Science.gov

Sample records for validation studies conducted

  1. A Framework for Conducting ESL/EFL Construct Validation Studies.

    ERIC Educational Resources Information Center

    Mouw, John T.; Perkins, Kyle

    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 theory,…

  2. Conducting ecologically valid prevention research: recruiting and retaining a "whole village" in multimethod, multiagent studies.

    PubMed

    Capaldi, D M; Chamberlain, P; Fetrow, R A; Wilson, J E

    1997-08-01

    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 on their degree of involvement. Issues of recruitment and retention thus are magnified in multimethod, multiagent studies. To illustrate these issues, findings are presented for three studies conducted with risk populations in the past decade at the Oregon Social Learning Center: a passive longitudinal study, a selected prevention study, and an indicated prevention study. Findings indicate that achieving high recruitment and retention rates for at-risk and high-risk subjects in multisetting studies is possible, and that a developmental approach should be taken to recruiting risk populations. PMID:9338955

  3. Validation of a one-stop carpal tunnel clinic including nerve conduction studies and hand therapy

    PubMed Central

    Ball, C; Pearse, M; Kennedy, D; Hall, A; Nanchahal, J

    2011-01-01

    INTRODUCTION Carpal tunnel syndrome is the most common hand disorder. We describe a pathway that includes clinical assessment, neurophysiological testing, surgery and physical therapy all at the same visit. METHODS All referrals for carpal tunnel syndrome were screened for inclusion in a ‘one-stop’ surgeon-led clinic. Prospective clinical data collected included patient reported outcome measures and satisfaction scores, touch threshold, pinch and grip strength. Patients were assessed clinically, underwent nerve conduction studies and surgery as indicated, all on the same day. Baseline and one-year follow-up data were analysed for 57 patients (62 hands). RESULTS There was significant improvement in all domains of the Boston Carpal Tunnel and Michigan Hand Outcomes questionnaires, grip strength and touch threshold. There were no adverse events. The total mean operating time was 12.8 minutes (range: 5–15 minutes) and the mean tourniquet time was 2.5 minutes (range: 1–11 minutes). Using a dual theatre model produced a short mean turnaround time of 14.8 minutes (range: 2–37 minutes). Patient satisfaction as judged using a Picker questionnaire was very high. CONCLUSIONS A highly efficient clinical service involving both diagnostics and treatment can be delivered at a single hospital visit while maintaining optimal outcomes and high patient satisfaction. PMID:22041242

  4. Quantum Mechanics Studies of Fuel Cell Catalysts and Proton Conducting Ceramics with Validation by Experiment

    NASA Astrophysics Data System (ADS)

    Tsai, Ho-Cheng

    We carried out quantum mechanics (QM) studies aimed at improving the performance of hydrogen fuel cells. In part I, The challenge was to find a replacement for the Pt cathode that would lead to improved performance for the Oxygen Reduction Reaction (ORR) while remaining stable under operational conditions and decreasing cost. Our design strategy was to find an alloy with composition Pt3M that would lead to surface segregation such that the top layer would be pure Pt, with the second and subsequent layers richer in M. Under operating conditions we expect the surface to have significant O and/or OH chemisorbed on the surface; we searched for M that would remain segregated under these conditions. Using QM we examined surface segregation for 28 Pt3M alloys, where M is a transition metal. We found that only Pt3Os and Pt3Ir showed significant surface segregation when O and OH are chemisorbed on the catalyst surfaces. This result indicates that Pt3Os and Pt 3Ir favor formation of a Pt-skin surface layer structure that would resist the acidic electrolyte corrosion during fuel cell operation environments. We chose to focus on Os because the phase diagram for Pt-Ir indicated that Pt-Ir could not form a homogeneous alloy at lower temperature. To determine the performance for ORR, we used QM to examine intermediates, reaction pathways, and reaction barriers involved in the processes for which protons from the anode reactions react with O2 to form H2O. These QM calculations used our Poisson-Boltzmann implicit solvation model include the effects of the solvent (water with dielectric constant 78 with pH 7 at 298K). We also carried out similar QM studies followed by experimental validation for the Os/Pt core-shell catalyst fabricated by the underpotential deposition (UPD) method. The QM results indicated that the RDS for ORR is a compromise between the OOH formation step (0.37 eV for Pt, 0.23 eV for Pt2ML/Os core-shell) and H2O formation steps (0.32 eV for Pt, 0.22 eV for Pt2ML /Os core-shell). We found that Pt2ML/Os has the highest activity (compared to pure Pt and to the Pt3Os alloy) because the 0.37 eV barrier decreases to 0.23 eV. To understand what aspects of the core shell structure lead to this improved performance, we considered the effect on ORR of compressing the alloy slab to the dimensions of pure Pt. However this had the same RDS barrier 0.37 eV. Experimental materials characterization proves the core-shell feature of our catalyst. In part II, we used QM calculations to study methane stream reforming on a Ni-alloy catalyst surfaces for solid oxide fuel cell (SOFC) application. SOFC has wide fuel adaptability but the coking and sulfur poisoning will reduce its stability. We carried out QM calculations on surface segregation and found that the most stable configuration for Ni4Fe has a Fe atom distribution of (0%, 50%, 25%, 25%, 0%) starting at the bottom layer. We calculated that the binding of C atoms on the Ni4Fe surface is 142.9 Kcal/mol, which is about 10 Kcal/mol weaker compared to the pure Ni surface. This result confirms the experimental observation. The reaction energy barriers for CH x decomposition and C binding on various alloy surface, Ni4X (X=Fe, Co, Mn, and Mo), showed Ni4Fe, Ni4Co, and Fe4Mn all have better coking resistance than pure Ni, but that only Ni4Fe and Fe4Mn have (slightly) improved activity compared to pure Ni. In part III, we used QM to examine the proton transport in doped perovskite-ceramics. Here we used a 2x2x2 supercell of perovskite with composition Ba8X 7M1(OH)1O23 where X=Ce or Zr and M=Y, Gd, or Dy. Thus in each case a 4+ X is replace by a 3 + M plus a proton on one O. Here we predicted the barriers for proton diffusion allowing both includes intra-octahedron and inter-octahedra proton transfer. Without any restriction, we only observed the inter-octahedra proton transfer with similar energy barrier as previous computational work but 0.2 eV higher than experimental result for Y doped zirconate. For one restriction in our calculations is that the Odonor-Oacceptor atoms were kept at fixed distances, we found that the barrier difference between cerates/zirconates with various dopants are only 0.02~0.03 eV. To fully address performance one would need to examine proton transfer at grain boundaries, which will require larger scale ReaxFF reactive dynamics for systems with millions of atoms. The QM calculations used here will be used to train the ReaxFF force field. (Abstract shortened by UMI.).

  5. Threats to Validity in the Design and Conduct of Preclinical Efficacy Studies: A Systematic Review of Guidelines for In Vivo Animal Experiments

    PubMed Central

    Henderson, Valerie C.; Kimmelman, Jonathan; Fergusson, Dean; Grimshaw, Jeremy M.; Hackam, Dan G.

    2013-01-01

    Background The vast majority of medical interventions introduced into clinical development prove unsafe or ineffective. One prominent explanation for the dismal success rate is flawed preclinical research. We conducted a systematic review of preclinical research guidelines and organized recommendations according to the type of validity threat (internal, construct, or external) or programmatic research activity they primarily address. Methods and Findings We searched MEDLINE, Google Scholar, Google, and the EQUATOR Network website for all preclinical guideline documents published up to April 9, 2013 that addressed the design and conduct of in vivo animal experiments aimed at supporting clinical translation. To be eligible, documents had to provide guidance on the design or execution of preclinical animal experiments and represent the aggregated consensus of four or more investigators. Data from included guidelines were independently extracted by two individuals for discrete recommendations on the design and implementation of preclinical efficacy studies. These recommendations were then organized according to the type of validity threat they addressed. A total of 2,029 citations were identified through our search strategy. From these, we identified 26 guidelines that met our eligibility criteria—most of which were directed at neurological or cerebrovascular drug development. Together, these guidelines offered 55 different recommendations. Some of the most common recommendations included performance of a power calculation to determine sample size, randomized treatment allocation, and characterization of disease phenotype in the animal model prior to experimentation. Conclusions By identifying the most recurrent recommendations among preclinical guidelines, we provide a starting point for developing preclinical guidelines in other disease domains. We also provide a basis for the study and evaluation of preclinical research practice. Please see later in the article for the Editors' Summary PMID:23935460

  6. Conducting Student Retention Studies.

    ERIC Educational Resources Information Center

    Ewell, Peter T.

    Techniques for conducting student-attrition studies using the Student-Outcomes Information Service (SOIS) are outlined. General concepts to effectively guide an institutional research effort are discussed, with attention to better defining student attrition and a summary of results of recent research on the reasons why students withdraw from…

  7. Carbon Fibers Conductivity Studies

    NASA Technical Reports Server (NTRS)

    Yang, C. Y.; Butkus, A. M.

    1980-01-01

    In an attempt to understand the process of electrical conduction in polyacrylonitrile (PAN)-based carbon fibers, calculations were carried out on cluster models of the fiber consisting of carbon, nitrogen, and hydrogen atoms using the modified intermediate neglect of differential overlap (MINDO) molecular orbital (MO) method. The models were developed based on the assumption that PAN carbon fibers obtained with heat treatment temperatures (HTT) below 1000 C retain nitrogen in a graphite-like lattice. For clusters modeling an edge nitrogen site, analysis of the occupied MO's indicated an electron distribution similar to that of graphite. A similar analysis for the somewhat less stable interior nitrogen site revealed a partially localized II electron distribution around the nitrogen atom. The differences in bonding trends and structural stability between edge and interior nitrogen clusters led to a two-step process proposed for nitrogen evolution with increasing HTT.

  8. Developing and Validating the Youth Conduct Problems Scale-Rwanda: A Mixed Methods Approach

    PubMed Central

    Ng, Lauren C.; Kanyanganzi, Frederick; Munyanah, Morris; Mushashi, Christine; Betancourt, Theresa S.

    2014-01-01

    This study developed and validated the Youth Conduct Problems Scale-Rwanda (YCPS-R). Qualitative free listing (n = 74) and key informant interviews (n = 47) identified local conduct problems, which were compared to existing standardized conduct problem scales and used to develop the YCPS-R. The YCPS-R was cognitive tested by 12 youth and caregiver participants, and assessed for test-retest and inter-rater reliability in a sample of 64 youth. Finally, a purposive sample of 389 youth and their caregivers were enrolled in a validity study. Validity was assessed by comparing YCPS-R scores to conduct disorder, which was diagnosed with the Mini International Neuropsychiatric Interview for Children, and functional impairment scores on the World Health Organization Disability Assessment Schedule Child Version. ROC analyses assessed the YCPS-R's ability to discriminate between youth with and without conduct disorder. Qualitative data identified a local presentation of youth conduct problems that did not match previously standardized measures. Therefore, the YCPS-R was developed solely from local conduct problems. Cognitive testing indicated that the YCPS-R was understandable and required little modification. The YCPS-R demonstrated good reliability, construct, criterion, and discriminant validity, and fair classification accuracy. The YCPS-R is a locally-derived measure of Rwandan youth conduct problems that demonstrated good psychometric properties and could be used for further research. PMID:24949628

  9. Validation Studies for the Diet History Questionnaire II

    Cancer.gov

    Data show that the DHQ I instrument provides reasonable nutrient estimates, and three studies were conducted to assess its validity/calibration. There have been no such validation studies with the DHQ II.

  10. How to Conduct Multimethod Field Studies in the Operating Room: The iPad Combined With a Survey App as a Valid and Reliable Data Collection Tool

    PubMed Central

    Tscholl, David W; Weiss, Mona; Spahn, Donat R

    2016-01-01

    Background Tablet computers such as the Apple iPad are progressively replacing traditional paper-and-pencil-based data collection. We combined the iPad with the ready-to-use survey software, iSurvey (from Harvestyourdata), to create a straightforward tool for data collection during the Anesthesia Pre-Induction Checklist (APIC) study, a hospital-wide multimethod intervention study involving observation of team performance and team member surveys in the operating room (OR). Objective We aimed to provide an analysis of the factors that led to the use of the iPad- and iSurvey-based tool for data collection, illustrate our experiences with the use of this data collection tool, and report the results of an expert survey about user experience with this tool. Methods We used an iPad- and iSurvey-based tool to observe anesthesia inductions conducted by 205 teams (N=557 team members) in the OR. In Phase 1, expert raters used the iPad- and iSurvey-based tool to rate team performance during anesthesia inductions, and anesthesia team members were asked to indicate their perceptions after the inductions. In Phase 2, we surveyed the expert raters about their perceptions regarding the use of the iPad- and iSurvey-based tool to observe, rate, and survey teams in the ORs. Results The results of Phase 1 showed that training data collectors on the iPad- and iSurvey-based data collection tool was effortless and there were no serious problems during data collection, upload, download, and export. Interrater agreement of the combined data collection tool was found to be very high for the team observations (median Fleiss’ kappa=0.88, 95% CI 0.78-1.00). The results of the follow-up expert rater survey (Phase 2) showed that the raters did not prefer a paper-and-pencil-based data collection method they had used during other earlier studies over the iPad- and iSurvey-based tool (median response 1, IQR 1-1; 1=do not agree, 2=somewhat disagree, 3=neutral, 4=somewhat agree, 5=fully agree). They found the iPad (median 5, IQR 4.5-5) and iSurvey (median 4, IQR 4-5) to be working flawlessly and easy to use (median 5, IQR 4-5). Expert ratings also showed that the anesthesia team members (ie, the surveyed doctors and nurses) who used the iPad- and iSurvey-based tool in the OR liked it (median 4, IQR 3-4.5). Conclusions The combination of the iPad and iSurvey provides an efficient and unobtrusive method to observe teams in their natural environment in the OR and to survey team members immediately after completing their task (ie, anesthesia induction). The expert raters positively evaluated the use of the device and user perceptions. Considering these comprehensive results, we can recommend the use of the iPad- and iSurvey-based tool for studying team performance and team member perceptions in the OR. PMID:26732090

  11. Validation studies and proficiency testing.

    PubMed

    Ankilam, Elke; Heinze, Petra; Kay, Simon; Van den Eede, Guy; Popping, Bert

    2002-01-01

    Genetically modified organisms (GMOs) entered the European food market in 1996. Current legislation demands the labeling of food products if they contain <1% GMO, as assessed for each ingredient of the product. To create confidence in the testing methods and to complement enforcement requirements, there is an urgent need for internationally validated methods, which could serve as reference methods. To date, several methods have been submitted to validation trials at an international level; approaches now exist that can be used in different circumstances and for different food matrixes. Moreover, the requirement for the formal validation of methods is clearly accepted; several national and international bodies are active in organizing studies. Further validation studies, especially on the quantitative polymerase chain reaction methods, need to be performed to cover the rising demand for new extraction methods and other background matrixes, as well as for novel GMO constructs. PMID:12083280

  12. Conducting pilot and feasibility studies.

    PubMed

    Cope, Diane G

    2015-03-01

    Planning a well-designed research study can be tedious and laborious work. However, this process is critical and ultimately can produce valid, reliable study findings. Designing a large-scale randomized, controlled trial (RCT)-the gold standard in quantitative research-can be even more challenging. Even the most well-planned study potentially can result in issues with research procedures and design, such as recruitment, retention, or methodology. One strategy that may facilitate sound study design is the completion of a pilot or feasibility study prior to the initiation of a larger-scale trial. This article will discuss pilot and feasibility studies, their advantages and disadvantages, and implications for oncology nursing research. 
. PMID:25806886

  13. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 4 2011-07-01 2011-07-01 false Use of other validity studies. 1607.7 Section 1607.7 Labor Regulations Relating to Labor (Continued) EQUAL EMPLOYMENT OPPORTUNITY COMMISSION UNIFORM GUIDELINES ON EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 1607.7 Use of other validity studies. A. Validity studies not conducted by the...

  14. PSI-Center Validation Studies

    NASA Astrophysics Data System (ADS)

    Nelson, B. A.; Akcay, C.; Glasser, A. H.; Hansen, C. J.; Jarboe, T. R.; Marklin, G. J.; Milroy, R. D.; Morgan, K. D.; Norgaard, P. C.; Shumlak, U.; Sutherland, D. A.; Victor, B. S.; Sovinec, C. R.; O'Bryan, J. B.; Held, E. D.; Ji, J.-Y.; Lukin, V. S.

    2014-10-01

    The Plasma Science and Innovation Center (PSI-Center - http://www.psicenter.org) supports collaborating validation platform experiments with 3D extended MHD simulations using the NIMROD, HiFi, and PSI-TET codes. Collaborators include the Bellan Plasma Group (Caltech), CTH (Auburn U), HBT-EP (Columbia), HIT-SI (U Wash-UW), LTX (PPPL), MAST (Culham), Pegasus (U Wisc-Madison), SSX (Swarthmore College), TCSU (UW), and ZaP/ZaP-HD (UW). The PSI-Center is exploring application of validation metrics between experimental data and simulations results. Biorthogonal decomposition (BOD) is used to compare experiments with simulations. BOD separates data sets into spatial and temporal structures, giving greater weight to dominant structures. Several BOD metrics are being formulated with the goal of quantitive validation. Results from these simulation and validation studies, as well as an overview of the PSI-Center status will be presented.

  15. Bioconversion study conducted by JPL

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J.

    1978-01-01

    The Jet Propulsion Laboratory (JPL) of Caltech conducted a study of bioconversion as a means of identifying the role of biomass for meeting the national energy fuel and chemical requirements and the role and means for JPL-Caltech involvement in bioconversion. The bioconversion study included the following categories; biomass sources, chemicals from biomass, thermochemical conversion of biomass to fuels, biological conversion of biomass to fuels and chemicals, and basic bioconversion sciences. A detailed review is included of the bioconversion fields cited with specific conclusions and recommendations given for future research and development and overall biomass system engineering and economic studies.

  16. 49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false What is validity testing, and are laboratories... What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... of validity testing is to determine whether certain adulterants or foreign substances were added...

  17. 49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false What is validity testing, and are laboratories... What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... of validity testing is to determine whether certain adulterants or foreign substances were added...

  18. 49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false What is validity testing, and are laboratories... What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... of validity testing is to determine whether certain adulterants or foreign substances were added...

  19. 49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What is validity testing, and are laboratories... What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... of validity testing is to determine whether certain adulterants or foreign substances were added...

  20. 49 CFR 40.89 - What is validity testing, and are laboratories required to conduct it?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false What is validity testing, and are laboratories... What is validity testing, and are laboratories required to conduct it? (a) Specimen validity testing is... of validity testing is to determine whether certain adulterants or foreign substances were added...

  1. 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.

  2. Validation of a heat conduction model for finite domain, non-uniformly heated, laminate bodies

    NASA Astrophysics Data System (ADS)

    Desgrosseilliers, Louis; Kabbara, Moe; Groulx, Dominic; White, Mary Anne

    2015-08-01

    Infrared thermographic validation is shown for a closed-form analytical heat conduction model for non-uniformly heated, laminate bodies with an insulated domain boundary. Experiments were conducted by applying power to rectangular electric heaters and cooled by natural convection in air, but also apply to constant-temperature heat sources and forced convection. The model accurately represents two-dimensional laminate heat conduction behaviour giving rise to heat spreading using one-dimensional equations for the temperature distributions and heat transfer rates under steady-state and pseudo-steady-state conditions. Validation of the model with an insulated boundary (complementing previous studies with an infinite boundary) provides useful predictions of heat spreading performance and simplified temperature uniformity calculations (useful in log-mean temperature difference style heat exchanger calculations) for real laminate systems such as found in electronics heat sinks, multi-ply stovetop cookware and interface materials for supercooled salt hydrates. Computational determinations of implicit insulated boundary condition locations in measured data, required to assess model equation validation, were also demonstrated. Excellent goodness of fit was observed (both root-mean-square error and R 2 values), in all cases except when the uncertainty of low temperatures measured via infrared thermography hindered the statistical significance of the model fit. The experimental validation in all other cases supports use of the model equations in design calculations and heat exchange simulations.

  3. External validation of multivariable prediction models: a systematic review of methodological conduct and reporting

    PubMed Central

    2014-01-01

    Background Before considering whether to use a multivariable (diagnostic or prognostic) prediction model, it is essential that its performance be evaluated in data that were not used to develop the model (referred to as external validation). We critically appraised the methodological conduct and reporting of external validation studies of multivariable prediction models. Methods We conducted a systematic review of articles describing some form of external validation of one or more multivariable prediction models indexed in PubMed core clinical journals published in 2010. Study data were extracted in duplicate on design, sample size, handling of missing data, reference to the original study developing the prediction models and predictive performance measures. Results 11,826 articles were identified and 78 were included for full review, which described the evaluation of 120 prediction models. in participant data that were not used to develop the model. Thirty-three articles described both the development of a prediction model and an evaluation of its performance on a separate dataset, and 45 articles described only the evaluation of an existing published prediction model on another dataset. Fifty-seven percent of the prediction models were presented and evaluated as simplified scoring systems. Sixteen percent of articles failed to report the number of outcome events in the validation datasets. Fifty-four percent of studies made no explicit mention of missing data. Sixty-seven percent did not report evaluating model calibration whilst most studies evaluated model discrimination. It was often unclear whether the reported performance measures were for the full regression model or for the simplified models. Conclusions The vast majority of studies describing some form of external validation of a multivariable prediction model were poorly reported with key details frequently not presented. The validation studies were characterised by poor design, inappropriate handling and acknowledgement of missing data and one of the most key performance measures of prediction models i.e. calibration often omitted from the publication. It may therefore not be surprising that an overwhelming majority of developed prediction models are not used in practice, when there is a dearth of well-conducted and clearly reported (external validation) studies describing their performance on independent participant data. PMID:24645774

  4. 49 CFR 40.91 - What validity tests must laboratories conduct on primary specimens?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... certified laboratory would be useful in being able to report a positive or adulterated test result. ... validity tests must laboratories conduct on primary specimens? As a laboratory, when you conduct...

  5. 49 CFR 40.91 - What validity tests must laboratories conduct on primary specimens?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... certified laboratory would be useful in being able to report a positive or adulterated test result. ... validity tests must laboratories conduct on primary specimens? As a laboratory, when you conduct...

  6. VALIDATION OF A THERMAL CONDUCTIVITY MEASUREMENT SYSTEM FOR FUEL COMPACTS

    SciTech Connect

    Jeff Phillips; Colby Jensen; Changhu Xing; Heng Ban

    2011-03-01

    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.

  7. Predictive Validity of DSM-IV Oppositional Defiant and Conduct Disorders in Clinically Referred Preschoolers

    ERIC Educational Resources Information Center

    Keenan, Kate; Boeldt, Debra; Chen, Diane; Coyne, Claire; Donald, Radiah; Duax, Jeanne; Hart, Katherine; Perrott, Jennifer; Strickland, Jennifer; Danis, Barbara; Hill, Carri; Davis, Shante; Kampani, Smita; Humphries, Marisha

    2011-01-01

    Background: Diagnostic validity of oppositional defiant and conduct disorders (ODD and CD) for preschoolers has been questioned based on concerns regarding the ability to differentiate normative, transient disruptive behavior from clinical symptoms. Data on concurrent validity have accumulated, but predictive validity is limited. Predictive…

  8. CANFOR Portuguese version: validation study

    PubMed Central

    2013-01-01

    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. PMID:23721105

  9. FDDS: A Cross Validation Study.

    ERIC Educational Resources Information Center

    Sawyer, Judy Parsons

    The Family Drawing Depression Scale (FDDS) was created by Wright and McIntyre to provide a clear and reliable scoring method for the Kinetic Family Drawing as a procedure for detecting depression. A study was conducted to confirm the value of the FDDS as a systematic tool for interpreting family drawings with populations of depressed individuals.…

  10. Validation of CE modeling with a contactless conductivity array detector.

    PubMed

    Caslavska, Jitka; Koenka, Israel Joel; Hauser, Peter C; Thormann, Wolfgang

    2016-03-01

    Dynamic computer simulation data are compared for the first time with CE data obtained with a laboratory made system comprising an array of 8 contactless conductivity detectors (C(4) Ds). The experimental setup featured a 50 μm id linear polyacrylamide (LPA) coated fused-silica capillary of 70 cm length and a purpose built sequential injection analysis manifold for fluid handling of continuous or discontinuous buffer configurations and sample injection. The LPA coated capillary exhibits a low EOF and the manifold allows the placement of the first detector at about 2.7 cm from the sample inlet. Agreement of simulated electropherograms with experimental data was obtained for the migration and separation of cationic and anionic analyte and system zones in CZE configurations in which EOF and other column properties are constant. For configurations with discontinuous buffer systems, including ITP, experimental data obtained with the array detector revealed that the EOF is not constant. Comparison of simulation and experimental data of ITP systems provided the insight that the EOF can be estimated with an ionic strength dependent model similar to that previously used to describe EOF in fused-silica capillaries dynamically double coated with Polybrene and poly(vinylsulfonate). For the LPA coated capillaries, the electroosmotic mobility was determined to be 17-fold smaller compared to the case with the charged double coating. Simulation and array detection provide means for quickly investigating electrophoretic transport and separation properties. Without realistic input parameters, modeling alone is not providing data that match CE results. PMID:26799858

  11. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... seeking to obtain selection procedures from publishers and distributors should be careful to determine... selection procedure is valid; (2) Job similarity. The incumbents in the user's job and the incumbents in the job or group of jobs on which the validity study was conducted perform substantially the same...

  12. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... seeking to obtain selection procedures from publishers and distributors should be careful to determine... selection procedure is valid; (2) Job similarity. The incumbents in the user's job and the incumbents in the job or group of jobs on which the validity study was conducted perform substantially the same...

  13. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... seeking to obtain selection procedures from publishers and distributors should be careful to determine... selection procedure is valid; (2) Job similarity. The incumbents in the user's job and the incumbents in the job or group of jobs on which the validity study was conducted perform substantially the same...

  14. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... seeking to obtain selection procedures from publishers and distributors should be careful to determine... selection procedure is valid; (2) Job similarity. The incumbents in the user's job and the incumbents in the job or group of jobs on which the validity study was conducted perform substantially the same...

  15. 49 CFR 40.91 - What validity tests must laboratories conduct on primary specimens?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false What validity tests must laboratories conduct on primary specimens? 40.91 Section 40.91 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Drug Testing Laboratories § 40.91 What validity tests must laboratories...

  16. Conducting a wind sensing study

    NASA Technical Reports Server (NTRS)

    Byer, R. L.

    1985-01-01

    Signal-to-noise requirements, and how signal-to-noise determines wind velocity measurement accuracy were studied. A Nd:YAG-based system was found to be competitive with a CO2-based system. Hardware was developed for a coherent Nd:YAG LIDAR system, and is being integrated into a functioning system. A diode-pumped monolithic rod laser to be used as a reference oscillator, a high-power, single-mode ring laser, for use as a master oscillator, and a high-gain, multipass amplifier were constructed.

  17. Vitamin D Dietary Intake Questionnaire Validation Conducted among Young Polish Women

    PubMed Central

    Głąbska, Dominika; Guzek, Dominika; Sidor, Patrycja; Włodarek, Dariusz

    2016-01-01

    Due to inadequate intake of Vitamin D, identification of individuals characterised by the highest risk of deficiencies is one of the more crucial tasks for public health. The aim of the presented study was to assess the validity and reproducibility of the designed Vitamin D dietary intake questionnaire based on food frequency assessment—VIDEO-FFQ (VItamin D Estimation Only—Food Frequency Questionnaire) in a group of Polish women aged 20–30 years. Seventy-five participants kept a three-day dietary record and filled out the VIDEO-FFQ twice (immediately after the three-day dietary record and after six weeks). The assessment of validity and reproducibility was conducted by verifying standard errors of estimation, median differences, and percentages of individuals classified into tertiles, correlations and Bland-Altman plots. The Vitamin D intake for the majority of the surveyed women was inadequate as over 85% of them were characterised by values of intake lower than 5.0 μg per day. The results allowed concluding that a high accuracy of the VIDEO-FFQ was achieved. The required Bland-Altman index values lower than 5.0% were obtained, confirming satisfactory validity and reproducibility. The VIDEO-FFQ may be deemed a convenient practical tool for the estimation of Vitamin D intake in young women. PMID:26742070

  18. Thinking and Creative Styles: A Validity Study

    ERIC Educational Resources Information Center

    Wechsler, Solange Muglia; Vendramini, Claudette Maria Medeiros; Oakland, Thomas

    2012-01-01

    The validity evidences of thinking and creative styles were analyzed. Two studies are reported, one analyzing the dimensionality of creative styles and the other verifying their external validity. Participants were Brazilians, 1,752 in the first study (55% women) and 128 in the second study (53% women), among whom 45% had demonstrated creative…

  19. Test of Creative Imagination: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Gundogan, Aysun; Ari, Meziyet; Gonen, Mubeccel

    2013-01-01

    The purpose of this study was to investigate validity and reliability of the test of creative imagination. This study was conducted with the participation of 1000 children, aged between 9-14 and were studying in six primary schools in the city center of Denizli Province, chosen by cluster ratio sampling. In the study, it was revealed that the…

  20. Validation of the SSRS-T, Preschool Level as a Measure of Positive Social Behavior and Conduct Problems

    ERIC Educational Resources Information Center

    Rich, Erika Carpenter; Shepherd, Elizabeth J.; Nangle, Douglas W.

    2008-01-01

    Evidence for the validity of the Social Skills Rating System for Teachers, Preschool Level (SSRS-T) as a measure of positive social skills and conduct problems was examined in a sample of Head Start preschoolers. One feature of the study was the comparative analysis of the original published factor structure of the Social Skills Scale (i.e.,…

  1. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA

    EPA Science Inventory

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

  2. Fracture conductivity studies: Project OEIC. Final report

    SciTech Connect

    Maloney, D.R.

    1985-11-01

    The objectives of this study were to develop facilities and obtain engineering data for predicting the flow conductivity of hydraulically generated fractures, in oil and gas producing underground formations, from reservoir rock and proppant properties. Equipment and methods used to predict the embedment of single and multilayer proppant placements into the faces of a hydraulic fracture are presented. Proppant conductivity test equipment, engineering data, and procedures based on proposed API recommendations are described. These procedures were used to predict the flow conductivity of propped fractures. Factors which effect the conductivity of propped fractures are discussed. 16 refs., 16 figs., 1 tab.

  3. FETAX interlaboratory validation study: Phase 2 testing

    SciTech Connect

    Bantle, J.A. . Dept. of Zoology); Burton, D.T. ); Dawson, D.A. . Dept. of Biology and Toxicology)

    1994-10-01

    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.

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

    ERIC Educational Resources Information Center

    Clay, Rex J.

    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 colleges

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

    ERIC Educational Resources Information Center

    Clay, Rex J.

    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 colleges…

  6. Gas release and conductivity modification studies

    NASA Technical Reports Server (NTRS)

    Linson, L. M.; Baxter, D. C.

    1979-01-01

    The behavior of gas clouds produced by releases from orbital velocity in either a point release or venting mode is described by the modification of snowplow equations valid in an intermediate altitude regime. Quantitative estimates are produced for the time dependence of the radius of the cloud, the average internal energy, the translational velocity, and the distance traveled. The dependence of these quantities on the assumed density profile, the internal energy of the gas, and the ratio of specific heats is examined. The new feature is the inclusion of the effect of the large orbital velocity. The resulting gas cloud models are used to calculate the characteristics of the field line integrated Pedersen conductivity enhancements that would be produced by the release of barium thermite at orbital velocity in either the point release or venting modes as a function of release altitude and chemical payload weight.

  7. Code Validation Study for Base Flows

    NASA Technical Reports Server (NTRS)

    Ascoli, Edward P.; Heiba, Adel H.; Lagnado, Ronald R.; Ungewitter, Ronald J.; Williams, Morgan

    1993-01-01

    New and old rocket launch concepts recommend the clustering of motors for improved lift capability. The flowfield of the base region of the rocket is very complex and can contain high temperature plume gases. These hot gases can cause catastrophic problems if not adequately designed for. To assess the base region characteristics, advanced computational fluid dynamics (CFD) is being used. As a precursor to these calculations the CFD code requires validation on base flows. The primary objective of this code validation study was to establish a high level of confidence in predicting base flows with the USA CFD code. USA has been extensively validated for fundamental flows and other applications. However, base heating flows have a number of unique characteristics so it was necessary to extend the existing validation for this class of problems. In preparation for the planned NLS 1.5 Stage base heating analysis, six case sets were studied to extend the USA code validation data base. This presentation gives a cursive review of three of these cases. The cases presented include a 2D axi-symmetric study, a 3D real nozzle study, and a 3D multi-species study. The results of all the studies show good general agreement with data with no adjustments to the base numerical algorithms or physical models in the code. The study proved the capability of the USA code for modeling base flows within the accuracy of available data.

  8. Proton Conductivity Studies on Biopolymer Electrolytes

    SciTech Connect

    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.

    2010-07-07

    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.

  9. Predicting Children's Academic Achievement from Early Assessment Scores: A Validity Generalization Study

    ERIC Educational Resources Information Center

    Kim, Juhu; Suen, Hoi K.

    2003-01-01

    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…

  10. 29 CFR 1607.5 - General standards for validity studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... validity. Evidence of the validity of a test or other selection procedure by a criterion-related validity... validity of a test or other selection procedure by a content validity study should consist of data showing... test or other selection procedure through a construct validity study should consist of data...

  11. 29 CFR 1607.5 - General standards for validity studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... validity. Evidence of the validity of a test or other selection procedure by a criterion-related validity... validity of a test or other selection procedure by a content validity study should consist of data showing... test or other selection procedure through a construct validity study should consist of data...

  12. 29 CFR 1607.5 - General standards for validity studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... validity. Evidence of the validity of a test or other selection procedure by a criterion-related validity... validity of a test or other selection procedure by a content validity study should consist of data showing... test or other selection procedure through a construct validity study should consist of data...

  13. 29 CFR 1607.5 - General standards for validity studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... validity. Evidence of the validity of a test or other selection procedure by a criterion-related validity... validity of a test or other selection procedure by a content validity study should consist of data showing... test or other selection procedure through a construct validity study should consist of data...

  14. CORD Conducts a Feasibility Study. Final Report.

    ERIC Educational Resources Information Center

    Best, Gilmary

    This document presents the results of a feasibility study conducted by the Consortium for Development of Research Potential in Education (CORD) to determine if the 5 institutions in the Detroit area that comprise CORD can pool their resources to provide a coordinated institute for re-educating the conventionally trained teachers in multicultural…

  15. Framework for planning and conducting pilot studies.

    PubMed

    Smith, Lisa Janette; Harrison, Margaret B

    2009-12-01

    Researchers working with partners in home care to plan a pragmatic multicenter community-based, randomized, controlled trial for leg ulcer compression treatment realized a smaller pilot study would be necessary. Because no framework for conducting pilot studies could be found, the authors developed a framework for pilot study methodology to inform the planning of such research. To this end, an integrative literature review was conducted, guided by an explicit search strategy, retrieval procedures, and appraisal process, to identify recognized pilot study aims, processes, and methodologies used in previously reported community pilot studies. Factors influencing study inclusion were recognized pilot study aims and purposes and a concise working definition of pilot study. Methodologies used in previously conducted community pilot studies were reviewed. Although relevant published research was limited, 11 pilot studies met the inclusion criteria for this review and contained suggestions to further develop or improve plans for larger definitive trials to enable a better fit of protocols within the delivery systems and scopes of practice. Pilot research processes could be divided into two stages: early planning and pilot trial. Direction for procedures and methods was gained relative to planning for an effective pilot study regarding eligibility, recruitment and data collection, management, and analysis. The results were used to develop an organizing framework for the authors' pilot study and named the Pilot Research Process (PReP) Framework. The process was instrumental in working with the authors' research team and clinical partners in the planning of their leg ulcer treatment pilot study. This framework may provide a foundation for others to analyze or develop a pilot study methodology in planning a large-scale study. PMID:20038790

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

    PubMed

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

    2002-02-01

    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

  17. Sentence Completion Form: A Validation Study

    ERIC Educational Resources Information Center

    Soh, K. C.

    1973-01-01

    In addition to the correlations with scholastic achievement as evidence of validity reported by Feldhusen and his associates, the results reported in this study provide evidence which suggests that the Sentence Completion Form is an efficient measurement of general adjustment of school children. (Author)

  18. A scattering model for perfectly conducting random surfaces. I - Model development. II - Range of validity

    NASA Technical Reports Server (NTRS)

    Fung, A. K.; Pan, G. W.

    1987-01-01

    The surface current on a perfectly conducting randomly rough surface is estimated by solving iteratively a standard integral equation, and the estimate is then used to compute the far-zone scattered fields and the backscattering coefficients for vertical, horizontal and cross polarizations. The model developed here yields a simple backscattering coefficient expression in terms of the surface parameters. The expression reduces analytically to the Kirchhoff and the first-order small-perturbation model in the high- and low-frequency regions, respectively. The range of validity of the model is determined.

  19. Two phase detonation studies conducted in 1971

    NASA Technical Reports Server (NTRS)

    Nicholls, J. A.

    1972-01-01

    A report is presented describing the research conducted on five phases: (1) ignition of fuel drops by a shock wave and passage of a shock wave over a burning drop, (2) the energy release pattern of a two-phase detonation with controlled drop sizes, (3) the attenuation of shock and detonation waves passing over an acoustic liner, (4) experimental and theoretical studies of film detonations, and (5) a simplified analytical model of a rotating two-phase detonation wave in a rocket motor.

  20. CFD Validation Studies for Hypersonic Flow Prediction

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.

    2001-01-01

    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 serves as a focus for a code validation session but are not available to the authors until the conclusion of this session. The first set of experiments considered here involve Mach 9.5 and Mach 11.3 N2 flow over a hollow cylinder-flare with 30 degree flare angle at several Reynolds numbers sustaining laminar, separated flow. Truncated and extended flare configurations are considered. The second set of experiments, at similar conditions, involves flow over a sharp, double cone with fore-cone angle of 25 degrees and aft-cone angle of 55 degrees. Both sets of experiments involve 30 degree compressions. Location of the separation point in the numerical simulation is extremely sensitive to the level of grid refinement in the numerical predictions. The numerical simulations also show a significant influence of Reynolds number on extent of separation. Flow unsteadiness was easily introduced into the double cone simulations using aggressive relaxation parameters that normally promote convergence.

  1. CFD Validation Studies for Hypersonic Flow Prediction

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.

    2001-01-01

    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 serves as a focus for a code validation session but are not available to the authors until the conclusion of this session. The first set of experiments considered here involve Mach 9.5 and Mach 11.3 N, flow over a hollow cylinder-flare with 30 deg flare angle at several Reynolds numbers sustaining laminar, separated flow. Truncated and extended flare configurations are considered. The second set of experiments, at similar conditions, involves flow over a sharp, double cone with fore-cone angle of 25 deg and aft-cone angle of 55 deg. Both sets of experiments involve 30 deg compressions. Location of the separation point in the numerical simulation is extremely sensitive to the level of grid refinement in the numerical predictions. The numerical simulations also show a significant influence of Reynolds number on extent of separation. Flow unsteadiness was easily introduced into the double cone simulations using aggressive relaxation parameters that normally promote convergence.

  2. Development and validation of an unsupervised scoring system (Autonomate) for skin conductance response analysis

    PubMed Central

    Green, Steven R.; Kragel, Philip A.; Fecteau, Matthew E.; LaBar, Kevin S.

    2014-01-01

    The skin conductance response (SCR) is increasingly being used as a measure of sympathetic activation concurrent with neuroscience measurements. We present a method of automated analysis of SCR data in the contexts of event-related cognitive tasks and nonspecific responding to complex stimuli. The primary goal of the method is to accurately measure the classical trough-to-peak amplitude of SCR in a fashion closely matching manual scoring. To validate the effectiveness of the method in event-related paradigms, three archived datasets were analyzed by two manual raters, the fully-automated method (Autonomate), and three alternative software packages. Further, the ability of the method to score non-specific responses to complex stimuli was validated against manual scoring. Results indicate high concordance between fully-automated and computer-assisted manual scoring methods. Given that manual scoring is error prone, subject to bias, and time consuming, the automated method may increase efficiency and accuracy of SCR data analysis. PMID:24184342

  3. NASA's Rodent Research Project: Validation of Capabilities for Conducting Long Duration Experiments in Space

    NASA Technical Reports Server (NTRS)

    Choi, Sungshin Y.; Cole, Nicolas; Reyes, America; Lai, San-Huei; Klotz, Rebecca; Beegle, Janet E.; Wigley, Cecilia L.; Pletcher, David; Globus, Ruth K.

    2015-01-01

    Research using rodents is an essential tool for advancing biomedical research on Earth and in space. Prior rodent experiments on the Shuttle were limited by the short flight duration. The International Space Station (ISS) provides a new platform for conducting rodent experiments under long duration conditions. Rodent Research (RR)-1 was conducted to validate flight hardware, operations, and science capabilities that were developed at the NASA Ames Research Center. Twenty C57BL6J adult female mice were launched on Sept 21, 2014 in a Dragon Capsule (SpaceX-4), then transferred to the ISS for a total time of 21-22 days (10 commercial mice) or 37 days (10 validation mice). Tissues collected on-orbit were either rapidly frozen or preserved in RNAlater at -80C (n2group) until their return to Earth. Remaining carcasses on-orbit were rapidly frozen for dissection post-flight. The three controls groups at Kennedy Space Center consisted of: Basal mice euthanized at the time of launch, Vivarium controls housed in standard cages, and Ground Controls (GC) housed in flight hardware within an environmental chamber. Upon return to Earth, there were no differences in body weights between Flight (FLT) and GC at the end of the 37 days in space. Liver enzyme activity levels of FLT mice and all control mice were similar in magnitude to those of the samples that were processed under optimal conditions in the laboratory. Liver samples dissected on-orbit yielded high quality RNA (RIN8.99+-0.59, n7). Liver samples dissected post-flight from the intact, frozen FLT carcasses yielded RIN of 7.27 +- 0.52 (n6). Additionally, wet weights of various tissues were measured. Adrenal glands and spleen showed no significant differences in FLT compared to GC although thymus and livers weights were significantly greater in FLT compared to GC. Over 3,000 tissue aliquots collected post-flight from the four groups of mice were deposited into the Ames Life Science Data Archives for future Biospecimen Sharing Program. Together, the RR validation flight successfully demonstrates the capability to support long-duration experimentation on the ISS to achieve both basic science and biomedical objectives.

  4. Conducting a multi family member interview study.

    PubMed

    Reczek, Corinne

    2014-06-01

    Family researchers have long recognized the utility of incorporating interview data from multiple family members. Yet, relatively few contemporary scholars utilize such an approach due to methodological underdevelopment. This article contributes to family scholarship by providing a roadmap for developing and executing in-depth interview studies that include more than one family member. Specifically, it outlines the epistemological frames that most commonly underlie this approach, illustrates thematic research questions that it best addresses, and critically reviews the best methodological practices of conducting research with this approach. The three most common approaches are addressed in depth: separate interviews with each family member, dyadic or group interviews with multiple family members, and a combined approach that uses separate and dyadic or group interviews. This article speaks to family scholars who are at the beginning stages of their research project but are unsure of the best qualitative approach to answer a given research question. PMID:24410452

  5. Turkish Adaptation of the Mentorship Effectiveness Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Yirci, Ramazan; Karakose, Turgut; Uygun, Harun; Ozdemir, Tuncay Yavuz

    2016-01-01

    The purpose of this study is to adapt the Mentoring Relationship Effectiveness Scale to Turkish, and to conduct validity and reliability tests regarding the scale. The study group consisted of 156 university science students receiving graduate education. Construct validity and factor structure of the scale was analyzed first through exploratory…

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

    ERIC Educational Resources Information Center

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

    2012-01-01

    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

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

    ERIC Educational Resources Information Center

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

    2012-01-01

    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…

  8. Neuroscience Investigations: An Overview of Studies Conducted

    NASA Technical Reports Server (NTRS)

    Reschke, Millard F.

    1999-01-01

    The neural processes that mediate human spatial orientation and adaptive changes occurring in response to the sensory rearrangement encountered during orbital flight are primarily studied through second and third order responses. In the Extended Duration Orbiter Medical Project (EDOMP) neuroscience investigations, the following were measured: (1) eye movements during acquisition of either static or moving visual targets, (2) postural and locomotor responses provoked by unexpected movement of the support surface, changes in the interaction of visual, proprioceptive, and vestibular information, changes in the major postural muscles via descending pathways, or changes in locomotor pathways, and (3) verbal reports of perceived self-orientation and self-motion which enhance and complement conclusions drawn from the analysis of oculomotor, postural, and locomotor responses. In spaceflight operations, spatial orientation can be defined as situational awareness, where crew member perception of attitude, position, or motion of the spacecraft or other objects in three-dimensional space, including orientation of one's own body, is congruent with actual physical events. Perception of spatial orientation is determined by integrating information from several sensory modalities. This involves higher levels of processing within the central nervous system that control eye movements, locomotion, and stable posture. Spaceflight operational problems occur when responses to the incorrectly perceived spatial orientation are compensatory in nature. Neuroscience investigations were conducted in conjunction with U. S. Space Shuttle flights to evaluate possible changes in the ability of an astronaut to land the Shuttle or effectively perform an emergency post-landing egress following microgravity adaptation during space flights of variable length. While the results of various sensory motor and spatial orientation tests could have an impact on future space flights, our knowledge of sensorimotor adaptation to spaceflight is limited, and the future application of effective countermeasures depends, in large part, on the results from appropriate neuroscience investigations. Therefore, the objective of the neuroscience investigations could have a negative effect on mission success. The Neuroscience Laboratory, Johnson Space Center (JSC), implemented three integrated Detailed Supplementary Objectives (DSO) designed to investigate spatial orientation and the associated compensatory responses as a part of the EDOMP. The four primary goals were (1) to establish a normative database of vestibular and associated sensory changes in response to spaceflight, (2) to determine the underlying etiology of neurovestibular and sensory motor changes associated with exposure to microgravity and the subsequent return to Earth, (3) to provide immediate feedback to spaceflight crews regarding potential countermeasures that could improve performance and safety during and after flight, and (4) to take under consideration appropriate designs for preflight, in-flight, and postflight countermeasures that could be implemented for future flights.

  9. 40 CFR 761.395 - A validation study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false A validation study. 761.395 Section...)(4) § 761.395 A validation study. (a) Decontaminate the following prepared sample surfaces using the... must be 10 µg/100 cm2, then the validation study failed and the solvent may not be used...

  10. 40 CFR 761.395 - A validation study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROHIBITIONS Comparison Study for Validating a New Performance-Based Decontamination Solvent Under § 761.79(d)(4) § 761.395 A validation study. (a) Decontaminate the following prepared sample surfaces using the... 40 Protection of Environment 31 2011-07-01 2011-07-01 false A validation study. 761.395...

  11. Thermal and electrical contact conductance studies

    NASA Technical Reports Server (NTRS)

    Vansciver, S. W.; Nilles, M.

    1985-01-01

    Prediction of electrical and thermal contact resistance for pressed, nominally flat contacts is complicated by the large number of variables which influence contact formation. This is reflected in experimental results as a wide variation in contact resistances, spanning up to six orders of magnitude. A series of experiments were performed to observe the effects of oxidation and surface roughness on contact resistance. Electrical contact resistance and thermal contact conductance from 4 to 290 K on OFHC Cu contacts are reported. Electrical contact resistance was measured with a 4-wire DC technique. Thermal contact conductance was determined by steady-state longitudinal heat flow. Corrections for the bulk contribution ot the overall measured resistance were made, with the remaining resistance due solely to the presence of the contact.

  12. Electrochemical corrosion studies in low conductivity propellants

    NASA Technical Reports Server (NTRS)

    Blue, G. D.; Moran, C. M.; Distefano, S.

    1986-01-01

    The Jet Propulsion Laboratory is investigating the possibility of developing advanced electrochemical techniques as accelerated compatibility tests for metal/propellant systems which overcome the problems associated with the low conductivity of the liquid propellants (e.g., hydrazines, nitrogen tetroxide). Both DC techniques and AC electrochemical impedance spectroscopy are being evaluated. Progress has been made in experiments involving stainless steel with hydrazine and nitrogen tetroxide propellants.

  13. A Cross-Validation Study of Police Recruit Performance as Predicted by the IPI and MMPI.

    ERIC Educational Resources Information Center

    Shusman, Elizabeth J.; And Others

    Validation and cross-validation studies were conducted using the Minnesota Multiphasic Personality Inventory (MMPI) and Inwald Personality Inventory (IPI) to predict job performance for 698 urban male police officers who completed a six-month training academy. Job performance criteria evaluated included absence, lateness, derelictions, negative…

  14. A study of conducting polymer morphology

    NASA Astrophysics Data System (ADS)

    Warren, L. F.; Walker, J. A.; Anderson, D. P.; Rhodes, C. G.; Buckley, L. J.

    1989-08-01

    A series of freestanding conducting polypyrrole and poly-three-methylthiophene films was prepared and examined by X-ray diffraction and transmission electron microscopy (TEM). The degree of order observed in polypyrroles was highly dependent upon the incorporated 'dopant' anions and also on deposition conditions. Examination of a large variety of dopant systems showed that substituted benzenesulfonate and long aliphatic chain monoanions imparted the highest order, and chemically prepared polypyrroles were less ordered than their electrochemical counterparts. Doped poly-three-methylthiophene exhibited comparable order, yet was less flexible in its ability to incorporate large dopant anions. Crystalline phases were detected by electron diffraction in some polymer systems.

  15. Exemplary Practice in Work-Based Education: A Validation Study

    ERIC Educational Resources Information Center

    Zanibbi, Mike; Munby, Hugh; Hutchinson, Nancy L.; Versnel, Joan; Chin, Peter

    2006-01-01

    This paper validates the concept of exemplary practice in work-based education (WBE) programs. The validation uses two theoretical frameworks: Social Cognitive Career Theory, and Billett's research on workplace learning. The empirical component of the validation study consists of two widely differing case studies of high school students in work…

  16. [Validation study of the Depressive Experience Questionnaire].

    PubMed

    Atger, F; Frasson, G; Loas, G; Guibourgé, S; Corcos, M; Perez Diaz, F; Speranza, M; Venisse, J-L; Lang, F; Stephan, Ph; Bizouard, P; Flament, M; Jeammet, Ph

    2003-01-01

    Sidney Blatt, considering as being insufficient the categorical-symptomatic approach of depression, has worked out a theory of depression and psychopathology that integrates the contributions of psychoanalysis as well as cognitive and developmental psychology. Within a broad psychoanalytic framework, Blatt's formulation focus on the quality of interpersonal relationship, the nature of object representation and early life experiences. Personality development is viewed as the consequence of the interaction of 2 basic developmental tasks: the establishment of the capacity to form stable, enduring, mutually satisfying interpersonal relationships and the achievement of a differentiated, realistic, essentially positive identity. The relationship between these 2 developmental lines involves a complex dialectical process during which progress in each line is essential for progress in the other and which contributes to the development of both a sense of identity and the capacity for interpersonal relatedness. These developmental lines permit not only to define an during individual's primary personality configuration but also enable to identify cognitive structures that are inherent in various forms of psychopathology, including depression. Disruptions at different developmental stages create vulnerability to different subsequent psychological disturbances. Blatt characterised as anaclitic or dependent the axis concerned with interpersonal relationship and as introjective or self-critical the axis concerned with development of the sense of self and identity. Depressive Experience Questionnaire was developed by Blatt et al. to determine the validity of this model of psychopathology which emphazises continuities between normal and pathological forms of depression. The instrument was developed by Blatt et al. by assembling a pool of items describing experiences frequently reported by depressed individual. Sixty-six items were selected and administered to a large nonclinical sample (500 female and 160 male undergraduates). Principal component analysis within sex performed on the answers to DEQ confirmed his assumption in identifying two principal depressive dimensions. The first factor involved items that are primarily externally directed and refer to a disturbance of interpersonal relationships (anaclitism); the second factor consists of items that are more internally directed and reflect concerns about self-identity (self-criticism). A third factor emerged, assessing the good functioning of subject and confidence in his resources and capacities (efficacy). Scales derived from these factors have high internal consistency and substantial test-retest reliability. The solutions for men and women were highly congruent. Factor structure has been replicated in several nonclinical and clinical samples, supporting considerable evidence to the construct validity of the DEQ Dependency and Self-criticism scales. An adolescent form of DEQ (DEQ-A) has successively been developed. Factor analysis revealed three factors that were highly congruent in female and male students and with the three factors of the original DEQ. The reliability, internal consistency and validity of DEQ-A indicate that the DEQ-A closely parallels the DEQ, especially in the articulation of Dependency and Self-criticism as two factors in depression. These formulations and clinical observations about the importance of differentiating a depression focused on issues of self-criticism from issues of dependency are consistent with the formulations of others theorists which, from very different theoretical perspectives, posit 2 types of depression, one in which either perceived loss or rejection in social relationships is central and the other in which perceived failure in achievement, guilt or lack of control serves as the precipitant of depression. These 2 types of experiences have been characterized as dominant other and dominant goal , as anxiously attached and compulsively self-reliant and as sociotropic and autonomous . Our work presents the results of a validation study of both forms of Blatt's questionnaire (for adults--DEQ--and for adolescents--DEQA) translated in French in a large population of normal subjects, aged 15 to 45 years. DEQ and DEQ-A were compared by inspection of items loading strongly on each factor and by correlation of the three factors of adults and adolescents. The exploratory factor analysis of DEQ and DEQA revealed three orthogonal factors, corresponding with Blatt's original dimensions. Consistency and external validity were adequate for all 3 factors of DEQ and DEQ-A. Anaclitism and self-criticism dimensions of DEQ and DEQ-A correlate positively with measures of depression (DSM-IV, Beck Depression Inventory), consistently with the results obtained by Blatt. Differently from this author, anaclitism appears to be less differentiated in males than in females, suggesting that the concept of dependence could assume different relevance for men and women. PMID:14615694

  17. Practical challenges in conducting respiratory studies

    PubMed Central

    Hake, Sanjay D.; Patil, Mahesh L.; Shah, Tapankumar M.; Gokhale, Partha M.; Suvarna, Viraj

    2015-01-01

    Respiratory studies are complex on account of specific therapeutic knowledge that is needed and various instruments that are used for the management of this condition. Monitoring a respiratory study requires knowledge of the specific disease and associated guidelines. The intent of this article is to help clinical research professionals understand the technicalities, challenges, and the nuances of performing respiratory studies. PMID:25657898

  18. Conceptualizing and Validating Marital Quality in Beijing: A Pilot Study.

    PubMed

    Zhang, Huiping; Xu, Xiaohe; Tsang, Sandra K M

    2013-08-01

    Since the inception of the economic reform, marital relationship in urban China has undergone dramatic transformations. Though the burgeoning body of scholarly research has demonstrated that marital quality has increasingly become an important aspect of family life among married persons in urban China, both the conceptualization and measurement of marital quality remain underdeveloped. The purpose of this pilot study is to develop and validate a comprehensive and culturally appropriate marital quality scale, namely the Chinese Marital Quality Scale (CMQS). Results from the confirmatory factor analysis (CFA) conducted on a sample of 387 married persons from Beijing indicate that the CMQS can be conceptualized as a two-factorial and multidimensional construct, encompassing marital happiness, marital interaction, marital disagreement, marital problem, and marital instability. Additional statistical analyses also indicate that the CMQS has exhibited satisfactory reliability and concurrent validity. It is thus concluded that the CMQS is a reliable and valid instrument to measure marital quality in contemporary Beijing and possibly in other Chinese cities. PMID:23874055

  19. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date...

  20. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study,...

  1. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date...

  2. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date...

  3. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date...

  4. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date...

  5. Expert system verification and validation study

    NASA Technical Reports Server (NTRS)

    French, Scott W.; Hamilton, David

    1992-01-01

    Five workshops on verification and validation (V&V) of expert systems (ES) where taught during this recent period of performance. Two key activities, previously performed under this contract, supported these recent workshops (1) Survey of state-of-the-practice of V&V of ES and (2) Development of workshop material and first class. The first activity involved performing an extensive survey of ES developers in order to answer several questions regarding the state-of-the-practice in V&V of ES. These questions related to the amount and type of V&V done and the successfulness of this V&V. The next key activity involved developing an intensive hands-on workshop in V&V of ES. This activity involved surveying a large number of V&V techniques, conventional as well as ES specific ones. In addition to explaining the techniques, we showed how each technique could be applied on a sample problem. References were included in the workshop material, and cross referenced to techniques, so that students would know where to go to find additional information about each technique. In addition to teaching specific techniques, we included an extensive amount of material on V&V concepts and how to develop a V&V plan for an ES project. We felt this material was necessary so that developers would be prepared to develop an orderly and structured approach to V&V. That is, they would have a process that supported the use of the specific techniques. Finally, to provide hands-on experience, we developed a set of case study exercises. These exercises were to provide an opportunity for the students to apply all the material (concepts, techniques, and planning material) to a realistic problem.

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

    NASA Astrophysics Data System (ADS)

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

    2005-12-01

    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) are fully known and errors and biases are minimal. In the field, pumping tests are more prone to variations in forcing functions and errors and biases can never be fully quantified. The main objective of this paper is to examine the accuracy of the hydraulic conductivity tomograms obtained from steady-state hydraulic tomography. We conduct hydraulic tests at multiple scales in a laboratory aquifer with deterministic heterogeneity to generate various validation data. To validate the tomograms, we compare the conditional mean and variance of hydraulic conductivity from the inverse model to the sample mean and variance of results from other measurements. Measurements include multiple hydraulic conductivity estimates from core, slug, single-hole and cross-hole tests as well as several steady-state flow-through experiments obtained within the sandbox. We also examine the influence of errors and biases on inversion results using forward and inverse simulations of synthetic and real cross-hole hydraulic tests. The role of signal-to-noise ratio, order of test data sequentially included in inverse modeling, the number of observation intervals, and conditioning with different data sets are discussed in the context of improving the quality of hydraulic conductivity tomograms.

  7. An Agenda for NAEP Validity Research: NAEP Validity Studies. Working Paper Series.

    ERIC Educational Resources Information Center

    Stancavage, Frances B.

    The National Assessment of Educational Progress (NAEP) Validity Studies Panel undertook a systematic analysis to consider the domain of validity threats to NAEP and to identify the most urgent research priorities. A framework of six broad categories was developed: (1) the constructs measured within each of NAEP's subject domains; (2) the manner in…

  8. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test...

  9. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test...

  10. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test...

  11. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test...

  12. SAMICS Validation. SAMICS Support Study, Phase 3

    NASA Technical Reports Server (NTRS)

    1979-01-01

    SAMICS provides a consistent basis for estimating array costs and compares production technology costs. A review and a validation of the SAMICS model are reported. The review had the following purposes: (1) to test the computational validity of the computer model by comparison with preliminary hand calculations based on conventional cost estimating techniques; (2) to review and improve the accuracy of the cost relationships being used by the model: and (3) to provide an independent verification to users of the model's value in decision making for allocation of research and developement funds and for investment in manufacturing capacity. It is concluded that the SAMICS model is a flexible, accurate, and useful tool for managerial decision making.

  13. Construct Validation Theory Applied to the Study of Personality Dysfunction

    PubMed Central

    Zapolski, Tamika C. B.; Guller, Leila; Smith, Gregory T.

    2013-01-01

    The authors review theory validation and construct validation principles as related to the study of personality dysfunction. Historically, personality disorders have been understood to be syndromes of heterogeneous symptoms. The authors argue that the syndrome approach to description results in diagnoses of unclear meaning and constrained validity. The alternative approach of describing personality dysfunction in terms of homogeneous dimensions of functioning avoids the problems of the syndromal approach and has been shown to provide more valid description and diagnosis. The authors further argue that description based on homogeneous dimensions of personality function/dysfunction is more useful, because it provides direct connections to validated treatments. PMID:22321263

  14. Electrophysiological validation of total atrial conduction time measurement by tissue doppler echocardiography according to age and sex in healthy adults

    PubMed Central

    Erdem, Fatma Hizal; Erdem, Alim; Özlü, Fatih; Ozturk, Serkan; Ayhan, Suzi Selim; Çağlar, Sabri Onur; Yazici, Mehmet

    2015-01-01

    Background We sought to validate total atrial conduction time (TACT) measurement via tissue Doppler imaging (TDI) by comparing the electrophysiological study (EPS) measurements of healthy subjects, according to age and sex. Methods Eighty patients with normal EPS results were included. TACT was measured by EPS and TDI. For validation, the results of TDI were compared with those of EPS. TACT was assessed by measuring the time interval between the beginning of the P-wave on the surface ECG, and the peak A-wave on TDI from the left atrial lateral wall, just over the mitral annulus. Electrophysiological TACT was defined as the time from the high right atrial electrogram to the distal coronary sinus atrial electrogram around the left lateral portion of the mitral ring. Results EPS and TDI measurements of the TACT were significantly and positively correlated among men and women in 20–30 years (p=0.008, r=0.412; p>0.001, r=0.706, respectively), and those in the 30–40 years group (p=0.001, r=0.649; p=0.001, r=0.696). In contrast, EPS and TDI measurements of TACT were not significantly different among men and women in the 20–30 years and those in the 30–40 years group (p>0.05, for both). On univariate regression analyses, TACT was independently associated with age (β=0.342, =0.001). Conclusions When assessed according to the age and sex of healthy participants, TDI and EPS measurements during TACT assessments were similar and correlated with each other. The measurement of TACT via TDI may be used accurately and confidently than the measurement via EPS in healthy individuals.

  15. A validation study of homeopathic prescribing and patient care indicators.

    PubMed

    Koley, Munmun; Saha, Subhranil; Ghosh, Shubhamoy; Nag, Goutam; Kundu, Monojit; Mondal, Ramkumar; Purkait, Rajib; Patra, Supratim

    2014-10-01

    A preliminary version of the homeopathic prescribing and patient care indicators was available. The instrument was modified further in this study with an intention to address formally its validity and reliability, audit prescriptions, identify areas of sub-optimal prescribing, and highlight target areas for improving the quality of practices. A cross-sectional study with record analysis was conducted on systematically sampled 377 patients of Mahesh Bhattacharyya Homeopathic Medical College and Hospital (MBHMC and H), Howrah, West Bengal, India. The outcome measures were homeopathic prescribing indicators (6 items) and patient care indicators (5 items). Individualized homeopathic prescriptions predominated in the encounters. Areas demanding immediate attention were extremely poor labeling of drugs dispensed from the hospital pharmacy, improper record of case history and disease diagnosis, ongoing therapies, and investigational findings in the prescriptions. Internal consistency of the overall instrument was estimated to be good (Cronbach's alpha: Prescribing indicators 0.752 and patient care indicators 0.791). The prescribing indicators, except items 1 and 3, reflected acceptable item-corrected total correlations - Pearson's r from 0.58 (95% CI: 0.52-0.65) to 0.74 (95% CI: 0.69-0.78). The patient care indicators, except item 2, showed acceptable correlations - Pearson's r from 0.40 (95% CI: 0.31-0.48) to 0.82 (95% CI: 0.78-0.85). The instrument also showed high discriminant validity (prescribing indicators P < 0.0001 and patient care indicators P < 0.0001). Improper prescribing practice was quite rampant and corrective measures are warranted. The developed indicators appeared to be validated and reliable; however, they are amendable for further development. PMID:25379474

  16. A Validation Study of Homeopathic Prescribing and Patient Care Indicators

    PubMed Central

    Koley, Munmun; Saha, Subhranil; Ghosh, Shubhamoy; Nag, Goutam; Kundu, Monojit; Mondal, Ramkumar; Purkait, Rajib; Patra, Supratim

    2014-01-01

    A preliminary version of the homeopathic prescribing and patient care indicators was available. The instrument was modified further in this study with an intention to address formally its validity and reliability, audit prescriptions, identify areas of sub-optimal prescribing, and highlight target areas for improving the quality of practices. A cross-sectional study with record analysis was conducted on systematically sampled 377 patients of Mahesh Bhattacharyya Homeopathic Medical College and Hospital (MBHMC and H), Howrah, West Bengal, India. The outcome measures were homeopathic prescribing indicators (6 items) and patient care indicators (5 items). Individualized homeopathic prescriptions predominated in the encounters. Areas demanding immediate attention were extremely poor labeling of drugs dispensed from the hospital pharmacy, improper record of case history and disease diagnosis, ongoing therapies, and investigational findings in the prescriptions. Internal consistency of the overall instrument was estimated to be good (Cronbach's alpha: Prescribing indicators 0.752 and patient care indicators 0.791). The prescribing indicators, except items 1 and 3, reflected acceptable item-corrected total correlations – Pearson's r from 0.58 (95% CI: 0.52-0.65) to 0.74 (95% CI: 0.69-0.78). The patient care indicators, except item 2, showed acceptable correlations – Pearson's r from 0.40 (95% CI: 0.31-0.48) to 0.82 (95% CI: 0.78-0.85). The instrument also showed high discriminant validity (prescribing indicators P < 0.0001 and patient care indicators P < 0.0001). Improper prescribing practice was quite rampant and corrective measures are warranted. The developed indicators appeared to be validated and reliable; however, they are amendable for further development. PMID:25379474

  17. 29 CFR 1607.5 - General standards for validity studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 4 2012-07-01 2012-07-01 false General standards for validity studies. 1607.5 Section 1607.5 Labor Regulations Relating to Labor (Continued) EQUAL EMPLOYMENT OPPORTUNITY COMMISSION UNIFORM GUIDELINES ON EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 1607.5 General standards for validity studies. A. Acceptable types of...

  18. Helping Students Evaluate the Validity of a Research Study.

    ERIC Educational Resources Information Center

    Morgan, George A.; Gliner, Jeffrey A.

    Students often have difficulty in evaluating the validity of a study. A conceptually and linguistically meaningful framework for evaluating research studies is proposed that is based on the discussion of internal and external validity of T. D. Cook and D. T. Campbell (1979). The proposal includes six key dimensions, three related to internal…

  19. Experimental validation of an eddy current probe for defect detection in thick conducting specimen

    NASA Astrophysics Data System (ADS)

    Mahesh Raja, P.; Arunachalam, Kavitha; Balasubramanian, Krishnan

    2016-02-01

    This paper presents numerical modeling and experimental measurements of eddy current (EC) probe for detecting subsurface defects in 10 mm to 15 mm thick conducting specimen. Measurements are presented for a pancake air core coil to detect subsurface defect in 10 mm thick aluminum slab. EC coil parameters namely inner radius(r1), and outer radius(r2), and operating frequency (f) are optimized for deeper penetration in the conducting plate (35 MS/m) for a given coil height(h), and lift off distance (d). Preliminary simulation results are presented for a subsurface defect in 15 mm thick aluminium plate for the optimized EC coil parameters.

  20. Validation study on avermectine residues in foodstuffs.

    PubMed

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

    2011-08-26

    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 μg 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 μg 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

  1. Charge transport studies of proton and ion conducting materials

    NASA Astrophysics Data System (ADS)

    Versek, Craig Wm

    The development of a high-throughput impedance spectroscopy instrumentation platform for conductivity characterization of ion transport materials is outlined. Collaborative studies using this system are summarized. Charge conduction mechanisms and conductivity data for small molecule proton conducting liquids, pyrazole, imidazole, 1,2,3-triazole, 1,2,4-triazole, and select mixtures of these compounds are documented. Furthermore, proton diffusivity measurements using a Pulse Field Gradient Nuclear Magnetic Resonance (PFG NMR) technique for imidazole and 1,2,3-triazole binary mixtures are compared. Studies of azole functionalized discotic and linear mesogens with conductivity, structural, and thermal characterizations are detailed.

  2. PLCO Ovarian Phase III Validation Study — EDRN Public Portal

    Cancer.gov

    Our preliminary data indicate that the performance of CA 125 as a screening test for ovarian cancer can be improved upon by additional biomarkers. With completion of one additional validation step, we will be ready to test the performance of a consensus marker panel in a phase III validation study. Given the original aims of the PLCO trial, we believe that the PLCO represents an ideal longitudinal cohort offering specimens for phase III validation of ovarian cancer biomarkers.

  3. 29 CFR 1607.14 - Technical standards for validity studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... study. Nothing in these guidelines is intended to preclude the development and use of other... used if it provides the information required for the specific validation strategy used. B. Technical... selection procedure by a criterion-related validity strategy should determine whether it is...

  4. An Empirical Study of Reporting Practices Concerning Measurement Validity

    ERIC Educational Resources Information Center

    Hogan, Thomas P.; Agnello, Jessica

    2004-01-01

    This study investigates the current research practice concerning reporting measurement validity evidence based on a sample of 696 research reports listed in the American Psychological Association's Directory of Unpublished Experimental Mental Measures. Only 55% of the reports included any type of validity evidence. This was a substantially lower…

  5. Measuring Long-Distance Romantic Relationships: A Validity Study

    ERIC Educational Resources Information Center

    Pistole, M. Carole; Roberts, Amber

    2011-01-01

    This study investigated aspects of construct validity for the scores of a new long-distance romantic relationship measure. A single-factor structure of the long-distance romantic relationship index emerged, with convergent and discriminant evidence of external validity, high internal consistency reliability, and applied utility of the scores.

  6. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Conduct of studies. 5.15 Section 5.15 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT INTEGRATED LICENSE APPLICATION PROCESS § 5.15 Conduct of studies. (a) Implementation....

  7. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Conducting the comparison study. 761..., AND USE PROHIBITIONS Self-Implementing Alternative Extraction and Chemical Analysis Procedures for Non-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  8. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Conducting the comparison study. 761..., AND USE PROHIBITIONS Self-Implementing Alternative Extraction and Chemical Analysis Procedures for Non-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  9. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Conducting the comparison study. 761..., AND USE PROHIBITIONS Self-Implementing Alternative Extraction and Chemical Analysis Procedures for Non-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  10. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Conducting the comparison study. 761..., AND USE PROHIBITIONS Self-Implementing Alternative Extraction and Chemical Analysis Procedures for Non-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  11. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Conducting the comparison study. 761..., AND USE PROHIBITIONS Self-Implementing Alternative Extraction and Chemical Analysis Procedures for Non-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

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

    ERIC Educational Resources Information Center

    Roberts, Jean

    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…

  13. Validating an Elicited Imitation Task as a Measure of Implicit Knowledge: Comparisons with Other Validation Studies

    ERIC Educational Resources Information Center

    Spada, Nina; Shiu, Julie Li-Ju; Tomita, Yasuyo

    2015-01-01

    This study builds on research investigating the construct validity of elicited imitation (EI) as a measure of implicit second language (L2) grammatical knowledge. It differs from previous studies in that the EI task focuses on a single grammatical feature and time on task is strictly controlled. Seventy-three EFL learners and 20 native English

  14. Validating an Elicited Imitation Task as a Measure of Implicit Knowledge: Comparisons with Other Validation Studies

    ERIC Educational Resources Information Center

    Spada, Nina; Shiu, Julie Li-Ju; Tomita, Yasuyo

    2015-01-01

    This study builds on research investigating the construct validity of elicited imitation (EI) as a measure of implicit second language (L2) grammatical knowledge. It differs from previous studies in that the EI task focuses on a single grammatical feature and time on task is strictly controlled. Seventy-three EFL learners and 20 native English…

  15. Conducting the Salary-Equity Study: A Consultant's View.

    ERIC Educational Resources Information Center

    McLaughlin, Gerald W.; McLaughlin, Josetta S.

    2003-01-01

    A case study approach illustrates the various statistical and political issues that analysts encounter when conducting a salary-equity study for a single institution. Highlights the importance of integrating various stakeholders in the process of assessing salary equity. (EV)

  16. A Validity Study of Environmental Management Concepts.

    ERIC Educational Resources Information Center

    Horn, Jerry G.

    As an outgrowth of a previous study by Roth and others, "Environmental Management Concepts--A List," ED 045 376, this study attempts to determine if there is significant correlation in the taxonomic ranking of selected environmental management concepts as reported by Roth and the ranking of these concepts by teachers of students in grades K-8 for…

  17. Rocky Flats 1990--91 winter validation tracer study: Volume 1

    SciTech Connect

    Brown, K.J.

    1991-10-01

    During the winter of 1990--91, North American Weather Consultants (NAWC) and its subcontractor, ABB Environmental Services (ABBES), conducted a Winter Validation Study (WVS) for EG&G Rocky Flats involving 12 separate tracer experiments conducted between February 3 and February 19, 1991. Six experiments were conducted during nighttime hours and four experiments were conducted during daytime hours. In addition, there was one day/night and one night/day transitional experiment conducted. The primary purpose of the WVS was to gather data to further the approval process for the Terrain Responsive Atmospheric Code (TRAC). TRAC is an atmospheric dispersion model developed and operated at the Department of Energy`s (DOE`s) Rocky Flats Plant (RFP) north of Denver, Colorado. A secondary objective was to gather data that will serve to validate the TRAC model physics.

  18. Sensor data validation and reconstruction. Phase 1: System architecture study

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The sensor validation and data reconstruction task reviewed relevant literature and selected applicable validation and reconstruction techniques for further study; analyzed the selected techniques and emphasized those which could be used for both validation and reconstruction; analyzed Space Shuttle Main Engine (SSME) hot fire test data to determine statistical and physical relationships between various parameters; developed statistical and empirical correlations between parameters to perform validation and reconstruction tasks, using a computer aided engineering (CAE) package; and conceptually designed an expert system based knowledge fusion tool, which allows the user to relate diverse types of information when validating sensor data. The host hardware for the system is intended to be a Sun SPARCstation, but could be any RISC workstation with a UNIX operating system and a windowing/graphics system such as Motif or Dataviews. The information fusion tool is intended to be developed using the NEXPERT Object expert system shell, and the C programming language.

  19. The effects of ion channel blockers validate the conductance-based model of saccadic oscillations.

    PubMed

    Shaikh, Aasef G; Zee, David S; Optican, Lance M; Miura, Kenichiro; Ramat, Stefano; Leigh, R John

    2011-09-01

    Conductance-based models of reciprocally inhibiting burst neurons suggest that intrinsic membrane properties and postinhibitory rebound (PIR) determine the amplitude and frequency of saccadic oscillations. Reduction of the low-threshold calcium currents (I(T)) in the model decreased the amplitude but increased the frequency of the simulated oscillations. Combined reduction of hyperpolarization-activated cation current (I(h)) and I(T) in the model abolished the simulated oscillations. We measured the effects of a selective blocker of I(T) (ethosuximide) in healthy subjects on the amplitude and frequency of saccadic oscillations evoked by eye closure and of a nonselective blocker of I(h) and I(T) (propronolol) in a patient with microsaccadic oscillation and limb tremor syndrome (mSOLT). Ethosuximide significantly reduced the amplitude but increased the frequency of the saccadic oscillations during eye closure in healthy subjects. Propranolol abolished saccadic oscillations in the mSOLT patient. These results support the hypothetical role of postinhibitory rebound, I(h), and I(T) , in generation of saccadic oscillations and determining their kinematic properties. PMID:21950976

  20. Designing SoTL Studies--Part I: Validity

    ERIC Educational Resources Information Center

    Bartsch, Robert A.

    2013-01-01

    This chapter discusses how to improve validity in SoTL studies through generating appropriate measures and using designs that examine causality between an activity and students' performance. [Part II available at EJ1029365.

  1. Conductivity study and correlated barrier hopping (CBH) conduction mechanism in diphosphate compound

    NASA Astrophysics Data System (ADS)

    Ben Taher, Y.; Oueslati, A.; Maaloul, N. K.; Khirouni, K.; Gargouri, M.

    2015-09-01

    In this paper, we report some physical properties of AgAlP2O7 compound obtained through the standard solid-state reaction technique. AgAlP2O7 has been studied by X-ray diffraction, Raman spectroscopy and impedance spectroscopy. The title compound crystallized at room temperature ( T = 300 K) in the monoclinic system with P21/c space group. The electrical properties were studied over a wide range of temperature (440-640 K) in the frequency range of 40 Hz-10 MHz. Study of frequency dependence of AC conductivity suggests that the material obeys the Jonscher's universal dynamic law. The conductivity is equal to 9.37 × 10-5 Ω cm-1 at 640 K, and it is thermally activated with activation energy of 0.76 eV. The variation of DC conductivity with temperature follows the Arrhenius behavior. The calculated values of s decreased with temperature. This behavior reveals that the conduction mechanism is correlated with barrier hopping. The binding energy W m and the hopping distance R ω were deduced.

  2. Job Involvement: A Construct Validity Study.

    ERIC Educational Resources Information Center

    Ruh, Robert A.; White, J. Kenneth

    The interrelationships among job involvement, values, personal background, participation in decision making, and job attitudes were investigated by questionnaire for a sample of 2,775 employees of six manufacturing organizations, representing a 66 percent response rate. The results of this study indicated that job involvement, a basic orientation…

  3. Refinements in the care and use of animals in toxicology studies-regulation, validation, and progress.

    PubMed

    Turner, Patricia V; Smiler, Kathleen L; Hargaden, Maureen; Koch, Michael A

    2003-11-01

    During the past decade, important advances have been made in the humane care and use of laboratory animals used in toxicology studies, and there is strong international interest by the pharmaceutical sector in continuing with this progress. Because of the potential influence on human health, safety studies are highly regulated, and implementing refinements in laboratory animal care and use may require an initial validation study to demonstrate a lack of effect on study outcome. This paper provides an overview of issues surrounding implementation of animal care refinements in toxicology laboratory settings, including regulatory constraints, conducting validation studies, current progress in refinements, and areas for future consideration. PMID:14615954

  4. A Simulation Study of Electrical Fiber Composite Conductivity

    NASA Astrophysics Data System (ADS)

    Mezdour, D.; Sahli, S.

    2008-11-01

    Percolation concept has been used in this study to estimate the amount of conductive fibers embedded in polymeric matrix, necessary to establish conduction in this kind of composites. The resistance of composite materials is calculated by simulating composite samples with different size, containing conductive fibers with various lengths Calculation is based on detecting conductive pathways through the insulating matrix, these pathways are assumed to be resistances in parallel. Electrical resistance curves showed a percolative behavior of the samples versus volume fraction of filler. Lower conduction thresholds are obtained for fiber aspect ratio of 20 and sample size of 100. The electrical resistivity and the conduction thresholds of the carbon fiber reinforced polycarbonate composites have been characterized. Simulation results are in good agreement with an experimental result found in the literature.

  5. Validation Study of the Marianjoy Fall Risk Assessment Tool.

    PubMed

    Ruroede, Kathleen; Pilkington, Donna; Guernon, Ann

    2016-01-01

    Evaluation of fall risk in acute inpatient rehabilitation poses unique challenges. The purpose of this study was to validate an assessment tool for inpatient rehabilitation fall risk identification. This retrospective, descriptive study used a cohort of inpatient rehabilitation patients to evaluate the Marianjoy Fall Risk Assessment Tool reliability and validity. Following implementation of this Tool, fall rates steadily decreased to 49% over 6 years. PMID:26465345

  6. Hyper-X Stage Separation Trajectory Validation Studies

    NASA Technical Reports Server (NTRS)

    Tartabini, Paul V.; Bose, David M.; McMinn, John D.; Martin, John G.; Strovers, Brian K.

    2003-01-01

    An independent twelve degree-of-freedom simulation of the X-43A separation trajectory was created with the Program to Optimize Simulated trajectories (POST II). This simulation modeled the multi-body dynamics of the X-43A and its booster and included the effect of two pyrotechnically actuated pistons used to push the vehicles apart as well as aerodynamic interaction forces and moments between the two vehicles. The simulation was developed to validate trajectory studies conducted with a 14 degree-of-freedom simulation created early in the program using the Automatic Dynamic Analysis of Mechanics Systems (ADAMS) simulation software. The POST simulation was less detailed than the official ADAMS-based simulation used by the Project, but was simpler, more concise and ran faster, while providing similar results. The increase in speed provided by the POST simulation provided the Project with an alternate analysis tool. This tool was ideal for performing separation control logic trade studies that required the running of numerous Monte Carlo trajectories.

  7. 40 CFR 761.386 - Required experimental conditions for the validation study and subsequent use during decontamination.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... experimental conditions apply for any solvent: (a) Temperature and pressure. Conduct the validation study and perform decontamination at room temperature (from ≥15 °C to ≤30 °C) and at atmospheric pressure....

  8. 40 CFR 761.386 - Required experimental conditions for the validation study and subsequent use during decontamination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... experimental conditions apply for any solvent: (a) Temperature and pressure. Conduct the validation study and perform decontamination at room temperature (from ≥15 °C to ≤30 °C) and at atmospheric pressure....

  9. 40 CFR 761.386 - Required experimental conditions for the validation study and subsequent use during decontamination.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... experimental conditions apply for any solvent: (a) Temperature and pressure. Conduct the validation study and perform decontamination at room temperature (from ≥15 °C to ≤30 °C) and at atmospheric pressure....

  10. Conducting Phase IV clinical studies: a moral imperative?

    PubMed Central

    Hill, TP

    2012-01-01

    The answer to this question lies in knowing the moral standing of Phase IV studies and whether we ought to conduct them. And to know this, in part, we need to compare them to studies in Phases I, II, and III and then determine where Phase IV studies stand in relation to Phase I–III studies scientifically and commercially.

  11. The Results of the 1993 Teacher List Validation Study (TLVS). Working Paper Series.

    ERIC Educational Resources Information Center

    Royce, Daniel

    The Teacher List Validation Study was conducted to evaluate the quality of the Teacher Listing Record (TLR), a form used during the Schools and Staffing Survey (SASS) to obtain a list of teachers in each school. The SASS is a set of four inter-related surveys of public and private elementary and secondary schools, districts, teachers, and…

  12. Which Study Designs Are Capable of Producing Valid Evidence about a Program's Effectiveness? A Brief Overview

    ERIC Educational Resources Information Center

    Coalition for Evidence-Based Policy, 2014

    2014-01-01

    This guide is addressed to policy officials, program providers, and researchers who are seeking to: (1) identify and implement social programs backed by valid evidence of effectiveness; or (2) sponsor or conduct an evaluation to determine whether a program is effective. The guide provides a brief overview of which studies can produce valid…

  13. MVII Scores fir Two-Year College Students in Four Vocational Curriculums: A Concurrent Validity Study

    ERIC Educational Resources Information Center

    Bliss, James L.; Smith, Stuart E.

    1977-01-01

    A study of the Minnesota Vocational Interest Inventory (MVII) was conducted to assess its validity for use with students in a new vocational education program at a two-year college. The sample consisted of 390 men and 33 women enrolled in four curriculums. (Author)

  14. The National SAT Validity Study: Sharing Results from Recent College Success Research

    ERIC Educational Resources Information Center

    Shaw, Emily J.; McKenzie, Elizabeth

    2010-01-01

    [Slides] presented at the annual conference of the Southern Association for College Admission Counseling, April 2010. This presentation summarizes recent research from the national SAT Validity Study and includes information on the Admitted Class Evaluation Service (ACES) system and how ACES can help institutions conduct their own validity…

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

    ERIC Educational Resources Information Center

    Gore, Paul A. Jr

    2006-01-01

    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…

  16. Validation study of the USDA’s Data Quality Evaluation System

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    PubMed Central

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

    2013-01-01

    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. PMID:24031157

  18. Human Rights Attitude Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Ercan, Recep; Yaman, Tugba; Demir, Selcuk Besir

    2015-01-01

    The objective of this study is to develop a valid and reliable attitude scale having quality psychometric features that can measure secondary school students' attitudes towards human rights. The study group of the research is comprised by 710 6th, 7th and 8th grade students who study at 4 secondary schools in the centre of Sivas. The study group…

  19. JaCVAM-organized international validation study of the in vivo rodent alkaline comet assay for detection of genotoxic carcinogens: II. Summary of definitive validation study results.

    PubMed

    Uno, Yoshifumi; Kojima, Hajime; Omori, Takashi; Corvi, Raffaella; Honma, Masamistu; Schechtman, Leonard M; Tice, Raymond R; Beevers, Carol; De Boeck, Marlies; Burlinson, Brian; Hobbs, Cheryl A; Kitamoto, Sachiko; Kraynak, Andrew R; McNamee, James; Nakagawa, Yuzuki; Pant, Kamala; Plappert-Helbig, Ulla; Priestley, Catherine; Takasawa, Hironao; Wada, Kunio; Wirnitzer, Uta; Asano, Norihide; Escobar, Patricia A; Lovell, David; Morita, Takeshi; Nakajima, Madoka; Ohno, Yasuo; Hayashi, Makoto

    2015-07-01

    The in vivo rodent alkaline comet assay (comet assay) is used internationally to investigate the in vivo genotoxic potential of test chemicals. This assay, however, has not previously been formally validated. The Japanese Center for the Validation of Alternative Methods (JaCVAM), with the cooperation of the U.S. NTP Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM)/the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), the European Centre for the Validation of Alternative Methods (ECVAM), and the Japanese Environmental Mutagen Society/Mammalian Mutagenesis Study Group (JEMS/MMS), organized an international validation study to evaluate the reliability and relevance of the assay for identifying genotoxic carcinogens, using liver and stomach as target organs. The ultimate goal of this exercise was to establish an Organisation for Economic Co-operation and Development (OECD) test guideline. The study protocol was optimized in the pre-validation studies, and then the definitive (4th phase) validation study was conducted in two steps. In the 1st step, assay reproducibility was confirmed among laboratories using four coded reference chemicals and the positive control ethyl methanesulfonate. In the 2nd step, the predictive capability was investigated using 40 coded chemicals with known genotoxic and carcinogenic activity (i.e., genotoxic carcinogens, genotoxic non-carcinogens, non-genotoxic carcinogens, and non-genotoxic non-carcinogens). Based on the results obtained, the in vivo comet assay is concluded to be highly capable of identifying genotoxic chemicals and therefore can serve as a reliable predictor of rodent carcinogenicity. PMID:26212295

  20. Conductivity and transport studies of plasticized chitosan-based proton conducting biopolymer electrolytes

    NASA Astrophysics Data System (ADS)

    Shukur, M. F.; Yusof, Y. M.; Zawawi, S. M. M.; Illias, H. A.; Kadir, M. F. Z.

    2013-11-01

    This paper focuses on the conductivity and transport properties of chitosan-based solid biopolymer electrolytes containing ammonium thiocyanate (NH4SCN). The sample containing 40 wt% NH4SCN exhibited the highest conductivity value of (1.81 0.50) 10-4 S cm-1 at room temperature. Conductivity has increased to (1.51 0.12) 10-3 S cm-1 with the addition of 25 wt% glycerol. The temperature dependence of conductivity for both salted and plasticized systems obeyed the Arrhenius rule. The activation energy (Ea) was calculated for both systems and it is found that the sample with 40 wt% NH4SCN in the salted system obtained an Ea value of 0.148 eV and that for the sample containing 25 wt% glycerol in the plasticized system is 0.139 eV. From the Fourier transform infrared studies, carboxamide and amine bands shifted to lower wavenumbers, indicating that chitosan has interacted with NH4SCN salt. Changes in the C-O stretching vibration band intensity are observed at 1067 cm-1 with the addition of glycerol. The Rice and Roth model was used to explain the transport properties of the salted and plasticized systems.

  1. AC Conductivity Studies of Lithium Based Phospho Vanadate Glasses

    NASA Astrophysics Data System (ADS)

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

    2011-07-01

    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 σ(ω) = σ(0)+Aωs 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.

  2. Design and Implementation Content Validity Study: Development of an instrument for measuring Patient-Centered Communication

    PubMed Central

    Zamanzadeh, Vahid; Ghahramanian, Akram; Rassouli, Maryam; Abbaszadeh, Abbas; Alavi-Majd, Hamid; Nikanfar, Ali-Reza

    2015-01-01

    Introduction: The importance of content validity in the instrument psychometric and its relevance with reliability, have made it an essential step in the instrument development. This article attempts to give an overview of the content validity process and to explain the complexity of this process by introducing an example. Methods: We carried out a methodological study conducted to examine the content validity of the patient-centered communication instrument through a two-step process (development and judgment). At the first step, domain determination, sampling (item generation) and instrument formation and at the second step, content validity ratio, content validity index and modified kappa statistic was performed. Suggestions of expert panel and item impact scores are used to examine the instrument face validity. Results: From a set of 188 items, content validity process identified seven dimensions includes trust building (eight items), informational support (seven items), emotional support (five items), problem solving (seven items), patient activation (10 items), intimacy/friendship (six items) and spirituality strengthening (14 items). Content validity study revealed that this instrument enjoys an appropriate level of content validity. The overall content validity index of the instrument using universal agreement approach was low; however, it can be advocated with respect to the high number of content experts that makes consensus difficult and high value of the S-CVI with the average approach, which was equal to 0.93. Conclusion: This article illustrates acceptable quantities indices for content validity a new instrument and outlines them during design and psychometrics of patient-centered communication measuring instrument. PMID:26161370

  3. Sample size considerations for the external validation of a multivariable prognostic model: a resampling study.

    PubMed

    Collins, Gary S; Ogundimu, Emmanuel O; Altman, Douglas G

    2016-01-30

    After developing a prognostic model, it is essential to evaluate the performance of the model in samples independent from those used to develop the model, which is often referred to as external validation. However, despite its importance, very little is known about the sample size requirements for conducting an external validation. Using a large real data set and resampling methods, we investigate the impact of sample size on the performance of six published prognostic models. Focussing on unbiased and precise estimation of performance measures (e.g. the c-index, D statistic and calibration), we provide guidance on sample size for investigators designing an external validation study. Our study suggests that externally validating a prognostic model requires a minimum of 100 events and ideally 200 (or more) events. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. PMID:26553135

  4. Emphatic Tendency Scale for Student Teachers: Validity and Reliability Studies

    ERIC Educational Resources Information Center

    Kocak, Canan; Onen, Aysem Seda

    2013-01-01

    The purpose of this study was to analyze the validity and reliability of the Empathic Tendency Scale, which was developed in order to identify student teachers' empathic tendencies. The sampling of the study consisted of 730 student teachers studying at Hacettepe University Faculty of Education. To determine the factor pattern of Empathic…

  5. Validation of GC and HPLC systems for residue studies

    SciTech Connect

    Williams, M.

    1995-12-01

    For residue studies, GC and HPLC system performance must be validated prior to and during use. One excellent measure of system performance is the standard curve and associated chromatograms used to construct that curve. The standard curve is a model of system response to an analyte over a specific time period, and is prima facia evidence of system performance beginning at the auto sampler and proceeding through the injector, column, detector, electronics, data-capture device, and printer/plotter. This tool measures the performance of the entire chromatographic system; its power negates most of the benefits associated with costly and time-consuming validation of individual system components. Other measures of instrument and method validation will be discussed, including quality control charts and experimental designs for method validation.

  6. Study of AC electrical conduction mechanisms in an epoxy polymer

    NASA Astrophysics Data System (ADS)

    Jilani, Wissal; Mzabi, Nissaf; Gallot-Lavallée, Olivier; Fourati, Najla; Zerrouki, Chouki; Zerrouki, Rachida; Guermazi, Hajer

    2015-11-01

    The AC conductivity of an epoxy resin was investigated in the frequency range 10^{-1} - 106 Hz at temperatures ranging from -100 to 120 °C. The frequency dependence of σ_{ac} was described by the law: σ_{ac}=ω \\varepsilon0\\varepsilon^''_{HN}+Aωs. The study of temperature variation of the exponent (s) reveals two conduction models: the AC conduction dependence upon temperature is governed by the small polaron tunneling mechanism (SPTM) at low temperature (-100 -60 °C) and the correlated barrier hopping (CHB) model at high temperature (80-120 °C).

  7. Thermal conductivity of penta-graphene from molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Xu, Wen; Zhang, Gang; Li, Baowen

    2015-10-01

    Using classical equilibrium molecular dynamics simulations and applying the original Tersoff interatomic potential, we study the thermal transport property of the latest two dimensional carbon allotrope, penta-graphene. It is predicted that its room-temperature thermal conductivity is about 167 W/mK, which is much lower than that of graphene. With normal mode decomposition, the accumulated thermal conductivity with respect to phonon frequency and mean free path is analyzed. It is found that the acoustic phonons make a contribution of about 90% to the thermal conductivity, and phonons with mean free paths larger than 100 nm make a contribution over 50%. We demonstrate that the remarkably lower thermal conductivity of penta-graphene compared with graphene results from the lower phonon group velocities and fewer collective phonon excitations. Our study highlights the importance of structure-property relationship and provides better understanding of thermal transport property and valuable insight into thermal management of penta-graphene.

  8. Thermal conductivity of penta-graphene from molecular dynamics study.

    PubMed

    Xu, Wen; Zhang, Gang; Li, Baowen

    2015-10-21

    Using classical equilibrium molecular dynamics simulations and applying the original Tersoff interatomic potential, we study the thermal transport property of the latest two dimensional carbon allotrope, penta-graphene. It is predicted that its room-temperature thermal conductivity is about 167 W/mK, which is much lower than that of graphene. With normal mode decomposition, the accumulated thermal conductivity with respect to phonon frequency and mean free path is analyzed. It is found that the acoustic phonons make a contribution of about 90% to the thermal conductivity, and phonons with mean free paths larger than 100 nm make a contribution over 50%. We demonstrate that the remarkably lower thermal conductivity of penta-graphene compared with graphene results from the lower phonon group velocities and fewer collective phonon excitations. Our study highlights the importance of structure-property relationship and provides better understanding of thermal transport property and valuable insight into thermal management of penta-graphene. PMID:26493918

  9. Comparing the validity of clinician-generated diagnosis of conduct disorder to the diagnostic interview schedule for children.

    PubMed

    Jewell, Jeremy; Handwerk, Michael; Almquist, Julie; Lucas, Christopher

    2004-09-01

    Clinician diagnoses of conduct disorder (CD) were compared to the diagnoses of CD generated by a structured interview against an observed criterion. Participants were 534 youth from a large residential program in the Midwest for delinquent youth. Rates of in-program CD behaviors were gathered from staff observations of the youth over a 9-month time period. Youth diagnosed with CD by the Diagnostic Interview Schedule for Children (DISC) displayed significantly more CD behaviors in the first 6 months of treatment compared to both youth without an externalizing disorder and youth diagnosed with CD by a clinician. Youth diagnosed with CD by a clinician had rates of CD identical to youth without an externalizing disorder. Clinicians may have weighted contextual information more heavily, as this group was significantly more likely to have an arrest record. Results support the use of structured interviews and provide evidence that typical clinician diagnoses may lack adequate validity. PMID:15271611

  10. Radionuclide migration laboratory studies for validation of batch sorption data

    SciTech Connect

    Triay, I.R.; Mitchell, A.J.; Ott, M.A.

    1991-12-31

    Advective and diffusive migration experiments (within the Dynamic Transport Column Experiments and Diffusion Studies of the Yucca Mountain Site Characterization Project) involve utilizing crushed material, intact, and fractured tuff in order to test and improve (if necessary) transport models by experimentally observing the migration of sorbing and non-sorbing radionuclides on a laboratory scale. Performing a validation of the sorption data obtained with batch techniques (within the Batch Sorption Study) is an integral part of the mission of the Dynamic Transport Column Experiments and Diffusion Studies. In this paper the work scope of the radionuclide migration laboratory experiments (as they apply to validation of batch sorption data) is reviewed.

  11. 41 CFR 60-3.5 - General standards for validity studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., content, and construct validity. Evidence of the validity of a test or other selection procedure by a... this part. Evidence of the validity of a test or other selection procedure by a content validity study.... Evidence of the validity of a test or other selection procedure through a construct validity study...

  12. 41 CFR 60-3.5 - General standards for validity studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., content, and construct validity. Evidence of the validity of a test or other selection procedure by a... this part. Evidence of the validity of a test or other selection procedure by a content validity study.... Evidence of the validity of a test or other selection procedure through a construct validity study...

  13. 41 CFR 60-3.5 - General standards for validity studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., content, and construct validity. Evidence of the validity of a test or other selection procedure by a... this part. Evidence of the validity of a test or other selection procedure by a content validity study.... Evidence of the validity of a test or other selection procedure through a construct validity study...

  14. 41 CFR 60-3.5 - General standards for validity studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., content, and construct validity. Evidence of the validity of a test or other selection procedure by a... this part. Evidence of the validity of a test or other selection procedure by a content validity study.... Evidence of the validity of a test or other selection procedure through a construct validity study...

  15. 41 CFR 60-3.5 - General standards for validity studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., content, and construct validity. Evidence of the validity of a test or other selection procedure by a... this part. Evidence of the validity of a test or other selection procedure by a content validity study.... Evidence of the validity of a test or other selection procedure through a construct validity study...

  16. The electrical conduction of conjugated molecular CAMs studied by a conductive atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Yamamoto, Shin-ichi; Ogawa, Kazufumi

    2006-09-01

    Monomolecular layers containing pyrrolyl groups between two parallel Pt electrodes on a glass substrate by a chemical adsorption technique using N-[11-(trichlorosilyl)undecyl] pyrrole (PNN) were studied. Polymerization with pure water by applying a DC voltage of 10 V between the two Pt electrodes was carried out, and several electric paths were formed between the two Pt electrodes were identified. Conductive probe of an atomic force microscopy (AFM) was used to examine the electrical polymerized paths through the surface of the polypyrrolyl group in a chemically adsorbed monomolecular layer. With a measurement volume of about 0.2 nm (thickness of the monomolecular layer) × 100 μm (the average width of an electric path) × 100 μm (the distance between the Pt electrode and the Au-covered AFM tip), the resistance at room temperature of one electric path was 5 kΩ under ambient conditions. From the results conducted in an atmosphere, the conductivity of a super-long conjugated polypyrrolyl group without any dopant in a lateral direction was ohmically estimated to be at least 5.0 × 10 5 s/m.

  17. Electrical studies on silver based fast ion conducting glassy materials

    SciTech Connect

    Rao, B. Appa Kumar, E. Ramesh Kumari, K. Rajani Bhikshamaiah, G.

    2014-04-24

    Among all the available fast ion conductors, silver based glasses exhibit high conductivity. Further, glasses containing silver iodide enhances fast ion conducting behavior at room temperature. Glasses of various compositions of silver based fast ion conductors in the AgI−Ag{sub 2}O−[(1−x)B{sub 2}O{sub 3}−xTeO{sub 2}] (x=0 to1 mol% in steps of 0.2) glassy system have been prepared by melt quenching method. The glassy nature of the compounds has been confirmed by X-ray diffraction. The electrical conductivity (AC) measurements have been carried out in the frequency range of 1 KHz–3MHz by Impedance Analyzer in the temperature range 303–423K. The DC conductivity measurements were also carried out in the temperature range 300–523K. From both AC and DC conductivity studies, it is found that the conductivity increases and activation energy decreases with increasing the concentration of TeO{sub 2} as well as with temperature. The conductivity of the present glass system is found to be of the order of 10{sup −2} S/cm at room temperature. The ionic transport number of these glasses is found to be 0.999 indicating that these glasses can be used as electrolyte in batteries.

  18. Electrical studies on silver based fast ion conducting glassy materials

    NASA Astrophysics Data System (ADS)

    Rao, B. Appa; Kumar, E. Ramesh; Kumari, K. Rajani; Bhikshamaiah, G.

    2014-04-01

    Among all the available fast ion conductors, silver based glasses exhibit high conductivity. Further, glasses containing silver iodide enhances fast ion conducting behavior at room temperature. Glasses of various compositions of silver based fast ion conductors in the AgI-Ag2O-[(1-x)B2O3-xTeO2] (x=0 to1 mol% in steps of 0.2) glassy system have been prepared by melt quenching method. The glassy nature of the compounds has been confirmed by X-ray diffraction. The electrical conductivity (AC) measurements have been carried out in the frequency range of 1 KHz-3MHz by Impedance Analyzer in the temperature range 303-423K. The DC conductivity measurements were also carried out in the temperature range 300-523K. From both AC and DC conductivity studies, it is found that the conductivity increases and activation energy decreases with increasing the concentration of TeO2 as well as with temperature. The conductivity of the present glass system is found to be of the order of 10-2 S/cm at room temperature. The ionic transport number of these glasses is found to be 0.999 indicating that these glasses can be used as electrolyte in batteries.

  19. Verification, Validation and Sensitivity Studies in Computational Biomechanics

    PubMed Central

    Anderson, Andrew E.; Ellis, Benjamin J.; Weiss, Jeffrey A.

    2012-01-01

    Computational techniques and software for the analysis of problems in mechanics have naturally moved from their origins in the traditional engineering disciplines to the study of cell, tissue and organ biomechanics. Increasingly complex models have been developed to describe and predict the mechanical behavior of such biological systems. While the availability of advanced computational tools has led to exciting research advances in the field, the utility of these models is often the subject of criticism due to inadequate model verification and validation. The objective of this review is to present the concepts of verification, validation and sensitivity studies with regard to the construction, analysis and interpretation of models in computational biomechanics. Specific examples from the field are discussed. It is hoped that this review will serve as a guide to the use of verification and validation principles in the field of computational biomechanics, thereby improving the peer acceptance of studies that use computational modeling techniques. PMID:17558646

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

    ERIC Educational Resources Information Center

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

    2012-01-01

    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…

  1. The Jackson Career Explorer: Two Further Validity Studies

    ERIC Educational Resources Information Center

    Schermer, Julie Aitken

    2012-01-01

    The present report consists of two further validity studies using the Jackson Career Explorer (JCE), a short form and continuous version of the Jackson Vocational Interest Survey, measuring 34 interests. The first study examined the relationships between the JCE and five personality factors, from a sample of 528 individuals. The correlations found…

  2. 40 CFR 761.392 - Preparing validation study samples.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Preparing validation study samples. 761.392 Section 761.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT POLYCHLORINATED BIPHENYLS (PCBs) MANUFACTURING, PROCESSING, DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Comparison Study...

  3. [The "Neuropsychological Screening Test (NST)": initial validation and reliability studies].

    PubMed

    Schmidgen, H; Hoell, T; Regard, M; Landis, T; Rudolf, K H; Berzewski, H; Brock, M

    1994-01-01

    Medical examinations only insufficiently measure cognitive impairment in neurological and neurosurgical patients. Due to costs an personnel shortages, adequate neuropsychological test methods are typically bypassed. Indeed, the very size and methodological problems of current tests impede their application in clinical practice. To resolve this dissatisfying state of affairs, we have developed a standardized, scored form of initial neuropsychological examination. The Neuropsychological Screening Test (NST) comprises 45 items, is easy to handle, and can be conducted in 15-20 min. The NST measures psychic performance along functional parameters such as orientation in place and time, primary and secondary language, visuospatial ability, attention, and memory skills. We have assessed the validity and reliability of the NST in a prospective study. 129 neurosurgical patients (60% malignant or benign cerebral tumors, 21% vascular malformations with and without subarachnoid hemorrhage, 6% traumatic brain injury, 3% hydrocephalus, 10% others) and 52 control subjects were included in the study. The difference in average total NST-scores was highly significant for the two groups (t = -7.84, DF = 177.93, p < .001). In addition, two chronologically separate subsamples of NCH patients (N = 81) and controls (N = 35) were tested using the Mini-Mental State (MMS). The correlation between total NST-score and MMS results was r = .49 (p < .001). Cross-tabulation was used to set a cut-off score, by means of which 80% of the neurosurgical patients were identified as true positive and 74% of the controls as true negative. A 24-hour retest confirmed the NST as reliable to .85 (p < .001).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7887046

  4. Low thermal conductivity of graphyne nanotubes from molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Hu, Ming; Jing, Yuhang; Zhang, Xiaoliang

    2015-04-01

    It is well known that carbon nanotubes (CNTs) possess ultrahigh thermal conductivity that is comparable to bulk diamond. However, no research has studied the possible low thermal conductivity of different CNTs so far. By performing nonequilibrium molecular dynamic simulations, we reveal that the perfect graphyne nanotube (GNT) exhibits an unprecedentedly low thermal conductivity (below 10 W/mK at room temperature), which is generally two orders of magnitude lower than that of ordinary CNTs and even lower than the values reported for defected, doped, and chemically functionalized CNTs. By performing phonon polarization and spectral energy density analysis, we observe that the ultralow thermal conductivity stems from the unique atomic structure of the GNT, consisting of the weak acetylenic linkage (s p C-C bonds) and the strong hexagonal ring (s p2 C-C bonds), which results in a large vibrational mismatch between these two components, and thus induces significantly inefficient heat transfer. Moreover, the thermal transport in GNT with a large number of acetylenic linkages is dominated by the low frequency longitudinal modes in the linkage. Such strong confinement of the low frequency thermal energy results in the extremely low thermal conductivity due to the flattened phonon dispersion curves (low phonon group velocities). The exploration of the abnormal thermal transport of GNTs paves the way for design and application of the relevant devices that could benefit from the ultralow thermal conductivity, such as thermoelectrics for energy conversion.

  5. Paraphasias in Multilingual Conduction Aphasia: A Single Case Study

    ERIC Educational Resources Information Center

    Hegde, Medha; Bhat, Sapna

    2007-01-01

    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…

  6. Treatment of Conduct Disorders in Childhood: A Comparative Study.

    ERIC Educational Resources Information Center

    Robinson, Elizabeth A.

    Children evidencing conduct disorders comprise the bulk of clinical referrals. Longitudinal studies have found that the prognosis for these children is poor in that the majority exhibit antisocial behavior in adulthood. In order to compare two methods of treatment, relationship-based and contingency management, 53 children (33 boys, 20 girls),…

  7. Conducting Community-Impact Studies: A Handbook for Community Colleges.

    ERIC Educational Resources Information Center

    Armijo, J. Frank; And Others

    Produced as part of the Targeted Outcomes Field Development Project, this handbook provides basic guidelines that can be used by community colleges for organizing and conducting community impact studies. An introductory chapter touches on the broad range of economic, educational, social, and technological impacts which community colleges have upon…

  8. Estimating Unsaturated Hydraulic Conductivity: Study the Effect of Tortuosity Factor

    NASA Astrophysics Data System (ADS)

    Ghanbarian-Alavijeh, Behzad; Abbasi, Fariborz

    2010-05-01

    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.

  9. Instruments for the assessment of social anxiety disorder: Validation studies

    PubMed Central

    Osório, Flávia de Lima; Crippa, José Alexandre de Souza; Loureiro, Sonia Regina

    2012-01-01

    Great progress has been observed in the literature over the last decade regarding the validation of instruments for the assessment of Social Anxiety Disorder in the Brazilian context. Particularly outstanding in this respect is the production of a group of Brazilian investigators regarding the psychometric study of the following instruments: Liebowitz Social Anxiety Scale, Social Phobia Inventory, Brief Social Phobia Scale, Disability Profile, Liebowitz Self-Rated Disability Scale, Social Phobia Safety Behaviors Scale and Self-Statements During Public Speaking Scale, which have proved to be appropriate and valid for use in the adult Brazilian population, representing resources for the assessment of social anxiety in clinical and experimental situations. PMID:24175172

  10. A Validity Study of the Self-Esteem Inventory.

    ERIC Educational Resources Information Center

    Landis, H. John

    Results of this validation study of a slightly modified version of the Coppersmith Self-Esteem Inventory substantiate its use with seventh graders to assess Goal I (concerning self-understanding and appreciation of self-worth) of the Educational Quality Assessment Program in Pennsylvania. Appendixes include the definition and rationale for Goal I,…

  11. Homework Purpose Scale for Middle School Students: A Validation Study

    ERIC Educational Resources Information Center

    Xu, Jianzhong

    2011-01-01

    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

  12. Understanding Foreign Language Learning Strategies: A Validation Study

    ERIC Educational Resources Information Center

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

    2013-01-01

    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…

  13. Dimensions of Intuition: First-Round Validation Studies

    ERIC Educational Resources Information Center

    Vrugtman, Rosanne

    2009-01-01

    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…

  14. Rap-Music Attitude and Perception Scale: A Validation Study

    ERIC Educational Resources Information Center

    Tyson, Edgar H.

    2006-01-01

    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…

  15. Reflective Thinking Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Basol, Gulsah; Evin Gencel, Ilke

    2013-01-01

    The purpose of this study was to adapt Reflective Thinking Scale to Turkish and investigate its validity and reliability over a Turkish university students' sample. Reflective Thinking Scale (RTS) is a 5 point Likert scale (ranging from 1 corresponding Agree Completely, 3 to Neutral, and 5 to Not Agree Completely), purposed to measure…

  16. Homework Purpose Scale for Middle School Students: A Validation Study

    ERIC Educational Resources Information Center

    Xu, Jianzhong

    2011-01-01

    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…

  17. Teachers' Engagement at Work: An International Validation Study

    ERIC Educational Resources Information Center

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

    2012-01-01

    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…

  18. Research Measures for Dyscalculia: A Validity and Reliability Study.

    ERIC Educational Resources Information Center

    Geiman, R. M.

    1986-01-01

    This study sought to evaluate a measure of dyscalculia to determine its validity and reliability. It also tested use of the instrument with seventh graders and ascertained where errors attributed to dyscalculia were also present in an average sample of seventh graders. Results varied. (MNS)

  19. Internal Validity Studies of a Telephone Preemployment Measure.

    ERIC Educational Resources Information Center

    Gerstein, Lawrence H.; And Others

    1989-01-01

    Data are presented on the validity and reliability of a new form of employee honesty testing: "The Integrity Interview." Results indicated that this instrument was a reliable alternative to commonly used written measures, although further study is needed to establish normative data across different employee populations and settings. (Author/TE)

  20. A Validation Study of Early Adolescents' Pubertal Self-Assessments

    ERIC Educational Resources Information Center

    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

    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,…

  1. A Validation Study of the Existential Anxiety Scale.

    ERIC Educational Resources Information Center

    Hullett, Michael A.

    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…

  2. Rap-Music Attitude and Perception Scale: A Validation Study

    ERIC Educational Resources Information Center

    Tyson, Edgar H.

    2006-01-01

    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

  3. 40 CFR 761.392 - Preparing validation study samples.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Preparing validation study samples. 761.392 Section 761.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... concentrations of PCBs as measured by a standard wipe sample, contaminate a minimum of 10 surfaces....

  4. 40 CFR 761.392 - Preparing validation study samples.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Preparing validation study samples. 761.392 Section 761.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... concentrations of PCBs as measured by a standard wipe sample, contaminate a minimum of 10 surfaces....

  5. 40 CFR 761.392 - Preparing validation study samples.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Preparing validation study samples. 761.392 Section 761.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... concentrations of PCBs as measured by a standard wipe sample, contaminate a minimum of 10 surfaces....

  6. 40 CFR 761.392 - Preparing validation study samples.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Preparing validation study samples. 761.392 Section 761.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... concentrations of PCBs as measured by a standard wipe sample, contaminate a minimum of 10 surfaces....

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

    SciTech Connect

    Burns, J.M.

    1991-01-01

    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.

  8. Ab-initio study of napthelene based conducting polymer

    NASA Astrophysics Data System (ADS)

    Ruhela, Ankur; Kanchan, Reena; Srivastava, Anurag; Sinha, O. P.

    2014-04-01

    In this paper, we have identified structural and electronic properties of conducting polymers by using DFT based ATK-VNL ab-initio tool. Naphthalene derivative structures were stabilized by varying the bond length between two atoms of the molecule C-N and C-C. We have also studied the molecular energy spectrum of naphthalene derivatives and found the HOMOLUMO for the same. A comparison of structural and electronic properties of naphthalene derivatives by attaching the functional group of amine, have been performed and found that they show good semi conducting properties.

  9. Ab-initio study of napthelene based conducting polymer

    SciTech Connect

    Ruhela, Ankur; Kanchan, Reena; Srivastava, Anurag; Sinha, O. P.

    2014-04-24

    In this paper, we have identified structural and electronic properties of conducting polymers by using DFT based ATK-VNL ab-initio tool. Naphthalene derivative structures were stabilized by varying the bond length between two atoms of the molecule C-N and C-C. We have also studied the molecular energy spectrum of naphthalene derivatives and found the HOMOLUMO for the same. A comparison of structural and electronic properties of naphthalene derivatives by attaching the functional group of amine, have been performed and found that they show good semi conducting properties.

  10. Preparation, characterization and conductivity studies of chlorinated natural rubber

    NASA Astrophysics Data System (ADS)

    M, Subburaj; Ramesan, M. T.; Pradyumnan, P. P.

    2014-10-01

    Chlorinated natural rubber (CNR) was prepared by alkaline hydrolysis of chloroform using phase transfer catalyst. The chlorination in CNR was monitored by FTIR and UV spectroscopy and these studies indicated the formation of dichloro cyclopropyl ring to the double bond of natural rubber (NR). XRD and SEM analysis revealed the extent of chlorination in natural rubber. Electrical properties such as AC conductivity, dielectric constant and dielectric loss of CNR was higher than that of NR. Conductivity of NR increased with the increase in the concentration of chlorine percentage. LOI values indicated that the chemical modification imparts better flame resistant to NR.

  11. The Functional Independence Measure: a comparative validity and reliability study.

    PubMed

    Kidd, D; Stewart, G; Baldry, J; Johnson, J; Rossiter, D; Petruckevitch, A; Thompson, A J

    1995-01-01

    The majority of measurement scales used to evaluate outcome in rehabilitation are ordinal in nature and consequently statistically valid assessments of change are difficult to make. The Functional Independence Measure (FIM) can be weighted to possess interval properties, potentially allowing more accurate analysis of change. In this study the FIM was compared to the Barthel Index (BI) to determine its validity, reliability and ease of use in two groups of 25 patients undergoing neurorehabilitation. The FIM was considered to be more valid than the BI, and equally reliable in the assessment of disability. When the two disability scores were compared using subjective and objective assessment the agreement between them was comparable, although neither was high. PMID:7858276

  12. NASA's Rodent Research Project: Validation of Flight Hardware, Operations and Science Capabilities for Conducting Long Duration Experiments in Space

    NASA Technical Reports Server (NTRS)

    Choi, S. Y.; Beegle, J. E.; Wigley, C. L.; Pletcher, D.; Globus, R. K.

    2015-01-01

    Research using rodents is an essential tool for advancing biomedical research on Earth and in space. Rodent Research (RR)-1 was conducted to validate flight hardware, operations, and science capabilities that were developed at the NASA Ames Research Center. Twenty C57BL/6J adult female mice were launched on Sept 21, 2014 in a Dragon Capsule (SpaceX-4), then transferred to the ISS for a total time of 21-22 days (10 commercial mice) or 37 (10 validation mice). Tissues collected on-orbit were either rapidly frozen or preserved in RNA later at less than or equal to -80 C (n=2/group) until their return to Earth. Remaining carcasses were rapidly frozen for dissection post-flight. The three controls groups at Kennedy Space Center consisted of: Basal mice euthanized at the time of launch, Vivarium controls, housed in standard cages, and Ground Controls (GC), housed in flight hardware within an environmental chamber. FLT mice appeared more physically active on-orbit than GC, and behavior analysis are in progress. Upon return to Earth, there were no differences in body weights between FLT and GC at the end of the 37 days in space. RNA was of high quality (RIN greater than 8.5). Liver enzyme activity levels of FLT mice and all control mice were similar in magnitude to those of the samples that were optimally processed in the laboratory. Liver samples collected from the intact frozen FLT carcasses had RNA RIN of 7.27 +/- 0.52, which was lower than that of the samples processed on-orbit, but similar to those obtained from the control group intact carcasses. Nonetheless, the RNA samples from the intact carcasses were acceptable for the most demanding transcriptomic analyses. Adrenal glands, thymus and spleen (organs associated with stress response) showed no significant difference in weights between FLT and GC. Enzymatic activity was also not significantly different. Over 3,000 tissues collected from the four groups of mice have become available for the Biospecimen Sharing Program. Together, these validation flight findings demonstrate the capability to support long-duration RR on the ISS to achieve both basic science and biomedical objectives.

  13. Heat conduction in multifunctional nanotrusses studied using Boltzmann transport equation

    NASA Astrophysics Data System (ADS)

    Dou, Nicholas G.; Minnich, Austin J.

    2016-01-01

    Materials that possess low density, low thermal conductivity, and high stiffness are desirable for engineering applications, but most materials cannot realize these properties simultaneously due to the coupling between them. Nanotrusses, which consist of hollow nanoscale beams architected into a periodic truss structure, can potentially break these couplings due to their lattice architecture and nanoscale features. In this work, we study heat conduction in the exact nanotruss geometry by solving the frequency-dependent Boltzmann transport equation using a variance-reduced Monte Carlo algorithm. We show that their thermal conductivity can be described with only two parameters, solid fraction and wall thickness. Our simulations predict that nanotrusses can realize unique combinations of mechanical and thermal properties that are challenging to achieve in typical materials.

  14. Ride qualities criteria validation/pilot performance study: Flight test results

    NASA Technical Reports Server (NTRS)

    Nardi, L. U.; Kawana, H. Y.; Greek, D. C.

    1979-01-01

    Pilot performance during a terrain following flight was studied for ride quality criteria validation. Data from manual and automatic terrain following operations conducted during low level penetrations were analyzed to determine the effect of ride qualities on crew performance. The conditions analyzed included varying levels of turbulence, terrain roughness, and mission duration with a ride smoothing system on and off. Limited validation of the B-1 ride quality criteria and some of the first order interactions between ride qualities and pilot/vehicle performance are highlighted. An earlier B-1 flight simulation program correlated well with the flight test results.

  15. AC Conductivity Studies of Lithium Based Phospho Vanadate Glasses

    SciTech Connect

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

    2011-07-15

    Glasses in the system xLi{sub 2}SO{sub 4}-20Li{sub 2}O-(80-x) [80P{sub 2}O{sub 5}-20V{sub 2}O{sub 5}](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 Li{sub 2}SO{sub 4} concentration. The ac conductivities have been fitted to the Almond-West type single power law equation {sigma}({omega}) = {sigma}(0)+A{omega}{sup s} where 's' is the power law exponent. The ac conductivity found to increase with increase of Li{sub 2}SO{sub 4} concentration. An attempt is made to elucidate the enhancement of lithium ion conduction in phosphor-vanadate glasses by considering the expansion of network structure.

  16. Time resolved strain dependent morphological study of electrically conducting nanocomposites

    NASA Astrophysics Data System (ADS)

    Khan, Imran; Mitchell, Geoffrey; Mateus, Artur; Kamma-Lorger, Christina S.

    2015-10-01

    An efficient and reliable method is introduced to understand the network behaviour of nano-fillers in a polymeric matrix under uniaxial strain coupled with small angle x-ray scattering measurements. The nanoparticles (carbon nanotubes) are conductive and the particles form a percolating network that becomes apparent source of electrical conduction and consequently the samples behave as a bulk conductor. Polyurethane based nanocomposites containing 2% w/w multiwall carbon nanotubes are studied. The electrical conductivity of the nanocomposite was (3.28×10-5s/m).The sample was able to be extended to an extension ratio of 1.7 before fracture. A slight variation in the electrical conductivity is observed under uniaxial strain which we attribute to the disturbance of conductive pathways. Further, this work is coupled with in- situ time resolved small angle x-ray scattering measurements using a synchrotron beam line to enable its measurements to be made during the deformation cycle. We use a multiscale structure to model the small angle x-ray data. The results of the analysis are interpreted as the presence of aggregates which would also go some way towards understanding why there is no alignment of the carbon nanotubes.

  17. Environmental education curriculum evaluation questionnaire: A reliability and validity study

    NASA Astrophysics Data System (ADS)

    Minner, Daphne Diane

    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.

  18. Sources of Self-Efficacy in Mathematics: A Validation Study

    ERIC Educational Resources Information Center

    Usher, Ellen L.; Pajares, Frank

    2009-01-01

    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.…

  19. External validity of conduct and oppositional defiant disorders determined by the NIMH Diagnostic Interview Schedule for children.

    PubMed

    Friman, P C; Handwerk, M L; Smith, G L; Larzelere, R E; Lucas, C P; Shaffer, D M

    2000-06-01

    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 over the course of that year. Results from hierarchical linear modeling analyses showed significant discriminative relationships between results from the DISC and the independent observations. Specifically, observations of symptomatic behaviors (CD or ODD) decreased for youth who met diagnostic criteria at the first administration of the DISC but not at the second, increased for youth who did not meet criteria at the first administration but did at the second, and did not change for youth who met criteria at both administrations. These results extend the data on the validity of the DISC and support continued research efforts to determine its clinical utility. PMID:10885685

  20. Temporal study of wake formation behind a conducting body

    NASA Astrophysics Data System (ADS)

    Meassick, S.; Chan, C.; Qian, Y.; Sroda, T.; Azar, T.

    1991-08-01

    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.

  1. Temporal study of wake formation behind a conducting body

    NASA Technical Reports Server (NTRS)

    Meassick, S.; Chan, C.; Qian, Y.; Sroda, T.; Azar, T.

    1991-01-01

    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.

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

    SciTech Connect

    Li, Tingwen

    2012-04-01

    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.

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

    SciTech Connect

    Li, Tingwen; Garg, Rahul; Galvin, Janine; Pannala, Sreekanth

    2012-01-01

    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.

  4. Sexual behavioral abstine HIV/AIDS questionnaire: Validation study of an Iranian questionnaire

    PubMed Central

    Najarkolaei, Fatemeh Rahmati; Niknami, Shamsaddin; Shokravi, Farkhondeh Amin; Tavafian, Sedigheh Sadat; Fesharaki, Mohammad Gholami; Jafari, Mohammad Reza

    2014-01-01

    Background: This study was designed to assess the validity and reliability of the designed sexual, behavioral abstinence, and avoidance of high-risk situation questionnaire (SBAHAQ), with an aim to construct an appropriate development tool in the Iranian population. Materials and Methods: A descriptive–analytic study was conducted among female undergraduate students of Tehran University, who were selected through cluster random sampling. After reviewing the questionnaires and investigating face and content validity, internal consistency of the questionnaire was assessed by Cronbach's alpha. Explanatory and confirmatory factor analysis was conducted using SPSS and AMOS 16 Software, respectively. Results: The sample consisted of 348 female university students with a mean age of 20.69 ± 1.63 years. The content validity ratio (CVR) coefficient was 0.85 and the reliability of each section of the questionnaire was as follows: Perceived benefit (PB; 0.87), behavioral intention (BI; 0.77), and self-efficacy (SE; 0.85) (Cronbach's alpha totally was 0.83). Explanatory factor analysis showed three factors, including SE, PB, and BI, with the total variance of 61% and Kaiser–Meyer–Olkin (KMO) index of 88%. These factors were also confirmed by confirmatory factor analysis [adjusted goodness of fitness index (AGFI) = 0.939, root mean square error of approximation (RMSEA) = 0.039]. Conclusion: This study showed the designed questionnaire provided adequate construct validity and reliability, and could be adequately used to measure sexual abstinence and avoidance of high-risk situations among female students. PMID:24741650

  5. [New studies question the cardiac safety of conducted electrical weapons].

    PubMed

    Thomsen, Jakob Hartvig; Kjærgaard, Jesper; Hassager, Christian; Graff, Claus; Hansen, John; Worbech, Thomas; Jensen, Jens Henning; Bro-Jeppesen, John; Pehrson, Steen

    2015-06-01

    Conducted electrical weapons (CEW) were invented in the 1970s and are now widely used by more than 16,000 military and law enforcement agencies worldwide. Recent studies have sug­gested that a causal relation of cardiac arrest in humans and utilization of CEW may exist and cardiac capture and fatal arrhythmia have been documented in animal studies. We believe, based on current knowledge, that CEW use may have caused human fatalities. Users should be aware of potential serious side effects and be able to provide basic life support. PMID:25765125

  6. Optical study on conducting polymer-based field effect devices

    NASA Astrophysics Data System (ADS)

    Kim, Youngmin; Hsu, Fang-Chi; Chiou, Nan-Rong; Park, June Hyoung; Waldmann, Oliver; Prigodin, Vladimir; Epstein, Arthur J.

    2003-03-01

    ¡°Optical study on conducting polymer-based field effect devices ¡° Y.M. Kim, F.C. Hsu, N.R. Chiou, J.H. Park, O. Waldmann, V.N. Prigodin, A. J. Epstein, The Ohio State University Time variation of source-drain current with gate modulation of conducting polymer-based field effect devices was studied by in-situ mid-infrared(MIR) reflectance measurements. The transistor-like field effect devices were fabricated using aluminum gate which also works as an optically reflective layer, several different insulating polymers, and poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonic acid)(PEDOT/PSS) active layer. The MIR reflectance measurement of the response to application of a gate voltage shows reflectivity change proportional to the source-drain current variation, shift in interference pattern, and no significant change in phonon features. For the specular reflectance measurement, about 1cm x 1cm area, and 0.1 1 micron thick active layer was prepared, and the insulating layer thickness was also 0.1 1 micron. Because of the small thickness compared to the penetration depth of the PEDOT/PSS, there are the transmission dominant region and the reflectance dominant region, and the reflectivity was increased in the transmission dominant and decreased and in the reflectance dominant region. The results are compared with models for the field effect control of conductance of doped polymers. Supported by ONR Grant No. N00014-01-1-0427.

  7. Paper use in research ethics applications and study conduct.

    PubMed

    Chakladar, Abhijoy; Eckstein, Sue; White, Stuart M

    2011-02-01

    Application for Research Ethics Committee (REC) approval and the conduct of medical research is paper intensive. This retrospective study examined all applications to a single REC in the south of England over one year. It estimated the mass of paper used, comparing the proportional paper consumption of different trial types and during different stages of the research process, quantifying the consumption in terms of carbon dioxide emissions. In 2009, 68 trials were submitted to the REC. Total paper consumption for the REC process and study conduct was 176,150 sheets of A4 paper (879 kg), equivalent to an estimated 11.5 million sheets (88 tonnes, 2100 trees) a year for the U.K.; the REC process accounted for 26.4%. REC applications and the conduct of approved trials generate considerable environmental impact through paper consumption contributing to the NHS's carbon footprint. Paper use might be reduced through the implementation of digital technologies and revised research methods, namely changing attitudes in both researchers and ethics committees. PMID:21404784

  8. A content validity study of signs, symptoms and diseases/health problems expressed in LIBRAS1

    PubMed Central

    Aragão, Jamilly da Silva; de França, Inacia Sátiro Xavier; Coura, Alexsandro Silva; de Sousa, Francisco Stélio; Batista, Joana D'arc Lyra; Magalhães, Isabella Medeiros de Oliveira

    2015-01-01

    Objectives: to validate the content of signs, symptoms and diseases/health problems expressed in LIBRAS for people with deafness Method: methodological development study, which involved 36 people with deafness and three LIBRAS specialists. The study was conducted in three stages: investigation of the signs, symptoms and diseases/health problems, referred to by people with deafness, reported in a questionnaire; video recordings of how people with deafness express, through LIBRA, the signs, symptoms and diseases/health problems; and validation of the contents of the recordings of the expressions by LIBRAS specialists. Data were processed in a spreadsheet and analyzed using univariate tables, with absolute frequencies and percentages. The validation results were analyzed using the Content Validity Index (CVI). Results: 33 expressions in LIBRAS, of signs, symptoms and diseases/health problems were evaluated, and 28 expressions obtained a satisfactory CVI (1.00). Conclusions: the signs, symptoms and diseases/health problems expressed in LIBRAS presented validity, in the study region, for health professionals, especially nurses, for use in the clinical anamnesis of the nursing consultation for people with deafness. PMID:26625991

  9. Design, development, testing and validation of a Photonics Virtual Laboratory for the study of LEDs

    NASA Astrophysics Data System (ADS)

    Naranjo, Francisco L.; Martínez, Guadalupe; Pérez, Ángel L.; Pardo, Pedro J.

    2014-07-01

    This work presents the design, development, testing and validation of a Photonic Virtual Laboratory, highlighting the study of LEDs. The study was conducted from a conceptual, experimental and didactic standpoint, using e-learning and m-learning platforms. Specifically, teaching tools that help ensure that our students perform significant learning have been developed. It has been brought together the scientific aspect, such as the study of LEDs, with techniques of generation and transfer of knowledge through the selection, hierarchization and structuring of information using concept maps. For the validation of the didactic materials developed, it has been used procedures with various assessment tools for the collection and processing of data, applied in the context of an experimental design. Additionally, it was performed a statistical analysis to determine the validity of the materials developed. The assessment has been designed to validate the contributions of the new materials developed over the traditional method of teaching, and to quantify the learning achieved by students, in order to draw conclusions that serve as a reference for its application in the teaching and learning processes, and comprehensively validate the work carried out.

  10. Dietary Assessment in the California Teachers Study: Reproducibility and Validity

    PubMed Central

    Horn-Ross, Pamela L.; Lee, Valerie S.; Collins, Christine N.; Stewart, Susan L.; Canchola, Alison J.; Lee, Marion M.; Reynolds, Peggy; Clarke, Christina A.; Bernstein, Leslie; Stram, Daniel O.

    2009-01-01

    Objective To evaluate the reproducibility and validity of the food-frequency questionnaire (FFQ) used in the California Teachers Study (CTS) cohort and to use this data to quantify the effects of correcting nutrient-breast cancer relative risks for measurement error. Methods 195 CTS cohort members participated in a 10-month dietary validation study that included four 24-hour dietary recalls and pre- and post-study FFQs. Shrout-Fleiss intraclass correlations for reproducibility were computed. Under several standard assumptions concerning the correlations of errors in the FFQs and 24-hour recalls, we calculated energy-adjusted deattenuated Pearson correlations for validity and tested for differences in validity according to a number of demographic and other risk factors. For each nutrient, we compared ot performance of the FFQ versus the 24-hour recalls, estimating the number of days of recalls that give equivalent information about true intake as does a single FFQ.. Finally, the effects of adjustment for measurement error on risk estimates were evaluated in 44,423 postmenopausal cohort members, 1,544 of whom developed breast cancer during seven years of follow-up. Relative risks (RR) and confidence intervals (CI) were calculated using Cox proportional hazards with and without correction for measurement error. Results Reproducibility correlations for the nutrients ranged from 0.60 to 0.87. With a few exceptions, validity correlations were reasonably high (range: 0.55–0.85), including r=0.74 for alcohol. Performance of the FFQ differed by age for percent of calories from fat and by body mass index and hormone therapy use for alcohol consumption. For most nutrients examined, our FFQ is comparable to two to six recalls for each subject in capturing true intake. In the measurement error-adjusted risk analyses, corrected RRs were within 13% of uncorrected values for all nutrients examined except for linoleic acid. For alcohol consumption the corrected RR (per 20g/1000kcal/d) was 1.36 (95% CI: 1.03–1.51) compared to the uncorrected estimate of 1.25 (95% CI: 1.10–1.42). Conclusion The FFQ dietary assessment used in the CTS is reproducible and valid for all nutrients except the unsaturated fatty acids. Correcting relative risk estimates for measurement error resulted in relatively small changes in the associations between the majority of nutrients and the risk of postmenopausal breast cancer. PMID:18256894

  11. Validity of the MAGIC study: sufficient for recommendations?

    PubMed

    Bauer, Katrin; Porzsolt, Franz; Henne-Bruns, Doris

    2013-10-01

    According to the recommendations of the German S3 guideline, perioperative chemotherapy is an integral part of the treatment concept for advanced gastric cancer. The leading trial which examined the effects of perioperative chemotherapy is the MAGIC study. An examination of the validity of this study with a standardized method revealed shortcomings in the six areas: design, protocol, selection of patients, randomization / homogeneity of patient groups, quality of the surgical care and the statistical evaluation. These shortcomings and their influence on the study results are described in this paper to reveal the importance of these effects for discussion in guidelines committees. PMID:24624448

  12. Use and validity of principles of extremum of entropy production in the study of complex systems

    SciTech Connect

    Heitor Reis, A.

    2014-07-15

    It is shown how both the principles of extremum of entropy production, which are often used in the study of complex systems, follow from the maximization of overall system conductivities, under appropriate constraints. In this way, the maximum rate of entropy production (MEP) occurs when all the forces in the system are kept constant. On the other hand, the minimum rate of entropy production (mEP) occurs when all the currents that cross the system are kept constant. A brief discussion on the validity of the application of the mEP and MEP principles in several cases, and in particular to the Earth’s climate is also presented. -- Highlights: •The principles of extremum of entropy production are not first principles. •They result from the maximization of conductivities under appropriate constraints. •The conditions of their validity are set explicitly. •Some long-standing controversies are discussed and clarified.

  13. Electronic conductivity studies on oxyhalide glasses containing TMO

    NASA Astrophysics Data System (ADS)

    Vijayatha, D.; Viswanatha, R.; Sujatha, B.; Narayana Reddy, C.

    2016-05-01

    Microwave-assisted synthesis is cleaner, more economical and much faster than conventional methods. The development of new routes for the synthesis of solid materials is an integral part of material science and technology. The electronic conductivity studies on xPbCl2 - 60 PbO - (40-x) V2O5 (1 ≥ x ≤ 10) glass system has been carried out over a wide range of composition and temperature (300 K to 423 K). X-ray diffraction study confirms the amorphous nature of the samples. The Scanning electron microscopic studies reveal the formation of cluster like morphology in PbCl2 containing glasses. The d.c conductivity exhibits Arrhenius behaviour and increases with V2O5 concentration. Analysis of the results is interpreted in view Austin-Mott's small polaron model of electron transport. Activation energies calculated using regression analysis exhibit composition dependent trend and the variation is explained in view of the structure of lead-vanadate glass.

  14. Online crowdsourcing for efficient rating of speech: A validation study

    PubMed Central

    Byun, Tara McAllister; Halpin, Peter F.; Szeredi, Daniel

    2015-01-01

    Blinded listener ratings are essential for valid assessment of interventions for speech disorders, but collecting these ratings can be time-intensive and costly. This study evaluated the validity of speech ratings obtained through online crowdsourcing, a potentially more efficient approach. 100 words from children with /r/ misarticulation were electronically presented for binary rating by 35 phonetically trained listeners and 205 naïve listeners recruited through the Amazon Mechanical Turk (AMT) crowdsourcing platform. Bootstrapping was used to compare different-sized samples of AMT listeners against a “gold standard” (mode across all trained listeners) and an “industry standard” (mode across bootstrapped samples of 3 trained listeners). There was strong overall agreement between trained and AMT listeners. The “industry standard” level of performance was matched by bootstrapped samples with n = 9 AMT listeners. These results support the hypothesis that valid ratings of speech data can be obtained in an efficient manner through AMT. Researchers in communication disorders could benefit from increased awareness of this method. PMID:25578293

  15. Hopping Conduction and Chemical Structure : a study on Silicon Suboxides

    NASA Astrophysics Data System (ADS)

    van Hapert, J. J.

    2002-06-01

    Using an rf magnetron reactive sputtering technique thin films (<~ 1 mu-m) of amorphous silicon suboxides (a-SiOx, 0 < x < 2) have been deposited. The substrate temperature during deposition remained below 100oC. The films appear rather homogenous in composition (O/Si ratio), with an incorporated fraction of hydrogen and argon atoms of about 2-5 at.%. Taking into account the incorporated argon atoms no large (empty) void fraction has been detected. The films appear composed of Si-Si4-nOn (n= 0, ..., 4) building blocks, with an occurrence of the five individual building blocks in the different compounds generally in agreement with the statistical distribution of randomly dispersed O atoms in a bridging con- figuration between Si atoms. Furthermore, a large density of neutral paramagnetic defects (~ 1021 cm) has been observed. These defects are predominantly associated with silicon dangling bonds (DBs) in a silicon rich environment ( Si-Si3), although in the as deposited compounds with higher O/Si ratio x also Si DBs in more oxygenated environments ( Si-Si2O, Si-SiO2) are observed. Simultaneously, the electrical conductivity of the films indicates a dominant variable range hopping (vrh) mechanism in the compounds, at least up to room temperature. This conduction mechanism is described by a charge transport via thermally assisted tunneling events through localized (defect) states. Since the host network of the defect states in our SiOx films appears rather homogeneous on both macroscopic (mu-m) and microscopic (nm) scale the localized hopping states are expected to be more or less randomly distributed throughout the material. The energy distribution of the corresponding hopping sites is expected to extend over several tenths of an eV, as indicated by measurements on the conductivity around room temperature and supported by a theoretical Density Of States (DOS) model based on a defect-poole model. As a result the vrh conduction process in these SiOx films is adequately described by a system of localized states, randomly distributed in both space and energy. Analytically, it is possible to express the conductivity in such a system qualitatively in terms of the density and localization of the states around the position of the chemical potential. The conductivity appears to depend on the external parameters temperature (T) and electric field (F) and is described differently in different regimes of T and F. In this thesis a more quantitative description of the vrh process is derived numerically using percolation theory. To this purpose calculations on the percolation threshold of the site-to-site impedance in a system of randomly distributed hopping sites were performed. The results appear in qualitative agreement with the analytically derived results. Moreover, the calculations result in a clear quantified description of 1. the temperature dependence of the vrh conduction at low field strengths and 2. the field dependence of the conduction at low field strengths and/or low temperatures. Furthermore, a numerical study on the vrh conduction in a system of non-uniform localized states shows that the conductivity is effectively dominated by the charge transport through a subset of more weakly localized states. Measurements on the temperature and field dependence of the electrical conductivity in the deposited SiOx films appear in good agreement with the theoretical vrh models. Furthermore, quantitative information on the density and localization of the electronic states dominating the macroscopic charge transport is obtained by fitting the measured data with the numerically derived relations. The observed differences in resistivity of the investigated SiOx films appear well explained by a stronger localization of the hopping sites in the more oxygenated environments. Furthermore, it appears that only a small fraction of the neutral paramagnetic states, viz. the more weakly localized states, contributes significantly to the macroscopic charge transport in the vrh conduction process. Both observations are supported by measurements on annealed samples, showing a preferential annihilation of paramagnetic spins in the more oxygenated environments

  16. Conductive Education: Feasibility Study on Developing a National Curriculum Plan for Those Working in Conductive Education in New Zealand.

    ERIC Educational Resources Information Center

    Wagner, Graham A.

    This study sought to determine whether there are national training needs among staff of conductive education programs in New Zealand. Conductive education is a unified system of education for children and adults with a motor disorder whose disability has been caused by damage to the central nervous system. The study, which focuses primarily on…

  17. Sample size determination for disease prevalence studies with partially validated data.

    PubMed

    Qiu, Shi-Fang; Poon, Wai-Yin; Tang, Man-Lai

    2016-02-01

    SummaryDisease prevalence is an important topic in medical research, and its study is based on data that are obtained by classifying subjects according to whether a disease has been contracted. Classification can be conducted with high-cost gold standard tests or low-cost screening tests, but the latter are subject to the misclassification of subjects. As a compromise between the two, many research studies use partially validated datasets in which all data points are classified by fallible tests, and some of the data points are validated in the sense that they are also classified by the completely accurate gold-standard test. In this article, we investigate the determination of sample sizes for disease prevalence studies with partially validated data. We use two approaches. The first is to find sample sizes that can achieve a pre-specified power of a statistical test at a chosen significance level, and the second is to find sample sizes that can control the width of a confidence interval with a pre-specified confidence level. Empirical studies have been conducted to demonstrate the performance of various testing procedures with the proposed sample sizes. The applicability of the proposed methods are illustrated by a real-data example. PMID:22374341

  18. Recommendations for conducting controlled clinical studies of dental restorative materials.

    PubMed

    Hickel, R; Roulet, J-F; Bayne, S; Heintze, S D; Mjör, I A; Peters, M; Rousson, V; Randall, R; Schmalz, G; Tyas, M; Vanherle, G

    2007-03-01

    About 35 years ago, Ryge provided a practical approach to evaluation of clinical performance of restorative materials. This systematic approach was soon universally accepted. While that methodology has served us well, a large number of scientific methodologies and more detailed questions have arisen that require more rigor. Current restorative materials have vastly improved clinical performance and any changes over time are not easily detected by the limited sensitivity of the Ryge criteria in short term clinical investigations. However, the clinical evaluation of restorations not only involves the restorative material per se but also different operative techniques. For instance, a composite resin may show good longevity data when applied in conventional cavities but not in modified operative approaches. Insensitivity, combined with the continually evolving and non-standard investigator modifications of the categories, scales, and reporting methods, has created a body of literature that is extremely difficult to meaningfully interpret. In many cases, the insensitivity of the original Ryge methods is misinterpreted as good clinical performance. While there are many good features of the original system, it is now time to move to a more contemporary one. The current review approaches this challenge in two ways: (1) a proposal for a modern clinical testing protocol for controlled clinical trials, and (2) an in-depth discussion of relevant clinical evaluation parameters, providing 84 references that are primarily related to issues or problems for clinical research trials. Together, these two parts offer a standard for the clinical testing of restorative materials/procedures and provide significant guidance for research teams in the design and conduct of contemporary clinical trials. Part 1 of the review considers the recruitment of subjects, restorations per subject, clinical events, validity versus bias, legal and regulatory aspects, rationales for clinical trial designs, guidelines for design, randomization, number of subjects, characteristics of participants, clinical assessment, standards and calibration, categories for assessment, criteria for evaluation, and supplemental documentation. Part 2 of the review considers categories of assessment for esthetic evaluation, functional assessment, biological responses to restorative materials, and statistical analysis of results. The overall review represents a considerable effort to include a range of clinical research interests over the past years. As part of the recognition of the importance of these suggestions, the review is being published simultaneously in identical form in both the "Journal of Adhesive Dentistry" and the "Clinical Oral Investigations." Additionally an extended abstract will be published in the "International Dental Journal" giving a link to the web full version. This should help to introduce these considerations more quickly to the scientific community. PMID:17262225

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

    SciTech Connect

    Sullivan, R.; Winkelmann, F.

    1998-06-01

    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.

  20. The Bronchiectasis Severity Index. An International Derivation and Validation Study

    PubMed Central

    Goeminne, Pieter; Aliberti, Stefano; McDonnell, Melissa J.; Lonni, Sara; Davidson, John; Poppelwell, Lucy; Salih, Waleed; Pesci, Alberto; Dupont, Lieven J.; Fardon, Thomas C.; De Soyza, Anthony; Hill, Adam T.

    2014-01-01

    Rationale: There are no risk stratification tools for morbidity and mortality in bronchiectasis. Identifying patients at risk of exacerbations, hospital admissions, and mortality is vital for future research. Objectives: This study describes the derivation and validation of the Bronchiectasis Severity Index (BSI). Methods: Derivation of the BSI used data from a prospective cohort study (Edinburgh, UK, 2008–2012) enrolling 608 patients. Cox proportional hazard regression was used to identify independent predictors of mortality and hospitalization over 4-year follow-up. The score was validated in independent cohorts from Dundee, UK (n = 218); Leuven, Belgium (n = 253); Monza, Italy (n = 105); and Newcastle, UK (n = 126). Measurements and Main Results: Independent predictors of future hospitalization were prior hospital admissions, Medical Research Council dyspnea score greater than or equal to 4, FEV1 < 30% predicted, Pseudomonas aeruginosa colonization, colonization with other pathogenic organisms, and three or more lobes involved on high-resolution computed tomography. Independent predictors of mortality were older age, low FEV1, lower body mass index, prior hospitalization, and three or more exacerbations in the year before the study. The derived BSI predicted mortality and hospitalization: area under the receiver operator characteristic curve (AUC) 0.80 (95% confidence interval, 0.74–0.86) for mortality and AUC 0.88 (95% confidence interval, 0.84–0.91) for hospitalization, respectively. There was a clear difference in exacerbation frequency and quality of life using the St. George’s Respiratory Questionnaire between patients classified as low, intermediate, and high risk by the score (P < 0.0001 for all comparisons). In the validation cohorts, the AUC for mortality ranged from 0.81 to 0.84 and for hospitalization from 0.80 to 0.88. Conclusions: The BSI is a useful clinical predictive tool that identifies patients at risk of future mortality, hospitalization, and exacerbations across healthcare systems. PMID:24328736

  1. Visual and dynamic conductivity studies of Laponite RTM hydrogels

    NASA Astrophysics Data System (ADS)

    Henry, Mark L.

    Static hydration of a 3.0 wt. % of LaponiteRTM in deionized (DI) water was investigated at 30oC and 60oC using Electrochemical Impedance Spectrometry (EIS). The results show the transition of the low-density hydrogel to its pure electrostatic repulsion state or Wigner glass within 5 days with a significant reduction in preparation time and without the use of energetic agitation. This was accomplished in real time by placing the fine crystalline powder in a four-probe dynamic conductivity (DC) cell and gently adding DI water under a light vacuum of 17 torr below ambient pressure. Once the hydration began, impedance measurements were taken at regular intervals for several days, while a time-lapse camera recorded the dynamic changes within the DC cell. Combined with the four experimentally determined cell constants and a multi-point calibration curve, this study opens up new insight into the conductive properties of nanocomposite clays during static hydration.

  2. Thermal conductivity and rectification study of restructured Graphene

    NASA Astrophysics Data System (ADS)

    Arora, Anuj

    Electronics' miniaturization, has led to search for better thermal management techniques and discovery of important transport phenomenon. Thermal rectification, directionally preferential heat transport analogous to electrical diode, is one such technique, garnering tremendous interest. Its possibility has been explored through structural asymmetry, introducing a differential phonon density of states in hot and cold regions. As of now, mass and shape asymmetries have been studied, both experimentally and theoretically. However, strict requirements of material length being shorter than phonon mean free path and phonon coherence preservation at surface, makes connecting two materials with different temperature-dependent thermal conductivities, a more natural approach. To avoid resultant thermal boundary resistance and integration complexities, we achieve the affect in single material, by restructuring a region of Graphene by introducing defects. The asymmetry impedes ballistic phonon transport, modulating temperature dependence of thermal conductivity in the two regions. We perform deviational Monte Carlo simulations based on Energy-based formulation to microscopically investigate phonon transport, possibility and optimal conditions for thermal rectification. The proposed method uses phonon properties obtained from first principle, treat phonon-boundary scattering explicitly with properties drawn from Bose-Einstein Distribution.

  3. Low frequency eddy current benchmark study for model validation

    SciTech Connect

    Mooers, R. D.; Boehnlein, T. R.; Cherry, M. R.; Knopp, J. S.; Aldrin, J. C.; Sabbagh, H. A.

    2011-06-23

    This paper presents results of an eddy current model validation study. Precise measurements were made using an impedance analyzer to investigate changes in impedance due to Electrical Discharge Machining (EDM) notches in aluminum plates. Each plate contained one EDM notch at an angle of 0, 10, 20, or 30 degrees from the normal of the plate surface. Measurements were made with the eddy current probe both scanning parallel and perpendicular to the notch length. The experimental response from the vertical and oblique notches will be reported and compared to results from different numerical simulation codes.

  4. Annotations on Mexico's WISC-IV: a validity study.

    PubMed

    Fina, Anthony D; Sánchez-Escobedo, Pedro; Hollingworth, Liz

    2012-01-01

    This project seeks to provide evidence on the internal structure of the Escala Wechsler de Inteligencia para Niños-IV (EWIN-IV; Wechsler, 2007a ) through a confirmatory factor analysis and intercorrelational study. Also provided is information on the adaptation process and other sources of validity evidence in support of the EWIN-IV norms. The standardization data for the EWIN-IV were used for all analyses. The factor loadings and correlational patterns found on the EWIN-IV are comparable to those seen in the American versions of the test. The proposed factor and scoring structure of the EWIN-IV was supported. PMID:23428273

  5. JaCVAM-organized international validation study of the in vivo rodent alkaline comet assay for the detection of genotoxic carcinogens: I. Summary of pre-validation study results.

    PubMed

    Uno, Yoshifumi; Kojima, Hajime; Omori, Takashi; Corvi, Raffaella; Honma, Masamistu; Schechtman, Leonard M; Tice, Raymond R; Burlinson, Brian; Escobar, Patricia A; Kraynak, Andrew R; Nakagawa, Yuzuki; Nakajima, Madoka; Pant, Kamala; Asano, Norihide; Lovell, David; Morita, Takeshi; Ohno, Yasuo; Hayashi, Makoto

    2015-07-01

    The in vivo rodent alkaline comet assay (comet assay) is used internationally to investigate the in vivo genotoxic potential of test chemicals. This assay, however, has not previously been formally validated. The Japanese Center for the Validation of Alternative Methods (JaCVAM), with the cooperation of the U.S. NTP Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM)/the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), the European Centre for the Validation of Alternative Methods (ECVAM), and the Japanese Environmental Mutagen Society/Mammalian Mutagenesis Study Group (JEMS/MMS), organized an international validation study to evaluate the reliability and relevance of the assay for identifying genotoxic carcinogens, using liver and stomach as target organs. The ultimate goal of this validation effort was to establish an Organisation for Economic Co-operation and Development (OECD) test guideline. The purpose of the pre-validation studies (i.e., Phase 1 through 3), conducted in four or five laboratories with extensive comet assay experience, was to optimize the protocol to be used during the definitive validation study. PMID:26212293

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

    PubMed Central

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

    2010-01-01

    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 PMID:21048963

  7. Pooled results from 5 validation studies of dietary self-report instruments using recovery biomarkers for energy and protein intake

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We pooled data from 5 large validation studies of dietary self-report instruments that used recovery biomarkers as references to clarify the measurement properties of food frequency questionnaires (FFQs) and 24-hour recalls. The studies were conducted in widely differing U.S. adult populations from...

  8. Skin Conductance Fear Conditioning Impairments and Aggression: A Longitudinal Study

    PubMed Central

    Gao, Yu; Tuvblad, Catherine; Schell, Anne; Baker, Laura; Raine, Adrian

    2014-01-01

    Autonomic fear conditioning deficits have been linked to child aggression and adult criminal behavior. However, it is unknown if fear conditioning deficits are specific to certain subtypes of aggression, and longitudinal research is rare. In the current study, reactive and proactive aggression were assessed in a sample of males and females when aged 10, 12, 15, and 18 years old. Skin conductance fear conditioning data were collected when they were 18 years old. Individuals who were persistently high on proactive aggression measures had significantly poorer conditioned responses at 18 years old when compared to others. This association was not found for reactive aggression. Consistent with prior literature, findings suggest that persistent antisocial individuals have unique neurobiological characteristics and that poor autonomic fear conditioning is associated with the presence of increased instrumental aggressive behavior. PMID:25174802

  9. First principles study of thermal conductivity cross-over in nanostructured zinc-chalcogenides

    SciTech Connect

    Katre, Ankita; Madsen, Georg K. H.; Togo, Atsushi; Tanaka, Isao

    2015-01-28

    Systematic first principles studies of zinc-chalcogenides have been performed to understand their thermal transport behaviour. We have applied the Boltzmann transport equation in the relaxation time approximation to calculate the thermal conductivity of ZnS, ZnSe, and ZnTe. We find a thermal conductivity cross-over between ZnS and ZnSe at nanostructure sizes around 0.1–0.2 μm and explain this in terms of the different contributions of phonon modes in these materials. We study the effect of nanostructuring using both the diffusive boundary scattering and confined mean free path limit and discuss the variations in the results. Furthermore, we show the strong influence of isotope scattering on the thermal conductivity. The calculated thermal conductivity is found to be strongly dependent on the volume and we explain the observed differences between local density and generalized gradient approximation calculations. We compare further calculated thermal properties, such as the thermal expansion coefficient, to experiment to validate our approach.

  10. Use of wearable technology for performance assessment: a validation study.

    PubMed

    Papi, Enrica; Osei-Kuffour, Denise; Chen, Yen-Ming A; McGregor, Alison H

    2015-07-01

    The prevalence of osteoarthritis is increasing globally but current compliance with rehabilitation remains poor. This study explores whether wearable sensors can be used to provide objective measures of performance with a view to using them as motivators to aid compliance to osteoarthritis rehabilitation. More specifically, the use of a novel attachable wearable sensor integrated into clothing and inertial measurement units located in two different positions, at the waist and thigh pocket, was investigated. Fourteen healthy volunteers were asked to complete exercises adapted from a knee osteoarthritis rehabilitation programme whilst wearing the three sensors including five times sit-to-stand test, treadmill walking at slow, preferred and fast speeds. The performances of the three sensors were validated against a motion capture system and an instrumented treadmill. The systems showed a high correlation (r(2) > 0.7) and agreement (mean difference range: -0.02-0.03 m, 0.005-0.68 s) with gold standards. The novel attachable wearable sensor was able to monitor exercise tasks as well as the inertial measurement units (ICC > 0.95). Results also suggested that a functional placement (e.g., situated in a pocket) is a valid position for performance monitoring. This study shows the potential use of wearable technologies for assessing subject performance during exercise and suggests functional solutions to enhance acceptance. PMID:25937613

  11. Use of wearable technology for performance assessment: A validation study

    PubMed Central

    Papi, Enrica; Osei-Kuffour, Denise; Chen, Yen-Ming A; McGregor, Alison H

    2015-01-01

    The prevalence of osteoarthritis is increasing globally but current compliance with rehabilitation remains poor. This study explores whether wearable sensors can be used to provide objective measures of performance with a view to using them as motivators to aid compliance to osteoarthritis rehabilitation. More specifically, the use of a novel attachable wearable sensor integrated into clothing and inertial measurement units located in two different positions, at the waist and thigh pocket, was investigated. Fourteen healthy volunteers were asked to complete exercises adapted from a knee osteoarthritis rehabilitation programme whilst wearing the three sensors including five times sit-to-stand test, treadmill walking at slow, preferred and fast speeds. The performances of the three sensors were validated against a motion capture system and an instrumented treadmill. The systems showed a high correlation (r2 > 0.7) and agreement (mean difference range: −0.02–0.03 m, 0.005–0.68 s) with gold standards. The novel attachable wearable sensor was able to monitor exercise tasks as well as the inertial measurement units (ICC > 0.95). Results also suggested that a functional placement (e.g., situated in a pocket) is a valid position for performance monitoring. This study shows the potential use of wearable technologies for assessing subject performance during exercise and suggests functional solutions to enhance acceptance. PMID:25937613

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

    SciTech Connect

    Smolen, G.R.; Yamana, H. )

    1988-01-01

    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.

  13. Photoluminescence and conductivity studies of anthracene-functionalized ruthenium nanoparticles.

    PubMed

    Chen, Wei; Pradhan, Sulolit; Chen, Shaowei

    2011-05-01

    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 π 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

  14. Mouse ECG findings in aging, with conduction system affecting drugs and in cardiac pathologies: Development and validation of ECG analysis algorithm in mice.

    PubMed

    Merentie, Mari; Lipponen, Jukka A; Hedman, Marja; Hedman, Antti; Hartikainen, Juha; Huusko, Jenni; Lottonen-Raikaslehto, Line; Parviainen, Viktor; Laidinen, Svetlana; Karjalainen, Pasi A; Ylä-Herttuala, Seppo

    2015-12-01

    Mouse models are extremely important in studying cardiac pathologies and related electrophysiology, but very few mouse ECG analysis programs are readily available. Therefore, a mouse ECG analysis algorithm was developed and validated. Surface ECG (lead II) was acquired during transthoracic echocardiography from C57Bl/6J mice under isoflurane anesthesia. The effect of aging was studied in young (2-3 months), middle-aged (14 months) and old (20-24 months) mice. The ECG changes associated with pharmacological interventions and common cardiac pathologies, that is, acute myocardial infarction (AMI) and progressive left ventricular hypertrophy (LVH), were studied. The ECG raw data were analyzed with an in-house ECG analysis program, modified specially for mouse ECG. Aging led to increases in P-wave duration, atrioventricular conduction time (PQ interval), and intraventricular conduction time (QRS complex width), while the R-wave amplitude decreased. In addition, the prevalence of arrhythmias increased during aging. Anticholinergic atropine shortened PQ time, and beta blocker metoprolol and calcium-channel blocker verapamil increased PQ interval and decreased heart rate. The ECG changes after AMI included early JT elevation, development of Q waves, decreased R-wave amplitude, and later changes in JT/T segment. In progressive LVH model, QRS complex width was increased at 2 and especially 4 weeks timepoint, and also repolarization abnormalities were seen. Aging, drugs, AMI, and LVH led to similar ECG changes in mice as seen in humans, which could be reliably detected with this new algorithm. The developed method will be very useful for studies on cardiovascular diseases in mice. PMID:26660552

  15. [French validation study of the levels of emotional awareness scale].

    PubMed

    Bydlowski, S; Corcos, M; Paterniti, S; Guilbaud, O; Jeammet, P; Consoli, S M

    2002-01-01

    According to a thesis based on the idea of an influence of cognitions in the structuring of internal reality, emotional awareness, ie the capacity of representing your own emotional experience and that of others, is a cognitive process that goes into maturation. Defining this concept, Lane and Schwartz present a cognitivo-developmental model in five stages of the processes of symbolization, accounting for the differences in levels of emotional awareness observed in individuals. The organization of these cognitive processes would thus be structured in well differentiated stages, in which the development of the emotions would be inseparable from the development of ego and of the relation to others. These authors focus on the capacity of representing in a conscious way the emotional experience and consider that verbal representations used to describe the contents of what is experience constitute a good reflection of the organization structural of the emotional awareness. Therefore, they worked out an instrument of evaluation: the Levels of Emotional Awareness Scale (LEAS), which measures the capacity to describe your own emotional experience and the one you allow to others, in an emotional situation. The system of quotation of this scale is based on the analysis of the verbal contents of the provided answers, in direct reference to the authors' theory of the levels of differentiation and integration of the emotional experience. It is therefore an empirical measurement which is centered specifically on the structural organization of the emotional experience. The various studies of validation of this instrument show that it presents solid metrological properties. This work presents the validation of the French version of Lane and Schwartz's LEAS. Validity and fidelity were studied in a group of 121 healthy subjects. This setting is part of a larger clinical evaluation, also including a collection of socio-demographic and clinical data, and other instruments of self-evaluation (Beck Depression Inventory, BDI, Hospital Anxiety and Depression Scale, HAD, and Toronto Alexithymia Scale, TAS). The face validity appears correct: the questionnaire was well accepted and seemed easy to complete. A principal components analysis of the correlation matrix of the set of items was used as the method of extraction of the various factors and made it possible to confirm the unidimensionality of the instrument. The number of factors to be retained was given according to Kaiser and Cattell criteria. The internal consistency was evaluated through computation of the Cronbach coefficient, whose value is 0.75 for the scale's global score. The confidence interval of the margin of error of LEAS scores was also measured; for the global score it is IC=[m 6.1]. The measure given by this rating scale may therefore be considered sufficiently accurate, since this interval is weak. A study of the frequency of quotation of each item of the instrument was carried out, in order to check the homogeneity and the uniformity of quotations, as well as a diagram of distribution of the score, showing that it follows a law which is close to a normal law. The concurrent validity could only be studied via the similar concept of alexithymia, measured with the TAS, for there is not other instrument validated in French evaluating the levels of emotional awareness, and these two instruments seem to measure different notions, because none of the correlations between the scores of these two questionnaires are significant. Concerning discriminant validity, the Pearson correlation coefficients between the global score for the LEAS, the BDI score and the HAD sub-scores for depression and anxiety were measured; it is clear that the level of emotional awareness is independent from negative affects. Furthermore, the study of the reliability made it possible to highlight excellent intra-class correlation coefficients (r=0.993). The French version of the Levels of Emotional Awareness Scale thus appears to be valid and accurate and should allow the study of levels of emotional awareness on psychopathology. It is about an easily acceptable and simple questionnaire of use in varied clinical circumstances. PMID:12232540

  16. Pilot In-Trail Procedure Validation Simulation Study

    NASA Technical Reports Server (NTRS)

    Bussink, Frank J. L.; Murdoch, Jennifer L.; Chamberlain, James P.; Chartrand, Ryan; Jones, Kenneth M.

    2008-01-01

    A Human-In-The-Loop experiment was conducted at the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) to investigate the viability of the In-Trail Procedure (ITP) concept from a flight crew perspective, by placing participating airline pilots in a simulated oceanic flight environment. The test subject pilots used new onboard avionics equipment that provided improved information about nearby traffic and enabled them, when specific criteria were met, to request an ITP flight level change referencing one or two nearby aircraft that might otherwise block the flight level change. The subject pilots subjective assessments of ITP validity and acceptability were measured via questionnaires and discussions, and their objective performance in appropriately selecting, requesting, and performing ITP flight level changes was evaluated for each simulated flight scenario. Objective performance and subjective workload assessment data from the experiment s test conditions were analyzed for statistical and operational significance and are reported in the paper. Based on these results, suggestions are made to further improve the ITP.

  17. Cross-cultural adaptation, evaluation and validation of the Spouse Response Inventory: a study protocol

    PubMed Central

    Kaiser, Ulrike; Steinmetz, Dorit; Scharnagel, Rüdiger; Jensen, Mark P; Balck, Friedrich; Sabatowski, Rainer

    2014-01-01

    Introduction Since the response of spouses has been proven to be an important reinforcement of pain behaviour and disability it has been addressed in research and therapy. Fordyce suggested pain behaviour and well behaviour be considered in explaining suffering in chronic pain patients. Among existing instruments concerning spouse's responses the aspect of well behaviour has not been examined so far. The SRI (Spouse Response Inventory) tries to consider pain behaviour and well behaviour and appears to be acceptable because of its brevity and close proximity to daily language. The aim of the study is the translation into German, followed by evaluation and validation, of the SRI on a German sample of patients with chronic pain. Methods and analyses The study is comprehensively designed: initially, the focus will lie on the translation of the instrument following the guidelines for cross-cultural translation and adaptation and evaluation of the German version according to the source study. Subsequently, a validation referring to predictive, incremental and construct validation will be conducted using instruments based on similar or close but different constructs. Evaluation of the resulting SRI-G (SRI-German) will be conducted on a sample of at least 30 patients with chronic pain attending a comprehensive pain centre. For validation at least 120 patients with chronic headache, back pain, cancer related pain and somatoform pain disorder shall be included, for a total of 480 patients. Separate analyses according to specific pain diagnoses will be performed to ensure psychometric property, interpretability and control of diagnosis of specific limitations. Analyses will include comprehensive investigation of psychometric property of the scale by hierarchical regression analyses, correlation analyses, multivariate analysis of variance and exploratory factor analyses (SPSS). Ethics The study protocol was approved by the Ethics Committee of the University of Dresden (EK 335 122008) based on the Helsinki declaration. PMID:25763793

  18. The Fast Scattering Code (FSC): Validation Studies and Program Guidelines

    NASA Technical Reports Server (NTRS)

    Tinetti, Ana F.; Dunn, Mark H.

    2011-01-01

    The Fast Scattering Code (FSC) is a frequency domain noise prediction program developed at the NASA Langley Research Center (LaRC) to simulate the acoustic field produced by the interaction of known, time harmonic incident sound with bodies of arbitrary shape and surface impedance immersed in a potential flow. The code uses the equivalent source method (ESM) to solve an exterior 3-D Helmholtz boundary value problem (BVP) by expanding the scattered acoustic pressure field into a series of point sources distributed on a fictitious surface placed inside the actual scatterer. This work provides additional code validation studies and illustrates the range of code parameters that produce accurate results with minimal computational costs. Systematic noise prediction studies are presented in which monopole generated incident sound is scattered by simple geometric shapes - spheres (acoustically hard and soft surfaces), oblate spheroids, flat disk, and flat plates with various edge topologies. Comparisons between FSC simulations and analytical results and experimental data are presented.

  19. A protocol for conducting rainfall simulation to study soil runoff.

    PubMed

    Kibet, Leonard C; Saporito, Louis S; Allen, Arthur L; May, Eric B; Kleinman, Peter J A; Hashem, Fawzy M; Bryant, Ray B

    2014-01-01

    Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial urea, a common form of nitrogen (N) fertilizer, following a rainfall event that occurs within 24 hr after fertilizer application. Although urea is assumed to be readily hydrolyzed to ammonium and therefore not often available for transport, recent studies suggest that urea can be transported from agricultural soils to coastal waters where it is implicated in harmful algal blooms. A rainfall simulator was used to apply a consistent rate of uniform rainfall across packed soil boxes that had been prewetted to different soil moisture contents. By controlling rainfall and soil physical characteristics, the effects of antecedent soil moisture on urea loss were isolated. Wetter soils exhibited shorter time from rainfall initiation to runoff initiation, greater total volume of runoff, higher urea concentrations in runoff, and greater mass loadings of urea in runoff. These results also demonstrate the importance of controlling for antecedent soil moisture content in studies designed to isolate other variables, such as soil physical or chemical characteristics, slope, soil cover, management, or rainfall characteristics. Because rainfall simulators are designed to deliver raindrops of similar size and velocity as natural rainfall, studies conducted under a standardized protocol can yield valuable data that, in turn, can be used to develop models for predicting the fate and transport of pollutants in runoff. PMID:24748061

  20. A Protocol for Conducting Rainfall Simulation to Study Soil Runoff

    PubMed Central

    Kibet, Leonard C.; Saporito, Louis S.; Allen, Arthur L.; May, Eric B.; Kleinman, Peter J. A.; Hashem, Fawzy M.; Bryant, Ray B.

    2014-01-01

    Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial urea, a common form of nitrogen (N) fertilizer, following a rainfall event that occurs within 24 hr after fertilizer application. Although urea is assumed to be readily hydrolyzed to ammonium and therefore not often available for transport, recent studies suggest that urea can be transported from agricultural soils to coastal waters where it is implicated in harmful algal blooms. A rainfall simulator was used to apply a consistent rate of uniform rainfall across packed soil boxes that had been prewetted to different soil moisture contents. By controlling rainfall and soil physical characteristics, the effects of antecedent soil moisture on urea loss were isolated. Wetter soils exhibited shorter time from rainfall initiation to runoff initiation, greater total volume of runoff, higher urea concentrations in runoff, and greater mass loadings of urea in runoff. These results also demonstrate the importance of controlling for antecedent soil moisture content in studies designed to isolate other variables, such as soil physical or chemical characteristics, slope, soil cover, management, or rainfall characteristics. Because rainfall simulators are designed to deliver raindrops of similar size and velocity as natural rainfall, studies conducted under a standardized protocol can yield valuable data that, in turn, can be used to develop models for predicting the fate and transport of pollutants in runoff. PMID:24748061

  1. The Adolescent Depression Rating Scale (ADRS): a validation study

    PubMed Central

    Revah-Levy, Anne; Birmaher, Boris; Gasquet, Isabelle; Falissard, Bruno

    2007-01-01

    Background To examine the psychometric properties of the Adolescent Depression Rating Scale (ADRS), a new measure was specifically designed to evaluate adolescent depression. Methods The 11-item clinician-report and 44-item self-report versions of the ADRS were developed from a qualitative phase involving interviews of experts and adolescents. These two instruments were then administered to 402 French speaking adolescents with and without depressive disorders. Item distribution, internal consistency, convergent validity, discriminant validity and factorial structure were assessed. Results After reduction procedures, a 10-item clinician version and a 10-item self-report version were obtained. The ADRS demonstrated good internal consistency (alpha Cronbach coefficient >.70). It also discriminated better between adolescents with and without depression than the Hamilton Depressive Rating Scale and the Beck Depression Inventory (BDI-13). Conclusion The ADRS is a useful, short, clinician-report and self-report scale to evaluate adolescent depression. Further studies to replicate our findings and evaluate ADRS sensitivity to effects of treatment and psychometric properties in populations of adolescents with several psychiatric disorders are warranted. PMID:17222346

  2. Genome-wide association study of conduct disorder symptomatology

    PubMed Central

    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

    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. PMID:20585324

  3. A validation study of a stochastic model of human interaction

    NASA Astrophysics Data System (ADS)

    Burchfield, Mitchel Talmadge

    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.

  4. Photoluminescence and conductivity studies of anthracene-functionalized ruthenium nanoparticles

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Pradhan, Sulolit; Chen, Shaowei

    2011-05-01

    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 1H 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 z.dbd C π 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.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 1H 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 z.dbd C π 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. Electronic supplementary information (ESI) available: Deconvolution of fluorescence spectra of monomeric 9-vinylanthracene and Ru z.dbd VAN nanoparticles, and Arrhenius plots of the Ru z.dbd C8 and Ru z.dbd VAN nanoparticle electronic conductivity. See DOI: 10.1039/c1nr10158g

  5. Studying conduction-electron/interface interactions using transverse electron focusing

    NASA Astrophysics Data System (ADS)

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

    1999-10-01

    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.

  6. New York State TrueAllele® Casework Validation Study*

    PubMed Central

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

    2013-01-01

    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

  7. Can large surveys conducted on highly selected populations provide valid information on the epidemiology of common health conditions? An analysis of UK Biobank data on musculoskeletal pain

    PubMed Central

    Macfarlane, Gary J; Beasley, Marcus; Smith, Blair H; Jones, Gareth T; Macfarlane, Tatiana V

    2015-01-01

    Introduction: Biobank-type studies are typically large but have very low participation rates. It has been suggested that these studies may provide biased estimates of prevalence but are likely to provide valid estimates of association. We test these hypotheses using data collected on pain in a large Biobank study in the United Kingdom. Methods: UK Biobank recruited 503,325 persons aged 40–69 years (participation rate 5.5%). Participants completed questionnaires, including pain, lifestyle and environment factors. As a comparison, we used both a large population study of pain (MUSICIAN: n = 8847, aged: 40–69 years) conducted 2008–2009 and the National Child Development study (NCDS) which recruited all persons in Great Britain born during one week of 1958 and followed them up at age 44 years (n = 9377). Results: ‘Any pain’ (UK Biobank 61.0%; MUSICIAN 63.9%), chronic pain (42.9%, 52.2%) and site-specific musculoskeletal pain (back 26.2%, 29.7%; shoulder/neck 23.3%, 25.3%) were generally similar in UK Biobank and MUSICIAN. The prevalence of chronic pain and most regional musculoskeletal pains in UK Biobank were all within 2% of that in NCDS. Conclusion: UK Biobank has provided estimates of the prevalence of pain which are similar to those from previous large-scale studies, although a formal comparison of the estimates cannot be made. It has also confirmed known associations with the reporting of pain. Despite its very low participation rate, such a study provides the opportunity to investigate novel exposure–pain relationships and investigate rarer exposures and characteristics to further our knowledge of the epidemiology of pain. PMID:26526341

  8. A Cross-Validation Study of the Kirton Adaption-Innovation Inventory in Three Research and Development Organizations.

    ERIC Educational Resources Information Center

    Keller, Robert T.; Holland, Winford E.

    1979-01-01

    A cross-validation study of the Kirton Adaption-Innovation Inventory (KAI) was conducted with 256 professional employees from three applied research and development organizations. The KAI correlated well with both direct and indirect measures of innovativeness in all three organizations. (Author/MH)

  9. An Aptitude-Test Battery for Court-Reporter Training: Initial Results of a Longitudinal Validation Study.

    ERIC Educational Resources Information Center

    Jacobsen, Linda S.; Borchardt, Gordon C.

    In order to identify a battery of aptitude tests which could adequately predict the success of applicants to its court-reporting program, MacCormac Junior College contracted with Science Research Associates in Fall 1976 to conduct a longitudinal validation study of court-reporting aptitude measures. Eight tests were administered to each…

  10. A Known Group Analysis Validity Study of the Vanderbilt Assessment of Leadership in Education in US Elementary and Secondary Schools

    ERIC Educational Resources Information Center

    Covay Minor, Elizabeth; Porter, Andrew C.; Murphy, Joseph; Goldring, Ellen B.; Cravens, Xiu; Elloitt, Stephen N.

    2014-01-01

    The Vanderbilt Assessment of Leadership in Education (VAL-ED) provides educators with a tool for principal evaluation based on principal, teacher, and supervisor reports of principals' learning-centered leadership. In this study, we conduct a known group analysis as part of a larger argument for the validity of the VAL-ED in US elementary and…

  11. ACCURACY OF DIETARY RECALL USING THE USDA 5-STEP MULTIPLE PASS METHOD IN MEN: AN OBSERVATIONAL VALIDATION STUDY.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This 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 5-Step Multiple-Pass Method for dietary recall. This was a Cross-sectional analysis of actual and recalled intake of food du...

  12. Highly anisotropic thermal conductivity of arsenene: An ab initio study

    NASA Astrophysics Data System (ADS)

    Zeraati, Majid; Vaez Allaei, S. Mehdi; Abdolhosseini Sarsari, I.; Pourfath, Mahdi; Donadio, Davide

    2016-02-01

    Elemental two-dimensional (2D) materials exhibit intriguing heat transport and phononic properties. Here we have investigated the lattice thermal conductivity of newly proposed arsenene, the 2D honeycomb structure of arsenic, using ab initio calculations. Solving the Boltzmann transport equation for phonons, we predict a highly anisotropic thermal conductivity of 30.4 and 7.8 W/mK along the zigzag and armchair directions, respectively, at room temperature. Our calculations reveal that phonons with mean free paths between 20 nm and 1 μ m provide the main contribution to the large thermal conductivity in the zigzag direction; mean free paths of phonons contributing to heat transport in the armchair directions range between 20 and 100 nm. The obtained anisotropic thermal conductivity and feasibility of synthesis, in addition to high electron mobility reported elsewhere, make arsenene a promising material for nanoelectronic applications and thermal management.

  13. Comparative Study of the Thermal Conductivity of Solid Biomass Fuels

    PubMed Central

    2016-01-01

    The thermal conductivity of solid biomass fuels is useful information in the investigation of biomass combustion behavior and the development of modeling especially in the context of large scale power generation. There are little published data on the thermal conductivity of certain types of biomass such as wheat straw, miscanthus, and torrefied woods. Much published data on wood is in the context of bulk materials. A method for determining the thermal conductivities of small particles of biomass fuels has been developed using a custom built test apparatus. Fourteen different samples of various solid biomass fuel were processed to form a homogenized pellet for analysis. The thermal conductivities of the pelletized materials were determined and compared against each other and to existing data. PMID:27041819

  14. [Study on the conductivity properties of lightning channel by spectroscopy].

    PubMed

    Wang, Xue-Juan; Yuan, Ping; Cen, Jian-Yong; Wang, Jie; Zhang, Ting-Long

    2013-12-01

    Combining the spectra of cloud-to-ground lightning return obtained by a slit-less spectrograph with the transport theory of air plasma, the electrical conductivity in one discharge channel was calculated with different methods. The results show that the conductivity of the lightning channel core is of the order of 10(4) S m-1; the conductivity goes down with the increase in the channel height in the same channel; the contributions of the collisions between electron and first or second degree ionized atoms, and electron-electron as well as ion-ion collisions to the electrical conductivity of the lightning channel core can not be neglected; the collision integrals method is more reasonable for calculating the conductivity of the lightning channel core. Based on the conductivity, the discharge current was estimated and compared with the peak current of every return stroke, and the results are in the reasonable range, further, the correlation between the channel temperature and the discharge characteristics is discussed, which provides a practical way for this aspect. PMID:24611368

  15. Heat conduction in graphene: experimental study and theoretical interpretation

    NASA Astrophysics Data System (ADS)

    Ghosh, S.; Nika, D. L.; Pokatilov, E. P.; Balandin, A. A.

    2009-09-01

    We review the results of our experimental investigation of heat conduction in suspended graphene and offer a theoretical interpretation of its extremely high thermal conductivity. The direct measurements of the thermal conductivity of graphene were performed using a non-contact optical technique and special calibration procedure with bulk graphite. The measured values were in the range of ~3000-5300 W mK-1 near room temperature and depended on the lateral dimensions of graphene flakes. We explain the enhanced thermal conductivity of graphene as compared to that of bulk graphite basal planes by the two-dimensional nature of heat conduction in graphene over the whole range of phonon frequencies. Our calculations show that the intrinsic Umklapp-limited thermal conductivity of graphene grows with the increasing dimensions of graphene flakes and can exceed that of bulk graphite when the flake size is on the order of a few micrometers. The detailed theory, which includes the phonon-mode-dependent Gruneisen parameter and takes into account phonon scattering on graphene edges and point defects, gives numerical results that are in excellent agreement with the measurements for suspended graphene. Superior thermal properties of graphene are beneficial for all proposed graphene device applications.

  16. 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 ...

  17. A comprehensive study on maxillofacial trauma conducted in Yamunanagar, India

    PubMed Central

    Bali, Rishi; Sharma, Parveen; Garg, Amandeep; Dhillon, Guneet

    2013-01-01

    Abstract: Background: The Department of Oral and Maxillofacial Surgery, D.A.V [C] Dental College and Hospital, Yamuna Nagar, Haryana, India conducted a study on patients with maxillofacial fractures in a time span of seven years (2003-2010). The purpose of this study was to evaluate their aetiology, incidence, patterns and different modalities employed for management. Methods: In this study, 740 patients with 1054 fractures were evaluated clinically and radiographically, based on which closed reduction and open reduction was undertaken. Review of patient records included: Age, sex, time, mechanism and etiology of injury, history of bleeding, unconsciousness and prior first aid, type of vehicle and use of preventive measures, type of fracture and treatment modalities. Results: Road traffic accidents accounted for highest number of fractures predominantly occurring in the age group of 21-30 years (38.3%)1,2. Males incurred more fractures with a male female ratio of 4.2: 1.Mandible was the most commonly fractured bone with parasymphysis being the commonest affected site.76.66% patients had associated head injury and 15.68 % had history of unconsciousness. Open reduction and internal fixation was the preferred modality for mandible whereas the mid face fractures were treated more often by closed methods. Conclusions: Injuries occurred more commonly in 20 – 40 age range with road traffic accident being the major etiological factor. Majority of the patients were driving two wheelers and most were under the effect of alcohol. Most of the injuries occurred during night and road traffic accidents (71.89%) were found to be the major etiological factor. Out of 532 road traffic accidents, 490 patients (66.2%) were on two wheelers, among whom 49(10%) were wearing helmet. In the mandible, fractures occurred most commonly in the parasymphyseal region (224, 30.2%), and out of the 314 fractures of the middle third showed, 155 (49.4%) ZMC. OPG was the most commonly advised X-ray. With regard to treatment modalities, 36.8% of all the mandibular fractures (740) were treated by closed reduction, 62.6% were treated using open reduction and 0.5% was under observation only. PMID:23594725

  18. A validation study of elementary science ISTEP+ scores

    NASA Astrophysics Data System (ADS)

    Simonelli, Glenn

    The Indiana Statewide Testing for Educational Progress-Plus (ISTEP+) was designed to assess student mastery of key educational goals. The 5th grade ISTEP+ Science Test (5-GIST) is part of the ISTEP+ testing regime. The Indiana Academic Standards were developed to guide instruction in the state, and questions on the ISTEP+ were aligned with these standards. Since its inception, the use of the ISTEP+ exam has been changed to comply with the dictates of both Indiana Public Law 221 and the national No Child Left Behind act. With these modifications, the purpose of the tests has shifted from assessment of individual student academic progress to evaluation of the quality of the educational institution administering the tests. The validity of this use has never been established. The purpose of this study is to assess the validity of the 5-GIST as an instrument for assessing and forming judgments about the quality of science instruction in a particular school. ISTEP+ scores of 2 cohorts of students in a Midwestern school district were converted into Z-scores and tracked from 3rd to 5th grade. A regression line was established to account for the general aptitude and the socio-economic status (SES) of the students. Examining the residuals of the 5-GIST scores revealed that between 57% and 60% of the variance in the scores can be attributed to the general aptitude and SES of the students, leaving between 40% and 43% that can be interpreted as reflecting the effect of the school on student learning.

  19. 40 CFR 152.92 - Submission of a new valid study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Submission of a new valid study. 152... Submitters' Rights 152.92 Submission of a new valid study. An applicant may demonstrate compliance for a data requirement by submitting a valid study that has not previously been submitted to the Agency....

  20. Study of new proton conducting glasses for fuel cells

    NASA Astrophysics Data System (ADS)

    Tiple, S. R.; Deshpande, V. K.

    2015-08-01

    The glasses in the series (35-x) BaO:65 P2O5:x (NH4)2SO4 are synthesized and characterized by Tg, CTE, density and electrical conductivity measurements. The decrease in density and Tg is observed with addition of (NH4)2SO4. The increase in CTE compliments the observed variation in Tg. The protonic conductivity increases with addition of (NH4)2SO4 up to 7.5 mol% and decreases beyond this composition. The increase in the ratio of O/P, which in turn, creates more non-bridging oxygens, enhances the conductivity. Further, sulfur is mainly incorporated in sulfophosphate glasses as isolated SO42- group which also results in increase in conductivity. The glass with maximum conductivity [7.5(NH4)2SO4:27.5BaO:65 P2O5] is used to fabricate a fuel cell. It gives the power density of 12.43 μW/cm2. The power density of the fuel cell in the present work at room temperature is higher than that reported in literature at 473 K. The fuel cell has a potential of giving higher power density at higher temperature of 423 K.

  1. Electrical Characterization and Morphological Studies of Conducting Polymer Nanofibers

    NASA Technical Reports Server (NTRS)

    Pinto, N. J.; Zhou, Y. X.; Freitag, M.; Johnson, A. T.; MacDiarmid, A. G.; Mueller, C. H.; Theofylaktos, N.; Robinson, D. C.; Miranda, F. A.

    2003-01-01

    Doped polyaniline blended with poly(ethylene oxide) has been electrospun in air to give fibers with diameters in the range 3 nm 200 nm. These fibers were captured on wafers of degenerately doped Si/SiO2 by placing the wafer in the path of the fiber jet formed during the electrospinning process. Individual fibers were contacted using shadow mask evaporation and were also captured on prepatterned wafers. Fibers having diameters greater than 100 nm show a slight increase in the conductivity as compared to the bulk film, while fibers with diameters less than 30 nm had lower conductivity than the bulk. Data on Scanning Conductance Microscopy along the length of individual fibers will be presented. For fibers where the diameter was not uniform, we found that below a certain diameter ( approx.15 nm) the fiber was less conducting as compared to thicker diameter fibers. Dependence of the fiber conductivity on a gate bias is underway and these results will also be presented.

  2. A Construct Validation Study of the Counseling Expectation Inventory.

    ERIC Educational Resources Information Center

    Turner, Carol J.; Schwartzbach, Helene

    1983-01-01

    Evaluated the Counseling Expectation Inventory (CEI), designed to measure prognostic expectation. Participants were clients (N=200) and counselors (N=19) from six college counseling centers. Results suggested convergent and discriminant validity but evidence for construct validity was weak. Improvements in the CEI are needed before it's used in

  3. A Delphi Study and Initial Validation of Counselor Supervision Competencies

    ERIC Educational Resources Information Center

    Neuer Colburn, Anita A.; Grothaus, Tim; Hays, Danica G.; Milliken, Tammi

    2016-01-01

    The authors addressed the lack of supervision training standards for doctoral counseling graduates by developing and validating an initial list of supervision competencies. They used content analysis, Delphi polling, and content validity methods to generate a list, vetted by 2 different panels of supervision experts, of 33 competencies grouped…

  4. The Coopersmith Self-Esteem Inventory: A Construct Validation Study.

    ERIC Educational Resources Information Center

    Johnson, Brian W.

    1983-01-01

    Regression analyses indicated that the Coopersmith Self-Esteem Inventory has convergent validity with regard to the Piers-Harris Children's Self-Concept Scale and the Coopersmith Behavioral Academic Assessment Scale, has discriminant validity with regard to the Children's Social Desirability Scale, is sensitive to differences in achievement level,…

  5. A Delphi Study and Initial Validation of Counselor Supervision Competencies

    ERIC Educational Resources Information Center

    Neuer Colburn, Anita A.; Grothaus, Tim; Hays, Danica G.; Milliken, Tammi

    2016-01-01

    The authors addressed the lack of supervision training standards for doctoral counseling graduates by developing and validating an initial list of supervision competencies. They used content analysis, Delphi polling, and content validity methods to generate a list, vetted by 2 different panels of supervision experts, of 33 competencies grouped

  6. Verification and Validation Studies for the LAVA CFD Solver

    NASA Technical Reports Server (NTRS)

    Moini-Yekta, Shayan; Barad, Michael F; Sozer, Emre; Brehm, Christoph; Housman, Jeffrey A.; Kiris, Cetin C.

    2013-01-01

    The verification and validation of the Launch Ascent and Vehicle Aerodynamics (LAVA) computational fluid dynamics (CFD) solver is presented. A modern strategy for verification and validation is described incorporating verification tests, validation benchmarks, continuous integration and version control methods for automated testing in a collaborative development environment. The purpose of the approach is to integrate the verification and validation process into the development of the solver and improve productivity. This paper uses the Method of Manufactured Solutions (MMS) for the verification of 2D Euler equations, 3D Navier-Stokes equations as well as turbulence models. A method for systematic refinement of unstructured grids is also presented. Verification using inviscid vortex propagation and flow over a flat plate is highlighted. Simulation results using laminar and turbulent flow past a NACA 0012 airfoil and ONERA M6 wing are validated against experimental and numerical data.

  7. Portuguese validation of the Internet Addiction Test: An empirical study

    PubMed Central

    PONTES, HALLEY M.; PATRÃO, IVONE M.; GRIFFITHS, MARK D.

    2014-01-01

    Background and aims: Research into Internet addiction (IA) has increased greatly over the last decade. Despite its various definitions and general lack of consensus regarding its conceptualisation amongst researchers, instruments for measuring this phenomenon have proliferated in a number of countries. There has been little research on IA in Portugal and this may be partly due to the absence of standardised measurement tools for assessing IA. Methods: This study attempted to address this issue by adapting a Portuguese version of the Internet Addiction Test (IAT) via a translation-back translation process and Confirmatory Factor Analysis in a sample of 593 Portuguese students that completed a Portuguese version of the IAT along with questions related to socio-demographic variables. Results: The findings suggested that the IAT appears to be a valid and reliable instrument for measuring IA among Portuguese young adults as demonstrated by its satisfactory psychometric properties. However, the present findings also suggest the need to reword and update some of the IAT’s items. Prevalence of IA found in the sample was 1.2% and is discussed alongside findings relating to socio-demographic correlates. Limitations and implications of the present study are also discussed. Conclusions: The present study calls for a reflection of the IAT while also contributing to a better understanding of the basic aspects of IA in the Portuguese community since many health practitioners are starting to realise that Internet use may pose a risk for some individuals. PMID:25215221

  8. Laser flash thermal conductivity studies of porous metal fiber materials

    NASA Astrophysics Data System (ADS)

    Golombok, M.; Shirvill, L. C.

    1988-03-01

    A laser-flash technique (with 30-ms pulses of a 1.8-kW CO2 IR laser) is used to measure thermal conductivity in Bekitherm (Johnson and Johnson, 1986), a porous material produced by sintering 22-micron-diameter fibers of refractory steel and intended for application to surface-combustion gas burners. The experimental setup is described, and the data are presented in graphs and shown to be in good agreement with the results of numerical simulations based on an ordered model of the material. The conductivity perpendicular to the lay fibers is found to be 8.8 times smaller than that within the layers and 73 times smaller than that of the solid metal. Heat transfer through the pores is found to significantly enhance the thermal conductivity at high temperatures.

  9. Conductivity and Structural Studies of Magnesium Based Solid Electrolytes

    NASA Astrophysics Data System (ADS)

    Ahmad, A. Hanom; Ghani, F. S. Abdul

    2009-06-01

    In this investigation, magnesium based solid electrolyte was prepared via ball milling method. MgI2-Mg3(PO4)2 were mixed in varied compositions and ball milled for 1 hour. The milled mixtures were pelletized and the conductivity was measured using the Impedance Spectroscopy (IS) method. The MgI2-Mg3(PO4)2 pellet containing 30% wt of MgI2 showed maximum conductivity of 7.00×10-4 S/cm. Further structural characterization and analysis of these Mg2+ ion conductors were carried out by using X-ray diffraction (XRD), Fourier Transform Infra-red spectroscopy (FTIR) and scanning electron microscopy (SEM). The sample with maximum conductivity has been chosen to be used as an electrolyte in the magnesium solid state battery. The fabricated coin cell showed open circuit voltage (OCV) of 0.743 Volts.

  10. Materials characterization study of conductive flexible second surface mirrors

    NASA Technical Reports Server (NTRS)

    Levadou, F.; Bosma, S. J.; Paillous, A.

    1981-01-01

    The status of prequalification and qualification work on conductive flexible second surface mirrors is described. The basic material is FEP Teflon witn either aluminium or silver vacuum deposited reflectors. The top layer has been made conductive by deposition of layer of a indium oxide. The results of a prequalification program comprised of decontamination, humidity, thermal cycling, thermal shock and vibration tests are presented. Thermo-optical and electrical properties. The results of a prequalification program comprised of decontamination, humidity, thermal cycling, thermal shock and vibration tests are presented. Thermo-optical and electrical properties, the electrostatic behavior of the materials under simulated substorm environment and electrical conductivity at low temperatures are characterized. The effects of simulated ultra violet and particles irradiation on electrical and thermo-optical properties of the materials are also presented.

  11. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Foreign clinical studies not conducted under an....120 Foreign clinical studies not conducted under an IND. (a) Acceptance of studies. (1) FDA will... and well-conducted foreign clinical study not conducted under an IND, if the following conditions...

  12. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Foreign clinical studies not conducted under an....120 Foreign clinical studies not conducted under an IND. (a) Acceptance of studies. (1) FDA will... and well-conducted foreign clinical study not conducted under an IND, if the following conditions...

  13. Measuring Small-Group Environments: A Validity Study of Scores from the Salter Environmental Type Assessment and the Group Environment Scale

    ERIC Educational Resources Information Center

    Salter, Daniel W.; Junco, Reynol

    2007-01-01

    This concurrent validity study of Salter Environmental Type Assessment scores was conducted with the Group Environment Scale. A principal components factor analysis with varimax rotation of 191 college students' responses suggested two factors that accounted for 51% of the variance. The factor-analytic results and concurrent validity coefficients…

  14. Procedures for Conducting an Apprenticeship Work-Study Program.

    ERIC Educational Resources Information Center

    Millstein, Eugene J.; And Others

    This manual describes procedures for conducting a program to train personnel for educational research and development (R & D). It is intended as a guide for any institution planning to administer such a training program. The program may be utilized in several ways. They are: (1) for training various types of personnel for educational R & D; (2) as…

  15. Mössbauer study of conductive oxide glass

    NASA Astrophysics Data System (ADS)

    Matsuda, Koken; Kubuki, Shiro; Nishida, Tetsuaki

    2014-10-01

    Heat treatment of barium iron vanadate glass, BaO - Fe2O3- V2O5, at temperatures higher than crystallization temperature causes a marked decrease in resistivity (ρ) from several MΩcm to several Ωcm. 57Fe Mössbauer spectrum of heat-treated vanadate glass shows a marked decrease in quadrupole splitting (Δ) of FeIII, reflecting a structural relaxation, i.e., an increased symmetry of "distorted" FeO4 and VO4 tetrahedra which are connected to each other by sharing corner oxygen atoms. Structural relaxation of 3D-network of vanadate glass accompanies a decrease in the activation energy for the conduction, reflecting a decreased energy gap between the donor level and conduction band. A marked increase in the conductivity was observed in CuO- or Cu2O -containing barium iron vanadate glass after heat treatment at 450 °C for 30 min or more. "n-type semiconductor model combined with small polaron hopping theory" was proposed in order to explain the high conductivity.

  16. Mössbauer study of conductive oxide glass

    SciTech Connect

    Matsuda, Koken; Kubuki, Shiro; Nishida, Tetsuaki

    2014-10-27

    Heat treatment of barium iron vanadate glass, BaO‐Fe{sub 2}O{sub 3}‐V{sub 2}O{sub 5}, at temperatures higher than crystallization temperature causes a marked decrease in resistivity (ρ) from several MΩcm to several Ωcm. {sup 57}Fe Mössbauer spectrum of heat-treated vanadate glass shows a marked decrease in quadrupole splitting (Δ) of Fe{sup III}, reflecting a structural relaxation, i.e., an increased symmetry of 'distorted' FeO{sub 4} and VO{sub 4} tetrahedra which are connected to each other by sharing corner oxygen atoms. Structural relaxation of 3D-network of vanadate glass accompanies a decrease in the activation energy for the conduction, reflecting a decreased energy gap between the donor level and conduction band. A marked increase in the conductivity was observed in CuO- or Cu{sub 2}O-containing barium iron vanadate glass after heat treatment at 450 °C for 30 min or more. 'n-type semiconductor model combined with small polaron hopping theory' was proposed in order to explain the high conductivity.

  17. Study on Thermal Conductivities of Aromatic Polyimide Aerogels.

    PubMed

    Feng, Junzong; Wang, Xin; Jiang, Yonggang; Du, Dongxuan; Feng, Jian

    2016-05-25

    Polyimide aerogels for low density thermal insulation materials were produced by 4,4'-diaminodiphenyl ether and 3,3',4,4'-biphenyltetracarboxylic dianhydride, cross-linked with 1,3,5-triaminophenoxybenzene. The densities of obtained polyimide aerogels are between 0.081 and 0.141 g cm(-3), and the specific surface areas are between 288 and 322 m(2) g(-1). The thermal conductivities were measured by a Hot Disk thermal constant analyzer. The value of the measured thermal conductivity under carbon dioxide atmosphere is lower than that under nitrogen atmosphere. Under pressure of 5 Pa at -130 °C, the thermal conductivity is the lowest, which is 8.42 mW (m K)(-1). The polyimide aerogels have lower conductivity [30.80 mW (m K)(-1)], compared to the value for other organic foams (polyurethane foam, phenolic foam, and polystyrene foam) with similar apparent densities under ambient pressure at 25 °C. The results indicate that polyimide aerogel is an ideal insulation material for aerospace and other applications. PMID:27149155

  18. Motor nerve conduction study in patients on diphenylhydantoin therapy.

    PubMed Central

    Chokroverty, S; Sayeed, Z A

    1975-01-01

    Mean motor conduction velocity of posterior tibial nerves was significantly reduced in epileptic patients treated with diphenylhydantoin formore than 10 years or in patients with serum diphenylhydantoin level above 20 mug/ml. Subnormal serum folate was not responsible for this reduction and clinical peripheral neuropathy was infrequent. PMID:176326

  19. Algorithms for verbal autopsies: a validation study in Kenyan children.

    PubMed Central

    Quigley, M. A.; Armstrong Schellenberg, J. R.; Snow, R. W.

    1996-01-01

    The verbal autopsy (VA) questionnaire is a widely used method for collecting information on cause-specific mortality where the medical certification of deaths in childhood is incomplete. This paper discusses review by physicians and expert algorithms as approaches to ascribing cause of deaths from the VA questionnaire and proposes an alternative, data-derived approach. In this validation study, the relatives of 295 children who had died in hospital were interviewed using a VA questionnaire. The children were assigned causes of death using data-derived algorithms obtained under logistic regression and using expert algorithms. For most causes of death, the data-derived algorithms and expert algorithms yielded similar levels of diagnostic accuracy. However, a data-derived algorithm for malaria gave a sensitivity of 71% (95% Cl: 58-84%), which was significantly higher than the sensitivity of 47% obtained under an expert algorithm. The need for exploring this and other ways in which the VA technique can be improved are discussed. The implications of less-than-perfect sensitivity and specificity are explored using numerical examples. Misclassification bias should be taken into consideration when planning and evaluating epidemiological studies. PMID:8706229

  20. Moral judgment reloaded: a moral dilemma validation study

    PubMed Central

    Christensen, Julia F.; Flexas, Albert; Calabrese, Margareta; Gut, Nadine K.; Gomila, Antoni

    2014-01-01

    We propose a revised set of moral dilemmas for studies on moral judgment. We selected a total of 46 moral dilemmas available in the literature and fine-tuned them in terms of four conceptual factors (Personal Force, Benefit Recipient, Evitability, and Intention) and methodological aspects of the dilemma formulation (word count, expression style, question formats) that have been shown to influence moral judgment. Second, we obtained normative codings of arousal and valence for each dilemma showing that emotional arousal in response to moral dilemmas depends crucially on the factors Personal Force, Benefit Recipient, and Intentionality. Third, we validated the dilemma set confirming that people's moral judgment is sensitive to all four conceptual factors, and to their interactions. Results are discussed in the context of this field of research, outlining also the relevance of our RT effects for the Dual Process account of moral judgment. Finally, we suggest tentative theoretical avenues for future testing, particularly stressing the importance of the factor Intentionality in moral judgment. Additionally, due to the importance of cross-cultural studies in the quest for universals in human moral cognition, we provide the new set dilemmas in six languages (English, French, German, Spanish, Catalan, and Danish). The norming values provided here refer to the Spanish dilemma set. PMID:25071621

  1. Comparative study of ion conducting pathways in borate glasses

    SciTech Connect

    Hall, Andreas; Swenson, Jan; Adams, Stefan

    2006-11-01

    The conduction pathways in metal-halide doped silver, lithium, and sodium diborate glasses have been examined by bond valence analysis of reverse Monte Carlo (RMC) produced structural models of the glasses. Although all glass compositions have basically the same short-range structure of the boron-oxygen network, it is evident that the intermediate-range structure is strongly dependent on the type of mobile ion. The topography of the pathways and the coordination of the pathway sites differ distinctly between the three glass systems. The mobile silver ions in the AgI-doped glass tend to be mainly iodine-coordinated and travel in homogeneously distributed pathways located in salt-rich channels of the borate network. In the NaCl-doped glass, there is an inhomogeneous spatial distribution of pathways that reflects the inhomogeneous introduction of salt ions into the glass. However, since the salt clusters are not connected, no long-range conduction pathways are formed without including also oxygen-rich regions. The pathways in the LiCl-doped glass are slightly more evenly distributed compared to the NaCl-doped glass (but not as ordered as in the AgI-doped glass), and the regions of mainly oxygen-coordinated pathway sites are of higher importance for the long-range migration. In order to more accurately investigate how these differences in the intermediate-range order of the glasses affect the ionic conductivity, we have compared the realistic structure models to more or less randomized structures. An important conclusion from this comparison is that we find no evidence that a pronounced intermediate-range order in the atomic structure or in the network of conduction pathways, as in the AgI-doped glass, is beneficial for the dc conductivity.

  2. Comparing the Validity of Clinician-Generated Diagnosis of Conduct Disorder to the Diagnostic Interview Schedule for Children

    ERIC Educational Resources Information Center

    Jewell, Jeremy; Handwerk, Michael; Almquist, Julie; Lucas, Christopher

    2004-01-01

    Clinician diagnoses of conduct disorder (CD) were compared to the diagnoses of CD generated by a structured interview against an observed criterion. Participants were 534 youth from a large residential program in the Midwest for delinquent youth. Rates of in-program CD behaviors were gathered from staff observations of the youth over a 9-month…

  3. An international validation study of two achievement goal measures in a pharmacy education context

    PubMed Central

    Alrakaf, Saleh; Abdelmageed, Ahmed; Kiersma, Mary; Coulman, Sion A; John, Dai N; Tordoff, June; Anderson, Claire; Noreddin, Ayman; Sainsbury, Erica; Rose, Grenville; Smith, Lorraine

    2014-01-01

    Background Achievement goal theory helps us understand what motivates students to participate in educational activities. However, measuring achievement goals in a precise manner is problematic. Elliot and McGregor’s Achievement Goal Questionnaire (AGQ) and Elliot and Murayama’s revised Achievement Goal Questionnaire (AGQ-R) are widely used to assess students’ achievement goals. Both instruments were developed and validated using undergraduate psychology students in the USA. Methods In this study, our aims were to first of all, assess the construct validity of both questionnaires using a cohort of Australian pharmacy students and, subsequently, to test the generalizability and replicability of these tools more widely in schools of pharmacy in other English-speaking countries. The AGQ and the AGQ-R were administered during tutorial class time. Confirmatory factor analysis procedures, using AMOS 19 software, were performed to determine model fit. Results In contrast to the scale developers’ findings, confirmatory factor analysis supported a superior model fit for the AGQ compared with the AGQ-R, in all countries under study. Conclusion Validating measures of achievement goal motivation for use in pharmacy education is necessary and has implications for future research. Based on these results, the AGQ will be used to conduct future cross-sectional and longitudinal analyses of the achievement goals of undergraduate pharmacy students from these countries. PMID:25298743

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

    ERIC Educational Resources Information Center

    Cetin, Bayram; Yaman, Erkan; Peker, Adem

    2011-01-01

    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…

  5. A Validity Study of the Kinetic School Drawing Technique.

    ERIC Educational Resources Information Center

    Prout, H. Thompson; Celmer, David S.

    1984-01-01

    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)

  6. Conducting systematic reviews of intervention questions III: Synthesizing data from intervention studies using meta-analysis.

    PubMed

    O'Connor, A M; Sargeant, J M; Wang, C

    2014-06-01

    This article is the sixth in a series of six articles describing systematic reviews of interventions in animal agriculture and veterinary medicine. The first article provided an overview of systematic reviews, followed by an article on building evidence across study designs, and an article describing criteria for validity in randomized controlled trials. The fourth article in this series overviewed the initial steps in conducting a systematic review: development of a review protocol, identification of the structured question to be addressed and conducting a comprehensive literature search to identify potentially relevant research to address the review question. The fifth article introduced relevance screening of literature to identify and include research that is relevant to the review question, the use of standardized checklists and procedures to assess the risk of bias in the relevant research, data extraction from primary research studies and summarizing the results of the body of research identified. Many systematic reviews of interventions aim to use a quantitative method to combine the results of multiple studies and provide a more precise estimate of the effect of the intervention on the outcome, that is, a summary effect measure. The objective of this article was to describe general approaches that are available for quantitative synthesis of data. Specific details of all meta-analysis statistical approaches are beyond the capacity of this article. PMID:24905996

  7. Sound Transmission Validation and Sensitivity Studies in Numerical Models.

    PubMed

    Oberrecht, Steve P; Krysl, Petr; Cranford, Ted W

    2016-01-01

    In 1974, Norris and Harvey published an experimental study of sound transmission into the head of the bottlenose dolphin. We used this rare source of data to validate our Vibroacoustic Toolkit, an array of numerical modeling simulation tools. Norris and Harvey provided measurements of received sound pressure in various locations within the dolphin's head from a sound source that was moved around the outside of the head. Our toolkit was used to predict the curves of pressure with the best-guess input data (material properties, transducer and hydrophone locations, and geometry of the animal's head). In addition, we performed a series of sensitivity analyses (SAs). SA is concerned with understanding how input changes to the model influence the outputs. SA can enhance understanding of a complex model by finding and analyzing unexpected model behavior, discriminating which inputs have a dominant effect on particular outputs, exploring how inputs combine to affect outputs, and gaining insight as to what additional information improves the model's ability to predict. Even when a computational model does not adequately reproduce the behavior of a physical system, its sensitivities may be useful for developing inferences about key features of the physical system. Our findings may become a valuable source of information for modeling the interactions between sound and anatomy. PMID:26611033

  8. Validation study of the Questionnaire on School Maladjustment Problems (QSMP).

    PubMed

    de la Fuente Arias, Jesús; Peralta Sánchez, Francisco Javier; Sánchez Roda, María Dolores; Trianes Torres, María Victoria

    2012-05-01

    The aim of this study was to analyze the exploratory and confirmatory structure, as well as other psychometric properties, of the Cuestionario de Problemas de Convivencia Escolar (CPCE; in Spanish, the Questionnaire on School Maladjustment Problems [QSMP]), using a sample of Spanish adolescents. The instrument was administered to 60 secondary education teachers (53.4% females and 46.6% males) between the ages of 28 and 54 years (M= 41.2, SD= 11.5), who evaluated a total of 857 adolescent students. The first-order exploratory factor analysis identified 7 factors, explaining a total variance of 62%. A second-order factor analysis yielded three dimensions that explain 84% of the variance. A confirmatory factor analysis was subsequently performed in order to reduce the number of factors obtained in the exploratory analysis as well as the number of items. Lastly, we present the results of reliability, internal consistency, and validity indices. These results and their implications for future research and for the practice of educational guidance and intervention are discussed in the conclusions. PMID:22420365

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

    SciTech Connect

    Benjamin Michael Meyer

    2003-05-31

    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?

  10. The College Board SAT® Writing Validation Study: An Assessment of Predictive and Incremental Validity. Research Report No. 2006-2

    ERIC Educational Resources Information Center

    Norris, Dwayne; Oppler, Scott; Kuang, Daniel; Day, Rachel; Adams, Kimberly

    2006-01-01

    This study assessed the predictive and incremental validity of a prototype version of the forthcoming SAT® writing section that was administered to a sample of incoming students at 13 colleges and universities. For these participants, SAT scores, high school GPA, and first-year grades also were obtained. Using these data, analyses were conducted…

  11. AOAC Official MethodSM Matrix Extension Validation Study of Assurance GDSTM for the Detection of Salmonella in Selected Spices.

    PubMed

    Feldsine, Philip; Kaur, Mandeep; Shah, Khyati; Immerman, Amy; Jucker, Markus; Lienau, Andrew

    2015-01-01

    Assurance GDSTM for Salmonella Tq has been validated according to the AOAC INTERNATIONAL Methods Committee Guidelines for Validation of Microbiological Methods for Food and Environmental Surfaces for the detection of selected foods and environmental surfaces (Official Method of AnalysisSM 2009.03, Performance Tested MethodSM No. 050602). The method also completed AFNOR validation (following the ISO 16140 standard) compared to the reference method EN ISO 6579. For AFNOR, GDS was given a scope covering all human food, animal feed stuff, and environmental surfaces (Certificate No. TRA02/12-01/09). Results showed that Assurance GDS for Salmonella (GDS) has high sensitivity and is equivalent to the reference culture methods for the detection of motile and non-motile Salmonella. As part of the aforementioned validations, inclusivity and exclusivity studies, stability, and ruggedness studies were also conducted. Assurance GDS has 100% inclusivity and exclusivity among the 100 Salmonella serovars and 35 non-Salmonella organisms analyzed. To add to the scope of the Assurance GDS for Salmonella method, a matrix extension study was conducted, following the AOAC guidelines, to validate the application of the method for selected spices, specifically curry powder, cumin powder, and chili powder, for the detection of Salmonella. PMID:26268975

  12. Experimental study of wide bandgap transparent conducting oxide thin films

    NASA Astrophysics Data System (ADS)

    Yan, Min

    Epitaxial growth of both pure and doped CdO thin films has been achieved on MgO (111) substrates using pulsed laser deposition (PLD). A maximum conductivity of 42,000 S/cm with mobility of 609 cm2/V· s was achieved when the CdO epitaxial film was doped with 2.5% Sn. The pure CdO epitaxial film had a bandgap of 2.4 eV. The bandgap increased with doping and reaches a maximum of 2.87 eV when the doping level was 6.2%. Both grain boundary scattering and ionized impurity scattering were found to contribute to the mobility of CdO films. Multilayered TCO thin film structures have been designed to achieve both high conductivity and high transmittance in the visible range. The double-layered TCO structures consisted of Sri doped CdO film as conductive layer, and either Sri doped CdIn2O4 or Cd rich Cd2SnO 4 or Ga doped ZnO film as transparent layer. By optimizing the layer thickness and/or doping levels, effective conductivity of 20,600 S/cm and an average transmittance larger than 85% in the range of 400--700 nm have been achieved. These properties are attractive for future TCO applications. Templated ZnO thin film growth from the vapor phase was achieved on docosyltrichlorosilane-patterned Si substrates using atomic layer epitaxy (ALE) combined with soft lithography. Patterned hydrophobic self-assembled monolayers (SAMs) were first transferred to single-crystal Si surfaces by hot microcontact printing. Using diethylzinc and water as ALE precursors, crystalline ZnO layers were then grown selectively on the SAM-free surface regions where native hydroxyl groups nucleated growth from the vapor phase. High-resolution ZnO patterns with 1.0 mum--40 mum feature sizes were readily achieved, demonstrating that soft lithography combined with ALE is a simple and promising methodology for selective area in situ vapor phase fabrication of patterned oxide thin films. Highly oriented Ga doped ZnO nano-rod arrays were fabricated by PLD on GaN and sapphire substrates. X-ray diffraction revealed that these nano-rods are epitaxial c-plane ZnO. The growth of the ZnO nano-rods was found to be electric-field-assisted. The morphology of the ZnO nano-rods is mainly determined by the Ga doping level and the substrate temperature. These ordered ZnO nano-rod arrays are attractive for field emission and optoelectronic applications.

  13. Molecular modelling approaches for cystic fibrosis transmembrane conductance regulator studies.

    PubMed

    Odolczyk, Norbert; Zielenkiewicz, Piotr

    2014-07-01

    Cystic fibrosis (CF) is one of the most common genetic disorders, caused by loss of function mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) protein. CFTR is a member of ATP-binding cassette (ABC) transporters superfamily and functions as an ATP-gated anion channel. This review summarises the vast majority of the efforts which utilised molecular modelling approaches to gain insight into the various aspects of CFTR protein, related to its structure, dynamic properties, function and interactions with other protein partners, or drug-like compounds, with emphasis to its relation to CF disease. PMID:24735712

  14. Injection Drug Use Quality of Life scale (IDUQOL): A validation study

    PubMed Central

    Hubley, Anita M; Russell, Lara B; Palepu, Anita

    2005-01-01

    Background Existing measures of injection drug users' quality of life have focused primarily on health and health-related factors. Clearly, however, quality of life among injection drug users is impacted by a range of unique cultural, socioeconomic, medical, and geographic factors that must also be considered in any measure. The Injection Drug User Quality of Life (IDUQOL) scale was designed to capture the unique and individual circumstances that determine quality of life among injection drug users. The overall purpose of the present study was to examine the validity of inferences made from the IDUQOL by examining the (a) dimensionality, (b) reliability of scores, (c) criterion-related validity evidence, and (d) both convergent and discriminant validity evidence. Methods An exploratory factor analysis using principal axis factoring in SPSS 12.0 was conducted to determine whether the use of a total score on the IDUQOL was advisable. Reliability of scores from the IDUQOL was obtained using internal consistency and one-week test-retest reliability estimates. Criterion-related validity evidence was gathered using variables such as stability of housing, sex trade involvement, high-risk injection behaviours, involvement in treatment programs, emergency treatment or overdose over the previous six months, hospitalization and emergency treatment over the subsequent six month period post data collection. Convergent and discriminant validity evidence was gathered using measures of life satisfaction, self-esteem, and social desirability. Results The sample consisted of 241 injection drug users ranging in age from 19 to 61 years. Factor analysis supports the use of a total score. Both internal consistency (alpha = .88) and one-week test-retest reliability (r = .78) for IDUQOL total scores were good. Criterion-related, convergent, and discriminant validity evidence supports the interpretation of IDUQOL total scores as measuring a construct consistent with quality of life. Conclusion The findings from this study provide initial evidence to support the use of the IDUQOL total score. The results of the study also suggest the IDUQOL could be further strengthened with additional attention to how some IDUQOL domains are described and satisfaction is measured. PMID:16029504

  15. Comparison of Automated versus Traditional Nerve Conduction Study Methods for Median Nerve Testing in a General Worker Population

    PubMed Central

    Dale, Ann Marie; Agboola, Folasade; Yun, Amber; Zeringue, Angelique; Al-Lozi, Muhammed T.; Evanoff, Bradley

    2014-01-01

    Objective To investigate the validity of automated nerve conduction studies compared to traditional electrodiagnostic studies (EDS) for testing median nerve abnormalities in a working population. Design Agreement study and sensitivity investigation from two devices Setting Field research testing lab Participants Active workers from several industries participating in a longitudinal study of CTS. Methods Sixty-two subjects received bilateral median and ulnar nerve conduction testing across the wrist with a traditional device and the NC-stat automated device. We compared intermethod agreement of analogous measurements. Main outcome measurement Nerve conduction study parameters Results Median motor and sensory latency comparisons showed excellent agreement (intra-class correlation 0.85 and 0.80 respectively). Areas under the receiver operator characteristic curves were 0.97 and 0.96 respectively, using the optimal thresholds of 4.4ms median motor latency (sensitivity 100%, specificity 86%) and 3.9ms median sensory latency (sensitivity 100%, specificity 87%). Ulnar nerve testing results were less favorable. Conclusion The automated NC-stat device showed excellent agreement with traditional EDS for detecting median nerve conduction abnormalities in a general population of workers, suggesting that this automated nerve conduction device can be used to ascertain research case definitions of CTS in population health studies. Further study is needed to determine optimal thresholds for defining median conduction abnormalities in populations that are not seeking clinical care. PMID:25463687

  16. Scanning Ion Conductance Microscopy for Studying Biological Samples

    PubMed Central

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

    2012-01-01

    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

  17. Structural and AC conductivity study of CdTe nanomaterials

    NASA Astrophysics Data System (ADS)

    Das, Sayantani; Banerjee, Sourish; Sinha, T. P.

    2016-04-01

    Cadmium telluride (CdTe) nanomaterials have been synthesized by soft chemical route using mercapto ethanol as a capping agent. Crystallization temperature of the sample is investigated using differential scanning calorimeter. X-ray diffraction and transmission electron microscope measurements show that the prepared sample belongs to cubic structure with the average particle size of 20 nm. Impedance spectroscopy is applied to investigate the dielectric relaxation of the sample in a temperature range from 313 to 593 K and in a frequency range from 42 Hz to 1.1 MHz. The complex impedance plane plot has been analyzed by an equivalent circuit consisting of two serially connected R-CPE units, each containing a resistance (R) and a constant phase element (CPE). Dielectric relaxation peaks are observed in the imaginary parts of the spectra. The frequency dependence of real and imaginary parts of dielectric permittivity is analyzed using modified Cole-Cole equation. The temperature dependence relaxation time is found to obey the Arrhenius law having activation energy ~0.704 eV. The frequency dependent conductivity spectra are found to follow the power law. The frequency dependence ac conductivity is analyzed by power law.

  18. Alaska North Slope Tundra Travel Model and Validation Study

    SciTech Connect

    Harry R. Bader; Jacynthe Guimond

    2006-03-01

    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.

  19. Experimental study of 3D contactless conductivity detection using microwave radiometry: a possible method for investigation of brain conductivity fluctuations.

    PubMed

    Karanasiou, I S; Uzunoglu, N K

    2004-01-01

    The capability of detecting electrical conductivity variations using focused microwave radiometry, a method used in clinical applications for temperature distribution imaging of subcutaneous tissues, is discussed in the present study. A novel microwave radiometric system operating at 3.5 GHz, including an ellipsoidal conductive wall cavity, which provides the required beamforming and focusing, is developed. The system is capable of providing distribution measurements of the product of conductivity and temperature of any object being at a temperature above the absolute zero. The implemented experimental procedure is based on the results of an electromagnetic numerical analysis using a semianalytical method which was developed in order to compute the focusing properties of the ellipsoidal reflector. Each measurement is realized by placing the region of interest in the area of the first focus of the cavity and collecting the radiation converged at the second by an almost isotropic dipole antenna connected to a sensitive radiometer. Experimental data from cylindrical shaped saline or de-ionized water filled tank phantoms in which saline solutions of different concentrations were infused, provide promising results concerning the system's ability of detecting conductivity variations. Future research is needed in order to elucidate the potential of the proposed methodology to be used for brain conductivity measurements. PMID:17272189

  20. Turkish validity and reliability study of the Weiss Functional Impairment Rating Scale-Parent Report.

    PubMed

    Tarakçıoğlu, Mahmut C; Memik, Nursu Çakın; Olgun, Nesligül N; Aydemir, Ömer; Weiss, Margaret D

    2015-06-01

    Attention deficit hyperactivity disorder (ADHD) is seen frequently in childhood and leads to marked impairment in functioning. There is no scale in Turkey with documented validity and reliability that assesses ADHD-specific functional impairment (FI). This study aimed at adapting the Weiss Functional Impairment Rating Scale-Parent Report (WFIRS-P), which assesses ADHD-related FI, for use in Turkey, and examining psychometric aspects of the scale. The study included 250 children diagnosed with ADHD and 250 healthy children and their parents. Internal consistency and test-retest methods were used to test the reliability of the scale. Validity was tested with exploratory and confirmatory factor analyses and convergent and discriminant validity analyses. Since all six questions of the WFIRS-P were scored 0, analyses were conducted for the original scale questionnaire consisting of 50 items and the questionnaire consisting of 44 items where the six questions scored 0 were not included. The Cronbach's alpha coefficient was 0.93 for the whole scale. The Spearman's correlation coefficient was 0.93 for test-retest reliability. The exploratory factor analysis run on the 44-item questionnaire showed that the scale items were best represented in a 7-factor structure, but some items were placed in different subdomains than those of the original scale. In the confirmatory factor analysis, the root mean square error of approximation was 0.061, and the comparative fit index was 0.95 for the whole model. Therefore, the Turkish WFIRS-P is valid and reliable in testing functional impairment in children with ADHD. PMID:25428590

  1. Validating a satisfaction questionnaire using multiple approaches: a case study.

    PubMed

    Etter, J F; Perneger, T V

    1997-09-01

    We examined the validity of a questionnaire designed to measure the satisfaction of users of health services, using multiple tests of construct validity. Members of 2 health insurance plans in Geneva (Switzerland) answered a mailed questionnaire in 1992 (n = 1007) and 1993 (n = 1424). Response rates were 82% participants were 18-44 years old in 1992. The questionnaire included 22 questions on satisfaction with medical care received during the past 12 months. Most items were adapted from the Patient Satisfaction Questionnaire. Four dimensions of satisfaction were measured: satisfaction with physician services (8 items), communication (8 items), access (4 items) and insurance services (2 items). Reliability (Cronbach's alpha) was satisfactory for the 2 former dimensions (alpha = 0.81 and 0.82 respectively), but lower than desired for the 2 latter (alpha = 0.63 and 0.49 respectively). Participants who gave positive open-ended comments had satisfaction scores 0.7-1.2 standard deviation units higher than participants who gave negative comments. Satisfaction scores were weakly correlated with satisfaction with private life, which indicates that the instrument did not simply measure a general tendency to be satisfied. Participants who said that care received in 1993 was worse than care received in 1992 (retrospective assessment) experienced a decrease in satisfaction scores between 1992 and 1993 (prospective assessment). Most validation procedures provided independent but partial evidence for the validity of the instrument. Triangulation of several validation methods, as illustrated in this paper, may greatly improve the understanding of an instrument's properties. PMID:9255920

  2. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... (c) Initial study report. (1) Pursuant to the Commission-approved study plan and schedule provided... first, the potential applicant must prepare and file with the Commission an initial study report... an explanation of any variance from the study plan and schedule. The report must also include...

  3. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    .... (c) Initial study report. (1) Pursuant to the Commission-approved study plan and schedule provided... first, the potential applicant must prepare and file with the Commission an initial study report... an explanation of any variance from the study plan and schedule. The report must also include...

  4. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... (c) Initial study report. (1) Pursuant to the Commission-approved study plan and schedule provided... first, the potential applicant must prepare and file with the Commission an initial study report... an explanation of any variance from the study plan and schedule. The report must also include...

  5. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... (c) Initial study report. (1) Pursuant to the Commission-approved study plan and schedule provided... first, the potential applicant must prepare and file with the Commission an initial study report... an explanation of any variance from the study plan and schedule. The report must also include...

  6. Physics validation studies for muon collider detector background simulations

    SciTech Connect

    Morris, Aaron Owen; /Northern Illinois U.

    2011-07-01

    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.

  7. A Validation Study of the Thinking Styles Inventory: Implications for Gifted Education.

    ERIC Educational Resources Information Center

    Dai, David Yun; Feldhusen, John F.

    1999-01-01

    A study involving 96 gifted adolescents examined internal and external validity of the Thinking Styles Inventory (TSI) within the framework of Sternberg's (1988) theory of mental self-government. Results provided evidence of the external discriminant validity but lent only partial support to the internal validity of the instrument. (Author/CR)

  8. Study on the Validity and Reliability of Melbourne Decision Making Scale in Turkey

    ERIC Educational Resources Information Center

    Çolakkadioglu, Oguzhan; Deniz, M. Engin

    2015-01-01

    This study is to analyze the validity and reliability of Melbourne Decision Making Questionnaire (MDMQ). The sample consisted of 650 university students. The structural validity of the MDMQ, as well as correlations among its sub-scales, measure-bound validity, internal consistency, item total correlations and test-retest reliability coefficients…

  9. Study on the Validity and Reliability of Melbourne Decision Making Scale in Turkey

    ERIC Educational Resources Information Center

    olakkadioglu, Oguzhan; Deniz, M. Engin

    2015-01-01

    This study is to analyze the validity and reliability of Melbourne Decision Making Questionnaire (MDMQ). The sample consisted of 650 university students. The structural validity of the MDMQ, as well as correlations among its sub-scales, measure-bound validity, internal consistency, item total correlations and test-retest reliability coefficients

  10. Propeller aircraft interior noise model utilization study and validation

    NASA Technical Reports Server (NTRS)

    Pope, L. D.

    1984-01-01

    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.

  11. A Predictive Validity Study of the Pharmacy College Admission Test

    PubMed Central

    Meagher, Donald G.; Lin, Anli; Stellato, Christina P.

    2006-01-01

    Objective To examine the validity of Pharmacy College Admission Test (PCAT) scores for predicting grade point averages (GPAs) of students in years 1-4 of pharmacy programs. Methods Data were collected from 11 colleges and schools of pharmacy: entering cumulative and math/science GPAs, PCAT scaled scores, pharmacy program GPAs for years 1-4, student status after 4 years. Correlation, regression, discriminant, and diagnostic accuracy analyses were used to determine the validity of the PCAT for predicting subsequent GPAs. Results PCAT scaled scores and entering GPAs were positively correlated with subsequent GPAs. Regression analyses showed the predictive value of the PCAT scores, especially in combination with entering GPAs. Discriminant and diagnostic accuracy analyses supported these findings and provided practical suggestions regarding optimal PCAT scores for identifying students most likely to succeed. Conclusion Both PCAT scaled scores and entering cumulative GPAs showed moderate to strong predictive validity as indicators of candidates likely to succeed in pharmacy school. PMID:17136174

  12. Scanning ion conductance microscopy studies of amyloid fibrils at nanoscale

    NASA Astrophysics Data System (ADS)

    Zhang, Shuai; Cho, Sang-Joon; Busuttil, Katerina; Wang, Chen; Besenbacher, Flemming; Dong, Mingdong

    2012-05-01

    Atomic force microscopy (AFM) has developed to become a very versatile nano-scale technique to reveal the three-dimensional (3D) morphology of amyloid aggregates under physiological conditions. However, the imaging principle of AFM is based on measuring the `force' between a sharp tip and a given nanostructure, which may cause mechanical deformation of relatively soft objects. To avoid the deformation, scanning ion conductance microscopy (SICM) is an alternative scanning probe microscopy technique, operating with alternating current mode. Here we can indeed reveal the 3D morphology of amyloid fibrils and it is capable of exploring proteins with nanoscale resolution. Compared with conventional AFM, we show that SICM can provide precise height measurements of amyloid protein aggregates, a feature that enables us to obtain unique insight into the detailed nucleation and growth mechanisms behind amyloid self-assembly.

  13. Disentangling the Underlying Dimensions of Psychopathy and Conduct Problems in Childhood: A Community Study

    ERIC Educational Resources Information Center

    Dadds, Mark R.; Fraser, Jenny; Frost, Aaron; Hawes, David J.

    2005-01-01

    The psychometric and predictive validity of callous-unemotional (CU) traits as an early precursor of conduct disorder and antisocial behavior were assessed. A community sample of children (4-9 years of age) were tested 12 months apart with the Antisocial Process Screening Device (APSD; P. J. Frick & R. D. Hare, 2002), a measure of early signs of…

  14. Simulation verification techniques study. Subsystem simulation validation techniques

    NASA Technical Reports Server (NTRS)

    Duncan, L. M.; Reddell, J. P.; Schoonmaker, P. B.

    1974-01-01

    Techniques for validation of software modules which simulate spacecraft onboard systems are discussed. An overview of the simulation software hierarchy for a shuttle mission simulator is provided. A set of guidelines for the identification of subsystem/module performance parameters and critical performance parameters are presented. Various sources of reference data to serve as standards of performance for simulation validation are identified. Environment, crew station, vehicle configuration, and vehicle dynamics simulation software are briefly discussed from the point of view of their interfaces with subsystem simulation modules. A detailed presentation of results in the area of vehicle subsystems simulation modules is included. A list of references, conclusions and recommendations are also given.

  15. Validation Study of the Mini-Mental State Examination in Urdu Language for Pakistani Population

    PubMed Central

    Awan, Safia; Shahbaz, Naila; Akhtar, Syed Wasim; Ahmad, Arsalan; Iqbal, Sadaf; Ahmed, Sellal; Naqvi, Haider; Wasay, Mohammad

    2015-01-01

    Validation study of the Mini-Mental State Examination in Urdu language for Pakistani population Objective: This study was conducted primarily to validate and determine the optimal cutoff score in the diagnosis of dementia among Pakistani’s and study the effects of gender and education on the MMSE performance in our population. Methods: Four hundred participants took part in the study. Patient with dementia recruited from five major hospitals from Pakistan. The MMSE was translated into Urdu. Results: There were 61 men and 39 women in dementia group and 225 men and 75 women in the control group. The mean score of Urdu MMSE were lower in patients with dementia 18.5 ± 5.6 (range 0-30) as compared to the controls 26.8 ± 2.6 (range 7-30). This difference between groups was statistically significant (p<0.001). Educational based MMSE score below 15 yielded perfect sensitivity and specificity for the diagnosis of dementia. Conclusions: These finding confirm the influence of level of education on MMSE score and education stratified cutoff scores should be used while screening for cognitive impairment in this population. PMID:26191094

  16. Independent validation test of the vote-counting strategy used to rank biomarkers from published studies

    PubMed Central

    Rikke, Brad A.; Wynes, Murry W.; Rozeboom, Leslie M.; Barn, Anna E.; Hirsch, Fred R.

    2016-01-01

    Aim Vote counting is frequently used in meta-analyses to rank biomarker candidates, but to our knowledge, there have been no independent assessments of its validity. Here, we used predictions from a recent meta-analysis to determine how well number of supporting studies, combined sample size and mean fold change performed as vote-counting strategy criteria. Materials & methods Fifty miRNAs previously ranked for their ability to distinguish lung cancer tissue from normal were assayed by RT-qPCR using 45 paired tumor-normal samples. Results Number of supporting studies predicted biomarker performance (p = 0.0006; r = 0.44), but sample size and fold change did not (p > 0.2). Conclusion Despite limitations, counting the number supporting studies appears to be an effective criterion for ranking biomarkers. Predictions based on sample size and fold change provided little added value. External validation studies should be conducted to establish the performance characteristics of strategies used to rank biomarkers. PMID:26223535

  17. Virtual Faces Expressing Emotions: An Initial Concomitant and Construct Validity Study

    PubMed Central

    Joyal, Christian C.; Jacob, Laurence; Cigna, Marie-Hélène; Guay, Jean-Pierre; Renaud, Patrice

    2014-01-01

    Background: Facial expressions of emotions represent classic stimuli for the study of social cognition. Developing virtual dynamic facial expressions of emotions, however, would open-up possibilities, both for fundamental and clinical research. For instance, virtual faces allow real-time Human–Computer retroactions between physiological measures and the virtual agent. Objectives: The goal of this study was to initially assess concomitants and construct validity of a newly developed set of virtual faces expressing six fundamental emotions (happiness, surprise, anger, sadness, fear, and disgust). Recognition rates, facial electromyography (zygomatic major and corrugator supercilii muscles), and regional gaze fixation latencies (eyes and mouth regions) were compared in 41 adult volunteers (20 ♂, 21 ♀) during the presentation of video clips depicting real vs. virtual adults expressing emotions. Results: Emotions expressed by each set of stimuli were similarly recognized, both by men and women. Accordingly, both sets of stimuli elicited similar activation of facial muscles and similar ocular fixation times in eye regions from man and woman participants. Conclusion: Further validation studies can be performed with these virtual faces among clinical populations known to present social cognition difficulties. Brain–Computer Interface studies with feedback–feedforward interactions based on facial emotion expressions can also be conducted with these stimuli. PMID:25324768

  18. [Burned-out or depressive? An empirical study regarding the construct validity of burnout in contrast to depression].

    PubMed

    Reime, B; Steiner, I

    2001-08-01

    Our study tested the discriminant validity of burnout in contrast to depression using the Maslach Burnout Inventory (MBI, Maslach u. Jackson 1986) and the Allgemeine Depressionsskala (ADS, Hautzinger u. Bailer 1993). Furthermore the relationships between burnout and depression to social support, occupational and health variables were examined. Pre-school teachers (n = 101), physician-assistants (n = 81) and their intimates were asked to complete a self-administered questionnaire. Spearman-correlations and factor analysis were conducted with SPSS. The results indicate validity for the burnout construct. PMID:11536072

  19. The Social Interest Index: A Study of Construct Validity.

    ERIC Educational Resources Information Center

    Mozdzierz, Gerald J.; Semyck, Roger W.

    1980-01-01

    Investigated construct validity of the Social Interest Index (SII) with 140 male alcoholics. Hypothesized that the SII would relate positively with measures of mental health, intelligence, education, and internal locus of control and would relate negatively with measures of MMPI "pathology" scales. The hypotheses generally were supported. (Author)

  20. A Validity Study of the Salter Environmental Type Assessment.

    ERIC Educational Resources Information Center

    Salter, Daniel W.

    2002-01-01

    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…

  1. Behavioral and Emotional Rating Scale: Two Studies of Convergent Validity

    ERIC Educational Resources Information Center

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

    2003-01-01

    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 strengths…

  2. Ecological Validity in Eye-Tracking: An Empirical Study

    ERIC Educational Resources Information Center

    Spinner, Patti; Gass, Susan M.; Behney, Jennifer

    2013-01-01

    Eye-trackers are becoming increasingly widespread as a tool to investigate second language (L2) acquisition. Unfortunately, clear standards for methodology--including font size, font type, and placement of interest areas--are not yet available. Although many researchers stress the need for ecological validity--that is, the simulation of natural…

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

    ERIC Educational Resources Information Center

    Wickramasinghe, Vathsala M.

    2006-01-01

    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 different

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

    ERIC Educational Resources Information Center

    Wickramasinghe, Vathsala M.

    2006-01-01

    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 different…

  5. The Caregiver Role Identity Scale: A Validation Study

    ERIC Educational Resources Information Center

    Siebert, Darcy Clay; Siebert, Carl F.

    2005-01-01

    Objective: This article reports the validation of the Caregiver Role Identity Scale, designed to measure the prominence of helping professionals' identity as personal and professional caregivers. The authors developed the measure to test its application to burnout, depression, and professional impairment among social workers. Method: Data from a…

  6. Measuring Elementary Student's Mathematics Motivation: A Validity Study

    ERIC Educational Resources Information Center

    Orosco, Michael J.

    2016-01-01

    The psychometric properties of a 10-item math motivation scale were empirically validated with an independent sample consisting of 182 elementary-school students. Analysis of the model dimensionality supported a one-factor structure fit. Item parameter estimates from a Classical Test Theory framework revealed that most items were highly…

  7. Rediscovery rate estimation for assessing the validation of significant findings in high-throughput studies.

    PubMed

    Ganna, Andrea; Lee, Donghwan; Ingelsson, Erik; Pawitan, Yudi

    2015-07-01

    It is common and advised practice in biomedical research to validate experimental or observational findings in a population different from the one where the findings were initially assessed. This practice increases the generalizability of the results and decreases the likelihood of reporting false-positive findings. Validation becomes critical when dealing with high-throughput experiments, where the large number of tests increases the chance to observe false-positive results. In this article, we review common approaches to determine statistical thresholds for validation and describe the factors influencing the proportion of significant findings from a 'training' sample that are replicated in a 'validation' sample. We refer to this proportion as rediscovery rate (RDR). In high-throughput studies, the RDR is a function of false-positive rate and power in both the training and validation samples. We illustrate the application of the RDR using simulated data and real data examples from metabolomics experiments. We further describe an online tool to calculate the RDR using t-statistics. We foresee two main applications. First, if the validation study has not yet been collected, the RDR can be used to decide the optimal combination between the proportion of findings taken to validation and the size of the validation study. Secondly, if a validation study has already been done, the RDR estimated using the training data can be compared with the observed RDR from the validation data; hence, the success of the validation study can be assessed. PMID:25256289

  8. Conducting influenza virus pathogenesis studies in avian species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian infection studies with influenza A are an important means of assessing host susceptibility, viral pathogenesis, host responses to infection, mechanisms of transmission and viral pathotype. Complex systems and natural settings may also be explored with carefully designed infection studies. In ...

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

    PubMed

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

    1999-08-01

    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

  10. Pesticides and cancer: the first incidence study conducted in Turkey.

    PubMed

    Uysal, Mukremin; Bozcuk, Hakan; Karakilinc, Hulya; Goksu, Sema; Tatli, Ali Murat; Gunduz, Seyda; Arslan, Deniz; Coskun, Hasan Senol; Savas, Burhan

    2013-01-01

    The incidence of cancer is increasing in Turkey and worldwide. One of the reasons for this increase may be the consumption of products that are grown in greenhouses with the intensive use of pesticides. For this reason, this study was carried out in Antalya, where the most intensive greenhouse cultivation is performed in Turkey. This study investigated the relationship between cancer types and total area of the agricultural field where the greenhouse activities were performed. Results of this study showed that there was a statistically significant relationship between the increased incidence of multiple myeloma, acute lymphocytic leukemia, and malignant melanoma with an increase in the total area of agricultural field. PMID:24266411

  11. Health problem behaviors in Iranian adolescents: a study of cross-cultural adaptation, reliability, and validity

    PubMed Central

    Eslami, Ahmad Ali; Ghofranipour, Fazlollah; Bonab, Bagher Ghobari; Zadeh, Davood Shojaei; Shokravi, Farkhondeh Amin; Tabatabaie, Mahmoud Ghazi

    2010-01-01

    BACKGROUND: The main purpose of this study was to assess the factorial validity and reliability of the Iranian versions of the personality and behavior system scales (49 items) of the AHDQ (The Adolescent Health and Development Questionnaire) and interrelations among them based on Jessor’s PBT (Problem Behavior Theory). METHODS: A multi-staged approach was employed. The cross-cultural adaptation was performed according to the internationally recommended methodology, using the following guidelines: translation, back-translation, revision by a committee, and pretest. After modifying and identifying of the best items, a cross-sectional study was conducted to assess the psychometric properties of Persian version using calibration and validation samples of adolescents. Also 113 of them completed it again two weeks later for stability. RESULTS: The findings of the exploratory factor analysis suggested that the 7-factor solution with low self concept, emotional distress, general delinquency, cigarette, hookah, alcohol, and hard drugs use provided a better fitting model. The α range for these identified factors was 0.69 to 0.94, the ICC range was 0.73 to 0.93, and there was a significant difference in mean scores for these instruments in compare between the male normative and detention adolescents. The first and second-order measurement models testing found good model fit for the 7-factor model. CONCLUSIONS: Factor analyses provided support of existence internalizing and externalizing problem behavior syndrome. With those qualifications, this model can be applied for studies among Persian adolescents. PMID:21526075

  12. The knowledge, efficacy, and practices instrument for oral health providers: a validity study with dental students.

    PubMed

    Behar-Horenstein, Linda S; Garvan, Cyndi W; Moore, Thomas E; Catalanotto, Frank A

    2013-08-01

    Valid and reliable instruments to measure and assess cultural competence for oral health care providers are scarce in the literature, and most published scales have been contested due to a lack of item analysis and internal estimates of reliability. The purposes of this study were, first, to develop a standardized instrument to measure dental students' knowledge of diversity, skills in culturally competent patient-centered communication, and use of culture-centered practices in patient care and, second, to provide preliminary validity support for this instrument. The initial instrument used in this study was a thirty-six-item Likert-scale survey entitled the Knowledge, Efficacy, and Practices Instrument for Oral Health Providers (KEPI-OHP). This instrument is an adaption of an initially thirty-three-item version of the Multicultural Awareness, Knowledge, and Skills Scale-Counselor Edition (MAKSS-CE), a scale that assesses factors related to social justice, cultural differences among clients, and cross-cultural client management. After the authors conducted cognitive and expert interviews, focus groups, pilot testing, and item analysis, their initial instrument was reduced to twenty-eight items. The KEPI-OHP was then distributed to 916 dental students (response rate=48.6 percent) across the United States to measure its reliability and assess its validity. Both exploratory and confirmatory factor analyses were conducted to test the scale's validity. The modification of the survey into a sensible instrument with a relatively clear factor structure using factor analysis resulted in twenty items. A scree test suggested three expressive factors, which were retained for rotation. Bentler's comparative fit and Bentler and Bonnett's non-normed indices were 0.95 and 0.92, respectively. A three-factor solution, including efficacy of assessment, knowledge of diversity, and culture-centered practice subscales, comprised of twenty-items was identified. The KEPI-OHP was found to have reasonable internal consistency reliability to warrant its use for baseline and repeated measures in assessing changes in dental students' growth in cultural competence across four-year dental curricula. PMID:23929569

  13. SELDI Validation Study Phase II — EDRN Public Portal

    Cancer.gov

    This project –A Comprehensive Program for the Validation of Prostate Cancer Early Detection with Novel Protein Identification Techniques -- is divided into three phases. The goal of Phase I was to assess the reproducibility and portability of Surface-Enhanced Laser Desorption and Ionization time-of-flight mass spectrometry (SELDI-TOF-MS) using protein profiles generated from serum. Phase I was recently successfully completed at six institutions using a single source of pooled sera.

  14. Being an Insider Researcher while Conducting Case Study Research

    ERIC Educational Resources Information Center

    Unluer, Sema

    2012-01-01

    It is crucial for social researchers to clarify their researchers' roles, especially for those utilizing qualitative methodology to make their research credible. The purpose of this paper is to examine the advantages and disadvantages of the researcher's insider role, an instructor, occupied within case study research on the integration of…

  15. Reanalysis of the Harvard Six Cities Study, part I: validation and replication.

    PubMed

    Krewski, D; Burnett, R T; Goldberg, M; Hoover, K; Siemiatycki, J; Abrahamowicz, M; White, W

    2005-01-01

    Because the results of the Harvard Six Cities Study played a critical role in the establishment of the current U.S. ambient air quality objective for fine particles (PM(2.5)), the U.S. Environmental Protection Agency, industry, and nongovernmental organizations called for an independent reanalysis of this study to validate the original findings reported by Dockery and colleagues in the New England Journal of Medicine (vol. 329, pp. 1753-1759) in 1993. Validation of the original findings was accomplished by a detailed statistical audit and replication of original results. With the exception of occupational exposure to dust (14 discrepancies of 249 questionnaires located for evaluation) and fumes (15/249), date of death (2/250), and cause of death (2/250), the audit identified no discrepancies between the original questionnaires and death certificates in the audit sample and the analytic file used by the original investigators. The data quality audit identified a computer programming problem that had resulted in early censorship in 5 of the 6 cities, which resulted in the loss of approximately 1% of the reported person-years of follow-up; the reanalysis team updated the Six Cities cohort to include the missing person-years of observation, resulting in the addition of 928 person-years of observation and 14 deaths. The reanalysis team was able to reproduce virtually all of the original numerical results, including the 26% increase in all-cause mortality in the most polluted city (Stubenville, OH) as compared to the least polluted city (Portage, WI). The audit and validation of the Harvard Six Cities Study conducted by the reanalysis team generally confirmed the quality of the data and the numerical results reported by the original investigators. The discrepancies noted during the audit were not of epidemiologic importance, and did not substantively alter the original risk estimates associated with particulate air pollution, nor the main conclusions reached by the original investigators. PMID:16020032

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

    PubMed Central

    Shen, Zhilei Liu; Li, Zong-Ming

    2012-01-01

    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. PMID:22502882

  17. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... laboratory study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Conduct of a nonclinical laboratory study. 58.130... GENERAL GOOD LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Protocol for and Conduct of...

  18. Guidelines for the Design and Conduct of Clinical Studies in Knee Articular Cartilage Repair

    PubMed Central

    Mithoefer, Kai; Saris, Daniel B.F.; Farr, Jack; Kon, Elizaveta; Zaslav, Kenneth; Cole, Brian J.; Ranstam, Jonas; Yao, Jian; Shive, Matthew; Levine, David; Dalemans, Wilfried; Brittberg, Mats

    2011-01-01

    Objective: To summarize current clinical research practice and develop methodological standards for objective scientific evaluation of knee cartilage repair procedures and products. Design: A comprehensive literature review was performed of high-level original studies providing information relevant for the design of clinical studies on articular cartilage repair in the knee. Analysis of cartilage repair publications and synopses of ongoing trials were used to identify important criteria for the design, reporting, and interpretation of studies in this field. Results: Current literature reflects the methodological limitations of the scientific evidence available for articular cartilage repair. However, clinical trial databases of ongoing trials document a trend suggesting improved study designs and clinical evaluation methodology. Based on the current scientific information and standards of clinical care, detailed methodological recommendations were developed for the statistical study design, patient recruitment, control group considerations, study endpoint definition, documentation of results, use of validated patient-reported outcome instruments, and inclusion and exclusion criteria for the design and conduct of scientifically sound cartilage repair study protocols. A consensus statement among the International Cartilage Repair Society (ICRS) and contributing authors experienced in clinical trial design and implementation was achieved. Conclusions: High-quality clinical research methodology is critical for the optimal evaluation of current and new cartilage repair technologies. In addition to generally applicable principles for orthopedic study design, specific criteria and considerations apply to cartilage repair studies. Systematic application of these criteria and considerations can facilitate study designs that are scientifically rigorous, ethical, practical, and appropriate for the question(s) being addressed in any given cartilage repair research project. PMID:26069574

  19. Recent propeller development and studies conducted at ONERA

    NASA Astrophysics Data System (ADS)

    Jouaillec, F.

    Based on recent research, the common interests that exist between aeronautical and naval propeller design is presented. A review of aeronautical propeller evolution up to the introduction of unducted fan technology is offered, along with a history of the marine propeller. Specific areas covered include airflow calculation through Euler three-dimensional methodology, acoustic calculations for discrete-frequency noise of helicopter rotors, and vibration studies of aircraft and ship propellers. Similarity of test results and possible commonality applications for the two propeller types are discussed.

  20. Commitment in different relationships statuses: validation study of the personal commitment scale.

    PubMed

    Monteiro, Ana Pego; Costa-Ramalho, Susana; Ribeiro, Maria Teresa; Pinto, Alexandra Marques

    2015-01-01

    This study presents the validation process of the Portuguese version of the short-form Dedication Scale (Rhoades, Stanley, & Markman, 2006; Stanley, 1986), with a sample of 924 participants in different relationship statutes. With 14 items, this short version is recommended by the authors for its simple use, when wanting to measure commitment in romantic relationships. Confirmatory factor analysis showed that the instrument did not have a totally acceptable fit with the data so an exploratory factor analysis was conducted. This revealed a one-dimensional structure of the scale, and led to the exclusion of two items, which relate to a distinct meta-commitment dimension. In sum, the Portuguese version (ECP - Personal Commitment Scale) has 12 items, with good internal consistency (α = .82), correlations item-total between .36 and .60, and good criteria validity (p < .001). Its use for research is therefore appropriate. In a second study, significant differences were found between the participants' four relationship statuses (dating non-cohabiting and cohabiting relationships, formal unions and marriage) (p < .001; η2 p = .03). Results showed that married participants were more committed than those in a formal union, even when controlling for several relational and socio-demographic variables. No differences were found between cohabiting and non-cohabiting dating participants. Men reported higher levels of commitment than women (p < .001; η2 p = .02). Implications and suggestions for future research are discussed. PMID:26037376

  1. A Validation Study of Merging and Spacing Techniques in a NAS-Wide Simulation

    NASA Technical Reports Server (NTRS)

    Glaab, Patricia C.

    2011-01-01

    In November 2010, Intelligent Automation, Inc. (IAI) delivered an M&S software tool to that allows system level studies of the complex terminal airspace with the ACES simulation. The software was evaluated against current day arrivals in the Atlanta TRACON using Atlanta's Hartsfield-Jackson International Airport (KATL) arrival schedules. Results of this validation effort are presented describing data sets, traffic flow assumptions and techniques, and arrival rate comparisons between reported landings at Atlanta versus simulated arrivals using the same traffic sets in ACES equipped with M&S. Initial results showed the simulated system capacity to be significantly below arrival capacity seen at KATL. Data was gathered for Atlanta using commercial airport and flight tracking websites (like FlightAware.com), and analyzed to insure compatible techniques were used for result reporting and comparison. TFM operators for Atlanta were consulted for tuning final simulation parameters and for guidance in flow management techniques during high volume operations. Using these modified parameters and incorporating TFM guidance for efficiencies in flowing aircraft, arrival capacity for KATL was matched for the simulation. Following this validation effort, a sensitivity study was conducted to measure the impact of variations in system parameters on the Atlanta airport arrival capacity.

  2. The Validity of Oral Accommodation in Testing: NAEP Validity Studies. Working Paper Series.

    ERIC Educational Resources Information Center

    Weston, Timothy J.

    This study examined the impact of oral presentation of a mathematics test on the performance of disabled and nondisabled students. Sixty-five learning disabled and 54 nondisabled fourth graders took two matched forms of a mathematics assessment based on National Assessment of Educational Progress (NAEP) items. Order of presentation for the…

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

    SciTech Connect

    Smolen, G.R.; Matsumoto, T. )

    1989-01-01

    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).

  4. Tracking Study for Top-off Safety Validation at SSRL

    SciTech Connect

    Huang, X.; Bauer, J.; Corbett, J.; Dell'Orco, D.; Hettel, B.; Liu, J.; Rabedeau, T.; Safranek, J.; Schmerge, J.; Sebek, J.; Tanabe, J.; Terebilo, A.; Wang, L.; ,

    2011-08-19

    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.

  5. Mössbauer spectroscopy studies of selected conducting polypyrroles

    NASA Astrophysics Data System (ADS)

    Proń, A.; Kucharski, Z.; Budrowski, C.; Zagórska, M.; Krichene, S.; Suwalski, J.; Dehe, G.; Lefrant, S.

    1985-12-01

    Polypyrrole obtained by chemical oxidation of pyrrole in ethanol-water solution containing FeCl3 can be reduced chemically in Na+Naph-/THF solution and then reoxidized with FeCl3, SnCl4, and SbCl5. 57Fe and 119Sn Mössbauer spectra of the reaction products show only one type of iron and tin with Mössbauer parameters characteristic of FeCl-4 and SnCl-5. In the case of the oxidation with SbCl5, two nonequivalent antimony nuclei have been detected by 121Sb. The calculated isomer shift and quadrupole splitting values are consistent with SbCl-6 and SbCl3. The resonant absorption in all three systems studied is strongly temperature dependent and can be observed only at temperatures significantly lower than RT. This behavior indicates a low Mössbauer lattice temperature and an extremely loose bonding between the inserted anions and polymer chains.

  6. Probabilistic Study Conducted on Sensor-Based Engine Life Calculation

    NASA Technical Reports Server (NTRS)

    Guo, Ten-Huei

    2004-01-01

    Turbine engine life management is a very complicated process to ensure the safe operation of an engine subjected to complex usage. The challenge of life management is to find a reasonable compromise between the safe operation and the maximum usage of critical parts to reduce maintenance costs. The commonly used "cycle count" approach does not take the engine operation conditions into account, and it oversimplifies the calculation of the life usage. Because of the shortcomings, many engine components are regularly pulled for maintenance before their usable life is over. And, if an engine has been running regularly under more severe conditions, components might not be taken out of service before they exceed their designed risk of failure. The NASA Glenn Research Center and its industrial and academic partners have been using measurable parameters to improve engine life estimation. This study was based on the Monte Carlo simulation of 5000 typical flights under various operating conditions. First a closed-loop engine model was developed to simulate the engine operation across the mission profile and a thermomechanical fatigue (TMF) damage model was used to calculate the actual damage during takeoff, where the maximum TMF accumulates. Next, a Weibull distribution was used to estimate the implied probability of failure for a given accumulated cycle count. Monte Carlo simulations were then employed to find the profiles of the TMF damage under different operating assumptions including parameter uncertainties. Finally, probabilities of failure for different operating conditions were analyzed to demonstrate the importance of a sensor-based damage calculation in order to better manage the risk of failure and on-wing life.

  7. Parametric Study Conducted of Rocket- Based, Combined-Cycle Nozzles

    NASA Technical Reports Server (NTRS)

    Steffen, Christopher J., Jr.; Smith, Timothy D.

    1998-01-01

    Having reached the end of the 20th century, our society is quite familiar with the many benefits of recycling and reusing the products of civilization. The high-technology world of aerospace vehicle design is no exception. Because of the many potential economic benefits of reusable launch vehicles, NASA is aggressively pursuing this technology on several fronts. One of the most promising technologies receiving renewed attention is Rocket-Based, Combined-Cycle (RBCC) propulsion. This propulsion method combines many of the efficiencies of high-performance jet aircraft with the power and high-altitude capability of rocket engines. The goal of the present work at the NASA Lewis Research Center is to further understand the complex fluid physics within RBCC engines that govern system performance. This work is being performed in support of NASA's Advanced Reusable Technologies program. A robust RBCC engine design optimization demands further investigation of the subsystem performance of the engine's complex propulsion cycles. The RBCC propulsion system under consideration at Lewis is defined by four modes of operation in a singlestage- to-orbit configuration. In the first mode, the engine functions as a rocket-driven ejector. When the rocket engine is switched off, subsonic combustion (mode 2) is present in the ramjet mode. As the vehicle continues to accelerate, supersonic combustion (mode 3) occurs in the ramjet mode. Finally, as the edge of the atmosphere is approached and the engine inlet is closed off, the rocket is reignited and the final accent to orbit is undertaken in an all-rocket mode (mode 4). The performance of this fourth and final mode is the subject of this present study. Performance is being monitored in terms of the amount of thrust generated from a given amount of propellant.

  8. Oxygen flux and dielectric response study of Mixed Ionic-Electronic Conducting (MIEC) heterogeneous functional materials

    NASA Astrophysics Data System (ADS)

    Rabbi, Fazle

    Dense mixed ionic-electronic conducting (MIEC) membranes consisting of ionic conductive perovskite-type and/or fluorite-type oxides and high electronic conductive spinel type oxides, at elevated temperature can play a useful role in a number of energy conversion related systems including the solid oxide fuel cell (SOFC), oxygen separation and permeation membranes, partial oxidization membrane reactors for natural gas processing, high temperature electrolysis cells, and others. This study will investigate the impact of different heterogeneous characteristics of dual phase ionic and electronic conductive oxygen separation membranes on their transport mechanisms, in an attempt to develop a foundation for the rational design of such membranes. The dielectric behavior of a material can be an indicator for MIEC performance and can be incorporated into computational models of MIEC membranes in order to optimize the composition, microstructure, and ultimately predict long term membrane performance. The dielectric behavior of the MIECs can also be an indicator of the transport mechanisms and the parameters they are dependent upon. For this study we chose a dual phase MIEC oxygen separation membrane consisting of an ionic conducting phase: gadolinium doped ceria-Ce0.8 Gd0.2O2 (GDC) and an electronic conductive phase: cobalt ferrite-CoFe2O4 (CFO). The membranes were fabricated from mixtures of Nano-powder of each of the phases for different volume percentages, sintered with various temperatures and sintering time to form systematic micro-structural variations, and characterized by structural analysis (XRD), and micro-structural analysis (SEM-EDS). Performance of the membranes was tested for variable partial pressures of oxygen across the membrane at temperatures from 850°C-1060°C using a Gas Chromatography (GC) system. Permeated oxygen did not directly correlate with change in percent mixture. An intermediate mixture 60%GDC-40%CFO had the highest flux compared to the 50%GDC-50%CFO and 80%GDC-20%CFO mixtures. Material characterization suggests the emergence of a third phase contributing to the behavior. Microstructural studies suggested changes in micro-structure of a given volume fraction for different sintering temperature and sintering time. Flux variation was observed for membranes with the same constituent volume fraction but different micro-structure indicating the effects of the micro-structure on the overall oxygen permeation. To correlate the experimental flux measurement with a standard Wagner's flux equation, different microstructural characteristics were studied to incorporate them into a modified Wagner's flux equation. In-situ broadband dielectric spectroscopy measurements over a temperature range of 850°C-1060°C and frequency range of (0.1Hz-1MHz) of the operating 60%GDC-40%CFO mixture oxygen separation membranes were measured using a NOVOCONTROL dielectric spectroscopy test system. Dielectric response of the operating membrane was studied to identify the charge transfer process in the membrane. A computational model to study the dielectric impedance response of different microstructure was developed using a COMSOL(TM) Multiphysics qasi-static electromagnetic module. This model was validated using model materials with regular geometric shapes. To measure impedance of real micro/nano-structures of the membrane material, domains required for the COMSOL calculation were obtained from actual micro/nano structures by using 3D scans from X-ray nano and micro tomography. Simpleware(TM) software was used to generate 3D domains from image slices obtained from the 3D x-ray scans. Initial voltage distributions on the original microstructure were obtained from the computational model. Similarly, development of a primary model for simulating ionic/electronic species flow inside of an MIEC was also begun. The possibility of using broadband dielectric spectroscopy methods to understand and anticipate the flux capabilities of MIECs to reduce the cost and time of development of such material systems was explored.

  9. Validity of Internet-Based Longitudinal Study Data: The Elephant in the Virtual Room

    PubMed Central

    Summers, Kim M; Bronsvoort, B Mark C; Handel, Ian G; Clements, Dylan N

    2015-01-01

    Background Internet-based data collection relies on well-designed and validated questionnaires. The theory behind designing and validating questionnaires is well described, but few practical examples of how to approach validation are available in the literature. Objective We aimed to validate data collected in an ongoing Internet-based longitudinal health study through direct visits to participants and recall of their health records. We demonstrate that despite extensive pre-planning, social desirability can still affect data in unexpected ways and that anticipation of poor quality data may be confounded by positive validation. Methods Dogslife is a large-scale, Web-based longitudinal study of canine health, in which owners of Labrador Retrievers were recruited and questioned at regular intervals about the lifestyle and health of their dogs using an Internet-based questionnaire. The Dogslife questionnaire predominantly consists of closed-answer questions. In our work, two separate validation methodologies were used: (1) direct interviews with 43 participants during visits to their households and (2) comparison of owner-entered health reports with 139 historical health records. Results Our results indicate that user-derived measures should not be regarded as a single category; instead, each measurement should be considered separately as each presents its own challenge to participants. We recommend trying to ascertain the extent of recall decay within a study and, if necessary, using this to guide data collection timepoints and analyses. Finally, we recommend that multiple methods of communication facilitate validation studies and aid cohort engagement. Conclusions Our study highlighted how the theory underpinning online questionnaire design and validation translates into practical data issues when applied to Internet-based studies. Validation should be regarded as an extension of questionnaire design, and that validation work should commence as soon as sufficient data are available. We believe that validation is a crucial step and hope our suggested guidelines will help facilitate validation of other Internet-based cohort studies. PMID:25887101

  10. An Experimental Study of Characteristic Combustion-Driven Flow for CFD Validation

    NASA Technical Reports Server (NTRS)

    Santoro, Robert J.

    1997-01-01

    A series of uni-element rocket injector studies were completed to provide benchmark quality data needed to validate computational fluid dynamic models. A shear coaxial injector geometry was selected as the primary injector for study using gaseous hydrogen/oxygen and gaseous hydrogen/liquid oxygen propellants. Emphasis was placed on the use of non-intrusive diagnostic techniques to characterize the flowfields inside an optically-accessible rocket chamber. Measurements of the velocity and species fields were obtained using laser velocimetry and Raman spectroscopy, respectively Qualitative flame shape information was also obtained using laser-induced fluorescence excited from OH radicals and laser light scattering studies of aluminum oxide particle seeded combusting flows. The gaseous hydrogen/liquid oxygen propellant studies for the shear coaxial injector focused on breakup mechanisms associated with the liquid oxygen jet under sub-critical pressure conditions. Laser sheet illumination techniques were used to visualize the core region of the jet and a Phase Doppler Particle Analyzer was utilized for drop velocity, size and size distribution characterization. The results of these studies indicated that the shear coaxial geometry configuration was a relatively poor injector in terms of mixing. The oxygen core was observed to extend well downstream of the injector and a significant fraction of the mixing occurred in the near nozzle region where measurements were not possible to obtain Detailed velocity and species measurements were obtained to allow CFD model validation and this set of benchmark data represents the most comprehensive data set available to date As an extension of the investigation, a series of gas/gas injector studies were conducted in support of the X-33 Reusable Launch Vehicle program. A Gas/Gas Injector Technology team was formed consisting of the Marshall Space Flight Center, the NASA Lewis Research Center, Rocketdyne and Penn State. Injector geometries studied under this task included shear and swirl coaxial configurations as well as an impinging jet injector.

  11. An Experimental Study of Characteristic Combustion-Driven Flow for CFD Validation

    NASA Technical Reports Server (NTRS)

    Santoro, Robert J.

    1997-01-01

    A series of uni-element rocket injector studies were completed to provide benchmark quality data needed to validate computational fluid dynamic models. A shear coaxial injector geometry was selected as the primary injector for study using gaseous hydrogen/oxygen and gaseous hydrogen/liquid oxygen propellants. Emphasis was placed on the use of nonintrusive diagnostic techniques to characterize the flowfields inside an optically-accessible rocket chamber. Measurements of the velocity and species fields were obtained using laser velocimetry and Raman spectroscopy, respectively. Qualitative flame shape information was also obtained using laser-induced fluorescence excited from OH radicals and laser light scattering studies of aluminum oxide particle seeded combusting flows. The gaseous hydrogen/liquid oxygen propellant studies for the shear coaxial injector focused on breakup mechanisms associated with the liquid oxygen jet under subcritical pressure conditions. Laser sheet illumination techniques were used to visualize the core region of the jet and a Phase Doppler Particle Analyzer was utilized for drop velocity, size and size distribution characterization. The results of these studies indicated that the shear coaxial geometry configuration was a relatively poor injector in terms of mixing. The oxygen core was observed to extend well downstream of the injector and a significant fraction of the mixing occurred in the near nozzle region where measurements were not possible to obtain. Detailed velocity and species measurements were obtained to allow CFD model validation and this set of benchmark data represents the most comprehensive data set available to date. As an extension of the investigation, a series of gas/gas injector studies were conducted in support of the X-33 Reusable Launch Vehicle program. A Gas/Gas Injector Technology team was formed consisting of the Marshall Space Flight Center, the NASA Lewis Research Center, Rocketdyne and Penn State. Injector geometries studied under this task included shear and swirl coaxial configurations as well as an impinging jet injector.

  12. Trials and tribulations of conducting interventional studies in urban slums of a developing country: Experiences from Kolkata, India.

    PubMed

    Mahapatra, Tanmay; Mahapatra, Sanchita; Pal, Debottam; Saha, Jayanta; Lopez, AnnaLena; Ali, Mohammad; Bannerjee, Barnali; Manna, Byomkesh; Sur, Dipika; Bhattacharya, Sujit; Kanungo, Suman

    2016-01-01

    Experimental studies involving human subjects provide most internally valid evidences in epidemiological research due to their robust methodology. While conducting population-based interventional studies, to achieve external validity, inclusion of information from vulnerable groups like urban slum-dwellers of the developing world, in the epidemiological estimates is of paramount importance. The challenges faced while conducting 2 consecutive large-scale, community-based vaccine trials in urban slums of Kolkata, India are presented in this article. Interventions in these communities often get constrained by issues pertaining to human rights and benefits, socio-cultural factors, political environment, methodological shortcomings in addition to the challenges in ensuring community participation. While conducting these trials although we intermittently faced obstacles, by virtue of having a long term and robust surveillance system and developing a trusted relationship between the researchers, community leaders and residents we were able to come up with a commendable community participation which culminated into the success of the interventions. Bridging the gap between research and field operations by incorporating knowledge gathered from interventional studies and making strategies to improve health conditions of these informal settlers is a major unfulfilled agenda. We believe the lessons learnt during our research will help researchers while developing efficient interventions in similar setting. PMID:26224251

  13. Comparative Study in Laboratory Rats to Validate Sperm Quality Methods and Endpoints

    NASA Technical Reports Server (NTRS)

    Price, W. A.; Briggs, G. B.; Alexander, W. K.; Still, K. R.; Grasman, K. A.

    2000-01-01

    Abstract The Naval Health Research Center, Detachment (Toxicology) performs toxicity studies in laboratory animals to characterize the risk of exposure to chemicals of Navy interest. Research was conducted at the Toxicology Detachment at WPAFB, OH in collaboration with Wright State University, Department of Biological Sciences for the validation of new bioassay methods for evaluating reproductive toxicity. The Hamilton Thorne sperm analyzer was used to evaluate sperm damage produced by exposure to a known testicular toxic agent, methoxyacetic acid and by inhalation exposure to JP-8 and JP-5 in laboratory rats. Sperm quality parameters were evaluated (sperm concentration, motility, and morphology) to provide evidence of sperm damage. The Hamilton Thorne sperm analyzer utilizes a DNA specific fluorescent stain (similar to flow cytometry) and digitized optical computer analysis to detect sperm cell damage. The computer assisted sperm analysis (CASA) is a more rapid, robust, predictive and sensitive method for characterizing reproductive toxicity. The results presented in this poster report validation information showing exposure to methoxyacetic acid causes reproductive toxicity and inhalation exposure to JP-8 and JP-5 had no significant effects. The CASA method detects early changes that result in reproductive deficits and these data will be used in a continuing program to characterize the toxicity of chemicals, and combinations of chemicals, of military interest to formulate permissible exposure limits.

  14. Studying Atmospheric Dynamics- Validation of ADM- Aeolus Wind LIDAR Observations

    NASA Astrophysics Data System (ADS)

    Reitebuch, Oliver; Marksteiner, Uwe; Witschas, Benjamin; Lemmerz, Christian; Wu, Songhua; Liu, Zhishen

    2014-11-01

    For many years now the need for adequate global measurements of wind profiles at all altitude levels remains at highest priority. A space-borne system using the LIDAR (LIght Detection And Ranging) technology is deemed to fill the current gap of wind observations. Therefore, the European Space Agency (ESA) initiated the Atmospheric Dynamics Mission (ADM) including the Aeolus satellite which will be launched end of 2015. In order to support the pre-launch validation, the A2D, an airborne prototype of the satellite instrument was developed by DLR (Deutsches Zentrum für Luft- und Raumfahrt). In the past the A2D has been deployed on the DLR Falcon aircraft several times. In this paper results are reported from an airborne campaign in 2009 and recent laboratory measurements involving the A2D.

  15. Quantum mechanics concept assessment: Development and validation study

    NASA Astrophysics Data System (ADS)

    Sadaghiani, Homeyra R.; Pollock, Steven J.

    2015-06-01

    As part of an ongoing investigation of students' learning in first semester upper-division quantum mechanics, we needed a high-quality conceptual assessment instrument for comparing outcomes of different curricular approaches. The process of developing such a tool started with converting a preliminary version of a 14-item open-ended quantum mechanics assessment tool (QMAT) to a multiple-choice (MC) format. Further question refinement, development of effective distractors, adding new questions, and robust statistical analysis has led to a 31-item quantum mechanics concept assessment (QMCA) test. The QMCA is used as post-test only to assess students' knowledge about five main topics of quantum measurement: the time-independent Schrödinger equation, wave functions and boundary conditions, time evolution, and probability density. During two years of testing and refinement, the QMCA has been given in alpha (N =61 ) and beta versions (N =263 ) to students in upper division quantum mechanics courses at 11 different institutions with an average post-test score of 54%. By allowing for comparisons of student learning across different populations and institutions, the QMCA provides instructors and researchers a more standard measure of effectiveness of different curricula or teaching strategies on student conceptual understanding of quantum mechanics. In this paper, we discuss the construction of effective distractors and the use of student interviews and expert feedback to revise and validate both questions and distractors. We include the results of common statistical tests of reliability and validity, which suggest the instrument is presently in a stable, usable, and promising form.

  16. Teacher Evaluation Project. The Beginning Teacher Program, Intellectual Skills Development, Validity Studies of the Evaluation System, Special Instrument Development. Report for 1984-1985.

    ERIC Educational Resources Information Center

    Florida Coalition for the Development of a Performance Measurement System, Tallahassee.

    Reports, summaries, and recommendations are presented on the following research studies: (1) Beginning Teacher Studies; (2) Instructional Skills for Teaching Higher Order Thinking; (3) Development of the Conferential Observation Instrument; (4) Predictive Validity Studies Conducted to Test the Relationship Between Teacher Performance as Measured…

  17. Signs and symptoms versus nerve conduction studies to diagnose diabetic sensorimotor polyneuropathy: Cl vs. NPhys trial.

    PubMed

    Dyck, Peter J; Overland, Carol J; Low, Phillip A; Litchy, William J; Davies, Jenny L; Dyck, P James B; O'Brien, Peter C; Albers, James W; Andersen, Henning; Bolton, Charles F; England, John D; Klein, Christopher J; Llewelyn, J Gareth; Mauermann, Michelle L; Russell, James W; Singer, Wolfgang; Smith, A Gordon; Tesfaye, Solomon; Vella, Adrian

    2010-08-01

    The purpose was to test whether physicians can validly and reproducibly diagnose diabetic sensorimotor polyneuropathy (DSPN). 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 (dx) and a nerve conduction score (Sigma5 NC nds). Masking of patients was achieved. Reproducibility measured by the kappa coefficient and compared to Sigma5 NC nd varied considerably among physicians: median and ranges: signs 0.8 (0.32-1.0); symptoms 0.79 (0.36-1.0), and diagnoses 0.47 (0.33-0.84), both low and high scores indicating poor performance. There was substantial agreement between 75% group dx and confirmed NC abnormality (abn). As compared to Sigma5 NC, individual physicians' clinical dx was excessively variable and frequently inaccurate. Study physician dx from signs and symptoms were excessively variable, often overestimating DSPN. Specific approaches to improving clinical proficiency should be tested. PMID:20658599

  18. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false How will a feasibility study be conducted... BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Feasibility Studies § 404.47 How will a feasibility study be conducted under this program? Feasibility studies will...

  19. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false How will a feasibility study be conducted... BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Feasibility Studies § 404.47 How will a feasibility study be conducted under this program? Feasibility studies will...

  20. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Conduct of a nonclinical laboratory study. 58.130... Nonclinical Laboratory Study § 58.130 Conduct of a nonclinical laboratory study. (a) The...

  1. Strategies to assess the validity of recommendations: a study protocol

    PubMed Central

    2013-01-01

    Background Clinical practice guidelines (CPGs) become quickly outdated and require a periodic reassessment of evidence research to maintain their validity. However, there is little research about this topic. Our project will provide evidence for some of the most pressing questions in this field: 1) what is the average time for recommendations to become out of date?; 2) what is the comparative performance of two restricted search strategies to evaluate the need to update recommendations?; and 3) what is the feasibility of a more regular monitoring and updating strategy compared to usual practice?. In this protocol we will focus on questions one and two. Methods The CPG Development Programme of the Spanish Ministry of Health developed 14 CPGs between 2008 and 2009. We will stratify guidelines by topic and by publication year, and include one CPG by strata. We will develop a strategy to assess the validity of CPG recommendations, which includes a baseline survey of clinical experts, an update of the original exhaustive literature searches, the identification of key references (reference that trigger a potential recommendation update), and the assessment of the potential changes in each recommendation. We will run two alternative search strategies to efficiently identify important new evidence: 1) PLUS search based in McMaster Premium LiteratUre Service (PLUS) database; and 2) a Restrictive Search (ReSe) based on the least number of MeSH terms and free text words needed to locate all the references of each original recommendation. We will perform a survival analysis of recommendations using the Kaplan-Meier method and we will use the log-rank test to analyse differences between survival curves according to the topic, the purpose, the strength of recommendations and the turnover. We will retrieve key references from the exhaustive search and evaluate their presence in the PLUS and ReSe search results. Discussion Our project, using a highly structured and transparent methodology, will provide guidance of when recommendations are likely to be at risk of being out of date. We will also assess two novel restrictive search strategies which could reduce the workload without compromising rigour when CPGs developers check for the need of updating. PMID:23967896

  2. EGFR mutation detection by microfluidic technology: a validation study.

    PubMed

    Malapelle, Umberto; Russo, Stefania; Pepe, Francesco; Sgariglia, Roberta; De Luca, Caterina; Bellevicine, Claudio; Pallante, Pierlorenzo; Troncone, Giancarlo

    2013-11-01

    Advanced non-small cell lung cancer samples are tested for epidermal growth factor receptor (EGFR) gene mutations. Their detection by direct sequencing is time-consuming. Conversely, the length analysis of fluorescently labelled PCR products is easier. To avoid labelled primers and the automated capillary electrophoresis apparatus, we validated a fast and sensitive chip-based microfluidic technology. The limit of detection of fragment length assay on microfluidic device was 5%, more sensitive than direct sequencing (12.5%). The novel methodology showed high accuracy in the analysis of samples whose mutational status was known. The accuracy in quantifying mutated alleles (mA) was evaluated by PCR products subcloning; the mA% provided by direct sequencing of subcloned PCR products showed a close correlation with the mA% provided by the microfluidic technology for both exon 19 (R(2)=0.9) and 21 (R(2)=0.9). Microfluidic-based on-chip electrophoresis makes EGFR testing more rapid, sensitive and cost-effective. PMID:23794480

  3. Quality Rating and Improvement System (QRIS) Validation Study Designs. CEELO FastFacts

    ERIC Educational Resources Information Center

    Schilder, D.

    2013-01-01

    In this "Fast Facts," a state has received Race to the Top Early Learning Challenge funds and is seeking information to inform the design of the Quality Rating and Improvement System (QRIS) validation study. The Center on Enhancing Early Learning Outcomes (CEELO) responds that according to Resnick (2012), validation of a QRIS is an…

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

    ERIC Educational Resources Information Center

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

    2009-01-01

    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…

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

    ERIC Educational Resources Information Center

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

    2002-01-01

    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…

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

    ERIC Educational Resources Information Center

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

    2012-01-01

    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…

  7. Improved Diagnostic Validity of the ADOS Revised Algorithms: A Replication Study in an Independent Sample

    ERIC Educational Resources Information Center

    Oosterling, Iris; 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

    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…

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

    ERIC Educational Resources Information Center

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

    2012-01-01

    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

  9. The Validity of the Achievement-Orientation Model for Gifted Middle School Students: An Exploratory Study

    ERIC Educational Resources Information Center

    Ritchotte, Jennifer A.; Matthews, Michael S.; Flowers, Claudia P.

    2014-01-01

    Gifted underachievement represents a frustrating loss of potential for society. Although attempts have been made to develop interventions to reverse gifted underachievement, the theoretical underpinnings of these interventions have yet to be empirically validated. The purpose of this study was to investigate the validity of the…

  10. A Study of the Criterion Validity of the Mattis Dementia Rating Scale.

    ERIC Educational Resources Information Center

    Fernandez, Alberto Luis; Scheffel, Debora L.

    2003-01-01

    Evaluated the criterion validity of the Mattis Dementia Rating Scale (S. Mattis, 1988) with a concurrent study to obtain a cut-off score for an Argentinean population by administering a battery of tests to 60 memory disorder patients. Findings demonstrate high convergent validity with another measure and show an appropriate cut score for use with…

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

    ERIC Educational Resources Information Center

    Bozdogan, Aykut Emre

    2011-01-01

    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…

  12. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Conduct of a nonclinical laboratory study. 58.130 Section 58.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Nonclinical Laboratory Study § 58.130 Conduct of a nonclinical laboratory study. (a) The...

  13. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... GENERAL GOOD LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Protocol for and Conduct of a... laboratory study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature,...

  14. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... GENERAL GOOD LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Protocol for and Conduct of a... laboratory study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature,...

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

    SciTech Connect

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

    2013-01-01

    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.

  16. 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

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

    2011-01-01

    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…

  17. Assessing Households Preparedness for Earthquakes: An Exploratory Study in the Development of a Valid and Reliable Persian-version Tool

    PubMed Central

    Ardalan, Ali; Sohrabizadeh, Sanaz

    2016-01-01

    Introduction: Iran is placed among countries suffering from the highest number of earthquake casualties. Household preparedness, as one component of risk reduction efforts, is often supported in quake-prone areas. In Iran, lack of a valid and reliable household preparedness tool was reported by previous disaster studies. This study is aimed to fill this gap by developing a valid and reliable tool for assessing household preparedness in the event of an earthquake. Methods: This survey was conducted through three phases including literature review and focus group discussions with the participation of eight key informants, validity measurements and reliability measurements. Field investigation was completed with the participation of 450 households within three provinces of Iran. Content validity, construct validity, the use of factor analysis; internal consistency using Cronbach's alpha coefficient, and test-retest reliability were carried out to develop the tool. Results: Based on the CVIs, ranging from 0.80 to 0.100, and exploratory factor analysis with factor loading of more than 0.5, all items were valid. The amount of Cronbach's alpha (0.7) and test-retest examination by Spearman correlations indicated that the scale was also reliable. The final instrument consisted of six categories and 18 questions including actions at the time of earthquakes, nonstructural safety, structural safety, hazard map, communications, drill, and safety skills. Conclusion: Using a Persian-version tool that is adjusted to the socio-cultural determinants and native language may result in more trustful information on earthquake preparedness. It is suggested that disaster managers and researchers apply this tool in their future household preparedness projects. Further research is needed to make effective policies and plans for transforming preparedness knowledge into behavior. PMID:26981326

  18. Validation of a susceptibility, benefits, and barrier scale for mammography screening among Peruvian women: a cross-sectional study

    PubMed Central

    2011-01-01

    Background Perceived beliefs about breast cancer and breast cancer screening are important predictors for mammography utilization. This study adapted and validated the Champion's scale in Peru. This scale measures perceived susceptibility for breast cancer and perceived benefits and barriers for mammography. Methods A cross-sectional study was conducted among women ages 40 to 65 attending outpatient gynecology services in a public hospital in Peru. A group of experts developed and pre-tested a Spanish version of the Champion's scale to assess its comprehensibility (N = 20). Factor analysis, internal consistency, and test-retest reliability analyses were performed (N = 285). Concurrent validity compared scores from participants who had a mammogram and those who did not have it in the previous 15 months. T-test and multiple regression analysis adjusting for socio-demographic factors, mammography knowledge and other preventive behaviors were performed. Results The construct validity and reliability were optimal. Cronbach-Alpha coefficients were 0.75 (susceptibility), 0.72 (benefits) and 0.86 (barriers). Concurrent validity analysis showed an association between barriers and mammography screening use in bivariate (22.3 ± 6.7 vs. 30.2 ± 7.6; p < 0.001) and multiple regression analysis (OR = 0.28, 95% CI = 0.18-0.43). Ages 50-60 years (OR = 2.35, 95% CI = 1.19-4.65), history of prior Papanicolaou test (OR = 3.69, 95% CI = 1.84-7.40), and knowledge about breast cancer and mammography (OR = 3.69, 95% CI = 1.84-7.40) were also independently associated with mammography screening use. Conclusion Concurrent validity analysis showed that the Champion's scale has important limitations for assessing perceived susceptibility for breast cancer and perceived benefits for mammography among Peruvian women. There is still a need for developing valid and reliable instruments for measuring perceived beliefs about breast cancer and mammography screening among Peruvian women. PMID:22145936

  19. Electric field studies: TLE-induced waveforms and ground conductivity impact on electric field propagation

    NASA Astrophysics Data System (ADS)

    Farges, Thomas; Garcia, Geraldine; Blanc, Elisabeth

    2010-05-01

    We review in this paper main results obtained from electric field (from VLF to HF) measurement campaigns realized by CEA in the framework of the Eurosprite program [Neubert et al., 2005, 2008] from 2003 to 2009 in France in different configurations. Two main topics have been studied: sprite or elve induced phenomena (radiation or perturbation) and wave propagation. Using a network of 4 stations, VLF radiations from sprite have been successfully located at 10 km from the sprite parent lightning, in agreement with possible sprite location, generally displaced from the parent lightning. The MF (300 kHz - 3 MHz) source bursts were identified simultaneously with the occurrence of sprites observed with cameras [Farges et al., 2004; Neubert et al., 2008]. These observations are compared to recent broadband measurements, assumed to be due to relativistic electron beam radiation related to sprites [Fullekrug et al., 2009]. Recently, in 2009, with a new instrumentation, an ELF tail has been clearly measured after the lightning waveform, while sprites were observed at about 500 km from our station. This ELF tail is usually observed at distances higher than thousand km and is associated to sprite generation. This opens the capacity to measure the charge moment of the parent-lightning, using such measurement close to the source. Farges et al. [2007] showed that just after a lightning return stroke, a strong transient attenuation is very frequently observed in the MF waves of radio transmissions. They showed that this perturbation is due to heating of the lower ionosphere by the lightning-induced EMP during few milliseconds. These perturbations are then the MF radio signature of the lightning EMP effects on the lower ionosphere, in the same way as elves correspond to their optical signature. The experiment also provided the electric field waveforms directly associated to elves, while lightning were not detected by Météorage. Many of them present a double peak feature. The propagation of the electromagnetic waves generated by lightning has also been studied in the frequency range 1 kHz-1MHz at distances lower than 1000 km from the lightning source. A propagation model has been developed to determine the ground waves which propagate in a homogenous medium using the analytical expression given by Maclean and Wu [1993]. This approach takes into account the electric finite conductivity and the fact that the Earth is spherical, which allow us to deal with over-the-horizon propagation. We installed in 2008 four stations which were more or less aligned - the maximum distance between two stations was about 870 km. Two stations were located close to the Mediterranean Sea and the two others inside the continent, at the centre of France. This station distribution and the observation period (from August to December) allowed statistical and physical studies, such as the influence of the electric conductivity on wave propagation. Comparison of electric field spectra, measured after propagation only over sea and only over ground, showed clearly the effects of ground conductivity on propagation. Comparison between observations and modelling has been used to evaluate the ground conductivity. In the future we will implement the sky-wave inside our model and validate it with the database.

  20. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Overview § 404.18 How can I request assistance to conduct a feasibility study? To request assistance to conduct a feasibility...

  1. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Overview § 404.18 How can I request assistance to conduct a feasibility study? To request assistance to conduct a feasibility...

  2. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Foreign clinical studies not conducted under an IND. 312.120 Section 312.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Miscellaneous § 312.120 Foreign clinical studies not conducted...

  3. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Foreign clinical studies not conducted under an IND. 312.120 Section 312.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Miscellaneous § 312.120 Foreign clinical studies not conducted...

  4. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Foreign clinical studies not conducted under an IND. 312.120 Section 312.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Miscellaneous § 312.120 Foreign clinical studies not conducted...

  5. A validity and reliability study investigating the Turkish version of the Infant Colic Scale.

    PubMed

    Cetinkaya, Bengü; Başbakkal, Zümrüt

    2007-01-01

    The Infant Colic Scale is used to diagnose colic and to determine factors that cause colic. This study aimed to establish the validity and reliability of the Infant Colic Scale for the Turkish population. The research sample included mothers (N = 110) of 132 infants with colic registered at three public health clinics in the Denizli province. Language validity, content validity, and construct validity were examined. On the basis of the Infant Colic Scale's internal consistency reliability analysis, three items were removed. Factor analysis resulted in five subscales. The Cronbach's alpha coefficients were .55 to .89 for the subscales, and .73 for the total scale. The scale's test-retest reliability was .65. The Infant Colic Scale was found to be a valid and reliable measurement tool for the Turkish population. PMID:17440307

  6. ECVAM's research and validation activities in the fields of topical toxicity and human studies.

    PubMed

    Zuang, Valérie

    2002-12-01

    This paper outlines the research, prevalidation and validation activities that ECVAM has undertaken in collaboration with its partners in the field of topical toxicity testing and human volunteer studies, from its creation until now (1994-2002). PMID:12513662

  7. Book Reading Motivation Scale: Reliability and Validity Study

    ERIC Educational Resources Information Center

    Katranci, Mehmet

    2015-01-01

    Book reading enhances the intellectual world of people. It is very important to know the factors that motivate children to read books as it will help to instill book reading habit in them. As such, the present study aims to develop a "Book Reading Motivation Scale" to determine elementary and secondary school students' reading…

  8. Unmasking the Capability of Strategic Learning: A Validation Study

    ERIC Educational Resources Information Center

    Siren, Charlotta A.

    2012-01-01

    Purpose: The strategic learning perspective has attracted increased interest among strategic management scholars, yet the operationalisation of this concept is still in its infancy. The aim of this study is to develop a multidimensional understanding of the strategic learning process and to build an instrument to measure this concept.…

  9. Book Reading Motivation Scale: Reliability and Validity Study

    ERIC Educational Resources Information Center

    Katranci, Mehmet

    2015-01-01

    Book reading enhances the intellectual world of people. It is very important to know the factors that motivate children to read books as it will help to instill book reading habit in them. As such, the present study aims to develop a "Book Reading Motivation Scale" to determine elementary and secondary school students' reading

  10. Virtual Environment Interpersonal Trust Scale: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Usta, Ertugrul

    2012-01-01

    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…

  11. Evaluating the Reliability, Validity, and Usefulness of Education Cost Studies

    ERIC Educational Resources Information Center

    Baker, Bruce D.

    2006-01-01

    Recent studies that purport to estimate the costs of constitutionally adequate education have been described as either a "gold standard" that should guide legislative school finance policy design and judicial evaluation, or as pure "alchemy." Methods for estimating the cost of constitutionally adequate education can be roughly divided into two…

  12. Unmasking the Capability of Strategic Learning: A Validation Study

    ERIC Educational Resources Information Center

    Siren, Charlotta A.

    2012-01-01

    Purpose: The strategic learning perspective has attracted increased interest among strategic management scholars, yet the operationalisation of this concept is still in its infancy. The aim of this study is to develop a multidimensional understanding of the strategic learning process and to build an instrument to measure this concept.

  13. Theoretical Evaluation Self-Test (Test): A Preliminary Validation Study

    ERIC Educational Resources Information Center

    Coleman, Daniel

    2004-01-01

    Over nearly 40 years, several scales have been developed to measure therapist theoretical orientation (Poznanski & McLennan, 1995). This study, unlike previous efforts, focuses on "community clinicians"--social workers and other mental health professionals (such as psychologists, counselors, psychiatrists, and psychiatric nurses) who work in…

  14. Conductivity study and fourier transform infrared (FTIR) characterization of methyl cellulose solid polymer electrolyte with sodium iodide conducting ion

    NASA Astrophysics Data System (ADS)

    Abiddin, Jamal Farghali Bin Zainal; Ahmad, Azizah Hanom

    2015-08-01

    Sodium ion (Na+) based solid polymer electrolyte (SPE) has been prepared using solution cast technique with distilled water as solvent and Methylcellulose (MC) as a polymer host. Methylcellulose polymer was chosen as the polymer host due to the abundance of lone pair electrons in the carbonyl and C-O-C constituents, which in turn provide multiple hopping sites for the Na+ conducting ions. Variable compositions of sodium iodide (NaI) salt were prepared to investigate the optimum MC-NaI weight ratio. Results from Electrical Impedance Spectroscopy (EIS) technique show that pure methylcellulose has a low conductivity of 3.61 × 10-11 S/cm.The conductivity increases as NaI content increases up to optimum NaIcomposition of 40 wt%, which yields an average conductivity of 2.70 × 10-5 S/cm.

  15. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: SOLVENT EXTRACTION 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 fact sheet focuses on solvent extraction treatability studies, and is highly abridged version of the guide which bears the...

  16. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: AEROBIC BIODEGRADATION REMEDY SCREENING

    EPA Science Inventory

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

  17. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: THERMAL DESORPTION - 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...

  18. Using a 3D Virtual Supermarket to Measure Food Purchase Behavior: A Validation Study

    PubMed Central

    Jiang, Yannan; Steenhuis, Ingrid Hendrika Margaretha; Ni Mhurchu, Cliona

    2015-01-01

    Background There is increasing recognition that supermarkets are an important environment for health-promoting interventions such as fiscal food policies or front-of-pack nutrition labeling. However, due to the complexities of undertaking such research in the real world, well-designed randomized controlled trials on these kinds of interventions are lacking. The Virtual Supermarket is a 3-dimensional computerized research environment designed to enable experimental studies in a supermarket setting without the complexity or costs normally associated with undertaking such research. Objective The primary objective was to validate the Virtual Supermarket by comparing virtual and real-life food purchasing behavior. A secondary objective was to obtain participant feedback on perceived sense of “presence” (the subjective experience of being in one place or environment even if physically located in another) in the Virtual Supermarket. Methods Eligible main household shoppers (New Zealand adults aged ≥18 years) were asked to conduct 3 shopping occasions in the Virtual Supermarket over 3 consecutive weeks, complete the validated Presence Questionnaire Items Stems, and collect their real supermarket grocery till receipts for that same period. Proportional expenditure (NZ$) and the proportion of products purchased over 18 major food groups were compared between the virtual and real supermarkets. Data were analyzed using repeated measures mixed models. Results A total of 123 participants consented to take part in the study. In total, 69.9% (86/123) completed 1 shop in the Virtual Supermarket, 64.2% (79/123) completed 2 shops, 60.2% (74/123) completed 3 shops, and 48.8% (60/123) returned their real supermarket till receipts. The 4 food groups with the highest relative expenditures were the same for the virtual and real supermarkets: fresh fruit and vegetables (virtual estimate: 14.3%; real: 17.4%), bread and bakery (virtual: 10.0%; real: 8.2%), dairy (virtual: 19.1%; real: 12.6%), and meat and fish (virtual: 16.5%; real: 16.8%). Significant differences in proportional expenditures were observed for 6 food groups, with largest differences (virtual – real) for dairy (in expenditure 6.5%, P<.001; in items 2.2%, P=.04) and fresh fruit and vegetables (in expenditure: –3.1%, P=.04; in items: 5.9%, P=.002). There was no trend of overspending in the Virtual Supermarket and participants experienced a medium-to-high presence (88%, 73/83 scored medium; 8%, 7/83 scored high). Conclusions Shopping patterns in the Virtual Supermarket were comparable to those in real life. Overall, the Virtual Supermarket is a valid tool to measure food purchasing behavior. Nevertheless, it is important to improve the functionality of some food categories, in particular fruit and vegetables and dairy. The results of this validation will assist in making further improvements to the software and with optimization of the internal and external validity of this innovative methodology. PMID:25921185

  19. A study of the collapse of spherical shells, Part II: Model Validation.

    SciTech Connect

    Thacker, B. H.; McKeighan, P. C.; Pepin, J. E.

    2005-01-01

    There is a growing need to quantify the level of credibility that can be associated with model predictions. Model verification and validation (V&V) is a methodology for the development of models that can be used to make engineering predictions with quantified confidence. Model V&V procedures are needed by government and industry to reduce the time, cost and risk associated with component and full-scale testing of products, materials, and weapons. Consequently, the development of guidelines and procedures for conducting a V&V program are currently being defined by a broad spectrum of researchers. This talk will discuss an on-going effort to validate a model that predicts the collapse load of a spherical shell structure. Inherent variations in geometric shape and material parameters are included in the uncertainty model. Results from a recently completed probabilistic validation test to measure the variation in collapse load are compared to the predicted collapse load variation.

  20. A Validation Study of the Korean-Ruminative Response Scale in Korean Adolescents

    PubMed Central

    Shin, Kyoung Min

    2015-01-01

    Objective We aimed to evaluate the psychometric properties of Korean version of Ruminative Response Scale (K-RRS) for Korean adolescents. Methods A community sample of 1220 adolescents was recruited from middle schools and high schools. Exploratory factor analyses and confirmatory factor analyses were conducted, and additional analyses were performed to assess the reliability and validity of the K-RRS. Results An exploratory factor analysis of a sample of adolescents (n=550) yielded a three factor structure: 'depressive rumination', 'reflective pondering', and 'brooding'. Confirmatory factor analyses of another sample of adolescents (n=530) supported the three-factor model for the K-RRS. The K-RRS was found to have good internal consistency and construct validity. Conclusion Our results suggest that K-RRS is a valid measurement to assess rumination in adolescents, as well as in adults. PMID:26508962

  1. Reliability and validity of the Center for Epidemiological Studies Depression Scale in 2 special adult samples from rural China.

    PubMed

    Zhang, Jie; Sun, Weiwei; Kong, Yuanyuan; Wang, Cuntong

    2012-11-01

    Few studies on the validation of the Center for Epidemiological Studies Depression Scale (CES-D) in Chinese have been conducted in the samples from rural area, whereas the mental health problems among rural Chinese deserve more attention. For instance, the suicide rate in rural China is about 3 times that of the urban rate. This study aimed at assessing reliability and validity of the CES-D in 2 special adult samples in rural China, with data obtained by face-to-face interviews. One sample consisted of the proxy informants for subjects who committed suicide, and the other was of the proxy informants for living controls. For each person who committed suicide and each control, a family member and close friend served as informants. This study focused on informants themselves (not the persons who committed suicide or the living control himself/herself). Suicide informants (n = 781) who had experienced the suicide of a relative or close friend in the past 6 months were compared with the control informants (n = 832) who had no such experience. Internal reliability was satisfactory (Cronbach coefficients were .949 for suicide informants and .880 for control informants). Good concurrent validity and criterion validity were found by analyzing the relations to negative life events and the Scale for Suicide Ideation. Confirmatory factor analyses indicated that 3-factor structure (positive affect, interpersonal problems, depressive mood and somatic symptoms combined) had good fit in rural Chinese. These findings suggested that the CES-D had good reliability and validity when applied in these 2 adult samples in rural China. Factor structure analyses of the CES-D indicated that "somatization" process of expressing depressive symptoms still existed among rural Chinese. PMID:22520090

  2. A Validation Study of Pin Heat Transfer for MOX Fuel Based on the IFA-597 Experiments

    SciTech Connect

    Phillippe, Aaron M; Clarno, Kevin T; Banfield, James E; Ott, Larry J; Philip, Bobby; Berrill, Mark A; Sampath, Rahul S; Allu, Srikanth; Hamilton, Steven P

    2014-01-01

    Abstract The IFA-597 (Integrated Fuel Assessment) experiments from the International Fuel Performance Experiments (IFPE) database were designed to study the thermal behavior of mixed oxide (MOX) fuel and the effects of an annulus on fission gas release in light-water-reactor fuel. An evaluation of nuclear fuel pin heat transfer in the FRAPCON-3.4 and Exnihilo codes for MOX fuel systems was performed, with a focus on the first 20 time steps ( 6 GWd/MT(iHM)) for explicit comparison between the codes. In addition, sensitivity studies were performed to evaluate the effect of the radial power shape and approximations to the geometry to account for the thermocouple hole, dish, and chamfer. The analysis demonstrated relative agreement for both solid (rod 1) and annular (rod 2) fuel in the experiment, demonstrating the accuracy of the codes and their underlying material models for MOX fuel, while also revealing a small energy loss artifact in how gap conductance is currently handled in Exnihilo for chamfered fuel pellets. The within-pellet power shape was shown to significantly impact the predicted centerline temperatures. This has provided an initial benchmarking of the pin heat transfer capability of Exnihilo for MOX fuel with respect to a well-validated nuclear fuel performance code.

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

    PubMed Central

    Greenwood, Charles R.; Hops, Hyman; Walker, Hill M.; Guild, Jacqueline J.; Stokes, Judith; Young, K. Richard; Keleman, Kenneth S.; Willardson, Marlyn

    1979-01-01

    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

  4. Conducting Real-Time Videofluoroscopic Swallow Study via Telepractice: A Preliminary Feasibility and Reliability Study.

    PubMed

    Burns, Clare L; Ward, Elizabeth C; Hill, Anne J; Phillips, Nick; Porter, Linda

    2016-06-01

    A small number of studies have examined the feasibility of conducting videofluoroscopic swallow studies (VFSS) via telepractice. While the results have confirmed this potential, the systems tested to date have either reported issues that impacted the ability to analyze/interpret the VFSS recordings in real time, or they were not designed to enable real-time interpretation. Further system design is needed to establish a telepractice model that enables the VFSS assessment to be both guided and interpreted live in real time. The aim of this study was to test the feasibility and reliability of using a telepractice system to enable live VFSS assessment. Twenty adult patients underwent a VFSS assessment directed by a telepractice SLP with competency in VFSS located in another room of the hospital. The telepractice clinician led the sessions using a C20 Cisco TelePresence System. This was linked in real time via a secure telehealth network (at 4 megabits per second (Mbit/s)) to a C60 Cisco TelePresence System located in a fluoroscopy suite, connected to the digital fluoroscopy system. Levels of agreement were calculated between the telepractice clinician and a face-to-face clinician who simultaneously rated the VFSS in real time. High levels of agreement for swallowing parameters (range = 75-100 %; k = -0.34 to 1.0) and management decisions (range = 70-100 %, k = 0.64-1.0) were found. A post-session questionnaire revealed clinicians agreed that the telepractice system enabled successful remote assessment of VFSS. The findings support the potential to conduct live VFSS assessment via a telepractice model. PMID:26979971

  5. The ECVAM International Validation Study on In Vitro Tests for Skin Corrosivity. 2. Results and Evaluation by the Management Team.

    PubMed

    Fentem, J H; Archer, G E; Balls, M; Botham, P A; Curren, R D; Earl, L K; Esdaile, D J; Holzhütter, H G; Liebsch, M

    1998-08-01

    As a follow-up to a prevalidation study on in vitro tests for replacing the in vivo rabbit test for skin corrosivity, an international validation study was conducted during 1996 and 1997 under the auspices of ECVAM. The main objectives of the study were to: (a) identify tests capable of discriminating corrosives from non-corrosives for selected types of chemicals and/or all chemicals; and (b) determine whether these tests could identify correctly known R35 (UN packing group I) and R34 (UN packing groups II & III) chemicals. The tests evaluated were the rat skin transcutaneous electrical resistance (TER) assay, CORROSITEX(TM), the Skin(2TM) ZK1350 corrosivity test and EPISKIN(TM). Each test was conducted in three independent laboratories. 60 coded chemicals were tested. All of the tests evaluated showed acceptable intralaboratory and interlaboratory reproducibilities, and the TER, Skin(2) and EPISKIN tests proved applicable to testing a diverse group of chemicals of different physical forms, including organic acids, organic bases, neutral organics, inorganic acids, inorganic bases, inorganic salts, electrophiles, phenols and soaps/surfactants. Two of the four tests evaluated, the TER assay and EPISKIN, met the criteria agreed by the Management Team concerning acceptable underprediction and overprediction rates for them to be considered scientifically validated for use as replacements for the animal test for distinguishing between corrosive and non-corrosive chemicals for all of the chemical types studied [objective (a)]. EPISKIN was the only test able to distinguish between known R35 (UN packing group I) and R34 (UN packing groups II & III) chemicals, for all of the chemical types included, on an acceptable number of occasions [objective (b)]. The corrosive potentials of about 40% of the test chemicals could not be assessed with CORROSITEX, and the assay did not meet all of the criteria for it to be considered acceptable as a replacement test. However, CORROSITEX may be valid for testing specific classes of chemicals, such as organic bases and inorganic acids. The Skin(2) assay did not meet the criteria for it to be considered scientifically validated. Thus, the validities of (i) the TER and EPISKIN assays for discriminating corrosives from non-corrosives, and (ii) the EPISKIN assay for identifying correctly known R35/I and R34/II & III chemicals, have been demonstrated in this study. CORROSITEX appears to be valid when used only with certain types of chemicals. PMID:20654431

  6. Validation of the Korean coefficient for the modification of diet in renal disease study equation

    PubMed Central

    Oh, Yun Jung; Cha, Ran-hui; Lee, Seung Hwan; Yu, Kyung Sang; Kim, Satbyul Estella; Kim, Ho; Kim, Yon Su

    2016-01-01

    Background/Aims: Race and ethnicity are important determinants when estimatingglomerular filtration rate (GFR). The Korean coefficients for the isotope dilution mass spectrometry (IDMS) Modification of Diet in Renal Disease (MDRD) Study equations were developed in 2010. However, the coefficients have not been validated. The aim of this study was to validate the performance of the Korean coefficients for the IDMS MDRD Study equations. Methods: Equation development and validation were performed in separate groups (development group, n = 147 from 2008 to 2009; validation group, n = 125 from 2010 to 2012). We compared the performance of the original IDMS MDRD equations and modified equations with Korean coefficients. Performance was assessed by comparing correlation coefficients, bias, and accuracy between estimated GFR and measured GFR, with systemic inulin clearance using a single injection method. Results: The Korean coefficients for the IDMS MDRD equations developed previously showed good performance in the validation group. The new Korean coefficients for the four- and six-variable IDMS MDRD equations using both the development and validation cohorts were 1.02046 and 0.97300, respectively. No significant difference was detected for the new Korean coefficients, in terms of estimating GFR, between the original and modified IDMS MDRD Study equations. Conclusions: The modified equations with Korean coefficients for the IDMS MDRD Study equations were not superior to the original equations for estimating GFR. Therefore, we recommend using the original IDMS MDRD Study equation without ethnic adjustment in the Korean population. PMID:26759158

  7. Note: Optimization of the numerical data analysis for conductivity percolation studies of drying moist porous systems

    SciTech Connect

    Moscicki, J. K.; Sokolowska, D.; Dziob, D.; Nowak, J.; Kwiatkowski, L.

    2014-02-15

    A simplified data analysis protocol, for dielectric spectroscopy use to study conductivity percolation in dehydrating granular media is discussed. To enhance visibility of the protonic conductivity contribution to the dielectric loss spectrum, detrimental effects of either low-frequency dielectric relaxation or electrode polarization are removed. Use of the directly measurable monofrequency dielectric loss factor rather than estimated DC conductivity to parameterize the percolation transition substantially reduces the analysis work and time.

  8. Note: Optimization of the numerical data analysis for conductivity percolation studies of drying moist porous systems

    NASA Astrophysics Data System (ADS)

    Moscicki, J. K.; Sokolowska, D.; Kwiatkowski, L.; Dziob, D.; Nowak, J.

    2014-02-01

    A simplified data analysis protocol, for dielectric spectroscopy use to study conductivity percolation in dehydrating granular media is discussed. To enhance visibility of the protonic conductivity contribution to the dielectric loss spectrum, detrimental effects of either low-frequency dielectric relaxation or electrode polarization are removed. Use of the directly measurable monofrequency dielectric loss factor rather than estimated DC conductivity to parameterize the percolation transition substantially reduces the analysis work and time.

  9. Effect of nifedipine on atrioventricular conduction as compared with verapamil. Intracardiac electrophysiological study.

    PubMed Central

    Rowland, E; Evans, T; Krikler, D

    1979-01-01

    Intravenous nifedipine, a powerful calcium antagonist, had no obvious effect on atrioventricular conduction when administered to 11 patients during routine intracardiac electrophysiological studies. Verapamil on the other hand showed potent antiarrhythmic properties, depressing atrioventricular nodal conduction. Nifedipine thus appears safe in patients with angina pectoris who have disorders of atrioventricular nodal conduction, and in those receiving beta-adrenergic blocking drugs. There appear to be differential effects on the slow inward channels of cardiac cells with different 'calcium antagonists'. PMID:486272

  10. Clinical examination of varicose veins--a validation study.

    PubMed Central

    Kim, J.; Richards, S.; Kent, P. J.

    2000-01-01

    The aim of this study was to determine the accuracy of clinical tests compared to colour duplex imaging in patients with primary varicose veins using a prospective, blinded comparison study. A total of 44 patients (70 limbs) with primary, previously untreated varicose veins presenting to the vascular laboratory of a university teaching hospital were studied. The patients underwent physical examination using the cough test, the tap test, Trendelenbergs' test, Perthes' test and hand-held Doppler (HHD) assessment prior to undergoing colour duplex scanning. Reflux was detected on duplex scanning, at the sapheno-femoral junction in 39/70 limbs (54%), the long saphenous vein in 47/70 limbs (64%) and the sapheno-popliteal junction in 9/70 limbs (13%). The cough test had low sensitivity (0.59) and specificity (0.67). The tap test had low sensitivity (0.18) and high specificity (0.92). The Trendelenberg test had high sensitivity (0.91) but low specificity (0.15). Perthes' test had a high sensitivity (0.97) but low specificity (0.20). Hand-held Doppler assessment of reflux at the sapheno-femoral junction, in the long saphenous vein and at the sapheno-popliteal junction had high sensitivity (0.97, 0.82, and 0.80, respectively) and specificity (0.73, 0.92, and 0.90, respectively) of detecting reflux. Clinical tests used in the examination of patients with primary varicose veins are inaccurate. Assessment using hand-held Doppler is more accurate. Courses and clinical textbooks should be revised to replace these tests with instruction in how to use hand-held Doppler in the clinical examination of patients with varicose veins. PMID:10858678

  11. Validation of protein carbonyl measurement: A multi-centre study

    PubMed Central

    Augustyniak, Edyta; Adam, Aisha; Wojdyla, Katarzyna; Rogowska-Wrzesinska, Adelina; Willetts, Rachel; Korkmaz, Ayhan; Atalay, Mustafa; Weber, Daniela; Grune, Tilman; Borsa, Claudia; Gradinaru, Daniela; Chand Bollineni, Ravi; Fedorova, Maria; Griffiths, Helen R.

    2014-01-01

    Protein carbonyls are widely analysed as a measure of protein oxidation. Several different methods exist for their determination. A previous study had described orders of magnitude variance that existed when protein carbonyls were analysed in a single laboratory by ELISA using different commercial kits. We have further explored the potential causes of variance in carbonyl analysis in a ring study. A soluble protein fraction was prepared from rat liver and exposed to 0, 5 and 15 min of UV irradiation. Lyophilised preparations were distributed to six different laboratories that routinely undertook protein carbonyl analysis across Europe. ELISA and Western blotting techniques detected an increase in protein carbonyl formation between 0 and 5 min of UV irradiation irrespective of method used. After irradiation for 15 min, less oxidation was detected by half of the laboratories than after 5 min irradiation. Three of the four ELISA carbonyl results fell within 95% confidence intervals. Likely errors in calculating absolute carbonyl values may be attributed to differences in standardisation. Out of up to 88 proteins identified as containing carbonyl groups after tryptic cleavage of irradiated and control liver proteins, only seven were common in all three liver preparations. Lysine and arginine residues modified by carbonyls are likely to be resistant to tryptic proteolysis. Use of a cocktail of proteases may increase the recovery of oxidised peptides. In conclusion, standardisation is critical for carbonyl analysis and heavily oxidised proteins may not be effectively analysed by any existing technique. PMID:25560243

  12. In-Trail Procedure Air Traffic Control Procedures Validation Simulation Study

    NASA Technical Reports Server (NTRS)

    Chartrand, Ryan C.; Hewitt, Katrin P.; Sweeney, Peter B.; Graff, Thomas J.; Jones, Kenneth M.

    2012-01-01

    In August 2007, Airservices Australia (Airservices) and the United States National Aeronautics and Space Administration (NASA) conducted a validation experiment of the air traffic control (ATC) procedures associated with the Automatic Dependant Surveillance-Broadcast (ADS-B) In-Trail Procedure (ITP). ITP is an Airborne Traffic Situation Awareness (ATSA) application designed for near-term use in procedural airspace in which ADS-B data are used to facilitate climb and descent maneuvers. NASA and Airservices conducted the experiment in Airservices simulator in Melbourne, Australia. Twelve current operational air traffic controllers participated in the experiment, which identified aspects of the ITP that could be improved (mainly in the communication and controller approval process). Results showed that controllers viewed the ITP as valid and acceptable. This paper describes the experiment design and results.

  13. Intelligent Emergency Department: Validation of Sociometers to Study Workload.

    PubMed

    Yu, Denny; Blocker, Renaldo C; Sir, Mustafa Y; Hallbeck, M Susan; Hellmich, Thomas R; Cohen, Tara; Nestler, David M; Pasupathy, Kalyan S

    2016-03-01

    Sociometers are wearable sensors that continuously measure body movements, interactions, and speech. The purpose of this study is to test sociometers in a smart environment in a live clinical setting, to assess their reliability in capturing and quantifying data. The long-term goal of this work is to create an intelligent emergency department that captures real-time human interactions using sociometers to sense current system dynamics, predict future state, and continuously learn to enable the highest levels of emergency care delivery. Ten actors wore the devices during five simulated scenarios in the emergency care wards at a large non-profit medical institution. For each scenario, actors recited prewritten or structured dialogue while independent variables, e.g., distance, angle, obstructions, speech behavior, were independently controlled. Data streams from the sociometers were compared to gold standard video and audio data captured by two ward and hallway cameras. Sociometers distinguished body movement differences in mean angular velocity between individuals sitting, standing, walking intermittently, and walking continuously. Face-to-face (F2F) interactions were not detected when individuals were offset by 30°, 60°, and 180° angles. Under ideal F2F conditions, interactions were detected 50 % of the time (4/8 actor pairs). Proximity between individuals was detected for 13/15 actor pairs. Devices underestimated the mean duration of speech by 30-44 s, but were effective at distinguishing the dominant speaker. The results inform engineers to refine sociometers and provide health system researchers a tool for quantifying the dynamics and behaviors in complex and unpredictable healthcare environments such as emergency care. PMID:26645317

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

    SciTech Connect

    Levko, D.; Gurovich, V. Tz.; Krasik, Ya. E.

    2012-06-15

    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.

  15. Conduction in polyaniline emeraldine salt in the terahertz region: A temperature dependence study

    NASA Astrophysics Data System (ADS)

    Tapia, Alvin Karlo G.; Tominaga, Keisuke

    2014-04-01

    The temperature-dependent conductivity of polyaniline emeraldine salt (PAni-ES) was studied by terahertz (THz) time-domain spectroscopy from 80 to 290 K to investigate conduction properties in the THz region. The absorption coefficient and index of refraction increase with temperature. This reflects an increasing conductivity, which indicates a thermally assisted hopping transition. The frequency-dependent behavior of the conductivity is described by using the Mott-Davis model. The model fitting parameter, S, decreases with increasing temperature, indicating a possible correlated barrier hopping mechanism. Lastly, the activation energy at THz frequencies decreases with increasing frequency, suggesting intraband transitions.

  16. Validity and Reliability Study of the Self-Efficacy Scale in Rendering Piano Education to Children of 6-12 Years

    ERIC Educational Resources Information Center

    Ekinci, Hatice

    2014-01-01

    This study was conducted in order to develop a valid and reliable scale that can be used in measuring self-efficacy of candidate music teachers in rendering piano education to children of 6-12 years. To this end, a pool of 51 items was created by using the literature, and taking the opinions of piano professors and piano instructors working with

  17. Validity and Reliability Study of the Self-Efficacy Scale in Rendering Piano Education to Children of 6-12 Years

    ERIC Educational Resources Information Center

    Ekinci, Hatice

    2014-01-01

    This study was conducted in order to develop a valid and reliable scale that can be used in measuring self-efficacy of candidate music teachers in rendering piano education to children of 6-12 years. To this end, a pool of 51 items was created by using the literature, and taking the opinions of piano professors and piano instructors working with…

  18. Validity Study of U.T. Austin Test for Use in Credit by Examination in Introduction to Electronic Data Processing (DPA 310), Fall 1987.

    ERIC Educational Resources Information Center

    Appenzellar, Anne B.; Kelley, H. Paul

    The Measurement and Evaluation Center of the University of Texas (Austin) conducted a validity study to assist the Department of Management Science and Information (DMSI) at the College of Business Administration in establishing a program of credit by examination for an introductory course in electronic data processing--Data Processing Analysis…

  19. Validity Study of the College Board Achievement Test in Russian Listening-Reading at U.T. Austin during the Academic Year 1986-1987.

    ERIC Educational Resources Information Center

    Appenzellar, Anne B.; Kelley, H. Paul

    The University of Texas at Austin conducted a validity study of the College Board Achievement Test in Russian Listening-Reading during the 1986-87 academic year. The test, a multiple-choice test with audio-taped and reading portions, was administered to 298 students in 22 sections of 8 courses in Russian. The purpose was to revalidate the test as…

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

    ERIC Educational Resources Information Center

    Crance Gutmann, Gina-Lyn

    2008-01-01

    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…

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

    ERIC Educational Resources Information Center

    Romano, Jeanine; Kromrey, Jeffrey D.

    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…

  2. "Conducting Is Everywhere!" A Case Study of the Development of Preservice Music Teacher Occupational Identity in a Beginning Conducting Course

    ERIC Educational Resources Information Center

    Johnson, Erik

    2014-01-01

    Research on pre-service music teacher occupational identity often highlights two competing identities: performer and teacher (L'Roy, 1983; Roberts, 1991; Pellegrino, 2009). Of the many factors that contribute to the occupational identity of the pre-service music teacher (Woodford, 2002), conducting has the potential to integrate performer and…

  3. Infrared spectroscopic and conductivity studies of ureasil-based proton conducting membranes for medium temperature fuel cell applications.

    PubMed

    Vince, Jelica; Vuk, Angela urca; Stangar, Urka Lavren?i?; Pere, Lidija Slemenik; Orel, Boris; Ho?evar, Stanko

    2010-12-01

    Proton conducting membranes for fuel cells were prepared by the sol-gel process from two different ureasil organic-inorganic hybrid precursors: bis[(N-(3-triethoxysilylpropyl)ureido]-terminated poly(propylene glycol) 4000 (PPGU) and bis[3-(N-(3-triethoxysilylpropyl)ureido)propyl]-terminated poly(dimethylsiloxane) 1000 (PDMSU). Heteropoly silicotungstic acid was added to actuate the reactions of hydrolysis and condensation and to introduce proton conductivity. XRD measurements of membranes revealed the presence of a diffraction peak at 6.3, which could be ascribed to gradual formation of R-(SiO3/2) silsesquioxane clusters, i.e. arrangement of the Si-O-Si skeleton on the nano-scale. TG and DSC measurements showed thermal stability of the membranes above 120 C. Proton conductivities at room temperature were of the order of 10-4 to 10-3 S/cm, classifying the membranes in the group of super ionic conductors. At elevated temperatures up to 160 C and at conditions of autogenous pressure, conductivities increased up to values acceptable for fuel cells of 10-1 S/cm, which could be the result of the presence of H3O+ ions. The protonation of the urea groups and the formation of amidonium ions [C(OH)=NH+] were followed using IR ATR spectroscopy. PMID:24061888

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

    PubMed

    DeVoe, D; Dalleck, L

    2001-08-01

    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

  5. Conductive olfactory losses in chronic rhinosinusitis? – A computational fluid dynamics study of 29 patients

    PubMed Central

    Zhao, Kai; Jiang, Jianbo; Pribitkin, Edmund A.; Dalton, Pamela; Rosen, David; Lyman, Brian; Yee, Karen K.; Rawson, Nancy E.; Cowart, Beverly J.

    2014-01-01

    Objective Besides sensorineural factors, conductive impediments likely contribute to olfactory losses in chronic rhinosinusitis (CRS) patients, yet no conclusive evidence exists. We aimed to examine possible conductive factors using computational fluid dynamics (CFD) models. Methods 29 CRS patients were assessed via odorant detection thresholds (ODTs), rhinomanometry (nasal resistance: NR), acoustic rhinometry (minimum-cross-sectional area: MCA) and CT staging. CFD simulations of nasal airflow and odorant absorption to olfactory region were carried out based on individual CTs. Biopsies of olfactory epithelium (OE) were collected, cryo-sectioned, stained and scored for erosion. Results Significant correlations to ODTs were found for three variables: odor absorption in the olfactory region (r=−0.60, p<0.01), MCA (r=−0.40, p<0.05) and CT staging (r=0.42, p<0.05). However, significant findings were limited to ODTs of the highly soluble l-carvone. Multiple regression analysis revealed that these variables combined, with the addition of NR, can account for 65% of the total variance in ODTs. CT staging correlated significantly with OE erosion (r=0.77, p<0.01) and can replace the latter in the regression with comparable outcomes. Partial correlations suggest the contributions of both conductive and sensorineural variables are more prominent if adjusted for the effects of the other. Olfactory loss and inflammatory factors have strong bilateral involvement, while conductive factors are independent between sides. As validation, CFD-simulated NRs significantly correlated with rhinomanometrically assessed ones (r=0.60, p<0.01). Conclusion Both conductive and sensorineural mechanisms can contribute to olfactory losses in CRS. CFD modeling provides critical guidance in understanding the role of conductive impediments in olfactory dysfunction in CRS. PMID:24449655

  6. Latino Community-Based Participatory Research Studies: A Model for Conducting Bilingual Translations

    PubMed Central

    Sánchez-Johnsen, Lisa; Escamilla, Julia; Rodriguez, Erin M.; Vega, Susan; Bolaños, Liliana

    2015-01-01

    Many behavioral health materials have not been translated into Spanish. Of those that are available in Spanish, some of them have not been translated correctly, many are only appropriate for a subgroup of Latinos, and/or multiple versions of the same materials exist. This article describes an innovative model of conducting bilingual English–Spanish translations as part of community-based participatory research studies and provides recommendations based on this model. In this article, the traditional process of conducting bilingual translations is reviewed, and an innovative model for conducting translations in collaboration with community partners is described. Finally, recommendations for conducting future health research studies with community partners are provided. Researchers, health care providers, educators, and community partners will benefit from learning about this innovative model that helps produce materials that are more culturally appropriate than those that are produced with the most commonly used method of conducting translations. PMID:25741929

  7. Crystalline polymers with exceptionally low thermal conductivity studied using molecular dynamics

    NASA Astrophysics Data System (ADS)

    Robbins, Andrew B.; Minnich, Austin J.

    2015-11-01

    Semi-crystalline polymers have been shown to have greatly increased thermal conductivity compared to amorphous bulk polymers due to effective heat conduction along the covalent bonds of the backbone. However, the mechanisms governing the intrinsic thermal conductivity of polymers remain largely unexplored as thermal transport has been studied in relatively few polymers. Here, we use molecular dynamics simulations to study heat transport in polynorbornene, a polymer that can be synthesized in semi-crystalline form using solution processing. We find that even perfectly crystalline polynorbornene has an exceptionally low thermal conductivity near the amorphous limit due to extremely strong anharmonic scattering. Our calculations show that this scattering is sufficiently strong to prevent the formation of propagating phonons, with heat being instead carried by non-propagating, delocalized vibrational modes known as diffusons. Our results demonstrate a mechanism for achieving intrinsically low thermal conductivity even in crystalline polymers that may be useful for organic thermoelectrics.

  8. Electrical conductivity studies on CuBr containing Al2O3 particles

    NASA Technical Reports Server (NTRS)

    Dubec, P. M.; Wagner, J. B., Jr.

    1984-01-01

    The conductivity of CuBr was studied and the role of a second phase, Al2O3, dispersed in CuBr was tested. CuBr melts at 493 C and exhibits three phases in the solid state. CuBr is a good ionic conductor with a transport number for copper ions of virtually unity with weighed proportions of the appropriate chemicals used. The CuBr materials were heated above melting point of CuBr, and the samples were sandwiched between copper electrodes. The ac conductivity, was determined at 1 kHz between 25 and 440 C depending on the sample. It was shown that at low temperatures, the conductivity for CuBr (Al2O3) increased by as much as 100, whereas in the beta phase the conductivity of CuBr containing Al2O3 decreased. The electrical conductivity studies are in agreement with earlier data.

  9. Improving DNA data exchange: validation studies on a single 6 dye STR kit with 24 loci.

    PubMed

    Martín, Pablo; de Simón, Lourdes Fernández; Luque, Gracia; Farfán, María José; Alonso, Antonio

    2014-11-01

    The idea of developing a new multiplex STR amplification system was conceived in 2011 as an effective way to implement the new European standard set (ESS) of 12 STR markers adopted by The Council of the European Union in 2009 while maintaining an effective compatibility and information exchange with the historical DNA profiles contained in the Spanish national DNA database (around 200,000 DNA profiles) mainly based on the 13 CODIS core STR loci plus D19S433 and D2S1338 markers. With this goal in mind we proposed to test and validate a single STR amplification system for simultaneous analysis of 21 STR markers covering both CODIS and ESS core STR loci plus three additional markers (D19S433, D2S1338, and SE33) also contained in commonly used STR kits and national DNA databases. In 2012, we started the first beta-testing with a 6-dye STR kit prototype containing 24 loci (now known as the GlobalFiler™ PCR Amplification Kit) developed by Life Technologies in response to the CODIS Core Loci Working Group's recommendation to expand the CODIS Core Loci. This prototype included our proposal of 21 autosomal STR markers and two Y-chromosome markers (DYS391 and Y-indel) and maximizes concordance with established databases and previously analyzed samples by maintaining primer sequences of previous Identifiler(®)/NGM SElect™ kits for the 21 STR markers except for TPOX. This paper describes the validation studies conducted with the first commercial available 6-dye STR kit for casework using a 3500 genetic analyzer for fragment detection that included the analysis of the following parameters and aspects: analytical threshold, sensitivity & stochastic threshold, heterozygous balance, stutter threshold, precision and accuracy, repeatability and reproducibility, genotype concordance, DNA mixtures, species specificity, and stability studies with case type samples. The studies demonstrated that the GlobalFiler™ system provided equivalent overall performance to previous forensic STR PCR kits, but with enhanced discrimination power for a better match efficiency that would reduce the chance of adventitious matches during DNA data exchange among national DNA databases. PMID:25082138

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

    PubMed

    Morris, Jerry

    2013-09-01

    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

  11. Preliminary study on improvement of cementitious grout thermal conductivity for geothermal heat pump applications

    SciTech Connect

    Allan, M.L.

    1996-06-01

    Preliminary studies were preformed to determine whether thermal conductivity of cementitious grouts used to backfill heat exchanger loops for geothermal heat pumps could be improved, thus improving efficiency. Grouts containing selected additives were compares with conventional bentonite and cement grouts. Significant enhancement of grout alumina grit, steel fibers, and silicon carbide increased the thermal conductivity when compared to unfilled, high solids bentonite grouts and conventional cement grouts. Furthermore, the developed grouts retained high thermal conductivity in the dry state, where as conventional bentonite and cement grouts tend to act as insulators if moisture is lost. The cementitious grouts studied can be mixed and placed using conventional grouting equipment.

  12. Study of Electrical Conductivity and Dielectric Behaviour of Molybdenum containing Bismuth Borate Glasses

    NASA Astrophysics Data System (ADS)

    Kishore, N.; Sanjay; Agarwal, A.; Dahiya, Sanjay; Pal, Inder

    2015-02-01

    Bismuth borate glasses containing MoO3 content have been synthesized by the standard melt-quenching technique. The samples have been characterized by X-ray diffraction and scanning electron microscopy. Frequency and temperature dependent conductivity measurements have been carried out in the range of 20Hz to 1MHz and in the temperature range of 373K to 623K respectively. The frequency dependent conductivity has been studied using both conductivity and modulus formalisms. The dielectric permittivity (ε' and ε"), electrical modulus (M*) and dielectric loss were also studied of the prepared glasses. The values of ε' and ε'' are found to decrease with increase in frequency.

  13. Thermal design studies in superconducting rf cavities: Phonon peak and Kapitza conductance

    NASA Astrophysics Data System (ADS)

    Aizaz, A.; Grimm, T. L.; Wright, N. T.

    2010-09-01

    Thermal design studies of superconducting radio frequency (SRF) cavities involve two thermal parameters, namely the temperature dependent thermal conductivity of Nb at low temperatures and the heat transfer coefficient at the Nb-He II interface, commonly known as the Kapitza conductance. During the fabrication process of the SRF cavities, Nb sheet is plastically deformed through a deep drawing process to obtain the desired shape. The effect of plastic deformation on low temperature thermal conductivity as well as Kapitza conductance has been studied experimentally. Strain induced during the plastic deformation process reduces the thermal conductivity in its phonon transmission regime (disappearance of phonon peak) by 80%, which may explain the performance limitations of the defect-free SRF cavities during their high field operations. Low temperature annealing of the deformed Nb sample could not recover the phonon peak. However, moderate temperature annealing during the titanification process recovered the phonon peak in the thermal conductivity curve. Kapitza conductance measurements for the Nb-He II interface for various surface topologies have also been carried out before and after the annealing. These measurements reveal consistently increased Kapitza conductance after the annealing process was carried out in the two temperature regimes.

  14. Curriculum Design Orientations Preference Scale of Teachers: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Bas, Gokhan

    2013-01-01

    The purpose of this study was to develop a valid and reliable scale for preferences of teachers in regard of their curriculum design orientations. Because there was no scale development study similar to this one in Turkey, it was considered as an urgent need to develop such a scale in the study. The sample of the research consisted of 300…

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

    NASA Astrophysics Data System (ADS)

    Sawtelle, Vashti; Brewe, Eric; Kramer, Laird

    2009-12-01

    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.

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

    PubMed Central

    2012-01-01

    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. PMID:23072651

  17. VALUE - A Framework to Validate Downscaling Approaches for Climate Change Studies

    NASA Astrophysics Data System (ADS)

    Maraun, Douglas; Widmann, Martin; Gutiérrez, José M.; Kotlarski, Sven; Chandler, Richard E.; Hertig, Elke; Wibig, Joanna; Huth, Radan; Wilke, Renate A. I.

    2015-04-01

    VALUE is an open European network to validate and compare downscaling methods for climate change research. VALUE aims to foster collaboration and knowledge exchange between climatologists, impact modellers, statisticians, and stakeholders to establish an interdisciplinary downscaling community. A key deliverable of VALUE is the development of a systematic validation framework to enable the assessment and comparison of both dynamical and statistical downscaling methods. Here, we present the key ingredients of this framework. VALUE's main approach to validation is user-focused: starting from a specific user problem, a validation tree guides the selection of relevant validation indices and performance measures. Several experiments have been designed to isolate specific points in the downscaling procedure where problems may occur: what is the isolated downscaling skill? How do statistical and dynamical methods compare? How do methods perform at different spatial scales? Do methods fail in representing regional climate change? How is the overall representation of regional climate, including errors inherited from global climate models? The framework will be the basis for a comprehensive community-open downscaling intercomparison study, but is intended also to provide general guidance for other validation studies.

  18. VALUE: A framework to validate downscaling approaches for climate change studies

    NASA Astrophysics Data System (ADS)

    Maraun, Douglas; Widmann, Martin; Gutiérrez, José M.; Kotlarski, Sven; Chandler, Richard E.; Hertig, Elke; Wibig, Joanna; Huth, Radan; Wilcke, Renate A. I.

    2015-01-01

    VALUE is an open European network to validate and compare downscaling methods for climate change research. VALUE aims to foster collaboration and knowledge exchange between climatologists, impact modellers, statisticians, and stakeholders to establish an interdisciplinary downscaling community. A key deliverable of VALUE is the development of a systematic validation framework to enable the assessment and comparison of both dynamical and statistical downscaling methods. In this paper, we present the key ingredients of this framework. VALUE's main approach to validation is user- focused: starting from a specific user problem, a validation tree guides the selection of relevant validation indices and performance measures. Several experiments have been designed to isolate specific points in the downscaling procedure where problems may occur: what is the isolated downscaling skill? How do statistical and dynamical methods compare? How do methods perform at different spatial scales? Do methods fail in representing regional climate change? How is the overall representation of regional climate, including errors inherited from global climate models? The framework will be the basis for a comprehensive community-open downscaling intercomparison study, but is intended also to provide general guidance for other validation studies.

  19. Evaluation of Nerve Conduction Studies in Obese Children With Insulin Resistance or Impaired Glucose Tolerance.

    PubMed

    Ince, Hülya; Taşdemir, Haydar Ali; Aydin, Murat; Ozyürek, Hamit; Tilki, Hacer Erdem

    2015-07-01

    The aim of the study was to investigate nerve conduction studies in terms of neuropathic characteristics in obese patients who were in prediabetes stage and also to determine the abnormal findings. The study included 69 obese adolescent patients between April 2009 and December 2010. All patients and control group underwent motor (median, ulnar, tibial, and peroneal) and sensory (median, ulnar, sural, and medial plantar) nerve conduction studies and sympathetic skin response test. Sensory response amplitude of the medial plantar nerve was significantly lower in the patients with impaired glucose tolerance and insulin resistance. To our knowledge, the present study is the first study demonstrating the development of sensory and autonomic neuropathy due to metabolic complications of obesity in adolescent children even in the period without development of diabetes mellitus. We recommend that routine electrophysiological examinations be performed, using medial plantar nerve conduction studies and sympathetic skin response test. PMID:25342307

  20. Conducting feasibilities in clinical trials: an investment to ensure a good study.

    PubMed

    Rajadhyaksha, Viraj

    2010-07-01

    Conducting clinical trial feasibility is one of the first steps in clinical trial conduct. This process includes assessing internal and environmental capacity, alignment of the clinical trial in terms of study design, dose of investigational product, comparator, patient type, with the local environment and assessing potential of conducting clinical trial in a specific country. A robust feasibility also ensures a realistic assessment and capability to conduct the clinical trial. For local affiliates of pharmaceutical organizations, and contract research organizations, this is a precursor to study placement and influences the decision of study placement. This article provides details on different types of feasibilities, information which is to be included and relevance of each. The article also aims to provide practical hands-on suggestions to make feasibilities more realistic and informative. PMID:21814631

  1. Communication: minimum in the thermal conductivity of supercooled water: a computer simulation study.

    PubMed

    Bresme, F; Biddle, J W; Sengers, J V; Anisimov, M A

    2014-04-28

    We report the results of a computer simulation study of the thermodynamic properties and the thermal conductivity of supercooled water as a function of pressure and temperature using the TIP4P-2005 water model. The thermodynamic properties can be represented by a two-structure equation of state consistent with the presence of a liquid-liquid critical point in the supercooled region. Our simulations confirm the presence of a minimum in the thermal conductivity, not only at atmospheric pressure, as previously found for the TIP5P water model, but also at elevated pressures. This anomalous behavior of the thermal conductivity of supercooled water appears to be related to the maximum of the isothermal compressibility or the minimum of the speed of sound. However, the magnitudes of the simulated thermal conductivities are sensitive to the water model adopted and appear to be significantly larger than the experimental thermal conductivities of real water at low temperatures. PMID:24784243

  2. Communication: Minimum in the thermal conductivity of supercooled water: A computer simulation study

    SciTech Connect

    Bresme, F.; Biddle, J. W.; Sengers, J. V.; Anisimov, M. A.

    2014-04-28

    We report the results of a computer simulation study of the thermodynamic properties and the thermal conductivity of supercooled water as a function of pressure and temperature using the TIP4P-2005 water model. The thermodynamic properties can be represented by a two-structure equation of state consistent with the presence of a liquid-liquid critical point in the supercooled region. Our simulations confirm the presence of a minimum in the thermal conductivity, not only at atmospheric pressure, as previously found for the TIP5P water model, but also at elevated pressures. This anomalous behavior of the thermal conductivity of supercooled water appears to be related to the maximum of the isothermal compressibility or the minimum of the speed of sound. However, the magnitudes of the simulated thermal conductivities are sensitive to the water model adopted and appear to be significantly larger than the experimental thermal conductivities of real water at low temperatures.

  3. First-principles study of lattice thermal conductivity of Td-WTe2

    NASA Astrophysics Data System (ADS)

    Liu, Gang; Sun, Hong Yi; Zhou, Jian; Li, Qing Fang; Wan, Xian-Gang

    2016-03-01

    The structural and thermal properties of bulk Td-WTe2 have been studied by using first-principles calculations based on the simple Klemens model and an iterative self-consistent method. Both methods show that lattice thermal conductivity is anisotropic, with the highest value in the (001) plane, and lowest one along the c-axis at 300 K. The calculated average thermal conductivity of WTe2 is in agreement with the experimental measurement. The size dependent thermal conductivity shows that nanostructuring of WTe2 can possibly further decrease the lattice thermal conductivity, which can improve the thermoelectric efficiency. Such extremely low thermal conductivity, even much lower than WSe2, makes WTe2 having many potential applications in thermal insulation and thermoelectric materials.

  4. Measurement of craniovertebral angle by the Modified Head Posture Spinal Curvature Instrument: A reliability and validity study.

    PubMed

    Subbarayalu, Arun Vijay

    2016-02-01

    The Modified Head Posture Spinal Curvature Instrument (MHPSCI) is an extension of the Head Posture Spinal Curvature Instrument. Two specific modifications were made in the original design by adding a third arm projecting horizontally from the protractor to objectively fix the pivot exactly over the C7 vertebra and the addition of a spirit-level to properly align the instrument. In order to demonstrate reliability and validity, this study was conducted using patients with postural neck pain (N = 65) and healthy subjects (N = 20). All the subjects were working at a selected Information Technology Industry in India and had been recruited using a criterion-based sampling approach. The craniovertebral (CV) angle of each subject was evaluated by two raters consecutively. The measurements were taken by using both MHPSCI and the standard photographic method in a standardized sitting posture for the purpose of establishing criterion-validity of the instrument. The results of this study indicate a good inter-rater reliability (ICC = 0.76; CI = 0.65-0.84) as well as intra-rater reliability (ICC = 0.87; CI = 0.82-0.91) between three successive CV angle measurements (with 2 minutes interval between each measurement) through MHPSCI. While keeping the digital photographic measurement as a standard, this study established that the MHPSCI is a valid tool for measuring the CV angle as shown by non-significant difference (p > 0.01) and high correlation between the two methods (r = 0.79-0.84). This study demonstrates that the MHPSCI is a reliable and valid instrument for measuring CV angle in subjects with or without postural neck pain. PMID:26756923

  5. Photoconductivity, low-temperature conductivity, and magnetoresistance studies on the layered semiconductor GaTe

    SciTech Connect

    Bose, D. N.; Pal, Sarbari

    2001-06-15

    Single crystals of p-GaTe were grown by the Bridgman technique and characterized through x-ray diffraction, energy-dispersive x-ray analysis, x-ray photoemission spectroscopy, and transmission electron microscopy studies. The photoconductivity spectral response for in-plane conduction showed a peak at 747 nm (1.66 eV). Photoconductivity gain was determined in two orthogonal directions from which the majority carrier (hole) lifetimes were found to be 3.43{times}10{sup {minus}7} and 2.03{times}10{sup {minus}6}s, respectively, parallel and perpendicular to the layer planes. Studies of the temperature dependence of conductivity in the directions along and perpendicular to the layer planes were carried out between 10 and 80 K. Along the layer planes the conductance G{sub {parallel}} varied as lnT between 12 and 20 K, characteristic of weak localization, while between 20 and 50 K the conductivity {sigma}{sub {parallel}} varied as T{sup 1/2}. In the perpendicular direction the conductance G{sub {perpendicular}} varied as exp(T/T{sub 0}){sup 1/3} between 9 and 20 K and the conductivity {sigma}{sub {perpendicular}} varied as exp(T/T{sub 0}){sup 1/4} between 20 and 50 K, characteristic of hopping conduction in two and three dimensions, respectively. Negative transverse magnetoresistance was observed at 10 K for conduction in both directions for magnetic fields H{lt}0.4T, the increase in conductance being found to be proportional to H{sup 2}. Band conduction with positive magnetoresistance was observed for both current directions at T{gt}70K. The I-V characteristics at 10 K showed quantized behavior due to electron tunneling across potential barriers caused by stacking faults between layer planes.

  6. Validation of the automatic image analyser to assess retinal vessel calibre (ALTAIR): a prospective study protocol

    PubMed Central

    Garcia-Ortiz, Luis; Gómez-Marcos, Manuel A; Recio-Rodríguez, Jose I; Maderuelo-Fernández, Jose A; Chamoso-Santos, Pablo; Rodríguez-González, Sara; de Paz-Santana, Juan F; Merchan-Cifuentes, Miguel A; Corchado-Rodríguez, Juan M

    2014-01-01

    Introduction The fundus examination is a non-invasive evaluation of the microcirculation of the retina. The aim of the present study is to develop and validate (reliability and validity) the ALTAIR software platform (Automatic image analyser to assess retinal vessel calibre) in order to analyse its utility in different clinical environments. Methods and analysis A cross-sectional study in the first phase and a prospective observational study in the second with 4 years of follow-up. The study will be performed in a primary care centre and will include 386 participants. The main measurements will include carotid intima-media thickness, pulse wave velocity by Sphygmocor, cardio-ankle vascular index through the VASERA VS-1500, cardiac evaluation by a digital ECG and renal injury by microalbuminuria and glomerular filtration. The retinal vascular evaluation will be performed using a TOPCON TRCNW200 non-mydriatic retinal camera to obtain digital images of the retina, and the developed software (ALTAIR) will be used to automatically calculate the calibre of the retinal vessels, the vascularised area and the branching pattern. For software validation, the intraobserver and interobserver reliability, the concurrent validity of the vascular structure and function, as well as the association between the estimated retinal parameters and the evolution or onset of new lesions in the target organs or cardiovascular diseases will be examined. Ethics and dissemination The study has been approved by the clinical research ethics committee of the healthcare area of Salamanca. All study participants will sign an informed consent to agree to participate in the study in compliance with the Declaration of Helsinki and the WHO standards for observational studies. Validation of this tool will provide greater reliability to the analysis of retinal vessels by decreasing the intervention of the observer and will result in increased validity through the use of additional information, especially in the areas of vascularisation and vessel branching patterns. Trial registration number Clinical Trials.gov Identifier: NCT02087605. PMID:25468505

  7. Validation of Physical Activity Tracking via Android Smartphones Compared to ActiGraph Accelerometer: Laboratory-Based and Free-Living Validation Studies

    PubMed Central

    Buman, Matthew P; Grieco, Lauren; Rosenberger, Mary; Winter, Sandra J; Haskell, William; King, Abby C

    2015-01-01

    Background There is increasing interest in using smartphones as stand-alone physical activity monitors via their built-in accelerometers, but there is presently limited data on the validity of this approach. Objective The purpose of this work was to determine the validity and reliability of 3 Android smartphones for measuring physical activity among midlife and older adults. Methods A laboratory (study 1) and a free-living (study 2) protocol were conducted. In study 1, individuals engaged in prescribed activities including sedentary (eg, sitting), light (sweeping), moderate (eg, walking 3 mph on a treadmill), and vigorous (eg, jogging 5 mph on a treadmill) activity over a 2-hour period wearing both an ActiGraph and 3 Android smartphones (ie, HTC MyTouch, Google Nexus One, and Motorola Cliq). In the free-living study, individuals engaged in usual daily activities over 7 days while wearing an Android smartphone (Google Nexus One) and an ActiGraph. Results Study 1 included 15 participants (age: mean 55.5, SD 6.6 years; women: 56%, 8/15). Correlations between the ActiGraph and the 3 phones were strong to very strong (ρ=.77-.82). Further, after excluding bicycling and standing, cut-point derived classifications of activities yielded a high percentage of activities classified correctly according to intensity level (eg, 78%-91% by phone) that were similar to the ActiGraph’s percent correctly classified (ie, 91%). Study 2 included 23 participants (age: mean 57.0, SD 6.4 years; women: 74%, 17/23). Within the free-living context, results suggested a moderate correlation (ie, ρ=.59, P<.001) between the raw ActiGraph counts/minute and the phone’s raw counts/minute and a strong correlation on minutes of moderate-to-vigorous physical activity (MVPA; ie, ρ=.67, P<.001). Results from Bland-Altman plots suggested close mean absolute estimates of sedentary (mean difference=–26 min/day of sedentary behavior) and MVPA (mean difference=–1.3 min/day of MVPA) although there was large variation. Conclusions Overall, results suggest that an Android smartphone can provide comparable estimates of physical activity to an ActiGraph in both a laboratory-based and free-living context for estimating sedentary and MVPA and that different Android smartphones may reliably confer similar estimates. PMID:25881662

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

    ERIC Educational Resources Information Center

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

    2012-01-01

    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…

  9. Validity and feasibility of a digital diet estimation method for use with preschool children: a pilot study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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. Preschool children and their caregivers participated in validation (n=22) and feasibility (n=24) pilot studies. Validity was determined in the metabolic...

  10. Risser patient satisfaction scale: a validation study in Greek cancer patients

    PubMed Central

    2012-01-01

    Background The current healthcare climate is characterized by a constant battle for the provision of quality care with limited resources and with patient satisfaction receiving increased attention, there is a need for reliable and valid assessment measures. This study describes the adaptation, testing and validation of the Risser Patient satisfaction Scale in an oncology care setting in Greece. The rationale for this study lies in the scarcity of such measures in the Greek language. Methods This is a test retest validation study in Greece. Data were collected from 298 hospitalized cancer patients. The validation methodology included the assessment of the item internal consistency, using the Cronbach alpha coefficient. The test-retest reliability was tested by the Kappa correlation coefficient. Results The scale demonstrated very good psychometric properties. The internal consistency of the instrument was good, Cronbach’s alpha was found to be 0.78 (p<0.001) and Kappa coefficient for reproducibility was found to be K=0.89 (95% CI: 0.83-0.91 p<0.0001). Conclusion The findings demonstrated strong agreement of the scale, suggesting that the Greek version offers substantial reliability. This study provides a valid and reliable tool to assess patient satisfaction in oncology settings. Means to monitor patient satisfaction, a key aspect of the policy agenda for quality care remain important for nurse leaders to develop better care in oncology settings. PMID:23190625

  11. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 33 2012-07-01 2012-07-01 false Submission of study plans and conduct... RULES Implementation, Enforcement and Modification of Consent Agreements § 790.62 Submission of study... pursuant to a consent agreement shall submit a study plan no later than 45 days prior to the initiation...

  12. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Submission of study plans and conduct... RULES Implementation, Enforcement and Modification of Consent Agreements § 790.62 Submission of study... pursuant to a consent agreement shall submit a study plan no later than 45 days prior to the initiation...

  13. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 33 2013-07-01 2013-07-01 false Submission of study plans and conduct... RULES Implementation, Enforcement and Modification of Consent Agreements § 790.62 Submission of study... pursuant to a consent agreement shall submit a study plan no later than 45 days prior to the initiation...

  14. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Submission of study plans and conduct... RULES Implementation, Enforcement and Modification of Consent Agreements § 790.62 Submission of study... pursuant to a consent agreement shall submit a study plan no later than 45 days prior to the initiation...

  15. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 32 2014-07-01 2014-07-01 false Submission of study plans and conduct... RULES Implementation, Enforcement and Modification of Consent Agreements § 790.62 Submission of study... pursuant to a consent agreement shall submit a study plan no later than 45 days prior to the initiation...

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

    ERIC Educational Resources Information Center

    Hegde, Archana V.; Cassidy, Deborah J.

    2009-01-01

    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…

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

    ERIC Educational Resources Information Center

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

    2009-01-01

    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

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

    ERIC Educational Resources Information Center

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

    2009-01-01

    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…

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

    ERIC Educational Resources Information Center

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

    2006-01-01

    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…

  20. An optimal guarding scheme for thermal conductivity measurement using a guarded cut-bar technique, part 1 experimental study

    SciTech Connect

    Xing, Changhu; Jensen, Colby; Folsom, Charles; Ban, Heng; Marshall, Douglas W.

    2014-01-01

    In the guarded cut-bar technique, a guard surrounding the measured sample and reference (meter) bars is temperature controlled to carefully regulate heat losses from the sample and reference bars. Guarding is typically carried out by matching the temperature profiles between the guard and the test stack of sample and meter bars. Problems arise in matching the profiles, especially when the thermal conductivitiesof the meter bars and of the sample differ, as is usually the case. In a previous numerical study, the applied guarding condition (guard temperature profile) was found to be an important factor in measurement accuracy. Different from the linear-matched or isothermal schemes recommended in literature, the optimal guarding condition is dependent on the system geometry and thermal conductivity ratio of sample to meter bar. To validate the numerical results, an experimental study was performed to investigate the resulting error under different guarding conditions using stainless steel 304 as both the sample and meter bars. The optimal guarding condition was further verified on a certified reference material, pyroceram 9606, and 99.95% pure iron whose thermal conductivities are much smaller and much larger, respectively, than that of the stainless steel meter bars. Additionally, measurements are performed using three different inert gases to show the effect of the insulation effective thermal conductivity on measurement error, revealing low conductivity, argon gas, gives the lowest error sensitivity when deviating from the optimal condition. The result of this study provides a general guideline for the specific measurement method and for methods requiring optimal guarding or insulation.

  1. Validation Study: Response-Predictive Gene Expression Profiling of Glioma Progenitor Cells In Vitro

    PubMed Central

    Moeckel, Sylvia; Vollmann-Zwerenz, Arabel; Proescholdt, Martin; Brawanski, Alexander; Riemenschneider, Markus J.; Bogdahn, Ulrich; Bosserhoff, Anja-Katrin; Spang, Rainer; Hau, Peter

    2016-01-01

    Background In a previous publication we introduced a novel approach to identify genes that hold predictive information about treatment outcome. A linear regression model was fitted by using the least angle regression algorithm (LARS) with the expression profiles of a construction set of 18 glioma progenitor cells enhanced for brain tumor initiating cells (BTIC) before and after in vitro treatment with the tyrosine kinase inhibitor Sunitinib. Profiles from treated progenitor cells allowed predicting therapy-induced impairment of proliferation in vitro. Prediction performance was validated in leave one out cross validation. Methods In this study, we used an additional validation set of 18 serum-free short-term treated in vitro cell cultures to test the predictive properties of the signature in an independent cohort. We assessed proliferation rates together with transcriptome-wide expression profiles after Sunitinib treatment of each individual cell culture, following the methods of the previous publication. Results We confirmed treatment-induced expression changes in our validation set, but our signature failed to predict proliferation inhibition. Neither re-calculation of the combined dataset with all 36 BTIC cultures nor separation of samples into TCGA subclasses did generate a proliferation prediction. Conclusion Although the gene signature published from our construction set exhibited good prediction accuracy in cross validation, we were not able to validate the signature in an independent validation data set. Reasons could be regression to the mean, the moderate numbers of samples, or too low differences in the response to proliferation inhibition in the validation set. At this stage and based on the presented results, we conclude that the signature does not warrant further developmental steps towards clinical application. PMID:26978262

  2. Predictive Validity of the International Hospital Outcomes Study Questionnaire: An RN4CAST Pilot Study

    PubMed Central

    Bruyneel, Luk; Van den Heede, Koen; Diya, Luwis; Aiken, Linda; Sermeus, Walter

    2009-01-01

    Purpose To study the predictive validity of the instrument used in the International Hospital Outcomes Study (IHOS) for an upcoming EU-funded project (RN4CAST), which will indicate the effect of the nursing work environment and nursing staff deployment on nurse recruitment, retention, and productivity; and on patient outcomes in 11 European countries. Methods Cross-sectional analysis of data from 179 nurses (75% response rate) who completed an IHOS-like nurse survey questionnaire, which included the Revised Nursing Work Index and the Maslach Burnout Inventory. The nurses worked in four Belgian acute-care hospitals. Logistic regression modeling was performed to explore associations between nurse-perceived outcomes and nursing work environment factors that were checked with confirmatory factor analysis. Findings We confirmed associations between nurse-perceived outcomes and the following nursing work environment factors: nurse-physician relationship; staffing, and resource adequacy; and nurse manager ability, leadership, and support of nurses. A 1-point increase in the rating of the factor nurse-physician relationship was significantly associated with a 2.5-fold (OR, 2.53; 95% CI, 1.29–4.93; p<0.01) increase in the odds of reporting high job satisfaction and with a fourfold (OR, 4.02; 95% CI, 1.85–8.70; p<0.001) increase in the odds of reporting excellent nurse-perceived quality of care. A 1-point increase in the rating of the factor staffing and resource adequacy was significantly associated with an approximate threefold (OR, 2.81; 95% CI, 1.38–5.72; p<0.01) increase in the odds of reporting high job satisfaction and with a fourfold (OR, 0.23; 95% CI, 0.12–0.47; p<0.001) decrease in the odds of reporting burnout. Conclusions The predictive validity of the IHOS instrument was supported by the confirmation of key factors, which were previously identified by previous international research, and by the finding of similar associations between these factors and nurse-perceived outcomes. The IHOS questionnaire that will be used in the RN4CAST project is robust and psychometrically sound. Clinical Relevance The RN4CAST consortium, consisting of members from 15 countries, will use a similar instrument to that used in the International Hospital Outcomes study to measure the nursing work environment. This information will be linked with patients’ experiences and data extracted from routinely collected hospital discharge data. RN4CAST will show the important role of nursing staff in providing high quality care and allow refinement of current forecasting models for personnel planning in nursing. PMID:19538705

  3. Vapor sensing mechanism of acid on copper phthalocyanine thin films studied by electrical conductivity

    NASA Astrophysics Data System (ADS)

    Singh, Sukhwinder; Saini, G. S. S.; Tripathi, S. K.

    2013-06-01

    The electrical conductivity of thin films of iron phthalocyanine on glass substrates by thermal evaporation technique have been investigated. The electrical conductivity of thin films of these complexes changes when exposed to oxidizing and reducing gases such as halogens, ammonia, water and NOX. Thermal activation energy in the intrinsic region and impurity scattering region can be calculated by using Arrhenius plot. The dark conductivity and photoconductivity have been taken at different temperatures in the range 312-389 K. These films have been studied as chemical sensors for dilute sulphuric acid.

  4. A Validity and Reliability Study on the Development of the Values Scale in Turkey

    ERIC Educational Resources Information Center

    Dilmac, Bulent; Aricak, Osman Tolga; Cesur, Sevim

    2014-01-01

    The purpose of the present study is to examine the initial psychometric properties of the Values Scale for adults. While developing the first stage of the Values Scale, open-ended data on the values held by 216 university students were obtained. During the second stage, the validity and reliability studies of the 60-item Values Scale obtained by…

  5. Developing a Scale for Innovation Management at Schools: A Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Bulbul, Tuncer

    2012-01-01

    The purpose of this study is to develop a valid and reliable assessment tool for use in determining the competency beliefs of school administrators about innovation management. The scale applied to a study group of 216 school administrators, after work Centered on assessing intelligibility and specialized opinion. Exploratory and confirmatory…

  6. The Scales of Psychological Well-Being: A Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Akin, Ahmet

    2008-01-01

    This study investigated the validity and reliability of the Turkish version of the Scales of Psychological Well-being (Ryff, 1989a). The sample of the study consists of 1214 university students. Results of language equivalency showed that correlations between the Turkish and English forms were 0.94 for autonomy, 0.97 for environmental mastery,…

  7. Development and Validation of the Short Use of Creative Cognition Scale in Studying

    ERIC Educational Resources Information Center

    Rogaten, Jekaterina; Moneta, Giovanni B.

    2015-01-01

    This paper reports the development and validation of a short Use of Creative Cognition Scale in Studying (UCCS) that was inspired by the Cognitive Processes Associated with Creativity (CPAC) scale. In Study 1, items from two of the six subscales of the CPAC were excluded due to conceptual and psychometric issues to create a 21-item CPAC scale,…

  8. 40 CFR 152.93 - Citation of a previously submitted valid study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Citation of a previously submitted... Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An applicant may... the citation is necessary. (b) Study previously submitted by another person. If the applicant is...

  9. 40 CFR 152.93 - Citation of a previously submitted valid study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Citation of a previously submitted... Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An applicant may... the citation is necessary. (b) Study previously submitted by another person. If the applicant is...

  10. 40 CFR 152.93 - Citation of a previously submitted valid study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Citation of a previously submitted... Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An applicant may... the citation is necessary. (b) Study previously submitted by another person. If the applicant is...

  11. 40 CFR 152.93 - Citation of a previously submitted valid study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Citation of a previously submitted... and Protection of Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An... documentation other than the citation is necessary. (b) Study previously submitted by another person. If...

  12. 40 CFR 152.93 - Citation of a previously submitted valid study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Citation of a previously submitted... Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An applicant may... the citation is necessary. (b) Study previously submitted by another person. If the applicant is...

  13. Sources of Validity Evidence for Educational and Psychological Tests: A Follow-Up Study

    ERIC Educational Resources Information Center

    Cizek, Gregory J.; Bowen, Daniel; Church, Keri

    2010-01-01

    This study followed up on previous work that examined the incidence of reporting evidence based on test consequences in "Mental Measurements Yearbook". In the present study, additional possible outlets for what has been called "consequential validity" evidence were investigated, including all articles published in the past 10 years in several…

  14. The Depression Anxiety and Stress Scale (DASS): The Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Akin, Ahmet; Cetin, Bayram

    2007-01-01

    This study investigated the validity and reliability of the Turkish version of the Depression Anxiety Stress Scale (DASS). The sample of the study consisted of 590 university students, 121 English teachers and 136 emotionally disturbed individuals who sought treatment in various clinics and counseling centers. Factor loadings of the scale ranged…

  15. A Validity and Reliability Study of the Online Cooperative Learning Attitude Scale (OCLAS)

    ERIC Educational Resources Information Center

    Korkmaz, Ozgen

    2012-01-01

    Determination of students' attitudes towards online cooperative learning is an important issue, which has not been studied adequately. In the literature, there are few scales to measure the attitude towards online cooperative learning for which validity and reliability have been proven. The main purpose of this study is to develop an attitude…

  16. An Attitude Scale for Smart Board Use in Education: Validity and Reliability Studies

    ERIC Educational Resources Information Center

    Sad, Suleyman Nihat

    2012-01-01

    The main purpose of this study was to develop an instrument to measure the attitudes of elementary students towards smart board (SB) use in education. A sequential exploratory mixed method was used. So the study started with a qualitative approach to establish the content and face validity of the scale, followed by a quantitative approach to test

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

    ERIC Educational Resources Information Center

    Pfeiffer, Steven; Petscher, Yaacov; Kumtepe, Alper

    2008-01-01

    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…

  18. The Student Risk Screening Scale for Early Childhood: An Initial Validation Study

    ERIC Educational Resources Information Center

    Lane, Kathleen Lynne; Oakes, Wendy Peia; Menzies, Holly Mariah; Major, Rebecca; Allegra, Laurie; Powers, Lisa; Schatschneider, Chris

    2015-01-01

    We report findings of two exploratory validation studies of a revised instrument: the "Student Risk Screening Scale for Early Childhood" version (SRSS-EC). The SRSS-EC was modified to reflect characteristics of externalizing and internalizing behaviors manifested by preschool-age children. In Study 1, we explored the reliability of…

  19. A Validation and Reliability Study of Community Service Activities Scale in Turkey: A Social Evaluation

    ERIC Educational Resources Information Center

    Demir, Özden; Kaya, Halil Ibrahim; Tasdan, Murat

    2014-01-01

    The purpose of this study is to test the reliability and validity of Community Service Activities Scale (CSAS) developed by Demir, Kaya and Tasdan (2012) with a view to identify perceptions of Faculty of Education students regarding community service activities. The participants of the study are 313 randomly chosen students who attend six…

  20. The Volunteer Satisfaction Index: A Validation Study in the Chinese Cultural Context

    ERIC Educational Resources Information Center

    Wong, Lok Ping; Chui, Wing Hong; Kwok, Yan Yuen

    2011-01-01

    Using a Hong Kong-sourced sample of 261 participants, this study set out to validate the Volunteer Satisfaction Index (VSI) in the Chinese cultural context and to evaluate its psychometric properties. The VSI was originally developed by Galindo-Kuhn and Guzley (2001) to measure the outcomes of volunteer experiences. In this study, exploratory…

  1. Water Awareness Scale for Pre-Service Science Teachers: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Filik Iscen, Cansu

    2015-01-01

    The role of teachers in the formation of environmentally sensitive behaviors in students is quite high. Thus, the water awareness of teachers, who represent role models for students, is rather important. The main purpose of this study is to identify the reliability and validity study outcomes of the Water Awareness Scale, which was developed to…

  2. An Attitude Scale for Smart Board Use in Education: Validity and Reliability Studies

    ERIC Educational Resources Information Center

    Sad, Suleyman Nihat

    2012-01-01

    The main purpose of this study was to develop an instrument to measure the attitudes of elementary students towards smart board (SB) use in education. A sequential exploratory mixed method was used. So the study started with a qualitative approach to establish the content and face validity of the scale, followed by a quantitative approach to test…

  3. A Validation and Reliability Study of Community Service Activities Scale in Turkey: A Social Evaluation

    ERIC Educational Resources Information Center

    Demir, zden; Kaya, Halil Ibrahim; Tasdan, Murat

    2014-01-01

    The purpose of this study is to test the reliability and validity of Community Service Activities Scale (CSAS) developed by Demir, Kaya and Tasdan (2012) with a view to identify perceptions of Faculty of Education students regarding community service activities. The participants of the study are 313 randomly chosen students who attend six

  4. Water Awareness Scale for Pre-Service Science Teachers: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Filik Iscen, Cansu

    2015-01-01

    The role of teachers in the formation of environmentally sensitive behaviors in students is quite high. Thus, the water awareness of teachers, who represent role models for students, is rather important. The main purpose of this study is to identify the reliability and validity study outcomes of the Water Awareness Scale, which was developed to

  5. A multicenter, cross-platform clinical validation study of cancer cytogenomic arrays.

    PubMed

    Li, Marilyn M; Monzon, Federico A; Biegel, Jaclyn A; Jobanputra, Vaidehi; Laffin, Jennifer J; Levy, Brynn; Leon, Annette; Miron, Patricia; Rossi, Michael R; Toruner, Gokce; Alvarez, Karla; Doho, Gregory; Dougherty, Margaret J; Hu, Xiaofeng; Kash, Shera; Streck, Deanna; Znoyko, Iya; Hagenkord, Jill M; Wolff, Daynna J

    2015-11-01

    Cytogenomic microarray analysis (CMA) offers high resolution, genome-wide copy number information and is widely used in clinical laboratories for diagnosis of constitutional abnormalities. The Cancer Genomics Consortium (CGC) conducted a multiplatform, multicenter clinical validation project to compare the reliability and inter- and intralaboratory reproducibility of this technology for clinical oncology applications. Four specimen types were processed on three different microarray platforms-from Affymetrix, Agilent, and Illumina. Each microarray platform was employed at two independent test sites. The results were compared in a blinded manner with current standard methods, including karyotype, FISH, or morphology. Twenty-nine chronic lymphocytic leukemia blood, 34 myelodysplastic syndrome bone marrow, and 30 fresh frozen renal epithelial tumor samples were assessed by all six laboratories. Thirty formalin fixed paraffin embedded renal tumor samples were analyzed at the Affymetrix and Agilent test sites only. All study samples were initial diagnostic samples. Array data were analyzed at each participating site and were submitted to caArray for central analysis. Laboratory interpretive results were submitted to the central analysis team for comparison with the standard-of-care assays and for calculation of intraplatform reproducibility and cross-platform concordance. The results demonstrated that the three microarray platforms 1) detect clinically actionable genomic changes in cancer compatible to standard-of-care methods; 2) further define cytogenetic aberrations; 3) identify submicroscopic alterations and loss of heterozygosity (LOH); and 4) yield consistent results within and between laboratories. Based on this study, the CGC concludes that CMA is a sensitive and reliable technique for copy number and LOH assessment that may be used for clinical oncology genomic analysis. PMID:26454669

  6. Reliability and validity of 6MWT for outpatients with schizophrenia: A preliminary study.

    PubMed

    Gomes, Eluana; Bastos, Tânia; Probst, Michel; Ribeiro, José Carlos; Silva, Gustavo; Corredeira, Rui

    2016-03-30

    Although the 6-minute walk test (6MWT) has been widely used in patients with schizophrenia, there is a lack of scientific evidence about its reliability and validity in this population. The first goal of this study was to explore the test-retest reliability of the 6MWT and to identify the associated parameters that contribute to the variability of the distance walked during the 6MWT in outpatients with schizophrenia. The second goal was to assess the criterion validity of the 6MWT in men with schizophrenia. Fifty one outpatients with schizophrenia participated in the study. To test-retest reliability (men=39; women=12), participants performed the 6MWT twice within 3 days interval. To test criterion validity (men=13), peak oxygen uptake (VO2peak) was measured on a treadmill. For the associated parameters with the distance walked (n=51), medications use, smoking behavior, body and bone composition, and physical activity levels were analyzed. No significant differences between the means of the two 6MWTs were found. The intraclass correlation coefficient was 0.94 indicating good reliability. 6MWT correlated significantly with VO2peak (r=0.67) indicating criterion validity. Height, body fat mass, smoking behavior and minutes of PA/week were significantly associated with the 6MWT. Results suggest that 6MWT shows good reliability for individuals with schizophrenia and good validity for the small sample of male participants in this study. PMID:26921049

  7. Nerve conduction in relation to vibration exposure - a non-positive cohort study

    PubMed Central

    2010-01-01

    Background Peripheral neuropathy is one of the principal clinical disorders in workers with hand-arm vibration syndrome. Electrophysiological studies aimed at defining the nature of the injury have provided conflicting results. One reason for this lack of consistency might be the sparsity of published longitudinal etiological studies with both good assessment of exposure and a well-defined measure of disease. Against this background we measured conduction velocities in the hand after having assessed vibration exposure over 21 years in a cohort of manual workers. Methods The study group consisted of 155 male office and manual workers at an engineering plant that manufactured pulp and paper machinery. The study has a longitudinal design regarding exposure assessment and a cross-sectional design regarding the outcome of nerve conduction. Hand-arm vibration dose was calculated as the product of self-reported occupational exposure, collected by questionnaire and interviews, and the measured or estimated hand-arm vibration exposure in 1987, 1992, 1997, 2002, and 2008. Distal motor latencies in median and ulnar nerves and sensory nerve conduction over the carpal tunnel and the finger-palm segments in the median nerve were measured in 2008. Before the nerve conduction measurement, the subjects were systemically warmed by a bicycle ergometer test. Results There were no differences in distal latencies between subjects exposed to hand-arm vibration and unexposed subjects, neither in the sensory conduction latencies of the median nerve, nor in the motor conduction latencies of the median and ulnar nerves. Seven subjects (9%) in the exposed group and three subjects (12%) in the unexposed group had both pathological sensory nerve conduction at the wrist and symptoms suggestive of carpal tunnel syndrome. Conclusion Nerve conduction measurements of peripheral hand nerves revealed no exposure-response association between hand-arm vibration exposure and distal neuropathy of the large myelinated fibers in a cohort of male office and manual workers. PMID:20642848

  8. Intracardiac conduction defects in dystrophia myotonica. Electrophysiological study of 12 cases.

    PubMed Central

    Komajda, M; Frank, R; Vedel, J; Fontaine, G; Petitot, J C; Grosgogeat, Y

    1980-01-01

    Twelve patients with dystrophia myotonica had cardiac electrphysiological study for conduction disturbances (five cases) or for syncope (seven cases). Conduction disturbances were found in each case, being intranodal in two cases, intra-Hisian in three cases, or diffuse in seven cases. These findings are in agreement with those previously reported, and may be related to the high incidence of sudden death in these patients. Pacemakers are advocated in symptomatic patients, and in some asymptomatic patients with severe and diffuse lesions. PMID:7437178

  9. Considerations for conducting epidemiologic case-control studies of cancer in developing countries.

    PubMed

    Brinton, L A; Herrero, R; Brenes, M; Montalván, P; de la Guardia, M E; Avila, A; Domínguez, I L; Basurto, E; Reeves, W C

    1991-01-01

    The challenges involved in conducting epidemiologic studies of cancer in developing countries can be and often are unique. This article reports on our experience in performing a case-control study of invasive cervical cancer in four Latin American countries (Columbia, Costa Rica, Mexico, and Panama), the summary medical results of which have been published in a previous issue of this journal (1). The study involved a number of principal activities--mainly selecting, conducting interviews with, and obtaining appropriate biologic specimens from 759 cervical cancer patients, 1,467 matched female controls, and 689 male sex partners of monogamous female subjects. This presentation provides an overview of the planning and methods used to select the subjects, conduct the survey work, and obtain complete and effectively unbiased data. It also points out some of the important advantages and disadvantages of working in developing areas similar to those serving as locales for this study. PMID:2054548

  10. AC conductivity and Dielectric Study of Chalcogenide Glasses of Se-Te-Ge System

    NASA Astrophysics Data System (ADS)

    Salman, Fathy

    2004-01-01

    The ac conductivity and dielectric properties of glassy system SexTe79 - xGe21, with x = 11, 14, 17 at.%, has been studied at temperatures 300 to 450 K and over a wide range of frequencies (50 Hz to 500 kHz). Experimental results indicate that the ac conductivity and the dielectric constants depend on temperature, frequency and Se content. The conductivity as a function of frequency exhibited two components: dc conductivity s dc, and ac conductivity s ac, where s ac ˜ w s. The mechanism of ac conductivity can be reasonably interpreted in terms of the correlated barrier hopping model (CBH). The activation energies are estimated and discussed. The dependence of ac conductivity and dielectric constants on the Se content x can be interpreted as the effect of Se fraction on the positional disorder. The impedance plot at each temperature appeared as a semicircle passes through the origin. Each semicircle is represented by an equivalent circuit of parallel resistance Rb and capacitance Cb.

  11. New technologies to support NASA's Mission to Planet Earth satellite remote sensing product validation: use of an unmanned autopiloted vehicle (UAV) as a platform to conduct remote sensing

    NASA Astrophysics Data System (ADS)

    Coronado, Patrick L.; Stetina, Fran; Jacob, Dan

    1998-08-01

    As part of the US Global Change program, NASA has initiated its Mission to Planet Earth Program (MTPE) which requires continuous global satellite measurements over an extended 15 years period. Various US and International Earth Observing Satellites will be launched during this period. To ensure continuity of the measurements, a significant instrument calibration and product validation effort is required and is planned as part of this program. However, the validation of satellite products requires extensive ground truthing which is both costly and time consuming and in many cases limited to specific calibration/validation areas. Thus there is a need to extend this validation effort to include more participants and provide new, more cost effective technologies to support the validation effort. The use of unmanned autopiloted vehicles (UAV) and new miniature high performance instruments have been identified as providing this needed additional capability. This paper discusses the development of a UAV, associated avionics and preliminary remote sensing instruments to support the extension of ground truthing and product validation of NASA's MTPE Programs, specifically, earth observing system. The UAV being described is based on thrust vectoring capabilities and a single-axis pivoted wing or 'freewing' design. This unique UAV system is illustrated along with the proposed autonomous avionics and preliminary remote sensing payloads.

  12. Quantification of construction waste prevented by BIM-based design validation: Case studies in South Korea.

    PubMed

    Won, Jongsung; Cheng, Jack C P; Lee, Ghang

    2016-03-01

    Waste generated in construction and demolition processes comprised around 50% of the solid waste in South Korea in 2013. Many cases show that design validation based on building information modeling (BIM) is an effective means to reduce the amount of construction waste since construction waste is mainly generated due to improper design and unexpected changes in the design and construction phases. However, the amount of construction waste that could be avoided by adopting BIM-based design validation has been unknown. This paper aims to estimate the amount of construction waste prevented by a BIM-based design validation process based on the amount of construction waste that might be generated due to design errors. Two project cases in South Korea were studied in this paper, with 381 and 136 design errors detected, respectively during the BIM-based design validation. Each design error was categorized according to its cause and the likelihood of detection before construction. The case studies show that BIM-based design validation could prevent 4.3-15.2% of construction waste that might have been generated without using BIM. PMID:26754615

  13. The Iranian version of the Premenstrual Symptoms Screening Tool (PSST): a validation study.

    PubMed

    Hariri, Fatemeh Zahra; Moghaddam-Banaem, Lida; Siah Bazi, Shiva; Saki Malehi, Amal; Montazeri, Ali

    2013-12-01

    The objective of the current study was to translate and test psychometric properties of the Premenstrual Symptoms Screening Tool (PSST) in Iran. Using a standard "forward-backward" procedure, the English version of PSST was translated into Persian. A random sample of university students aged 18 years and over completed the questionnaire in Tehran, Iran. Psychometric properties of the Iranian version of PSST were assessed by performing reliability (internal consistency) and validity analyses [Content Validity Ratio (CVR) and Content Validity Index (CVI)]. In all, 925 female students took part in the study. Of these, 284 (30.7 %) had premenstrual syndrome (PMS) and 119 (12.9 %) had premenstrual dysphoric disorder (PMDD). Reliability of the PSST as measured by internal consistency was found to be satisfactory (Cronbach's alpha coefficient, 0.93). The content validity as assessed by CVR and CVI were desirable (0.7 and 0.8, respectively). The Iranian version of PSST seems to be a reliable and valid measure of detecting PMS and PMDD in Iranian young female populations. PMID:23974654

  14. Solid State Ionics: Studies of Lithium-Conducting Sulfide Glasses and a Superconducting Oxide Compound.

    NASA Astrophysics Data System (ADS)

    Ahn, Byung Tae

    The first part of this work studies lithium-conducting sulfide glasses for battery applications, while the second part studies the thermodynamic properties of a superconducting oxide compound by using an oxide electrolyte. Lithium conducting glasses based on the SiS _2-Li_2S system are possible solid electrolytes for high-energy-density lithium batteries. The foremost requirement for solid electrolytes is that they should have high ionic conductivities. Unfortunately, most crystalline lithium conductors have low ionic conductivities at room temperature. However, glass ionic conductors show higher ionic conductivities than do crystalline forms of the same material. In addition to higher ionic conductivities, glasses appear to have several advantages over crystalline materials. These advantages include isotropic conductivity, absence of grain boundary effects, ease of glass forming, and the potential for a wide range of stability to oxidizing and reducing conditions. Using pyrolitic graphite-coated quartz ampoules, new ternary compounds and glasses in the SiS_2 -Li_2S system were prepared. Several techniques were used to characterize the materials: powder x-ray diffraction, differential thermal analysis, differential scanning calorimetry, and AC impedance spectroscopy. The measured lithium conductivity of the sulfide glasses was one of the highest among the known solid lithium conductors. Measuring the equilibrium open circuit voltages assisted in determining the electrochemical stabilities of the ternary compounds and glasses with respect to pure Li. Forming associated structural defects in the sulfide glass results in the wide range of stoichiometry, the low electronic conductivity, the high ionic conductivity, and the narrow electrochemical stability of the glass. Both the higher carrier concentration and the higher mobility enhances the ionic conductivity of the glasses compared to the crystalline phase. The composition dependence of the ionic conductivity indicates that the mobility change, rather than the carrier concentration change, is the dominant factor. The narrow electrochemical stability window of the glass results from the formation of the associated defects in the glasses; thus the Fermi level in the glasses is fixed near the intrinsic energy level. A solid-state ionic technique called oxygen coulometric titration solves these problems. Using this technique, the thermodynamic stability, the oxygen stoichiometry, and the effects of the oxygen stoichiometry and the cooling rate on superconductivity of the YBa_2Cu _3O_{rm 7-x} compound were investigated. (Abstract shortened with permission of author.).

  15. Characterizing Measurement Error in Test Scores across Studies: A Tutorial on Conducting "Reliability Generalization" Analyses.

    ERIC Educational Resources Information Center

    Henson, Robin K.; Thompson, Bruce

    Given the potential value of reliability generalization (RG) studies in the development of cumulative psychometric knowledge, the purpose of this paper is to provide a tutorial on how to conduct such studies and to serve as a guide for researchers wishing to use this methodology. After some brief comments on classical test theory, the paper…

  16. 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...

  17. 42 CFR 90.8 - Conduct of health assessments and health effects studies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Conduct of health assessments and health effects studies. 90.8 Section 90.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND...

  18. 76 FR 70122 - Plan for Conduct of 2012 Electric Transmission Congestion Study

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-10

    ... relief (TLR) actions. Historic energy flows. Current and projected electric supply and generation plans... for Conduct of 2012 Electric Transmission Congestion Study AGENCY: Office of Electricity Delivery and... Energy (Department or DOE) to complete a study of electric transmission congestion every three years....

  19. Study of the Kinetics of an S[subscript N]1 Reaction by Conductivity Measurement

    ERIC Educational Resources Information Center

    Marzluff, Elaine M.; Crawford, Mary A.; Reynolds, Helen

    2011-01-01

    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…

  20. Study of the Kinetics of an S[subscript N]1 Reaction by Conductivity Measurement

    ERIC Educational Resources Information Center

    Marzluff, Elaine M.; Crawford, Mary A.; Reynolds, Helen

    2011-01-01

    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