Validation of laboratory tests with important guidelinesVickshayo Sss
Validation ensures test methods are accurate and reliable. It establishes performance specifications and acceptance criteria. Methods are validated for accuracy, precision, reportable range, sensitivity and specificity using reference standards and statistical analysis. Pre-validation addresses purpose, guidelines and materials. Post-validation involves monitoring proficiency testing and system performance to maintain validity over time. Validation is important for conforming to standards, understanding error, and providing confidence in test results.
This document discusses measurement uncertainty. It defines measurement uncertainty as a parameter included with any measurement result that accounts for possible errors. It describes sources of uncertainty like sampling, storage conditions, and personal effects. The document outlines methods of calculating uncertainty using the standard deviation, and explains why assessing uncertainty is important for interpreting results and ensuring measurement quality. Measurement uncertainty is a key component of any measurement result.
This document discusses analytical methods validation as per ICH and USP guidelines. It provides an overview of the types of analytical procedures that require validation including identification tests, potency assays, limit tests, impurity tests, and specific tests. The key validation parameters discussed include specificity, accuracy, precision, linearity, range, limit of detection, limit of quantitation, ruggedness, and robustness. It also summarizes the objectives, types of procedures, and validation parameters for analytical method validation as defined by ICH and USP guidelines.
This document discusses sources of errors in quantitative analysis and methods to minimize errors. It defines:
1) Systematic errors which can affect results consistently, including personal, operational, instrumental, methodical, and additive/proportional errors.
2) Random errors due to limitations of instruments or observations. These can be minimized but not eliminated.
3) Methods to reduce errors including calibration, blanks, independent methods, and standard additions.
4) Expressing errors as absolute or relative values. Precision refers to agreement of repeated measurements while accuracy reflects agreement with true values.
This document discusses validation of sterilization equipment. It covers stages of validation including design qualification, installation qualification, operational qualification and performance qualification. Specific validation protocols are described for autoclaves and dry heat sterilizers. Heat distribution and heat penetration studies are important components to determine temperature uniformity within the equipment and establish sterilization conditions. Biological indicators are used to validate the sterilization process achieves sterility assurance levels.
Rapid Microbial Methods (RMM) offer pharmaceutical manufacturers the opportunity to improve the time to results (TTR) for testing in the microbial quality control lab. With growth-based methods, part of the validation process includes determination of the appropriate time-point to obtain comparable detection to the traditional method.
Dr. Andrew Sage outlines steps to perform this process using the Growth Direct System. Learn more at www.rapidmicrobio.com
This article introduces an oxygen transmission rate test method to test the pudding cup, i.e. the coulometric method. The test principle, instrument features, specifications, and testing procedures are all included in this article, which may provide reference for oxygen permeability test of packaging containers
Validation of laboratory tests with important guidelinesVickshayo Sss
Validation ensures test methods are accurate and reliable. It establishes performance specifications and acceptance criteria. Methods are validated for accuracy, precision, reportable range, sensitivity and specificity using reference standards and statistical analysis. Pre-validation addresses purpose, guidelines and materials. Post-validation involves monitoring proficiency testing and system performance to maintain validity over time. Validation is important for conforming to standards, understanding error, and providing confidence in test results.
This document discusses measurement uncertainty. It defines measurement uncertainty as a parameter included with any measurement result that accounts for possible errors. It describes sources of uncertainty like sampling, storage conditions, and personal effects. The document outlines methods of calculating uncertainty using the standard deviation, and explains why assessing uncertainty is important for interpreting results and ensuring measurement quality. Measurement uncertainty is a key component of any measurement result.
This document discusses analytical methods validation as per ICH and USP guidelines. It provides an overview of the types of analytical procedures that require validation including identification tests, potency assays, limit tests, impurity tests, and specific tests. The key validation parameters discussed include specificity, accuracy, precision, linearity, range, limit of detection, limit of quantitation, ruggedness, and robustness. It also summarizes the objectives, types of procedures, and validation parameters for analytical method validation as defined by ICH and USP guidelines.
This document discusses sources of errors in quantitative analysis and methods to minimize errors. It defines:
1) Systematic errors which can affect results consistently, including personal, operational, instrumental, methodical, and additive/proportional errors.
2) Random errors due to limitations of instruments or observations. These can be minimized but not eliminated.
3) Methods to reduce errors including calibration, blanks, independent methods, and standard additions.
4) Expressing errors as absolute or relative values. Precision refers to agreement of repeated measurements while accuracy reflects agreement with true values.
This document discusses validation of sterilization equipment. It covers stages of validation including design qualification, installation qualification, operational qualification and performance qualification. Specific validation protocols are described for autoclaves and dry heat sterilizers. Heat distribution and heat penetration studies are important components to determine temperature uniformity within the equipment and establish sterilization conditions. Biological indicators are used to validate the sterilization process achieves sterility assurance levels.
Rapid Microbial Methods (RMM) offer pharmaceutical manufacturers the opportunity to improve the time to results (TTR) for testing in the microbial quality control lab. With growth-based methods, part of the validation process includes determination of the appropriate time-point to obtain comparable detection to the traditional method.
Dr. Andrew Sage outlines steps to perform this process using the Growth Direct System. Learn more at www.rapidmicrobio.com
This article introduces an oxygen transmission rate test method to test the pudding cup, i.e. the coulometric method. The test principle, instrument features, specifications, and testing procedures are all included in this article, which may provide reference for oxygen permeability test of packaging containers
Item 2. Verification and Validation of Analytical MethodsSoils FAO-GSP
This document discusses the validation and verification of analytical test methods used at the Environmental Analysis Laboratory at Southern Cross University. It provides details on key validation parameters including accuracy, precision, selectivity, linearity, matrix effects, sensitivity, spike recoveries, trueness, range, ruggedness, and measurement uncertainty. Validation data is presented for methods analyzing metals and salts in freshwater, effluent, and wastewater samples by ICP-MS. The methods were verified to meet performance criteria in these sample matrices.
This document provides an overview of qualification of gas chromatography. It defines qualification and describes the types, which include design qualification, installation qualification, operational qualification, and performance qualification. It then gives details on qualification levels for gas chromatography equipment, including level III periodic checks. Examples of specific tests are provided to check parameters of the inlet system, oven, and detector against typical tolerance limits. Overall tests 1, 2A, and 2B are also described that can check multiple parameters at once.
1. Steps in analysis include deciding on a method, sample preparation, calibration, measurement, and evaluating results.
2. Samples can be classified based on size as macro, semi-micro, micro, or ultra-micro.
3. Quantitative analysis involves volumetric, gravimetric, or other instrumental methods to compute the quantity of a constituent.
This document discusses different types of errors that can occur in pharmaceutical analysis. There are two main categories of errors: determinate (systematic) errors and indeterminate (random) errors. Determinate errors have identifiable causes and include personal errors, instrumental errors, reagent errors, and errors due to methodology. Indeterminate errors cannot be identified and include random fluctuations. The document provides examples of different types of errors and methods that can be used to minimize errors, such as calibration, blank determinations, and using multiple analytical methods.
This document discusses key requirements for blood gas laboratories from the College of American Pathologists checklist. It outlines three main learning objectives: 1) developing valid means to compare blood gas analyzers and confirm their measurement ranges, 2) reviewing quality control results to detect instrument differences early, and 3) instituting procedures to detect and prevent preanalytical variation in blood gas results. The document then examines specific checklist items and notes regarding sample collection, instrument calibration and maintenance, proficiency testing, method comparisons, and quality management - emphasizing differences for blood gas analyses given sample instability.
This document provides information on qualification of gas chromatography equipment. It defines qualification as proving and documenting that equipment works correctly and leads to expected results. The types of qualification are design, installation, operational, and performance qualification. Installation qualification checks the installation site and equipment specifications. Operational qualification includes procedures to verify the system operates as intended. Performance qualification ensures the instrument performs within specified limits based on approved methods. The document then provides examples of tests and acceptance limits to check parameters of the gas chromatography inlet system, oven, and detector during periodic qualification.
This document provides an overview of liquid penetrant testing (PT), including its basic principles and procedures. Some key points:
- PT involves applying a penetrant containing a dye to detect surface-breaking flaws via capillary action. Excess penetrant is removed and developer applied to reveal indications.
- PT can detect discontinuities open to the surface in many materials. It is often used when other NDT methods are not suitable due to part geometry, material properties, or test environment.
- The basic PT procedure involves pre-cleaning, applying penetrant, removing excess, applying developer, and inspecting for indications. Proper technique and clean surfaces are critical for success.
Errors - pharmaceutical analysis -1, bpharm 1st semester, notes, topic errors
full details and answer about error
TN DR MGR UNIVERSITY
by Kumaran.M.pharm, professor
The document discusses the qualification of gas chromatography equipment. It defines qualification and describes the types including design, installation, operational, and performance qualification. It provides details on installation qualification, operational qualification, and performance qualification. The document then discusses qualification of GC equipment specifically, outlining the objectives and levels of qualification. It provides examples of tests and parameters to check at each level, including for the inlet system, oven, and detector, with typical tolerance limits. The tests include overall tests to check multiple parameters at once.
The document provides an overview of packaging validations according to ISO 11607 Part 1. It discusses determining appropriate sample sizes based on statistically valid rationales and factors to consider. It also covers writing a validation protocol, developing a test plan, test method options, family grouping, worst-case considerations, and creating validation samples. The document aims to provide guidance on conducting packaging validations in compliance with ISO 11607 standards.
Today's Topic Errors - Introduction, Sources of Errors, Types of Errors, Minimization of Errors, Accuracy, Precision, Significant Figures in Pharmaceutical Analysis subject in B.pharmacy 1st year as per JNTUA Syllabus...
This document outlines the key steps in method validation for clinical chemistry laboratories. It defines method validation and discusses when methods should be validated. The key aspects that must be validated include calibration, precision, accuracy, linearity, limit of detection, analytical range, sensitivity, specificity, ruggedness and robustness. Thorough documentation of the validation study is also required. Validating a method involves experimentally testing these parameters and documenting the results to provide objective evidence that the method is suitable for its intended use.
This document provides an overview of recent developments in top-down approaches for evaluating measurement uncertainty in testing laboratories. It discusses the strengths and weaknesses of the traditional bottom-up GUM method and introduces several top-down methods including those based on precision, accuracy and trueness using quality control data; control chart methods; the use of validation data and reference materials; and experience-based models like Horwitz's equation. The document provides details on how measurement uncertainty is estimated using these various top-down approaches.
The document discusses various types of errors that can occur in quantitative chemical analysis, including random errors, systematic errors, determinate errors, indeterminate errors, and errors due to faulty instrumentation, impure reagents, or improper methodology. It also describes ways to minimize errors, such as calibrating apparatus, running blanks and controls, using multiple analytical techniques, and performing replicate measurements. Accuracy is defined as how close a measurement is to the true value, while precision refers to the reproducibility of measurements.
This presentation provides important information on mercury and where it can be found, as well as strategies for measuring vapor levels and remediation techniques. At the end of the presentation, you'll find real-world case studies that will drive these lessons home.
The document provides an overview of the qualification process for high performance liquid chromatography (HPLC) equipment, including design qualification (DQ), installation qualification (IQ), operational qualification (OQ), and performance qualification (PQ). It describes the objectives and procedures for each qualification step. Key aspects covered include verifying design specifications, proper installation, operational requirements such as precision, accuracy and noise levels, and ongoing performance monitoring. The goal of qualification is to ensure analytical systems are suitable for their intended use and generate reliable results.
The document discusses measurement quality assurance and reducing risks from in-tolerance measurement errors. It explains the concepts of in-tolerance measurement risk and guard bands, using an example of temperature measurements on a heart-lung bypass machine. While an in-tolerance calibration result may not flag an issue, product measurements could still be incorrect if the instrument drifted within its tolerance range. The document recommends using an instrument with accuracy at least 4 times better than the process tolerance and establishing guard bands to reduce the need for costly non-conformance investigations when drift occurs.
This document provides an overview of melt flow testing based on ISO 1133 and ASTM D1238 standards. Melt flow testing measures the mass or volume of melted polymer that flows through a die in 10 minutes at a specified temperature. It is commonly used for quality control of thermoplastics to verify materials, check quality, compare new materials, and predict polymer processing behavior. Key factors that can influence melt flow results include temperature accuracy and stability, sample preparation and compaction, density value used, cleaning procedures, and manual versus automatic test operations.
This document provides an overview of melt flow testing based on ISO 1133 and ASTM D1238 standards. Melt flow testing measures the mass or volume of melted polymer that flows through a die in 10 minutes at a specified temperature. It is commonly used for quality control of thermoplastics to verify materials, check quality, compare new materials, and predict polymer processing behavior. Key factors that can influence melt flow results include temperature accuracy and stability, sample preparation and moisture content, compaction method, density value used, manual test operations, die and piston maintenance, and cleaning procedures.
Item 2. Verification and Validation of Analytical MethodsSoils FAO-GSP
This document discusses the validation and verification of analytical test methods used at the Environmental Analysis Laboratory at Southern Cross University. It provides details on key validation parameters including accuracy, precision, selectivity, linearity, matrix effects, sensitivity, spike recoveries, trueness, range, ruggedness, and measurement uncertainty. Validation data is presented for methods analyzing metals and salts in freshwater, effluent, and wastewater samples by ICP-MS. The methods were verified to meet performance criteria in these sample matrices.
This document provides an overview of qualification of gas chromatography. It defines qualification and describes the types, which include design qualification, installation qualification, operational qualification, and performance qualification. It then gives details on qualification levels for gas chromatography equipment, including level III periodic checks. Examples of specific tests are provided to check parameters of the inlet system, oven, and detector against typical tolerance limits. Overall tests 1, 2A, and 2B are also described that can check multiple parameters at once.
1. Steps in analysis include deciding on a method, sample preparation, calibration, measurement, and evaluating results.
2. Samples can be classified based on size as macro, semi-micro, micro, or ultra-micro.
3. Quantitative analysis involves volumetric, gravimetric, or other instrumental methods to compute the quantity of a constituent.
This document discusses different types of errors that can occur in pharmaceutical analysis. There are two main categories of errors: determinate (systematic) errors and indeterminate (random) errors. Determinate errors have identifiable causes and include personal errors, instrumental errors, reagent errors, and errors due to methodology. Indeterminate errors cannot be identified and include random fluctuations. The document provides examples of different types of errors and methods that can be used to minimize errors, such as calibration, blank determinations, and using multiple analytical methods.
This document discusses key requirements for blood gas laboratories from the College of American Pathologists checklist. It outlines three main learning objectives: 1) developing valid means to compare blood gas analyzers and confirm their measurement ranges, 2) reviewing quality control results to detect instrument differences early, and 3) instituting procedures to detect and prevent preanalytical variation in blood gas results. The document then examines specific checklist items and notes regarding sample collection, instrument calibration and maintenance, proficiency testing, method comparisons, and quality management - emphasizing differences for blood gas analyses given sample instability.
This document provides information on qualification of gas chromatography equipment. It defines qualification as proving and documenting that equipment works correctly and leads to expected results. The types of qualification are design, installation, operational, and performance qualification. Installation qualification checks the installation site and equipment specifications. Operational qualification includes procedures to verify the system operates as intended. Performance qualification ensures the instrument performs within specified limits based on approved methods. The document then provides examples of tests and acceptance limits to check parameters of the gas chromatography inlet system, oven, and detector during periodic qualification.
This document provides an overview of liquid penetrant testing (PT), including its basic principles and procedures. Some key points:
- PT involves applying a penetrant containing a dye to detect surface-breaking flaws via capillary action. Excess penetrant is removed and developer applied to reveal indications.
- PT can detect discontinuities open to the surface in many materials. It is often used when other NDT methods are not suitable due to part geometry, material properties, or test environment.
- The basic PT procedure involves pre-cleaning, applying penetrant, removing excess, applying developer, and inspecting for indications. Proper technique and clean surfaces are critical for success.
Errors - pharmaceutical analysis -1, bpharm 1st semester, notes, topic errors
full details and answer about error
TN DR MGR UNIVERSITY
by Kumaran.M.pharm, professor
The document discusses the qualification of gas chromatography equipment. It defines qualification and describes the types including design, installation, operational, and performance qualification. It provides details on installation qualification, operational qualification, and performance qualification. The document then discusses qualification of GC equipment specifically, outlining the objectives and levels of qualification. It provides examples of tests and parameters to check at each level, including for the inlet system, oven, and detector, with typical tolerance limits. The tests include overall tests to check multiple parameters at once.
The document provides an overview of packaging validations according to ISO 11607 Part 1. It discusses determining appropriate sample sizes based on statistically valid rationales and factors to consider. It also covers writing a validation protocol, developing a test plan, test method options, family grouping, worst-case considerations, and creating validation samples. The document aims to provide guidance on conducting packaging validations in compliance with ISO 11607 standards.
Today's Topic Errors - Introduction, Sources of Errors, Types of Errors, Minimization of Errors, Accuracy, Precision, Significant Figures in Pharmaceutical Analysis subject in B.pharmacy 1st year as per JNTUA Syllabus...
This document outlines the key steps in method validation for clinical chemistry laboratories. It defines method validation and discusses when methods should be validated. The key aspects that must be validated include calibration, precision, accuracy, linearity, limit of detection, analytical range, sensitivity, specificity, ruggedness and robustness. Thorough documentation of the validation study is also required. Validating a method involves experimentally testing these parameters and documenting the results to provide objective evidence that the method is suitable for its intended use.
This document provides an overview of recent developments in top-down approaches for evaluating measurement uncertainty in testing laboratories. It discusses the strengths and weaknesses of the traditional bottom-up GUM method and introduces several top-down methods including those based on precision, accuracy and trueness using quality control data; control chart methods; the use of validation data and reference materials; and experience-based models like Horwitz's equation. The document provides details on how measurement uncertainty is estimated using these various top-down approaches.
The document discusses various types of errors that can occur in quantitative chemical analysis, including random errors, systematic errors, determinate errors, indeterminate errors, and errors due to faulty instrumentation, impure reagents, or improper methodology. It also describes ways to minimize errors, such as calibrating apparatus, running blanks and controls, using multiple analytical techniques, and performing replicate measurements. Accuracy is defined as how close a measurement is to the true value, while precision refers to the reproducibility of measurements.
This presentation provides important information on mercury and where it can be found, as well as strategies for measuring vapor levels and remediation techniques. At the end of the presentation, you'll find real-world case studies that will drive these lessons home.
The document provides an overview of the qualification process for high performance liquid chromatography (HPLC) equipment, including design qualification (DQ), installation qualification (IQ), operational qualification (OQ), and performance qualification (PQ). It describes the objectives and procedures for each qualification step. Key aspects covered include verifying design specifications, proper installation, operational requirements such as precision, accuracy and noise levels, and ongoing performance monitoring. The goal of qualification is to ensure analytical systems are suitable for their intended use and generate reliable results.
The document discusses measurement quality assurance and reducing risks from in-tolerance measurement errors. It explains the concepts of in-tolerance measurement risk and guard bands, using an example of temperature measurements on a heart-lung bypass machine. While an in-tolerance calibration result may not flag an issue, product measurements could still be incorrect if the instrument drifted within its tolerance range. The document recommends using an instrument with accuracy at least 4 times better than the process tolerance and establishing guard bands to reduce the need for costly non-conformance investigations when drift occurs.
This document provides an overview of melt flow testing based on ISO 1133 and ASTM D1238 standards. Melt flow testing measures the mass or volume of melted polymer that flows through a die in 10 minutes at a specified temperature. It is commonly used for quality control of thermoplastics to verify materials, check quality, compare new materials, and predict polymer processing behavior. Key factors that can influence melt flow results include temperature accuracy and stability, sample preparation and compaction, density value used, cleaning procedures, and manual versus automatic test operations.
This document provides an overview of melt flow testing based on ISO 1133 and ASTM D1238 standards. Melt flow testing measures the mass or volume of melted polymer that flows through a die in 10 minutes at a specified temperature. It is commonly used for quality control of thermoplastics to verify materials, check quality, compare new materials, and predict polymer processing behavior. Key factors that can influence melt flow results include temperature accuracy and stability, sample preparation and moisture content, compaction method, density value used, manual test operations, die and piston maintenance, and cleaning procedures.
Similar to MEASUREMENT UNCERTAINTY (Gold testing labs).pptx (20)
PPT on Direct Seeded Rice presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024.
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDSSérgio Sacani
The pathway(s) to seeding the massive black holes (MBHs) that exist at the heart of galaxies in the present and distant Universe remains an unsolved problem. Here we categorise, describe and quantitatively discuss the formation pathways of both light and heavy seeds. We emphasise that the most recent computational models suggest that rather than a bimodal-like mass spectrum between light and heavy seeds with light at one end and heavy at the other that instead a continuum exists. Light seeds being more ubiquitous and the heavier seeds becoming less and less abundant due the rarer environmental conditions required for their formation. We therefore examine the different mechanisms that give rise to different seed mass spectrums. We show how and why the mechanisms that produce the heaviest seeds are also among the rarest events in the Universe and are hence extremely unlikely to be the seeds for the vast majority of the MBH population. We quantify, within the limits of the current large uncertainties in the seeding processes, the expected number densities of the seed mass spectrum. We argue that light seeds must be at least 103 to 105 times more numerous than heavy seeds to explain the MBH population as a whole. Based on our current understanding of the seed population this makes heavy seeds (Mseed > 103 M⊙) a significantly more likely pathway given that heavy seeds have an abundance pattern than is close to and likely in excess of 10−4 compared to light seeds. Finally, we examine the current state-of-the-art in numerical calculations and recent observations and plot a path forward for near-future advances in both domains.
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...Scintica Instrumentation
Targeting Hsp90 and its pathogen Orthologs with Tethered Inhibitors as a Diagnostic and Therapeutic Strategy for cancer and infectious diseases with Dr. Timothy Haystead.
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...Advanced-Concepts-Team
Presentation in the Science Coffee of the Advanced Concepts Team of the European Space Agency on the 07.06.2024.
Speaker: Diego Blas (IFAE/ICREA)
Title: Gravitational wave detection with orbital motion of Moon and artificial
Abstract:
In this talk I will describe some recent ideas to find gravitational waves from supermassive black holes or of primordial origin by studying their secular effect on the orbital motion of the Moon or satellites that are laser ranged.
The debris of the ‘last major merger’ is dynamically youngSérgio Sacani
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
Anti-Universe And Emergent Gravity and the Dark UniverseSérgio Sacani
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.
Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
It is defined as the relationship in which each organism in interaction gets benefits from association. It is an obligatory relationship in which mutualist and host are metabolically dependent on each other.
Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
Relationship of mutualism allows organisms to exist in habitat that could not occupied by either species alone.
Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:
i. Lichens:
Lichens are excellent example of mutualism.
They are the association of specific fungi and certain genus of algae. In lichen, fungal partner is called mycobiont and algal partner is called
II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
In this theoretical example of syntrophism, population 1 is able to utilize and metabolize compound A, forming compound B but cannot metabolize beyond compound B without co-operation of population 2. Population 2is unable to utilize compound A but it can metabolize compound B forming compound C. Then both population 1 and 2 are able to carry out metabolic reaction which leads to formation of end product that neither population could produce alone.
Examples of syntrophism:
i. Methanogenic ecosystem in sludge digester
Methane produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria.
Anaerobic fermentative bacteria generate CO2 and H2 utilizing carbohydrates which is then utilized by methanogenic bacteria (Methanobacter) to produce methane.
ii. Lactobacillus arobinosus and Enterococcus faecalis:
In the minimal media, Lactobacillus arobinosus and Enterococcus faecalis are able to grow together but not alone.
The synergistic relationship between E. faecalis and L. arobinosus occurs in which E. faecalis require folic acid
The binding of cosmological structures by massless topological defectsSérgio Sacani
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
The cost of acquiring information by natural selectionCarl Bergstrom
This is a short talk that I gave at the Banff International Research Station workshop on Modeling and Theory in Population Biology. The idea is to try to understand how the burden of natural selection relates to the amount of information that selection puts into the genome.
It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...Sérgio Sacani
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
2. What is Measurement Uncertainty(MU)?
Definition: The margin of doubt that exists for the result of any measurement, as well as how
significant the doubt is.
In simple terms: It is the error in measurement , that is unavoidable and should be
accounted for in testing.
3. Terms associated with MU
• Trueness- Theoretical scientific value that cannot be obtained
practically. E.g. theoretical density of water is 1 g/cmᶟ but rather the
experimental average is 0.9998 g/cmᶟ.
• Accuracy- the closeness of experimental results to the true value.
• Precise- the closeness of experimental results to each other.
Source: CNX Introduction to CHEM
QUESTION: Which one is more important between Precision & Accuracy?
5. 2 Types of Errors in MU
• 1.Random Errors
These are caused by unknown and unpredictable changes in the
experiment. This may include:
• temperature changes
• air pressure changes
• other environmental changes etc
6. 2 Types of Errors in MU
• 2.Systematic Errors
These result mostly from measuring devices being worn out or are out of
calibration.
Systematic errors may include:
• Calibration changes
• Instrument errors
• Change of standards used in calibration
• Wrong experiment procedures
• Incorrectly prepared reagents
7. Example of MU inception in Gold Cupellation
Fire Assay Method
• Preparation of Nitric acid solution for partying (gold-silver separation)
8. Example of MU inception in Gold Cupellation
Fire Assay Method
• Weighing of sample, silver and copper.
9. Example of MU inception in Gold Cupellation
Fire Assay Method
• Folding of samples in lead cones
10. Example of MU inception in Gold Cupellation
Fire Assay Method
• Placing samples in the furnace.
11. Example of MU inception in Gold Cupellation
Fire Assay Method
• Hammering of beads
12. Example of MU inception in Gold Cupellation
Fire Assay Method
• Stripping of beads
13. Example of MU inception in Gold Cupellation
Fire Assay Method
• Partying timing (Au-Ag separation) using nitric acid
14. Example of MU inception in Gold Cupellation
Fire Assay Method
• LIMS software
15. Example of MU inception in Gold Cupellation
Fire Assay Method
• Lab ventilation and conditions
• (temp & humidity)
NB: The mentioned uncertainties
Are not the only ones, a lot more
remain!!
16. ISO17025:2017 standard comments on MU
Clause 7.2.1
The laboratory shall use appropriate methods and procedures for all laboratory activities and, where
appropriate, for evaluation of the measurement uncertainty as well as statistical techniques for analysis
of data.
Clause 7.2.2.1.f Method validation shall be as extensive as necessary including:
evaluation of measurement uncertainty of the results based on an understanding of the theoretical
principles of the method and practical experience of the performance of the sampling or test method.
NOTES: According to the ISO standard, It is mandatory to prioritize MU and its evaluation in a testing lab,
especially that is accredited.
17. 7 Basic steps to determine MU
1.Specify the Measurement Process.
2.Identify Sources of Uncertainty.
3.Quantify Sources of Uncertainty.
4.Characterize Sources of Uncertainty.
5.Convert Uncertainties to Standard Deviations.
6.Calculate the Combined Uncertainty.
7.Calculate the Expanded Uncertainty.
18. General formula for calculation of mu
• Measurement Uncertainty (MU) = √ [∑ (xi – μ)2 / (n * (n-1))]
• Where xi is reading(measured value)
μ is mean
n is number of tests