Recognition of Earthquake-Prone Areas: Validity of Results Obtained from 1972 to 2000

2013 ◽  
pp. 37-44 ◽  
Author(s):  
A. I. Gorshkov ◽  
V. G. Kossobokov ◽  
E. Ya. Rantsman ◽  
A. A. Soloviev
Keyword(s):  
Validity Of Results

Clinical Update: Functional Capacity Evaluations and Disability

1998 ◽  
Vol 3 (2) ◽  
pp. 4-5
Author(s):  
Glenn Pransky
Keyword(s):  
Direct Observation ◽  
Functional Capacity ◽  
Work Capacity ◽  
Functional Capacity Evaluation ◽  
Whole Body ◽  
Validity Of Results ◽  
Job Tasks ◽  
Capacity Evaluation ◽  
Physical Abilities ◽  
The Relationship

Abstract According to the AMA Guides to the Evaluation of Permanent Impairment, a functional capacity evaluation (FCE) measures an individual's physical abilities via a set of activities in a structured setting and provides objective data about the relationship between an impairment and maximal ability to perform work activities. A key distinction between FCEs and self-reported activities of daily living is that the former involve direct observation by professional evaluators. Numerous devices can quantify the physical function of a specific part of the musculoskeletal system but do not address the performance of whole body tasks in the workplace, and these devices have not been shown to predict accurately the ability to perform all but the simplest job tasks. Information about reliability has been proposed as a way to identify magnification and malingering, but variability due to pain and poor comprehension of instructions may cause variations in assessments. Structured work capacity evaluations involve a set of activities but likely underestimate the individual's ability to do jobs that involve complex or varying activities. Job simulations involve direct observation of an individual performing actual job tasks, require a skilled and experienced evaluator, and raise questions about expense, time, objectivity and validity of results, and interpretation of results in terms of the ability to perform specific jobs. To understand the barriers to return to work, examiners must supplement FCEs with information regarding workplace environment, accommodations, and demotivators.

scholarly journals Effects of Variable Transport Properties on Heat and Mass Transfer in MHD Bioconvective Nanofluid Rheology with Gyrotactic Microorganisms: Numerical Approach

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 231
Author(s):  
Muhammad Awais ◽  
Saeed Ehsan Awan ◽  
Muhammad Asif Zahoor Raja ◽  
Nabeela Parveen ◽  
Wasim Ullah Khan ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Transport Properties ◽  
Heat And Mass Transfer ◽  
Group Analysis ◽  
Numerical Approach ◽  
Validity Of Results ◽  
Gyrotactic Microorganisms ◽  
Transfer Rates ◽  
Buongiorno’S Model ◽  
Density Distributions

Rheology of MHD bioconvective nanofluid containing motile microorganisms is inspected numerically in order to analyze heat and mass transfer characteristics. Bioconvection is implemented by combined effects of magnetic field and buoyancy force. Gyrotactic microorganisms enhance the heat and transfer as well as perk up the nanomaterials’ stability. Variable transport properties along with assisting and opposing flow situations are taken into account. The significant influences of thermophoresis and Brownian motion have also been taken by employing Buongiorno’s model of nanofluid. Lie group analysis approach is utilized in order to compute the absolute invariants for the system of differential equations, which are solved numerically using Adams-Bashforth technique. Validity of results is confirmed by performing error analysis. Graphical and numerical illustrations are prepared in order to get the physical insight of the considered analysis. It is observed that for controlling parameters corresponding to variable transport properties c2, c4, c6, and c8, the velocity, temperature, concentration, and bioconvection density distributions accelerates, respectively. While heat and mass transfer rates increases for convection parameter and bioconvection Rayleigh number, respectively.

scholarly journals Determination of Trimetazidine Dihydrochloride in the Presence of Its Acid-Induced Degradation Products

2004 ◽  
Vol 87 (4) ◽  
pp. 827-833 ◽  
Author(s):  
Lories I Bebawy ◽  
Mohammed F El Tarras ◽  
Samah A El Sabour
Keyword(s):  
Degradation Products ◽  
Standard Addition ◽  
Validity Of Results ◽  
Pharmaceutical Dosage Forms ◽  
First Derivative ◽  
The Third ◽  
Bulk Powder ◽  
Intact Drug ◽  
Trimetazidine Dihydrochloride

Abstract Three methods are presented for the determination of trimetazidine dihydrochloride in the presence of its acid-induced degradation products. The first method was based on measurement of first-derivative D1 value of trimetazidine dihydrochloride at 282 nm over a concentration range of 8.00–56.00 μg/mL with mean percentage accuracy of 99.80 ± 1.17. The second method was based on first derivative of the ratio spectra DD1 at 282 nm over the same concentration range with the percentage accuracy of 99.14 ± 0.68. The third method was based on separation of trimetazidine dihydrochloride from its acid-induced degradation products followed by densitometric measurement of the spots at 215 nm. The separation was performed on silica gel 60 F254 using methanol–ammonia (100 + 1.5, v/v) as mobile phase. This method was applicable for determination of the intact drug in the presence of its degradation products over a concentration range of 2.00–9.00 μg/spot with mean percentage accuracy of 99.86 ± 0.92. The proposed methods were successfully applied for the determination of trimetazidine dihydrochloride in bulk powder, laboratory-prepared mixtures containing different percentages of degradation products, and pharmaceutical dosage forms. The validity of results was assessed by applying the standard addition technique. The results obtained agreed statistically with those obtained by the reported method.

Exploring the process of workplace bullying in Indian organizations

2017 ◽  
Vol 6 (3) ◽  
pp. 247-273 ◽  
Author(s):  
Arpana Rai ◽  
Upasna A. Agarwal
Keyword(s):  
Grounded Theory ◽  
Workplace Bullying ◽  
Study Data ◽  
Support Network ◽  
Theory Approach ◽  
Validity Of Results ◽  
Content Type ◽  
Hrm Practices ◽  
Bullying Policy ◽  
The Social

Purpose The purpose of this paper is to explore the process of workplace bullying in Indian organizations from the victims’ perspective. Design/methodology/approach The study adopted the grounded theory approach and centered on the participants’ experiences, interpretations, and reactions toward bullying. In total, 23 self-reported victims formed the sample of the study. Data from interviews were analyzed using the coding procedure of grounded theory methodology. To enhance the validity of results, in addition to interviews, member checking technique was also used. Findings The study revealed that the process of workplace bullying in Indian organizations can be broadly explained in four sequential phases: exposure and confusion over mistreatment; making attributions; utilizing options within the organization; and adjustment with the current situation. The findings highlight the importance of sense-making, the social support network, complexity of coping behaviors, silence motives of employees as well as negative and nourishing effects of workplace bullying. The role of culture is visible in the bullying dynamics. Research limitations/implications The study examined bullying from the victims’ perspective; however, perpetrator and bystanders’ perspective would have added interesting insights into the findings. Practical implications The findings point toward the rhetoric of HRM practices in Indian organizations. A well formulated and implemented anti-bullying policy will reduce the rhetoric of HRM practices in Indian organizations. Originality/value The present study contributes to the limited literature on the process of workplace bullying by exploring the process in a new national context (India).

scholarly journals Revisiting Gaussian copulas to handle endogenous regressors

2021 ◽  
Author(s):  
Jan-Michael Becker ◽  
Dorian Proksch ◽  
Christian M. Ringle
Keyword(s):  
Regression Models ◽  
Statistical Power ◽  
Multilevel Models ◽  
Gaussian Copula ◽  
Simulation Studies ◽  
Validity Of Results ◽  
Endogenous Regressors ◽  
Copula Approach ◽  
Original Presentation ◽  
And Performance

AbstractMarketing researchers are increasingly taking advantage of the instrumental variable (IV)-free Gaussian copula approach. They use this method to identify and correct endogeneity when estimating regression models with non-experimental data. The Gaussian copula approach’s original presentation and performance demonstration via a series of simulation studies focused primarily on regression models without intercept. However, marketing and other disciplines’ researchers mainly use regression models with intercept. This research expands our knowledge of the Gaussian copula approach to regression models with intercept and to multilevel models. The results of our simulation studies reveal a fundamental bias and concerns about statistical power at smaller sample sizes and when the approach’s primary assumptions are not fully met. This key finding opposes the method’s potential advantages and raises concerns about its appropriate use in prior studies. As a remedy, we derive boundary conditions and guidelines that contribute to the Gaussian copula approach’s proper use. Thereby, this research contributes to ensuring the validity of results and conclusions of empirical research applying the Gaussian copula approach.

scholarly journals Why most Principal Component Analyses (PCA) in population genetic studies are wrong

2021 ◽  
Author(s):  
Eran Elhaik
Keyword(s):  
Population Genetics ◽  
Population Genetic ◽  
Genetic Model ◽  
Principal Component ◽  
Population Data ◽  
Test Cases ◽  
Validity Of Results ◽  
Genetic Studies ◽  
Minimal Loss ◽  
Admixture Population

Principal Component Analysis (PCA) is a multivariate analysis that allows reduction of the complexity of datasets while preserving data's covariance and visualizing the information on colorful scatterplots, ideally with only a minimal loss of information. PCA applications are extensively used as the foremost analyses in population genetics and related fields (e.g., animal and plant or medical genetics), implemented in well-cited packages like EIGENSOFT and PLINK. PCA outcomes are used to shape study design, identify and characterize individuals and populations, and draw historical and ethnobiological conclusions on origins, evolution, whereabouts, and relatedness. The replicability crisis in science has prompted us to evaluate whether PCA results are reliable, robust, and replicable. We employed an intuitive color-based model alongside human population data for eleven common test cases. We demonstrate that PCA results are artifacts of the data and that they can be easily manipulated to generate desired outcomes. PCA results may not be reliable, robust, or replicable as the field assumes. Our findings raise concerns on the validity of results reported in the literature of population genetics and related fields that place a disproportionate reliance upon PCA outcomes and the insights derived from them. We conclude that PCA may have a biasing role in genetic investigations. An alternative mixed-admixture population genetic model is discussed.

scholarly journals Guidelines on how to assess the validity of results presented in subgroup analysis of clinical trials

2002 ◽  
Vol 57 (2) ◽  
pp. 83-88 ◽  
Author(s):  
Edson Duarte Moreira ◽  
Ezra Susser
Keyword(s):  
Clinical Trial ◽  
Clinical Trials ◽  
Randomized Clinical Trial ◽  
Subgroup Analysis ◽  
Observational Studies ◽  
Randomized Clinical Trials ◽  
Usual Method ◽  
Validity Of Results ◽  
Results Of Treatment ◽  
Trial Participants

In observational studies, identification of associations within particular subgroups is the usual method of investigation. As an exploratory method, it is the bread and butter of epidemiological research. Nearly everything that has been learned in epidemiology has been derived from the analysis of subgroups. In a randomized clinical trial, the entire purpose is the comparison of the test subjects and the controls, and when there is particular interest in the results of treatment in a certain section of trial participants, a subgroup analysis is performed. These subgroups are examined to see if they are liable to a greater benefit or risk from treatment. Thus, analyzing patient subsets is a natural part of the process of improving therapeutic knowledge through clinical trials. Nevertheless, the reliability of subgroup analysis can often be poor because of problems of multiplicity and limitations in the numbers of patients studied. The naive interpretation of the results of such examinations is a cause of great confusion in the therapeutic literature. We emphasize the need for readers to be aware that inferences based on comparisons between subgroups in randomized clinical trials should be approached more cautiously than those based on the main comparison. That is, subgroup analysis results derived from a sound clinical trial are not necessarily valid; one must not jump to conclusions and accept the validity of subgroup analysis results without an appropriate judgment.

Methodological Problems in Measuring Ambulation in the Open Field

1963 ◽  
Vol 13 (3) ◽  
pp. 907-912 ◽  
Author(s):  
Norman D. Henderson
Keyword(s):  
Open Field ◽  
Time Of Day ◽  
Behavioral Measures ◽  
Validity Of Results ◽  
Observer Bias ◽  
Control Procedures ◽  
Systematic Biases ◽  
Methodological Problems

Three factors often ignored by investigators measuring ambulation in an open field are litter differences, observer bias, and time of day of testing. Evidence is given to show that each of these factors can have a significant effect on ambulation scores in the open field, and failure to control these factors can lead to systematic biases which would decrease the validity of results. Despite the importance of these factors, in a sample of 40 recent studies a majority of experiments failed to mention any control procedures for two or more of these variables. This failure is particularly serious when there is a lack of other behavioral measures supporting conclusions based on ambulation data.

scholarly journals Optimising experimental research in respiratory diseases: an ERS statement

2018 ◽  
Vol 51 (5) ◽  
pp. 1702133 ◽  
Author(s):  
Philippe Bonniaud ◽  
Aurélie Fabre ◽  
Nelly Frossard ◽  
Christophe Guignabert ◽  
Mark Inman ◽  
...  
Keyword(s):  
Experimental Research ◽  
Task Force ◽  
Ex Vivo ◽  
Experimental Models ◽  
Chronic Obstructive ◽  
Ethical Perspective ◽  
Validity Of Results ◽  
Use Of Resources ◽  
Research Recommendations

Experimental models are critical for the understanding of lung health and disease and are indispensable for drug development. However, the pathogenetic and clinical relevance of the models is often unclear. Further, the use of animals in biomedical research is controversial from an ethical perspective.The objective of this task force was to issue a statement with research recommendations about lung disease models by facilitating in-depth discussions between respiratory scientists, and to provide an overview of the literature on the available models. Focus was put on their specific benefits and limitations. This will result in more efficient use of resources and greater reduction in the numbers of animals employed, thereby enhancing the ethical standards and translational capacity of experimental research.The task force statement addresses general issues of experimental research (ethics, species, sex, age,ex vivoandin vitromodels, gene editing). The statement also includes research recommendations on modelling asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, lung infections, acute lung injury and pulmonary hypertension.The task force stressed the importance of using multiple models to strengthen validity of results, the need to increase the availability of human tissues and the importance of standard operating procedures and data quality.

Instability modulation properties of the (2 + 1)-dimensional Kundu–Mukherjee–Naskar model in travelling wave solutions

2021 ◽  
pp. 2150217
Author(s):  
Haci Mehmet Baskonus ◽  
Juan Luis García Guirao ◽  
Ajay Kumar ◽  
Fernando S. Vidal Causanilles ◽  
German Rodriguez Bermudez
Keyword(s):  
Function Method ◽  
Periodic Wave ◽  
Travelling Wave ◽  
Travelling Wave Solutions ◽  
Validity Of Results ◽  
Periodic Wave Solutions ◽  
Wave Solutions

This paper focuses on the instability modulation and new travelling wave solutions of the (2 + 1)-dimensional Kundu–Mukherjee–Naskar equation via the tanh function method. Dark, mixed dark–bright, complex solitons and periodic wave solutions are archived. Strain conditions for the validity of results are also reported. Instability modulation properties of the governing model are also extracted. Various wave simulations in 2D, 3D and contour graphs under the strain conditions are presented.

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