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1

A Framework for Conducting ESL/EFL Construct Validation Studies.  

ERIC Educational Resources Information Center

|The purpose for which a test is used and the examinees' stage of learning are two anchor points that are incorporated into a suggested framework for conducting construct validation studies for tests of students with English as a second language (ESL) or English as a foreign language (EFL). The framework includes the use of generalizability…

Mouw, John T.; Perkins, Kyle

2

The Validity of Graduate Management Admission Test Scores: A Summary of Studies Conducted from 1997 to 2004  

ERIC Educational Resources Information Center

The validity of Graduate Management Admission Test (GMAT) scores is examined by summarizing 273 studies conducted between 1997 and 2004. Each of the studies was conducted through the Validity Study Service of the test sponsor and contained identical variables and statistical methods. Validity coefficients from each of the studies were corrected…

Talento-Miller, Eileen; Rudner, Lawrence M.

2008-01-01

3

Conducting Ecologically Valid Prevention Research: Recruiting and Retaining a “Whole Village” in Multimethod, Multiagent Studies  

Microsoft Academic Search

Many prevention studies are now designed with complementary interventions in different settings. Evaluations of these interventions require assessing the child's behavior in each of these settings. Conducting these studies, therefore, may involve recruiting school districts, principals, classroom teachers, peers, parents, siblings, and in later years, employers and intimate partners. These participants may be considered natural raters or satellite subjects, depending

Deborah M. Capaldi; Patti Chamberlain; Rebecca A. Fetrow; Jane E. Wilson

1997-01-01

4

Global 3-D EM inversion of Sq variations based on simultaneous source and conductivity determination: concept validation and resolution studies  

NASA Astrophysics Data System (ADS)

We present a novel global 3-D electromagnetic (EM) inverse solution that allows to work in a unified and consistent manner with frequency-domain data that originate from ionospheric and magnetospheric sources irrespective of their spatial complexity. The main idea behind the approach is simultaneous determination of the source and conductivity distribution in the Earth. Such a determination is implemented in our solution as a looped sequential procedure that involves two steps: (1) determination of the source using a fixed 3-D conductivity model and (2) recovery of a 3-D conductivity model using a fixed source. We focus in this paper on analysis of Sq data and numerically verify each step separately and combined using data synthesized from 3-D models of the Earth induced by a realistic Sq source. To determine the source we implement an approach that makes use of a known conductivity structure of the Earth with non-uniform oceans. Based on model studies we show that this approach outperforms the conventional potential method. As for recovery of 3-D conductivity in the mantle, our inverse scheme relies on a regularized least-square formulation, exploits a limited-memory quasi-Newton optimization method and makes use of the adjoint source approach to calculate efficiently the misfit gradient. We perform resolution studies with checkerboard conductivity structures at depths between 10 and 1600 km for different inverse setups and conclude from these studies that: (1) inverting Z component gives much better results than inverting all (X, Y and Z) components; (2) data from the Sq source allows for resolving 3-D structures in depth range between 100 and 520 km; (3) the best resolution is achieved in the depth range of 100-250 km.

Koch, Stephan; Kuvshinov, Alexey

2013-10-01

5

Validities and abilities in criminal profiling: a critique of the studies conducted by Richard Kocsis and his colleagues.  

PubMed

In a recent issue of this journal, Kocsis reviewed the criminal profiling research that he and his colleagues have conducted during the past 4 years. Their research examines the correlates of profile accuracy with respect to the skills of the individual constructing the profile, and it has led Kocsis to draw conclusions that are important to the profiling field. In this article, the authors review the contributions of the Kocsis studies and critique their methodological and conceptual foundations. The authors raise a number of concerns and argue that data from the Kocsis studies fail to support many of the conclusions presented in his recent review. The authors present evidence in support of their assertions and provide recommendations that will allow future research in the area to generate data that are more meaningful and generalizable. PMID:16648388

Bennell, Craig; Jones, Natalie J; Taylor, Paul J; Snook, Brent

2006-06-01

6

Validities and Abilities in Criminal Profiling: A Critique of the Studies Conducted by Richard Kocsis and His Colleagues  

Microsoft Academic Search

In a recent issue of this journal, Kocsis reviewed the criminal profiling research that he and his colleagues have conducted during the past 4 years. Their research examines the correlates of profile accuracy with respect to the skills of the individual constructing the profile, and it has led Kocsis to draw conclusions that are important to the profiling field. In

Craig Bennell; Natalie J. Jones; Paul J. Taylor; Brent Snook

2006-01-01

7

Compatibility Study of Conductive Flooring.  

National Technical Information Service (NTIS)

This report presents the findings of a study performed to assess certain physical properties of four types of conductive flooring-conductive terrazzo, conductive vinyl, conductive rubber, and monolithic trowel-on. The study provides comparative data on wh...

A. Smith

1976-01-01

8

29 CFR 1607.14 - Technical standards for validity studies.  

Code of Federal Regulations, 2010 CFR

...Technical standards for validity studies. 1607.14 Section 1607...Appropriateness of content validity studies. Users choosing to validate...appropriate to conduct such a study in the particular employment...commonsense, judgment, leadership, and spatial ability....

2009-07-01

9

29 CFR 1607.14 - Technical standards for validity studies.  

Code of Federal Regulations, 2010 CFR

...Technical standards for validity studies. 1607.14 Section 1607...Appropriateness of content validity studies. Users choosing to validate...appropriate to conduct such a study in the particular employment...commonsense, judgment, leadership, and spatial ability....

2010-07-01

10

Family History Validation Study  

Cancer.gov

The Family History Validation Study is a methodologic study to assess the completeness and accuracy of self-reports of family history of cancer. A questionnaire was administered by computer-assisted telephone interviewing (CATI) to a probability sample of 1,380 Connecticut residents, ages 25-64 years. The questionnaire asked about the occurrence of cancer in first- and second-degree relatives, except for grandchildren.

11

Conducting Longitudinal Studies  

ERIC Educational Resources Information Center

|Although time and resource intensive, longitudinal studies offer the ability to examine the direction and magnitude of causal relationships that cannot be accomplished through cross-sectional design. (Contains 1 figure.)|

Bauer, Karen W.

2004-01-01

12

Family History Validation Study  

Cancer.gov

The telephone interviews were completed in October, 2001. Validation of cancer reports began in 2002 and was completed in 2005. The analyses will yield estimates of sensitivity and specificity of positive and negative reports of lung, prostate, colorectal, breast, and ovarian cancers in first- and second-degree relatives. Other cancer sites will be evaluated if numbers permit. We will also explore relationships between demographic, psychosocial, and medical factors associated with reporting accuracy.

13

Validation of the Work Observation Method By Activity Timing (WOMBAT) method of conducting time-motion observations in critical care settings: an observational study  

PubMed Central

Background Electronic documentation handling may facilitate information flows in health care settings to support better coordination of care among Health Care Providers (HCPs), but evidence is limited. Methods that accurately depict changes to the workflows of HCPs are needed to assess whether the introduction of a Critical Care clinical Information System (CCIS) to two Intensive Care Units (ICUs) represents a positive step for patient care. To evaluate a previously described method of quantifying amounts of time spent and interruptions encountered by HCPs working in two ICUs. Methods Observers used PDAs running the Work Observation Method By Activity Timing (WOMBAT) software to record the tasks performed by HCPs in advance of the introduction of a Critical Care clinical Information System (CCIS) to quantify amounts of time spent on tasks and interruptions encountered by HCPs in ICUs. Results We report the percentages of time spent on each task category, and the rates of interruptions observed for physicians, nurses, respiratory therapists, and unit clerks. Compared with previously published data from Australian hospital wards, interdisciplinary information sharing and communication in ICUs explain higher proportions of time spent on professional communication and documentation by nurses and physicians, as well as more frequent interruptions which are often followed by professional communication tasks. Conclusions Critical care workloads include requirements for timely information sharing and communication and explain the differences we observed between the two datasets. The data presented here further validate the WOMBAT method, and support plans to compare workflows before and after the introduction of electronic documentation methods in ICUs.

2011-01-01

14

Predictive Validity of Childhood Oppositional Defiant Disorder and Conduct Disorder: Implications for the DSM–V  

Microsoft Academic Search

Data are presented from 3 studies of children and adolescents to evaluate the predictive validity of childhood oppositional defiant disorder (ODD) and conduct disorder (CD) as defined in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM–IV; American Psychiatric Association, 1994) and the International Classification of Diseases, Version 10 (ICD-10; World Health Organization, 1992). The present analyses strongly

Jeffrey D. Burke; Irwin Waldman; Benjamin B. Lahey

2010-01-01

15

Neurophysiology of Nerve Conduction Studies  

Microsoft Academic Search

The methodology for performing standard nerve conduction studies has been established by identifying the most helpful and\\u000a consistent physiological data obtainable while being constrained by a variety of technical and practical limitations. Nerve\\u000a stimulation occurs underneath the negatively charged anode of the applied stimulator and simultaneous hyperpolarization of\\u000a the nerve occurs beneath the positively charged cathode. Referential or bipolar recording

James B. Caress; Gregory J. Esper; Seward B. Rutkove

16

Nerve conduction and electromyography studies.  

PubMed

Nerve conduction studies (NCS) and electromyography (EMG), often shortened to 'EMGs', are a useful adjunct to clinical examination of the peripheral nervous system and striated skeletal muscle. NCS provide an efficient and rapid method of quantifying nerve conduction velocity (CV) and the amplitude of both sensory nerve action potentials (SNAPs) and compound motor action potentials (cMAPs). The CV reflects speed of propagation of action potentials, by saltatory conduction, along large myelinated axons in a peripheral nerve. The amplitude of SNAPs is in part determined by the number of axons in a sensory nerve, whilst amplitude of cMAPs reflects integrated function of the motor axons, neuromuscular junction and striated muscle. Repetitive nerve stimulation (RNS) can identify defects of neuromuscular junction (NMJ) transmission, pre- or post-synaptic. Needle EMG examination can detect myopathic changes in muscle and signs of denervation. Combinations of these procedures can establish if motor and/or sensory nerve cell bodies or peripheral nerves are damaged (e.g. motor neuronopathy, sensory ganglionopathy or neuropathy), and also indicate if the primary target is the axon or the myelin sheath (i.e. axonal or demyelinating neuropathies). The distribution of nerve damage can be determined as either generalised, multifocal (mononeuropathy multiplex) or focal. The latter often due to compression at the common entrapment sites (such as the carpal tunnel, Guyon's canal, cubital tunnel, radial groove, fibular head and tarsal tunnel, to name but a few of the reported hundred or so 'entrapment neuropathies'). PMID:22614870

Kane, N M; Oware, A

2012-05-22

17

41 CFR 60-3.14 - Technical standards for validity studies.  

Code of Federal Regulations, 2010 CFR

...Technical standards for validity studies. 60-3.14 Section 60-3...Appropriateness of content validity studies. Users choosing to validate...appropriate to conduct such a study in the particular employment...commonsense, judgment, leadership, and spatial ability....

2010-07-01

18

41 CFR 60-3.14 - Technical standards for validity studies.  

Code of Federal Regulations, 2010 CFR

...Technical standards for validity studies. 60-3.14 Section 60-3...Appropriateness of content validity studies. Users choosing to validate...appropriate to conduct such a study in the particular employment...commonsense, judgment, leadership, and spatial ability....

2009-07-01

19

41 CFR 60-3.14 - Technical standards for validity studies.  

Code of Federal Regulations, 2010 CFR

...Technical standards for validity studies. 60-3.14 Section 60-3...Appropriateness of content validity studies. Users choosing to validate...appropriate to conduct such a study in the particular employment...commonsense, judgment, leadership, and spatial ability....

2008-07-01

20

NOAA's hydrolab conducts reef studies  

NASA Astrophysics Data System (ADS)

This summer, scuba-diving scientists operating from Hydrolab, NOAA's undersea laboratory, are carrying out four experiments aimed at producing better management of coral reefs and their fishery resources. Hydrolab is located at a depth of 50 feet, near the mouth of the Salt River, off St. Croix, U.S. Virgin Islands. The lab houses four scientists for up to 2 weeks at a time, permitting them to swim out into the water to conduct research. The projects make use of both the natural coral reef near Hydrolab and the nearby artificial reef constructed for comparison studies.

21

VALIDATION OF A THERMAL CONDUCTIVITY MEASUREMENT SYSTEM FOR FUEL COMPACTS  

SciTech Connect

A high temperature guarded-comparative-longitudinal heat flow measurement system has been built to measure the thermal conductivity of a composite nuclear fuel compact. It is a steady-state measurement device designed to operate over a temperature range of 300 K to 1200 K. No existing apparatus is currently available for obtaining the thermal conductivity of the composite fuel in a non-destructive manner due to the compact’s unique geometry and composite nature. The current system design has been adapted from ASTM E 1225. As a way to simplify the design and operation of the system, it uses a unique radiative heat sink to conduct heat away from the sample column. A finite element analysis was performed on the measurement system to analyze the associated error for various operating conditions. Optimal operational conditions have been discovered through this analysis and results are presented. Several materials have been measured by the system and results are presented for stainless steel 304, inconel 625, and 99.95% pure iron covering a range of thermal conductivities of 10 W/m*K to 70 W/m*K. A comparison of the results has been made to data from existing literature.

Jeff Phillips; Colby Jensen; Changhu Xing; Heng Ban

2011-03-01

22

Reliability, validity, and factor structure of the Swedish Youth Psychopathic Trait Inventory in a UK sample of conduct disordered boys  

Microsoft Academic Search

The Swedish Youth Psychopathy Traits Inventory (YPI) is a newly developed self-report measure of psychopathy. Currently, there are no studies looking at the reliability, validity, and factor structure of this measure in conduct disordered adolescents in the UK. A sample of 115 male adolescents (mean age 16.22) with a range of conduct problems on the Kiddie Schedule for Affective Disorders

Mairead C. Dolan; Charlotte E. Rennie

2006-01-01

23

Critical validation studies of neurofeedback.  

PubMed

The field of neurofeedback training has proceeded largely without validation. In this article the authors review studies directed at validating sensory motor rhythm, beta and alpha-theta protocols for improving attention, memory, and music performance in healthy participants. Importantly, benefits were demonstrable with cognitive and neurophysiologic measures that were predicted on the basis of regression models of learning to enhance sensory motor rhythm and beta activity. The first evidence of operant control over the alpha-theta ratio is provided, together with remarkable improvements in artistic aspects of music performance equivalent to two class grades in conservatory students. These are initial steps in providing a much needed scientific basis to neurofeedback. PMID:15564053

Gruzelier, John; Egner, Tobias

2005-01-01

24

Challenges in conducting psychiatry studies in India  

PubMed Central

A large number of psychiatry studies are conducted in India. Psychiatry studies are complex and present unique challenges in the Indian setting. Ethical issues pertaining to the risk of worsening of illness, use of placebo and validity of informed consents are commonly faced. Site selection can be difficult due to the relative paucity of ICH-GCP (International Conference on Harmonisation - Good Clinical Practice) trained psychiatry investigators in India. Recruitment can be challenging due to issues such as strict eligibility criteria, (lack of) availability of caregiver, illness-related considerations, etc. Assessment of the consent capacity of patients is not simple, while structured assessments are not commonly employed. As the illness fluctuates, the consent capacity may change, thus requiring continued assessment of consent capacity. Study patients run the risk of worsening of illness and suicide due to exposure to inactive treatments; this risk is counterbalanced by use of appropriate study designs, as well as the indirect psychotherapeutic support received. Psychiatry studies are associated with a high placebo response. This necessitates conduct of placebo-controlled studies despite the attendant difficulties. Also, the high placebo response is often the cause of failed trials. Rating scales are essential for assessment of drug response. Some rating instruments as well as some rater training procedures may not be suitable for the Indian setting. Technological advancements may increase the procedural complexity but improve the quality of ratings. Psychiatry studies present monitors and auditors with unique scenarios too. Utilization of psychiatry specific training and expertise is recommended to ensure successful conduct of these studies in India.

Kharawala, Saifuddin; Dalal, Jeroze

2011-01-01

25

CANFOR Portuguese version: validation study  

PubMed Central

Background The increase in prisoner population is a troublesome reality in several regions of the world. Along with this growth there is increasing evidence that prisoners have a higher proportion of mental illnesses and suicide than the general population. In order to implement strategies that address criminal recidivism and the health and social status of prisoners, particularly in mental disordered offenders, it is necessary to assess their care needs in a comprehensive, but individual perspective. This assessment must include potential harmful areas like comorbid personality disorder, substance misuse and offending behaviours. The Camberwell Assessment of Need – Forensic Version (CANFOR) has proved to be a reliable tool designed to accomplish such aims. The present study aimed to validate the CANFOR Portuguese version. Methods The translation, adaptation to the Portuguese context, back-translation and revision followed the usual procedures. The sample comprised all detainees receiving psychiatric care in four forensic facilities, over a one year period. A total of 143 subjects, and respective case manager, were selected. The forensic facilities were chosen by convenience: one prison hospital psychiatric ward (n=68; 47.6%), one male (n=24; 16.8%) and one female (n=22; 15.4%) psychiatric clinic and one civil security ward (n=29; 20.3%), all located nearby Lisbon. Basic descriptive statistics and Kappa weighted coefficients were calculated for the inter-rater and the test-retest reliability studies. The convergent validity was evaluated using the Global Assessment of Functioning and the Brief Psychiatric Rating Scale scores. Results The majority of the participants were male and single, with short school attendance, and accused of a crime involving violence against persons. The most frequent diagnosis was major depression (56.1%) and almost half presented positive suicide risk. The reliability study showed average Kappa weighted coefficients of 0.884 and 0.445 for inter-rater and test-retest agreement, respectively. The convergent validity study presented highly significant correlations between unmet needs scores, GAF and BPRS scores. Conclusions The CANFOR Portuguese version revealed similar psychometric properties to the original English version. Moreover, the results of the reliability and validity studies indicate that the tool is appropriate for individual care needs assessment and as a guide for the mental health and social interventions in forensic psychiatric services.

2013-01-01

26

Joint Adaptive Communications System (JACS) Concept Validation Study.  

National Technical Information Service (NTIS)

The Concept Validation Study of Joint Adaptive Communication System (JACS), conducted by David Sarnoff Research Center (Sarnoff) under contract to Air Force, focused on evaluation of network algorithms for a self-organizing, self-routing, self-maintaining...

N. P. Newman T. Stiller W. E. Stephens

1997-01-01

27

HIPAA's Preconsent: Impact on Study Validity.  

PubMed

The Health Insurance Portability and Accountability Act (HIPAA) regulations added potential validity threats to clinical studies. The HIPAA regulations, using the principle of patient autonomy were designed to increase patient's control over the all health related information. The Department of Health and Human Services did not identify rules related to research regulations believing HIPAA regulations facilitate investigations through use of de-identified information. Yet, under HIPAA guidelines, health care agencies can not allow access because of the need to obtain a patient's prior permission to release raw data. The problem of how to conduct investigations in the face of the HIPAA "Privacy Rule" raises concerns for effects on subject recruitment and selection. This paper examines the impact of obtaining a HIPAA preconsent on subject recruitment, selection, and subject characteristics, and offers strategies for addressing the validity threats associated with the HIPAA regulations. J Am Psychiatr Nurses Assoc, 2008; 14(3), 225-230. DOI: 10.1177/1078390308319224. PMID:21665768

Rice, Michael J; Records, Kathie

2008-06-01

28

Assessing the Risk of Domestic Violence Reoffending: A Validation Study  

Microsoft Academic Search

Little research has been conducted to validate available instruments for assessing the risk of domestic violence reoffending, especially research using some form of prospective design. This study uses a prospective design to determine the reliability and validity of the Domestic Violence Screening Instrument (DVSI). The analysis is based on a sample of 1,465 male domestic violence offenders selected consecutively over

Kirk R. Williams; Amy Barry Houghton

2004-01-01

29

CFD Validation Studies for Hypersonic Flow Prediction.  

National Technical Information Service (NTIS)

A series of experiments to measure pressure and heating for code validation involving hypersonic, laminar, separated flows was conducted at the Calspan-University at Buffalo Research Center (CUBRC) in the Large Energy National Shock (LENS) tunnel. The exp...

P. A. Gnoffo

2001-01-01

30

CFD Validation Studies for Hypersonic Flow Prediction  

Microsoft Academic Search

A series of experiments to measure pressure and heating for code validation involving hypersonic, laminar, separated flows was conducted at the Calspan-University at Buffalo Research Center (CUBRC) in the Large Energy National Shock (LENS) tunnel. The experimental data serve as a focus for a code validation session but are not available to the authors until the conclusion of this session.

Peter A. Gnoffo

2001-01-01

31

49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?  

Code of Federal Regulations, 2011 CFR

...and are laboratories required to conduct it? 40.89 Section 40.89 Transportation...and are laboratories required to conduct it? (a) Specimen validity testing is the evaluation of the specimen to determine if it is consistent with normal human...

2011-10-01

32

Nuts and bolts of conducting feasibility studies.  

PubMed

Many factors can affect the successful implementation and validity of intervention studies. A primary purpose of feasibility and pilot studies is to assess the potential for successful implementation of the proposed main intervention studies and to reduce threats to the validity of these studies. This article describes a typology to guide the aims of feasibility and pilot studies designed to support the development of randomized controlled trials and provides an example of the studies underlying the development of one rehabilitation trial. The purpose of most feasibility and pilot studies should be to describe information and evidence related to the successful implementation and validity of a planned main trial. Null hypothesis significance testing is not appropriate for these studies unless the sample size is properly powered. The primary tests of the intervention effectiveness hypotheses should occur in the main study, not in the studies that are serving as feasibility or pilot studies. PMID:23433271

Tickle-Degnen, Linda

33

Validation of Chymes: simulant studies  

Microsoft Academic Search

The CFD code Chymes models the initial mixing between core material and water in the lower plenum of a PWR. This paper reviews experiments to validate the code being carried out by Nuclear Electric and Oxford University. These experiments use isothermal and hot simulant fluids and particles in a thich-tank geometry to aid flow visualisation. Comparison with Chymes calculations (made

R. W. Hall; D. F. Fletcher

1995-01-01

34

An experimentally validated thermo-mechanical model for the prediction of thermal contact conductance  

Microsoft Academic Search

A predictive model for estimating thermal contact conductance between two nominally flat metallic rough surfaces has been developed and experimentally validated. The predictive model consists of two complementary parts, the first of which is a surface deformation analysis to calculate the actual area of contact for each contact spot, while the second accounts for the effects of constriction resistance and

Vishal Singhal; Paul J. Litke; Anthony F. Black; Suresh V. Garimella

2005-01-01

35

Predicting children’s academic achievement from early assessment scores: a validity generalization study  

Microsoft Academic Search

Although there have been numerous studies investigating the predictive validity of early assessment, observed predictive validity coefficients across studies are not stable. A validity generalization study was conducted in order to answer the question of whether the relationship between early assessment of children and later achievement is generalizable or situation-specific. This study examined 716 predictive correlation coefficients from 44 studies

Juhu Kim; Hoi K Suen

2003-01-01

36

in children. Its results were drawn with limited sample size obtained after a short phase of data collection. A further study should be conducted to get more precise and valid results that may be useful for preventing UTI among children.  

PubMed

This hospital-based case-control study was conducted from September 1998 to January 1999 in Metro Manila, Philippines. General objective of the study is to determine the association between selected hygiene behavior and urinary tract infection (UTI) among children aged 6-12 years. Specifically, the study is designed to examine the relationship between UTI and urination, defecation, washing and bathing habits. Twenty-three cases of children with UTI and an equal number of controls were recruited in four tertiary hospitals. The study association was determined by using odds ratio, the chi-square test and the Fisher exact test, where appropriate, in simple analysis. Furthermore, exact logistic regression analysis was applied to overcome the problem of small sample size. The data suggested that bathing habit less than daily, holding of urination during daytime, and washing habit after defecation might have risk effects on UTI. There was not enough evidence of significant association between UTI and other study exposures. Among extraneous variables, age group or school enrollment of children had a borderline significant association with UTI after adjusted simultaneously for selected variables. This study served as a pilot of the Preventive Nephrology Project (Department of Health, Philippines) in determining selected risk factors of PMID:11414449

Hoi, L V; Sarol, J N; Uriarte, R D; Tadoy, S A

2000-01-01

37

DC electrical conductivity study of cerium doped conducting glass systems  

NASA Astrophysics Data System (ADS)

The glass samples of composition 60V2O5-5P2O5-(35-x)B2O3-xCeO2, (1 <= x <= 5) were prepared by the conventional melt quench method. The samples were characterized by X-ray diffraction and thermo gravimetric-differential thermal analysis. The glass transition temperature and crystallization temperature determined from TG-DTA analysis. The DC electrical conductivity has been carried out in the temperature range 303-473 K. The maximum conductivity and minimum activation energy were found to be 0.039 Scm-1 and 0.15 eV at 473 K for x=1, respectively.

Barde, R. V.; Waghuley, S. A.

2013-06-01

38

Validation of Structure Metrics: A Case Study.  

National Technical Information Service (NTIS)

The paper presents a framework for the validation of axiomatic structure metrics. In a case study, the comprehensibility of type-expressions in the functional programming language Miranda has been investigated. A structure metric for the comprehensibility...

K. G. van den Berg P. M. van der Broek G. M. van Petersen

1992-01-01

39

A Validation Study of Maslow's Hierarchy of Needs Theory.  

ERIC Educational Resources Information Center

|A study was conducted to expand the body of research that tests the validity of Abraham Maslow's hierarchy of needs theory in a work context where it often serves as a guide for the supervisor's relationships with his subordinates. Data was gathered by questionnaire which tested for a hierarchy of needs among instructors at four community…

Clay, Rex J.

40

Predictive Validity Study of the APS Reading Test.  

ERIC Educational Resources Information Center

In July 1994, College of the Canyons (COC) in California conducted several predictive validity studies of the College Board Assessment and Placement Services (APS) Reading Test. COC began using the 35-question objective format test in spring 1993. Fall 1993 test scores were used in determining the ability of the APS Reading Test to predict student…

College of the Canyons, Santa Clarita, CA.

41

Homework Purpose Scale for High School Students: A Validation Study  

ERIC Educational Resources Information Center

The purpose of this study is to test the validity of scores on the Homework Purpose Scale using 681 rural and 306 urban high school students. First, confirmatory factor analysis was conducted on the rural sample. The results reveal that the Homework Purpose Scale comprises three separate yet related factors, including Learning-Oriented Reasons,…

Xu, Jianzhong

2010-01-01

42

Severity prediction rules in community acquired pneumonia: a validation study  

Microsoft Academic Search

BACKGROUNDThe British Thoracic Society (BTS) developed a rule (BTSr) based on severity criteria to predict short term mortality in adults admitted to hospital with community acquired pneumonia (CAP). However, neither the BTSr nor a recent modification of it (mBTSr) have been validated in the UK. A case-control study was conducted in a typical UK population to determine the clinical factors

W S Lim; S Lewis; J T Macfarlane

2000-01-01

43

FETAX interlaboratory validation study: Phase 2 testing  

SciTech Connect

The Frog Embryo Teratogenesis Assay-Xenopus (FETAX) is a 96-h whole embryo developmental toxicity screening assay that can be used in ecotoxicology and in detecting mammalian developmental toxicants when an in vitro metabolic activation system is employed. A standardized American Society for Testing and Materials (ASTM) guide for the conduct of FETAX has been published along with a companion atlas that helps in embryo staging and identifying malformations. As part of the ASTM process, an interlaboratory validation study was undertaken to evaluate the repeatability and reliability of FETAX. Six different laboratories participated in the study. Each laboratory utilized one technician with the exception of one laboratory, which utilized two independent technicians. In Phase 1, FETAX proved to be more repeatable and reliable than many other bioassays. However, some excessive variation was observed in a few laboratories. Some of this variation may have been due to an initial lack of experience with the assay by some technicians. Phase 2, which is reported here, showed far less intralaboratory and interlaboratory variability than did Phase 1. Nonteratogens such as saccharin and sodium cyclamate showed the most consistent results, whereas more variability was observed for the teratogens caffeine and 5-fluorouracil. Interlaboratory coefficient of variation values for all FETAX end points ranged from 7.3 to 54.7%. The minimum concentration to inhibit growth proved to be the most variable end point for three of the four test chemicals, whereas the LC50 and EC50 (malformation) proved to be less variable.

Bantle, J.A. (Oklahoma State Univ., Stillwater, OK (United States). Dept. of Zoology); Burton, D.T. (WYE Research and Educational Center, Queenstown, MD (United States)); Dawson, D.A. (Ashland Univ., OH (United States). Dept. of Biology and Toxicology) (and others)

1994-10-01

44

Proton Conductivity Studies on Biopolymer Electrolytes  

NASA Astrophysics Data System (ADS)

Proton conducting solid biopolymer electrolyte membranes consisting of methyl cellulose (MC) and different wt.% of ammonium nitrate (NH4NO3) were prepared by solution cast technique. Impedance spectroscopy was carried out to study electrical characteristics of bulk materials. The ionic conductivity of the prepared samples was calculated using the bulk resistance (Rb) obtained from impedance spectroscopy plot. The highest ionic conductivity obtained was 1.17×10-4 Scm-1 for the sample with composition ratio of MC(50): NH4NO3(50). To enhance the ionic conductivity, propylene carbonate (PC) and ethylene carbonate (EC) plasticizers were introduced. It was found that the ionic conductivity of polymer electrolyte membranes increased with the increase in plasticizers concentration. The ionic conductivities of solid polymer electrolytes based on MC-NH4NO3-PC was enhanced up to 4.91×10-3 Scm-1 while for the MC-NH4NO3-EC system, the highest conductivity was 1.74×10-2 Scm-1. The addition of more plasticizer however decreases in mechanical stability of the membranes.

Harun, N. I.; Sabri, N. S.; Rosli, N. H. A.; Taib, M. F. M.; Saaid, S. I. Y.; Kudin, T. I. T.; Ali, A. M. M.; Yahya, M. Z. A.

2010-07-01

45

Proton Conductivity Studies on Biopolymer Electrolytes  

SciTech Connect

Proton conducting solid biopolymer electrolyte membranes consisting of methyl cellulose (MC) and different wt.% of ammonium nitrate (NH{sub 4}NO{sub 3}) were prepared by solution cast technique. Impedance spectroscopy was carried out to study electrical characteristics of bulk materials. The ionic conductivity of the prepared samples was calculated using the bulk resistance (R{sub b}) obtained from impedance spectroscopy plot. The highest ionic conductivity obtained was 1.17x10{sup -4} Scm{sup -1} for the sample with composition ratio of MC(50): NH{sub 4}NO{sub 3}(50). To enhance the ionic conductivity, propylene carbonate (PC) and ethylene carbonate (EC) plasticizers were introduced. It was found that the ionic conductivity of polymer electrolyte membranes increased with the increase in plasticizers concentration. The ionic conductivities of solid polymer electrolytes based on MC-NH{sub 4}NO{sub 3}-PC was enhanced up to 4.91x10{sup -3} Scm{sup -1} while for the MC-NH{sub 4}NO{sub 3}-EC system, the highest conductivity was 1.74x10{sup -2} Scm{sup -1}. The addition of more plasticizer however decreases in mechanical stability of the membranes.

Harun, N. I.; Sabri, N. S.; Rosli, N. H. A.; Taib, M. F. M.; Saaid, S. I. Y.; Kudin, T. I. T. [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Ali, A. M. M.; Yahya, M. Z. A. [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Institute of Science, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia)

2010-07-07

46

Design and conduct of epidemiologic studies.  

PubMed

This article reviews the advantages and disadvantages of the experimental vis-a-vis the nonexperimental (observational) epidemiologic approach in the assessment of causal relationships. Nonexperimental epidemiologic strategies, including the study of ecologic correlations, concurrent and nonconcurrent prospective designs, as well as case-control and cross-sectional designs, are briefly discussed. Among the case-control designs, reference is made to matched and to "nested" case-control studies. These different design approaches are discussed in relation to issues of external validity, bias, confounding, interaction, and precision. PMID:3495793

Szklo, M

1987-03-01

47

Critical validation studies of neurofeedback  

Microsoft Academic Search

In the pediatric field, the most widespread application of electroencephalo- graphic (EEG) biofeedback (neurofeedback) is for the treatment of attention deficit hyperactivity disorder (ADHD). Work began with the pioneering studies of Lubar et al (1-3) with the hypothesis that voluntary production of the sensory motor rhythm (SMR) required a child to stabilize or suppress motor activity while remaining attentive. The

John Gruzelier; Tobias Egner

2005-01-01

48

Conductivity study of chitosan based nanocomposites  

NASA Astrophysics Data System (ADS)

Bio polymer like chitosan is dissolved in acids like formic and acetic acid and CdS nano particle prepared by chemical methods has been embedded in the salts of chitosan matrix. The viscous solution is cast into film on the glass substrate using spin coating method and their ionic conductivity has been studied for various frequencies and temperatures.

Mohan, C. Raja; Murugan, S.; Jayakumar, K.

2012-06-01

49

Intercostal nerve conduction study in man  

Microsoft Academic Search

A new surface technique for the conduction study of the lower intercostal nerves has been developed and applied to 30 normal subjects. The problem of the short available nerve segment of the intercostal nerves and the bizzare compound motor action potential (CMAP) of inconsistent latency while recording over the intercostal muscles, is overcome by applying recording electrodes over the rectus

S Pradhan; A Taly

1989-01-01

50

Studying pretrial publicity effects: new methods for improving ecological validity and testing external validity.  

PubMed

Although research examining the effects of pretrial publicity (PTP) on individuals' appraisals of a defendant and verdict decision making generally has been found to be internally valid, the external validity has been questioned by some social scientists as well as lawyers and judges. It is often proposed that the verisimilitude (or ecological validity) ofthe research should be increased in the service of increasing external validity; however, increasing verisimilitude can be costly in terms of both time and money. It is proposed that the Internet is a viable means of conducting PTP research that allows high verisimilitude without high costs. This is demonstrated with a study in which we used the Internet to examine PTP effects in an actual trial as it was taking place. Successful use of the Internet to conduct experimental research in other areas of psychology and law is discussed, as well as the importance of future research examining whether independent variables interact with methods in ways that undermine the generalizability of research findings. PMID:11868618

Studebaker, Christina A; Robbennolt, Jennifer K; Penrod, Steven D; Pathak-Sharma, Maithilee K; Groscup, Jennifer L; Devenport, Jennifer L

2002-02-01

51

40 CFR 761.392 - Preparing validation study samples.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Preparing validation study samples. 761.392 Section 761.392...COMMERCE, AND USE PROHIBITIONS Comparison Study for Validating a New Performance-Based... § 761.392 Preparing validation study samples. (a)(1) To...

2013-07-01

52

Validation Studies of the Physical Activity Scale  

Cancer.gov

Validation Studies of the Physical Activity Scale Aadahl et al. 2007 See reference #74 Methods Relation between self-reported physical activity level and VO2max (l/min) using linear regression analyses with covariates sex, age and bodyweight Sample 57

53

Intercostal nerve conduction study in man.  

PubMed

A new surface technique for the conduction study of the lower intercostal nerves has been developed and applied to 30 normal subjects. The problem of the short available nerve segment of the intercostal nerves and the bizzare compound motor action potential (CMAP) of inconsistent latency while recording over the intercostal muscles, is overcome by applying recording electrodes over the rectus abdominis muscle and stimulating the nerves at two points at a fair distance away. With the use of multiple recording sites over the rectus abdominis, the motor points for different intercostal nerves were delineated. CMAP of reproducible latencies and waveforms with sharp take-off points were obtained. Conduction velocity of the intercostal nerves could be determined. PMID:2526200

Pradhan, S; Taly, A

1989-06-01

54

Intercostal nerve conduction study in man.  

PubMed Central

A new surface technique for the conduction study of the lower intercostal nerves has been developed and applied to 30 normal subjects. The problem of the short available nerve segment of the intercostal nerves and the bizzare compound motor action potential (CMAP) of inconsistent latency while recording over the intercostal muscles, is overcome by applying recording electrodes over the rectus abdominis muscle and stimulating the nerves at two points at a fair distance away. With the use of multiple recording sites over the rectus abdominis, the motor points for different intercostal nerves were delineated. CMAP of reproducible latencies and waveforms with sharp take-off points were obtained. Conduction velocity of the intercostal nerves could be determined.

Pradhan, S; Taly, A

1989-01-01

55

Steady-State Hydraulic Tomography in a Laboratory Aquifer with Deterministic Heterogeneity: Multiscale Validation of Hydraulic Conductivity Tomograms  

Microsoft Academic Search

Hydraulic tomography is a technology that facilitates subsurface imaging of hydraulic heterogeneity through the inversion of multiple pumping test data. To date, a comprehensive validation of the hydraulic tomography has not been done either at the laboratory or field scales. Validation of hydraulic conductivity tomograms is possible using synthetic simulations because the forcing functions (initial and boundary conditions; source\\/sink terms)

W. A. Illman; X. Liu; A. J. Craig

2005-01-01

56

49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?  

Code of Federal Regulations, 2012 CFR

...40.89 What is validity testing, and are laboratories required... (a) Specimen validity testing is the evaluation of the specimen...it is consistent with normal human urine. The purpose of validity testing is to determine whether...

2012-10-01

57

Validation Studies of the Arab Teens Lifestyle Study (ATLS)  

Cancer.gov

Validation Studies of the Arab Teens Lifestyle Study (ATLS) Al-Hazzaa et al. 2011 See reference #116 Methods Relation between The Arab Teens Lifestyle Study (ATLS) physical activity questionnaire time spent (min/week) on various physical activity, and

58

HREELS and Auger studies of conducting polymers  

SciTech Connect

High Resolution Electron Energy Loss Spectroscopy (HREELS) and Auger Spectroscopy have been used to examine the surface of conducting polymer samples. The samples were 100 nm thick films of polypyrrole doped with either BF/sub 4/ or ClO/sub 4/ negative ions. The films were made in Sweden and shipped to the USA for study. HREELS spectra could be obtained without difficulty in the samples' as is condition. These spectra showed broad bands corresponding to known polypyrrole vibrational modes. Exposure of the polymer to oxygen had no effect, but water could be adsorbed on the samples at 130 K. In addition to vibrational excitations, broader electronic transitions were also identified. Auger studies were performed in an effort to characterize the surface. These studies indicate that considerable non-stoichiometry exists in the surface region. There were, as expected, problems due to questionable sample cleanliness, sample charging, and electron beam damage. 21 references, 6 figures, 3 tables.

Jennings, W.D.; Chottiner, G.S.; Natarajan, C.; Melo, A.V.; Hoffman, R.W.; O'Grady, W.E.; Lundstrom, I.; Salaneck, W.R.

1984-08-01

59

AMTAS: automated method for testing auditory sensitivity: validation studies.  

PubMed

Three studies are reported assessing the validity of AMTAS, an automated method for obtaining an audiogram, including air- and bone-conduction thresholds (stimuli delivered by a forehead-placed transducer) with masking noise presented to the non-test ear. In Study 1, six subjects at each of three sites were tested using manual audiometry by two audiologists at each site. The mean differences between the audiograms for the paired audiologists provided a measure of the reliability of traditional audiometry. In Study 2, thirty subjects (5 normal hearing, 25 hearing impaired) were tested using AMTAS and manual audiometry. For air-conduction thresholds, AMTAS-manual differences were similar to inter-tester differences in Study 1, but for bone-conduction thresholds, the former were larger. Two possible sources of the greater differences were identified, (1) incorrect reference-equivalent threshold force levels for forehead bone conduction, and (2) a differential effect of middle-ear disease on forehead and mastoid bone-conduction thresholds. In Study 3, intersubject variability was studied for forehead and mastoid bone-conduction thresholds. The results indicate similar variability for the two placement sites. PMID:20109081

Margolis, Robert H; Glasberg, Brian R; Creeke, Sarah; Moore, Brian C J

2010-03-01

60

Evaluating the Construct Validity of Psychopathy in Black and White Male Inmates: Three Preliminary Studies  

Microsoft Academic Search

Although Black inmates represent almost half the population of United States prisons and have been included in several studies of psychopathy, there appear to be no published studies to date addressing the validity of the psychopathy construct in Black inmates. Three studies were conducted to assess the validity of the construct in Black male inmates using Hare's Psychopathy Checklist (PCL).

David S. Kosson; Stevens S. Smith; Joseph P. Newman

1990-01-01

61

Conductivity  

NSDL National Science Digital Library

Students make a simple conductivity tester using a battery and light bulb. They learn the difference between conductors and insulators of electrical energy as they test a variety of materials for their ability to conduct electricity.

Integrated Teaching And Learning Program

62

Statistical power in criterion-related validation studies  

Microsoft Academic Search

Examined systematically the sample sizes necessary to provide adequate power in validation studies under various conditions of range restriction and criterion unreliability. For purposes of brevity, the examination was restricted to the validity parameter values (i.e., true validities) of .35 and .50. Results demonstrate that sample sizes required to produce adequate power in empirical validation studies are substantially larger than

Frank L. Schmidt; John E. Hunter; Vern W. Urry

1976-01-01

63

Reliable Digit Span: A Systematic Review and Cross-Validation Study  

ERIC Educational Resources Information Center

Reliable Digit Span (RDS) is a heavily researched symptom validity test with a recent literature review yielding more than 20 studies ranging in dates from 1994 to 2011. Unfortunately, limitations within some of the research minimize clinical generalizability. This systematic review and cross-validation study was conducted to address these…

Schroeder, Ryan W.; Twumasi-Ankrah, Philip; Baade, Lyle E.; Marshall, Paul S.

2012-01-01

64

Validation Studies of the Arab Teens Lifestyle Study (ATLS)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

65

GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: CHEMICAL DEHALOGENATION  

EPA Science Inventory

Systematically conducted, well-documented treatability studies are an important component of remedy evaluation and selection under the Superfund program. his manual focuses on chemical dehalogenation treatability studies conducted in support of remedy selection that is conducted ...

66

Study on Electrical Conductivity of Coal.  

National Technical Information Service (NTIS)

One of the engineering techniques in underground coal gasification is the electrical linking of holes drilled into the coal seam. The magnitude of electrical conductivity is one of the factors that will determine whether electrical linking is appropriate....

H. Ohuchi J. Soma T. Isobe

1968-01-01

67

40 CFR 160.130 - Conduct of a study.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Conduct of a study. 160.130 Section 160.130 Protection...PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study shall be conducted in...

2013-07-01

68

40 CFR 792.130 - Conduct of a study.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Conduct of a study. 792.130 Section 792.130 Protection...PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in...

2013-07-01

69

Statistical Study of Thermal Contact Conductance.  

National Technical Information Service (NTIS)

A theoretical analysis of the principles of interfacial thermal conductance between two heated metal surfaces in mutual contact is presented. It was determined that when heat flows from one metal to the other, the flow lines converge toward the actual con...

V. T. Nejat

1972-01-01

70

Ethical Issues in Conducting Migrant Farmworker Studies  

Microsoft Academic Search

Migrant farmworkers should be considered a vulnerable population because they work in a hazardous industry, are often members of an ethnic minority, have known difficulty in accessing health care, and are often of lower socioeconomic status. For these reasons, too, it is extremely important to conduct health-related research with this often-underserved group. However, because migrant farmworkers are vulnerable, investigators must

Sharon P. Cooper; Elizabeth Heitman; Erin E. Fox; Beth Quill; Paula Knudson; Sheila H. Zahm; Nancy MacNaughton; Roberta Ryder

2004-01-01

71

Validation of non-Darcian flow effects in slug tests conducted in fractured rock boreholes  

NASA Astrophysics Data System (ADS)

Agreement between more than one type of hydraulic test increases the confidence in T. Constant head step tests can be used to validate the Darcian flow assumption for slug tests. A method is proposed that validates the two main assumptions in the Hvorslev model.

Quinn, Patryk M.; Parker, Beth L.; Cherry, John A.

2013-04-01

72

Upscaling hydraulic conductivity: theory and examples from geohydrological studies  

Microsoft Academic Search

This paper presents an overview of the theory of upscaling hydraulic conductivity and describes two case studies in which some of this theory has been applied. The representative hydraulic conductivity of a numerical model block (‘block conductivity’ for short) is defined in terms of smaller scale hydraulic conductivities. Also, using elementary examples, some general properties of block conductivities are given.

M. F. P. Bierkens; J. W. J. van der Gaast

1998-01-01

73

40 CFR 761.395 - A validation study.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false A validation study. 761.395 Section 761.395 Protection...COMMERCE, AND USE PROHIBITIONS Comparison Study for Validating a New Performance-Based...d)(4) § 761.395 A validation study. (a) Decontaminate the...

2013-07-01

74

Experimental validation of the nerve conduction velocity selective recording technique using a multi-contact cuff electrode  

Microsoft Academic Search

The earthworm (Lumbricus terrestris) is presented as an in vitro model of a peripheral nerve containing only two fibers each with distinctly different conduction velocities, the median and lateral giant fibers (MGF and LGF). The worm model is used with a multi-contact cuff electrode to validate the spatial–temporal filtering effect of different electrode contact configurations and the effect of applying

K. Yoshida; G. A. M. Kurstjens; K. Hennings

2009-01-01

75

Experimental Validation of Numerical Solutions Using the Explicit Green's Approach to Simulate Transient Heat Conduction in Multilayer Systems  

Microsoft Academic Search

This article presents an experimental validation of numerical solutions using the explicit Green's approach (ExGA) for transient heat conduction in multilayer systems. The ExGA is an efficient recurrence relationship for the temperature in the time domain, based on the Green's matrix, which allows explicit time marching with a larger time step than is required by other methods found in the

C. A. B. Vasconcellos; M. M. Reis; W. J. Mansur; A. Tadeu; N. Simões; I. Simões

2012-01-01

76

Sampling theory methodology applicable to data validation studies  

SciTech Connect

In data validation studies, surveys are conducted to obtain information about the data collection process and the uses of the data. In many cases standard sampling techniques can be used. Two methods, stratified random sampling and cluster sampling, were used for surveys in the Form 4 data validation study. Form 4 is a data collection system on monthly generation and consumption of fuels by electric power plants. A description of those applications is given. Sometimes time and cost constraints make more sophisticated controlled sampling approaches necessary. One such approach using balanced incomplete block designs is described; an appendix surveys the existence results for these designs. Sequential methods which may prove to be more cost effective are discussed, as are sequential approaches to the problem of determining the size of a population. Problems requiring further research are also discussed. Some preliminary results on the problem of stratification with respect to more than one variable are included. The results were obtained for the Form 4 respondent population. The Form 4 study indicated that standard statistical sampling methods could be useful in data validation surveys. For example, at least 30 percent of the respondents do not report net generation as the instructions define it, and only 25 percent of the state regulatory agencies use the Form 4 data. Such inferences were possible only because statistical sampling procedures were used. 3 tables.

Chernick, M.R.

1980-01-01

77

Aspects of data validation in acid deposition studies  

SciTech Connect

The recognition of acid deposition as a potentially serious environmental concern has led to extensive research activity. The possible inaccuracies in determination of the chemical composition of collected samples has been the subject of some concern, because relatively low ion concentration levels are typically encountered in samples with low ionic strengths. The evaluation and validation of such chemical data have therefore come to occupy a priority position in acid deposition studies. The intent of these efforts is to direct attention to the overall quality of chemical analysis data. Sampling, sample contamination and several other factors ultimately influence results, however these factors should be a part of the overall quality assurance program. The latter effects are not considered here. Full realization of data validation can be accomplished when the following objectives have been met. Specific considerations include evaluation of measured sample acidity, strong acidity, weak acidity and an acidity calculated from ionic composition data. Determined ionic composition of samples is evaluated from a calculated acidity, an ion balance ratio and from a measured/calculated conductivity ratio. Other considerations, such as a chloride/sodium ratio in marine environments, which may be unique to geographical regions, can also be used. During the period from July 1977 to October 1981 the National Aeronautics and Space Administration supported studies at the Kennedy Space Center, Florida which were designed to evaluate potential environmental effects associated with launch of the space shuttle. The program developed for evaluation and validation of measured acid deposition composition data is presented.

Madsen, B.C.

1983-01-01

78

Validation study of two continuum granular frictional flow theories  

SciTech Connect

Granular kinetic theories are valid in both kinetic (dilute) flow regime and dense collisional (intermediate) flow regime. This is true as long as contacts between two colliding particles are instantaneous. Empirical theories derived from soil mechanics have been traditionally used in continuum modeling for dense granular flows dominated by enduring contact between particles. This study focuses on validating two continuum theories commonly used to model dense frictional granular flows. The first validation example is conducted for a granular bin discharge, and model predictions are compared with a well-known empirical correlation for the discharge rate. The second example involves a more detailed comparison of flow variables with predictions obtained using a discrete technique for granular flow in a simple shear cell. The frictional flow theory that is only activated at the quasi-static flow regime above maximum packing does not show accurate predictions. Better predictions are obtained using a frictional theory that extends in the intermediate flow regime below packing where both collisional and enduring contact between particles occur.

Benyahai, S.

2008-01-01

79

Validating and Calibrating Agent-based Models: a Case Study  

Microsoft Academic Search

In this paper we deal with the validation of an agent-based model and, in particular, with the technical validation process, that is to say all the set of test and methods used to analyze if the results of a simulation agree with reality. Today, thanks to some important studies, validation techniques are more and more complete and reliable: many distributional

Pasquale Cirillo; Carlo Bianchi; Mauro Gallegati; Pietro Vagliasindi

2006-01-01

80

Conducting an Operators' Training and Certification Study  

Microsoft Academic Search

A study of Arizona's water system operator certification program was undertaken to develop guidelines for operator training and to prepare certification examinations that reflect the actual tasks and duties required of operators in the field. Information about training needs and certification procedures was collected from operators and managers. The results of the study were incorporated into a manual prepared for

Charles E. Ohr; Daniel Cortinovis; Jerrold J. Troyan

1984-01-01

81

Conducting in-depth accident studies  

Microsoft Academic Search

In 1983 the Accident Research Unit at the Institute for Consumer Ergonomics began a major study, sponsored by the UK Department of Transport and three motor companies, to investigate the causes of injury to occupants in car accidents. This study has been under way for nearly ten years and the database of information is one of the most comprehensive of

Pete Thomas; Mo Bradford

1995-01-01

82

Model Validation for Estimating the Leaf Stomatal Conductance in cv. Cabernet Sauvignon Grapevines  

Microsoft Academic Search

The coupled model of assimilation and stomatal conductance (A-gs) was evaluated to estimate leaf stomatal conductance of a drip-irrigated vineyard (Vitis vinifera L. cv. Cabernet Sauvignon) located in the Pencahue Valley (35º22' S, 71°47' W, 150 m.a.s.l.), Maule Region, Chile, during the 2003-2004 and the 2004-2005 growing seasons. Additionally, a calibration of the three parameters mesophyll conductance (gm), maximum specific

Francisco Jara-Rojas; Samuel Ortega-Farías; Héctor Valdés-Gómez; Carlos Poblete; Alejandro del Pozo

2009-01-01

83

Validation of High-Resolution DNA Melting Analysis for Mutation Scanning of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Gene  

PubMed Central

High-resolution melting analysis of polymerase chain reaction products for mutation scanning, which began in the early 2000s, is based on monitoring of the fluorescence released during the melting of double-stranded DNA labeled with specifically developed saturation dye, such as LC-Green. We report here the validation of this method to scan 98% of the coding sequence of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. We designed 32 pairs of primers to amplify and analyze the 27 exons of the gene. Thanks to the addition of a small GC-clamp at the 5? ends of the primers, one single melting domain and one identical annealing temperature were obtained to co-amplify all of the fragments. A total of 307 DNA samples, extracted by the salt precipitation method, carrying 221 mutations and 21 polymorphisms, plus 20 control samples free from variations (confirmed by denaturing high-performance liquid chromatography analysis), was used. With the conditions described in this study, 100% of samples that carry heterozygous mutations and 60% of those with homozygous mutations were identified. The study of a cohort of 136 idiopathic chronic pancreatitis patients enabled us to prospectively evaluate this technique. Thus, high-resolution melting analysis is a robust and sensitive single-tube technique for screening mutations in a gene and promises to become the gold standard over denaturing high-performance liquid chromatography, particularly for highly mutated genes such as CFTR, and appears suitable for use in reference diagnostic laboratories.

Audrezet, Marie-Pierre; Dabricot, Aurelia; Le Marechal, Cedric; Ferec, Claude

2008-01-01

84

Assessment of Parenting Practices Related to Conduct Problems: Development and Validation of the Management of Children's Behavior Scale  

Microsoft Academic Search

We report on the development and initial validation of the parent-report scale, Management of Children's Behavior Scale (MCBS), designed to evaluate parenting practices related to conduct problems in children. Children (N=396, ages 2-14) referred for outpatient treatment and their parents served as participants. We evaluated the composition and consistency of the scale and provided evidence pertaining to concurrent, predictive, and

Francheska Perepletchikova; Alan E. Kazdin

2004-01-01

85

A validation study for vinyl electrical tape end matches.  

PubMed

Fracture matches are considered the strongest conclusion in the forensic examination of rigid materials, such as glass, metal, and paint. However, publications that support the fracture matching of polymeric films, such as tape backings, are limited. This study was designed to determine the validity and error rate associated with conducting end-match (fracture match) examinations on vinyl electrical tape. Test designs varied the source roll of tape, test preparer, or mode of separation from the roll. Results indicated that each affected the resulting severed tape ends. The analysts examining the end matches also had an effect on the results. Eight end matches in the study were not identified by the initial analysts and were considered inconclusive. One end match was misidentified, resulting in one false positive and an error rate of 0.049%. These results support a comprehensive physical and chemical tape comparison regardless of indications of an end match. PMID:21361956

Bradley, Maureen J; Gauntt, Jennifer M; Mehltretter, Andria H; Lowe, Preston C; Wright, Diana M

2011-03-01

86

A molecular dynamics-stochastic model for thermal conductivity of nanofluids and its experimental validation.  

PubMed

A model to predict the enhanced thermal conductivity of water based copper nanofluid on the basis of molecular dynamics simulation coupled with stochastic simulation shows for the first time that the temperature of a copper nanoparticle colliding with a heat source can rise rapidly within the short collision period (e.g., 10-50 ps) estimated by impact dynamics due to phonon transfer. Thereafter the particles undergo Brownian movement in the base fluid and transfer the excess heat in about 2 to 3 ms to the surrounding fluid resulting in an appreciable enhancement of the thermal conductivity of the fluid. Microconvection has minor contribution to the enhanced thermal conductivity of nanofluids. The predicted thermal conductivity of nanofluid and its variation with the volume fraction of the nanoparticles agree well with the present experiments, as well as, with the data reported in the literature. PMID:21449369

Ghosh, Madan Mohan; Roy, Someshwar; Pabi, Shyamal Kumar; Ghosh, Sudipto

2011-03-01

87

College of the Canyons Predictive Validity Studies.  

ERIC Educational Resources Information Center

|Matriculation regulations in California require that community colleges which adopt standardized placement tests demonstrate that the tests are valid predictors of future course success. A positive correlation of at least .35 between test score and subsequent student performance in a particular course is needed to demonstrate the predictive…

College of the Canyons, Valencia, CA. Office of Institutional Development.

88

Establishing the internal and external validity of experimental studies.  

PubMed

The information needed to determine the internal and external validity of an experimental study is discussed. Internal validity is the degree to which a study establishes the cause-and-effect relationship between the treatment and the observed outcome. Establishing the internal validity of a study is based on a logical process. For a research report, the logical framework is provided by the report's structure. The methods section describes what procedures were followed to minimize threats to internal validity, the results section reports the relevant data, and the discussion section assesses the influence of bias. Eight threats to internal validity have been defined: history, maturation, testing, instrumentation, regression, selection, experimental mortality, and an interaction of threats. A cognitive map may be used to guide investigators when addressing validity in a research report. The map is based on the premise that information in the report evolves from one section to the next to provide a complete logical description of each internal-validity problem. The map addresses experimental mortality, randomization, blinding, placebo effects, and adherence to the study protocol. Threats to internal validity may be a source of extraneous variance when the findings are not significant. External validity is addressed by delineating inclusion and exclusion criteria, describing subjects in terms of relevant variables, and assessing generalizability. By using a cognitive map, investigators reporting an experimental study can systematically address internal and external validity so that the effects of the treatment are accurately portrayed and generalization of the findings is appropriate. PMID:11760921

Slack, M K; Draugalis, J R

2001-11-15

89

Construction and validation of a plunge electrode array for three-dimensional determination of conductivity in the heart.  

PubMed

The heart's response to electrical shock, electrical propagation in sinus rhythm, and the spatiotemporal dynamics of ventricular fibrillation all depend critically on the electrical anisotropy of cardiac tissue. Analysis of the microstructure of the heart predicts that three unique intracellular electrical conductances can be defined at any point in the ventricular wall; however, to date, there has been no experimental confirmation of this concept. We report the design, fabrication, and validation of a novel plunge electrode array capable of addressing this issue. A new technique involving nylon coating of 24G hypodermic needles is performed to achieve nonconductive electrodes that can be combined to give moderate-density multisite intramural measurement of extracellular potential in the heart. Each needle houses 13 silver wires within a total diameter of 0.7 mm, and the combined electrode array gives 137 sites of recording. The ability of the electrode array to accurately assess conductances is validated by mapping the potential field induced by a point current source within baths of saline of varying concentration. A bidomain model of current injection in the heart is then used to test an approximate relationship between the monodomain conductivities measured by the array, and the full set of bidomain conductivities that describe cardiac tissue. PMID:18269998

Hooks, Darren A; Trew, Mark L

2008-02-01

90

29 CFR 1607.5 - General standards for validity studies.  

Code of Federal Regulations, 2013 CFR

...through a construct validity study should consist of data showing...standardization. Validity studies should be carried out under...of time and in a majority of cases, progress to a higher level...when technically feasible, a study which is designed to...

2013-07-01

91

A validation study of SCIAMACHY cloud products  

NASA Astrophysics Data System (ADS)

Since clouds play an essential role in the Earth's climate system, it is important to understand the cloud characteristics as well as their distribution on a global scale using satellite observa-tions. One of the main scientific objectives of SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) on ENVISAT is the retrieval of cloud parameters which are also relevant for the study of tropospheric constituents. On the one hand, SCIAMACHY has to be sensitive to low variations in trace gas concentra-tions which means the ground pixel size has to be large enough. On the other hand, such a large pixel size leads to the problem that SCIAMACHY spectra are not well suitable to de-rive a reliable cloud fraction that can be used as input parameter for subsequent retrievals of cloud properties or vertical trace gas columns. Therefore, we use MERIS/ENVISAT spectral measurements with its high spatial resolution as sub-pixel information for the determination of MerIs Cloud fRaction fOr Sciamachy (MICROS). Since MERIS covers an even broader swath width than SCIAMACHY, no problems with spatial and temporal matches of measurements occur. This enables the derivation of a SCIAMACHY cloud fraction with an accuracy much higher as compared with other current cloud fractions that are based on SCIAMACHY's PMD (Polarization Measurement Device) data. We present our new developed MICROS algorithm based on the threshold approach as well as a qualitative validation of our results with MERIS satellite imageries for different locations, especially with respect to bright surfaces such as snow/ice and sands. Moreover, the SCIA-MACHY cloud fractions derived with MICROS serve as input parameter for the satellite cloud retrieval algorithm SACURA (Semi-Analytical CloUd Retrieval Algorithm) in order to retrieve cloud optical thickness, cloud top height, liquid water path, effective radius and cloud albedo for SCIAMACHY. These cloud properties are intercompared with other current cloud products which have been derived for SCIAMACHY as well as for other spaceborne or ground based instruments.

Martinecz, Cornelia; Kokhanovsky, Alexander; Vountas, Marco; Rozanov, Vladimir; Burrows, John P.

92

Viscoelastic study of conducting polymers using quartz crystal microbalance  

Microsoft Academic Search

Application of conducting polymers has been growing widely in different fields such as batteries, solar cells, capacitors and actuators. Mechanical properties of conducting polymers like flexibility, high power to mass ratio and high active strain make them potentially applicable to robotic and automation industries. Obviously, a dynamic model of the actuation phenomenon in conducting polymers is needed to study its

Mehrdad Bahrami Samani; Philip Whitten; Geoffrey Spinks; Christopher Cook

2006-01-01

93

Electrical conductivity and TSDC study of the thermal aging in conductive polypyrrole\\/polyaniline blends  

Microsoft Academic Search

The thermal aging of conducting polypyrrole\\/polyaniline (PPy\\/PA) blends heated at 70°C for up to about 600 hours was studied by d.c. conductivity measurements and by thermally stimulated depolarization current (TSDC) spectroscopy in the temperature range from 80 to 300 K. The composition of the samples varied from pure polypyrrole to pure polyaniline with the PA content increasing in steps of

S. Sakkopoulos; E. Vitoratos; J. Grammatikakis; A. N. Papathanassiou; E. Dalas

2002-01-01

94

High pressure electrical conductivity studies of acid doped polybenzimidazole  

Microsoft Academic Search

Electrical conductivity studies of acid doped poplybenzimidazole (PBI) and 85% phosphoric acid have been carried out. The PBI contained about 600mol% of 85% phosphoric acid and the electrical conductivity was deduced from complex impedance studies which were made at frequencies from 10 to 107Hz. Measurements were made at pressures up to 0.25 GPa and temperatures of about 25, 50 and

J. J Fontanella; M. C Wintersgill; J. S Wainright; R. F Savinell; M Litt

1998-01-01

95

Maternal Attributions and Young Children's Conduct Problems: A Longitudinal Study  

ERIC Educational Resources Information Center

|The association between negative maternal attributions and child conduct problems is well established in correlational studies. However, little is known about how these variables influence each other over time. The present study examined patterns of prediction over time between maternal attributions and pre-school conduct problems. Sixty mothers…

Wilson, Charlotte; Gardner, Frances; Burton, Jennifer; Leung, Sarah

2006-01-01

96

Vision Test Validation Study for the Health Examination Survey Among Youths 12-17 years.  

ERIC Educational Resources Information Center

A validation study of the vision test battery used in the Health Examination Survey of 1966-1970 was conducted among 210 youths 12-17 years-old who had been part of the larger survey. The study was designed to discover the degree of correspondence between survey test results and clinical examination by an opthalmologist in determining the…

Roberts, Jean

97

Vision Test Validation Study for the Health Examination Survey Among Youths 12-17 years.  

ERIC Educational Resources Information Center

|A validation study of the vision test battery used in the Health Examination Survey of 1966-1970 was conducted among 210 youths 12-17 years-old who had been part of the larger survey. The study was designed to discover the degree of correspondence between survey test results and clinical examination by an opthalmologist in determining the…

Roberts, Jean

98

Validation study on avermectine residues in foodstuffs.  

PubMed

Avermectines are antiparasitic agents widely used as veterinary drugs for food producing animals. The European Community, due to their side effects, limited the use of these molecules establishing maximum residue limits (MRLs) in some foods. A validated qualitative and quantitative high performance liquid chromatography method with fluorescence detection (HPLC-FL) is presented for the simultaneous determination of ivermectin (IVM), abemectin (ABA), moxidectin (MOX), eprinomectin (EPR), doramectin (DOR) and emamectin (EMA) in foodstuffs (muscle, eggs and milk). Samples were extracted with acetonitrile, purified with liquid-liquid extraction (LLE), and analysed by HLPC-FL previous derivatization with trifluoroacetic anhydride (TFAA) in presence of 1-methyl-imidazole (MI) and acetic acid. To date, the presented method is the first validated for the matrix eggs, and in accordance with the requirements set by Commission Decision 2002/657/EC. Recoveries of the methods, calculated spiking the samples in the range 5.0-100.0 ?g kg(-1), were 64-83% for muscle, 65-89% for milk and 63-84% for eggs. The precision (CV) ranged between 9.2 and 17.1% for muscle, 9.9 and 16.6% for milk and from 9.4 to 17.4% for eggs. Linearity for the six analytes was calculated from 5.0 to 200.0 ?g kg(-1). The main advantages of the presented method are its rapidity, the specificity, the good precision and recovery that make it very suitable to the detection and determination of avermectines. PMID:21742111

Giannetti, L; Giorgi, A; Necci, F; Ferretti, G; Buiarelli, F; Neri, B

2011-01-13

99

Validation of improved recording site to measure phrenic conduction from surface electrodes in humans.  

PubMed

Phrenic nerve stimulation, electrical (ES) or from cervical magnetic stimulation (CMS), allows one to assess the diaphragm contractile properties and the conduction time of the phrenic nerve (PNCT) through recording of an electromyographic response, traditionally by using surface electrodes. Because of the coactivation of extradiaphragmatic muscles, signal contamination can jeopardize the determination of surface PNCTs. To address this, we compared PNCTs with ES and CMS from surface and needle diaphragm electrodes in five subjects (10 phrenic nerves). At a modified recording site, lower and more anterior than usual (lowest accessible intercostal space, costochondral junction) with electrodes 2 cm apart, surface and needle PNCTs were similar (CMS: 6.0 +/- 0.25 ms surface vs. 6.2 +/- 0.13 ms needle, not significant). Electrodes recording the activity of the most likely sources of signal contamination, i.e., the serratus anterior and pectoralis major, showed distinct responses from that of the diaphragm, their earlier occurrence strongly arguing against contamination. With ES and CMS, apparently uncontaminated signals could be consistently recorded from surface electrodes. PMID:11842028

Verin, Eric; Straus, Christian; Demoule, Alexandre; Mialon, Philippe; Derenne, Jean-Philippe; Similowski, Thomas

2002-03-01

100

Accuracy of dietary recall using the USDA five-step multiple-pass method in men: An observational validation study  

Microsoft Academic Search

ObjectiveThis observational validation study was conducted under controlled conditions to test the accuracy of dietary recall in normal weight, overweight, and obese men using the USDA five-step multiple-pass method for dietary recall.

Joan M. Conway; Linda A. Ingwersen; Alanna J. Moshfegh

2004-01-01

101

A Combined Conductivity and XAS Study of Plastically Crystalline Electrolytes  

NASA Astrophysics Data System (ADS)

We report a study of the conductivity of LiBr and copper salt doped succinonitrile along with X-ray absorption measurements for the bromide and copper ions. The work shows that the ions are in well-ordered sites for most of the plastic phase and relatively high conductivity is due to a small fraction of the ions which are mobile.

Chadwick, A. V.; Berko, A.; Blacklocks, A. N.; Edwards, W.

2010-11-01

102

Validation study of the Japanese version of the faecal incontinence quality of life scale  

PubMed Central

Aim The aim of the present study was to conduct a psychometric validation of the Japanese version of the FIQL (JFIQL). Method A retrospective analysis of data from the JFIQL was conducted. Wexner scores and Faecal Incontinence Severity Index (FISI) scores were collected prospectively in patients with faecal incontinence who visited our centre between 2008 and 2009. For convergent validity, the JFIQL scores were compared with stages on the Wexner scale for lifestyle alteration. To evaluate reliability, Cronbach's alpha was calculated for internal consistency, whereas a test–retest study was performed to evaluate reproducibility. In assessing responsiveness, JFIQL scores before and after treatments were compared in patients whose FISI scores decreased by ? 50%. Results Convergent validity and internal consistency were determined in 70 patients (49 women; median age 68.5 years). The JFIQL scores were significantly associated with lifestyle alteration stages on the Wexner scale, demonstrating convergent validity in all four domains and the generic score. Cronbach's alpha was > 0.7 for generic scores and all domains except Embarrassment. The intraclass correlations for the 27 patients available for the test–retest study were > 0.7 for generic scores and all domains except Embarrassment. The median JFIQL score improved significantly after treatment in the 23 patients whose FISI scores decreased ? 50%, indicating good responsiveness in all four domains and the generic score. Conclusion The JFIQL has been validated and is now ready for use in evaluating the symptom-specific quality of life in Japanese patients with faecal incontinence. What is new in this paper This is the first study validating the Japanese version of the FIQL (JFIQL). The JFIQL was validated not only for convergent validity and reliability, but also for responsiveness, which has never been addressed before. We also validated a generic JFIQL score in addition to scores for four specific domains.

Ogata, H; Mimura, T; Hanazaki, K

2012-01-01

103

Radcalc for Windows validation and benchmark study  

SciTech Connect

Radcalc for Windows, version 2.01 (Radcalc), is a software program developed by Waste Management Federal Services, Inc., Northwest Operations for the US Department of Energy. It is used to generate selected transportation and packaging data necessary for the shipment of radioactive waste materials. Among its applications are the classification of waste per US Department of Transportation regulations, the calculation of heat and daughter products generated as a result of radioactive decay, and the calculation of the radiolytic production of hydrogen gas. The Radcalc program has been extensively tested and validated by comparison of each Radcalc algorithm to hand calculations. An opportunity to benchmark Radcalc hydrogen gas generation calculations to experimental data arose when the Rocky Flats Environmental Technology Site (REFETS) residue stabilization program collected hydrogen gas generation data to determine compliance with requirements for shipment of waste in the TRUPACT-II. Previously, Radcalc had been benchmarked to residue/waste drums tested at RFETS containing contaminated solid inorganic materials in plastic bags. In this paper Radcalc is compared with data collected for contaminated solid organic waste. The contamination is predominantly due to plutonium and americium isotopes. The information provided by RFETS includes decay heat, hydrogen gas generation rates, calculated hydrogen G{sub eff} values (molecules of hydrogen formed per 100-eV decay heat energy released), and waste material. Radcalc cases are run using RFETS G{sub eff} values, TRUPACT-II G values, and dose-dependent G values. Work on calculating the radiolytic production of hydrogen gas and related increase in package pressure has also been performed at the Savannah River Site (SRS) in support of efforts to ship nuclear materials in the 9975 package. The calculations made at SRS are contained in an Excel spreadsheet. The SRS model has been compared with experimental data collected at SRS and at Los Alamos National Laboratory.

McFadden, J.G.; Knepp, J.R.

1999-07-01

104

Validation Studies of the Global Physical Activity Questionnaire (GPAQ)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

105

Validation Studies of the Flemish Physical Activity Computerized Questionnaire (FPACQ)  

Cancer.gov

Validation Studies of the Flemish Physical Activity Computerized Questionnaire (FPACQ) Matton et al. 2007 See reference #97 Methods Relation of FPACQ to a triaxial accelerometer, (RT3), and a written 7-day activity record. (Spearman correlations) Sample 68

106

Validation Studies of the Flemish Physical Activity Computerized Questionnaire (FPACQ)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

107

Validation Studies of the The Modified Baecke Questionnaire (MBQ)  

Cancer.gov

Validation Studies of the The Modified Baecke Questionnaire (MBQ) Hertogh et al. 2008 See reference #85 Methods MBQ score compared to doubly labeled water derived physical activity ratio (PAR). (Spearman correlations) Sample 10 men and 11 women 60

108

Validation Studies of the Seven Day Physical Activity Recall (PAR)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

109

Validation Studies of the Rapid Assessment of Physical Activity (RAPA)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

110

Validation Studies of the Active Australia Survey (AAS)  

Cancer.gov

Validation Studies of the Active Australia Survey (AAS) Heesch et al. 2011 See reference #124 Methods Relation between The Active Australia Survey (AAS) daily walking minutes and total physical activity (PA) minutes (walking, moderate-intensity PA and

111

Validation Studies of the Active Australia Survey (AAS)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

112

Validation Studies of the Allied Dunbar National Fitness Survey (ADNFS)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

113

Validation Studies of the Physical Activity Scale (PAS)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

114

Validation Studies of the Physical Activity Recall Instrument (PARI)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

115

Validation Studies of the International Physical Activity Questionnaire (IPAQ)  

Cancer.gov

Validation Studies of the International Physical Activity Questionnaire (IPAQ) van der Ploeg et al. 2010 See reference #125 Methods Relation between IPAQ estimates of total time walked per week and a CSA accelerometer worn for 7 consecutive days as an

116

Validation Studies of the International Physical Activity Questionnaire (IPAQ)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

117

Validation Studies of the Historical Leisure Activity Questionnaire (HLAQ)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

118

Airlift Capabilities Estimation Prototype: A Case Study in Model Validation.  

National Technical Information Service (NTIS)

This study investigates the application of a life cycle approach to the validation of operational models. The classic waterfall life cycle from software engineering is adapted for use on mathematical models by defining four stages of model development. Ea...

R. McCanne

1993-01-01

119

Validation Studies of the Seven Day Physical Activity Recall (PAR)  

Cancer.gov

Validation Studies of the Seven Day Physical Activity Recall (PAR) Wilkinson et al. 2004 See reference #111 Methods 7-day physical activity recall (PAR), including alternative PAR scoring algorithms compared to pedometer readings (3 days step counts).

120

Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study  

Microsoft Academic Search

Background: In the assessment of severity in community acquired pneumonia (CAP), the modified Brit- ish Thoracic Society (mBTS) rule identifies patients with severe pneumonia but not patients who might be suitable for home management. A multicentre study was conducted to derive and validate a practi- cal severity assessment model for stratifying adults hospitalised with CAP into different management groups. Methods:

W S Lim; M M van der Eerden; R Laing; W G Boersma; N Karalus; G I Town; S A Lewis; J T Macfarlane

2009-01-01

121

Validation of the Instructional Strategy Diagnostic Profile (ISDP): Empirical Studies. Final Report.  

ERIC Educational Resources Information Center

The Instructional Strategy Diagnostic Profile (ISDP) was designed to enable instructional developers and evaluators to predict the effectiveness of, and prescribe improvements for existing instructional materials. Experimental studies were conducted in introductory college statistics and physics classes to validate the ISDP and its accompanying…

Merrill, M. David; Wood, Norman D.

122

Validation Study on the Classification of Non-Curricular Students, Fall 1976.  

ERIC Educational Resources Information Center

|A study of the Virginia Community College System's Non-Curricular Classification System, which classifies students not enrolled in a particular educational program by ten goal categories, was conducted to assess the validity of classifying non-curricular students by their educational goals, to determine whether students agreed or disagreed with…

Virginia State Dept. of Community Colleges, Richmond.

123

Validation study of the USDA’s data quality evaluation system  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Nutrient Data Laboratory (NDL) of USDA conducted a validation study of the USDA Data Quality Evaluation System (DQES). The system evaluates the quality of analytical data by rating important documentation concerning the analytical method, analytical quality control, number of samples, sampling ...

124

Academic Self-Efficacy as a Predictor of College Outcomes: Two Incremental Validity Studies  

ERIC Educational Resources Information Center

|A growing body of literature supports the relationship between students' self-efficacy beliefs for academic tasks and milestones and their academic performance. Not surprisingly, some researchers have investigated the role that academic self-efficacy beliefs play in predicting college success. Two incremental validity studies were conducted to…

Gore, Paul A. Jr

2006-01-01

125

The popliteal lymph node assay: results of a preliminary interlaboratory validation study  

Microsoft Academic Search

The popliteal lymph node (PLN) assay was proposed to predict possible autoimmune effects of xenobiotics. A preliminary interlaboratory validation study of the PLN assay was conducted in Wistar rats. Three laboratories tested in blind fashion four compounds, namely chlorpromazine, zimeldine, hydrazine and streptozotocin, which were reported to cause autoimmune-like reactions in humans, and one compound, i.e. barbital, which was not,

T Vial; J Carleer; B Legrain; F Verdier; J Descotes

1997-01-01

126

Conducting Internet Research With the Transgender Population: Reaching Broad Samples and Collecting Valid Data  

PubMed Central

Health research on transgender people has been hampered by the challenges inherent in studying a hard-to-reach, relatively small, and geographically dispersed population. The Internet has the potential to facilitate access to transgender samples large enough to permit examination of the diversity and syndemic health disparities found among this population. In this article, we describe the experiences of a team of investigators using the Internet to study HIV risk behaviors of transgender people in the United States. We developed an online instrument, recruited participants exclusively via websites frequented by members of the target population, and collected data using online quantitative survey and qualitative synchronous and asynchronous interview methods. Our experiences indicate that the Internet environment presents the investigator with some unique challenges and that commonly expressed criticisms about Internet research (e.g., lack of generalizable samples, invalid study participants, and multiple participation by the same subject) can be overcome with careful method design, usability testing, and pilot testing. The importance of both usability and pilot testing are described with respect to participant engagement and retention and the quality of data obtained online.

Miner, Michael H.; Bockting, Walter O.; Romine, Rebecca Swinburne; Raman, Sivakumaran

2013-01-01

127

Physical Chemical Studies of Conducting Polymers Fundamental and Applied.  

National Technical Information Service (NTIS)

Reversible electroactive doping of conducting polymers was studied with a view toward the determination of important electroactive mechanisms in the polymers. Also the transport of solutes in polymer films was investigated. Research eventually focused on ...

H. Reiss

1993-01-01

128

A Preliminary Study of Cyclic Voltammetry of a Conducting Polymer  

NASA Astrophysics Data System (ADS)

An electroactivity study of active species in a conducting polymer uses the Cyclic Voltammetry (CV) analytical technique. A technique is chosen in which the potential of an electrode is the controlled variable, while the current is the observed variable. Two plates of platinum were used as a counting electrode and a working electrode, respectively. A reference electrode used Ag/AgCl. Polypyrrole (PPy), polythiophene (PT) and poly (3-acetic acid thiophene) (PT3AA) were conducting polymer material synthesized using iron (III) chloride as a catalyst. The effect of a supporting electrolyte of sodium perchlorate anhydrous NaClO4.H2O on conducting polymers is also studied.

Hasiah, S.; Ibrahim, K.; Senin, H. B.; Mohamed, Faizatul Shima

2007-05-01

129

Structural, thermal studies and ionic conductivity of doped polymer electrolytes  

NASA Astrophysics Data System (ADS)

In this paper we present, the structural, thermal studies and ionic conductivity of cadmium chloride (CdCl2) doped polyethylene oxide (PEO). The XRD, FTIR, SEM and DSC were used to confirm the structural, chemical, morphology and thermal studies of doped PEO. The ionic conductivity measurement was done at different temperatures. The polymer electrolyte observed a maximum ionic conductivity of the order of 2.5×10-7 Sm/cm at 303K. The obtained results suggest that, these polymer systems are suitable candidates for solid state battery, optoelectronics display & electro chromic devices etc.

Kilarkaje, Subramanya; Raghu, S.; Devendrappa, H.

2012-06-01

130

Guidelines for Conducting Positivist Case Study Research in Information Systems  

Microsoft Academic Search

The case study research approach is widely used in a number of different ways within the information systems community. This paper focuses on positivist, deductive case study research in information systems. It provides clear definitions of important concepts in positivist case study research and illustrates these with an example research study. A critical analysis of the conduct and outcomes of

Graeme G. Shanks

2002-01-01

131

Method validation study of hypoglycin A determination in ackee fruit.  

PubMed

A study was conducted to validate the performance characteristics of a published method entitled "Reversed-Phase Liquid Chromatographic Detection of Hypoglycin A in Canned Ackee Fruit Sample." Hypoglycin A (HG-A) was extracted from ackee fruit with 80% ethanol-water, centrifuged, and filtered; the sample extract then was reacted with phenylisothiocyanate. HG-A was separated by reversed-phase chromatography as the phenylthiocarbamyl derivative and detected at the low nanogram level using a UV detector at 254 nm. A study was conducted to determine recovery of HG-A added to a control ackee fruit sample. A control sample containing a low level of HG-A was spiked with 403.2, 201.6, 96.8, and 48.4 microg HG-A/g ackee fruit, respectively. Twelve replicates were analyzed for each spike level. The mean percent recovery +/- standard deviation for spike levels 403.2, 201.6, 96.8, and 48.4 microg HG-A/g were 94.37 +/- 1.27, 99.12 +/- 2.09, 107.95 +/- 5.42, and 129.18 +/- 15.32%, respectively. The percent coefficient of variation (%CV) for spike levels 403.2, 201.6, 96.8, and 48.4 microg HG-A/g were 1.35, 2.11, 5.02, and 11.86%, respectively. The recovery data indicate that HG-A can be recovered from ackee fruit with excellent accuracy and precision. Precision data obtained from replicate assays of ackee fruit naturally contaminated with low, medium, and high HG-A levels is presented. PMID:12180690

Ware, George M

132

Longitudinal Studies: Designs, Validity, Practicality, and Value  

ERIC Educational Resources Information Center

|Aiming to encourage longitudinal studies in science education, we clarify conceptual and methodological aspects of longitudinal research. We use the studies that other articles in this issue describe to illustrate these aspects. The illustrations range from attempts to promote long-term change through experimental teaching to investigations that…

White, Richard T.; Arzi, Hanna J.

2005-01-01

133

AC Conductivity Studies of Lithium Based Phospho Vanadate Glasses  

NASA Astrophysics Data System (ADS)

Glasses in the system xLi2SO4-20Li2O-(80-x) [80P2O5-20V2O5] (5>=x>=20 mol%) has been prepared by melt quenching method. Dc and ac conductivity has been studied over a wide range of frequency (10 Hz to 10 MHz) and temperature (298 K-523 K). The dc conductivity found to increase with increase of Li2SO4 concentration. The ac conductivities have been fitted to the Almond-West type single power law equation ?(?) = ?(0)+A?s where `s' is the power law exponent. The ac conductivity found to increase with increase of Li2SO4 concentration. An attempt is made to elucidate the enhancement of lithium ion conduction in phosphor-vanadate glasses by considering the expansion of network structure.

Nagendra, K.; Babu, G. Satish; Reddy, C. Narayana; Gowda, Veeranna

2011-07-01

134

18 CFR 5.15 - Conduct of studies.  

Code of Federal Regulations, 2013 CFR

...proposal to modify an ongoing study pursuant to paragraphs...appropriate to the facts of the case, a demonstration that: (1) Approved studies were not conducted as...appropriate to the facts of the case, a statement explaining...objectives of any approved study could not be met...

2013-04-01

135

Study of potassium-ion-conducting electrolytes for electrochromic windows  

NASA Astrophysics Data System (ADS)

Different anhydrous potassium ion conducting polymer electrolytes have been studied: (POE)nKTFSI (trifluorosulfonimide), plasticized (POE)nKTFSI, (PEM)nKTFSI, and (POE-Acetal)nKTFSI. DSC and conductivity measurements have been used to characterize these electrolytes. Several solutions to avoid crystallization have been examined. The best conductivity has been obtained with (POE-Acetal)nKTFSI. This electrolyte exhibits good transmission in the VIS-IR region. The response time of cells using these electrolytes and Prussian blue and KxWO3 as electrodes has been measured and compared.

Beraud, Jean-Guy; Deroo, Daniel

1992-11-01

136

Prediction of hydraulic conductivity and conductive fracture frequency by multivariate analysis of data from the Klipperaas study site.  

National Technical Information Service (NTIS)

The present study is a pilot study on the possibility to predict the hydraulic conductivity and conductive fracture frequency in boreholes in crystalline rock using multivariate data analysis. The data set included data from core mapping, fracture filling...

J. E. Andersson L. Lindqvist

1989-01-01

137

Study Suggests Physicians Conduct Unnecessary Surveillance Colonoscopies: Questions and Answers  

Cancer.gov

The study was designed to understand the physician factors that influence the effective use of colorectal cancer surveillance in the United States. Researchers conducted this study to determine how gastroenterologists and general surgeons recommend surveillance for various polyps detected during an initial screening colonoscopy and compare their recommendations to published clinical practice guidelines.

138

A Validation Study of the Adolescent Dissociative Experiences Scale  

ERIC Educational Resources Information Center

Objective: The purpose of this study was to further the validation process of the Adolescent Dissociative Experiences Scale (A-DES). In this study, a 6-item Likert response format with descriptors was used when responding to the A-DES rather than the 11-item response format used in the original A-DES. Method: The internal reliability and construct…

Keck Seeley, Susan. M.; Perosa, Sandra, L.; Perosa, Linda, M.

2004-01-01

139

Sources of Self-Efficacy in Mathematics: A Validation Study  

ERIC Educational Resources Information Center

The purpose of this study was to develop and validate items with which to assess A. Bandura's (1997) theorized sources of self-efficacy among middle school mathematics students. Results from Phase 1 (N=1111) were used to develop and refine items for subsequent use. In Phase 2 of the study (N=824), a 39-item, four-factor exploratory model fit best.…

Usher, Ellen L.; Pajares, Frank

2009-01-01

140

California Diploma Project Technical Report III: Validity Study--Validity Study of the Health Sciences and Medical Technology Standards  

ERIC Educational Resources Information Center

This study is a validity study of the recently revised version of the Health Science Standards. The purpose of this study is to understand how the Health Science Standards relate to college and career readiness, as represented by survey ratings submitted by entry-level college instructors of health science courses and industry representatives. For…

McGaughy, Charis; Bryck, Rick; de Gonzalez, Alicia

2012-01-01

141

Recent Studies of RF Breakdown Physics in Normal Conducting Cavities  

SciTech Connect

The operating accelerating gradient in normal conducting accelerating structures is often limited by rf breakdown. The behavior of the rf breakdown depends on multiple parameters, including the input rf power, rf circuit, cavity shape and material. Here we discuss recent experimental data and theoretical studies of rf breakdown physics.

Dolgashev, Valery; /SLAC

2012-06-11

142

Endoscopic carpal tunnel release and nerve conduction studies  

Microsoft Academic Search

We investigated the outcome of endoscopic carpal tunnel release (ECTR) for patients with carpal tunnel syndrome (CTS) in comparison with the results of preoperative nerve conduction studies. The compound muscle action potential (CMAP) of the abductor pollicis brevis muscle (APB) and the second lumbrical muscle (L2) was recorded following median nerve stimulation at the wrist. A total of 38 hands

Hiroyasu Ueno; Kazuo Kaneko; Toshihiko Taguchi; Yasunori Fuchigami; Hideaki Fujimoto; Shinya Kawai

2001-01-01

143

Recent Studies of RF Breakdown Physics in Normal Conducting Cavities  

SciTech Connect

The operating accelerating gradient in normal conducting accelerating structures is often limited by rf breakdown. The behavior of the rf breakdown depends on multiple parameters, including the input rf power, rf circuit, cavity shape and material. Here we discuss recent experimental data and theoretical studies of rf breakdown physics.

Dolgashev, Valery [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025 (United States)

2010-11-04

144

Electromyography and nerve conduction study in autosomal dominant olivopontocerebellar atrophy  

Microsoft Academic Search

Electromyographic examination and studies of motor and sensory conduction velocities were performed in 11 patients with a presumptive diagnosis of olivopontocerebellar atrophy with autosomal dominant transmission. Peripheral nervous system involvement was shown in eight. In two patients with early onset of disease, electrophysiological alterations clearly pointed to severe axonal degeneration, whereas in six they were compatible with slight demyelination.

L. Carenini; G. Finocchiaro; S. Di Donato; A. Visciani; S. Negri

1984-01-01

145

Conducting a qualitative culture study of pediatric palliative care.  

PubMed

While conducting a grounded theory study of Chinese American and Mexican American families' experiences in pediatric palliative care, we encountered a number of unanticipated challenges regarding project development, Institutional Review Boards, recruitment, data collection, and data analysis. In this article, we describe our experiences, strategies, and insights for the benefit of other researchers and clinicians in the field. PMID:19001106

Davies, Betty; Larson, Judith; Contro, Nancy; Reyes-Hailey, Carlos; Ablin, Arthur R; Chesla, Catherine A; Sourkes, Barbara; Cohen, Harvey

2008-11-10

146

Genome-wide association study of conduct disorder symptomatology  

Microsoft Academic Search

Conduct disorder (CD) is one of the most prevalent childhood psychiatric conditions, and is associated with a number of serious concomitant and future problems. CD symptomatology is known to have a considerable genetic component, with heritability estimates in the range of 50%. Despite this, there is a relative paucity of studies aimed at identifying genes involved in the susceptibility to

D M Dick; F Aliev; R F Krueger; A Edwards; A Agrawal; M Lynskey; P Lin; M Schuckit; V Hesselbrock; J Nurnberger; L Almasy; B Porjesz; H J Edenberg; K Bucholz; J Kramer; S Kuperman; L Bierut

2011-01-01

147

Hermeneutic Inquiry in the Study of Human Conduct  

Microsoft Academic Search

Interest is growing in the hermeneutic or interpretive approach to the study of human conduct. This article draws upon the work of Martin Heidegger to compare hermeneutics with the other major paradigms of inquiry and explanation in psychology: rationalism (cognitivism and structuralism) and empiricism (experimentalism and behaviorism). The comparison is threefold: in terms of their view of the form and

Martin J. Packer

1985-01-01

148

Paraphasias in Multilingual Conduction Aphasia: A Single Case Study  

ERIC Educational Resources Information Center

|Conduction aphasia is a type of fluent aphasia, which is caused due to the damage to the supramarginal gyrus and arcuate fasciculus resulting in repetition disturbance. It has been speculated that linguistic system in bilingual aphasics can breakdown in different ways across languages. There is a lack of detailed linguistic studies in specific…

Hegde, Medha; Bhat, Sapna

2007-01-01

149

Estimating Unsaturated Hydraulic Conductivity: Study the Effect of Tortuosity Factor  

NASA Astrophysics Data System (ADS)

Unsaturated soil hydraulic conductivity is one of the key soil hydraulic properties that, in one hand, is widely used in the studies of water and solute transport in soils, and on the other hand its direct measurement is time consuming and expensive. In this research, in order to study tortuosity factor (l) in the Burdine-Brooks-Corey (BBC hereafter), 59 soil samples from the GRIZZLY database were used. Using a sensitivity analysis, sensitive parameters of this model were determined. To study tortuosity factor, its different values e.g. 2, 1, 0.5, 0, -0.5, -1 and -2 were used in the estimation of unsaturated hydraulic conductivity. The results of sensitivity analysis showed that BBC model is more sensitive to the saturated water content and pore size distribution index. Whereas, the BBC model is less sensitive to tortuosity factor and saturated hydraulic conductivity. The calculated statistical parameter SAE in estimation of unsaturated hydraulic conductivity indicated that the BBC model error with l=2 is less than other values. The results also showed that tortuosity factor is linearly correlated with the power of BCC model with goodness of fit R2=0.96. Based on this approach, tortuosity factor was removed from BCC model, and a new empirical equation was developed to estimate unsaturated hydraulic conductivity. This model was verified using 33 samples of the UNSODA database. The results showed that the developed empirical equation estimated unsaturated hydraulic conductivity better than BCC model in which tortuosity factor was assumed to be equal to 2. Acknowledgments The authors are grateful to Drs. M.Th. van Genuchten and R. Haverkamp for providing the UNSODA and GRIZZLY data sets.

Ghanbarian-Alavijeh, Behzad; Abbasi, Fariborz

2010-05-01

150

Validation study for secretarial/administrative classifications using computer-based testing  

SciTech Connect

This paper presents the results of a content and concurrent criterion-related validity study conducted at Los Alamos National Laboratory for clerical, secretarial and administrative classifications using computer-based testing. The advantages and disadvantages of different types of testing software incorporated in the study are explored. Job analysis methodology, adverse impact analysis, procedure for establishing cut-off score and problems associated with criterion development and restriction of range are discussed. 6 tabs.

Burns, J.M.

1991-01-01

151

Application of reliability models to studies of biomarker validation.  

PubMed Central

We present a model of biomarker validation developed in our laboratory, the results of the validation study, and the impact of the estimation of the variance components on the design of future molecular epidemiologic studies. Four different biomarkers of exposure are illustrated: DNA-protein cross-link (DNA-PC), DNA-amino acid cross link (DNA-AA), metallothionein gene expression (MT), and autoantibodies to oxidized DNA bases (DNAox). The general scheme for the validation experiments involves n subjects measured on k occasions, with j replicate samples analyzed on each occasion. Multiple subjects, occasions, and replicates provide information on intersubject, intrasubject, and analytical measurement variability, respectively. The analysis of variance showed a significant effect of batch variability for DNA-PC and MT gene expression, whereas DNAox showed a significant between-subject variability. Among the amino acids tested, cysteine and methionine showed a significant contribution of both batch and between-subject variability, threonine showed between-subject variability only, and tyrosine showed between-batch and between-subject variability. The total variance estimated through the experiment was used to calculate the minimum sample size required for a future epidemiologic study including the same biomarkers used for the reliability study. Such validation studies can detect the various components of variability of a biomarker and indicate needed improvements of the assay, along with possible use in field studies.

Taioli, E; Kinney, P; Zhitkovich, A; Fulton, H; Voitkun, V; Cosma, G; Frenkel, K; Toniolo, P; Garte, S; Costa, M

1994-01-01

152

A comparative study of hydraulic conductivity estimations using geostatistics  

NASA Astrophysics Data System (ADS)

Three approaches for estimating the hydraulic conductivity ( K) of the Trifa aquifer, Morocco were investigated: (1) kriging of the K values obtained from pumping tests, (2) cokriging of the pumping test data with electrical resistivity data as a secondary variable, and (3) cokriging of the pumping test data with the slope of the water table. Gauss-transformed values of the variables are used because they provide more robust variograms and transformed values of the primary and secondary variables show correlations higher than the raw values, which is beneficial in cokriging. In cokriging with electrical resistivity, two zones are considered since the geological deposits are different from the north to the south of the aquifer, which is reflected in different correlations between the variables. Comparison of the three approaches is based mainly on the estimation errors, and to a lesser degree on the cross-validations of the corresponding variogram models and general considerations, like the measurements’ reliability and aquifer make-up. The best-estimated K is given by cokriging with the slope of the water table and is therefore preferred for further use in groundwater flow modeling. Thus, electrical resistivity or the slope of the water table can both be used as secondary variables to estimate K, especially in heterogeneous aquifers with lateral variations in lithology, as is the case of the Trifa aquifer.

El Idrysy, El Houcyne; de Smedt, Florimond

2007-05-01

153

Validation Studies of the Central Sweden Physical Activity Questionnaire (CSPAQ)  

Cancer.gov

Validation Studies of the Central Sweden Physical Activity Questionnaire (CSPAQ) Norman et al. 2001 See reference #19 Methods Relationship of CSPAQ to two 7-day activity records Sample 111 men; 44-78 years of age Summary Results SC C SD 44-64 years 0.63 0.63 0.65 65-78

154

A Validation Study of Early Adolescents' Pubertal Self-Assessments  

ERIC Educational Resources Information Center

|This study aimed to determine whether self-assessed puberty is sufficiently reliable and valid to substitute for physician examination when feasibility of physician examination is low (e.g., behavioral research). Adolescents (convenience sample N = 178 endocrinology patients and N = 125 from educational trial; mean age 12.7 and 11.3 years,…

Schmitz, Katharine E.; Hovell, Melbourne F.; Nichols, Jeanne F.; Irvin, Veronica L.; Keating, Kristen; Simon, Gayle M.; Gehrman, Christine; Jones, Kenneth Lee

2004-01-01

155

A Validation Study of Early Adolescents' Pubertal Self-Assessments  

ERIC Educational Resources Information Center

This study aimed to determine whether self-assessed puberty is sufficiently reliable and valid to substitute for physician examination when feasibility of physician examination is low (e.g., behavioral research). Adolescents (convenience sample N = 178 endocrinology patients and N = 125 from educational trial; mean age 12.7 and 11.3 years,…

Schmitz, Katharine E.; Hovell, Melbourne F.; Nichols, Jeanne F.; Irvin, Veronica L.; Keating, Kristen; Simon, Gayle M.; Gehrman, Christine; Jones, Kenneth Lee

2004-01-01

156

Homework Purpose Scale for Middle School Students: A Validation Study  

ERIC Educational Resources Information Center

The purpose of the present study is to test the validity of scores on the Homework Purpose Scale (HPS) for middle school students. The participants were 1,181 eighth graders in the southeastern United States, including (a) 699 students in urban school districts and (b) 482 students in rural school districts. First, confirmatory factor analysis was…

Xu, Jianzhong

2011-01-01

157

Validation Studies of the Rapid Assessment of Physical Activity (RAPA)  

Cancer.gov

Validation Studies of the Rapid Assessment of Physical Activity (RAPA) Topolski et al. 2006 See reference #109 Methods RAPA compared to CHAMPS, BRFSS and PACE, (Spearman rank-order correlation coefficients) Sample 115 elderly, 72% female mean age 73.3

158

A Cross-Validation Study of the Posttraumatic Growth Inventory  

ERIC Educational Resources Information Center

|This article is a cross-validation of R. G. Tedeschi and L. G. Calhoun's (1996) original study of the development of the Posttraumatic Growth Inventory (PTGI). It describes several psychometric properties of scores on the PTGI in a sample of middle- to old-aged adults with a history of cardiovascular disease. The results did not support the…

Sheikh, Alia I.; Marotta, Sylvia A.

2005-01-01

159

Understanding Foreign Language Learning Strategies: A Validation Study  

ERIC Educational Resources Information Center

The present work aims to contribute to our understanding of the underlying dimensions of language learning strategies in foreign language contexts. The study analyzes alternative factor structures underlying a recently developed instrument (Tragant and Victori, 2012) and it includes the age factor in the examination of its construct validity. The…

Tragant, Elsa; Thompson, Marilyn S.; Victori, Mia

2013-01-01

160

Validation Studies of the Allied Dunbar National Fitness Survey (ADNFS)  

Cancer.gov

Validation Studies of the Allied Dunbar National Fitness Survey (ADNFS) Brownbill et al. 2002 See reference #03 Methods Relation between past physical Activity (ADNFS) and BMD by DPX-MD and walking speed (in hallway), and stair climbing (two sample t-tests) Sample 136

161

Validation Studies of the Physical Activity Recall Instrument (PARI)  

Cancer.gov

Validation Studies of the Physical Activity Recall Instrument (PARI) Timperio et al. 2003 See reference #108 Methods PARI compared to MTI/CSA accelerometer worn for seven days. (Spearman’s rank order coefficient) Sample 122 (47% men) males mean age 37.8

162

Validation Studies of the Physical Activity Scale (PAS)  

Cancer.gov

Validation Studies of the Physical Activity Scale (PAS) Aadahl et al. 2003 See reference #61 Methods Relation between PAS and 4 d of accelerometry (CSA 7164) and physical activity diary in 40 volunteer men (Spearman rank-order correlation) Sample 40

163

Understanding Foreign Language Learning Strategies: A Validation Study  

ERIC Educational Resources Information Center

|The present work aims to contribute to our understanding of the underlying dimensions of language learning strategies in foreign language contexts. The study analyzes alternative factor structures underlying a recently developed instrument (Tragant and Victori, 2012) and it includes the age factor in the examination of its construct validity. The…

Tragant, Elsa; Thompson, Marilyn S.; Victori, Mia

2013-01-01

164

Rap-Music Attitude and Perception Scale: A Validation Study  

ERIC Educational Resources Information Center

Objective: This study tests the validity of the Rap-music Attitude and Perception (RAP) Scale, a 1-page, 24-item measure of a person's thoughts and feelings surrounding the effects and content of rap music. The RAP was designed as a rapid assessment instrument for youth programs and practitioners using rap music and hip hop culture in their work…

Tyson, Edgar H.

2006-01-01

165

The bogus pipeline as lie detector: Two validity studies  

Microsoft Academic Search

Two studies, using a total of 109 undergraduates as Ss, tested the validity of the bogus pipeline procedure for eliciting truthful responses from Ss in social psychological experiments. Ss were illegitimately informed about how to perform well on an experimental test, were tested, and then were asked whether they had possessed this prior information. As compared to Ss responding to

Barbara Quigley-Fernandez; James T. Tedeschi

1978-01-01

166

A Cross-Validation Study of the Posttraumatic Growth Inventory  

ERIC Educational Resources Information Center

This article is a cross-validation of R. G. Tedeschi and L. G. Calhoun's (1996) original study of the development of the Posttraumatic Growth Inventory (PTGI). It describes several psychometric properties of scores on the PTGI in a sample of middle- to old-aged adults with a history of cardiovascular disease. The results did not support the…

Sheikh, Alia I.; Marotta, Sylvia A.

2005-01-01

167

A Validation Study of the Existential Anxiety Scale.  

ERIC Educational Resources Information Center

|Logotherapy is a meaning-centered psychotherapy which focuses on both the meaning of human existence and the personal search for meaning. If the will to search for meaning is frustrated, "existential frustration" may result. This study validates the Existential Anxiety Scale (EAS) developed by Good and Good (1974). Basic principles of logotherapy…

Hullett, Michael A.

168

Teachers' Engagement at Work: An International Validation Study  

ERIC Educational Resources Information Center

|This study explored the validity of the Utrecht Work Engagement Scale in a sample of 853 practicing teachers from Australia, Canada, China (Hong Kong), Indonesia, and Oman. The authors used multigroup confirmatory factor analysis to test the factor structure and measurement invariance across settings, after which they examined the relationships…

Klassen, Robert M.; Aldhafri, Said; Mansfield, Caroline F.; Purwanto, Edy; Siu, Angela F. Y.; Wong, Marina W.; Woods-McConney, Amanda

2012-01-01

169

Dimensions of Intuition: First-Round Validation Studies  

ERIC Educational Resources Information Center

|This study utilized confirmatory factor analysis (CFA), canonical correlation analysis (CCA), regression analysis (RA), and correlation analysis (CA) for first-round validation of the researcher's Dimensions of Intuition (DOI) instrument. The DOI examined 25 personal characteristics and situations purportedly predictive of intuition. Data was…

Vrugtman, Rosanne

2009-01-01

170

A quantitative approach to perceived health status: a validation study  

Microsoft Academic Search

The current recognition of the importance of perceived health status as a predictor of need for, and utilisation of, health services has led to attempts to produce indicators which assess subjective rather than objective health problems. The development of the Nottingham Health Profile is described, together with a study which tested the validity of the instrument on four groups of

S M Hunt; S P McKenna; J McEwen; E M Backett; J Williams; E Papp

1980-01-01

171

Using triangulation to validate themes in qualitative studies  

Microsoft Academic Search

Purpose – The purpose of this paper is to provide instructional guidance on how to increase validity and reduce subjectivity in qualitative studies, such as grounded theory. The paper also demonstrates how different techniques can help management research by including informants\\/managers in a time efficient way. Design\\/methodology\\/approach – This paper describes how three complementary triangulation methods can be used for

Karsten Jonsen; Karen A. Jehn

2009-01-01

172

Using Empirical Bayes Techniques in the Law School Validity Studies  

Microsoft Academic Search

The law school validity studies are primarily concerned with the prediction of first-year average in law school from Law School Aptitude Test score and undergraduate grade point average. Traditionally, a separate admitting equation is estimated in each law school by the method of least squares based on data from students who attended the law school in recent years. These least

Donald B. Rubin

1980-01-01

173

Science Sampler: Validating assessment--Teacher study groups  

NSDL National Science Digital Library

Teacher study groups are a valuable method of examining the validity of classroom assessments and determining how well the assessments align with student learning goals. The implementation of teacher study groups is based on a model from the Schools Around the World Academy for Teaching Excellence (Council for Basic Education 2000). The teacher study groups are composed of four to six teachers. Often a teacher solicits group members by sending out flyers to the faculty to find interested volunteers.

Peters, Erin

2008-01-01

174

Validity of repeated dietary measurements in a dietary intervention study.  

PubMed

The aim of the study was to evaluate the compliance in a dietary intervention study. When drawing conclusions about the relationship between dietary intake and disease occurrence/disease-related variables it is important to obtain valid dietary data. 20 healthy, non-smoking normal-weight omnivores changed from a mixed to a lactovegetarian diet. Dietary surveys (four 24 h recalls per person and time-period), urinary and faecal sample collections were performed before and 3, 6 and 12 months after the dietary shift. The validation of energy, protein, sodium and potassium yielded approximately the same ratio of dietary intake to biological marker at 0 and 3 months. This ratio decreased towards 6 months and continued to decrease towards 12 months. The fibre intake was compared to the total faecal weight directly and indirectly by calculating the fibre intake from the stool weight, the water content in faeces and the excretion of short-chain fatty acids (SCFAs). These four methods of fibre validation showed that the ratio of dietary intake to biological marker was always highest at 12 months, indicating an overestimation of the fibre intake at the end of the study. This is the first time these methods of validating fibre intake have been used in an epidemiological study. The ratio of dietary calcium intake to urinary and faecal calcium excretion did not show any statistical difference between the period before and 3 months after the dietary shift. To conclude, almost all investigated dietary data show approximately the same validity before and 3 months after the dietary shift, and show the least validity 12 months after the dietary shift. Thus, this study demonstrates that it is difficult to obtain valid dietary data 1 year after a drastic dietary change, indicating a decreased compliance to the new dietary regimen at the end of the 1 year study period. This represents important information when attempting to relate biological effects to dietary intake, and illustrates the importance of using biological markers for food intake in dietary surveys. PMID:1330511

Johansson, G; Callmer, E; Gustafsson, J A

1992-10-01

175

Environmental education curriculum evaluation questionnaire: A reliability and validity study  

NASA Astrophysics Data System (ADS)

The intention of this research project was to bridge the gap between social science research and application to the environmental domain through the development of a theoretically derived instrument designed to give educators a template by which to evaluate environmental education curricula. The theoretical base for instrument development was provided by several developmental theories such as Piaget's theory of cognitive development, Developmental Systems Theory, Life-span Perspective, as well as curriculum research within the area of environmental education. This theoretical base fueled the generation of a list of components which were then translated into a questionnaire with specific questions relevant to the environmental education domain. The specific research question for this project is: Can a valid assessment instrument based largely on human development and education theory be developed that reliably discriminates high, moderate, and low quality in environmental education curricula? The types of analyses conducted to answer this question were interrater reliability (percent agreement, Cohen's Kappa coefficient, Pearson's Product-Moment correlation coefficient), test-retest reliability (percent agreement, correlation), and criterion-related validity (correlation). Face validity and content validity were also assessed through thorough reviews. Overall results indicate that 29% of the questions on the questionnaire demonstrated a high level of interrater reliability and 43% of the questions demonstrated a moderate level of interrater reliability. Seventy-one percent of the questions demonstrated a high test-retest reliability and 5% a moderate level. Fifty-five percent of the questions on the questionnaire were reliable (high or moderate) both across time and raters. Only eight questions (8%) did not show either interrater or test-retest reliability. The global overall rating of high, medium, or low quality was reliable across both coders and time, indicating that the questionnaire can discriminate differences in quality of environmental education curricula. Of the 35 curricula evaluated, 6 were high quality, 14 were medium quality and 15 were low quality. The criterion-related validity of the instrument is at current time unable to be established due to the lack of comparable measures or a concretely usable set of multidisciplinary standards. Face and content validity were sufficiently demonstrated.

Minner, Daphne Diane

176

Open-Source MFIX-DEM Software for Gas-Solids Flows: Part II - Validation Studies  

SciTech Connect

With rapid advancements in computer hardware and numerical algorithms, computational fluid dynamics (CFD) has been increasingly employed as a useful tool for investigating the complex hydrodynamics inherent in multiphase flows. An important step during the development of a CFD model and prior to its application is conducting careful and comprehensive verification and validation studies. Accordingly, efforts to verify and validate the open-source MFIX-DEM software, which can be used for simulating the gas–solids flow using an Eulerian reference frame for the continuum fluid and a Lagrangian discrete framework (Discrete Element Method) for the particles, have been made at the National Energy Technology Laboratory (NETL). In part I of this paper, extensive verification studies were presented and in this part, detailed validation studies of MFIX-DEM are presented. A series of test cases covering a range of gas–solids flow applications were conducted. In particular the numerical results for the random packing of a binary particle mixture, the repose angle of a sandpile formed during a side charge process, velocity, granular temperature, and voidage profiles from a bounded granular shear flow, lateral voidage and velocity profiles from a monodisperse bubbling fluidized bed, lateral velocity profiles from a spouted bed, and the dynamics of segregation of a binary mixture in a bubbling bed were compared with available experimental data, and in some instances with empirical correlations. In addition, sensitivity studies were conducted for various parameters to quantify the error in the numerical simulation.

Li, Tingwen

2012-04-01

177

Open-source MFIX-DEM software for gas-solids flows: Part II Validation studies  

SciTech Connect

With rapid advancements in computer hardware and numerical algorithms, computational fluid dynamics (CFD) has been increasingly employed as a useful tool for investigating the complex hydrodynamics inherent in multiphase flows. An important step during the development of a CFD model and prior to its application is conducting careful and comprehensive verification and validation studies. Accordingly, efforts to verify and validate the open-source MFIX-DEM software, which can be used for simulating the gas solids flow using an Eulerian reference frame for the continuum fluid and a Lagrangian discrete framework (Discrete Element Method) for the particles, have been made at the National Energy Technology Laboratory (NETL). In part I of this paper, extensive verification studies were presented and in this part, detailed validation studies of MFIX-DEM are presented. A series of test cases covering a range of gas solids flow applications were conducted. In particular the numerical results for the random packing of a binary particle mixture, the repose angle of a sandpile formed during a side charge process, velocity, granular temperature, and voidage profiles from a bounded granular shear flow, lateral voidage and velocity profiles from a monodisperse bubbling fluidized bed, lateral velocity profiles from a spouted bed, and the dynamics of segregation of a binary mixture in a bubbling bed were compared with available experimental data, and in some instances with empirical correlations. In addition, sensitivity studies were conducted for various parameters to quantify the error in the numerical simulation.

Li, Tingwen [National Energy Technology Laboratory (NETL); Garg, Rahul [National Energy Technology Laboratory (NETL); Galvin, Janine [National Energy Technology Laboratory (NETL); Pannala, Sreekanth [ORNL

2012-01-01

178

Temporal study of wake formation behind a conducting body  

SciTech Connect

The temporal evolution of the wake of a conducting body is studied experimentally in a pulsed plasma device. Three-dimensional measurements of the plasma potential, density, particle energy distribution, and ion currents are measured throughout the near- and mid-wake regions during the wake formation. It is found that the potential behind the conducting body is initially negative. This negative potential is caused by the higher mobility of the electrons, allowing them to flow into the ion free wake region. The negative potential in the wake region induces an electric field that pulls ions into the region behind the conducting body. However, the dominant factor in determining the length of the near wake is the thermal energy spread of the ions. At later times, as the sheath forms around the conducting body, ions are deflected by the potential gradient in the sheath region. This deflection, in addition to the thermal energy spread of the ions, determines the length of the near wake.

Meassick, S.; Chan, C.; Qian, Y.; Sroda, T.; Azar, T.; Allen, R.C. (Northeastern Univ., Boston, MA (USA))

1991-08-01

179

Structural study of semiconducting and superionic conducting silver vanadate glasses  

Microsoft Academic Search

A structural study of semiconducting and superionic conducting silver vanadate glasses, containing 40 mol% Agl and 1 mol %57Fe2O3, is performed by means of Mössbauer spectroscopy. Distinct composition dependency of Mössbauer parameters (? and G) of Fe3+ ions, having a minimum when Ag2O content is 30 mol %, suggests that increasing Ag2O content results in a gradual change of the

Tetsuaki Nishida; Hiroshi Ide; Yoshimasa Takashima; Toshirou Yagi; Satoru Tomariguchi; Tohru Ishizuka; Akira Sakai

1989-01-01

180

A validation study of the domains of the core EORTC Quality of Life Questionnaire  

Microsoft Academic Search

A cohort study was conducted to investigate the construct validity of the domains of the EORTC QLQ-C30 (European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire). Ninety-six patients undergoing chemotherapy at the Kingston Regional Cancer Centre, Kingston, Canada were given the EORTC QLQ-C30 and two out of four comparison scales; the Sickness Impact Profile, the McGill

H. E. Niezgoda; J. L. Pater

1993-01-01

181

STUDY OF LOSS EFFECT OF TRANSMISSION LINES AND VALIDITY OF A SPICE MODEL IN ELECTROMAGNETIC TOPOLOGY  

Microsoft Academic Search

Abstract—This paper studies the loss effect of the line and the validity of a SPICE model for lossless transmission lines excited by an incident plane wave by using a simple structure —a single line over an infinite perfectly conducting ground excited by an incident electromagnetic field. The frequency domain,current responses calculated by the Baum-Liu-Tesche (BLT) equation with the loss ignored

Haiyan Xie; Jianguo Wang; Ruyu Fan; Yinong Liu

2009-01-01

182

Studying Pretrial Publicity Effects: New Methods for Improving Ecological Validity and Testing External Validity  

Microsoft Academic Search

Although research examining the effects of pretrial publicity (PTP) on individuals' appraisals of a defendant and verdict decision making generally has been found to be internally valid, the external validity has been questioned by some social scientists as well as lawyers and judges. It is often proposed that the verisimilitude (or ecological validity) of the research should be increased in

Christina A. Studebaker; Jennifer K. Robbennolt; Steven D. Penrod; Maithilee K. Pathak-Sharma; Jennifer L. Groscup; Jennifer L. Devenport

2002-01-01

183

Validity and reliability of in-situ air conduction thresholds measured through hearing aids coupled to closed and open instant-fit tips.  

PubMed

Audiometric measurements through a hearing aid ('in-situ') may facilitate provision of hearing services where these are limited. This study investigated the validity and reliability of in-situ air conduction hearing thresholds measured with closed and open domes relative to thresholds measured with insert earphones, and explored sources of variability in the measures. Twenty-four adults with sensorineural hearing impairment attended two sessions in which thresholds and real-ear-to-dial-difference (REDD) values were measured. Without correction, significantly higher low-frequency thresholds in dB HL were measured in-situ than with insert earphones. Differences were due predominantly to differences in ear canal SPL, as measured with the REDD, which were attributed to leaking low-frequency energy. Test-retest data yielded higher variability with the closed dome coupling due to inconsistent seals achieved with this tip. For all three conditions, inter-participant variability in the REDD values was greater than intra-participant variability. Overall, in-situ audiometry is as valid and reliable as conventional audiometry provided appropriate REDD corrections are made and ambient sound in the test environment is controlled. PMID:20812890

O'Brien, Anna; Keidser, Gitte; Yeend, Ingrid; Hartley, Lisa; Dillon, Harvey

2010-09-03

184

Evaluating the quality of dietary intake validation studies.  

PubMed

Within the EURopean micronutrient RECommendations Aligned Network of Excellence (EURRECA), a scoring system was developed to assess the quality of dietary intake validation studies. The scoring system included three steps. The first step was to give each study a quality score, which included five components: sample size, statistics used, data collection procedure, consideration of seasonality and supplement use. Scores ranged from 0 to 7, and validation studies classified as very good ( > or = 5), good (5-3.5), acceptable/reasonable (3.5-2.5) and poor ( < 2.5). The second and third steps included an adjustment/weighting of the correlation coefficient according to the quality score and moreover a rating of the adjusted/weighted correlation. The scoring system was tested in 124 validation studies that included at least one vitamin. Only 5.6 % of the 124 studies were judged to be of very good quality according to the quality score, 41.9 % of good quality and 16.9 % had a poor rating. When adjusting for the study quality scores, crude and adjusted mean correlations of vitamins A, C, D and E intakes were similar, but the percentage of correlation values classified as poor or very good was higher after adjustment. These results show the importance of considering the quality of studies validating dietary assessment methods and the correlations obtained for the micronutrient of interest when interpreting effects observed in epidemiological studies using dietary assessment methods. Without a doubt, this subject constitutes a key topic for research in nutritional epidemiology. PMID:20100366

Serra-Majem, Lluis; Frost Andersen, Lene; Henríque-Sánchez, Patricia; Doreste-Alonso, Jorge; Sánchez-Villegas, Almudena; Ortiz-Andrelluchi, Adriana; Negri, Eva; La Vecchia, Carlo

2009-12-01

185

The Significance of Member Validation in Qualitative Analysis: Experiences from a Longitudinal Case Study  

Microsoft Academic Search

This article explores the concept of member validation and its potential role in the process of constructing case descriptions and interpretations in qualitative research. Although generally approved as a required step in qualitative inquiry, the format, conduct, and purpose of this vary significantly according to different research perspectives. The paper discusses methodological and validity aspects of member validation, and illustrates

Bendik Bygstad; Bjørn Erik Munkvold

2007-01-01

186

Steady-state hydraulic tomography in a laboratory aquifer with deterministic heterogeneity: Multi-method and multiscale validation of hydraulic conductivity tomograms  

Microsoft Academic Search

Hydraulic tomography potentially is a viable technology that facilitates subsurface imaging of hydraulic heterogeneity. To date, a comprehensive validation of hydraulic tomography has not been done either at the laboratory or field scales. The main objective of this paper is to examine the accuracy of hydraulic conductivity (K) tomograms obtained from the steady-state hydraulic tomography algorithm of [Yeh, T.-C. J.,

Walter A. Illman; Xiaoyi Liu; Andrew Craig

2007-01-01

187

Reliability and validity of self-assessment of mouth opening: a validation study  

PubMed Central

Background The objective of this study was to evaluate the reproducibility and validity of patients’ mouth opening measurements in a research setting. Methods Firstly, 68 patients made repeated self-measurements of mouth opening using a cardboard scale (Therabite Range of Motion Scale – TRMS). Secondly, 80 patients enrolled in a clinical trial on morbidity after lower third molar surgery, made daily assessments during the postoperative week. Patients’ measurements were then compared to gold-standard clinicians’ measurements. Results Reliability of patients’ measurements was excellent with an intraclass correlation coefficient of 0.92. The patient’s measurements correlated well with the gold-standard clinician’s measurements, both for the first 68 patients (Pearson’s rho ranging from 0.86 to 0.90, p < 0.0001) as well as for the 80 patients enrolled in the clinical trial (rho = 0.82, p < 0.0001 at day 2, rho = 0.83, p < 0.0001 at final visit). Conclusions TRMS can be used by patients to produce reproducible and valid mouth opening measurements.

2012-01-01

188

Obtaining Valid Laboratory Data in Clinical Trials Conducted in Resource Diverse Settings: Lessons Learned from a Microbicide Phase III Clinical Trial  

PubMed Central

Background Over the last decade several phase III microbicides trials have been conducted in developing countries. However, laboratories in resource constrained settings do not always have the experience, infrastructure, and the capacity to deliver laboratory data meeting the high standards of clinical trials. This paper describes the design and outcomes of a laboratory quality assurance program which was implemented during a phase III clinical trial evaluating the efficacy of the candidate microbicide Cellulose Sulfate 6% (CS) [1]. Methodology In order to assess the effectiveness of CS for HIV and STI prevention, a phase III clinical trial was conducted in 5 sites: 3 in Africa and 2 in India. The trial sponsor identified an International Central Reference Laboratory (ICRL), responsible for the design and management of a quality assurance program, which would guarantee the reliability of laboratory data. The ICRL provided advice on the tests, assessed local laboratories, organized trainings, conducted supervision visits, performed re-tests, and prepared control panels. Local laboratories were provided with control panels for HIV rapid tests and Chlamydia trachomatis/Neisseria gonorrhoeae (CT/NG) amplification technique. Aliquots from respective control panels were tested by local laboratories and were compared with results obtained at the ICRL. Results Overall, good results were observed. However, discordances between the ICRL and site laboratories were identified for HIV and CT/NG results. One particular site experienced difficulties with HIV rapid testing shortly after study initiation. At all sites, DNA contamination was identified as a cause of invalid CT/NG results. Both problems were timely detected and solved. Through immediate feedback, guidance and repeated training of laboratory staff, additional inaccuracies were prevented. Conclusions Quality control guidelines when applied in field laboratories ensured the reliability and validity of final study data. It is essential that sponsors provide adequate resources for implementation of such comprehensive technical assessment and monitoring systems. Trial Registration ClinicalTrials.gov NCT00153777 and Current Controlled Trials ISRCTN95638385

Crucitti, Tania; Fransen, Katrien; Maharaj, Rashika; Tenywa, Tom; Massinga Loembe, Marguerite; Murugavel, Kailapuri Gangatharan; Mendonca, Kevin; Abdellati, Said; Beelaert, Greet; Van Damme, Lut

2010-01-01

189

Field Studies for Validation of Urban Dispersion Models - Current Status and Research Needs  

NASA Astrophysics Data System (ADS)

Urban dispersion models are important tools in addressing consequences from potential releases of harmful airborne materials in urban areas. These models are used by emergency management, law enforcement, and intelligence personnel to effectively plan for and respond to potential terrorist attacks and accidents. Field studies are vitally important for improving and validating these urban dispersion models which are used to simulate contaminant dispersion in and around cities. Over the past decade, three major urban field studies have been designed and conducted in the United States. The primary objectives of these studies have been to advance the state-of-science of understanding and modeling atmospheric flows and dispersion in and around cities, and to provide field observation for validation of urban dispersion models. The three major field studies (Salt Lake City, October 2000; Oklahoma City, July 2003; and New York City, August 2005) were conducted in cities of different sizes, in different geographic regions and during different times of the year. The tracer and meteorological data from these three field campaigns provide a rich dataset for validation of urban dispersion models over a range of conditions. The status and uses of the three urban dispersion datasets will be summarized, followed by a discussion of the current observational gaps and research needs in characterizing specific urban dispersion processes, such as outdoor-indoor coupling and outdoor-subway coupling.

Allwine, J.

2007-12-01

190

Fit-for-purpose bioanalytical cross-validation for LC-MS/MS assays in clinical studies.  

PubMed

The paradigm shift of globalized research and conducting clinical studies at different geographic locations worldwide to access broader patient populations has resulted in increased need of correlating bioanalytical results generated in multiple laboratories, often across national borders. Cross-validations of bioanalytical methods are often implemented to assure the equivalency of the bioanalytical results is demonstrated. Regulatory agencies, such as the US FDA and European Medicines Agency, have included the requirement of cross-validations in their respective bioanalytical validation guidance and guidelines. While those documents provide high-level expectations, the detailed implementation is at the discretion of each individual organization. At Bristol-Myers Squibb, we practice a fit-for-purpose approach for conducting cross-validations for small-molecule bioanalytical methods using LC-MS/MS. A step-by-step proposal on the overall strategy, procedures and technical details for conducting a successful cross-validation is presented herein. A case study utilizing the proposed cross-validation approach to rule out method variability as the potential cause for high variance observed in PK studies is also presented. PMID:23256474

Xu, Xiaohui; Ji, Qin C; Jemal, Mohammed; Gleason, Carol; Shen, Jim X; Stouffer, Bruce; Arnold, Mark E

2013-01-01

191

Validation studies of the DOE-2 Building Energy Simulation Program. Final Report  

SciTech Connect

This report documents many of the validation studies (Table 1) of the DOE-2 building energy analysis simulation program that have taken place since 1981. Results for several versions of the program are presented with the most recent study conducted in 1996 on version DOE-2.1E and the most distant study conducted in 1981 on version DOE-1.3. This work is part of an effort related to continued development of DOE-2, particularly in its use as a simulation engine for new specialized versions of the program such as the recently released RESFEN 3.1. RESFEN 3.1 is a program specifically dealing with analyzing the energy performance of windows in residential buildings. The intent in providing the results of these validation studies is to give potential users of the program a high degree of confidence in the calculated results. Validation studies in which calculated simulation data is compared to measured data have been conducted throughout the development of the DOE-2 program. Discrepancies discovered during the course of such work has resulted in improvements in the simulation algorithms. Table 2 provides a listing of additions and modifications that have been made to various versions of the program since version DOE-2.1A. One of the most significant recent changes in the program occurred with version DOE-2.1E. An improved algorithm for calculating the outside surface film coefficient was implemented. In addition, integration of the WINDOW 4 program was accomplished resulting in improved ability in analyzing window energy performance. Validation and verification of a program as sophisticated as DOE-2 must necessarily be limited because of the approximations inherent in the program. For example, the most accurate model of the heat transfer processes in a building would include a three-dimensional analysis. To justify such detailed algorithmic procedures would correspondingly require detailed information describing the building and/or HVAC system and energy plant parameters. Until building simulation programs can get this data directly from CAD programs, such detail would negate the usefulness of the program for the practicing engineers and architects who currently use the program. In addition, the validation studies discussed herein indicate that such detail is really unnecessary. The comparison of calculated and measured quantities have resulted in a satisfactory level of confidence that is sufficient for continued use of the DOE-2 program. However, additional validation is warranted, particularly at the component level, to further improve the program.

Sullivan, R.; Winkelmann, F.

1998-06-01

192

Study on the non-fourier heat conduction.  

National Technical Information Service (NTIS)

Heat conduction problem in many engineering situations has been analyzed by using the heat conduction equation based on the classical Fourier model. However, Fourier's law implies that any thermal disturbances on a body is instantaneously felt throughout ...

K. Woo-Seung

1994-01-01

193

Studies on the Preparation of Polystyrene Thermal Conductivity Composites  

Microsoft Academic Search

Various thermally conductive fillers including aluminum oxide(Al2O3), magnesium oxide(MgO), ?-silicon carbide particle(?-SiCp) and ?-silicon carbide whisker(?-SiCw) were used to prepare polystyrene thermal conductivity composites. Experimental results showed that, for given filler loading, the thermal conductivity of the composites was higher for PS flake than that of PS particle, and the thermal conductivity was optimal by powder blending method. The SiCw

Jun-Wei Gu; Qiuyu Zhang; Junping Zhang; Wenwen Wang

2010-01-01

194

Task Analysis in the Design of Three Concurrent Validity Studies of the Professional and Administrative Career Examination.  

ERIC Educational Resources Information Center

The U.S. Civil Service Commission conducted three criterion-related validity studies for its PACE Test. Three occupations were examined using a specially designed supervisory rating form, job information test, and work sample. A computer analyzed task inventory was the keystone of the study. (Editor/SJL)

Trattner, Marvin H.

1979-01-01

195

Studies of electrical conduction in pyroelectric DTGS: PVDF composites  

NASA Astrophysics Data System (ADS)

The AC and DC conductivities of pyroelectric composite, deuterated triglycine sulfate (DTGS): polyvinylidene fluoride (PVDF) having 15%, 20%, and 40% DTGS content (by weight) have been measured at temperature ranging from room temperature to 55 °C. The ac conductivity of composites at 1 MHz shows very weak temperature dependence. The dc conductivity for 20% and 40% DTGS content (by weight) composites shows activated behavior.

Batra, Ashok K.; Simmons, M.; Guggilla, Padmaja; Aggarwal, M. D.; Lal, R. B.

2004-06-01

196

Thermal conductivity at the nanoscale: A molecular dynamics study  

NASA Astrophysics Data System (ADS)

With the growing use of nanotechnology and nanodevices in many fields of engineering and science, a need for understanding the thermal properties of such devices has increased. The ability for nanomaterials to conduct heat is highly dependent on the purity of the material, internal boundaries due to material changes and the structure of the material itself. Experimentally measuring the heat transport at the nanoscale is extremely difficult and can only be done as a macro output from the device. Computational methods such as various Monte Carlo (MC) and molecular dynamics (MD) techniques for studying the contribution of atomic vibrations associated with heat transport properties are very useful. The Green--Kubo method in conjunction with Fourier's law for calculating the thermal conductivity, kappa, has been used in this study and has shown promise as one approach well adapted for understanding nanosystems. Investigations were made of the thermal conductivity using noble gases, modeled with Lennard-Jones (LJ) interactions, in solid face-centered cubic (FCC) structures. MC and MD simulations were done to study homogeneous monatomic and binary materials as well as slabs of these materials possessing internal boundaries. Additionally, MD simulations were done on silicon carbide nanowires, nanotubes, and nanofilaments using a potential containing two-body and three-body terms. The results of the MC and MD simulations were matched against available experimental and other simulations and showed that both methods can accurately simulate real materials in a fraction of the time and effort. The results of the study show that in compositionally disordered materials the selection of atomic components by their mass, hard-core atomic diameter, well depth, and relative concentration can change the kappa by as much as an order of magnitude. It was found that a 60% increase in mass produces a 25% decrease in kappa. A 50% increase in interatomic strength produces a 25% increase in kappa, while as little as a 10% change in the hard core radius can almost totally suppress a materials ability to conduct heat. Additionally, for two LJ materials sharing an interface, the atomic vibrations altering the heat energy depend on the type of internal boundary in the material. Mass increases across the interfacial boundary enhance excitation of the very low frequency (ballistic) vibrational modes, while the opposite effect is seen as increases in hard core radius and interatomic strength enhance excitation of higher frequency vibrational modes. Additionally, it was found that this effect was diminished for higher temperatures around half the Debye temperatures. In nanodevices and nanomachines, there is an additional factor that degrades heat transport at the boundary. In fact, the interface induces a temperature jump consistent with a thermal resistance created by the boundary. It was found that the temperature jump, which is due to a boundary resistance, was significant in boundaries involving small mass changes, lesser in changes in hard core radii changes and even lesser for interatomic strength changes. The study of SiC nanowires and nanotubes showed that the structural changes produced vastly different kappa. The kappa in closely packed structures like nanowires and nanofilaments approximated that of the bulk SiC, yet were less sensitive to temperature than the 1/T relationship traditionally found in bulk systems. The more open nanostructures, like nanotubes, had vastly lower kappa values and are almost totally insensitive to temperature variation. The results of this study can be used in the design of nano-machines where heat generation and transport is a concern. Additionally, the design of nano-machines which transport heat like nano-refrigerators or nano-heaters may be possible due to a better selection of materials with the understanding of how the materials affect their nanothermal properties at the nano scale.

Lyver, John W., IV

197

Spectroscopic and Electrical Conductivity Studies of Some Semicarbazide Hydrochloride Complexes  

NASA Astrophysics Data System (ADS)

The infrared and electronic absorption spectra of semicarbazide hydrochloride and its complexes with anthracene, tetracyanoquinodimethane TCNQ, Na-fluorescein and cupferron were recorded in the regions 200-4000cm-1 and 200-400nm. The new bands that appeared in the complex spectra were assigned. The effect of the complex formation on the frequency and intensity of the active vibrational bands was also studied. The internal energy changes of the complexes were calculated in a new line of calculation to give a clear insight about the stability of the investigated complexes. The electrical conductivity of the complexes was measured in the temperature range 25-130°C. The activation energy E was calculated and discussed on the basis of the spectroscopic information.

Fadly, M.; El-Manakhly, H.

1998-11-01

198

A procedure for the measurement of infant skin conductance and its initial validation using clap induced startle  

PubMed Central

Studies examining psychophysiologic markers of infant emotional development abound. However, few studies have used skin conductance (SC), though it measures sympathetic activity, and none have measured SC on infants sitting up and actively engaged with another person, a significant challenge given the measures sensitivity to movement artifact. In this pilot/feasibility study, we present a procedure for measuring infant SC during active engagement with another person who executes a series of startling claps to elicit an SC response. We measured SC on the plantar surface of the foot of 17 five-month old infants. We found unconditioned SC responses that were related to the intensity of physical startle reactions for each clap trial. We also found anticipatory, conditioned SC responses that occurred within 5s before each clap that occurred when the researcher raised his clasped hands. These conditioned SC responses grew linearly in intensity over trials. We conclude that SC may be a useful addition to the infant researcher’s armamentarium and may indeed be used to measure physiologic reactivity in infants even when actively engaged with another person. Addition of SC measurement to research on infant emotion and emotional communication is likely to advance our understanding of the psychophysiologic foundations of infant emotional development.

Ham, Jacob; Tronick, Ed

2008-01-01

199

A procedure for the measurement of infant skin conductance and its initial validation using clap induced startle.  

PubMed

Studies examining psychophysiologic markers of infant emotional development abound. However, few studies have used skin conductance (SC), though it measure's sympathetic activity, and none have measured SC on infants sitting up and actively engaged with another person, a significant challenge given the measures sensitivity to movement artifact. In this pilot/feasibility study, we present a procedure for measuring infant SC during active engagement with another person who executes a series of startling claps to elicit an SC response. We measured SC on the plantar surface of the foot of seventeen 5-month-old infants. We found unconditioned SC responses that were related to the intensity of physical startle reactions for each clap trial. We also found anticipatory, conditioned SC responses that occurred within 5 s before each clap that occurred when the researcher raised his clasped hands. These conditioned SC responses grew linearly in intensity over trials. We conclude that SC may be a useful addition to the infant researcher's armamentarium and may indeed be used to measure physiologic reactivity in infants even when actively engaged with another person. Addition of SC measurement to research on infant emotion and emotional communication is likely to advance our understanding of the psychophysiologic foundations of infant emotional development. PMID:18683186

Ham, Jacob; Tronick, Ed

2008-09-01

200

Validation studies performed with mixed Pu + U aqueous critical experiments in annual geometry  

SciTech Connect

This paper discusses the results of a calculational study that was performed to validate the SCALE computer code system using data from critical experiments performed with mixed Pu + U agueous solutions. The critical experiments were conducted in an annular vessel where the fissile solution was placed in the annulus, and various inserts and bottles containing fissile solution were located in the inner portion of the vessel. These experimental activities are part of a joint exchange program between the US Department of Energy and the Power Reactor and Nuclear Fuel Development Corporation of Japan in the area of criticality data development. The experiments were conducted at the Battelle Pacific Northwest Laboratory's Critical Mass Laboratory (CML). In summary, calculated multiplication factors have been examined for 18 critical experiments conducted in annular geometry with mixed Pu + U solutions. The results indicate that the SCALE computer code system with CSRL cross sections is capable of accurately modeling mixed fissile systems in annular geometry.

Smolen, G.R.; Yamana, H. (Oak Ridge National Lab., TN (USA))

1988-01-01

201

Total-body electrical conductivity method for estimating body composition: validation by direct carcass analysis of pigs14  

Microsoft Academic Search

Determination of body composition by measuring total-body electrical con- ductivity (TOBEC) is based on the principle that body fat and fat-free mass (FFM) differ in electrical properties. In humans, we are able to estimate body composition only by indirect methods, which have been used to validate the TOBEC instrument. Relationships between TOBEC and body composition were examined using direct carcass

Nancy L Keim; Patrick L Mayclin; Scott J Taylor; Dan L Brown

202

21 CFR 58.130 - Conduct of a nonclinical laboratory study.  

Code of Federal Regulations, 2013 CFR

...false Conduct of a nonclinical laboratory study. 58.130 Section 58.130 Food...LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Protocol for and Conduct of a Nonclinical Laboratory Study § 58.130 Conduct of a...

2013-04-01

203

Case study for model validation : assessing a model for thermal decomposition of polyurethane foam.  

SciTech Connect

A case study is reported to document the details of a validation process to assess the accuracy of a mathematical model to represent experiments involving thermal decomposition of polyurethane foam. The focus of the report is to work through a validation process. The process addresses the following activities. The intended application of mathematical model is discussed to better understand the pertinent parameter space. The parameter space of the validation experiments is mapped to the application parameter space. The mathematical models, computer code to solve the models and its (code) verification are presented. Experimental data from two activities are used to validate mathematical models. The first experiment assesses the chemistry model alone and the second experiment assesses the model of coupled chemistry, conduction, and enclosure radiation. The model results of both experimental activities are summarized and uncertainty of the model to represent each experimental activity is estimated. The comparison between the experiment data and model results is quantified with various metrics. After addressing these activities, an assessment of the process for the case study is given. Weaknesses in the process are discussed and lessons learned are summarized.

Dowding, Kevin J.; Leslie, Ian H. (New Mexico State University, Las Cruces, NM); Hobbs, Michael L.; Rutherford, Brian Milne; Hills, Richard Guy (New Mexico State University, Las Cruces, NM); Pilch, Martin M.

2004-10-01

204

Photoluminescence and conductivity studies of anthracene-functionalized ruthenium nanoparticles.  

PubMed

Carbene-stabilized ruthenium nanoparticles were functionalized with anthryl moieties by olefin metathesis reactions with 9-vinylanthracene, at a surface concentration of about 19.7%, as estimated by (1)H NMR spectroscopic measurements. Because of the conjugated metal-ligand interfacial bonding interactions, UV-vis measurements of the resulting nanoparticles showed a new broad absorption band centered at 612 nm, in addition to the peaks observed with monomeric vinylanthracene. FTIR measurements depicted apparent red-shifts of the aromatic vibrational stretches as compared to those of the monomeric vinylanthracene, suggestive of decreasing bonding order of the aromatic moieties as a result of extended conjugation between the particle-bound anthracene groups. Photoluminescence measurements confirmed the notion that effective intraparticle charge delocalization occurred by virtue of the conjugated metal-ligand interfacial bonding interactions, with apparent red-shifts of the excitation peaks and blue-shifts of the emission features, as compared to those of the monomeric vinylanthracene. The diminishment of the Stokes shift was, at least in part, attributed to the different chemical environments surrounding the anthryl moieties on the nanoparticle surface. Electronic conductivity measurements showed that because of the conjugated Ru[double bond, length as m-dash]C ? bonds, the activation energy for interparticle charge transport was about one order of magnitude lower than that observed with particles passivated by alkanethiolates. Additionally, whereas the original carbene-stabilized nanoparticles exhibited a semiconductor-metal transition within the temperature range of 100 to 320 K, anthracene-functionalized nanoparticles displayed apparent semiconducting behaviors with the ensemble conductivity increasing monotonically with temperature, most likely due to the disordering within the nanoparticle solids that arose from the different structures of the carbene ligands and anthryl moieties. These studies indicate that anthracene functionalization may be exploited as an effective route towards the manipulation of nanoparticle optoelectronic properties. PMID:21494751

Chen, Wei; Pradhan, Sulolit; Chen, Shaowei

2011-04-15

205

ICESat Calibration-Validation and Mass Balance Studies in Antarctica  

NASA Astrophysics Data System (ADS)

To map mass balance changes of major drainage basins over a relatively short period, ICESat is designed to measure surface elevation changes with an accuracy of 1.5 cm/year for spatial averages of measurements over areas of 100 km2. To achieve this accuracy different post-launch calibration-validation (CV) approaches are used to identify and to remove the non-geophysical artifacts from the data products. As part of the CV effort detailed surface topography was mapped by NASA's Airborne Topographic Mapper (ATM) scanning laser over sites in Greenland, western US and the Dry Valleys in Antarctica. Ice sheet surface elevations mapped by airborne laser altimetry surveys also serve as baselines for the ICESat mission. Here we present results from two different projects in the Antarctica. Detailed surface topography, derived from ATM data, is used to verify the ICESat products over the Dry Valleys. Surface elevations, mapped by the University of Texas airborne system (former Support Office of Airborne Geophysics), serves as baselines to map changes over the West Antarctic Ice Sheet ice streams. ATM surveys were conducted over the Dry Valleys in December 2001 in collaboration with NSF and USGS. In addition to survey candidate calibration/validation sites for the ICESat mission, the campaign was going to support NSF projects and to provide data to evaluate the potential of the use of laser altimetry in the Antarctica. The survey resulted blanket coverage over several sites. We have developed a procedure using robust estimation techniques to remove the outlier observations and to interpolate the data into regular grids (DEMs). The ICESat elevation and waveform products were verified by comparing them with the DEMs and with simulated waveforms. Surface reflectivity, necessary for the waveform simulation, was derived from satellite imagery. The stable terrain of the site makes it ideal for serving as benchmark surface throughout the ICESat mission. Precise repeat laser altimetry surveys were conducted with the SOAR system in 1997/98 and 1999/2000 over portions of the Whillans ice stream and ice streams C and E, West Antarctica. It is well known that these ice streams are undergoing substantial changes in length, width, thickness and speed at decadal and shorter changes. We determined elevation changes during the last 5 years by comparing elevations measured by ICESat over the 8-day repeat orbits with the results of the SOAR surveys. We plan to use the 91-day repeat ICESat data to investigate the details of the surface change pattern.

Csatho, B.; Schenk, T.; Huh, K.; van der Veen, C.; Lee, I.; Spikes, V. B.; Krabill, W.

2003-12-01

206

Electrical Conductivity and Dielectric Studies of Hydraulic Cements  

NASA Astrophysics Data System (ADS)

Electrical properties of portland cements and other non-portland cementitious materials have been studied at two different stages of hydration. The following relationships have been observed:. Higher water/cement (w/c) ratio (0.5 compared to 0.4) resulted in an increase of the relative permittivity and electrical conductivity of early stage hydrating materials. The relative permittivity values were close to 10('7). The phenomena giving rise to changes in electrical conductivity have been related to the heat of hydration. Higher alkali ion concentration resulted in higher electrical conductivity and relative permittivity values in cement pastes. Cations of inorganic admixtures were found to increase maximum peak of electrical conductivity and relative permittivity in the order: Ca('++) > Mg('++) > Sr('++) and K('+) (TURNEQ) Na('+) > Li('+). Dielectric properties of pressed hardened materials cured over water for 1 day with w/c = 0.20 and heat treated to 500(DEGREES)C prepared with type I, type III, and a microfine calcium silicate (MC500) cement have been compared as a function of temperature and frequency. The relative permittivity for type I hardened materials at 30(DEGREES)C was found to range from 12.5 to 9.4 at frequencies from 1 KHz to 2 MHz. The dissipation factor was found to range from 0.122 to 0.014. The relative permittivity and dissipation factors for type III hardened materials were found to range from 17.8 to 13.0 and from 0.035 to 0.071, respectively, and for MC500 hardened materials were determined to range from 7.6 to 6.9 and from 0.033 to 0.002, respectively. The activation energies determined from Arrhenius plots for the relaxation mechanism operating in these materials correspond to 0.33, 0.30, and 0.46 eV for type I, type III, and MC500 densified hardened materials, respectively. Cement/polymer composites have been prepared using 1.76 wt.% methyl cellulose polymer and a w/c ratio of 0.17. The relative permittivity and loss factor the samples cured over water range from 7.5 to 7.3 and from 0.001 to 0.005, respectively, at frequencies from 10 KHz to 1 MHz, while for the materials cured under sealed conditions, the values range from 5.6 to 5.4 and from 0.007 to 0.004. The heat-treated hardened MC500 cement based materials containing 60 vol.% silica microspheres have the lowest relative permittivity when compared to other materials prepared. The relative permittivity and loss factor of these materials ranged from 5.4 to 5.1 and from 0.035 to 0.012.

Pena, Marianela Perez

207

Study on Voice Recognition Utilizing Bone-Conducted Voice  

Microsoft Academic Search

Voice recognition utilizing bone-conducted voice, which is very robust under noisy environment, has been investigated. The suitability for voice recognition and voice communication of bone-conducted voice recorded at several measurement points on human head was evaluated using LPC cepstrum distance (LCD) and Speech Transmission Index (STI). Experimental results show that forehead and cheek are good as the acquisition points of

Yoshiyasu Yamada; Yoshimasa Hijikata; Nobuaki Kawahara; Yoichi Fujisaka; Seiji Nakagawa

2004-01-01

208

Concurrent Validity of a Stress-Vulnerability Model of Suicidal Ideation and Behavior: A Follow-Up Study.  

ERIC Educational Resources Information Center

|Conducted follow-up study to test concurrent validity of stress-vulnerability model of suicidal ideation and behavior. College students (N=202) completed self-report measures of life stress, loneliness, depression, dysfunctional cognitions, reasons for living, hopelessness, current suicide ideation, and predictions of future suicide probability.…

Rich, Alexander; Bonner, Ronald L.

1987-01-01

209

Validating the Response Process of the Spanish Version of the Short Sensory Profile: A Pilot Study Using Cognitive Interviews  

Microsoft Academic Search

The Short Sensory Profile (SSP) is one of the only sensory processing tools available in Spanish, making it viable for use with a Puerto Rican population. The Spanish version of this tool was translated using standard back-translation, but there have been no published studies conducted with the Spanish Short Sensory Profile (S-SSP) to verify reliability and validity. The purpose of

Rosa Román-Oyola; Stacey E. Reynolds

2010-01-01

210

Genome-wide association study of conduct disorder symptomatology  

PubMed Central

Conduct disorder (CD) is one of the most prevalent childhood psychiatric conditions, and is associated with a number of serious concomitant and future problems. CD symptomatology is known to have a considerable genetic component, with heritability estimates in the range of 50%. Despite this, there is a relative paucity of studies aimed at identifying genes involved in the susceptibility to CD. In this study, we report results from a genome-wide association study of CD symptoms. CD symptoms were retrospectively reported by a psychiatric interview among a sample of cases and controls, in which cases met the criteria for alcohol dependence. Our primary phenotype was the natural log transformation of the number of CD symptoms that were endorsed, with data available for 3963 individuals who were genotyped on the Illumina Human 1M beadchip array. Secondary analyses are presented for case versus control status, in which caseness was established as endorsing three or more CD symptoms (N= 872 with CD and N= 3091 without CD). We find four markers that meet the criteria for genome-wide significance (P < 5 × 10?8) with the CD symptom count, two of which are located in the gene C1QTNF7 (C1q and tumor necrosis factor-related protein 7). There were six additional SNPs in the gene that yielded converging evidence of association. These data provide the first evidence of a specific gene that is associated with CD symptomatology. None of the top signals resided in traditional candidate genes, underscoring the importance of a genome-wide approach for identifying novel variants involved in this serious childhood disorder.

Dick, DM; Aliev, F; Krueger, RF; Edwards, A; Agrawal, A; Lynskey, M; Lin, P; Schuckit, M; Hesselbrock, V; Nurnberger, J; Almasy, L; Porjesz, B; Edenberg, HJ; Bucholz, K; Kramer, J; Kuperman, S; Bierut, L

2013-01-01

211

Perovskite transparent conducting oxides: an ab initio study.  

PubMed

We present an ab initio study of the electronic structure and of the formation energies of various point defects in BaSnO3 and SrGeO3. We show that La and Y impurities substituting Ba or Sr are shallow donors with a preferred 1 +  charge state. These defects have a low formation energy within all the suitable equilibrium growth conditions considered. Oxygen vacancies behave as shallow donors as well, preferring the 2 +  charge state. Their formation energies, however, are higher in most growth conditions, indicating a limited contribution to conductivity. The calculated electron effective mass in BaSnO3, with a value of 0.21 me, and the very high mobility reported recently in La-doped BaSnO3 single-crystals, suggest that remarkably low scattering rates can be achieved in the latter. In the case of SrGeO3, our results point to carrier density and mobility values in the low range for typical polycrystalline TCOs, in line with experiment. PMID:24060940

Dabaghmanesh, S; Saniz, R; Amini, M N; Lamoen, D; Partoens, B

2013-09-24

212

Evolution of approaches in conducting total diet studies.  

PubMed

One of the main routes of human exposure to contaminants is through food. To assess the health impact, it is necessary to determine the levels of contaminants in foods and evaluate the exposure estimates. Many countries regularly conduct total diet studies as a method of assessing the exposure of the population to various contaminants present in foods. It is a comprehensive approach and is based on determination of contaminants in foods. The risk assessment is done by taking into account the actual quantity consumed by specific age-sex groups of a population. The approach has developed through multiple changes since its inception. This article aims to review and summarize the changes that have occurred in different countries. Some of the attempts include the addition of analytes and the use of sophisticated instrumentation in conjunction with better extraction and types of food commodities. The present analytical methods have reduced the limits of detection for many analytes in many food matrices, making this approach much more accurate and sensitive. PMID:22430944

Betsy, A; Sudershan Rao, V; Polasa, K

2012-03-19

213

Perovskite transparent conducting oxides: an ab initio study  

NASA Astrophysics Data System (ADS)

We present an ab initio study of the electronic structure and of the formation energies of various point defects in BaSnO3 and SrGeO3. We show that La and Y impurities substituting Ba or Sr are shallow donors with a preferred 1 + charge state. These defects have a low formation energy within all the suitable equilibrium growth conditions considered. Oxygen vacancies behave as shallow donors as well, preferring the 2 + charge state. Their formation energies, however, are higher in most growth conditions, indicating a limited contribution to conductivity. The calculated electron effective mass in BaSnO3, with a value of 0.21 me, and the very high mobility reported recently in La-doped BaSnO3 single-crystals, suggest that remarkably low scattering rates can be achieved in the latter. In the case of SrGeO3, our results point to carrier density and mobility values in the low range for typical polycrystalline TCOs, in line with experiment.

Dabaghmanesh, S.; Saniz, R.; Amini, M. N.; Lamoen, D.; Partoens, B.

2013-10-01

214

GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: CHEMICAL DEHALOGENATION (QUICK REFERENCE FACT SHEET)  

EPA Science Inventory

Systematically conducted, well-documented treatability studies are an important component of remedy evaluation and selection under the Superfund program. his manual focuses on chemical dehalogenation treatability studies conducted in support of remedy selection that is conducted ...

215

Conductance through Quantum Dots Studied by Finite Temperature DMRG  

NASA Astrophysics Data System (ADS)

With the finite temperature density matrix renormalization group method (FT-DMRG), we have developed a method to calculate thermodynamic quantities and the conductance of a quantum dot system. Conductance is written by the local density of states at the dot. The density of states is calculated with the numerical analytic continuation from the thermal Green’s function which is obtained directly by the FT-DMRG. Typical Kondo behaviors in the quantum dot system are investigated clearly by comparing the conductance with the magnetic and charge susceptibilities: Coulomb oscillation peaks and the unitarity limit. We also discuss the advantage and disadvantage of the present method.

Maruyama, Isao; Shibata, Naokazu; Ueda, Kazuo

2004-02-01

216

Studying conduction-electron/interface interactions using transverse electron focusing  

NASA Astrophysics Data System (ADS)

Understanding the microscopic processes by which the electrons within conductors are scattered at surfaces and interfaces is important for both fundamental physics and technology. The authors review what has been learned so far about scattering of electrons at a variety of surfaces and interfaces using a technique, transverse electron focusing (TEF), that involves two point contacts in a uniform magnetic field. Transverse electron focusing is a sort of ?-ray spectrometer in a metal, except that, whereas the ?-ray spectrometer requires a narrow beam because the energy and momentum of a free electron can be arbitrary, in TEF the electrons of interest all have the Fermi energy and momentum, so focusing occurs even for electrons injected isotropically in angle. Transverse electron focusing is unique in its ability to probe localized and selectable portions of the interface from inside the conductor, using conduction electrons on only small parts of the Fermi surface. The authors first briefly review the essential features of TEF and of ideal and rough surfaces and describe the three techniques now used for injecting and detecting electrons: needle contacts, lithographically fabricated contacts, and light-induced injection. They then turn to measurements in metals and semimetals of the probability of specular reflection q from a given interface for electrons at the Fermi energy impinging at perpendicular incidence. They examine how q varies over different crystal faces for different electron orbits on the Fermi surfaces of a variety of conductors and how it is affected by changes in the de Broglie wavelength ?dB, by chemical etching, ion etching, or physical damage, by a molecular overlayer condensed from the surrounding atmosphere, and, for semimetals, by surface band bending (surface charge). The authors also explain how to measure the dependence of q upon the angle of incidence q(?), which gives information about surface structure. Transverse electron focusing studies of a variety of quasiparticle effects arising because the electrons are in a solid are described. These include (a) scattering of excitations moving on ``holelike'' orbits-q can depend upon the sign of the particle charge; (b) scattering involving a surface reciprocal-lattice vector G?, including surface resonances induced by an artificial grating etched onto a Bi surface; and (c) scattering between different parts of the Fermi surface-intervalley scattering (IVS)-including scattering in which the sign of the quasiparticle charge changes. The authors review studies of scattering of electrons from a normal-metal (or semimetal)/superconductor interface, which involves an unusual phenomenon called Andreev reflection, in which the signs of both the charge and mass change. Also described are TEF studies of scattering of light-excited electrons from an intercrystalline boundary and recent TEF measurements of q for scattering from the boundary of the two-dimensional electron gas. The authors conclude with a list of future TEF studies of conduction-electron/interface interactions that they believe to be interesting and important.

Tsoi, V. S.; Bass, J.; Wyder, P.

1999-10-01

217

Cross-cultural, age and gender validation of a computerised questionnaire measuring personal, social and environmental associations with children's physical activity: the European Youth Heart Study  

Microsoft Academic Search

OBJECTIVE: This study investigated the construct validity of a computerised self-assessment tool to measure psychological, social and environmental influences of young peoples' physical activity. First, analyses of the measure's factorial validity, invariance across, age, gender culture were conducted. Second, the ability of the derived subscales to discriminate between children representing different levels of self-reported and objectively measured physical activity behaviour

Yngvar Ommundsen; Angie Page; Po-Wen Ku; Ashley R Cooper

2008-01-01

218

Lamb wave Shearwave dispersion ultrasound Vibrometry (SDUV) validation study.  

PubMed

Our group has been investigating the use of Shearwave Dispersion Ultrasound Vibrometry (SDUV) for quantifying viscoelasticity of the myocardium. The primary aim of this study is the design and testing of viscoelastic materials suitable for validation of the Lamb wave model in the heart. The Lamb wave SDUV method was used to measure shear wave velocity dispersion of gelatin and urethane rubber plates in the range 40-500 Hz and estimate the material properties. A finite element model (FEM) of a viscoelastic plate submerged in water was used to study the appropriateness of the Lamb wave dispersion equations. An embedded sphere method was used as an independent measurement of viscoelasticity. The FEM wave velocity dispersion data were in excellent agreement with the theoretical predictions. Elasticity and viscosity of urethane and gelatin obtained using the Lamb wave SDUV and embedded sphere methods agree within one standard deviation. PMID:21095878

Nenadic, Ivan; Urban, Matthew W; Mitchell, Scott A; Greenleaf, James F

2010-01-01

219

Exploratory study of the thermal conductivity of methane hydrate  

Microsoft Academic Search

Recent discoveries of natural gas hydrates in permafrost and sub-oceanic environments have led us to measure the thermal conductivity of methane hydrate. A guarded hot-plate cell was constructed and tested with various ice specimens. We find the conductivity of methane hydrate near -60°C is 0.45 W\\/mk, a value close to that obtained for other clathrate hydrates by us and others.

J. G. Cook; D. G. Leaist

1983-01-01

220

Validation Studies of the The MONICA Optional Study of Physical Activity (MOSPA-Q)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

221

Water balance at an arid site: a model validation study of bare soil evaluation  

SciTech Connect

This report contains results of model validation studies conducted by Pacific Northwest Laboratory (PNL) for the Department of Energy's (DOE) National Low Level Waste Management Program (NLLWMP). The model validation tests consisted of using unsaturated water flow models to simulate water balance experiments conducted at the Buried Waste Test Facility (BWTF) located at the Department of Energy's Hanford site, near Richland, Washington. The BWTF is a lysimeter facility designed to collect field data on long-term water balance and radionuclide tracer movement. It has been operated by PNL for the NLLWMP since 1978. An experimental test case, developed from data collected at the BWTF, was used to evaluate predictions from different water flow models. The major focus of the validation study was to evaluate how the use of different evaporation models affected the accuracy of predictions of evaporation, storage, and drainage made by the whole model. Four evaporation models were tested including two empirical models and two mechanistic models. The empirical models estimate actual evaporation from potential evaporation; the mechanistic models describe water vapor diffusion within the soil profile and between the soil and the atmosphere in terms of fundamental soil properties, and transport processes. The water flow models that included the diffusion-type evaporation submodels performed best overall. The empirical models performed poorly in their description of evaporation and profile water storage during summer months. The predictions of drainage were supported quite well by the experimental data. This indicates that the method used to estimate hydraulic conductivity needed for the Darcian submodel was adequate. This important result supports recommendations for these procedures that were made previously based on laboratory results.

Jones, T.L.; Campbell, G.S.; Gee, G.W.

1984-03-01

222

A validation study of a stochastic model of human interaction  

NASA Astrophysics Data System (ADS)

The purpose of this dissertation is to validate a stochastic model of human interactions which is part of a developmentalism paradigm. Incorporating elements of ancient and contemporary philosophy and science, developmentalism defines human development as a progression of increasing competence and utilizes compatible theories of developmental psychology, cognitive psychology, educational psychology, social psychology, curriculum development, neurology, psychophysics, and physics. To validate a stochastic model of human interactions, the study addressed four research questions: (a) Does attitude vary over time? (b) What are the distributional assumptions underlying attitudes? (c) Does the stochastic model, {-}N{intlimitssbsp{-infty}{infty}}varphi(chi,tau)\\ Psi(tau)dtau, have utility for the study of attitudinal distributions and dynamics? (d) Are the Maxwell-Boltzmann, Fermi-Dirac, and Bose-Einstein theories applicable to human groups? Approximately 25,000 attitude observations were made using the Semantic Differential Scale. Positions of individuals varied over time and the logistic model predicted observed distributions with correlations between 0.98 and 1.0, with estimated standard errors significantly less than the magnitudes of the parameters. The results bring into question the applicability of Fisherian research designs (Fisher, 1922, 1928, 1938) for behavioral research based on the apparent failure of two fundamental assumptions-the noninteractive nature of the objects being studied and normal distribution of attributes. The findings indicate that individual belief structures are representable in terms of a psychological space which has the same or similar properties as physical space. The psychological space not only has dimension, but individuals interact by force equations similar to those described in theoretical physics models. Nonlinear regression techniques were used to estimate Fermi-Dirac parameters from the data. The model explained a high degree of the variance in each probability distribution. The correlation between predicted and observed probabilities ranged from a low of 0.955 to a high value of 0.998, indicating that humans behave in psychological space as Fermions behave in momentum space.

Burchfield, Mitchel Talmadge

223

Nerve conduction studies in upper extremities: skin temperature corrections.  

PubMed

The relationship of skin to near nerve (NN) temperature and to nerve conduction velocity (NCV) and distal latency (DL) was studied in 34 normal adult subjects before and after cooling both upper extremities. Median and ulnar motor and sensory NCV, DL, and NN temperature were determined at ambient temperature (mean X skin temp = 33 C) and after cooling, at approximately 26, 28, and 30 C of forearm skin temperature. Skin temperatures on the volar side of the forearm, wrist, palm, and fingers and NN temperature at the forearm, midpalm, and thenar or hypothenar eminence were compared with respective NCV and DL. Results showed a significant linear correlation between skin temperature and NN temperature at corresponding sites (r2 range, 0.4-0.84; p less than 0.005). Furthermore, both skin and NN temperatures correlated significantly with respective NCV and DL. Midline wrist skin temperature showed the best correlation to NCV and DL. Median motor and sensory NCV were altered 1.5 and 1.4m/sec/C degree and their DL 0.2 msec/C degree of wrist skin temperature change, respectively. Ulnar motor and sensory NCV were changed 2.1 and 1.6m/sec/C degree respectively, and 0.2 msec/C degree wrist temperature for motor and sensory DL. Average ambient skin temperature at the wrist (33 C) was used as a standard skin temperature in the temperature correction formula: NCV or DL(temp corrected) = CF(Tst degree - Tm degree) + obtained NCV or DL, where Tst = 33 C for wrist, Tm = the measured skin temperature, and CF = correction factor of tested nerve. Use of temperature correction formula for NCV and DL is suggested in patients with changed wrist skin temperature outside 29.6-36.4C temperature range. PMID:6615178

Halar, E M; DeLisa, J A; Soine, T L

1983-09-01

224

Thermal conductivity of suspended GaAs nanostructures: Theoretical study  

NASA Astrophysics Data System (ADS)

We present a theoretical investigation of the magnitude and temperature variation of the recently measured [Phys. Rev. B 66, 045302 (2002)] thermal conductivity of undoped and doped GaAs nanobeams of cross sections 100nm×250nm and 150nm×250nm , respectively. The calculations have been performed by employing Callaway’s theoretical model and Srivastava’s rigorous treatment of three-phonon interactions, based on an isotropic continuum phonon dispersion relation. It is found that an increased rate of diffuse surface scattering in undoped nanobeams explains the attenuation of the thermal conductivity below that of bulk GaAs well. The drop in thermal conductivity of doped nanobeams compared to that of the undoped beams arises from electron-phonon scattering and additional phonon scattering from a large number of point impurities due to the presence of dopant atoms. It is further shown that specular reflection of phonons from rough surfaces plays only a minor role in controlling the thermal conductivity of the nanobeams. The present calculations also allow for estimating the contributions of the longitudinal phonon branches and the three-phonon N -drift term towards the total conductivity.

Barman, Saswati; Srivastava, G. P.

2006-05-01

225

Binge eating disorder: its further validation in a multisite study.  

PubMed

Binge eating disorder (BED) is a new eating disorder that describes the eating disturbance of a large number of individuals who suffer from recurrent binge eating but who do not regularly engage in the compensatory behaviors to avoid weight gain seen in bulimia nervosa. This multisite study of BED involved 1,785 subjects drawn from 18 weight control programs, 942 subjects from five nonpatient community samples, and 75 patients with bulimia nervosa. Approximately 29% of subjects in weight control programs met the criteria for BED. In the nonpatient community samples BED was more common than purging bulimia nervosa. The validity of BED was supported by its strong association with (1) impairment in work and social functioning, (2) overconcern with body/shape and weight, (3) general psychopathology, (4) significant amount of time in adult life on diets, (5) a history of depression, alcohol/drug abuse, and treatment for emotional problems. PMID:8477283

Spitzer, R L; Yanovski, S; Wadden, T; Wing, R; Marcus, M D; Stunkard, A; Devlin, M; Mitchell, J; Hasin, D; Horne, R L

1993-03-01

226

New York State TrueAllele(®) Casework Validation Study.  

PubMed

DNA evidence can pose interpretation challenges, particularly with low-level or mixed samples. It would be desirable to make full use of the quantitative data, consider every genotype possibility, and objectively produce accurate and reproducible DNA match results. Probabilistic genotype computing is designed to achieve these goals. This validation study assessed TrueAllele(®) probabilistic computer interpretation on 368 evidence items in 41 test cases and compared the results with human review of the same data. Whenever there was a human result, the computer's genotype was concordant. Further, the computer produced a match statistic on 81 mixture items (for 87 inferred matching genotypes) in the test cases, while human review reported a statistic on 25 of these items (30.9%). Using match statistics to quantify information, probabilistic genotyping was shown to be sensitive, specific, and reproducible. These results demonstrate that objective probabilistic genotyping of biological evidence can reliably preserve DNA identification information. PMID:23865896

Perlin, Mark W; Belrose, Jamie L; Duceman, Barry W

2013-07-18

227

Secondary traumatic stress and vicarious trauma: a validational study.  

PubMed

Vicarious trauma (VT) and secondary traumatic stress (STS) or compassion fatigue both describe effects of working with traumatized persons on therapists. Despite conceptual similarities, their emphases differ: cognitive schemas vs. posttraumatic symptoms and burnout, respectively. The TSI Belief Scale (TSI-BSL) measures VT; the Compassion Fatigue Self-Test (CFST) for Psychotherapists measures STS. Neither has substantial psychometric evidence yet, nor has their association been studied. Results for 99 sexual assault and domestic violence counselors show concurrent validity between TSI-BSL and CFST, moderate convergence with burnout but useful discrimination, and strong convergence with general distress, but adequate independent shared variance. Counselors with interpersonal trauma histories scored higher on CFST, but not TSI-BSL or burnout, consistent with the CFST's emphasis on trauma symptomatology. PMID:12392231

Jenkins, Sharon Rae; Baird, Stephanie

2002-10-01

228

Transient hydraulic tomography in a sandbox with deterministic heterogeneity: Validation of hydraulic conductivity and specific storage tomograms  

Microsoft Academic Search

Hydraulic tomography is a method that images the hydraulic heterogeneity of the subsurface through the inversion of multiple pumping test data. Transient hydraulic tomography differentiates itself from steady-state tomography in that it not only estimates hydraulic conductivity but also provides an estimate of specific storage. Since it adopts transient pumping test data, it utilizes more data from each pumping test

X. Liu; W. A. Illman; A. J. Craig

2005-01-01

229

External Validity of Conduct and Oppositional Defiant Disorders Determined by the NIMH Diagnostic Interview Schedule for Children  

Microsoft Academic Search

We administered the Diagnostic Interview Schedule for Children (DISC) two times to a group of youth (222 boys, 147 girls) entering residential care, once at their time of entry and once 1 year later. We then compared their DISC outcomes on Conduct Disorder (CD) and Oppositional Defiant Disorder (ODD) against changes in independent direct observations of diagnostically relevant behavior obtained

Patrick C. Friman; Michael L. Handwerk; Gail L. Smith; Robert E. Larzelere; Christopher P. Lucas; David M. Shaffer

2000-01-01

230

A numerical study of coupled conduction - Mixed convection  

Microsoft Academic Search

The problem of coupled conduction - mixed convection for a circular cylinder with a heated core region in low Reynolds number flow is considered. The flow field and energy equations are solved under the conditions of equality in temperature and heat flux at the fluid - solid interface. The bouyancy forces are taken into account by using Boussinesq's approximation. Conditions

B. Sunden

1980-01-01

231

A benchmark study on the thermal conductivity of nanofluids  

Microsoft Academic Search

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or ``nanofluids,'' was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised

Jacopo Buongiorno; David C. Venerus; Naveen Prabhat; Thomas McKrell; Jessica Townsend; Rebecca J. Christianson; Yuriy V. Tolmachev; Pawel Keblinski; Lin-Wen Hu; Jorge L. Alvarado; In Cheol Bang; Sandra W. Bishnoi; Marco Bonetti; Frank Botz; Anselmo Cecere; Yun Chang; Gang Chen; Haisheng Chen; Sung Jae Chung; Minking K. Chyu; Sarit K. Das; Roberto di Paola; Yulong Ding; Frank Dubois; Grzegorz Dzido; Jacob Eapen; Werner Escher; Denis Funfschilling; Quentin Galand; Jinwei Gao; Patricia E. Gharagozloo; Kenneth E. Goodson; Jorge Gustavo Gutierrez; Haiping Hong; Mark Horton; Kyo Sik Hwang; Carlo S. Iorio; Seok Pil Jang; Andrzej B. Jarzebski; Yiran Jiang; Liwen Jin; Stephan Kabelac; Aravind Kamath; Mark A. Kedzierski; Lim Geok Kieng; Chongyoup Kim; Ji-Hyun Kim; Seokwon Kim; Seung Hyun Lee; Kai Choong Leong; Indranil Manna; Bruno Michel; Rui Ni; Hrishikesh E. Patel; John Philip; Dimos Poulikakos; Cecile Reynaud; Raffaele Savino; Pawan K. Singh; Pengxiang Song; Thirumalachari Sundararajan; Elena Timofeeva; Todd Tritcak; Aleksandr N. Turanov; Stefan van Vaerenbergh; Dongsheng Wen; Sanjeeva Witharana; Chun Yang; Wei-Hsun Yeh; Xiao-Zheng Zhao; Sheng-Qi Zhou

2009-01-01

232

Cyber Victim and Bullying Scale: A Study of Validity and Reliability  

ERIC Educational Resources Information Center

|The purpose of this study is to develop a reliable and valid scale, which determines cyber victimization and bullying behaviors of high school students. Research group consisted of 404 students (250 male, 154 male) in Sakarya, in 2009-2010 academic years. In the study sample, mean age is 16.68. Content validity and face validity of the scale was…

Cetin, Bayram; Yaman, Erkan; Peker, Adem

2011-01-01

233

Cyber victim and bullying scale: A study of validity and reliability  

Microsoft Academic Search

The purpose of this study is to develop a reliable and valid scale, which determines cyber victimization and bullying behaviors of high school students. Research group consisted of 404 students (250 male, 154 male) in Sakarya, in 2009–2010 academic years. In the study sample, mean age is 16.68. Content validity and face validity of the scale was provided via field

Bayram Çetin; Erkan Yaman; Adem Peker

2011-01-01

234

Nuclear Spin Lattice Relaxation and Conductivity Studies of the Non-Arrhenius Conductivity Behavior in Lithium Fast Ion Conducting Sulfide Glasses  

SciTech Connect

As time progresses, the world is using up more of the planet's natural resources. Without technological advances, the day will eventually arrive when these natural resources will no longer be sufficient to supply all of the energy needs. As a result, society is seeing a push for the development of alternative fuel sources such as wind power, solar power, fuel cells, and etc. These pursuits are even occurring in the state of Iowa with increasing social pressure to incorporate larger percentages of ethanol in gasoline. Consumers are increasingly demanding that energy sources be more powerful, more durable, and, ultimately, more cost efficient. Fast Ionic Conducting (FIC) glasses are a material that offers great potential for the development of new batteries and/or fuel cells to help inspire the energy density of battery power supplies. This dissertation probes the mechanisms by which ions conduct in these glasses. A variety of different experimental techniques give a better understanding of the interesting materials science taking place within these systems. This dissertation discusses Nuclear Magnetic Resonance (NMR) techniques performed on FIC glasses over the past few years. These NMR results have been complimented with other measurement techniques, primarily impedance spectroscopy, to develop models that describe the mechanisms by which ionic conduction takes place and the dependence of the ion dynamics on the local structure of the glass. The aim of these measurements was to probe the cause of a non-Arrhenius behavior of the conductivity which has been seen at high temperatures in the silver thio-borosilicate glasses. One aspect that will be addressed is if this behavior is unique to silver containing fast ion conducting glasses. more specifically, this study will determine if a non-Arrhenius correlation time, {tau}, can be observed in the Nuclear Spin Lattice Relaxation (NSLR) measurements. If so, then can this behavior be modeled with a new single distribution of activation energies (DAE) to calculate the corresponding conductivity and relaxation rates as a function of temperature and frequency?

Benjamin Michael Meyer

2003-05-31

235

Evaluating hormonal mechanisms of vitamin D receptor agonist therapy in diabetic kidney disease: the VALIDATE-D study  

PubMed Central

Background Insufficient vitamin D status and increased renin-angiotensin system (RAS) activity have been associated with renal-vascular disease and nephropathy in diabetes. Accumulating evidence indicates that vitamin D receptor (VDR) activation lowers unfavorable RAS activity; however, more human intervention studies evaluating whether this mechanism could influence diabetic kidney disease are needed. We previously reported that both vitamin D levels and genetic variation at the VDR predict human RAS activity, and that vitamin D therapy can lower RAS activity in non-diabetics. The VALIDATE-D study is a randomized, placebo-controlled, intervention study designed to extend these findings by evaluating whether direct VDR activation in diabetes lowers circulating and local renal-vascular tissue RAS activity (Aims 1 and 2) in a manner similar to the action of ACE inhibitors (Aim 3). Methods/Design Forty subjects with type 2 diabetes, microalbuminuria, and without chronic kidney disease will be recruited to undergo detailed assessment of the RAS before and after randomization to calcitriol 0.75 mcg/day or placebo. Primary analyses will evaluate whether calcitriol therapy reduces circulating and renal-vascular tissue-RAS activity in comparison to placebo. All subjects will thereafter be treated with lisinopril and followed for 3.5 months to evaluate whether combination therapy (calcitriol?+?lisinopril vs. placebo?+?lisinopril) additively or synergistically improves renal-vascular function, and lowers proteinuria. Discussion The VALIDATE-D study is the first human intervention study to evaluate whether direct VDR activation can lower the human RAS in diabetes, compared to the effect of an ACE inhibitor, and whether this mechanism can translate to clinically relevant endpoints for diabetic kidney disease. The outcomes of VALIDATE-D will have major implications for the recommendation of vitamin D supplementation for the primary prevention of kidney complications in diabetes. Trial registration ClinicalTrials.gov, NCT01635062

2013-01-01

236

A theoretical study of the structure and conductivity of polycytosineacetylene  

NASA Astrophysics Data System (ADS)

Inspired by the helical structure as well as the conductivity of DNA and substituted polyphenylacetylenes, a new kind of substituted polyacetylene is introduced. More specifically, polycytosineacetylene ((RC dbnd CH) n, R = cytosine) with a trans-polyacetylene backbone is investigated theoretically. The neutral and cationic geometries are optimized as single helical chains with n = 20. It is found that when an electron is removed the polymer stretches from 19.80 Å to 28.41 Å. The polyacetylene backbone in the optimized cationic polymer exhibits the formation of a soliton. It is predicted that a doped polycytosineacetylene would have good conductivity, and would also behave as a nanomechanical spring and as a piezoelectric material.

Wu, Jian; Walker, Victoria E. J.; Boyd, Russell J.

2011-04-01

237

Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study  

PubMed Central

Background: In the assessment of severity in community acquired pneumonia (CAP), the modified British Thoracic Society (mBTS) rule identifies patients with severe pneumonia but not patients who might be suitable for home management. A multicentre study was conducted to derive and validate a practical severity assessment model for stratifying adults hospitalised with CAP into different management groups. Methods: Data from three prospective studies of CAP conducted in the UK, New Zealand, and the Netherlands were combined. A derivation cohort comprising 80% of the data was used to develop the model. Prognostic variables were identified using multiple logistic regression with 30 day mortality as the outcome measure. The final model was tested against the validation cohort. Results: 1068 patients were studied (mean age 64 years, 51.5% male, 30 day mortality 9%). Age ?65 years (OR 3.5, 95% CI 1.6 to 8.0) and albumin <30 g/dl (OR 4.7, 95% CI 2.5 to 8.7) were independently associated with mortality over and above the mBTS rule (OR 5.2, 95% CI 2.7 to 10). A six point score, one point for each of Confusion, Urea >7 mmol/l, Respiratory rate ?30/min, low systolic(<90 mm Hg) or diastolic (?60 mm Hg) Blood pressure), age ?65 years (CURB-65 score) based on information available at initial hospital assessment, enabled patients to be stratified according to increasing risk of mortality: score 0, 0.7%; score 1, 3.2%; score 2, 3%; score 3, 17%; score 4, 41.5% and score 5, 57%. The validation cohort confirmed a similar pattern. Conclusions: A simple six point score based on confusion, urea, respiratory rate, blood pressure, and age can be used to stratify patients with CAP into different management groups.

Lim, W; van der Eerden, M M; Laing, R; Boersma, W; Karalus, N; Town, G; Lewis, S; Macfarlane, J

2003-01-01

238

Ionic Conductivity And Structural Relaxation Studies on Lithium Niobophosphate Glass  

SciTech Connect

Niobium pentoxide (Nb{sub 2}O{sub 5}) increases the chemical and thermal stability of otherwise hygroscopic alkali phosphate glasses and also enhances the conduction characteristics. Ion dynamics and structural relaxation have been investigated for mol%50Li{sub 2}0-45P{sub 2}0{sub 5}-5Nb{sub 2}O{sub 5}. The non-linearity parameter 'x' in the Tool-Narayanaswamy model is evaluated using the dependence of fictive and glass transition temperatures on the cooling and heating rates.

Dabas, Prashant; Hariharan, K. [Department of physics, Indian Institute of Technology Madras, Chennai-600036 (India)

2011-07-15

239

Field Validation Study of NO2 Personal Passive Samplers in a “Diesel” Haulage Underground Mine  

Microsoft Academic Search

Three passive samplers are now commercially available for NO2. This field validation, conducted in an underground mine, attempted to address both the precision and accuracy of the three now commercially available. The probable sources of NO2 were identified as diesel engines and blasting operations. Comparative sampling was conducted with the passive samplers versus the standard “baseline” impingement method. The three

KENNETH E. DOUGLAS; HARRY J. BEAULIEU

1983-01-01

240

40 CFR 761.386 - Required experimental conditions for the validation study and subsequent use during decontamination.  

Code of Federal Regulations, 2013 CFR

...experimental conditions for the validation study and subsequent use during decontamination...COMMERCE, AND USE PROHIBITIONS Comparison Study for Validating a New Performance-Based...experimental conditions for the validation study and subsequent use during...

2013-07-01

241

Scanning ion conductance microscopy for studying biological samples.  

PubMed

Scanning ion conductance microscopy (SICM) is a scanning probe technique that utilizes the increase in access resistance that occurs if an electrolyte filled glass micro-pipette is approached towards a poorly conducting surface. Since an increase in resistance can be monitored before the physical contact between scanning probe tip and sample, this technique is particularly useful to investigate the topography of delicate samples such as living cells. SICM has shown its potential in various applications such as high resolution and long-time imaging of living cells or the determination of local changes in cellular volume. Furthermore, SICM has been combined with various techniques such as fluorescence microscopy or patch clamping to reveal localized information about proteins or protein functions. This review details the various advantages and pitfalls of SICM and provides an overview of the recent developments and applications of SICM in biological imaging. Furthermore, we show that in principle, a combination of SICM and ion selective micro-electrodes enables one to monitor the local ion activity surrounding a living cell. PMID:23202197

Happel, Patrick; Thatenhorst, Denis; Dietzel, Irmgard D

2012-11-06

242

A Validity Study of the Kinetic School Drawing Technique.  

ERIC Educational Resources Information Center

|Examined the relationship between Kinetic School Drawing responses and academic achievement in 100 normal fifth-grade students. Significant correlations were found for a number of measures, generally supporting the validity of the technique. (JAC)|

Prout, H. Thompson; Celmer, David S.

1984-01-01

243

The Predictive Validity of Preadmission Measures in Graduate Management Education: Three Years of the GMAC Validity Study Service.  

ERIC Educational Resources Information Center

The Graduate Management Admission Council (GMAC) Validity Study Service was created to enable graduate schools of management to investigate the adequacy of the devices and procedures they use for selection purposes and to facilitate the accumulation and summary of data from many individual graduate management schools. Participating schools are…

Hecht, Lawrence W.; Powers, Donald E.

244

The Predictive Validity of Preadmission Measures in Graduate Management Education: Three Years of the GMAC Validity Study Service.  

ERIC Educational Resources Information Center

|The Graduate Management Admission Council (GMAC) Validity Study Service was created to enable graduate schools of management to investigate the adequacy of the devices and procedures they use for selection purposes and to facilitate the accumulation and summary of data from many individual graduate management schools. Participating schools are…

Hecht, Lawrence W.; Powers, Donald E.

245

MINET validation study using steam generator transient data  

SciTech Connect

Three steam generator transient test cases, that were simulated using the MINET computer code, are described, with computed results compared against experimental data. The MINET calculations closely agreed with the experiment for both the once-through and the U-tube steam generator test cases. The effort is part of an ongoing effort to validate the MINET computer code for thermal-hydraulic plant systems transient analysis, and strongly supports the validity of the MINET models.

Van Tuyle, G.J.

1984-05-01

246

Discriminant construct validity of ImPACT™: a companion study.  

PubMed

In a previous analysis of ImPACT scores relative to traditional neuropsychological tests (NP) and experimental tasks (Maerlender et al., 2010 ) we demonstrated convergent construct validity for the primary ImPACT test-score composites. A complete analysis of discriminant validity was not undertaken at that time. Here, test scores from the 54 collegiate football and hockey players were re-analyzed to specifically address the discriminant validity of the ImPACT™ composite scores using a multiply operationalized correlation matrix of multi-trait multi-method data. In the method used here, discriminant validity is determined by obtaining non-significant correlations between a target score when correlated with the average of the other trait measurements (multiply-operationalized multi-trait-mono-method analysis). Results showed that the ImPACT™ Verbal Memory (p?=?.044), Visual Memory (p?=?.006), and Visual Motor Speed (p?=?.000) scores were highly correlated with composites of the other scores, while the Reaction Time composite demonstrated adequate discriminant validity (p?=?.145). In comparison all of the NP composites showed good discrimination (all p-values >.05, except for Reaction Time p?=?.05). Thus the apparent lack of discriminability between three of four composite scores in this sample raises questions about using ImPACT™ composite scores to support specific construct-oriented interpretations. Taken together, the discriminant and convergent construct validity properties of ImPACT™ indicate construct sensitivity, but limited construct specificity. PMID:23317033

Maerlender, A; Flashman, L; Kessler, A; Kumbhani, S; Greenwald, R; Tosteson, T; McAllister, T

2013-01-14

247

The Hong Kong Early Child Development Scale: A Validation Study.  

PubMed

This paper reports on the development and validation of the Hong Kong Early Child Development Scale (HKECDS), a holistic measure of child development designed specifically for preschool children in Hong Kong. Scale development was an iterative process and the first version of the scale contained 190 items whereas the final version includes only 95. Children ranging in age from three to six years were administered trial versions of the HKECDS in Studies 1 (n?=?60) and 2 (n?=?240). Item analyses indicated that it is a developmental scale and that it has an appropriate level of difficulty for preschool children. It also discriminates between three- to six-year-olds from different social backgrounds in Hong Kong. The final version of the HKECDS includes items from the following eight subscales: Personal, Social and Self-Care (7 items), Language Development (13 items), Pre-academic Learning (27 items), Cognitive Development (10 items), Gross Motor (12 items), Fine Motor (9 items), Physical Fitness, Health and Safety (7 items), and Self and Society (10 items). The HKECDS is the first early child development scale which considers both the holistic development of preschool children and incorporates current expectations of early child development in Hong Kong. In this era of evidence-based decision making, it can be used to evaluate both the efficacy of targeted interventions and broader child-related public policies on early child development in Hong Kong. PMID:23420045

Rao, Nirmala; Sun, Jin; Ng, Sharon Sui Ngan; Ma, Kitty; Becher, Yvonne; Lee, Diana; Lau, Carrie; Zhang, Li; Chow, Chun Bong; Ip, Patrick

2012-10-01

248

In Vivo Characterization of Pancreatic and Lymph Node Tissue using Endoscopic Ultrasound Spectrum Analysis: Validation Study  

PubMed Central

Background Quantitative spectral analysis of the radio-frequency (RF) signals that underlie grayscale EUS images can be used to provide additional, objective information about tissue state. Objective Our purpose was to validate RF spectral analysis as a method to distinguish between (1) benign and malignant lymph nodes and (2) normal pancreas (NP), chronic pancreatitis (CP) and pancreatic cancer (PC). Design & Setting A prospective validation study of eligible patients was conducted to compare with pilot study RF data. Patients Forty-three patients underwent EUS of the esophagus, stomach, pancreas, and surrounding intra-abdominal and mediastinal lymph nodes (19 from previous pilot study and 24 additional patients). Main Outcome Measurements Midband fit, slope, intercept, and correlation coefficient from a linear regression of the calibrated RF power spectra were determined. Results Discriminant analysis of mean pilot-study parameters was then performed to classify validation-study parameters. For benign vs. malignant lymph nodes, midband-fit and intercept (both with t-test p < 0.058) provided classification with 67% accuracy and area under ROC curve (AUC) of 0.86. For diseased vs. NP, midband-fit and correlation coefficient (both with ANOVA p < 0.001) provided 93% accuracy and AUC of 0.98. For PC vs. CP, the same parameters provided 77% accuracy and AUC of 0.89. Results improved further when classification was performed with all data. Limitations Moderate sample size and spatial averaging inherent to the technique. Conclusions This study confirms that mean spectral parameters provide a non-invasive method to quantitatively discriminate benign and malignant lymph nodes as well as normal and diseased pancreas.

Kumon, Ronald E.; Pollack, Michael J.; Faulx, Ashley L.; Olowe, Kayode; Farooq, Farees T.; Chen, Victor K.; Zhou, Yun; Wong, Richard C. K.; Isenberg, Gerard A.; Sivak, Michael V.; Chak, Amitabh; Deng, Cheri X.

2009-01-01

249

Interface proximity effects on ionic conductivity in nanoscale oxide-ion conducting yttria stabilized zirconia: An atomistic simulation study  

NASA Astrophysics Data System (ADS)

We present an atomistic simulation study on the size dependence of dopant distribution and the influence of nanoscale film thickness on carrier transport properties of the model oxide-ion conductor yttria stabilized zirconia (YSZ). Simulated amorphization and recrystallization approach was utilized to generate YSZ films with varying thicknesses (3-9 nm) on insulating MgO substrates. The atomic trajectories generated in the molecular dynamics simulations are used to study the structural evolution of the YSZ thin films and correlate the resulting microstructure with ionic transport properties at the nanoscale. The interfacial conductivity increases by 2 orders of magnitude as the YSZ film size decreases from 9 to 3 nm owing to a decrease in activation energy barrier from 0.54 to 0.35 eV in the 1200-2000 K temperature range. Analysis of dopant distribution indicates surface enrichment, the extent of which depends on the film thickness. The mechanisms of oxygen conductivity for the various film thicknesses at the nanoscale are discussed in detail and comparisons with experimental and other modeling studies are presented where possible. The study offers insights into mesoscopic ion conduction mechanisms in low-dimensional solid oxide electrolytes.

Sankaranarayanan, Subramanian K. R. S.; Ramanathan, Shriram

2011-02-01

250

Validation Studies of the The MONICA Optional Study of Physical Activity (MOSPA-Q)  

Cancer.gov

Validation Studies of the The MONICA Optional Study of Physical Activity (MOSPA-Q) Roeykens et al. 1998 See reference #45 Methods Relation between MOSPA-Q items by time scores (i.e. WORK) and EE spent in activity category (i.e. KWORK) and biometrical

251

Validation Studies of the The MONICA Optional Study of Physical Activity (MOSPA-Q)  

Cancer.gov

Validation Studies of the The MONICA Optional Study of Physical Activity (MOSPA-Q) Iqbal et al. 2006 See reference #86 Methods MOSPA-Q long term questionnaire (LT) and short term questionnaire measuring five days of activity (ST) compared to Caltrac

252

Towards environmental construct validity in animal models of CNS disorders: optimizing translation of preclinical studies.  

PubMed

There is an enormous demand for new therapeutic interventions for a range of major disorders. The majority of clinical trials in recent years have been unsuccessful despite highly promising preclinical data. Therefore, an urgent issue confronting both the academic and commercial medical research sectors is how to optimize translation of preclinical studies. The vast majority of preclinical studies are currently performed using laboratory mice and rats. We will discuss the various opportunities for optimization of animal models of CNS disorders. One limitation of current approaches is that most studies are conducted on sedentary, unstimulated animals with unlimited access to food in the home cage, thus leading to metabolic and physiological compromise. Environmental enrichment, which enhances sensory stimulation, cognitive activity and physical exercise, has been demonstrated to induce dramatic effects on brain and behavior in both wild-type and genetically modified rodent models, relative to standard-housed littermate controls. Environmental enrichment also exerts beneficial effects outside the CNS, such as a reduction in excess body fat. We propose that therapeutic interventions which are found to show promise in standard-housed preclinical models should be subsequently tested under conditions of greater environmental enrichment to identify therapeutics which continue to show efficacy in housing contexts of superior 'environmental construct validity'. Other possible approaches to optimize the quality, validity and reporting of preclinical studies in animal models are also discussed. PMID:23574171

Burrows, Emma L; Hannan, Anthony J

2013-08-01

253

Systematic validation of disease models for pharmacoeconomic evaluations. Swiss HIV Cohort Study.  

PubMed

Pharmacoeconomic evaluations are often based on computer models which simulate the course of disease with and without medical interventions. The purpose of this study is to propose and illustrate a rigorous approach for validating such disease models. For illustrative purposes, we applied this approach to a computer-based model we developed to mimic the history of HIV-infected subjects at the greatest risk for Mycobacterium avium complex (MAC) infection in Switzerland. The drugs included as a prophylactic intervention against MAC infection were azithromycin and clarithromycin. We used a homogenous Markov chain to describe the progression of an HIV-infected patient through six MAC-free states, one MAC state, and death. Probability estimates were extracted from the Swiss HIV Cohort Study database (1993-95) and randomized controlled trials. The model was validated testing for (1) technical validity (2) predictive validity (3) face validity and (4) modelling process validity. Sensitivity analysis and independent model implementation in DATA (PPS) and self-written Fortran 90 code (BAC) assured technical validity. Agreement between modelled and observed MAC incidence confirmed predictive validity. Modelled MAC prophylaxis at different starting conditions affirmed face validity. Published articles by other authors supported modelling process validity. The proposed validation procedure is a useful approach to improve the validity of the model. PMID:10461580

Sendi, P P; Craig, B A; Pfluger, D; Gafni, A; Bucher, H C

1999-08-01

254

Alaska North Slope Tundra Travel Model and Validation Study  

SciTech Connect

The Alaska Department of Natural Resources (DNR), Division of Mining, Land, and Water manages cross-country travel, typically associated with hydrocarbon exploration and development, on Alaska's arctic North Slope. This project is intended to provide natural resource managers with objective, quantitative data to assist decision making regarding opening of the tundra to cross-country travel. DNR designed standardized, controlled field trials, with baseline data, to investigate the relationships present between winter exploration vehicle treatments and the independent variables of ground hardness, snow depth, and snow slab thickness, as they relate to the dependent variables of active layer depth, soil moisture, and photosynthetically active radiation (a proxy for plant disturbance). Changes in the dependent variables were used as indicators of tundra disturbance. Two main tundra community types were studied: Coastal Plain (wet graminoid/moist sedge shrub) and Foothills (tussock). DNR constructed four models to address physical soil properties: two models for each main community type, one predicting change in depth of active layer and a second predicting change in soil moisture. DNR also investigated the limited potential management utility in using soil temperature, the amount of photosynthetically active radiation (PAR) absorbed by plants, and changes in microphotography as tools for the identification of disturbance in the field. DNR operated under the assumption that changes in the abiotic factors of active layer depth and soil moisture drive alteration in tundra vegetation structure and composition. Statistically significant differences in depth of active layer, soil moisture at a 15 cm depth, soil temperature at a 15 cm depth, and the absorption of photosynthetically active radiation were found among treatment cells and among treatment types. The models were unable to thoroughly investigate the interacting role between snow depth and disturbance due to a lack of variability in snow depth cover throughout the period of field experimentation. The amount of change in disturbance indicators was greater in the tundra communities of the Foothills than in those of the Coastal Plain. However the overall level of change in both community types was less than expected. In Coastal Plain communities, ground hardness and snow slab thickness were found to play an important role in change in active layer depth and soil moisture as a result of treatment. In the Foothills communities, snow cover had the most influence on active layer depth and soil moisture as a result of treatment. Once certain minimum thresholds for ground hardness, snow slab thickness, and snow depth were attained, it appeared that little or no additive effect was realized regarding increased resistance to disturbance in the tundra communities studied. DNR used the results of this modeling project to set a standard for maximum permissible disturbance of cross-country tundra travel, with the threshold set below the widely accepted standard of Low Disturbance levels (as determined by the U.S. Fish and Wildlife Service). DNR followed the modeling project with a validation study, which seemed to support the field trial conclusions and indicated that the standard set for maximum permissible disturbance exhibits a conservative bias in favor of environmental protection. Finally DNR established a quick and efficient tool for visual estimations of disturbance to determine when investment in field measurements is warranted. This Visual Assessment System (VAS) seemed to support the plot disturbance measurements taking during the modeling and validation phases of this project.

Harry R. Bader; Jacynthe Guimond

2006-03-01

255

40 CFR 761.386 - Required experimental conditions for the validation study and subsequent use during decontamination.  

Code of Federal Regulations, 2010 CFR

...validation study and subsequent use during decontamination. 761.386 Section 761.386...Validating a New Performance-Based Decontamination Solvent Under ç 761.79(d...validation study and subsequent use during decontamination. The following experimental...

2010-07-01

256

40 CFR 761.386 - Required experimental conditions for the validation study and subsequent use during decontamination.  

Code of Federal Regulations, 2010 CFR

...validation study and subsequent use during decontamination. 761.386 Section 761.386...Validating a New Performance-Based Decontamination Solvent Under ç 761.79(d...validation study and subsequent use during decontamination. The following experimental...

2009-07-01

257

Propeller aircraft interior noise model utilization study and validation  

NASA Astrophysics Data System (ADS)

Utilization and validation of a computer program designed for aircraft interior noise prediction is considered. The program, entitled PAIN (an acronym for Propeller Aircraft Interior Noise), permits (in theory) predictions of sound levels inside propeller driven aircraft arising from sidewall transmission. The objective of the work reported was to determine the practicality of making predictions for various airplanes and the extent of the program's capabilities. The ultimate purpose was to discern the quality of predictions for tonal levels inside an aircraft occurring at the propeller blade passage frequency and its harmonics. The effort involved three tasks: (1) program validation through comparisons of predictions with scale-model test results; (2) development of utilization schemes for large (full scale) fuselages; and (3) validation through comparisons of predictions with measurements taken in flight tests on a turboprop aircraft. Findings should enable future users of the program to efficiently undertake and correctly interpret predictions.

Pope, L. D.

1984-09-01

258

Physics validation studies for muon collider detector background simulations  

SciTech Connect

Within the broad discipline of physics, the study of the fundamental forces of nature and the most basic constituents of the universe belongs to the field of particle physics. While frequently referred to as 'high-energy physics,' or by the acronym 'HEP,' particle physics is not driven just by the quest for ever-greater energies in particle accelerators. Rather, particle physics is seen as having three distinct areas of focus: the cosmic, intensity, and energy frontiers. These three frontiers all provide different, but complementary, views of the basic building blocks of the universe. Currently, the energy frontier is the realm of hadron colliders like the Tevatron at Fermi National Accelerator Laboratory (Fermilab) or the Large Hadron Collider (LHC) at CERN. While the LHC is expected to be adequate for explorations up to 14 TeV for the next decade, the long development lead time for modern colliders necessitates research and development efforts in the present for the next generation of colliders. This paper focuses on one such next-generation machine: a muon collider. Specifically, this paper focuses on Monte Carlo simulations of beam-induced backgrounds vis-a-vis detector region contamination. Initial validation studies of a few muon collider physics background processes using G4beamline have been undertaken and results presented. While these investigations have revealed a number of hurdles to getting G4beamline up to the level of more established simulation suites, such as MARS, the close communication between us, as users, and the G4beamline developer, Tom Roberts, has allowed for rapid implementation of user-desired features. The main example of user-desired feature implementation, as it applies to this project, is Bethe-Heitler muon production. Regarding the neutron interaction issues, we continue to study the specifics of how GEANT4 implements nuclear interactions. The GEANT4 collaboration has been contacted regarding the minor discrepancies in the neutron interaction cross sections for boron. While corrections to the data files themselves are simple to implement and distribute, it is quite possible, however, that coding changes may be required in G4beamline or even in GEANT4 to fully correct nuclear interactions. Regardless, these studies are ongoing and future results will be reflected in updated releases of G4beamline.

Morris, Aaron Owen; /Northern Illinois U.

2011-07-01

259

Application of artificial mussels (AMs) under South African marine conditions: a validation study.  

PubMed

Over the last three decades there has been a significant decline in the number of marine pollution monitoring-related studies in South Africa. Thus, the current study was conducted to assess the current state of metal contamination within the South African marine environment through the validation of the artificial mussel (AM). Indigenous reference mussels (Perna perna) were deployed alongside the passive device within the South African marine environment for a 6 week exposure period. Analysis of metal uptake (Cd, Cr, Cu, Pb and Zn) was determined by filtration and elution of the AM chelex resins, microwave digestion of the transplanted mussels, and determination of their metal concentrations by ICP-MS and ICP-OES analysis. Uptake patterns between the AM and transplanted mussels showed significant temporal and spatial correlation for the majority of the elements analysed. While the AM provided relevant and complementary information on the dissolved metal concentrations, limitations were also observed. PMID:21596395

Degger, N; Wepener, V; Richardson, B J; Wu, R S S

2011-05-18

260

The validity of a portable clinical force plate in assessment of static postural control: concurrent validity study  

PubMed Central

Background The broad use of force plates in clinical settings for postural control assessment suggests the need for instruments that are easy to use, affordable and readily available. In addition, these instruments of measurement should be reliable and valid as adequate reliability and validity are prerequisites to making correct inferences. The aim of this study was to examine the concurrent validity of postural control measures obtained with a clinical force plate. Methods Thirty-one healthy adults were recruited. Participants completed 1 set of 5 trials on each force plate. Postural control measures (centre of pressure [COP] average velocity and sway area) were collected and compared using the Midot Posture Scale Analyzer (clinical force plate) and the Accugait force plate (criterion measure). Intra class correlation coefficient (ICC), standard error of measurement , and paired t-tests were calculated and Bland-Altman plots were constructed to compare the force plates and assess consistency of measurement and agreement between them. Results The ICC values (ICC?=?0.14-0.60) between the two force plates were lower than the acceptable value for both COP average velocity and sway area. There was significant difference (p?>?0.05) in COP average velocity and sway area between the force plates. Examination of the plots revealed that there is less difference between the force plates in lower magnitudes of COP for average velocity and sway area however, the greater the average velocity and sway area, the greater the difference between the measures obtained from the two force plates. Conclusion Findings of this study showed poor concurrent validity of the clinical force plate. This clinical force plate cannot be a replacement for known reliable and valid force plates and consequently measures obtained from this force plate should be treated with caution especially in a clinical population.

2012-01-01

261

40 CFR 160.130 - Conduct of a study.  

Code of Federal Regulations, 2011 CFR

...be identified by test system, study, nature, and date of collection. This information...generated by automated data collection systems, shall be recorded...change. In automated data collection systems, the individual...

2011-07-01

262

Covariance and Regression Slope Models for Studying Validity Generalization  

Microsoft Academic Search

Two new models, the covariance and regression slope models, are proposed for assessing validity gen eralization. The new models are less restrictive in that they require only one hypothetical distribution (distri bution of range restriction for the covariance model and distribution of predictor reliability for the regres sion slope model) for their implementation, in contrast to the correlation model which

Nambury S. Raju; Rodney Fralicx; Stephen D. Steinhaus

1986-01-01

263

Study on the Validity of Effective Hamiltonian in Multiphoton Lasers.  

National Technical Information Service (NTIS)

Two-photon processes, which form the basis for two-photon lasers and masers, are usually treated using an effective Hamiltonian approach. In this dissertation the author has considered the question of validity of effective Hamiltonian in the interaction o...

A. H. Toor

1990-01-01

264

Anthropometric Sizing Study for the Canadian Forces: Matched Database Validation.  

National Technical Information Service (NTIS)

A validation sample of 535 male Canadian Forces (CF) was measured. Unfortunately, the measuring sites chosen by the CF were atypical and led to a non-random sample. Prior to discovering this bias, the data were utilized to explore several alternative matc...

C. C. Gordon E. A. Carson S. M. Donelson S. P. Paquette

1996-01-01

265

29 CFR 1607.7 - Use of other validity studies.  

Code of Federal Regulations, 2013 CFR

...clearly demonstrates that the selection procedure is valid; (2...and on the job for which the selection procedure is to be used; and...test fairness for each race, sex, and ethnic group which...acted upon. Users obtaining selection procedures from...

2013-07-01

266

Factors in Validating Affective Scales: An Applied Study  

Microsoft Academic Search

In spite of claims to the contrary, affective factors related to teaching and learning can be measured. Recent development of affective scales in reading attest to this, yet caution must be observed that as new-scales are developed, they are adequately validated so that the research emanating from their use can be regarded with a high degree of credibility. In that

Joseph Vaughan; Darrell Sabers

1977-01-01

267

A Validity Study of the Salter Environmental Type Assessment.  

ERIC Educational Resources Information Center

|Correlational analyses of data from 202 students on the Work Environment Scale and Salter Environmental Type Assessment (SETA) supported concurrent validity. Factor analysis identified three factors accounting for 70% of variance: positive work settings, structure, and work pressure/task orientation. SETA appears useful as a commensurate Myers…

Salter, Daniel W.

2002-01-01

268

Behavioral and Emotional Rating Scale: Two Studies of Convergent Validity  

ERIC Educational Resources Information Center

|As the field of mental health services shifts its focus to early intervention, the need to develop valid and reliable measures of young children's behavioral functioning is clear. Traditional assessment instruments have focused on deficits, problems, and pathologies to the exclusion of strengths and competencies. However, assessing child…

Trout, Alexandra L.; Ryan, Joseph B.; La Vigne, Steven P.; Epstein, Michael H.

2003-01-01

269

The Client Satisfaction Inventory: Results of an Initial Validation Study  

Microsoft Academic Search

Objective: To obtain initial results with regard to the reliability and validity of the Client Satis- faction Inventory (CSI), a 25-item scale for measuring general satisfaction with services among clients of human service agencies. Method: The CSI was administered to 329 clients of 11 agen- cies in six states. Also administered were three other standardized measures and a brief descrip-

Steven L. McMurtry

270

Training Objectives, Transfer, Validation and Evaluation: A Sri Lankan Study  

ERIC Educational Resources Information Center

|Using a stratified random sample, this paper examines the training practices of setting objectives, transfer, validation and evaluation in Sri Lanka. The paper further sets out to compare those practices across local, foreign and joint-venture companies based on the assumption that there may be significant differences across companies of…

Wickramasinghe, Vathsala M.

2006-01-01

271

Prenatal Child Abuse Risk Assessment: A Preliminary Validation Study.  

ERIC Educational Resources Information Center

|Tested the validity of the Brigid Collins Risk Screener (BCRS) to assess child abuse risk in a sample of 49 expectant mothers. Found that at 3 months postpartum, high-risk mothers scored significantly lower on the quality of infants' physical, social, and emotional environments than moderate or low-risk mothers. Concluded that the BCRS appears to…

Weberling, Lara Cady; Forgays, Deborah Kirby; Crain-Thoreson, Catherine; Hyman, Ira

2003-01-01

272

Minet validation study using EBR-II transient data  

SciTech Connect

The MINET code, developed to simulate large and complex thermal-hydraulic systems, such as balance of plant, was used to simulate an EBR-II test transient. MINET calculations agreed well with measured parameters, confirming the validity of the basic MINET methodology and key component models.

Van Tuyle, G.J.

1984-01-01

273

Ultrasound Assessment of Transverse Carpal Ligament Thickness: A Validity and Reliability Study  

PubMed Central

The transverse carpal ligament (TCL) forms the palmar boundary of the carpal tunnel and plays an important role in carpal tunnel mechanics. TCL hypertrophy has been observed for individuals with carpal tunnel syndrome (CTS) and postulated as a potential etiological factor. Ultrasound is particularly advantageous for TCL imaging because of its capability of detecting the interfaces between the TCL and other tissues. The purposes of this study were to develop an ultrasound based method to measure the TCL thickness and to test the validity and reliability of this method. Three operators conducted two sessions of ultrasound examination on 8 cadaveric specimens and 8 healthy volunteers. A custom script was used to calculate TCL thickness along the TCL length from the ultrasound images. The ultrasound based TCL thickness of the cadaveric specimens was compared to the dissection based TCL thickness for validation. The results showed Pearson’s correlation coefficients of 0.867–0.928, intraclass correlation coefficient (ICC) values of 0.726–0.865, a standard error of measurement of 0.02–0.07 mm, and a minimal detectable difference of 0.05–0.15 mm. The high correlation coefficients and small errors indicate that the ultrasound based method is valid for measuring TCL thickness. Furthermore, ultrasound measurements showed excellent intra-operator and inter-operator reliability with ICC values as 0.826–0.933 and 0.840–0.882, respectively. The ultrasound based TCL thickness was in the range of 0.93–2.34 (1.54 ± 0.33) mm and agreed well with previous studies. The ultrasound method developed in this study is a valuable tool to examine morphological properties of healthy and pathological TCLs.

Shen, Zhilei Liu; Li, Zong-Ming

2012-01-01

274

Validation of reference genes for RT-qPCR studies of gene expression in banana fruit under different experimental conditions  

Microsoft Academic Search

Reverse transcription quantitative real-time PCR (RT-qPCR) is a sensitive technique for quantifying gene expression, but its\\u000a success depends on the stability of the reference gene(s) used for data normalization. Only a few studies on validation of\\u000a reference genes have been conducted in fruit trees and none in banana yet. In the present work, 20 candidate reference genes\\u000a were selected, and

Lei ChenHai-ying; Hai-ying Zhong; Jian-fei Kuang; Jian-guo Li; Wang-jin Lu; Jian-ye Chen

275

Predicting NCLEX-RN success with the HESI Exit Exam: eighth validity study.  

PubMed

Increasingly, Elsevier's HESI Exit Exam (E(2)) is being used to assess students' readiness for the National Council Licensure Examination for Registered Nurses (NCLEX-RN). Seven previously conducted validity studies indicate that the E(2) is 96.36%-99.16% accurate in predicting NCLEX-RN success. Findings of this eighth validity study, which also investigated the predictive accuracy of repeat testing with parallel versions of the E(2), indicated that the E(2) is highly accurate (94.93%-98.32%) in predicting NCLEX-RN success for the initial testing and 2 retests. Of the 66 participating nursing programs, deans and directors from 43 (65.15%) of the programs reported implementing a policy that used E(2) scores as a benchmark for remediation. A score of 850 was the most common E(2) benchmark designated by faculties, and students who failed to achieve the faculty-designated E(2) benchmark score were required to retest with a parallel version of the E(2). Remediation resources used to assist students in achieving faculty-designated E(2) benchmark scores varied widely, with many programs employing multiple remediation methods. PMID:23566508

Langford, Rae; Young, Anne

276

Performance Tested Method multiple laboratory validation study of ELISA-based assays for the detection of peanuts in food.  

PubMed

Performance Tested Method multiple laboratory validations for the detection of peanut protein in 4 different food matrixes were conducted under the auspices of the AOAC Research Institute. In this blind study, 3 commercially available ELISA test kits were validated: Neogen Veratox for Peanut, R-Biopharm RIDASCREEN FAST Peanut, and Tepnel BioKits for Peanut Assay. The food matrixes used were breakfast cereal, cookies, ice cream, and milk chocolate spiked at 0 and 5 ppm peanut. Analyses of the samples were conducted by laboratories representing industry and international and U.S governmental agencies. All 3 commercial test kits successfully identified spiked and peanut-free samples. The validation study required 60 analyses on test samples at the target level 5 microg peanut/g food and 60 analyses at a peanut-free level, which was designed to ensure that the lower 95% confidence limit for the sensitivity and specificity would not be <90%. The probability that a test sample contains an allergen given a prevalence rate of 5% and a positive test result using a single test kit analysis with 95% sensitivity and 95% specificity, which was demonstrated for these test kits, would be 50%. When 2 test kits are run simultaneously on all samples, the probability becomes 95%. It is therefore recommended that all field samples be analyzed with at least 2 of the validated kits. PMID:15759737

Park, Douglas L; Coates, Scott; Brewer, Vickery A; Garber, Eric A E; Abouzied, Mohamed; Johnson, Kurt; Ritter, Bruce; McKenzie, Deborah

277

A Reliability and Validity Study of the Cornell Scale among Elderly Inpatients, Using Various Clinical Criteria  

Microsoft Academic Search

Background: The validity of the Cornell Scale for Depression in Dementia is seldom studied in institutions. Method: Two reliability studies, with 103 and 32 patients, and a validity study with 231 patients in nursing homes and in hospital were performed. They were assessed by the Cornell Scale, Clinical Dementia Rating scale and Self-Maintenance scale. A psychiatrist ‘blind’ to the Cornell

Maria Lage Barca; Knut Engedal; Geir Selbæk

2010-01-01

278

40 CFR 152.93 - Citation of a previously submitted valid study.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Citation of a previously submitted valid study...Data Submitters' Rights § 152.93 Citation of a previously submitted valid study...submitter, no documentation other than the citation is necessary. (b) Study...

2013-07-01

279

40 CFR 152.93 - Citation of a previously submitted valid study.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Citation of a previously submitted valid study...Data Submitters' Rights § 152.93 Citation of a previously submitted valid study...submitter, no documentation other than the citation is necessary. (b) Study...

2011-07-01

280

41 CFR 60-3.5 - General standards for validity studies.  

Code of Federal Regulations, 2013 CFR

...through a construct validity study should consist of data showing...standardization. Validity studies should be carried out under...of time and in a majority of cases, progress to a higher level...when technically feasible, a study which is designed to...

2013-07-01

281

Validation studies based on critical experiments performed with fuel pin arrays moderated by Pu + U solutions  

SciTech Connect

This paper outlines the results of a calculational study that was performed to validate the SCALE computer code system using data from critical experiments performed with fuel pin arrays moderated by mixed Pu + U aqueous solutions. A companion paper describes the experiments and discusses the criticality data that were obtained. These experimental activities are part of a joint exchange program between the US Department of Energy (DOE) and the Power Reactor and Nuclear Fuel Development Corporation of Japan in the area of criticality data development. The Consolidated fuel Reprocessing Program (CFRP) at Oak Ridge National Laboratory (ORNL) manages the program for the DOE. The experiments were conducted at the Battelle Pacific Northwest Laboratories-Critical Mass Laboratory (PNL-CML).

Smolen, G.R.; Matsumoto, T. (Oak Ridge National Lab., TN (USA))

1989-01-01

282

Validation study of gas chromatographic determination of pentachlorophenol in animal liver  

SciTech Connect

A validation study was conducted of a gas chromatographic procedure for the determination of pentachlorophenol (PCP) in chicken, pork, and beef liver. Five analysts representing 5 laboratories analyzed randomly numbered blind duplicates at 3 fortified tissue concentrations and one incurred tissue on 2 consecutive days. The PCP concentrations ranged from approximately 40 to 400 parts per billion (ppb). All data were reported to 3 significant figures in ppb. The coefficients of variation for repeatability were between 2.8 and 8.5%, except for the beef liver, at a mean value of 80 ppb PCP, where the CV was 11.3%. The CVs for reproducibility were in the range of 9.7 - 16.5% with little significant difference by species. The CV asymptotically approached 10% as the PCP level increased.

Gillard, D.; Epstein, R.L.; Ashworth, R.B.; Curry, K.; Nathan, Q.

1988-01-01

283

An opportunistic validation of studies on the psychosocial benefits of blogging.  

PubMed

The authors conducted two studies on the characteristics of bloggers and the psychosocial effects of blogging, both published in CyberPsychology and Behavior. The publication of the first article attracted considerable multinational media attention with over 70 incidents of press coverage in the first 3 weeks after publication. As a consequence, commentary on the research emerged on 167 blogs in the same time period. Many of the comments surrounded the validity of the research findings, and thus an opportunity arose to re-evaluate the research outcomes based on the unsolicited responses posted by bloggers. This report outlines the methodology used to evaluate responses to the initial research, and discusses potential future applications of this approach. PMID:21117978

Baker, James R; Moore, Susan M

2010-11-30

284

Validating and Calibrating Agent-Based Models: A Case Study  

Microsoft Academic Search

In this paper we deal with some validation and calibration experiments on a modified version of the Complex Adaptive Trivial\\u000a System (CATS) model proposed in Gallegati et al. (2005 Journal of Economic Behavior and Organization, 56, 489–512). The CATS model has been extensively used to replicate a large number of scaling types stylized facts with a remarkable\\u000a degree of precision. For

Carlo Bianchi; Pasquale Cirillo; Mauro Gallegati; Pietro A. Vagliasindi

2007-01-01

285

MINET validation study using steam generator test data  

Microsoft Academic Search

Three steam generator transient test cases that were simulated using the MINET computer code are described, with computed results compared against experimental data. The MINET calculations closely agreed with the experiment for both the once-through and the U-tube steam generator test cases. The effort is part of an ongoing effort to validate the MINET computer code for thermal-hydraulic plant systems

G. J. Van Tuyle; J. G. Guppy

1984-01-01

286

Signs and Symptoms vs Nerve Conduction Studies to Diagnose Diabetic Sensorimotor Polyneuropathy  

PubMed Central

Introduction Test whether physicians can validly and reproducibly diagnose diabetic sensorimotor polyneuropathy (DSPN). Methods Twelve physicians assessed 24 patients with diabetes mellitus (DM) on consecutive days (576 examinations) with physical features and voice disguised. Results were compared to gold standard 75% group diagnosis and a nerve conduction score (? 5 NC nds). Results Masking of patients was achieved. Reproducibility measured by the kappa coefficient and compared to ? 5 NC nd varied considerably among physicians: median and ranges: signs 0.8 (0.32 to 1.0); symptoms 0.79 (0.36 to 1.0) and diagnoses 0.47 (0.33 to 0.84) – both low and high scores indicating poor performance. There was substantial agreement between 75% group dx and confirmed NC abnormality. As compared to ? 5 NC, individual physicians’ clinical diagnosis was excessively variable and frequently inaccurate. Discussion Study physician diagnosis from signs and symptoms were excessively variable, often over-estimating DSPN. Specific approaches to improving proficiency should be tested.

2010-01-01

287

CONTEXT OF USING RELIABILITY AND VALIDITY MEASURES - Relevance of correlation in the study of causation  

Microsoft Academic Search

The article describes the contexts of using measures of reliability and validity in management while specifying how these measures can enhance the results of studies that have a strong prescriptive component. Also, it is a synthetic study of strengths, weaknesses, and appropriateness of the correlation, surveys (survey research) and experimentation, which shows that measuring validity and fidelity is required for

Walter G. AMEDZRO ST-HILAIRE

288

Validity of the Sex-Role Egalitarianism Scale: Two replication studies  

Microsoft Academic Search

To enhance the construct validity of the Sex-Role Egalitarianism Scale (SRES), two replications of earlier validity studies were undertaken. Samples were from several college campuses and primarily Caucasian. In Study 1, multiple regression analyses confirmed a hypothesized curvilinear relationship between scores on the SRES and scores on the MacDonald Sex Role Survey, a measure of gender role ideology regarding women.

Lynda A. King; Daniel W. King; D. Bruce Carter; Carol Ryan Surface; Kim Stepanski

1994-01-01

289

Validity and Reproducibility of a Food Frequency Interview in a MultiCultural Epidemiologic Study  

Microsoft Academic Search

PURPOSE: There is limited support for the validity and reproducibility of dietary assessment in culturally diverse populations. The goal of this study was to evaluate the comparative validity and reproducibility of a Food Frequency Questionnaire (FFQ) used in the observational, multi-cultural Insulin Resistance Atherosclerosis Study (IRAS).METHODS: Women (n = 186) were approximately equally distributed by ethnicity from one urban center

Elizabeth J Mayer-Davis; Mara Z Vitolins; Suzan L Carmichael; Sandra Hemphill; Georgia Tsaroucha; Julia Rushing; Sarah Levin

1999-01-01

290

40 CFR 152.93 - Citation of a previously submitted valid study.  

Code of Federal Regulations, 2010 CFR

An applicant may demonstrate compliance for a data requirement by citing a valid study previously submitted to the Agency. The study is not to be submitted to the Agency with the application. (a) Study originally submitted by the...

2012-07-01

291

The Addiction Severity Index A field study of internal consistency and validity  

Microsoft Academic Search

This study investigated whether the use of the Addiction Severity Index (ASI) in a network of inner-city alcohol and drug abuse clinics under nonideal conditions would yield internally consistent and valid data. A sample of 8,984 ASI scores was collected over a 34-month period. Construct validity was examined by computing the internal consistency of all subscales. Convergent and divergent validity

Christoph Leonhard; Kevin Mulvey; David R. Gastfriend; Michael Shwartz

2000-01-01

292

Effective medium theory in studies of conductivity of composite polymeric electrolytes  

Microsoft Academic Search

The application of effective medium theory to a description of a temperature and composition dependence of conductivity of composite polymeric electrolytes is presented. Conductivities of several composite systems containing conducting (NASICON) or nonconducting (?-Al2O3, polyacrylamide) additives are analyzed in terms of effective medium theory approaches. All of the systems studied are based on polyether matrices. The influence of grain size

J. Przyluski; M. Siekierski; W. Wieczorek

1995-01-01

293

Tracking Study for Top-off Safety Validation at SSRL  

SciTech Connect

A tracking study was performed at SSRL to identify necessary controls and to prove the safety of top-off operation from radiation hazard under such conditions. The safety rationale, tracking setup and the results are presented. Top-off operational mode has become a trend for existing and planned third-generation storage ring light sources for the many benefits such as increased average brightness, improved thermal stability and elimination of the interruption to user experiments due to traditional injection [1, 2]. Unlike the traditional decay mode injection which happens a few times a day and during which the photon beamline shutters are closed, top-off mode injection requires photon beamline shutters to remain open during injection and occurs much more frequently, from once every 5 seconds to once every 30 minutes. Therefore injection may be transparent to user experiments and the stored current variation can be significantly reduced. For a facility equipped with a full-energy injector, the biggest challenge to the implementation of the top-off mode may be the control of radiation hazard. Studies at ALS and SSRL [2, 3] have shown that a single injected electron pulse that enters the photon beamline and exits the radiation shield wall would cause unacceptable radiation doses on the experimental floor. For the protection of users and experimental equipment, it is hence a prerequisite for top-off operation to establish controls that absolutely prevent such occurrences. Similar to other facilities such as ALS and APS [2, 4], tracking simulations were conducted at SSRL to identify the control measures, define the specifications and prove the radiation safety. However, a different approach toward the proof of safety is taken at SSRL. In this paper we first describe the SSRL accelerator complex with emphasis on the aspects related to top-off in section 2. The general considerations and requirements for top-off are presented in section 3. Section 4 and 5 give a detailed description of the tracking setup and results. Concluding remarks are given in section 6.

Huang, Xiaobiao

2011-08-19

294

The federal Post Conviction Risk Assessment (PCRA): a construction and validation study.  

PubMed

Offender assessment has been and remains the cornerstone of effective community supervision. This article presents the development of and tests the predictive validity of a 4th-generation risk assessment instrument designed for U.S. probation. A large administrative data set was used to create the assessment instrument and conduct an initial validation. Subsequent data generated from officer-completed assessments were used to conduct a prospective validation. Finally, data from case vignettes scored by trained officers were used to test the interrater agreement of the assessment instrument. Overall, analysis revealed that the assessment instrument predicted rearrest reliably when using the assessment results based on administrative data or officer-completed assessments. Analysis also revealed high rates of interrater agreement. Recommendations for future research and policy implications are presented. PMID:23148771

Lowenkamp, Christopher T; Johnson, James L; Holsinger, Alexander M; Vanbenschoten, Scott W; Robinson, Charles R

2012-11-12

295

Electric conduction mechanism in conjugated polymers studied using flicker noise spectroscopy  

Microsoft Academic Search

Spectroscopy of Stochastic Signals (3S) has been used to study conduction behavior in electrochemically deposited conductive polymers (CP) using as example polyaniline and poly(3-methyl thiophene). Within the 3S approach, the conduction process is considered as a stochastic process in heterogeneous disordered system rather than as some classical conduction mechanisms like Schottky or Poole-Frenkel emission. We have been able to distinguish

Vitali P. Parkhutik; Rahul Patil; Yutaka Harima

2003-01-01

296

Effect of Filling Material on the Temperature Distribution in a Thermal Conductivity Probe and Thermal Conductivity Measurements: A Numerical Study. (Reannouncement with New Availability Information).  

National Technical Information Service (NTIS)

A numerical investigation taking into account the composite nature of a line thermal conductivity probe was carried out using a finite-difference technique, to study the temperature distribution inside a thermal conductivity probe for different filling ma...

M. V. Karwe C. H. Tong

1992-01-01

297

Correlational, Comparative Study: What is a Valid Research Design?  

Microsoft Academic Search

Many social gerontologists have been involved lately in correlational and\\/or comparative research activities to advance their professional knowledge and explore social facts and realities about the aging world. Conducting this kind of research requires social gerontologists to pay proper attention to the formation of comparison groups and to the explanation of findings. They have to deal with the issue of

Jik-Joen Lee

2007-01-01

298

Conductivity studies on PEMA based polymer electrolyte system with LiClO4 salt  

NASA Astrophysics Data System (ADS)

The present work describes the surface and conductivity studies on PEMA based polymer electrolytes prepared by solvent casting technique. Polymer electrolytes were characterized by SEM and conductivity studies. The maximum ionic conductivity value is found to be 2.0245 × 10-5 Scm-1 at 303K for PEMA (25wt %)-LiClO4 (8wt %)-EC (67wt %) electrolyte system. Surface morphology was examined from scanning electron microscopic studies.

Rajendran, S.; Senthil, K.; Kesavan, K.; Mathew, Chithra M.; Mahalingam, T.

2013-02-01

299

Experimental and numerical study of the effective thermal conductivity of silica nanocomposites with thermal boundary resistance  

SciTech Connect

The thermal interface resistance at the macro scale is mainly described by the physical gap between two interfaces and constriction resistance due to this gap. The small gaps between the two material faces makes up the majority of thermal interface resistance at the macro scale. So, most of the studies have been focused on characterizing effect of surface geometry and material properties to thermal interface resistance. This resistance is more widely known as thermal contact resistance, represented with Rc. There are various models to predict thermal contact resistance at macro scale. These models predict thermal resistance Rc for given two materials by utilizing their bulk thermomechanical properties. Although, Rc represents thermal resistance accurately for macro size contacts between two metals, it is not suitable to describe interface resistance of particles in modern TIMs, aka particulate composites. The particles inside recently available TIMs are micron size and with effort to further increase surface area this particle size is approaching nano scale. At this small scale, Rc does not accurately predict thermal interface, as it is very difficult to characterize the surface topography. The thermal discontinuity at perfectly bonded interface of two dissimilar materials is termed as thermal boundary resistance (Rb) or Kapitza resistance. The macroscopic assumptions that thermal discontinuity only exists due to gaps and surface geometry leads to substantial error in determining interface thermal properties at micron and nano scale. The phenomenon of thermal boundary resistance is an inherent material property and arises due to fundamental mechanism of thermal transport. For metal-matrix particulate composites, Rb plays more important role than Rc. The free flowing nature of the polymer would eliminate most of the gaps between the two materials at their interface. This means almost all of the thermal resistance at particle/matrix interface would occur due to Rb. The current study presents experimental study of thermal boundary resistance for silica nano particles embedded inside epoxy resin. The bulk conductivity of the sample is measured and Rc is back calculated using Hasselman-Johnson s (H-J) equation. The numerical validation of the equation is also presented, including extrapolation study to predict effective conductivity of the nanocomposite TIM.

Kothari, Rushabh M [ORNL; Dinwiddie, Ralph Barton [ORNL; Wang, Hsin [ORNL

2013-01-01

300

Selection of test chemicals for the ECVAM international validation study on in vitro embryotoxicity tests. European Centre for the Validation of Alternative Methods.  

PubMed

The European Centre for the Validation of Alternative Methods (ECVAM) has sponsored a large international prevalidation and validation study of three embryotoxicity tests, involving embryonic stem cells, limb bud micromass cultures, and post-implantation whole-embryo cultures. The main objective of the study was to assess the performance of these in vitro tests in discriminating between non-embryotoxic, weakly embryotoxic and strongly embryotoxic compounds. An initial part of the study was to select 20 test substances for the formal validation trial, conducted under blind conditions. A database of in vivo and in vitro developmental toxicity test results was complied on 310 chemicals that had been used in previous validation studies, or suggested for such use, or that had good quality "segment II"-type in vivo data, or for which there were human data. From this database, a shortlist of about 30 candidates was constructed. Because the ECVAM study would not include metabolic activation, chemicals known to require activation for their developmental effects were excluded as candidates, although some known stable metabolites were included. Attempts were made: to include substances of diverse mechanism; to avoid overemphasis on pharmaceuticals; to avoid biologically inert substances as non-embryotoxicants; and to make the list different from those used previously. The candidates were of three categories: Class 3, strongly embryotoxic, was defined as developmentally toxic in all species tested, inducing multiple developmental effects, and with a high A/D ratio. Class 1, non-embryotoxic, was defined as not developmentally toxic at maternally toxic exposures, but which may show some minor embryo/fetal toxicity, which cannot be separated from maternal toxicity. Class 2, weakly embryotoxic, were chemicals of intermediate activity. From this candidate list, chemicals of known receptor (androgen, oestrogen, glucocorticoid, aryl hydrocarbon) mechanisms were excluded, on the basis that simple tests for such activity are already available. In addition, chemicals not freely available were excluded, and an emphasis on human data was applied. The final list of 20 chemicals was: Class 3--6-aminonicotinamide, 5-bromo- 2'-deoxyuridine, hydroxyurea, methylmercury chloride, methotrexate, all-trans-retinoic acid; Class 2--boric acid, dimethadione, lithium chloride, methoxyacetic acid, valproic acid (VPA), 2-propyl-4-pentynoic acid (4-yn-VPA), salicylic acid sodium salt; and Class 1--acrylamide, D-(+)-camphor, dimethyl phthalate, diphenhydramine hydrochloride, 2-ethyl-4- methylpentanoic acid (isobutyl-ethyl-VPA), Penicillin G sodium salt, saccharin sodium hydrate. PMID:11971754

Brown, Nigel A

301

What Forty Years of Research Says about the Impact of Technology on Learning: A Second-Order Meta-Analysis and Validation Study  

ERIC Educational Resources Information Center

|This research study employs a second-order meta-analysis procedure to summarize 40 years of research activity addressing the question, does computer technology use affect student achievement in formal face-to-face classrooms as compared to classrooms that do not use technology? A study-level meta-analytic validation was also conducted for…

Tamim, Rana M.; Bernard, Robert M.; Borokhovski, Eugene; Abrami, Philip C.; Schmid, Richard F.

2011-01-01

302

What Forty Years of Research Says about the Impact of Technology on Learning: A Second-Order Meta-Analysis and Validation Study  

ERIC Educational Resources Information Center

This research study employs a second-order meta-analysis procedure to summarize 40 years of research activity addressing the question, does computer technology use affect student achievement in formal face-to-face classrooms as compared to classrooms that do not use technology? A study-level meta-analytic validation was also conducted for purposes…

Tamim, Rana M.; Bernard, Robert M.; Borokhovski, Eugene; Abrami, Philip C.; Schmid, Richard F.

2011-01-01

303

Boundary layer study. Phase 4: Experimental validation test plan  

NASA Astrophysics Data System (ADS)

The trend towards very large area ratio nozzles, which result in performance gains for space propulsion applications, has increased the need for detailed knowledge of the momentum losses due to nozzle viscous effects (i.e., boundary layer). These losses degrade overall system performance, such as increasing system weight, decreasing useful payload weight, and/or decreasing effective system range. Another important factor in designing propulsive nozzles is the detailed knowledge of heat transfer at the wall for regeneratively cooled walls and/or material performance. Phase 4 (described in this report) consists of preparing an experimental test plan, which, if executed, would validate computational techniques used in evaluating propulsion performance losses due to boundary layers in rocket nozzles. The importance of the loss and the basis for the experimental work are established. Experimental techniques are also reviewed. Visits to numerous experimental facilities are described along with recommendations from these facilities. Finally, recommendations as to the diagnostic techniques of choice are made.

Kehtarnavaz, H.; Coats, D. E.

1990-11-01

304

Towards a standard procedure for validation of satellite-derived cloud liquid water path: a study with SEVIRI data  

Microsoft Academic Search

Differences between satellite-derived and ground-based values of cloud liquid water path (LWPsat and LWPgr) in validation studies are partly caused by issues associated with the validation itself, in particular scale differences and the parallax. We have performed calculations aiming at establishing standards for validation procedures so that contributions to the differences by the validation issues are minimized. To study this

W. Greuell; R. A. Roebeling

2009-01-01

305

A Collection of Studies Conducted in Education about "Global Warming" Problem  

ERIC Educational Resources Information Center

|The studies global warming problem conducted in education discipline in the world and in Turkey were analysed for this study. The literature was reviewed extensively especially through the articles in the indexed journals of Ebsco Host, Science Direct, Taylor and Francis and Web of Science databases and this study was conducted according to the…

Bozdogan, Aykut Emre

2011-01-01

306

40 CFR 790.62 - Submission of study plans and conduct of testing.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Submission of study plans and conduct of testing. 790...Agreements § 790.62 Submission of study plans and conduct of testing. (a...pursuant to a consent agreement shall submit a study plan no later than 45 days prior to...

2013-07-01

307

Validation of a Computerized Cognitive Assessment System for Persons with Stroke: A Pilot Study  

ERIC Educational Resources Information Center

|This study investigates the validity of a newly developed computerized cognitive assessment system (CCAS) that is equipped with rich multimedia to generate simulated testing situations and considers both test item difficulty and the test taker's ability. It is also hypothesized that better predictive validity of the CCAS in self-care of persons…

Yip, Chi Kwong; Man, David W. K.

2009-01-01

308

Person Fit and Criterion-Related Validity: An Extension of the Schmitt, Cortina, and Whitney Study.  

ERIC Educational Resources Information Center

|Studied the effect on criterion-related validity of nonfitting response vectors (NRVs) on a predictor test using simulation. Results suggest that NRVs can influence the validity of a test if the type of misfit is severe, the correlation between the predictor and criterion scores is "p"=0.3 or 0.4, and there are 15% or higher NRVs. (SLD)|

Meijer, Rob R.

1997-01-01

309

VALIDATION STUDY OF A HPLC METHOD ABLE TO MEASURE BIOGENIC AMINES IN CHICKEN MEAT  

Microsoft Academic Search

The work describes an internal study for validating the measuring method of the biogenic amines in refrigerated chicken meat by means of the high performance liquid chromatography (HPLC). The evaluated features for validating the measuring method by means of the high performance liquid chromatography are as follows: linearity, precision, accuracy (repeatability and reproductibility), selectivity, sensitivity (detection limit, quantification limit), robustness.

Octavian BASTON; Alexandru Lucian STROIA; Daniela MOISE; Octavian BARNA

310

Factorial and Discriminant Validity of the Center for Epidemiological Studies Depression (CES-D) Scale.  

ERIC Educational Resources Information Center

|Examined the factorial and discriminant validity of the Center for Epidemiological Studies Depression (CES-D) scale for 116 parents participating in family support programs. Factorial validity was adequate, and results indicated a moderate correlation between the CES-D and self-esteem and state anxiety. However, a high correlation was obtained…

Orme, John G.; And Others

1986-01-01

311

Validating the Center for Epidemiological Studies Depression Scale for Children in Rwanda  

ERIC Educational Resources Information Center

Objective: We assessed the validity of the Center for Epidemiological Studies Depression Scale for Children (CES-DC) as a screen for depression in Rwandan children and adolescents. Although the CES-DC is widely used for depression screening in high-income countries, its validity in low-income and culturally diverse settings, including sub-Saharan…

Betancourt, Theresa; Scorza, Pamela; Meyers-Ohki, Sarah; Mushashi, Christina; Kayiteshonga, Yvonne; Binagwaho, Agnes; Stulac, Sara; Beardslee, William R.

2012-01-01

312

Validating teaching competencies for graduate teaching assistants: A national study using the Delphi method  

Microsoft Academic Search

In this study the Delphi Method was used to validate teaching competencies of graduate teaching assistants (TAs). Through the use of expert opinion, a panel of national leaders in teaching assistant support and training validated twenty six competencies as important in the preparation of teaching assistants. Feedback from panelists suggested that some instructional competencies depend on the specific responsibilities that

Ronald D. Simpson; Kathleen S. Smith

1993-01-01

313

The Early Maladaptive Schema Questionnaire-Short Form: A Construct Validity Study.  

ERIC Educational Resources Information Center

N.B. Schmidt, T.E. Joiner, J.E. Young, and M.J. Telch (1995) provided preliminary construct validity for scores from J.E. Young's (1990) 205-item Early Maladaptive Schema Questionnaire. The present study extends this work by examining the construct validity of scores from the shorter 75-item version of this instrument-the Early Maladaptive Schema…

Glaser, Brian A.; Campbell, Linda F.; Calhoun, Georgia B.; Bates, Jeffrey M.; Petrocelli, John V.

2002-01-01

314

Continuous and Collaborative Validation: A Field Study of Requirements Knowledge in Agile  

Microsoft Academic Search

We present the results of our field study that describe how requirements validation was performed at an industrial software company using agile software practices. As is common in agile processes, the team did not capture requirements knowledge in a comprehensive specification document. Instead, requirements knowledge was captured in user stories, automated acceptance tests, personal notes, and conversations. Validation was performed

Rosalva E. Gallardo-Valencia; Susan Elliott Sim

2009-01-01

315

Validation Studies of the Behavioral Risk Factor Surveillance System- New Walking Module  

Cancer.gov

Validation Studies of the Behavioral Risk Factor Surveillance System- New Walking Module Yore et al. 2004 (Abstract) See reference #17 Methods Relationships between BRFSSA PA module and activity logs in two studies: 1) Participants answered the survey

316

21 CFR 312.120 - Foreign clinical studies not conducted under an IND.  

Code of Federal Regulations, 2013 CFR

...data from a foreign clinical study not conducted under an IND...the protocol and results of the study and, should FDA request, case records maintained by the investigator...and drug product used in the study, including a description...

2013-04-01

317

Estimating the Validity of the Guilty Knowledge Test From Simulated Experiments: The External Validity of Mock Crime Studies  

Microsoft Academic Search

This experiment was designed to examine the external validity of the standard mock-crime procedure used extensively to evaluate the validity of polygraph tests. The authors manipulated the type of mock-crime procedure (standard vs. a more realistic version) and the time of test (immediate vs. delayed) and examined their effects on the validity of the Guilty Knowledge Test (GKT) and the

David Carmel; Eran Dayan; Ayelet Naveh; Ori Raveh; Gershon Ben-Shakhar

2003-01-01

318

Study on the thermal conductivity and microstructure of silicon nitride used for power electronic substrate  

Microsoft Academic Search

The thermal conductivity and microstructure of Si3N4 ceramics used for power electronic substrate were studied in present paper. Thermal conductivity of Si3N4 ceramics sintered at different temperatures varied greatly. The microstructure of the specimens was studied with X-ray diffraction, EDS and transmission electronic microscope to reveal the difference in thermal conductivity. The experimental results showed that microstructure of Si3N4 ceramics

Wei Xu; Xiao-shan Ning; He-ping Zhou; Yuan-bo Lin

2003-01-01

319

Conductance deep-level transient spectroscopic study of anomalous hole trap in GaAs MESFETs  

Microsoft Academic Search

The anomalous `hole' trap like peaks observed in conductance DLTS spectra of GaAs MESFETs have been previously studied and have been associated with surface states present in the ungated regions at the GaAs-passivant interface. Besides these peaks, the conductance DLTS study of thermal emission and capture by these interface traps also indicates the presence of an associated surface conducting layer.

V. R. Balakrishnan; Vikram Kumar; Subhasis Ghosh

1998-01-01

320

Electric conduction mechanism in conjugated polymers studied using flicker noise spectroscopy  

NASA Astrophysics Data System (ADS)

Spectroscopy of Stochastic Signals (3S) has been used to study conduction behavior in electrochemically deposited conductive polymers (CP) using as example polyaniline and poly(3-methyl thiophene). Within the 3S approach, the conduction process is considered as a stochastic process in heterogeneous disordered system rather than as some classical conduction mechanisms like Schottky or Poole-Frenkel emission. We have been able to distinguish several modes of the conduction process in conducting polymers using the 3S methodology. Particularly, we have established that the transport of charge carriers in highly doped CPs is much less correlated than in non-doped ones, that is, at low doping levels elementary processes involved in the conduction are more correlated than in highly doped polymer. By increasing applied electric field we also achieve lower correlation in a sequence of elementary events contributing to the conductivity of CP. Apparently, the change in the correlation length corresponds to changing mechanism of the electrical conduction. The lower correlation in highly doped sample can be attributed to various factors including change in CP conformation, enhancement in inter-chain charge transfer and generation of polaron lattice. The obtained results show the high informative potential of the 3S method in studying conduction mechanism in conducting polymers.

Parkhutik, Vitali P.; Patil, Rahul; Harima, Yutaka

2003-05-01

321

Multiresidue gas chromatographic method for determining organochlorine pesticides in meats: validation study for swine and beef fats.  

PubMed

A validation of a previously studied method for determining organochlorine residues in poultry fat was conducted to extend the usefulness of the method to beef and swine fats. The validation samples consisted of 16 materials all analyzed in duplicate. Fortification levels ranged from 0.02 to 1.2 ppm for alpha-BHC, lindane, cis- and trans-chlordane, octachlor epoxide, o,p'- and p,p'-DDT, p,p'-DDE, p,p'-TDE, hexachlorobenzene, heptachlor epoxide, dieldrin, endrin, methoxychlor, mirex, and toxaphene. The average recovery was 101% with a range of 79-113%, not including toxaphene. The ranges of coefficients of variation were CVo = 0-23.37% and CVx = 3.74-26.19%. The results were comparable to the previous collaborative study of the same method for poultry fat. The extended method has been adopted official first action. PMID:4055641

Ault, J A; Spurgeon, T E; Gillard, D S; Mallinson, E T

322

Diagnosis of depression among adolescents - a clinical validation study of key questions and questionnaire  

PubMed Central

Background The objective of the study is to improve general practitioners' diagnoses of adolescent depression. Major depression is ranked fourth in the worldwide disability impact. Method/Design Validation of 1) three key questions, 2) SCL-dep6, 3) SCL-10, 4) 9 other SCL questions and 5) WHO-5 in a clinical study among adolescents. The Composite International Diagnostic Interview (CIDI) is to be used as the gold standard interview. The project is a GP multicenter study to be conducted in both Norway and Denmark. Inclusion criteria are age (14–16) and fluency in the Norwegian and Danish language. A number of GPs will be recruited from both countries and at least 162 adolescents will be enrolled in the study from the patient lists of the GPs in each country, giving a total of at least 323 adolescent participants. Discussion The proportion of adolescents suffering from depressive disorders also seems to be increasing worldwide. Early interventions are known to reduce this illness. The earlier depression can be identified in adolescents, the greater the advantage. Therefore, we hope to find a suitable questionnaire that could be recommended for GPs.

Haavet, Ole R; Christensen, Kaj S; Sirpal, Manjit K; Haugen, Wenche

2007-01-01

323

Perceived Stress Scale: Reliability and Validity Study in Greece  

PubMed Central

Objective: To translate the Perceived Stress Scale (versions PSS-4, ?10 and ?14) and to assess its psychometric properties in a sample of general Greek population. Methods: 941 individuals completed anonymously questionnaires comprising of PSS, the Depression Anxiety and Stress scale (DASS-21 version), and a list of stress-related symptoms. Psychometric properties of PSS were investigated by confirmatory factor analysis (construct validity), Cronbach’s alpha (reliability), and by investigating relations with the DASS-21 scores and the number of symptoms, across individuals’ characteristics. The two-factor structure of PSS-10 and PSS-14 was confirmed in our analysis. We found satisfactory Cronbach’s alpha values (0.82 for the full scale) for PSS-14 and PSS-10 and marginal satisfactory values for PSS-4 (0.69). PSS score exhibited high correlation coefficients with DASS-21 subscales scores, meaning stress (r = 0.64), depression (r = 0.61), and anxiety (r = 0.54). Women reported significantly more stress compared to men and divorced or widows compared to married or singled only. A strong significant (p < 0.001) positive correlation between the stress score and the number of self-reported symptoms was also noted. Conclusions: The Greek versions of the PSS-14 and PSS-10 exhibited satisfactory psychometric properties and their use for research and health care practice is warranted.

Andreou, Eleni; Alexopoulos, Evangelos C.; Lionis, Christos; Varvogli, Liza; Gnardellis, Charalambos; Chrousos, George P.; Darviri, Christina

2011-01-01

324

Validation of extravascular lung water measurement by single transpulmonary thermodilution: human autopsy study  

PubMed Central

Introduction Gravimetric validation of single-indicator extravascular lung water (EVLW) and normal EVLW values has not been well studied in humans thus far. The aims of this study were (1) to validate the accuracy of EVLW measurement by single transpulmonary thermodilution with postmortem lung weight measurement in humans and (2) to define the statistically normal EVLW values. Methods We evaluated the correlation between pre-mortem EVLW value by single transpulmonary thermodilution and post-mortem lung weight from 30 consecutive autopsies completed within 48 hours following the final thermodilution measurement. A linear regression equation for the correlation was calculated. In order to clarify the normal lung weight value by statistical analysis, we conducted a literature search and obtained the normal reference ranges for post-mortem lung weight. These values were substituted into the equation for the correlation between EVLW and lung weight to estimate the normal EVLW values. Results EVLW determined using transpulmonary single thermodilution correlated closely with post-mortem lung weight (r = 0.904, P < 0.001). A linear regression equation was calculated: EVLW (mL) = 0.56 × lung weight (g) - 58.0. The normal EVLW values indexed by predicted body weight were approximately 7.4 ± 3.3 mL/kg (7.5 ± 3.3 mL/kg for males and 7.3 ± 3.3 mL/kg for females). Conclusions A definite correlation exists between EVLW measured by the single-indicator transpulmonary thermodilution technique and post-mortem lung weight in humans. The normal EVLW value is approximately 7.4 ± 3.3 mL/kg. Trial registration UMIN000002780.

2010-01-01

325

A Set of Principles for Conducting and Evaluating Interpretive Field Studies in Information Systems  

Microsoft Academic Search

This article discusses the conduct and evaluation of interpretive research in information systems. While the conventions for evaluating information systems case studies conducted according to the natural science model of social science are now widely accepted, this is not the case for interpre- tive field studies. A set of principles for the con- duct and evaluation of interpretive field research

Heinz K. Klein; Michael D. Myers

1999-01-01

326

Effect of isotopic purity on thermal conductivity of boron nitride: A theoretical study  

NASA Astrophysics Data System (ADS)

In this letter we report the theoretical study of the effect of isotopic purity on the temperature dependence of the lattice thermal conductivity of cubic BN single crystals. The maximum thermal conductivity of pure BN is very high (~105 W/m/K) and it is comparable to the thermal conductivity of the carbon nanotube. It is two orders of magnitude higher than that of BN with 50%10B. We find that the very high contribution (~ 95%) of the usually neglected N-drift scattering at the thermal conductivity peak is the reason for such an increase in thermal conductivity of pure BN, compared to that of natural BN. The thermal conductivity is nearly symmetric with respect to the isotopic composition of boron and it is minimum for 50%10B and 50%11B. The role of phonon scattering by boron isotopes present in BN, in controlling the temperature dependence of thermal conductivity has been accurately quantified.

Barman, Saswati

2011-10-01

327

Validation Studies of the Physical Activity Scale for the Elderly (PASE)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

328

Validation Studies of the The Telephone Assessment of Physical Activity (TAPA)  

Cancer.gov

Validation Studies of the The Telephone Assessment of Physical Activity (TAPA) Mayer et al. 2008 See reference #98 Methods TAPA compared with the Rapid Assessment of Physical Activity questionnaire (RAPA) and the Community Healthy Activities Model Program

329

Validation Studies of the Finnish Multidimensional Health Assessment Questionnaire (MDHAQ) and Finnish Health Assessment Questionnaire (HAQ)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

330

Validation Studies of the Finnish Multidimensional Health Assessment Questionnaire (MDHAQ) and Finnish Health Assessment Questionnaire (HAQ)  

Cancer.gov

Validation Studies of the Finnish Multidimensional Health Assessment Questionnaire (MDHAQ) and Finnish Health Assessment Questionnaire (HAQ) Arkela-Kautiainen et al. 2005 See reference #75 Methods Relation between the Finnish MDHAQ (Finn-MDHAQ) function

331

Validation Studies of the The Short Questionnaire to assess Health–enhancing Physical activity (SQUASH)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

332

Validation Studies of the Ainsworth New Physical Activity Questionnaire (N-PAQ)  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

333

Validation Studies of the International Physical Activity Questionnaire (IPAQ) Short, Last 7-day  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

334

Validation Studies of the Two Question and Three Question Physical Activity Assessment  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

335

Validation Studies of the The Short Questionnaire to assess Health–enhancing Physical activity (SQUASH)  

Cancer.gov

Validation Studies of the The Short Questionnaire to assess Health–enhancing Physical activity (SQUASH) Wendel-Vos et al. 2003 See reference #65 Methods Relationship between SQUASH and CSA Activity Monitor (Spearman correlations) Sample 36 men and 14

336

Validation Studies of the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire  

Cancer.gov

Validation Studies of the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire Cyarto et al. 2006 See reference #77 Methods Correlations between the CHAMPS scores and tests of physical ability (physical performance measures PPM)

337

Validation Studies of the The Modifiable Activity Questionnaire (MAQ)/Pima Indian Questionnaire  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

338

Ride Qualities Criteria Validation/Pilot Performance Study: Flight Simulator Results.  

National Technical Information Service (NTIS)

Pilot performance was studied during simulated manual terrain following flight for ride quality criteria validation. An existing B-1 simulation program provided the data for these investigations. The B-1 simulation program included terrain following fligh...

L. U. Nardi H. Y. Kawana C. J. Borland N. M. Lefritz

1976-01-01

339

Tree Canopy Characterization for EO-1 Reflective and Thermal Infrared Validation Studies: Rochester, New York.  

National Technical Information Service (NTIS)

The tree canopy characterization presented herein provided ground and tree canopy data for different types of tree canopies in support of EO-1 reflective and thermal infrared validation studies. These characterization efforts during August and September o...

J. R. Ballard J. A. Smith

2002-01-01

340

Validation Studies of the National Health Interview Survey (NHIS)-walking questions  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Standardized Questionnaires of Walking & Bicycling Database: Introduction PAQ Walking & Bicycling Items Reference List PAQ Validation Studies References Summary Tables Search

341

Validation Studies of the Two Question and Three Question Physical Activity Assessment  

Cancer.gov

Validation Studies of the Two Question and Three Question Physical Activity Assessment Smith et al. 2005 See reference #106 Methods (2Q) and three-question (3Q) assessments compared to Active Australia Questionnaire (AAQ), and 7-day CSA accelerometer

342

A Belgian study on the reliability and relative validity of the Health Behaviour in School-Aged Children food-frequency questionnaire  

Microsoft Academic Search

Objective: In the Health Behaviour in School-Aged Children (HBSC) survey, the frequency of consumption of a limited number of food items - focusing on fibre, calcium and less healthy items - is queried using a 15-item food-frequency questionnaire (FFQ). The present study was conducted to assess the reliability and relative validity of the HBSC FFQ among school pupils in Belgium.

Carine A Vereecken; Lea Maes

2003-01-01

343

Concurrent validity of the CAGE questionnaire. The Nord-Trøndelag Health Study  

Microsoft Academic Search

The aim of this study was to examine the psychometric properties of the CAGE questionnaire, and the questionnaire's concurrent validity with current and previous alcohol consumption. This study employed data from the Nord-Trøndelag Health Survey wave 1 (HUNT-1 in 1984–86: N=24,900) and wave 2 (HUNT-2 in 1995–97: N=36,350). The concurrent validity of the CAGE questionnaire was examined both as a

Jens Christoffer Skogen; Simon Øverland; Ann Kristin Knudsen; Arnstein Mykletun

2011-01-01

344

Reproducibility and Validity of the Shanghai Women's Health Study Physical Activity Questionnaire  

Microsoft Academic Search

In this investigation, the authors evaluated the reproducibility and validity of the Shanghai Women's Health Study (SWHS) physical activity questionnaire (PAQ), which was administered in a cohort study of approximately 75,000 Chinese women aged 40-70 years. Reproducibility (2-year test-retest) was evaluated using kappa statistics and intraclass correlation coefficients (ICCs). Validity was evaluated by comparing Spearman correlations (r) for the SWHS

Charles E. Matthews; Xiao-Ou Shu; Gong Yang; Fan Jin; Barbara E. Ainsworth; Dake Liu; Yu-Tang Gao; Wei Zheng

2003-01-01

345

Use of a food frequency questionnaire in American Indian and Caucasian pregnant women: a validation study  

Microsoft Academic Search

BACKGROUND: Food frequency questionnaires (FFQs) have been validated in pregnant women, but few studies have focused specifically on low-income women and minorities. The purpose of this study was to examine the validity of the Harvard Service FFQ (HSFFQ) among low-income American Indian and Caucasian pregnant women. METHODS: The 100-item HSFFQ was administered three times to a sample of pregnant women,

Heather J Baer; Robin E Blum; Helaine RH Rockett; Jill Leppert; Jane D Gardner; Carol W Suitor; Graham A Colditz

2005-01-01

346

Experimental study of thermal conductivity of refrigerant R-409A in vapor phase  

NASA Astrophysics Data System (ADS)

Thermal conductivity of refrigerant R-409A in vapor phase was studied in the range of temperatures 306-425 K and pressures 0.12-1.33 MPa. Measurements were performed with the stationary method of coaxial cylinders. Uncertainty of experimental data on thermal conductivity was 1.5-2.5 %, and errors of temperature and pressure measurements did not exceed 0.05 K and 4 kPa, respectively. Approximating dependence of thermal conductivity on pressure and temperature was obtained. Thermal conductivity on dew line and in ideal gas state was calculated.

Verba, O. I.; Raschektaeva, E. P.; Stankus, S. V.

2011-12-01

347

Conductivity of nanosecond discharges in nitrogen and sulfur hexafluoride studied by particle-in-cell simulations  

SciTech Connect

The conductivity of the discharge gap during the nanosecond high-voltage pulsed discharge in nitrogen and sulfur hexafluoride is studied using particle-in-cell numerical simulations. It is shown that the conductivity in different locations of the cathode-anode gap is not uniform and that the conductivity is determined by both the runaway and the plasma electrons. In addition, it is shown that runaway electrons generated prior to the virtual cathode formation pre-ionize the discharge gap, which makes it conductive.

Levko, D.; Gurovich, V. Tz.; Krasik, Ya. E. [Department of Physics, Technion, 32000 Haifa (Israel)

2012-06-15

348

Standardized classroom management program: Social validation and replication studies in Utah and Oregon.  

PubMed

A comprehensive validation study was conducted of the Program for Academic Survival Skills (PASS), a consultant-based, teacher-mediated program for student classroom behavior. The study addressed questions related to: (a) brief consultant training, (b) subsequent teacher training by consultants using PASS manuals, (c) contrasts between PASS experimental teachers and students and equivalent controls on measures of teacher management skills, student classroom behavior, teacher ratings of student problem behaviors, and academic achievement, (d) reported satisfaction of participants, and (e) replication of effects across two separate school sites. Results indicated that in both sites significant effects were noted in favor of the PASS experimental group for (a) teacher approval, (b) student appropriate classroom behavior, and (c) four categories of student inappropriate behavior. Program satisfaction ratings of students, teachers, and consultants were uniformly positive, and continued use of the program was reported a year later. Discussion focused upon issues of cost-effectiveness, differential site effects, and the relationship between appropriate classroom behavior and academic achievement. PMID:16795604

Greenwood, C R; Hops, H; Walker, H M; Guild, J J; Stokes, J; Young, K R; Keleman, K S; Willardson, M

1979-01-01

349

Making Cartel Conduct Criminal: A Case Study of Ambiguity in Controlling Business Behaviour  

Microsoft Academic Search

This article explores the regulation of cartel conduct in Australia focusing, in particular, on the recent decision to criminalise so-called ‘hard-core’ cartels. It illuminates three interdependent ambiguities in regulating such conduct: economic, moral and legal. The case study is drawn on to highlight the challenges for the criminal law in attempting to resolve such ambiguities or tensions as they arise

Caron Beaton-Wells; Fiona Haines

2009-01-01

350

Conductance study of the thermodynamics of micellization of 1-hexadecylpyridinium bromide in (water + cosolvent)  

Microsoft Academic Search

The conductivity of (cosolvent + water) in the presence of increasing concentration of 1-hexadecylpyridinium bromide was measured at various temperatures. Acetonitrile, dimethylformamide, dimethylsulfoxide, dioxane and ethylene glycol were used as cosolvents. From the conductivity data, the critical micelle concentration c.m.c., and the effective degree of counter ion dissociation ?, were obtained at various temperatures. In all the cases studied, a

Naader Alizadeh

2000-01-01

351

First-Year Students' Expectations of Conduct and Consequence: A Case Study  

ERIC Educational Resources Information Center

|Research on first-year students' expectations about college has explored areas of academic and social expectations, but not first-year college students' expectations about judicial conduct and consequence. The purpose of this study was to empirically explore two questions: what are first year students' expectations about campus conduct and…

Crance Gutmann, Gina-Lyn

2008-01-01

352

Microwave Absorption Studies on Superparamagnetic Conducting Nanocomposites as Signal Coating Materials  

Microsoft Academic Search

In this paper, preparation and characterization of superparamagnetic nanoparticles and their polymer composites prepared by varing doping level of conducting polymer and their microwave absorption studies at radar system in 8–12 GHz frequency range have been discussed. These composites are conducting polymers have been widely used because of their lower density as well their good environmental stability as in the case

Mohammad Reza Saboktakin; Abel Maharramov; Mohammad Ali Ramazanov

2009-01-01

353

The adult antisocial syndrome with and without antecedent conduct disorder: Comparisons from an adoption study  

Microsoft Academic Search

DSM antisocial personality disorder (ASPD) requires a retrospective diagnosis of conduct disorder—historical behavior not present in everyone with adult ASPD criteria. Using adoption study data, we examined the impact of this requirement on biological and environmental risk associations. We also compared clinical correlates of adult antisocial behavior with and without prior conduct disorder. We defined three subgroups: DSM-III ASPD (n

Douglas R. Langbehn; Remi J. Cadoret

2001-01-01

354

Measurement of the electrical conductivity of metallic tubes by studying magnetic screening at low frequency  

NASA Astrophysics Data System (ADS)

We discuss a technique for measuring the electrical conductivity in metallic tubes based on Faraday's induction law. A detailed study of magnetic screening in the low frequency approximation leads to expressions that relate the screening coefficient to the geometry, magnetic permeability, and conductivity of the metallic tubes. We discuss experimental results for different tubes.

Íñiguez, J.; Raposo, V.; Flores, A. G.; Zazo, M.; Hernández-López, A.

2005-03-01

355

A study of VHF radio wave propagation over a water surface of variable conductivity  

Microsoft Academic Search

The ground wave propagation of VHF radio waves over an inhomogeneous sea surface of variable conductivity and under various sea roughness conditions is studied both theoretically and experimentally. Theoretical simulations predict a high sensitivity of the ground wave attenuation factor upon large variations of the surface conductivity, as can be found in an estuary. This sensitivity can be influenced appreciably

P. Forget; P. Broche

1991-01-01

356

Human subject protection; foreign clinical studies not conducted under an investigational new drug application. Final rule.  

PubMed

The Food and Drug Administration (FDA) is amending its regulations on acceptance of foreign clinical studies not conducted under an investigational new drug application (IND) (non-IND foreign clinical studies) as support for an IND or application for marketing approval for a drug or biological product. The final rule replaces the requirement that these studies be conducted in accordance with ethical principles stated in the Declaration of Helsinki (Declaration) issued by the World Medical Association (WMA), specifically the 1989 version (1989 Declaration), with a requirement that the studies be conducted in accordance with good clinical practice (GCP), including review and approval by an independent ethics committee (IEC). The final rule updates the standards for the acceptance of foreign clinical studies not conducted under an IND and helps ensure the protection of human subjects and the quality and integrity of data obtained from these studies. PMID:18567164

2008-04-28

357

Three ulnar nerve conduction studies in patients with ulnar neuropathy at the elbow  

Microsoft Academic Search

Objective: Ulnar neuropathy at the elbow is often difficult to localize by standard electrophysiologic testing. This study compared three ulnar nerve conduction studies to determine which was more sensitive in localizing ulnar neuropathy at the elbow.Methods: Motor studies to the first dorsal interosseous and the abductor digiti quinti and a mixed ulnar nerve sensory study across the elbow.Results: Motor studies

Milind J. Kothari; Michele Heistand; Seward B. Rutkove

1998-01-01

358

Status Update on the GPM Ground Validation Iowa Flood Studies (IFloodS) Field Experiment  

NASA Astrophysics Data System (ADS)

The overarching objective of integrated hydrologic ground validation activities supporting the Global Precipitation Measurement Mission (GPM) is to provide better understanding of the strengths and limitations of the satellite products, in the context of hydrologic applications. To this end, the GPM Ground Validation (GV) program is conducting the first of several hydrology-oriented field efforts: the Iowa Flood Studies (IFloodS) experiment. IFloodS will be conducted in the central to northeastern part of Iowa in Midwestern United States during the months of April-June, 2013. Specific science objectives and related goals for the IFloodS experiment can be summarized as follows: 1. Quantify the physical characteristics and space/time variability of rain (rates, DSD, process/"regime") and map to satellite rainfall retrieval uncertainty. 2. Assess satellite rainfall retrieval uncertainties at instantaneous to daily time scales and evaluate propagation/impact of uncertainty in flood-prediction. 3. Assess hydrologic predictive skill as a function of space/time scales, basin morphology, and land use/cover. 4. Discern the relative roles of rainfall quantities such as rate and accumulation as compared to other factors (e.g. transport of water in the drainage network) in flood genesis. 5. Refine approaches to "integrated hydrologic GV" concept based on IFloodS experiences and apply to future GPM Integrated GV field efforts. These objectives will be achieved via the deployment of the NASA NPOL S-band and D3R Ka/Ku-band dual-polarimetric radars, University of Iowa X-band dual-polarimetric radars, a large network of paired rain gauge platforms with attendant soil moisture and temperature probes, a large network of both 2D Video and Parsivel disdrometers, and USDA-ARS gauge and soil-moisture measurements (in collaboration with the NASA SMAP mission). The aforementioned measurements will be used to complement existing operational WSR-88D S-band polarimetric radar measurements, USGS streamflow, and Iowa Flood Center stream monitoring measurements. Coincident satellite datasets will be archived from current microwave imaging and sounding radiometers flying on NOAA, DMSP, NASA, and EU (METOP) low-earth orbiters, and rapid-scanned IR datasets collected from geostationary (GOES) platforms. Collectively the observational assets will provide a means to create high quality (time and space sampling) ground "reference" rainfall and stream flow datasets. The ground reference radar and rainfall datasets will provide a means to assess uncertainties in both satellite algorithms (physics) and products. Subsequently, the impact of uncertainties in the satellite products can be evaluated in coupled weather, land-surface and distributed hydrologic modeling frameworks as related to flood prediction.

Petersen, Walt; Krajewski, Witold

2013-04-01

359

Ballistic perforation of oxygen-free high conductivity copper and 7039 aluminum targets: A microstructural and hydrocode study  

NASA Astrophysics Data System (ADS)

This research involves an effort to study and compare the residual microstructures and dynamic behavior of two metallic targets of finite thicknesses, namely OFHC (oxygen-free high-conductivity) copper and 7039 aluminum, subjected to ballistic impact and perforation by a tungsten heavy alloy (WHA) projectile. Also included in this work is an attempt to validate mathematical modelling of experimental results through the use of a computer hydrocode, AUTODYN-2D, which allows for the simulation of ballistic penetration/perforation events and possible differentiation of fundamental mechanisms through validation strategies. These targets represent two very different FCC materials. The 7039 aluminum is extremely hard in contrast to a softer, ductile copper. The "failure" mechanisms appear to be different on a macroscopic scale, but may be similar on a microscopic scale. A preliminary investigation of the residual penetration channels in these two targets revealed significant microstructural differences. In the 7039 aluminum target there is a limited extent of microstructural deformation seen through optical microscopy, though numerous shear bands are observed near the channel wall and at the spalled region. Observations of the OHFC target, on the other hand, show a narrow region of recrystallized grains adjacent to the crater wall, beyond which is an extensive area of microband clusters. Similar features have been observed previously in connection with hypervelocity impact cratering in copper. This investigation will attempt to provide clues to the fundamental issues involved in the differing dynamic behavior of the two FCC materials. A detailed analysis of microstructures and their evolution will be conducted through metallography and transmission electron microscopy. Microhardness measurements will be performed to correlate the results of ballistic computer simulations through residual stress and hardness profiles. Computational modeling will be used to simulate the impact behavior of the two target materials and will be corroborated by experimental results to establish a validation of perforation geometry and residual stress mappings which can be related to actual residual hardness maps constructed experimentally. This study is an attempt to correlate microstructural issues with computer simulations and especially validation of these simulations to improve predictive models and general ballistic and hypervelocity perforation behavior in metal targets.

Kennedy, Christine

360

Study to Validate Prerequisites in Business Communication for Student Success  

Microsoft Academic Search

As business communication faculty members incorporate technology in their courses, curriculum designers need to address the extent to which students need to be computer literate. This study of undergraduate business administration students at California State University, Northridge, was undertaken to determine whether the business computer literacy requirement contributes to the students' overall performance in business communication. The findings indicate that

Susan Plutsky; Barbara Wilson

2000-01-01

361

Ecological validity of laboratory studies of videopoker gaming  

Microsoft Academic Search

This study compared the cognitive and behavioral components of videopoker players under laboratory and natural settings. Twenty regular gamblers (19 men and 1 woman) were matched into two groups on age and on frequency of gambling. Irrational verbalizations during gambling, monetary risk (number of bets doubled and number of tokens bet), and motivation served as dependent variables. Results showed no

Robert Ladouceur; Anne Gaboury; Annie Bujold; Nadine Lachance; Sarah Tremblay

1991-01-01

362

Facial Affect Scoring Technique: A First Validity Study.  

National Technical Information Service (NTIS)

The purpose of the study was to develop a tool for the measurement of facial behavior that would be equally applicable to predicting observers' judgments of emotion and to distinguishing emotional state as indicated by environmental condition or self-repo...

P. Ekman S. S. Tomkins W. V. Friesen

1971-01-01

363

Cognitive-Behavioral Models of Emotional Writing: A Validation Study  

Microsoft Academic Search

Previous research suggests that the Pennebaker writing paradigm may improve physical and psychological health; however, inconsistent findings suggest that it may not be suitable for community dissemination in its current format. This study manipulated writing instructions across groups in order to emphasise putative emotional processes. Three processes were isolated consistent with Cognitive-Behavioral models of trauma: exposure, devaluation, and benefit-finding. Essay

Adam J. Guastella; Mark R. Dadds

2006-01-01

364

A Validation Study of the Youth Development Assessment Device  

ERIC Educational Resources Information Center

|This article details the development of the Youth Development Assessment Device (YDAD), an instrument designed to measure a youth's experiences within youth development programs. A total of 1,074 adolescents, between 12 and 18 years of age, participated in the study. Exploratory factor analysis yielded three factors: Supportive Environment,…

Sabatelli, Ronald M.; Anderson, Stephen A.; Kosutic, Iva; Sanderson, Jessica; Rubinfeld, Stacey

2009-01-01

365

Virtual Environment Interpersonal Trust Scale: Validity and Reliability Study  

ERIC Educational Resources Information Center

|The purpose of this study is in the process of interpersonal communication in virtual environments is available from the trust problem is to develop a measurement tool. Trust in the process of distance education today, and has been a factor to be investigated. People, who take distance education course, they could may remain within the process…

Usta, Ertugrul

2012-01-01

366

An Analytical Study on a Model Describing Heat Conduction in Rectangular Radial Fin with Temperature-Dependent Thermal Conductivity  

NASA Astrophysics Data System (ADS)

The coupling of the homotopy perturbation method (HPM) and the variational iteration method (VIM) is a strong technique for solving higher dimensional initial boundary value problems. In this article, after a brief explanation of the mentioned method, the coupled techniques are applied to one-dimensional heat transfer in a rectangular radial fin with a temperature-dependent thermal conductivity to show the effectiveness and accuracy of the method in comparison with other methods. The graphical results show the best agreement of the three methods; however, the amount of calculations of each iteration for the combination of HPM and VIM was reduced markedly for multiple iterations. It was found that the variation of the dimensionless temperature strongly depends on the dimensionless small parameter {\\varepsilon_1}. Moreover, as the dimensionless length increases, the thermal conductivity of the fin decreases along the fin.

Hedayati, F.; Ganji, D. D.; Hamidi, S. M.; Malvandi, A.

2012-06-01

367

Validity and reliability of using photography for measuring knee range of motion: a methodological study  

Microsoft Academic Search

Background  The clinimetric properties of knee goniometry are essential to appreciate in light of its extensive use in the orthopaedic\\u000a and rehabilitative communities. Intra-observer reliability is thought to be satisfactory, but the validity and inter-rater\\u000a reliability of knee goniometry often demonstrate unacceptable levels of variation. This study tests the validity and reliability\\u000a of measuring knee range of motion using goniometry and

Justine M Naylor; Victoria Ko; Sam Adie; Clive Gaskin; Richard Walker; Ian A Harris; Rajat Mittal

2011-01-01

368

Lumbar segmental instability: a criterion-related validity study of manual therapy assessment  

Microsoft Academic Search

BACKGROUND: Musculoskeletal physiotherapists routinely assess lumbar segmental motion during the clinical examination of a patient with low back pain. The validity of manual assessment of segmental motion has not, however, been adequately investigated. METHODS: In this prospective, multi-centre, pragmatic, diagnostic validity study, 138 consecutive patients with recurrent or chronic low back pain (R\\/CLBP) were recruited. Physiotherapists with post-graduate training in

J Haxby Abbott; Brendan McCane; Peter Herbison; Graeme Moginie; Cathy Chapple; Tracy Hogarty

2005-01-01

369

Apples-to-apples in cross-validation studies: pitfalls in classifier performance measurement  

Microsoft Academic Search

Cross-validation is a mainstay for measuring performance and progress in machine learning. There are subtle differences in how exactly to compute accuracy, F-measure and Area Under the ROC Curve (AUC) in cross-validation studies. However, these details are not discussed in the literature, and incompatible methods are used by various papers and software packages. This leads to inconsistency across the research

George Forman; Martin Scholz

2010-01-01

370

MTLD, vocd-D, and HDD: A validation study of sophisticated approaches to lexical diversity assessment  

Microsoft Academic Search

The main purpose of this study was to examine the validity of the approach to lexical diversity assessment known as the measure\\u000a of textual lexical diversity (MTLD). The index for this approach is calculated as the mean length of word strings that maintain\\u000a a criterion level of lexical variation. To validate the MTLD approach, we compared it against the performances

Philip M. McCarthy; Scott Jarvis

2010-01-01

371

Technical tips: methods of warming and maintaining limb temperature during nerve conduction studies.  

PubMed

Many physiologic and nonphysiologic factors contribute to performing correct or incorrect nerve conduction studies. Nonphysiologic factors such as filter settings, averaging techniques, stimulus artifact, and supramaximal stimulation are just a few of the ones encountered during the nerve conduction study examination. Physiologic factors such as muscle atrophy, tremors and spasticity, edema, and profuse sweating are physical conditions that may pose technical problems during the study. Other general physiologic conditions such as height, aging and nerve maturation, variation between various nerve segments, and temperature may also contribute to the obtaining an accurate and correct nerve conduction study, as well as the electromyogram (EMG) itself. Obtaining and keeping the patient's surface temperature between 31 to 34 or 33 to 34 degrees Celsius, depending on which literature you read, is essential to obtaining and presenting correct nerve conduction studies. Cold limb temperature results in discrepancies in basic nerve conduction values such as amplitude, distal latency, conduction velocity, and duration in both motor and sensory studies. Cold to cool temperature also adversely affects the EMG. Repetitive stimulation studies for neuromuscular junction disease are greatly affected by decreasing the limb temperature. How to warm these patients and maintain a desirable temperature throughout the examination is vitally important. Methods of warming patients may vary from inexpensive to expensive in cost and simple to complex in nature. PMID:24046972

Morris, Jerry

2013-09-01

372

The "RG Sausage's" Missing Ingredients: Investigating the Validity of Reliability Generalization Study Design.  

ERIC Educational Resources Information Center

The purpose of this study was to examine the potential impact of selected methodological factors on the validity of conclusions from reliability generalization (RG) studies. The study focused on four factors; (1) missing data in the primary studies; (2) transformation of sample reliability estimates; (3) use of sample weights for estimating mean…

Romano, Jeanine; Kromrey, Jeffrey D.

373

Effect of surface deformations on contact conductance  

Microsoft Academic Search

This study experimentally investigates the influence of surface deformations on contact conductance when two dissimilar metals are brought into contact. Most relations between the contact conductance and the load use the surface hardness to characterize surface deformations. This inherently assumes that deformations are predominantly plastic. To check the validity of this assumption, five tests were conducted in the contact pressure

M. Williamson; A. Majumdar

1992-01-01

374

Reliability and validity of the tritrac-R3D accelerometer during backpacking: a case study.  

PubMed

This study investigated the utility of the Tritrac-R3D accelerometer as a reliable and valid instrument in the quantification of physical activity while backpacking in the field and to evaluate heart-rate responses and oxygen consumption to assess the feasibility of using the Tritrac-R3D to estimate caloric expenditure. Two 7-day backpacking expeditions were conducted in two consecutive years by a single subject at Grand Canyon National Park, Arizona. The average hiking heart rate ranged front 60% to 77% HRmax during the expeditions. The average rate of estimated caloric cost ranged from 6.8 to 11.7 kcals x min.(-1) (equivalent to 408 to 702 kcals x hr.(-1)), indicating a relatively moderate to high level of exertion. The Tritrac had adequate consistency and reliability in the field between the two expeditions in recorded activity counts. The Tritrac underestimated caloric expenditure during backpacking with changes in terrain, and hiking speed contributed to even greater disparity in accuracy. PMID:11693704

DeVoe, D; Dalleck, L

2001-08-01

375

Rorschach Measures of Aggression: A Laboratory-Based Validity Study  

Microsoft Academic Search

This study sought to complement the archival research designs that have established the empirical foundations of Rorschach aggression scores, including Exner's (2003) Aggressive Movement (AG) score and Meloy and Gacono's (1992) Aggressive Content (AgC), Aggressive Past (AgPast), and Aggressive Potential (AgPot) variables. Utilizing a highly controlled laboratory-based aggression paradigm and self-report measures of violence history in a sample of 35

Aaron J. Kivisto; Scott A. Swan

2012-01-01

376

A rapid screening tool for psychological distress in children 3-6years old: results of a validation study  

PubMed Central

Background The mental health needs of young children in humanitarian contexts often remain unaddressed. The lack of a validated, rapid and simple tool for screening combined with few mental health professionals able to accurately diagnose and provide appropriate care mean that young children remain without care. Here, we present the results of the principle cross-cultural validation of the “Psychological Screening for Young Children aged 3 to 6” (PSYCAa3-6). The PSYCa 3–6 is a simple scale for children 3 to 6 years old administered by non-specialists, to screen young children in crises and thereby refer them to care if needed. Methods This study was conducted in Maradi, Niger. The scale was translated into Hausa, using corroboration of independent translations. A cross-cultural validation was implemented using quantitative and qualitative methods. A random sample of 580 mothers or caregivers of children 3 to 6 years old were included. The tool was psychometrically examined and diagnostic properties were assessed comparing the PSYCa 3–6 against a clinical interview as the gold standard. Results The PSYCa 3–6 Hausa version demonstrated good concurrent validity, as scores correlated with the gold standard and the Clinical Global Impression Severity Scale (CGI-S) [rho?=?0.41, p-value?=?0.00]. A reduction procedure was used to reduce the scale from 40 to 22 items. The test-retest reliability of the PSYCa 3–6 was found to be high (ICC 0.81, CI95% [0.68; 0.89]). In our sample, although not the purpose of this study, approximately 54 of 580 children required subsequent follow-up with a psychologist. Conclusions To our knowledge, this is the first validation of a screening scale for children 3 to 6 years old with a cross-cultural validation component, for use in humanitarian contexts. The Hausa version of the PSYCa 3–6 is a reliable and a valuable screening tool for psychological distress. Further studies to replicate our findings and additional validations of the PSYCa 3–6 in other populations may help improve the delivery of mental health care to children.

2012-01-01

377

Validation of PON1 enzyme activity assays for longitudinal studies  

PubMed Central

Background Paraoxonase (PON1) enzymatic activity assays are used to characterize sensitivity to organophosphates and oxidative stress. Length of sample storage, temperature and other factors may influence variability of PON1 measurements, especially in longitudinal studies. Methods Effects of assay temperature, storage duration up to 7 y (?80°C), freeze-thaw cycles, the type of specimen (serum or heparinized plasma) and assay variability were evaluated for 4 PON1 substrate-specific assays using samples from two pediatric cohorts and laboratory volunteers. Results Intra- and inter- assay variation, as well as inter-laboratory variability for PON1 activities were <10%. The effect of storage duration up to 2 y was minimal. However, after 7 y, arylesterase, paraoxonase, and chlorpyrifos-oxonase activities decreased more noticeably. Similarly, while freeze-thaw cycles did not affect the PON1 activities in samples stored < 2 y, this factor was more significant after 7 y for arylesterase. Assay temperature and specimen type also influenced PON1 measurements. Conclusions Sources of technical variability of PON1 activity assays, including storage duration, freeze-thaw, and temperature should be monitored and minimized through study design, quality control procedures and statistical methods, especially in longitudinal studies where specimens may be stored for years prior to analysis.

Huen, Karen; Richter, Rebecca; Furlong, Clement; Eskenazi, Brenda; Holland, Nina

2009-01-01

378

Atrial fibrillation in the Malmö diet and cancer study: a study of occurrence, risk factors and diagnostic validity  

Microsoft Academic Search

The validity of atrial fibrillation (AF) diagnoses in national registers for use as endpoints in prospective studies has not\\u000a been evaluated. We studied the validity of AF diagnoses in Swedish national hospital discharge and cause of death registers\\u000a and the occurrence of and risk factors for AF in a middle-aged Swedish population using these registers. Our study included\\u000a the 30,447

J. Gustav Smith; Pyotr G. Platonov; Bo Hedblad; Gunnar Engström; Olle Melander

2010-01-01

379

Treatment Integrity: A Review of Intervention Studies Conducted with Children with Autism  

ERIC Educational Resources Information Center

|The purpose of this study was to assess the degree to which behavioral intervention studies conducted with children diagnosed with autism operationally defined the independent variables (IVs) and evaluated treatment integrity (TI). The study replicated the criteria from Gresham, Gansle, and Noell (1993) and focused exclusively on research studies

Wheeler, John J.; Baggett, Bob A.; Fox, James; Blevins, Leia

2006-01-01

380

Validating and updating a risk model for pneumonia - a case study  

PubMed Central

Background The development of risk prediction models is of increasing importance in medical research - their use in practice, however, is rare. Among other reasons this might be due to the fact that thorough validation is often lacking. This study focuses on two Bayesian approaches of how to validate a prediction rule for the diagnosis of pneumonia, and compares them with established validation methods. Methods Expert knowledge was used to derive a risk prediction model for pneumonia. Data on more than 600 patients presenting with cough and fever at a general practitioner’s practice in Switzerland were collected in order to validate the expert model and to examine the predictive performance of it. Additionally, four modifications of the original model including shrinkage of the regression coefficients, and two Bayesian approaches with the expert model used as prior mean and different weights for the prior covariance matrix were fitted. We quantify the predictive performance of the different methods with respect to calibration and discrimination, using cross-validation. Results The predictive performance of the unshrinked regression coefficients was poor when applied to the Swiss cohort. Shrinkage improved the results, but a Bayesian model formulation with unspecified weight of the informative prior lead to large AUC and small Brier score, naïve and after cross-validation. The advantage of this approach is the flexibility in case of a prior-data conflict. Conclusions Published risk prediction rules in clinical research need to be validated externally before they can be used in new settings. We propose to use a Bayesian model formulation with the original risk prediction rule as prior. The posterior means of the coefficients, given the validation data showed best predictive performance with respect to cross-validated calibration and discriminative ability.

2012-01-01

381

Simulation in laparoscopic surgery: a concurrent validity study for FLS  

Microsoft Academic Search

Background  Current assessments using the fundamentals of laparoscopic surgery (FLS) tasks are labour intensive and depend heavily on\\u000a expert raters. Hand motion analysis may offer an alternative method of objective evaluation of FLS performance.\\u000a \\u000a \\u000a \\u000a Purpose  The aim of this study was to assess whether a correlation exists between the expert rated assessments of the FLS tasks and\\u000a computer-based assessment of motion efficiency

George Xeroulis; Adam Dubrowski; Ken Leslie

2009-01-01

382

Study of dielectric relaxation and AC conductivity of InP:S single crystal  

NASA Astrophysics Data System (ADS)

The dielectric relaxation and AC conductivity of InP:S single crystal were studied in the frequency range from 100 to 5.25 × 105 Hz and in the temperature range from 296 to 455 K. The dependence of the dielectric constant (?1) and the dielectric loss (?2) on both frequency and temperature was investigated. Since no peak was observed on the dielectric loss, we used a method based on the electric modulus to evaluate the activation energy of the dielectric relaxation. Scaling of the electric modulus spectra showed that the charge transport dynamics is independent of temperature. The AC conductivity (?AC) was found to obey the power law: A?s. Analysis of the AC conductivity data and the frequency exponent showed that the correlated barrier hopping (CBH) model is the dominant mechanism for the AC conduction. The variation of AC conductivity with temperature at different frequencies showed that ?AC is a thermally activated process.

El-Nahass, M. M.; Ali, H. A. M.; El-Shazly, E. A.

2012-07-01

383

[Conduction disorders and sites of calcification of the mitral ring: 2-dimensional echocardiographic study].  

PubMed

The association between a calcified mitral annulus and impairment of cardiac impulse transmission is well known. However informations on the relations between the site of mitral calcification and conduction disturbance are still scanty. Twenty-nine patients (22 women and 7 men, mean age 64.4 +/- 13.1 years) with M-mode and two-dimensional echocardiographic evidence of mitral annulus calcifications were studied. The "annulus" was subdivided in 4 segments: antero-medial, antero-lateral, postero-medial and postero-lateral. Conduction disturbances were present in 15 patients (51.7%). Atrio-ventricular or intra-ventricular conduction defects were found in 12 out of 15 patients with calcifications of the antero-medial segment and only in 3 of 14 subjects without antero-medial calcifications (P less than .01). The presence of conduction defects therefore seems to be significantly increased when calcium deposition is located near the conduction system. PMID:3743933

Montemurro, D; Ronzani, G; Defilippi, G; Pizzuti, A; Brusca, A

1986-04-01

384

Validation study of the Colorado Learning Attitudes about Science Survey at a Hispanic-serving institution  

NASA Astrophysics Data System (ADS)

The Colorado Learning Attitudes about Science Survey (CLASS) has been widely acknowledged as a useful measure of student cognitive attitudes about science and learning. The initial University of Colorado validation study included only 20% non-Caucasian student populations. In this Brief Report we extend their validation to include a predominately under-represented minority population. We validated the CLASS instrument at Florida International University, a Hispanic-serving institution, by interviewing students in introductory physics classes using a semistructured protocol, examining students’ responses on the CLASS item statements, and comparing them to the items’ intended meaning. We find that in our predominately Hispanic population, 94% of the students’ interview responses indicate that the students interpret the CLASS items correctly, and thus the CLASS is a valid instrument. We also identify one potentially problematic item in the instrument which one third of the students interviewed consistently misinterpreted.

Sawtelle, Vashti; Brewe, Eric; Kramer, Laird

2009-12-01

385

Shock wave over hand muscles: a neurophysiological study on peripheral conduction nerves in normal subjects  

PubMed Central

Summary Background and purpose: shock waves are defined as a sequence of single sonic pulses largely used in the treatment of bone and tendon diseases and recently on muscular hypertonia in stroke patients. Our purpose is to investigate the short and long term effect of extra-corporeal shock wave therapy (ESWT) on the peripheral nerve conduction and central conductions from the treated muscles in normal human subjects in order to define safety criteria. Methods: we studied 10 patients normal subjects. Motor and sensory nerve conduction velocity and F response from right ipothenar eminence (abductor digiti minimi) of the hand was recorded. Furthermore MEP latency and amplitude and central conduction from the same muscles by transcranial magnetic stimulation was evaluated. In all subjects each neurophysiological measures were monitored before, immediately after, 15 minutes and after 30 minutes from the active ESWT treatment (1600 shots with an energy applied of 0.030 mj/mm2). Results: no significant short or long term changes were noted in sensory and motor peripheral nerve conduction and in central motor conduction in all the subjects evaluated after ESWT. Conclusions: the ESWT has no effect on sensory and motor peripheral nerve conduction and in central motor conduction. The ESWT using low level of energy represent a safety method for treating the muscles in human subjects without involvement of motor or sensory nervous trunks. Different mechanisms of action of ESWT are discussed.

Manganotti, Paolo; Amelio, Ernesto; Guerra, Claudio

2012-01-01

386

Significance of Childhood Conduct Problems to Later Development of Conduct Disorder Among Children With ADHD: A Prospective Follow-Up Study  

Microsoft Academic Search

This study investigates whether low to moderate levels of childhood oppositional defiant disorder (ODD) and conduct disorder (CD) behaviors contribute to the development of clinically diagnosed CD in adolescence, in children with attention deficit hyperactivity disorder (ADHD). Participants were 207 White boys (ages 6–12) with ADHD free of conduct disorder diagnoses. Parent and teacher ratings were obtained. Participants were assessed

Salvatore Mannuzza; Rachel G. Klein; Howard Abikoff; John L. Moulton III

2004-01-01

387

A study on validity of cortical alpha connectivity for schizophrenia.  

PubMed

Abnormalities in schizophrenia are thought to be associated with functional disconnections between different brain regions. Most previous studies on schizophrenia have considered high-band connectivity in preference to the Alpha band, as there has been some uncertainty correlating the latter to the condition. In this paper we attempt to clarify this correlation using an Electroencephalogram (EEG) analysis of the Alpha band from schizophrenic patients. Global, regional Omega and dimensional complexity and local Omega complexity differentials (LCD) of single channel are calculated using 16 channels of resting EEG data from 31 adult patients with schizophrenia and 31 age/sex matched control subjects. It was found that, compared to the controls, anterior alpha Omega and dimensional complexity are higher in schizophrenia patients (p<0.05) with the single channel LCD also increasing at FP1, FP2, F7 and F8 electrodes. Furthermore, higher left hemisphere dimensional complexity and LCD at T3 point was also found. The results suggest there is lower connectivity in the pre-frontal and left temporal regions with respect to the alpha band in schizophrenia patients. PMID:24110430

Peng, Hong; Hu, Bin; Li, Lanlan; Ratcliffe, Martyn; Zhai, Jingwei; Zhao, Qinglin; Shi, Qiuxia; Li, Yunpeng; Liu, Quanying

2013-07-01

388

Validation of self-reported anthropometrics in the Adventist Health Study 2  

Microsoft Academic Search

Background  Relying on self-reported anthropometric data is often the only feasible way of studying large populations. In this context,\\u000a there are no studies assessing the validity of anthropometrics in a mostly vegetarian population. The objective of this study\\u000a was to evaluate the validity of self-reported anthropometrics in the Adventist Health Study 2 (AHS-2).\\u000a \\u000a \\u000a \\u000a \\u000a Methods  We selected a representative sample of 911 participants

Maira Bes-Rastrollo; Joan Sabaté; Karen Jaceldo-Siegl; Gary E Fraser

2011-01-01

389

Validity and Feasibility of a Digital Diet Estimation Method for Use with Preschool Children: A Pilot Study  

ERIC Educational Resources Information Center

|Objective: The goal of the study was to assess the validity and feasibility of a digital diet estimation method for use with preschool children in "Head Start." Methods: Preschool children and their caregivers participated in validation (n = 22) and feasibility (n = 24) pilot studies. Validity was determined in the metabolic research unit using…

Nicklas, Theresa A.; O'Neil, Carol E.; Stuff, Janice; Goodell, Lora Suzanne; Liu, Yan; Martin, Corby K.

2012-01-01

390

Validity and reliability tests in case study research: a literature review with “hands-on” applications for each research phase  

Microsoft Academic Search

Despite the advantages of the case study method, its reliability and validity remain in doubt. Tests to establish the validity and reliability of qualitative data are important to determine the stability and quality of the data obtained. However, there is no single, coherent set of validity and reliability tests for each research phase in case study research available in the

Andreas M. Riege

2003-01-01

391

The reliability and validity of the learning and study strategies inventory (LASSI) with college developmental students  

Microsoft Academic Search

This study compared the reliability and validity of the ten subtests of the Learning and Study Strategies Inventory (LASSI) (Weinstein et al., 1987) obtained from 99 college developmental studies students enrolled in an introductory reading course in a southeastern, urban, two?year community college with the norming values obtained by Weinstein, Schulte, and Palmer (1987). The results indicated that nine of

Mary P. Deming; Lynda S. Idleman

1994-01-01

392

An Assessment of Treatment Integrity in Behavioral Intervention Studies Conducted with Persons with Mental Retardation  

ERIC Educational Resources Information Center

|The purpose of this study was to assess the degree to which behavioral intervention studies conducted with persons with mental retardation operationally defined the independent variables and evaluated and reported measures of treatment integrity. The study expands the previous work in this area reported by Gresham, Gansle, and Noell (1993) and…

Wheeler, John J.; Mayton, Michael R.; Carter, Stacy L.; Chitiyo, Morgan; Menendez, Anthony L.; Huang, Ann

2009-01-01

393

Kindergarten Teachers' Perspectives on Developmentally Appropriate Practices (DAP): A Study Conducted in Mumbai (India)  

ERIC Educational Resources Information Center

|A qualitative study examining teachers' beliefs regarding developmentally appropriate practices was conducted in the city of Mumbai, India. Twelve kindergarten teacher's were interviewed for this study, and a constant comparative method was used to analyze the interviews. Six themes were identified within this study. The themes highlighted…

Hegde, Archana V.; Cassidy, Deborah J.

2009-01-01

394

Kindergarten Teachers' Perspectives on Developmentally Appropriate Practices (DAP): A Study Conducted in Mumbai (India)  

Microsoft Academic Search

A qualitative study examining teachers' beliefs regarding developmentally appropriate practices was conducted in the city of Mumbai, India. Twelve kindergarten teachers were interviewed for this study, and a constant comparative method was used to analyze the interviews. Six themes were identified within this study. The themes highlighted distinct differences between American and Indian cultures, as well as striking similarities, and

Archana V. Hegde; Deborah J. Cassidy

2009-01-01

395

The conductive path in HfO2: first principles study  

NASA Astrophysics Data System (ADS)

The conductive path formed by the interstitial Ag or substitutional Ag in HfO2 was investigated by using the Vienna ab initio simulation package based on the DFT theory. The calculated results indicated that the ordering of interstitial Ag ions at special positions can form a conductive path, and it cannot form at other positions. The orientation dependence of this conductive path was then investigated. Various types of super cells are also built to study the rupture of the path, which corresponds to some possible “off" states.

Maoxiu, Zhou; Qiang, Zhao; Wei, Zhang; Qi, Liu; Yuehua, Dai

2012-07-01

396

A numerical study of performance of a slider bearing with heat conduction to the pad  

Microsoft Academic Search

A numerical study of thermohydrodynamic performance of a high-speed slider bearing with conduction to a stationary pad has been analyzed. The partial differential equations governing the fluid-film mass, momentum and energy conservations coupled with the heat conduction equation for the solid stationary pad assuming temperature-dependent density and viscosity, are solved using streamline upwind Petrov–Galerkin finite element method to yield various

B. V. Rathish Kumar; P. Srinivasa Rao; Prawal Sinha

2001-01-01

397

A study of contact resistance of conductive adhesives based on anhydride-cured epoxy systems  

Microsoft Academic Search

Electrically conductive adhesives (ECAs) are an environmentally friendly alternative to tin\\/lead (Sn\\/Pb) solders in electronics packaging applications. However, current conductive technology is still in its infancy and limitations do exist. One of the critical reliability issues is that contact resistance of silver flake-filled ECAs on nonnoble metals increases in elevated temperature and humidity environments. The main objective of this study

Daoqiang Lu; C. P. Wong

2000-01-01

398

Feasibility, reliability, and validity of the EQ-5D-Y: results from a multinational study  

PubMed Central

Purpose To examine the feasibility, reliability, and validity of the newly developed EQ-5D-Y. Methods The EQ-5D-Y was administered in population samples of children and adolescents in Germany, Italy, South Africa, Spain, and Sweden. Percentages of missing values and reported problems were calculated. Test–retest reliability was determined. Spearman’s rank correlation coefficients with other generic measures of HRQOL were calculated. Known groups’ validity was examined by comparing groups with a priori expected differences in HRQOL. Results Between 91 and 100% of the respondents provided valid scorings. Sweden had the lowest proportion of reported problems (1–24.9% across EQ-5D-Y dimensions), with the highest proportions in South Africa (2.8–47.3%) and Italy (4.3–39.0%). Percentages of agreement in test–retest reliability ranged between 69.8 and 99.7% in the EQ-5D-Y dimensions; Kappa coefficients were up to 0.67. Correlation coefficients with other measures of self-rated health indicated convergent validity (up to r = ?0.56). Differences between groups classified according to presence of chronic conditions, self-rated overall health and psychological problems provided preliminary evidence of known groups’ validity. Conclusions Results provide preliminary evidence of the instrument’s feasibility, reliability and validity. Further study is required in clinical samples and for possible future applications in economic analyses.

Wille, Nora; Badia, Xavier; Bonsel, Gouke; Burstrom, Kristina; Cavrini, Gulia; Devlin, Nancy; Egmar, Ann-Charlotte; Gusi, Narcis; Herdman, Michael; Jelsma, Jennifer; Kind, Paul; Olivares, Pedro R.; Scalone, Luciana; Greiner, Wolfgang

2010-01-01

399

Molecular dynamics studies of material property effects on thermal boundary conductance.  

PubMed

Thermal boundary resistance (inverse of conductance) between different material layers can dominate the overall thermal resistance in nanostructures and therefore impact the performance of the thermal property limiting nano devices. Because relationships between material properties and thermal boundary conductance have not been fully understood, optimum devices cannot be developed through a rational selection of materials. Here we develop generic interatomic potentials to enable material properties to be continuously varied in extremely large molecular dynamics simulations to explore the dependence of thermal boundary conductance on the characteristic properties of materials such as atomic mass, stiffness, and interfacial crystallography. To ensure that our study is not biased to a particular model, we employ different types of interatomic potentials. In particular, both a Stillinger-Weber potential and a hybrid embedded-atom-method + Stillinger-Weber potential are used to study metal-on-semiconductor compound interfaces, and the results are analyzed considering previous work based upon a Lennard-Jones (LJ) potential. These studies, therefore, reliably provide new understanding of interfacial transport phenomena particularly in terms of effects of material properties on thermal boundary conductance. Our most important finding is that thermal boundary conductance increases with the overlap of the vibrational spectra between metal modes and the acoustic modes of the semiconductor compound, and increasing the metal stiffness causes a continuous shift of the metal modes. As a result, the maximum thermal boundary conductance occurs at an intermediate metal stiffness (best matched to the semiconductor stiffness) that maximizes the overlap of the vibrational modes. PMID:23715116

Zhou, X W; Jones, R E; Duda, J C; Hopkins, P E

2013-05-29

400

Assessment of English language development: a validity study of a district initiative.  

PubMed

The San Francisco Unified School District (SFUSD) uses the Language and Literacy Assessment Rubric (LALAR) as the secondary measurement required by the No Child Left Behind (NCLB) Act to measure English proficiency of English language learners (ELLs). In this analysis, the Rasch model is used to identify whether the LALAR is a valid measurement instrument and scale to measure the "English proficiency" of ELLs. This analysis investigates the relationship between student ability () and the probability that the student will respond correctly to an item on the LALAR. Controlling for this relationship, the item characteristics of each item, ability of each student, and measurement error associated with each score were mathematically derived. This will allow for validity and reliability tests to be conducted, which will help determine if the LALAR is a useful accountability measure for ELLs. PMID:22089508

Sanchez, Juan D

2011-01-01

401

The Hospital Anxiety and Depression Scale (HADS): translation and validation study of the Iranian version  

PubMed Central

Background The Hospital Anxiety and Depression Scale (HADS) is a widely used instrument to measure psychological morbidity in cancer patients. This study aimed to translate and test the reliability and validity of the Iranian version of the HADS. Methods The English language version of the HADS was translated into Persian (Iranian language) and was used in this study. The questionnaire was administered to a consecutive sample of 167 breast cancer patients and statistical analysis was performed to test the reliability and validity of the HADS. Results In general the Iranian version of the HADS was found to be acceptable to almost all patients (99%). Cronbach's alpha coefficient (to test reliability) has been found to be 0.78 for the HADS anxiety sub-scale and 0.86 for the HADS depression sub-scale. Validity as performed using known groups comparison analysis showed satisfactory results. Both anxiety and depression sub-scales discriminated well between sub-groups of patients differing in clinical status as defined by their disease stage. Conclusion This preliminary validation study of the Iranian version of the HADS proved that it is an acceptable, a reliable and valid measure of psychological distress among cancer patients.

Montazeri, Ali; Vahdaninia, Mariam; Ebrahimi, Mandana; Jarvandi, Soghra

2003-01-01

402

Using virtual reality to evaluate executive functioning among persons with schizophrenia: a validity study.  

PubMed

Persons with Schizophrenia experience difficulties with Executive Functioning (EF) that affect independence and participation in activities. Specifically, EF impacts performance in Instrumental Activities of Daily Living (IADL) that require flexible thinking and accommodation to complex environments. However, less is known how schizophrenia affects EF and individuals' performance in activities. IADL performance can be tested using a virtual reality (VR) environment that simulates real life activities. The purpose of this study was: 1) to examine the feasibility and validity of the Virtual Action Planning-Supermarket (VAP-S) to assess EF in persons with schizophrenia as compared to a standardized EF measure (the Behavioral Assessment of Dysexecutive Syndrome, BADS); 2) to compare performance of persons with schizophrenia and healthy controls in the VAP-S; 3) to assess the ability of the VAP-S to differentiate between different levels of EF within schizophrenia; 4) to explore the relationships between negative and positive symptoms and performance on the tests. Thirty persons with schizophrenia were matched with 30 healthy controls. Significant differences in performance between research and control groups were detected on the VAP-S and BADS, with the research group performing worse. Large variations in number of purchases within the VAP-S by the research group point to level of task completion thus secondary analysis was conducted. There was a significant negative correlation between level of the negative signs and overall performance on the BADS and on most measures of the VAP-S. Results of this study support the use the VAP-S to assess EF among persons with Schizophrenia. PMID:19850451

Josman, Naomi; Schenirderman, Anat Elbaz; Klinger, Evelyne; Shevil, Eynat

2009-10-22

403

The Edinburgh Postnatal Depression Scale (EPDS): translation and validation study of the Iranian version  

Microsoft Academic Search

BACKGROUND: The Edinburgh Postnatal Depression Scale (EPDS) is a widely used instrument to measure postnatal depression. This study aimed to translate and to test the reliability and validity of the EPDS in Iran. METHODS: The English language version of the EPDS was translated into Persian (Iranian language) and was used in this study. The questionnaire was administered to a consecutive

Ali Montazeri; Behnaz Torkan; Sepideh Omidvari

2007-01-01

404

How valid and reliable are patient satisfaction data? An analysis of 195 studies  

Microsoft Academic Search

Objective. To assess the properties of validity and reliability of instruments used to assess satisfaction in a broad sample of health service user satisfaction studies, and to assess the level of awareness of these issues among study authors. Design. Examination and analysis of 195 papers published in 1994 in 139 journals. The following databases were searched: British Nursing Index, CINAHL,

JOHN SITZIA

1999-01-01

405

The Gifted Rating Scales-School Form: A Validation Study Based on Age, Gender, and Race  

ERIC Educational Resources Information Center

|This study examined the internal consistency and validity of a new rating scale to identify gifted students, the Gifted Rating Scales-School Form (GRS-S). The study explored the effect of gender, race/ethnicity, age, and rater familiarity on GRS-S ratings. One hundred twenty-two students in first to eighth grade from elementary and middle schools…

Pfeiffer, Steven; Petscher, Yaacov; Kumtepe, Alper

2008-01-01

406

Compassion Fatigue and Psychological Distress Among Social Workers: A Validation Study  

Microsoft Academic Search

Few studies have focused on caring professionals and their emotional exhaustion from working with traumatized clients, referred to as compassion fatigue (CF). The present study had 2 goals: (a) to assess the psychometric properties of a CF scale, and (b) to examine the scale's predictive validity in a multivariate model. The data came from a survey of social workers living

Richard E. Adams; Joseph A. Boscarino; Charles R. Figley

2006-01-01

407

Validation Study on Five Cytotoxicity Assays by JSAAE III. Quality of Collected Data Files  

Microsoft Academic Search

In the inter-laboratory validation study organized by JSAAE to evaluate the practicability of five cytotoxicity assays as feasible alternatives to the Draize eye irritation test, we have carried out thorough data cleaning before data analysis in order to be assured of the reliability and correctness of the results of the study, since so many errors on protocol understanding and data

Takashi Omori; Kaoru Saijo; Mayako Kato; Hiroshi Itagaki; Makoto Hayashi; Satoru Miyazaki; Tadao Ohno; Hidiaki Sugawara; Noriko Teramoto; Noriho Tanaka; Shinobu Wakuri; Isao Yoshimura

408

Conductance of ferro- and antiferro-magnetic single-atom contacts: A first-principles study  

NASA Astrophysics Data System (ADS)

We present a first-principles study on the spin dependent conductance of five single-atom magnetic junctions consisting of a magnetic tip and an adatom adsorbed on a magnetic surface, i.e., the Co-Co/Co(001) and Ni-X/Ni(001) (X = Fe, Co, Ni, Cu) junctions. When their spin configuration changes from ferromagnetism to anti-ferromagnetism, the spin-up conductance increases while the spin-down one decreases. For the junctions with a magnetic adatom, there is nearly no spin valve effect as the decreased spin-down conductance counteracts the increased spin-up one. For the junction with a nonmagnetic adatom (Ni-Cu/Ni(001)), a spin valve effect is obtained with a variation of 22% in the total conductance. In addition, the change in spin configuration enhances the spin filter effect for the Ni-Fe/Ni(001) junction but suppresses it for the other junctions.

Tan, Zhi-Yun; Zheng, Xiao-long; Ye, Xiang; Xie, Yi-qun; Ke, San-Huang

2013-08-01

409

Thermal conductivity studies of metal dispersed multiwalled carbon nanotubes in water and ethylene glycol based nanofluids  

SciTech Connect

High thermal conducting metal nanoparticles have been dispersed on the multiwalled carbon nanotubes (MWNTs) outer surface. Structural and morphological characterizations of metal dispersed MWNTs have been carried out using x-ray diffraction analysis, high resolution transmission electron microscopy, energy dispersive x-ray analysis, and Fourier transform infrared spectroscopy. Nanofluids have been synthesized using metal-MWNTs in de-ionized water (DI water) and ethylene glycol (EG) base fluids. It has been observed that nanofluids maintain the same sequence of thermal conductivity as that of metal nanoparticles Ag-MWNTs>Au-MWNTs>Pd-MWNTs. A maximum enhancement of 37.3% and 11.3% in thermal conductivity has been obtained in Ag-MWNTs nanofluid with DI water and EG as base fluids, respectively, at a volume fraction of 0.03%. Temperature dependence study also shows enhancement of thermal conductivity with temperature.

Jha, Neetu; Ramaprabhu, S. [Department of Physics, Alternative Energy and Nanotechnology Laboratory (AENL), Nano Functional Materials Technology Centre (NFMTC), Indian Institute of Technology Madras, Chennai 600036 (India)

2009-10-15

410

AC Conductivity Studies in Lithium-Borate Glass Containing Gold Nanoparticles  

NASA Astrophysics Data System (ADS)

Gold nanoparticles have been synthesized in a base glass with composition 30Li2O-70B2O3 using gold chloride (HAuCl4.3H2O) as a dopant. The samples are characterized using XRD, ESR, SEM and optical absorption in the visible range. AC conductivity studies have been performed at RT over a frequency range 100 to 10 MHz. The dc conductivity is calculated from the complex impedence plot. The dc conductivity is found to be increasing with the increase of dopant concentration. AC conductivity data is fitted with Almond-West law with power exponent `s'. The values of `s' is found to lie in the range of 0.70-0.73.

Shivaprakash, Y.; Anavekar, R. V.

2011-07-01

411

Methodological, Theoretical, Infrastructural, and Design Issues in Conducting Good Outcome Studies  

ERIC Educational Resources Information Center

|This article outlines a set of methodological, theoretical, and other issues relating to the conduct of good outcome studies. The article begins by considering the contribution of evidence-based medicine to the methodology of outcome research. The lessons which can be applied in outcome studies in nonmedical settings are described. The article…

Kelly, Michael P.; Moore, Tessa A.

2011-01-01

412

GUIDE TO CONDUCTING TREATABILITY STUDIES UNDER CERCLA: SOIL WASHING - INTERIM GUIDANCE  

EPA Science Inventory

Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (RI/FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation, and Liab...

413

The effects of iodine on intelligence in children: a meta- analysis of studies conducted in China  

Microsoft Academic Search

This study quantifies the effects of iodine on the intellectual development of children using a systematic manual literature search of Chinese publications related to iodine deficiency disorders. The Chinese Medical Reference Database, Medline, and Cochrane library were searched electronically in Chinese and English. Inclusion criteria included: studies conducted in China, comparing children (<16 ys) living in naturally iodine sufficient (IS)

Ming Qian; Dong Wang; Val Gebski MSTAT; Yu Qin Yan; Mu Li; Pei Chen

414

Study of the Kinetics of an S[subscript N]1 Reaction by Conductivity Measurement  

ERIC Educational Resources Information Center

|Substitution reactions, a central part of organic chemistry, provide a model system in physical chemistry to study reaction rates and mechanisms. Here, the use of inexpensive and readily available commercial conductivity probes coupled with computer data acquisition for the study of the temperature and solvent dependence of the solvolysis of…

Marzluff, Elaine M.; Crawford, Mary A.; Reynolds, Helen

2011-01-01

415

ORGANOTIN TOXICITY STUDIES CONDUCTED WITH SELECTED MARINE ORGANISMS AT EPA'S ENVIRONMENTAL RESEARCH LABORATORY, GULF BREEZE, FLORIDA  

EPA Science Inventory

Studies on effect of bis(tri-n-butyltin)oxide (TBTO) and other organotins on marine species have been conducted at the U.S. Environmental Protection Agency's laboratory at Gulf Breeze, Florida, since 1983. First studies were done on two species of algae, Skeletonema costatum and ...

416

A summary report of the COLIPA international validation study on alternatives to the draize rabbit eye irritation test  

Microsoft Academic Search

The principal goal of this study was to determine whether the results from a set of selected currently available alternative methods as used by cosmetics companies are valid for predicting the eye irritation potential of cosmetics formulations and ingredients and, as a consequence, could be valid replacements for the Draize eye irritation test. For the first time in a validation

P. G. Brantom; L. H. Bruner; M. Chamberlain; O. De Silva; J. Dupuis; L. K. Earl; D. P. Lovell; W. J. W. Pape; M. Uttley; D. M. Bagley; F. W. Baker; M. Bracher; P. Courtellemont; L. Declercq; S. Freeman; W. Steiling; A. P. Walker; G. J. Carr; N. Dami; G. Thomas; J. Harbell; P. A. Jones; U. Pfannenbecker; J. A. Southee; M. Tcheng; H. Argembeaux; D. Castelli; R. Clothier; D. J. Esdaile; H. Itigaki; K. Jung; Y. Kasai; H. Kojima; U. Kristen; M. Larnicol; R. W. Lewis; K. Marenus; O. Moreno; A. Peterson; E. S. Rasmussen; C. Robles; M. Stern

1997-01-01

417

Internal and external validation of predictive models: A simulation study of bias and precision in small samples  

Microsoft Academic Search

We performed a simulation study to investigate the accuracy of bootstrap estimates of optimism (internal validation) and the precision of performance estimates in independent validation samples (external validation). We combined two data sets containing children presenting with fever without source (n=376+179=555; 120 bacterial infections). Random samples were drawn from this combined data set for the development (n=376) and validation (n=179)

Ewout W Steyerberg; Sacha E Bleeker; Henriëtte A Moll; Diederick E Grobbee; Karel G. M Moons

2003-01-01

418

Study of lattice thermal conductivity of alpha-zirconium by molecular dynamics simulation  

NASA Astrophysics Data System (ADS)

The non-equilibrium molecular dynamics method is adapted to calculate the phonon thermal conductivity of alpha-zirconium. By exchanging velocities of atoms in different regions, the stable heat flux and the temperature gradient are established to calculate the thermal conductivity. The phonon thermal conductivities under different conditions, such as different heat exchange frequencies, different temperatures, different crystallographic orientations, and crossing grain boundary (GB), are studied in detail with considering the finite size effect. It turns out that the phonon thermal conductivity decreases with the increase of temperature, and displays anisotropies along different crystallographic orientations. The phonon thermal conductivity in [0001] direction (close-packed plane) is largest, while the values in other two directions of [21¯1¯0] and [011¯0] are relatively close. In the region near GB, there is a sharp temperature drop, and the phonon thermal conductivity is about one-tenth of that of the single crystal at 550 K, suggesting that the GB may act as a thermal barrier in the crystal.

Wu, Tian-Yu; Lai, Wen-Sheng; Fu, Bao-Qin

2013-07-01

419

Development of a high pressure electrical conductivity probe for experimental studies of gas hydrates in electrolytes  

NASA Astrophysics Data System (ADS)

We previously reported the development of a high pressure automated lag time apparatus and a high pressure video cell for experimental study of nucleation and growth of gas hydrates. Here we report the development of a high pressure electrical conductivity probe that monitors the electrical conductivity of an electrolyte that is subjected to a linear cooling ramp at elevated hydrate-forming-gas pressures. The electrical conductivity steadily decreases as the linear cooling progresses because of the increasing viscosity of the electrolyte and the consequently decreasing mobility of the ions. The onset of the formation of methane-propane mixed gas hydrate films at the gas-electrolyte interface is marked by an upward spike in the electrical conductivity. The physical mechanisms behind this phenomenon remain to be elucidated. Continued cooling of the electrolyte to, and subsequent holding of, the temperature at 273 K eventually results in decreased electrical conductivity. This conductivity signal can be used for the detection of the onset of the formation of gas hydrates in optically opaque samples that contain electrolytes.

Maeda, Nobuo

2013-01-01

420

Development of a high pressure electrical conductivity probe for experimental studies of gas hydrates in electrolytes.  

PubMed

We previously reported the development of a high pressure automated lag time apparatus and a high pressure video cell for experimental study of nucleation and growth of gas hydrates. Here we report the development of a high pressure electrical conductivity probe that monitors the electrical conductivity of an electrolyte that is subjected to a linear cooling ramp at elevated hydrate-forming-gas pressures. The electrical conductivity steadily decreases as the linear cooling progresses because of the increasing viscosity of the electrolyte and the consequently decreasing mobility of the ions. The onset of the formation of methane-propane mixed gas hydrate films at the gas-electrolyte interface is marked by an upward spike in the electrical conductivity. The physical mechanisms behind this phenomenon remain to be elucidated. Continued cooling of the electrolyte to, and subsequent holding of, the temperature at 273 K eventually results in decreased electrical conductivity. This conductivity signal can be used for the detection of the onset of the formation of gas hydrates in optically opaque samples that contain electrolytes. PMID:23387698

Maeda, Nobuo

2013-01-01

421

Efficient regression calibration for logistic regression in main study/internal validation study designs with an imperfect reference instrument.  

PubMed

An extension to the version of the regression calibration estimator proposed by Rosner et al. for logistic and other generalized linear regression models is given for main study/internal validation study designs. This estimator combines the information about the parameter of interest contained in the internal validation study with Rosner et al.'s regression calibration estimate, using a generalized inverse-variance weighted average. It is shown that the validation study selection model can be ignored as long as this model is jointly independent of the outcome and the incompletely observed covariates, conditional, at most, upon the surrogates and other completely observed covariates. In an extensive simulation study designed to follow a complex, multivariate setting in nutritional epidemiology, it is shown that with validation study sizes of 340 or more, this estimator appears to be asymptotically optimal in the sense that it is nearly unbiased and nearly as efficient as a properly specified maximum likelihood estimator. A modification to the regression calibration variance estimator which replaces the standard uncorrected logistic regression coefficient variance with the sandwich estimator to account for the possible misspecification of the logistic regression fit to the surrogate covariates in the main study, was also studied in this same simulation experiment. In this study, the alternative variance formula yielded results virtually identical to the original formula. A version of the proposed estimator is also derived for the case where the reference instrument, available only in the validation study, is imperfect but unbiased at the individual level and contains error that is uncorrelated with other covariates and with error in the surrogate instrument. Replicate measures are obtained in a subset of study participants. In this case it is shown that the validation study selection model can be ignored when sampling into the validation study depends, at most, only upon perfectly measured covariates. Two data sets, a study of fever in relation to occupational exposure to antineoplastics among hospital pharmacists and a study of breast cancer incidence in relation to dietary intakes of alcohol and vitamin A, adjusted for total energy intake, from the Nurses' Health Study, were analysed using these new methods. In these data, because the validation studies contained less than 200 observations and the events of interest were relatively rare, as is typical, the potential improvements offered by this new estimator were not apparent. PMID:11135353

Spiegelman, D; Carroll, R J; Kipnis, V

2001-01-15

422

The effects of an unexpected spider stimulus on skin conductance responses and eye movements: an inattentional blindness study.  

PubMed

Are spiders evolutionarily relevant threat cues that capture attention automatically and preattentively-also in non-fearful persons? Previous studies concerning this question did not examine responses to unexpected spider stimuli, although this is an ecologically valid situation. Therefore, we conducted an inattentional blindness (IB) experiment. While unselected participants (N = 120) were focusing their attention on a visual discrimination task, suddenly a spider or a flower image appeared. The rates of reported detection were not enhanced for spider images, and fear of spiders had no moderating influence on IB rates. However, spider pictures in general elicited greater skin conductance responses than flower pictures, and this difference was also observed for pictures that were not reported afterward. Moreover, eye movement data revealed that the spider stimulus was initially fixated more often than the flower stimulus. In sum, our findings imply that enhanced reactions to unexpected spider images are independent of fear level and include early engagement processes. Awareness of a spider picture does not seem to be a prerequisite for elevated arousal. PMID:22227916

Wiemer, Julian; Gerdes, Antje B M; Pauli, Paul

2012-01-07

423

A Platform for the Remote Conduct of Gene-Environment Interaction Studies  

PubMed Central

Background Gene-environment interaction studies offer the prospect of robust causal inference through both gene identification and instrumental variable approaches. As such they are a major and much needed development. However, conducting these studies using traditional methods, which require direct participant contact, is resource intensive. The ability to conduct gene-environment interaction studies remotely would reduce costs and increase capacity. Aim To develop a platform for the remote conduct of gene-environment interaction studies. Methods A random sample of 15,000 men and women aged 50+ years and living in Cardiff, South Wales, of whom 6,012 were estimated to have internet connectivity, were mailed inviting them to visit a web-site to join a study of successful ageing. Online consent was obtained for questionnaire completion, cognitive testing, re-contact, record linkage and genotyping. Cognitive testing was conducted using the Cardiff Cognitive Battery. Bio-sampling was randomised to blood spot, buccal cell or no request. Results A heterogeneous sample of 663 (4.5% of mailed sample and 11% of internet connected sample) men and women (47% female) aged 50–87 years (median?=?61 yrs) from diverse backgrounds (representing the full range of deprivation scores) was recruited. Bio-samples were donated by 70% of those agreeing to do so. Self report questionnaires and cognitive tests showed comparable distributions to those collected using face-to-face methods. Record linkage was achieved for 99.9% of participants. Conclusion This study has demonstrated that remote methods are suitable for the conduct of gene-environment interaction studies. Up-scaling these methods provides the opportunity to increase capacity for large-scale gene-environment interaction studies.

Gallacher, John; Collins, Rory; Elliott, Paul; Palmer, Stephen; Burton, Paul; Mitchell, Clive; John, Gareth; Lyons, Ronan

2013-01-01

424

A study on the validity of the point-particle model for particle-turbulence interaction  

NASA Astrophysics Data System (ADS)

The point-particle model, widely used in simulations of particle-turbulence interaction, is justified when the particle size is smaller than or comparable to the Kolmogorov scale. The precise limits of validity of the approximation and the manner in which errors accrue when the particle size increases are not well known. In the present work, direct simulations are conducted for a single finite-size particle suspended in a decaying homogeneous turbulent flow generated with a spectral code as an intial condition. The simulations are conducted by means of the PHYSALIS method. The trajectories of finite-size and point particles are compared as the particle radius is increased above the Kolmogorov scale for different Stokes numbers.

Zhang, Zhongzhen; Prosperetti, Andrea

2002-11-01

425

Guide for conducting treatability studies under CERCLA: Chemical dehalogenation. Final report  

Microsoft Academic Search

Systematically conducted, well-documented treatability studies are an important component of the remedial investigation\\/feasibility study (RI\\/FS) process and the remedial design\\/remedial action (RD\\/RA) process under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The guide, which presents information on treatability studies involving chemical dehalogenation of soils and sludges, is intended to supplement the information in the final generic guide. The

McNelly

1992-01-01

426

Comparison of aquifer characterization approaches through steady state groundwater model validation: A controlled laboratory sandbox study  

USGS Publications Warehouse

Groundwater modeling has become a vital component to water supply and contaminant transport investigations. An important component of groundwater modeling under steady state conditions is selecting a representative hydraulic conductivity (K) estimate or set of estimates which defines the K field of the studied region. Currently, there are a number of characterization approaches to obtain K at various scales and in varying degrees of detail, but there is a paucity of information in terms of which characterization approach best predicts flow through aquifers or drawdowns caused by some drawdown inducing events. The main objective of this paper is to assess K estimates obtained by various approaches by predicting drawdowns from independent cross-hole pumping tests and total flow rates through a synthetic heterogeneous aquifer from flow-through tests. Specifically, we (1) characterize a synthetic heterogeneous aquifer built in the sandbox through various techniques (permeameter analyses of core samples, single-hole, cross-hole, and flow-through testing), (2) obtain mean K fields through traditional analysis of test data by treating the medium to be homogeneous, (3) obtain heterogeneous K fields through kriging and steady state hydraulic tomography, and (4) conduct forward simulations of 16 independent pumping tests and six flowthrough tests using these homogeneous and heterogeneous K fields and comparing them to actual data. Results show that the mean K and heterogeneous K fields estimated through kriging of small-scale K data (core and single-hole tests) yield biased predictions of drawdowns and flow rates in this synthetic heterogeneous aquifer. In contrast, the heterogeneous K distribution or ?K tomogram? estimated via steady state hydraulic tomography yields excellent predictions of drawdowns of pumping tests not used in the construction of the tomogram and very good estimates of total flow rates from the flowthrough tests. These results suggest that steady state groundwater model validation is possible in this laboratory sandbox aquifer if the heterogeneous K distribution and forcing functions (boundary conditions and source/sink terms) are characterized sufficiently. ?? 2010 by the American Geophysical Union.

Illman, W. A.; Zhu, J.; Craig, A. J.; Yin, D.

2010-01-01

427

Validation study of the Veratox R5 rapid ELISA for detection of gliadin.  

PubMed

Neogen Corp. developed the Veratox R5 Gliadin test kit for the detection of gliadin based on the monoclonal antibody R5 developed by Enrique Mendez (1). The purpose of this study was to validate the method under the requirements of the AOAC Research Institute Performance Tested Method program. There are two AOAC Official Methods for gluten detection in foods, 991.19 and 2012.01 (2), both of which are ELISAs. With the R5 Mendez method listed in the CODEX Alimentarius as a type 1 method for the detection of gluten in foods, the need to have additional rapid test kits validated by the AOAC Research Institute exists. PMID:23513967

Lupo, Anthony; Roebuck, Chris; Walsh, Aaron; Mozola, Mark; Abouzied, Mohamed

428

Construct validity of the functionally simulated technology task: an exploratory study.  

PubMed

ABSTRACT This study explored the construct validity of the Functional Simulated Technology Task (FSTT), online bill-pay version. The FSTT was administered to matched groups: persons with cognitive impairment and persons with no known cognitive impairment, established through the Montreal Cognitive Assessment (MoCA). Results indicated significance for construct validity by discriminating between the two groups. Results also indicated a good to excellent positive relationship between scores on the MoCA and the FSTT score areas of Outcome, Quality, Process, and Independence. The findings support the use of the FSTT to measure executive function using a simulated online bill-pay task. PMID:24102590

Cardell, Beth; Swain, Larissa J; Burnett, Amanda

2013-10-01

429

Cardiac conduction system abnormalities in ankylosing spondylitis: a cross-sectional study  

PubMed Central

Background Cardiac conduction disturbances are common in spondyloarthropathies such as ankylosing spondylitis (AS). Whether their occurrence can be linked to signs and symptoms of rheumatic disease activity is an unsettled issue addressed in this study. Methods In this cross-sectional study patients with AS according to modified New York criteria but without psoriasis, inflammatory bowel disease, dementia, pregnancy, other severe diseases such as malignancy and difficulties in answering questionnaires were invited; and 210 participated (120 men), mean age 49 years (SD 13; range: 16–77). Questionnaires, physical examination, ECG, and laboratory tests were performed at the same visit. Results Cardiac conduction disturbances were common and diagnosed in 10-33%, depending on if conservative or less conservative predefined criteria were applied. They consisted mostly of 1st degree atrio-ventricular block and prolonged QRS duration, but one patient had a pacemaker and 7 more had complete bundle branch blocks. Conduction abnormalities were associated mainly with age, male gender and body weight, and not with laboratory measures of inflammation or with Bath Ankylosing Spondylitis Disease Activity Index. Neither were they associated with the presence of HLA B27, which was found in 87% of all patients; the subtype B270502 dominated in all patients. Conclusions Cardiac conduction abnormalities are common in AS, but not associated with markers of disease activity or specific B27 subtypes. Even relatively mild conduction system abnormalities might, however, indirectly affect morbidity and mortality.

2013-01-01

430

Sleep in conduct-disordered adolescents--a polysomnographic and spectral power analysis study.  

PubMed

The aim of the present study was to characterize sleep in conduct-disordered adolescents using polysomnography and spectral power analysis. The two hypotheses were that conduct disorder would be associated with objective sleep problems, and that conduct disorder--as a precursor of adult antisocial personality disorder--would be associated with the same kind of abnormal sleep architecture, with both increased deep sleep and delta power, as previously reported in antisocial personality disorder. The patients consisted of 15 adolescents (age range 13-17 years, mean age 14.7 years) with histories of antisocial behavior so functionally impairing that they were ordered by child welfare to undergo a psychosocial evaluation in a closed social services ward. The healthy age-matched controls comprised 20 volunteers recruited with a newspaper advertisement. Opposite to earlier subjective sleep studies among conduct-disordered children, no significant differences in sleep parameters were observed between the two groups. The adolescents with conduct disorder slept a little bit longer, but the percentage amount of different sleep stages did not differ significantly between the two groups. Relative spectral power of sleep, delta power in particular, was similar in both groups, assessed in total sleep time as well as in first half of it. Different alternative explanations for these findings are discussed. PMID:18462804

Lindberg, Nina; Tani, Pekka; Sailas, Eila; Virkkala, Jussi; Urrila, Anna-Sofia; Virkkunen, Matti

2008-05-06

431

Predictive validity of the Biomedical Admissions Test: an evaluation and case study.  

PubMed

There has been an increase in the use of pre-admission selection tests for medicine. Such tests need to show good psychometric properties. Here, we use a paper by Emery and Bell [2009. The predictive validity of the Biomedical Admissions Test for pre-clinical examination performance. Med Educ 43:557-564] as a case study to evaluate and comment on the reporting of psychometric data in the field of medical student selection (and the comments apply to many papers in the field). We highlight pitfalls when reliability data are not presented, how simple zero-order associations can lead to inaccurate conclusions about the predictive validity of a test, and how biases need to be explored and reported. We show with BMAT that it is the knowledge part of the test which does all the predictive work. We show that without evidence of incremental validity it is difficult to assess the value of any selection tests for medicine. PMID:21182383

McManus, I C; Ferguson, Eamonn; Wakeford, Richard; Powis, David; James, David

2011-01-01

432

Quantification of tenatoprazole in rat plasma by HPLC: validation and its application to pharmacokinetic studies.  

PubMed

A simple, reliable HPLC method with UV detection (295 nm) in rat plasma was developed and validated for quantification of tenatoprazole, a novel proton pump inhibitor, which is in clinical trials. Following a single-step liquid-liquid extraction, the analyte and internal standard were separated using an isocratic mobile phase on a reverse phase C(18) column. The lower limit of quantitation was 20 ng/mL, with a relative standard deviation of less than 10%. A linear dynamic range of 20-6000 ng/mL was established. This HPLC method was validated with between-batch and within-batch precision of 2.9-6.3 and 1.4-5.8%, respectively. The between-batch and within-batch accuracy was 95.1-104.1 and 92.4-101.0%, respectively. This validated method is simple and repeatable enough to be used in pharmacokinetic studies. PMID:17590865

Nirogi, Ramakrishna; Kandikere, Vishwottam; Mudigonda, Koteshwara; Bhyrapuneni, Gopinadh

2007-12-01

433

Improved Diagnostic Validity of the ADOS Revised Algorithms: A Replication Study in an Independent Sample  

PubMed Central

Recently, Gotham et al. (2007) proposed revised algorithms for the Autism Diagnostic Observation Schedule (ADOS) with improved diagnostic validity. The aim of the current study was to replicate predictive validity, factor structure, and correlations with age and verbal and nonverbal IQ of the ADOS revised algorithms for Modules 1 and 2 in a large independent Dutch sample (N = 532). Results showed that the improvement of diagnostic validity was most apparent for autism, except in very young or low functioning children. Results for other autism spectrum disorders were less consistent. Overall, these findings support the use of the more homogeneous revised algorithms, with the use of similar items across developmental cells making it easier to compare ADOS scores within and between individuals.

Roos, Sascha; de Bildt, Annelies; Rommelse, Nanda; de Jonge, Maretha; Visser, Janne; Lappenschaar, Martijn; Swinkels, Sophie; van der Gaag, Rutger Jan; Buitelaar, Jan

2010-01-01

434

The validity of post-concussion syndrome in children: A controlled historical cohort study  

Microsoft Academic Search

The aim of this controlled historical cohort study was to assess the validity of post-concussion syndrome in children. We identified 301 children aged 4–15 years who had sustained an isolated brain concussion, and another group of 301 children who sustained any other mild body injury excluding the head. Parents from both groups filled in standardized questionnaires containing questions about the

Olga Nacajauskaite; Milda Endziniene; Kristina Jureniene; Harald Schrader

2006-01-01

435

Functional cooking skills and neuropsychological functioning in patients with stroke: An ecological validity study  

Microsoft Academic Search

Efforts to relate neuropsychological performance to real-world task functioning have predominantly yielded lackluster results, typically with neuropsychological performance accounting for modest amounts of variance in function. Nonetheless, the ecological validity of neuropsychological measures for predicting functional abilities remains a strong research interest and clinical necessity. This study relates neuropsychological performance to performance on a standardised cooking task (Rabideau Kitchen Evaluation

Christine L. Yantz; Doug Johnson-Greene; Christopher Higginson; Lindsay Emmerson

2010-01-01

436

Construct Validation of Optimism and Pessimism in Older Men: Findings From the Normative Aging Study  

Microsoft Academic Search

Validation of Scheier and Carver's (1985) Life Orientation Test (LOT) has identified associations between bipolar optimism and several external constructs. However, optimism and pessimism may be not bipolar, but rather separate constructs. Furthermore, these constructs may be indistinguishable from personality traits, such as neuroticism and extraversion. This study examined the associations of separate optimism and pessimism measures with self-reports of

Daniel K. Mroczek; Avron Spiro; Carolyn M. Aldwin; Daniel J. Ozer; Raymond Bossé

1993-01-01

437

Validation of the Maslach Burnout Inventory - General Survey: An Internet Study  

Microsoft Academic Search

This study examined the factorial validity of the Maslach Burnout Inventory - General Survey (MBI-GS; Schaufeli et al ., Maslach Burnout Inventory Manual , pp. 19-26. Consulting Psychologists Press, CA) in eight different occupational groups of employees ( N = 2919), who were recruited through the Internet. Results of multi-group confirmatory factor analyses favored the proposed Three-Factor Model over alternative

Arnold B. Bakker; Evangelia Demerouti; Wilmar B. Schaufeli

2002-01-01

438

Validation Studies of the Physical Activity Scale for the Elderly (PASE)  

Cancer.gov

Validation Studies of the Physical Activity Scale for the Elderly (PASE) Harada et al. 2001 Bonnefoy et al. 2001 Washburn et al. 1999 Washburn et al. 1999 Washburn et al. 1993 Harada et al. 2001 See reference #23 Methods Relationship between PASE and

439

Border College Consortium Descriptive Test of English Skills and Verbal Aptitude Test: Norming and Validation Study.  

ERIC Educational Resources Information Center

The background and rationale for the 2 tests are described and results of a norming and validation study involving 804 Mexican-American college freshmen in 5 border community colleges are reported. The results provide evidence that the DTES and VAT are reliable and effective for Mexican-American students, having overcome inadequacies of other…

Karathanos, Demetrius

1991-01-01

440

A Predictive Validity Study of the Learning Style Questionnaire (LSQ) Using Multiple, Specific Learning Criteria  

ERIC Educational Resources Information Center

|Multiple and specific learning criteria were used to examine the predictive validity of the Learning Style Questionnaire (LSQ). Ninety-nine students in a college of higher learning in The Netherlands participated in a naturally occurring field study. The students were categorized into one of four LSQ dimensions, namely, Activists, Theorists,…

Kappe, F. R.; Boekholt, L.; den Rooyen, C.; Van der Flier, H.

2009-01-01

441

Standards-Based Performance Assessment for the Evaluation of Student Teachers: A Consequential Validity Study  

ERIC Educational Resources Information Center

|The instrument Samples of Teaching Performance (STP) was developed to assess student teachers' capacity to plan, deliver and evaluate a unit of instruction. The current study reports consequential validity data collected from supervisors (n = 20) and student teachers (n = 62) from three elementary and five secondary teacher preparation programs…

Montecinos, Carmen; Rittershaussen, Sylvia; Solis, Maria Cristina; Contreras, Ines; Contreras, Claudia

2010-01-01

442

A Construct Validation Study of Phonological Awareness for Children Entering Prekindergarten  

ERIC Educational Resources Information Center

|The purpose of this study was to determine the psychometric characteristics of a phonological awareness assessment for prekindergarten children using Messick's (1989) framework for unitary construct validity. Upon entry into prekindergarten, children were given rhyme discrimination, syllable segmentation, initial phoneme isolation, and phoneme…

Webb, Mi-Young Lee; Schwanenflugel, Paula J.; Kim, Seock-Ho

2004-01-01

443

A validation study of the hospital anxiety and depression scale (HADS) in a Spanish population  

Microsoft Academic Search

The present study aims to validate the Spanish version of the Hospital Anxiety and Depression Scale (HADS) and to determine the use of this tool for screening mood and anxiety disorders. Psychometric properties of the HADS were assessed in different groups of general medical outpatients attending the Hospital Clínic in Barcelona (N=385), and psychiatric diagnoses were made using DSM-IV criteria.

M. J. Herrero; J. Blanch; J. M. Peri; J. De Pablo; L. Pintor; A. Bulbena

2003-01-01

444

The Arabic Version of the Mayo-Portland Adaptability Inventory 4: A Validation Study  

ERIC Educational Resources Information Center

|The Mayo-Portland Adaptability Inventory 4 (MPAI-4) is a valid and reliable assessment tool to detect clinical impairments in patients with acquired brain injury. The tool is widely used by rehabilitation therapists worldwide, given its good psychometric properties and its availability in several languages. The purpose of this study was to…

Hamed, Razan; Tariah, Hashem Abu; Malkawi, Somaya; Holm, Margo B.

2012-01-01

445

The Arabic Version of the Mayo-Portland Adaptability Inventory 4: A Validation Study  

ERIC Educational Resources Information Center

The Mayo-Portland Adaptability Inventory 4 (MPAI-4) is a valid and reliable assessment tool to detect clinical impairments in patients with acquired brain injury. The tool is widely used by rehabilitation therapists worldwide, given its good psychometric properties and its availability in several languages. The purpose of this study was to…

Hamed, Razan; Tariah, Hashem Abu; Malkawi, Somaya; Holm, Margo B.

2012-01-01

446

A Construct Validity Study of Clinical Competence: A Multitrait Multimethod Matrix Approach  

ERIC Educational Resources Information Center

|Introduction: The purpose of the study was to adduce evidence for estimating the construct validity of clinical competence measured through assessment instruments used for high-stakes examinations. Methods: Thirty-nine international physicians (mean age = 41 + 6.5 y) participated in high-stakes examination and 3-month supervised clinical practice…

Baig, Lubna; Violato, Claudio; Crutcher, Rodney

2010-01-01

447

Validity Study of the Autism Spectrum Disorders-Diagnostic for Children (ASD-DC)  

ERIC Educational Resources Information Center

The Autism Spectrum Disorders-Diagnostic for Children (ASD-DC) is a 40-item Likert format scale designed to serve in the diagnosis of children and adolescents from 2 to 16 years of age. The reliability and factor structure of the scale have been established in previous research. Studies 1 and 2 were designed to evaluate the validity of the measure…

Matson, Johnny L.; Gonzalez, Melissa; Wilkins, Jonathan

2009-01-01

448

A validation study for the Problem Solving Inventory on an adolescent population  

Microsoft Academic Search

This study attempted to validate a modified version of Heppner & Petersen's (1982) Problem Solving Inventory, (PSI) for a younger adolescent population with specific emphasis on its potential uses with Learning Disabled adolescents.^ Results indicate the Problem Solving Inventory was not useful in differentiating Learning Disabled from non-Learning Disabled youngsters. Since the self-appraisal of interpersonal problem solving ability of Learning

Bernard Anthony Corda

1991-01-01

449

A Validation Study of a Georgia Teacher Certification Test Using Confirmatory Factor Analysis.  

ERIC Educational Resources Information Center

|This study investigated the construct validity of the revised Special Education-Mental Handicaps Georgia Teacher Certification Test (MH-TCT) using hierarchical confirmatory factor analysis and LISREL VI. The primary objective was to determine whether first-order and second-order factors correspond to item/objective/test relationships defined by…

Dabney, Marian E.; Stewart, Theadora

450

Toward validation of atypical depression in the community: results of the Zurich cohort study  

Microsoft Academic Search

Aims: This paper (1) examines the validity of the atypical subtype of depression in a community-based longitudinal cohort study, (2) presents estimates of the prevalence and sex differences of DSM-IV atypical depression and a newly more broadly defined atypical syndrome in the community and (3) compares the clinical correlates and treatment patterns of those with atypical depression with other depressives.

Jules Angst; Alex Gamma; Robert Sellaro; Heping Zhang; Kathleen Merikangas

2002-01-01

451

Validation Studies of the Ainsworth New Physical Activity Questionnaire (N-PAQ)  

Cancer.gov

Validation Studies of the Ainsworth New Physical Activity Questionnaire (N-PAQ) Ainsworth et al. 2000 See reference #01 Methods Relationships between N-PAQ and PA log (PAL), CSA monitor derived counts/d and moderate intensity scores using equations from:

452

Standards-Based Performance Assessment for the Evaluation of Student Teachers: A Consequential Validity Study  

ERIC Educational Resources Information Center

The instrument Samples of Teaching Performance (STP) was developed to assess student teachers' capacity to plan, deliver and evaluate a unit of instruction. The current study reports consequential validity data collected from supervisors (n = 20) and student teachers (n = 62) from three elementary and five secondary teacher preparation programs…

Montecinos, Carmen; Rittershaussen, Sylvia; Solis, Maria Cristina; Contreras, Ines; Contreras, Claudia

2010-01-01

453

Validity Study of the Autism Spectrum Disorders-Diagnostic for Children (ASD-DC)  

ERIC Educational Resources Information Center

|The Autism Spectrum Disorders-Diagnostic for Children (ASD-DC) is a 40-item Likert format scale designed to serve in the diagnosis of children and adolescents from 2 to 16 years of age. The reliability and factor structure of the scale have been established in previous research. Studies 1 and 2 were designed to evaluate the validity of the…

Matson, Johnny L.; Gonzalez, Melissa; Wilkins, Jonathan

2009-01-01

454

Cross-cultural validation of the child abuse potential inventory in Greece: A preliminary study  

Microsoft Academic Search

Objective: The aim of this study was first, to provide preliminary findings on the reliability and validity of a Greek translation of the CAP Inventory (Milner, 1986), and second, to examine whether there were any differences between Greek and American scores in the CAP Inventory.Method: A convenience sample of 320 Greek parents was recruited from the outpatient unit of a

Stella Tsitoura

1997-01-01

455

Validation Studies of the The Modifiable Activity Questionnaire (MAQ)/Pima Indian Questionnaire  

Cancer.gov

Validation Studies of the The Modifiable Activity Questionnaire (MAQ)/Pima Indian Questionnaire Kriska et al. 1990 See reference #44 Methods Relationships between the MAQ and past wk Caltrac activity monitor (counts/h) at test and retest (Spearman correlations) Sample 17

456

Cross-validation and calibration of Jackson-Pollock equations with DXA: the TIGER study  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Jackson-Pollock (J&P) body composition equations were developed primarily from data on white men and women using hydrostatically determined body density (BD) as the criterion measure. This study cross-validated the J&P equations with ethnically diverse subjects and percent fat (%fat) determined ...

457

A Comparative Study of Adolescent Risk Assessment Instruments: Predictive and Incremental Validity  

ERIC Educational Resources Information Center

|Promising new adolescent risk assessment tools are being incorporated into clinical practice but currently possess limited evidence of predictive validity regarding their individual and/or combined use in risk assessments. The current study compares three structured adolescent risk instruments, Youth Level of Service/Case Management Inventory…

Welsh, Jennifer L.; Schmidt, Fred; McKinnon, Lauren; Chattha, H. K.; Meyers, Joanna R.

2008-01-01

458

Validating the Student Developmental Task and Lifestyle Assessment: A Longitudinal Study.  

ERIC Educational Resources Information Center

Study assessed the effectiveness of the Student Developmental Task and Lifestyle Assessment (SDTLA) in measuring psychosocial changes from the freshman year through the senior year using longitudinal research design. Results provide evidence of validity for the SDTLA and demonstrate that as a measurement tool, the SDTLA is sensitive to changes…

Wachs, Peter M.; Cooper, Diane L.

2002-01-01

459

A Comparative Study of Adolescent Risk Assessment Instruments: Predictive and Incremental Validity  

ERIC Educational Resources Information Center

Promising new adolescent risk assessment tools are being incorporated into clinical practice but currently possess limited evidence of predictive validity regarding their individual and/or combined use in risk assessments. The current study compares three structured adolescent risk instruments, Youth Level of Service/Case Management Inventory…

Welsh, Jennifer L.; Schmidt, Fred; McKinnon, Lauren; Chattha, H. K.; Meyers, Joanna R.

2008-01-01

460

The Attitudes Toward Women Scale for Adolescents (AWSA): A study of reliability and validity  

Microsoft Academic Search

This study describes the development of the Attitudes Toward Women Scale for Adolescents (AWSA), an instrument based on the short form of the Spence-Helmreich Attitudes Toward Women Scale (AWS). The AWSA has been tested in four samples of adolescents. Internal consistency estimates and test-retest stability indicated high reliability. Hypotheses formulated to test the construct validity of the scale were largely

Nancy L. Galambos; Anne C. Petersen; Maryse Richards; Idy B. Gitelson

1985-01-01

461

The Self Concept as a Learner Inventory: A Cross-Validation Study.  

ERIC Educational Resources Information Center

The validity of the Self Concept as a Learner Revised (SCALR) inventory was studied. The construct issue of academic self-concept was explored by comparing the SCALR to the academic portion of the Multidimensional Self Concept Scale (MSCS). The SCALR contains 44 items (four scales of 11 items each). The SCALR version for grades 7 through 12 was…

Barisa, Mark; And Others

462

Validation Studies of the National Health Interview Survey (NHIS)-walking questions  

Cancer.gov

Validation Studies of the National Health Interview Survey (NHIS)-walking questions Rauh et al. 1992 Hovell et al. 1992 Weiss et al. 1990 Rauh et al. 1992 See reference #12 Methods Relationship between items on the NHIS Walking items and Caltrac (Pearson

463

A psychometric study of the Adult Attachment Interview: Reliability and discriminant validity  

Microsoft Academic Search

The Adult Attachment Interview (AAI) stimulates Ss to retrieve and evaluate attachment- related autobiographical memories and has increasingly been used to predict the quality of parent—child interactions and infant—parent attachment relationships. Its reliability and discriminant validity, however, have not yet been examined. In this study, 83 mothers were interviewed twice, 2 months apart, by different interviewers so that the instrument's

Marian J. Bakermans-Kranenburg; Marinus H. Van IJzendoorn

1993-01-01

464

Ethical Constraints in the Valid Interpretation of Transcribed Communication in Online Study  

ERIC Educational Resources Information Center

|This paper discusses the ethical issues associated with analysis of computer conference transcripts and the value of validating the interpretations of such transcripts with other data sources. Based on the study of a graduate level online course recently taught at a major American public university, this paper attempts to demonstrate how failures…

Santos, Ieda; LeBaron, John

2006-01-01

465

Transcranial Doppler Measurement of Middle Cerebral Artery Blood Flow Velocity: A Validation Study  

Microsoft Academic Search

SUMMARY Measurement of intracranial arterial blood flow velocity is a new technique with potentially a number of very useful applications. This study validates the technique by comparing it to cerebral blood flow (CBF) measured using intravenous Xenon and extracranial clearance recording. We have measured the middle cerebral artery (MCA) blood flow velocity in 17 symptomatic patients with the EME TC

C. C. R. BISHOP; S. POWELL; D. RUTT; L. BROWSE

2010-01-01

466

Validation Studies of the Physical Activity Scale for the Elderly (PASE)  

Cancer.gov

Validation Studies of the Physical Activity Scale for the Elderly (PASE) Dinger et al. 2004 See reference #79 Methods PASE compared to accelerometry (Spearman correlations) Sample 43 female, 23 male subjects (age = 75.7 ± 7.9 years Summary Results Actigraph

467

Validation Studies of the International Physical Activity Questionnaire (IPAQ) Short, Last 7-day  

Cancer.gov

Validation Studies of the International Physical Activity Questionnaire (IPAQ) Short, Last 7-day Ekelund et al. 2006 Fogelholm et al. 2006 Kolbe-Alexander et al. 2006 Macfarlane et al. 2007 Ekelund et al. 2006 See reference #81 Methods Relation of IPAQ-short

468

Preliminary Face and Construct Validation Study of a Virtual Basic Laparoscopic Skill Trainer  

PubMed Central

Abstract Background The Virtual Basic Laparoscopic Skill Trainer (VBLaST™) is a developing virtual-reality–based surgical skill training system that incorporates several of the tasks of the Fundamentals of Laparoscopic Surgery (FLS) training system. This study aimed to evaluate the face and construct validity of the VBLaST™ system. Materials and Methods Thirty-nine subjects were voluntarily recruited at the Beth Israel Deaconess Medical Center (Boston, MA) and classified into two groups: experts (PGY 5, fellow and practicing surgeons) and novice (PGY 1–4). They were then asked to perform three FLS tasks, consisting of peg transfer, pattern cutting, and endoloop, on both the VBLaST and FLS systems. The VBLaST performance scores were automatically computed, while the FLS scores were rated by a trained evaluator. Face validity was assessed using a 5-point Likert scale, varying from not realistic/useful (1) to very realistic/useful (5). Results Face-validity scores showed that the VBLaST system was significantly realistic in portraying the three FLS tasks (3.95?±?0.909), as well as the reality in trocar placement and tool movements (3.67?±?0.874). Construct-validity results show that VBLaST was able to differentiate between the expert and novice group (P?=?0.015). However, of the two tasks used for evaluating VBLaST, only the peg-transfer task showed a significant difference between the expert and novice groups (P?=?0.003). Spearman correlation coefficient analysis between the two scores showed significant correlation for the peg-transfer task (Spearman coefficient 0.364; P?=?0.023). Conclusions VBLaST demonstrated significant face and construct validity. A further set of studies, involving improvement to the current VBLaST system, is needed to thoroughly demonstrate face and construct validity for all the tasks.

Sankaranarayanan, Ganesh; Lin, Henry; Arikatla, Venkata S.; Mulcare, Maureen; Zhang, Likun; Derevianko, Alexandre; Lim, Robert; Fobert, David; Cao, Caroline; Schwaitzberg, Steven D.; Jones, Daniel B.

2010-01-01

469

Interactions Between the Cationic Surfactants Bearing Different Polar Head Groups: Interfacial, Conductivity, NMR, and Fluorescence Studies  

Microsoft Academic Search

Interfacial tension (?), conductivity (?), nuclear magnetic resonance (NMR), and fluorescence measurements have been carried out to study the mixed interfacial and micellar behavior of cationic surfactants cetyltributylphosphonium bromide (CTBB) and the cetyltrimethylammonium bromide (CTAB). From the ? versus log Cs plots, the values of critical micellar concentration (cmc) and various interfacial parameters were computed. From ? measurements, the equivalent

Pankaj Sehgal; Reinhard Wimmer; Jesper E. Mogensen; Hidekazu Doe

2007-01-01

470

A comparative study on preparation of conductive and transparent carbon nanotube thin films  

Microsoft Academic Search

In this study we evaluated the optoelectronic performance of transparent conductive films of carbon nanotubes from the various commercial carbon nanotube materials and the different preparation methods. The sheet resistance and the optical transmittance can have a significant difference for the different carbon nanotubes. According to the thermogravimetric analysis and Raman spectra, we found that the optoelectronic performance of commercial

Bo-Tau Liu; Chao-Hsiang Hsu; Wei-Hong Wang

471

Molecular Dynamics Study of Gating in the Mechanosensitive Channel of Small Conductance MscS  

Microsoft Academic Search

Mechanosensitive channels are a class of ubiquitous membrane proteins gated by mechanical strain in the cellular membrane. MscS, the mechanosensitive channel of small conductance, is found in the inner membrane of Escherichia coli and its crystallographic structure in an open form has been recently solved. By means of molecular dynamics simulations we studied the stability of the channel conformation suggested

Marcos Sotomayor; Klaus Schulten

2004-01-01

472

Study of thermally reworkable epoxy materials and thermal conductivity enhancement using carbon fiber for electronics packaging  

Microsoft Academic Search

Epoxy resins are widely used as the underfill materials for the integrated circuit (IC) chips for the reliability enhancement and as the binder of electrically conductive adhesives (ECA). However, cured epoxy materials are infusible and insoluble networks which is a problem for the repair of a printed circuit board assembly packaged with epoxy materials. In this study, six diepoxides containing

Haiying Li

2003-01-01

473

Analysis of the Air Force ISO 14001 Pilot Study Conducted by DoD.  

National Technical Information Service (NTIS)

The Department of Defense (DoD) conducted an ISO 14001 pilot study with the primary goal of determining how ISO 14001 could help DoD organizations reduce risks, improve compliance with environmental regulations, enhance stewardship, contain costs, and mee...

R. C. Harris

2000-01-01

474

It's all about relationships: A qualitative study of health researchers' perspectives of conducting interdisciplinary health research  

Microsoft Academic Search

BACKGROUND: Interdisciplinary research has been promoted as an optimal research paradigm in the health sciences, yet little is known about how researchers experience interdisciplinarity in practice. This study sought to determine how interdisciplinary research was conceptualized and operationalized from the researcher's perspective and to better understand how best to facilitate interdisciplinary research success. METHODS: Key informant interviews were conducted with

Kalpana M Nair; Lisa Dolovich; Kevin Brazil; Parminder Raina

2008-01-01

475

Optical conductivity and kinetic energy of the superconducting state: A cluster dynamical mean field study  

Microsoft Academic Search

We study the evolution of the optical conductivity in the t-J model with temperature and doping using the Cluster Dynamical Mean Field Method. The transition to the superconducting state in the overdoped regime is characterized by an increase in the kinetic energy of the system, in contrast to the underdoped side where kinetic energy of the system decreases upon condensation.

K. Haule; G. Kotliar

2007-01-01

476

Acoustical and thermal conductivity studies on CuO/DEA-benzene hybrid nanofluids  

NASA Astrophysics Data System (ADS)

Binary organic liquid based copper oxide nanofluids of various concentrations have been prepared through ultrasonically assisted chemical solution method. Ultrasonic studies, refractive indices, densities are carried out for the nanofluids for various temperature where Thermal conductivity was also measured for the nanofluids at room temperature. The molecular interactions responsible for the changes in acoustical parameters with respect to concentration and temperature are discussed.

Rohini, B.; Gopalakrishnan, M.; Kiruba, R.; Mahalingam, T.; Kingson Solomon Jeevaraj, A.

2013-02-01