination tests including direct, passive, and reverse passive agglutination as well as hemagglutination and hemagglutination inhibition.
3) Agglutination tests are useful, rapid techniques for detecting various infectious diseases and other analytes but can be limited by prozone effects at high antibody concentrations.
ELISA, principle and method by kk sahu
What is ELISA.
Principle.
History.
Types of ELISA method.
1.Direct ELISA.
2.Indirect ELISA.
3.Sandwhich ELISA.
Conclusion.
References.
Antibodies (also known as immunoglobulins abbreviated Ig) are gamma globulin proteins that are found in blood and are used by the immune system to identify and neutralize foreign objects, such as bacteria and viruses.
Immunology based tests in the laboratory diagnosis of infections
Immunologic methods are used in the laboratory diagnosis of infections by detecting the interaction between antigens and antibodies. Common techniques include agglutination, immunofluorescence, ELISA, and immunoblotting. Agglutination involves clumping of antigens by antibodies that can be seen visually. Immunofluorescence uses antibodies coupled to fluorescent dyes to identify antigens under UV light. ELISA detects antigens or antibodies through an enzymatic reaction, while immunoblotting confirms antibody presence by blotting proteins and detecting binding. These methods exploit the high specificity of the antigen-antibody reaction for diagnostic purposes.
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This document discusses antigen-antibody reactions. It begins by defining antigen-antibody reactions as the specific interaction between antigens and antibodies. It then describes the three stages of antigen-antibody reactions: initial formation of antigen-antibody complexes, followed by visible events like precipitation or agglutination, and finally neutralization or destruction of antigens. The document also discusses various types of antigen-antibody reactions like precipitation, agglutination, and immunoassays. It provides examples of applications of antigen-antibody reactions like disease detection, identification of bacteria, and standardization of toxins.
Immunoelectrophoresis
Immunoelectrophoresis is a technique that combines electrophoresis and immunodiffusion to separate and identify antigen components in a mixture. It involves applying an electric current to separate antigens in agar gel wells, then allowing the antigens to diffuse and react with antibodies placed in troughs cut into the gel. This results in the formation of precipitin lines that indicate reactions between individual antigens and antibodies, allowing different antigens to be identified based on the lines' position and shape. Immunoelectrophoresis is used in medical diagnostics to detect abnormal proteins and monitor antigen purity.
Passive agglutination
Reverse passive agglutination test coats antibodies onto carrier molecules that detect antigens in a patient's serum. For example, this test can be used to detect cholera toxin by coating cholera toxin antibodies onto carrier molecules which will agglutinate or clump if the cholera toxin antigen is present in a serum sample. This provides a detection method for certain antigens by reversing the roles of the antibody and antigen compared to a standard agglutination test.
Immunological diagnostic techniques dr.ihsan alsaimary basrah mediucal college
Dr. ihsan edan abdulkareem alsaimary
PROFESSOR IN MEDICAL MICROBIOLOGY AND MOLECULAR IMMUNOLOGY
ihsanalsaimary@gmail.com
mobile : 009647801410838
university of basrah - college of medicine - basrah -IRAQ
Elisa Basics
If you are interested in one then please see our site
www.lablinkpk.com
Or write to
lablinks@lablinkspk.com
Antigen antibody reactions
1) Affinity refers to the strength of binding between a single antigenic site and antibody binding site, while avidity refers to the overall strength of binding between multivalent antigens and antibodies.
2) Avidity is influenced by both affinity and the valence (number of binding sites) of the antigen and antibody. More binding sites results in higher avidity.
3) Specificity refers to an antibody only binding to one antigen, while cross-reactivity is binding to multiple antigens that share similar epitopes.
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The document discusses various principles and applications of antigen-antibody interactions, including:
1. Antigen-antibody interactions involve noncovalent bonds between antigens and antibodies, similar to enzyme-substrate interactions.
2. There are four main types of forces involved in antigen-antibody binding - affinity, avidity, specificity, and cross-reactivity.
3. Various techniques are used to detect and measure antigen-antibody interactions, including precipitation reactions, agglutination tests, radioimmunoassay, enzyme-linked immunosorbent assay, and Western blotting.
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This document summarizes various antigen-antibody interaction techniques including: precipitation reactions, agglutination reactions, radioimmunoassay, enzyme-linked immunosorbent assay, Western blotting, immunoprecipitation, immunofluorescence, flow cytometry, and alternatives like protein A/G and biotin-avidin interactions. It describes how each technique detects and analyzes the binding between antigens and antibodies through measurements, visualizations, or separations based on properties like molecular weight, charge, or fluorescent labeling.
COMPLEMENT FIXATION TEST - CFT
The complement fixation test (CFT) involves mixing antigen, antibody, and complement. If the antibody is specific to the antigen, it will bind and "fix" the complement, preventing it from lysing red blood cells. In a positive test, lysis does not occur, while a negative test results in lysis. CFT is used to detect antibodies against pathogens like syphilis, and can detect antibody levels below 1 microgram/ml. It has limitations like being time-consuming and labor-intensive. Variations involve using different complement sources or detection methods depending on the pathogen.
Antigen antibody reactions
This document discusses immunity and antigen-antibody reactions. It begins with definitions of immunity, antigens, and antibodies. It describes the components of the immune system including antigen specificity and types of antigens. It then explains antigen-antibody reactions and how they are used for diagnostic tests. Different diagnostic tests are also summarized, including precipitation reactions, agglutination, immunofluorescence, radioimmunoassay, and ELISA. Potential sources of markers for periodontal disease activity are also listed.
Principles and Applications of ELISA
ELISA (enzyme-linked immunosorbent assay) is a biochemical technique used to detect the presence of antibodies and antigens in a liquid sample. It relies on an enzyme-linked antibody or antigen to detect the target protein. There are different types of ELISA including direct, indirect, sandwich, and competitive. The ELISA process involves coating a plate with an antigen or antibody, adding a sample and enzyme-linked antibody, washing unbound material, and detecting the enzyme's product to quantify the target. ELISAs are widely used in medical testing, food safety, and disease detection.
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This document discusses homogeneous and heterogeneous immunoassays. It defines immunoassays as biochemical tests that measure macromolecules or small molecules using antibodies or antigens. Heterogeneous immunoassays involve separating bound and unbound components, while homogeneous immunoassays do not require separation. Examples of immunoassays discussed include ELISA (enzyme-linked immunosorbent assay) and EMIT (enzyme multiplied immunoassay technique).
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ELISA Test – Basic “Need to Know” for Laboratory Professionals
ELISA Test – Basic “Need to Know” for Laboratory Professionals
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The Limited Role of the Streaming Instability during Moon and Exomoon Formation
It is generally accepted that the Moon accreted from the disk formed by an impact between the proto-Earth and
impactor, but its details are highly debated. Some models suggest that a Mars-sized impactor formed a silicate
melt-rich (vapor-poor) disk around Earth, whereas other models suggest that a highly energetic impact produced a
silicate vapor-rich disk. Such a vapor-rich disk, however, may not be suitable for the Moon formation, because
moonlets, building blocks of the Moon, of 100 m–100 km in radius may experience strong gas drag and fall onto
Earth on a short timescale, failing to grow further. This problem may be avoided if large moonlets (?100 km)
form very quickly by streaming instability, which is a process to concentrate particles enough to cause gravitational
collapse and rapid formation of planetesimals or moonlets. Here, we investigate the effect of the streaming
instability in the Moon-forming disk for the first time and find that this instability can quickly form ∼100 km-sized
moonlets. However, these moonlets are not large enough to avoid strong drag, and they still fall onto Earth quickly.
This suggests that the vapor-rich disks may not form the large Moon, and therefore the models that produce vaporpoor disks are supported. This result is applicable to general impact-induced moon-forming disks, supporting the
previous suggestion that small planets (<1.6 R⊕) are good candidates to host large moons because their impactinduced disks would likely be vapor-poor. We find a limited role of streaming instability in satellite formation in an
impact-induced disk, whereas it plays a key role during planet formation.
Unified Astronomy Thesaurus concepts: Earth-moon system (436)
Rodents, Birds and locust_Pests of crops.pdf
Mole rat or Lesser bandicoot rat, Bandicotabengalensis
•Head -round and broad muzzle
•Tail -shorter than head, body
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•Burrows with scooped soil before entrance
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seed production, Nursery & Gardening.pdf
This presentation offers a general idea of the structure of seed, seed production, management of seeds and its allied technologies. It also offers the concept of gene erosion and the practices used to control it. Nursery and gardening have been widely explored along with their importance in the related domain.
Evaluation and Identification of J'BaFofi the Giant Spider of Congo and Moke...
ABSTRACT
The J'BaFofi, or "Giant Spider," is a mainly legendary arachnid by reportedly inhabiting the dense rain forests of
the Congo. As despite numerous anecdotal accounts and cultural references, the scientific validation remains more elusive.
My study aims to proper evaluate the existence of the J'BaFofi through the analysis of historical reports,indigenous
testimonies and modern exploration efforts.
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted Brγ emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual H−K and K−L colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (≈15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20◦, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holes– stars: formation– Galaxy: center– galaxies: star formation
Hariyalikart Case Study of helping farmers in Bihar
Helping farmers all across India through our latest technologies of modern farming like drones for irrigation and best pest control For more visit : https://www.hariyalikart.com/case-study
TOPIC OF DISCUSSION: CENTRIFUGATION SLIDESHARE.pptx
Centrifugation is a powerful technique used in laboratories to separate components of a heterogeneous mixture based on their density. This process utilizes centrifugal force to rapidly spin samples, causing denser particles to migrate outward more quickly than lighter ones. As a result, distinct layers form within the sample tube, allowing for easy isolation and purification of target substances.
Explainable Deepfake Image/Video Detection
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Software available at https://github.com/IDT-ITI/XAI-Deepfakes
Physics Investigatory Project on transformers. Class 12th
Physics investigatory project on transformers with required details for 12thes. with index, theory, types of transformers (with relevant images), procedure, sources of error, aim n apparatus along with bibliography🗃️📜. Please try to add your own imagination rather than just copy paste... Hope you all guys friends n juniors' like it. peace out✌🏻✌🏻
Discovery of Merging Twin Quasars at z=6.05
We report the discovery of two quasars at a redshift of z = 6.05 in the process of merging. They were
serendipitously discovered from the deep multiband imaging data collected by the Hyper Suprime-Cam (HSC)
Subaru Strategic Program survey. The quasars, HSC J121503.42−014858.7 (C1) and HSC J121503.55−014859.3
(C2), both have luminous (>1043 erg s−1
) Lyα emission with a clear broad component (full width at half
maximum >1000 km s−1
). The rest-frame ultraviolet (UV) absolute magnitudes are M1450 = − 23.106 ± 0.017
(C1) and −22.662 ± 0.024 (C2). Our crude estimates of the black hole masses provide log 8.1 0. ( ) M M BH = 3
in both sources. The two quasars are separated by 12 kpc in projected proper distance, bridged by a structure in the
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reported to date, providing crucial insight into galaxy and black hole build-up in the hierarchical structure
formation scenario. A companion paper will present the gas and dust properties captured by Atacama Large
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Unified Astronomy Thesaurus concepts: Double quasars (406); Quasars (1319); Reionization (1383); High-redshift
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•Totalfoodgrainproductioninindiais311milliontonnesandstorageis145mt.InIndia,annualstoragelosseshavebeenestimated14mtworthofRs.7,000croreinwhichinsectsaloneaccountfornearlyRs.1,300crores.
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Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...
We present the JWST discovery of SN 2023adsy, a transient object located in a host galaxy JADES-GS
+
53.13485
−
27.82088
with a host spectroscopic redshift of
2.903
±
0.007
. The transient was identified in deep James Webb Space Telescope (JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) program. Photometric and spectroscopic followup with NIRCam and NIRSpec, respectively, confirm the redshift and yield UV-NIR light-curve, NIR color, and spectroscopic information all consistent with a Type Ia classification. Despite its classification as a likely SN Ia, SN 2023adsy is both fairly red (
�
(
�
−
�
)
∼
0.9
) despite a host galaxy with low-extinction and has a high Ca II velocity (
19
,
000
±
2
,
000
km/s) compared to the general population of SNe Ia. While these characteristics are consistent with some Ca-rich SNe Ia, particularly SN 2016hnk, SN 2023adsy is intrinsically brighter than the low-
�
Ca-rich population. Although such an object is too red for any low-
�
cosmological sample, we apply a fiducial standardization approach to SN 2023adsy and find that the SN 2023adsy luminosity distance measurement is in excellent agreement (
≲
1
�
) with
Λ
CDM. Therefore unlike low-
�
Ca-rich SNe Ia, SN 2023adsy is standardizable and gives no indication that SN Ia standardized luminosities change significantly with redshift. A larger sample of distant SNe Ia is required to determine if SN Ia population characteristics at high-
�
truly diverge from their low-
�
counterparts, and to confirm that standardized luminosities nevertheless remain constant with redshift.
BIRDS DIVERSITY OF SOOTEA BISWANATH ASSAM.ppt.pptx
Ahota Beel, nestled in Sootea Biswanath Assam , is celebrated for its extraordinary diversity of bird species. This wetland sanctuary supports a myriad of avian residents and migrants alike. Visitors can admire the elegant flights of migratory species such as the Northern Pintail and Eurasian Wigeon, alongside resident birds including the Asian Openbill and Pheasant-tailed Jacana. With its tranquil scenery and varied habitats, Ahota Beel offers a perfect haven for birdwatchers to appreciate and study the vibrant birdlife that thrives in this natural refuge.
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Wereport the study of a huge optical intraday flare on 2021 November 12 at 2 a.m. UT in the blazar OJ287. In the binary black hole model, it is associated with an impact of the secondary black hole on the accretion disk of the primary. Our multifrequency observing campaign was set up to search for such a signature of the impact based on a prediction made 8 yr earlier. The first I-band results of the flare have already been reported by Kishore et al. (2024). Here we combine these data with our monitoring in the R-band. There is a big change in the R–I spectral index by 1.0 ±0.1 between the normal background and the flare, suggesting a new component of radiation. The polarization variation during the rise of the flare suggests the same. The limits on the source size place it most reasonably in the jet of the secondary BH. We then ask why we have not seen this phenomenon before. We show that OJ287 was never before observed with sufficient sensitivity on the night when the flare should have happened according to the binary model. We also study the probability that this flare is just an oversized example of intraday variability using the Krakow data set of intense monitoring between 2015 and 2023. We find that the occurrence of a flare of this size and rapidity is unlikely. In machine-readable Tables 1 and 2, we give the full orbit-linked historical light curve of OJ287 as well as the dense monitoring sample of Krakow.
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Anti-Universe And Emergent Gravity and the Dark Universe
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional ‘dark’ gravitational force describing the ‘elastic’ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newton’s constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional ‘dark gravity force’ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
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The Limited Role of the Streaming Instability during Moon and Exomoon Formation
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Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
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ELISA and its advantages
- 1. Presented by: Farhana Akter Joty ID: 193-46-258
- 2. Prior to the development of the EIA/ELISA, the only option for conducting an immunoassay was radio immunoassay, a technique using radioactively-labeled antigens or antibodies. Avrameas (1966-1969) and Pierce (1967) developed methods to chemically link antibodies to biological enzymes whose activities produce a measurable signal with solutions containing appropriate substrates. This signal has to be associated with the presence of antibody or antigen .
- 3. Antibody Antigen Enzyme: Horse Radish Peroxidase (HRP), alkaline phosphate ( AP). Substrate: TMB (3,3',5,5', tetramethylbenzidine) The enzyme acts as a catalyst to oxidize substrate in the presence of Hydrogen peroxide to produce a blue color.
- 4. The basic enzyme-linked immunosorbent assay (ELISA), or enzyme immunoassay (EIA), is distinguished from other antibody-based assays because separation of specific and non-specific interactions occurs via serial binding to a solid surface, usually a polystyrene multiwell plate, and because quantitative results can be achieved. The ELISA procedure results in a colored end product which correlates to the amount of analyte present in the original sample.
- 5. The basic principle of an ELISA is to use an enzyme to detect the Ag-Ab binding (antigen- antibody binding). The enzyme converts a colorless substrate (chromogen) to a colored product, indicating the presence of Ag:Ab binding.
- 7. The ELISA assay yields different types of data output: Quantitative: ELISA data can be interpreted in comparison to a standard curve in order to precisely calculate the concentrations of antigen in various samples. Qualitative: ELISAs can also be used to achieve a yes or no answer indicating whether a particular antigen is present in a sample, as compared to a blank well containing no antigen or an unrelated control antigen.
- 8. Semi- quantitative: ELISAs can be used to compare the relative levels of antigen in assay samples, since the intensity of signal will vary directly with antigen concentration. The standard curve: ELISA data is typically graphed with optical density vs log concentration to produce a sigmoidal curve as shown in Figure. Known concentrations of antigen are used to produce a standard curve and then this data is used to measure the concentration of unknown samples by comparison to the linear portion of the standard curve. This can be done directly on the graph or with curve fitting software which is typically found on ELISA plate readers.
- 9. Figure : A typical ELISA curve
- 10. Screening donated blood for evidence of viral contamination by HIV-1 and HIV-2 (presence of anti-HIV antibodies) Hepatitis C (presence of antibodies) Hepatitis B (testing for both antibodies and a viral antigen) Measuring hormone levels HCG (as a test for pregnancy) LH (determining the time of ovulation) TSH, T3 and T4 (for thyroid function)