Science.gov

Sample records for validation studies conducted

  1. Conducting Licensure Validity Studies: The Need To Broaden the Evidentiary Base.

    ERIC Educational Resources Information Center

    Poggio, John P.; Glasnapp, Douglas R.; Green, Sam B.; Tollefson, Nona

    Findings are reported from a series of comprehensive and detailed empirical investigations that evaluated four different teacher certification paper-and-pencil tests through a typical content validation method and from three distinct and independent empirical validation studies of these devices. These latter studies can be understood as providing…

  2. 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

  3. 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

  4. WISC-R incentives and the academic achievement of conduct disordered adolescent females: a validity study.

    PubMed

    Saigh, P A; Antoun, F T

    1983-09-01

    Selected and randomly assigned 51 institutionalized conduct disordered adolescent females to one of three treatment conditions. Ss' responses to a short form of the WISC-R were followed by examiner praise, neutral feedback, or token reinforcement. A series of Pearson product-moment correlations were calculated between the scaled scores of the three treatment groups and their GPAs. The results revealed that the identified subtests, regardless of treatment condition, were poor predictors of achievement. The correlations were discussed in view of the association between the selected subtests and the curricula of the special education classes, observed variations between the WISC-R treatment scores, and the special characteristics of the Ss.

  5. Validation of a two-step quality control approach for a large-scale human urine metabolomic study conducted in seven experimental batches with LC/QTOF-MS.

    PubMed

    Demetrowitsch, Tobias J; Petersen, Beate; Keppler, Julia K; Koch, Andreas; Schreiber, Stefan; Laudes, Matthias; Schwarz, Karin

    2015-01-01

    After his study of food science at the Rheinische Friedrich-Wilhelms University of Bonn, Tobias J Demetrowitsch obtained his doctoral degree in the research field of metabolomics at the Christian-Albrechts-University of Kiel. The present paper is part of his doctoral thesis and describes an extended strategy to evaluate and verify complex or large-scale experiments and data sets. Large-scale studies result in high sample numbers, requiring the analysis of samples in different batches. So far, the verification of such LC-MS-based metabolomics studies is difficult. Common approaches have not provided a reliable validation procedure to date. This article shows a novel verification process for a large-scale human urine study (analyzed by a LC/QToF-MS system) using a two-step validation procedure. The first step comprises a targeted approach that aims to examine and exclude statistical outliers. The second step consists of a principle component analysis, with the aim of a tight cluster of all quality controls and a second for all volunteer samples. The applied study design provides a reliable two-step validation procedure for large-scale studies and additionally contains an inhouse verification procedure. PMID:25558939

  6. [Methods for quantifying phasic skin conductance amplitudes: threats to validity?].

    PubMed

    Zimmer, H; Vossel, G

    1993-01-01

    Two methods of determining the event-related skin conductance response (SCR) amplitude are in common use. In one of these, the difference in conductance between the point of onset and the peak level of a single wave is measured (method 1). The second approach is to determine the difference between two measures, one characterizing the prestimulus level, the other the highest conductance point of the SCR reached within a fixed period following the stimulus (method 2). A problem with quantifying the SCR amplitude occurs when a SCR is elicited before an immediately preceding response has had time to recover, because in this case the two methods lead to quite different values. If the amplitude of each response is measured from its own individual deflection point, the measurable amplitude of the second response will be smaller when it occurs immediately after or in the ascending limb of the first response. The problem is most evident in situations with a high probability of response superimposition, such as when a large number of nonspecific responses occur at the same time as the SCRs. This is found in individuals with a high degree of electrodermal lability. Electrodermal lability refers to a psychophysiological construct that is operationally defined by the frequency of spontaneous electrodermal fluctuations. In the present study, we therefore systematically investigated the effects of the two score methods on SCR amplitude in relation to lability by analyzing electrodermal data from two habituation studies. As expected, several method-specific effects which were related to lability emerged. Results and questions concerning the relevance of the findings are discussed, with special emphasis on the validity of psychophysiological investigations.

  7. Validation of conducting wall models using magnetic measurements

    NASA Astrophysics Data System (ADS)

    Hanson, J. M.; Bialek, J.; Turco, F.; King, J.; Navratil, G. A.; Strait, E. J.; Turnbull, A.

    2016-10-01

    The impact of conducting wall eddy currents on perturbed magnetic field measurements is a key issue for understanding the measurement and control of long-wavelength MHD stability in tokamak devices. As plasma response models have growth in sophistication, the need to understand and resolve small changes in these measurements has become more important, motivating increased fidelity in simulations of externally applied fields and the wall eddy current response. In this manuscript, we describe thorough validation studies of the wall models in the mars-f and valen stability codes, using coil-sensor vacuum coupling measurements from the DIII-D tokamak (Luxon et al 2005 Fusion Sci. Technol. 48 807). The valen formulation treats conducting structures with arbitrary three-dimensional geometries, while mars-f uses an axisymmetric wall model and a spectral decomposition of the problem geometry with a fixed toroidal harmonic n. The vacuum coupling measurements have a strong sensitivity to wall eddy currents induced by time-changing coil currents, owing to the close proximities of both the sensors and coils to the wall. Measurements from individual coil and sensor channels are directly compared with valen predictions. It is found that straightforward improvements to the valen model, such as refining the wall mesh and simulating the vertical extent of the DIII-D poloidal field sensors, lead to good agreement with the experimental measurements. In addition, couplings to multi-coil, n  =  1 toroidal mode perturbations are calculated from the measurements and compared with predictions from both codes. The toroidal mode comparisons favor the fully three-dimensional simulation approach, likely because this approach naturally treats n  >  1 sidebands generated by the coils and wall eddy currents, as well as the n  =  1 fundamental.

  8. 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.

  9. 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

  10. 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.

  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.

  12. Conducting Simulation Studies in Psychometrics

    ERIC Educational Resources Information Center

    Feinberg, Richard A.; Rubright, Jonathan D.

    2016-01-01

    Simulation studies are fundamental to psychometric discourse and play a crucial role in operational and academic research. Yet, resources for psychometricians interested in conducting simulations are scarce. This Instructional Topics in Educational Measurement Series (ITEMS) module is meant to address this deficiency by providing a comprehensive…

  13. 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.

  14. 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.

  15. Content Validity Studies of Licensing Examinations.

    ERIC Educational Resources Information Center

    Smith, I. Leon; Hambleton, Ronald K.

    1990-01-01

    Implementing measurement specialists' ideas about content validity with licensure examinations and the problem of court litigation are discussed. Validity issues surfacing when sponsors of national licensure examinations conduct validity investigations are considered. Issues include local versus national focus on content validity, job analysis,…

  16. Critical validation studies of neurofeedback.

    PubMed

    Gruzelier, John; Egner, Tobias

    2005-01-01

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

  17. 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

    2016-07-01

    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.

  18. 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.

  19. 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.

  20. 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…

  1. Conducting a pilot study: case study of a novice researcher.

    PubMed

    Doody, Owen; Doody, Catriona M

    Pilot studies play a vital role in health research, but are often misused, mistreated and misrepresented. A well-conducted pilot study with clear aims and objectives within a formal framework ensures methodological rigour, can lead to higher-quality research and scientifically valid work that is publishable and can benefit patients and health service delivery. A pilot study contributes valuable information to assist researchers in the conduct of their study. Conducting a pilot study provides the researcher with the opportunity to develop and enhance the skills necessary before commencing the larger study. By conducting a pilot the researcher obtains preliminary data, can evaluate their data-analysis method and clarify the financial and human resources required. This article presents an overview of pilot studies, why they are conducted, what to consider when reporting pilot studies and the authors' experience of conducting a pilot study. To conduct a successful study, researchers need to develop their skills, choose the right methods and carefully plan for all aspects of the process. PMID:26618678

  2. 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

  3. 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.…

  4. Sexual narcissism: a validation study.

    PubMed

    Hurlbert, D F; Apt, C; Gasar, S; Wilson, N E; Murphy, Y

    1994-01-01

    Sexual narcissism, an egocentric pattern of sexual behavior, has recently been described in the literature and has been discovered to be associated with cluster B type personality disorders. Although the research seems to have validated sexual narcissism as a characteristic of borderline and histrionic personality disorders, it is yet to be tested with narcissistic personalities. In an effort to further explore this relationship as well as the validity of sexual narcissism, this study systematically compared a sample (ages 24-33 years) of males with narcissistic personality disorder with an adequately matched sample of males without personality disorders. As compared to the control group, narcissistic men were found to have significantly lower self-esteem, more negative attitudes toward sex, greater egocentric patterns of sexual behavior, more conservative or traditional gender-role orientation, and greater sexual preoccupation. Despite these findings, there were no significant differences between the groups on sexual depression and the narcissistic men evidenced significantly higher sexual esteem. Implications for these findings are discussed.

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 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...

  6. 49 CFR 40.91 - What validity tests must laboratories conduct on primary specimens?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 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...

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    SummaryA series of rising and falling head slug tests with different initial applied head differentials (ΔHo) were conducted in open fractured dolostone and sandstone boreholes using straddle packers isolating specific depth intervals (1.5 m length) to examine the influence of non-Darcian flow. The open holes were developed and inspected using video and acoustic televiewing (ATV) to ensure that evidence of skin effects due to drilling were absent. The transmissivity (T) values obtained from both the rising and falling head slug tests were very similar at low initial applied head; however, the T values were progressively smaller at larger ΔHo, suggesting error due to non-Darcian flow. Non-Darcian flow behavior was confirmed by constant head step tests conducted in the same test intervals where the injection rate (Q) vs. applied head (dH) relationship became non-linear at relatively low injection rates, and the non-Darcian data also resulted in lower T values. For a series of slug tests conducted at different ΔHo, non-Darcian flow effects gradually increased as ΔHo increased, consistent with the trends for constant head step tests conducted in the same test intervals. To maintain Darcian flow conditions in the fractured dolostone and sandstone tested in this study, ΔHo must be kept small, generally less than 0.2 m. This study demonstrates that by conducting both "stepped" slug tests and constant head step tests, the Darcian flow assumption for both types of tests can be rigorously validated. However, when only slug tests are conducted, it is necessary to conduct a series of "stepped" slug tests, including tests with small applied head differentials, to avoid errors due to non-Darcian flow.

  8. Conducting and Reporting Case Studies.

    ERIC Educational Resources Information Center

    Lichtman, Merilyn; Taylor, Satomi Izumi

    Issues and elements of case study research are explored and illustrated with the example of a case study of a kindergarten in a suburb of Tokyo (Japan). Case study research is a type of qualitative research that concentrates on a single unit or entity, with boundaries established by the researcher. The case is an example drawn from a larger class,…

  9. 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

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

    PubMed

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

    2016-01-05

    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.

  11. 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.

  12. Validity of diagnostic computer-based air and forehead bone conduction audiometry.

    PubMed

    Swanepoel, De Wet; Biagio, Leigh

    2011-04-01

    Computer-based audiometry allows for novel applications, including remote testing and automation, that may improve the accessibility and efficiency of hearing assessment in various clinical and occupational health settings. This study describes the validity of computer-based, diagnostic air and forehead bone conduction audiometry when compared wtih conventional industry standard audiometry in a sound booth environment. A sample of 30 subjects (19 to 77 years of age) was assessed with computer-based (KUDUwave 5000) and industry standard conventional audiometers (GSI 61) to compare air and bone conduction thresholds and test-retest reliability. Air conduction thresholds for the two audiometers corresponded within 5 dB or less in more than 90% of instances, with an average absolute difference of 3.5 dB (3.8 SD) and a 95% confidence interval of 2.6 to 4.5 dB. Bone conduction thresholds for the two audiometers corresponded within 10 dB or less in 92% of instances, with an average absolute difference of 4.9 dB (4.9 SD) and a 95% confidence interval of 3.6 to 6.1 dB. The average absolute test-retest threshold difference for bone conduction on the industry standard audiometer was 5.1 dB (5.3 SD) and for the computer-based audiometer 7.1 dB (6.4 SD). Computer-based audiometry provided air and bone conduction thresholds within the test-retest reliability limits of industry standard audiometry.

  13. 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.,…

  14. Predictive validity of childhood oppositional defiant disorder and conduct disorder: implications for the DSM-V.

    PubMed

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

    2010-11-01

    Data are presented from 3 studies of children and adolescents to evaluate the predictive validity of childhood oppositional defiant disorder (ODD) and conduct disorder (CD) as defined in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV; American Psychiatric Association, 1994) and the International Classification of Diseases, Version 10 (ICD-10; World Health Organization, 1992). The present analyses strongly support the predictive validity of these diagnoses by showing that they predict both future psychopathology and enduring functional impairment. Furthermore, the present findings generally support the hierarchical developmental hypothesis in DSM-IV that some children with ODD progress to childhood-onset CD, and some youth with CD progress to antisocial personality disorder (APD). Nonetheless, they reveal that CD does not always co-occur with ODD, particularly during adolescence. Importantly, the present findings suggest that ICD-10 diagnostic criteria for ODD, which treat CD symptoms as ODD symptoms when diagnostic criteria for CD are not met, identify more functionally impaired children than the more restrictive DSM-IV definition of ODD. Filling this "hole" in the DSM-IV criteria for ODD should be a priority for the DSM-V. In addition, the present findings suggest that although the psychopathic trait of interpersonal callousness in childhood independently predicts future APD, these findings do not confirm the hypothesis that callousness distinguishes a subset of children with CD with an elevated risk for APD.

  15. 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…

  16. Cable SGEMP Code Validation Study

    SciTech Connect

    Ballard, William Parker

    2013-05-01

    This report compared data taken on the Modular Bremsstrahlung Simulator using copper jacketed (cujac) cables with calculations using the RHSD-RA Cable SGEMP analysis tool. The tool relies on CEPXS/ONBFP to perform radiation transport in a series of 1D slices through the cable, and then uses a Green function technique to evaluate the expected current drive on the center conductor. The data were obtained in 2003 as part of a Cabana verification and validation experiment using 1-D geometries, but were not evaluated until now. The agreement between data and model is not adequate unless gaps between the dielectric and outer conductor (ground) are assumed, and these gaps are large compared with what is believed to be in the actual cable.

  17. 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...

  18. A Re-analysis of Published Differential Validity Studies.

    ERIC Educational Resources Information Center

    Ruch, William W.

    A survey of recent literature was undertaken to locate validity studies of paper-and-pencil tests which met the following criteria: (1) Studies were conducted in a business or industrial (i.e. non-education, non-military) setting; (2) Separate statistics were available for blacks and whites; (3) Race was not confounded with some outside variable…

  19. Design and Validation of a High-Temperature Comparative Thermal-Conductivity Measurement System

    SciTech Connect

    Jeff Phillips; Colby Jensen; C Xing; H. Ban

    2012-02-01

    A measurement system has been designed and built for the specific application of measuring the effective thermal conductivity of a composite, nuclear-fuel compact (small cylinder) over a temperature range of 100 C to 800 C. Because of the composite nature of the sample as well as the need to measure samples pre- and postirradiation, measurement must be performed on the whole compact non-destructively. No existing measurement system is capable of obtaining its thermal conductivity in a non-destructive manner. The designed apparatus is an adaptation of the guardedcomparative-longitudinal heat flow technique. The system uniquely demonstrates the use of a radiative heat sink to provide cooling which greatly simplifies the design and setup of such high-temperature systems. The design was aimed to measure thermalconductivity values covering the expected range of effective thermal conductivity of the composite nuclear fuel from 10W {center_dot} m{sup -1} {center_dot} K{sup -1} to 70W {center_dot} m{sup -1} {center_dot} K{sup -1}. Several materials having thermal conductivities covering this expected range have been measured for system validation, and results are presented. A comparison of the results has been made to data from existing literature.Additionally, an uncertainty analysis is presented finding an overall uncertainty in sample thermal conductivity to be 6%, matching well with the results of the validation samples.

  20. Cognitive Preferences: A Validation Study.

    ERIC Educational Resources Information Center

    Van den Berg, Euwe, Ed.; And Others

    1978-01-01

    This study successfully replicated and extended previous research on cognitive preferences of talented high school students, using the Science Cognitive Preference Inventory (SCPI). Four modes of cognitive preference were interpreted: (1) factual information or recall; (2) principles; (3) questioning; and (4) practical applications. (CP)

  1. 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.

  2. 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.

  3. 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…

  4. 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…

  5. Conductivity study of chitosan based nanocomposites

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

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

  6. 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

  7. Validity of conducting clinical dysphagia assessments for patients with normal to mild cognitive impairment via telerehabilitation.

    PubMed

    Ward, Elizabeth C; Sharma, Shobha; Burns, Clare; Theodoros, Deborah; Russell, Trevor

    2012-12-01

    To assess the validity of conducting clinical dysphagia assessments via telerehabilitation, 40 individuals with dysphagia from various etiologies were assessed simultaneously by a face-to-face speech-language pathologist (FTF-SLP) and a telerehabilitation SLP (T-SLP) via an Internet-based videoconferencing telerehabilitation system. Dysphagia status was assessed using a Clinical Swallowing Examination (CSE) protocol, delivered via a specialized telerehabilitation videoconferencing system and involving the use of an assistant at the patient's end of the consultation to facilitate the assessment. Levels of agreement between the FTF-SLP and T-SLP revealed that the majority of parameters reached set levels of clinically acceptable levels of agreement. Specifically, agreement between the T-SLP and FTF-SLP ratings for the oral, oromotor, and laryngeal function tasks revealed levels of exact agreement ranging from 75 to 100% (kappa = 0.36-1.0), while the parameters relating to food and fluid trials ranged in exact agreement from 79 to 100% (kappa = 0.61-1.0). Across the parameters related to aspiration risk and clinical management, exact agreement ranged between 79 and 100% (kappa = 0.49-1.0). The data show that a CSE conducted via telerehabilitation can provide valid and reliable outcomes comparable to clinical decisions made in the FTF environment.

  8. On Conducting Construct Validity Meta-Analyses for the Rorschach: A Reply to Tibon Czopp and Zeligman (2016).

    PubMed

    Mihura, Joni L; Meyer, Gregory J; Dumitrascu, Nicolae; Bombel, George

    2016-01-01

    We respond to Tibon Czopp and Zeligman's (2016) critique of our systematic reviews and meta-analyses of 65 Rorschach Comprehensive System (CS) variables published in Psychological Bulletin (2013). The authors endorsed our supportive findings but critiqued the same methodology when used for the 13 unsupported variables. Unfortunately, their commentary was based on significant misunderstandings of our meta-analytic method and results, such as thinking we used introspectively assessed criteria in classifying levels of support and reporting only a subset of our externally assessed criteria. We systematically address their arguments that our construct label and criterion variable choices were inaccurate and, therefore, meta-analytic validity for these 13 CS variables was artificially low. For example, the authors created new construct labels for these variables that they called "the customary CS interpretation," but did not describe their methodology nor provide evidence that their labels would result in better validity than ours. They cite studies they believe we should have included; we explain how these studies did not fit our inclusion criteria and that including them would have actually reduced the relevant CS variables' meta-analytic validity. Ultimately, criticisms alone cannot change meta-analytic support from negative to positive; Tibon Czopp and Zeligman would need to conduct their own construct validity meta-analyses. PMID:27153466

  9. Copper Conductivity Model Development and Validation Using Flyer Plate Experiments on the Z-machine

    NASA Astrophysics Data System (ADS)

    Riford, L.; Lemke, R. W.; Cochrane, K.

    2015-11-01

    Magnetically accelerated flyer plate experiments done on Sandia's Z-machine provide insight into a multitude of materials problems at high energies and densities including conductivity model development and validation. In an experiment with ten Cu flyer plates of thicknesses 500-1000 μm, VISAR measurements exhibit a characteristic jump in the velocity correlated with magnetic field burn-through and the expansion of melted material at the free surface. The experiment is modeled using Sandia's shock and multiphysics MHD code ALEGRA. Simulated free surface velocities are within 1% of the measured data early in time, but divergence occurs at the feature, where the simulation indicates a slower burn through time. The cause was found to be in the Cu conductivity model's compressed regime. The model was improved by lowering the conductivity in the region 12.5-16 g/cc and 350-16000 K with a novel parameter based optimization method using the velocity feature as a figure of merit. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U. S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. The validation of the robust input estimation approach to two-dimensional inverse heat conduction problems

    SciTech Connect

    Tuan, P.C.; Ju, M.C.

    2000-03-01

    A novel adaptive and robust input estimation inverse methodology of estimating the time-varying unknown heat flux, named as the input, on the two active boundaries of a 2-D inverse heat conduction problem is presented. The algorithm includes using the Kalman filter to propose a regression model between the residual innovation and the two thermal unknown boundaries flux through given 2-D heat conduction state-space models and noisy measurement sequence. Based on this regression equation, a recursive least-square estimator (RLSE) weighted by the forgetting factor is proposed to on-line estimate these unknowns. The adaptive and robust weighting technique is essential since unknowns input are time-varied and have unpredictable changing status. In this article, the authors provide the bandwidth analysis together with bias and variance tests to construct an efficient and robust forgetting factor as the ratio between the standard deviation of measurement and observable bias innovation at each time step. Herein, the unknowns are robustly and adaptively estimated under the system involving measurement noise, process error, and unpredictable change status of time-varying unknowns. The capabilities of the proposed algorithm are demonstrated through the comparison with the conventional input estimation algorithm and validated by two benchmark performance tests in 2-D cases. Results show that the proposed algorithm not only exhibits superior robust capability but also enhances the estimation performance and highly facilitates practical implementation.

  15. 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.

  16. Lessons learned in the conduct, validation, and interpretation of national population based HIV surveys.

    PubMed

    Calleja, Jesús M García; Marum, Lawrence H; Cárcamo, César P; Kaetano, Lovemore; Muttunga, James; Way, Ann

    2005-05-01

    In the past few years several countries have conducted national population-based HIV surveys. Survey methods, levels of participation bias from absence or refusal and lessons learned conducting such surveys are compared in four national population surveys: Mali, Kenya, Peru and Zambia. In Mali, Zambia, and Kenya, HIV testing of adult women and men was included in the national-level demographic and health surveys carried out regularly in these countries, whereas in Peru the national HIV survey targeted young people in 24 cities with populations over 50 000.The household response rate was above 90% in all countries, but some individuals were absent for interviews. HIV testing rates were between 70 and 79% of those eligible, with higher test rates for women. Three critical questions in this type of survey need to be answered: who did the surveys miss; how much it matters that they were missed; and what can be done to increase the participation of respondents so the coverage rates are adequate. The level of representativeness of the populations tested was adequate in each survey to provide a reliable national estimate of HIV prevalence that complements other methods of HIV surveillance. Different lessons were learned from each survey. These population-based HIV seroprevalence surveys demonstrate that reliable and useful results can be obtained, although they require careful planning and increased financial and human resource investment to maximize responses at the household and individual level, which are key elements to validate survey results.This review was initiated through an international meeting on 'New strategies for HIV/AIDS Surveillance in Resource-constrained Countries' held in Addis Ababa on 26-30 January 2004 to share and develop recommendations to guide future surveys. PMID:15930844

  17. 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…

  18. 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…

  19. Structural and Electrical Study of Conducting Polymers

    NASA Astrophysics Data System (ADS)

    Shaktawat, Vinodini; Dixit, Manasvi; Saxena, N. S.; Sharma, Kananbala

    2010-06-01

    Pure and oxalic acid doped conducting polymers (polyaniline and polypyrrole) were chemically synthesized using ammonium persulfate (APS) as an oxidant. These samples were characterized through Scanning Electron Microscopy (SEM), which provides information about the surface topography of polymers. I-V characteristics have been recorded at room temperature as well as in the temperature range from 313 K to 463 K. So obtained characteristic curves were found to be linear. Temperature dependence of conductivity suggests a semiconducting nature in polyaniline samples with increase in temperature, whereas oxalic acid doped polypyrrole sample suggests a transition from semiconducting to metallic nature with the increase of temperature.

  20. 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

  1. Validation study of Polar V800 accelerometer

    PubMed Central

    Hernández-Vicente, Adrián; De Cocker, Katrien; Garatachea, Nuria

    2016-01-01

    Background The correct quantification of physical activity (PA) and energy expenditure (EE) in daily life is an important target for researchers and professionals. The objective of this paper is to study the validity of the Polar V800 for the quantification of PA and the estimation of EE against the ActiGraph (ActiTrainer) in healthy young adults. Methods Eighteen Caucasian active people (50% women) aged between 19–23 years wore an ActiTrainer on the right hip and a Polar V800 on the preferred wrist during 7 days. Paired samples t-tests were used to analyze differences in outcomes between devices, and Pearson’s correlation coefficients to examine the correlation between outcomes. The agreement was studied using the Bland-Altman method. Also, the association between the difference and the magnitude of the measurement (heteroscedasticity) was examined. Sensitivity, specificity and area under the receiver operating characteristic curve (ROC-AUC value) were calculated to evaluate the ability of the devices to accurately define a person who fulfills the recommendation of 10,000 daily steps. Results The devices significantly differed from each other on all outcomes (P<0.05), except for Polar V800’s alerts vs. ActiTrainer’s 1 hour sedentary bouts (P=0.595) and Polar V800’s walking time vs. ActiTrainer’s lifestyle time (P=0.484). Heteroscedasticity analyses were significant for all outcomes, except for Kcal and sitting time. The ROC-AUC value was fair (0.781±0.048) and the sensitivity and specificity was 98% and 58%, respectively. Conclusions The Polar V800 accelerometer has a comparable validity to the accelerometer in free-living conditions, regarding “1 hour sedentary bouts” and “V800’s walking time vs. ActiTrainer’s lifestyle time” in young adults. PMID:27570772

  2. 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.

  3. 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.

  4. 40 CFR 761.395 - A validation study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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 30 2010-07-01 2010-07-01 false A validation study. 761.395...

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

    ERIC Educational Resources Information Center

    Perepletchikova, Francheska; Kazdin, Alan E.

    2004-01-01

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

  6. Validation studies of a computational model for molten material freezing

    SciTech Connect

    Sawada, Tetsuo; Ninokata, Hisashi; Shimizu, Akinao

    1996-02-01

    Validation studies are described of a computational model for the freezing of molten core materials under core disruptive accident conditions of fast breeder reactors. A series of out-of-pile experiments named SIMBATH, performed at Forschungszentrum Karlsruhe in Germany, has already been analyzed with the SIMMER-II code. In the current study, TRAN simulation tests in the SIMBATH facility are analyzed by SIMMER-II for its modeling validation of molten material freezing. The original TRAN experiments were performed at Sandia National laboratories to examine the freezing behavior of molten UO{sub 2} injected into an annular channels. In the TAN simulation experiments of the SIMBATH series, similar freezing phenomena are investigated for molten thermite, a mixture of Al{sub 2}O{sub 3} and iron, instead of UO{sub 2}. Two typical TRAN simulation tests are analyzed that aim at clarification of the applicability of the code to the freezing process during the experiments. The distribution of molten materials that are deposited in the test section according to the experimental measurements and in calculations by SIMMER-II is compared. These studies confirm that the conduction-limited freezing model combined with the rudimentary bulk freezing (particle-jamming) model of SIMMER-II is compared. These studies confirm that the conduction-limited freezing model combined with the rudimentary bulk freezing (particle-jamming) model of SIMMER-II could be used to reproduce the TRAN simulation experiments satisfactorily. This finding encourages the extrapolation of the results of previous validation research for SIMMER-II based on other SIMBATH tests to reactor case analyses. The calculation by SIMMER-II suggest that further improvements of the model, such as freezing on a convex surface of pin cladding and the scraping of crusts, make possible more accurate simulation of freezing phenomena.

  7. 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…

  8. 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

  9. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The...

  10. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The...

  11. 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... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The...

  12. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The...

  13. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The...

  14. 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.

  15. Identification of Learning Disabilities in Ontario: A Validity Study.

    ERIC Educational Resources Information Center

    MacIntyre, Robert B.; And Others

    The study examined the process by which diagnostic data on children thought to have learning disabilities (LD) are generated and used. Emphasis was placed on the validity of test instruments in common use in the field. Since part of the practical validity of any instrument used to identify an LD child rests on the validity of the LD construct…

  16. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Conduct of a study. 160.130 Section 160.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The...

  17. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Conduct of a study. 160.130 Section 160.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The...

  18. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Conduct of a study. 160.130 Section 160.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The...

  19. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Conduct of a study. 160.130 Section 160.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The...

  20. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Conduct of a study. 160.130 Section 160.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The...

  1. 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. PMID:27092194

  2. Summary of Validity Data from the Admissions Testing Program Validity Study Service.

    ERIC Educational Resources Information Center

    Ford, Susan F.; Campos, Sandy

    Validity data (prediction of first-year grade point average) for colleges participating in the Admissions Testing Program Validity Study Service (VSS) and based on students entering college in 1964 through 1974 are summarized for the following predictors: Scholastic Aptitude Test (SAT)--verbal score, SAT--mathematical score, high school record,…

  3. College of the Canyons Predictive Validity Studies.

    ERIC Educational Resources Information Center

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

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

  4. Conductivity and electrical studies of plasticized carboxymethyl cellulose based proton conducting solid biopolymer electrolytes

    NASA Astrophysics Data System (ADS)

    Isa, M. I. N.; Noor, N. A. M.

    2015-12-01

    In this paper, a proton conducting solid biopolymer electrolytes (SBE) comprises of carboxymethyl cellulose (CMC) as polymer host, ammonium thiocyanate (NH4SCN) as doping salt and ethylene carbonate (EC) as plasticizer has been prepared via solution casting technique. Electrical Impedance Spectroscopy (EIS) was carried out to study the conductivity and electrical properties of plasticized CMC-NH4SCN SBE system over a wide range of frequency between 50 Hz and 1 MHz at temperature range of 303 to 353 K. Upon addition of plasticizer into CMC-NH4SCN SBE system, the conductivity increased from 10-5 to 10-2 Scm-1. The highest conductivity was obtained by the electrolyte containing 10 wt.% of EC. The conductivity of plasticized CMC-NH4SCN SBE system by various temperatures obeyed Arrhenius law where the ionic conductivity increased as the temperature increased. The activation energy, Ea was found to decrease with enhancement of EC concentration. Dielectric studies for the highest conductivity electrolyte obeyed non-Debye behavior. The conduction mechanism for the highest conductivity electrolyte was determined by employing Jonsher's universal power law and thus, can be represented by the quantum mechanical tunneling (QMT) model.

  5. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Conduct of a study. 792.130 Section 792.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of...

  6. 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.

  7. 29 CFR 1607.14 - Technical standards for validity studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... with these guidelines. See sections 6 and 7 above. A. Validity studies should be based on review of information about the job. Any validity study should be based upon a review of information about the job for which the selection procedure is to be used. The review should include a job analysis except as...

  8. 40 CFR 761.395 - A validation study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false A validation study. 761.395 Section 761.395 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL... PROHIBITIONS Comparison Study for Validating a New Performance-Based Decontamination Solvent Under §...

  9. 40 CFR 761.395 - A validation study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false A validation study. 761.395 Section 761.395 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL... PROHIBITIONS Comparison Study for Validating a New Performance-Based Decontamination Solvent Under §...

  10. 40 CFR 761.395 - A validation study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false A validation study. 761.395 Section 761.395 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL... PROHIBITIONS Comparison Study for Validating a New Performance-Based Decontamination Solvent Under §...

  11. 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..., AND USE PROHIBITIONS Comparison Study for Validating a New Performance-Based Decontamination...

  12. 40 CFR 761.395 - A validation study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false A validation study. 761.395 Section 761.395 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL... PROHIBITIONS Comparison Study for Validating a New Performance-Based Decontamination Solvent Under §...

  13. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Conduct of a study. 792.130 Section 792.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study §...

  14. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 33 2012-07-01 2012-07-01 false Conduct of a study. 792.130 Section 792.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study §...

  15. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 32 2014-07-01 2014-07-01 false Conduct of a study. 792.130 Section 792.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study §...

  16. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 33 2013-07-01 2013-07-01 false Conduct of a study. 792.130 Section 792.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study §...

  17. 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. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  18. 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. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  19. 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. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  20. 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. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

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

    ERIC Educational Resources Information Center

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

    2006-01-01

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

  2. A Validity Study of the Pain Apperception Test

    ERIC Educational Resources Information Center

    Haase, Richard F.; And Others

    1975-01-01

    This study assessed the validity of the Pain Apperception Test (PAT) against an accepted and validated predictive measure of pain tolerance, a Kinesthetic After Effects Task (KAE). As well, it replicated an earlier finding by Petrovich that suggested that scores derived from the PAT are related significantly to neuroticism. (Author/RK)

  3. 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.…

  4. The Graduate Record Examinations Validity Study Service: Yesterday and Tomorrow.

    ERIC Educational Resources Information Center

    Kingston, Neal M.; And Others

    The Graduate Record Examinations (GRE) Validity Study Service (VSS) was developed by the Educational Testing Service at the request of the GRE Board to help graduate departments investigate the validity of their student selection procedures. The GRE VSS reports are aimed primarily at graduate department chairpersons and faculty members--those who…

  5. FEM Simulation and Experimental Validation of LBW Under Conduction Regime of Ti6Al4V Alloy

    NASA Astrophysics Data System (ADS)

    Churiaque, C.; Amaya-Vazquez, M. R.; Botana, F. J.; Sánchez-Amaya, J. M.

    2016-08-01

    Laser Beam Welding (LBW) is an advanced process to join materials with a laser beam of high energy density. LBW is especially suitable to join titanium alloys, as it allows high localization and low size of the melting pool, reducing considerably the energy of the process, in comparison with other welding technologies. Among the two widely known welding regimes, conduction and keyhole, the former is claimed to be a viable alternative to keyhole, mainly because it is a very stable process, provides high-quality welds free of defects, and involves lower laser cost. In the present work, a Finite Element Method (FEM) has been developed to simulate the LBW of Ti6Al4V alloy under conduction regime. The "Goldak double ellipsoid model" has been taken for the first time to simulate this LBW conduction process. In order to refine and validate the model, experimental conduction welding tests were performed on Ti6Al4V pieces with a high-power diode laser. Microstructural analyses and hardness measurements were also performed on the laser weld beads to identify the generated phases. Distortion and residual stresses were also obtained from the FEM simulations. An excellent agreement between the simulation and experimental results was found regarding the bead morphology and phase transformations.

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

    PubMed

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

    2009-12-01

    The earthworm (Lumbricus terrestris) is presented as an in vitro model of a peripheral nerve containing only two fibers each with distinctly different conduction velocities, the median and lateral giant fibers (MGF and LGF). The worm model is used with a multi-contact cuff electrode to validate the spatial-temporal filtering effect of different electrode contact configurations and the effect of applying a delay adder and matched filter tuned to either the MGF or LGF action potential (AP) to extract conduction direction and velocity from the recording. The results confirmed the known effect of inter-electrode spacing and bipolar and tripolar recording configuration on the AP amplitude. It also demonstrates a crossover point where the amplitude of the tripolar recording is larger than the monopolar recording, an effect of the slower action potential conduction velocities in the worm. The delay adder was found to be an effective velocity sensitive filter, able to discriminate units based on conduction velocity. The matched filter to be an effective means to eliminate artifact and increase signal to noise ratios, however was not found to improve selectivity. PMID:19762269

  7. FEM Simulation and Experimental Validation of LBW Under Conduction Regime of Ti6Al4V Alloy

    NASA Astrophysics Data System (ADS)

    Churiaque, C.; Amaya-Vazquez, M. R.; Botana, F. J.; Sánchez-Amaya, J. M.

    2016-07-01

    Laser Beam Welding (LBW) is an advanced process to join materials with a laser beam of high energy density. LBW is especially suitable to join titanium alloys, as it allows high localization and low size of the melting pool, reducing considerably the energy of the process, in comparison with other welding technologies. Among the two widely known welding regimes, conduction and keyhole, the former is claimed to be a viable alternative to keyhole, mainly because it is a very stable process, provides high-quality welds free of defects, and involves lower laser cost. In the present work, a Finite Element Method (FEM) has been developed to simulate the LBW of Ti6Al4V alloy under conduction regime. The "Goldak double ellipsoid model" has been taken for the first time to simulate this LBW conduction process. In order to refine and validate the model, experimental conduction welding tests were performed on Ti6Al4V pieces with a high-power diode laser. Microstructural analyses and hardness measurements were also performed on the laser weld beads to identify the generated phases. Distortion and residual stresses were also obtained from the FEM simulations. An excellent agreement between the simulation and experimental results was found regarding the bead morphology and phase transformations.

  8. 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…

  9. 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.

  10. 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.

  11. Experimental validations of in vivo human musculoskeletal tissue conductivity images using MR-based electrical impedance tomography.

    PubMed

    Jeong, Woo Chul; Meng, Zi Jun; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

    2014-07-01

    Magnetic resonance (MR)-based electrical impedance tomography (MREIT) is a widely used imaging technique that provides high-resolution conductivity images at DC or below the 1 kHz frequency range. Using an MR scanner, this technique injects imaging currents into the human body and measures induced internal magnetic flux density data. By applying the recent progress of MREIT techniques, such as chemical shift artifact correction, multi-echo pulse sequence, and improved reconstruction algorithm, we can successfully reconstruct conductivity images of the human body. Meanwhile, numerous studies reported that the electrical conductivity of human tissues could be inferred from in vitro or ex vivo measurements of different species. However, in vivo tissues may differ from in vitro and/or ex vivo state due to the complicated tissue responses in living organs. In this study, we performed in vivo MREIT imaging of a human lower extremity and compared the resulting conductivity images with ex vivo biological tissue phantom images. The human conductivity images showed unique contrast between two different types of bones, muscles, subcutaneous adipose tissues, and conductive body fluids. Except for muscles and adipose tissues, the human conductivity images showed a similar pattern when compared with phantom results due to the anisotropic characteristic of muscle and the high conductive fluids in the adipose tissue.

  12. 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.

  13. Validity of the Study Practices Inventory for Pharmacy Students.

    ERIC Educational Resources Information Center

    Willoughby, T. Lee; And Others

    1979-01-01

    The validity of the Study Practices Inventory (SPI) for a group of entering pharmacy students was assessed. The four subscores of the SPI showed moderate correlation with entering grade point average and with measures of reading ability. (Author/JKS)

  14. 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.

  15. 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.

  16. Identifying Primary Spontaneous Pneumothorax from Administrative Databases: A Validation Study

    PubMed Central

    Frechette, Eric; Guidolin, Keegan; Seyam, Ayman; Choi, Yun-Hee; Jones, Sarah; McClure, J. Andrew; Winick-Ng, Jennifer; Welk, Blayne; Malthaner, Richard A.

    2016-01-01

    Introduction. Primary spontaneous pneumothorax (PSP) is a disorder commonly encountered in healthy young individuals. There is no differentiation between PSP and secondary pneumothorax (SP) in the current version of the International Classification of Diseases (ICD-10). This complicates the conduct of epidemiological studies on the subject. Objective. To validate the accuracy of an algorithm that identifies cases of PSP from administrative databases. Methods. The charts of 150 patients who consulted the emergency room (ER) with a recorded main diagnosis of pneumothorax were reviewed to define the type of pneumothorax that occurred. The corresponding hospital administrative data collected during previous hospitalizations and ER visits were processed through the proposed algorithm. The results were compared over two different age groups. Results. There were 144 cases of pneumothorax correctly coded (96%). The results obtained from the PSP algorithm demonstrated a significantly higher sensitivity (97% versus 81%, p = 0.038) and positive predictive value (87% versus 46%, p < 0.001) in patients under 40 years of age than in older patients. Conclusions. The proposed algorithm is adequate to identify cases of PSP from administrative databases in the age group classically associated with the disease. This makes possible its utilization in large population-based studies. PMID:27445518

  17. 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.

  18. 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.

  19. Value-Eroding Teacher Behaviors Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Arseven, Zeynep; Kiliç, Abdurrahman; Sahin, Seyma

    2016-01-01

    In the present study, it is aimed to develop a valid and reliable scale for determining value-eroding behaviors of teachers, hence their values of judgment. The items of the "Value-eroding Teacher Behaviors Scale" were designed in the form of 5-point likert type rating scale. The exploratory factor analysis (EFA) was conducted to…

  20. 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…

  1. 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.

  2. 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.

  3. 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…

  4. 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.

  5. The Validity and Precision of the Comparative Interrupted Time-Series Design: Three Within-Study Comparisons

    ERIC Educational Resources Information Center

    St. Clair, Travis; Hallberg, Kelly; Cook, Thomas D.

    2016-01-01

    We explore the conditions under which short, comparative interrupted time-series (CITS) designs represent valid alternatives to randomized experiments in educational evaluations. To do so, we conduct three within-study comparisons, each of which uses a unique data set to test the validity of the CITS design by comparing its causal estimates to…

  6. 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.

  7. 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…

  8. 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…

  9. Validity in Action: Lessons from Studies of Data Use

    ERIC Educational Resources Information Center

    Moss, Pamela A.

    2013-01-01

    Studies of data use illuminate ways in which education professionals have used test scores and other evidence relevant to students' learning--in action in their own contexts of work--to make decisions about their practice. These studies raise instructive challenges for a validity theory that focuses on intended interpretations and uses of test…

  10. Imagery Measures of Ego, Id, Superego, and Identity: Validity Studies.

    ERIC Educational Resources Information Center

    Cartwright, D.; DeBruin, J.

    1988-01-01

    Five validity studies of the id, ego, superego, and identity scales of the Study of Imagery are reported, using undergraduate students. Multistage Bonferroni procedures are used to evaluate the significance of results. The scales are related to each other and to toughmindedness, self-control, and behavioral conflict. (TJH)

  11. 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

  12. 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…

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Greek version of the Internet Addiction Test: a validation study.

    PubMed

    Tsimtsiou, Zoi; Haidich, Anna-Bettina; Kokkali, Stamatia; Dardavesis, Theodoros; Young, Kimberly S; Arvanitidou, Malamatenia

    2014-06-01

    The aim of this project was to translate, culturally adapt and validate the Internet Addiction Test (IAT) in Greek adults. Twenty-one post-graduate medical students participated in the cultural adaptation procedure and 151 both post- and under-graduate medical students in the validation process. The internal consistency shown by a Cronbach's alpha was 0.91. Two-week test-retest reliability was rtt = 0.84, p < 0.001. Face validity was affirmed by 83.6 % of the students. In terms of convergent validity, the hours of daily internet use were positively correlated with IAT score (rho = 0.48, p < 0.001). Moreover, IAT scores were higher in students that reported use of online gambling (40.5 vs 29.2, p = 0.004), pornographic sites (36.5 vs 28.0, p = 0.003) and online games (35.6 vs 28.2, p = 0.009). Exploratory factor analysis revealed three interpretable factors for the IAT, "Psychological/Emotional Conflict", "Time Management" and "Neglect Work", that showed good internal consistency and concurrent validity, explaining 55.3 % of the variance. The Greek version of IAT has shown good psychometric properties, comparable with the original IAT and the previously published translated versions, and can be a useful tool in future studies on internet addiction.

  18. Greek version of the Internet Addiction Test: a validation study.

    PubMed

    Tsimtsiou, Zoi; Haidich, Anna-Bettina; Kokkali, Stamatia; Dardavesis, Theodoros; Young, Kimberly S; Arvanitidou, Malamatenia

    2014-06-01

    The aim of this project was to translate, culturally adapt and validate the Internet Addiction Test (IAT) in Greek adults. Twenty-one post-graduate medical students participated in the cultural adaptation procedure and 151 both post- and under-graduate medical students in the validation process. The internal consistency shown by a Cronbach's alpha was 0.91. Two-week test-retest reliability was rtt = 0.84, p < 0.001. Face validity was affirmed by 83.6 % of the students. In terms of convergent validity, the hours of daily internet use were positively correlated with IAT score (rho = 0.48, p < 0.001). Moreover, IAT scores were higher in students that reported use of online gambling (40.5 vs 29.2, p = 0.004), pornographic sites (36.5 vs 28.0, p = 0.003) and online games (35.6 vs 28.2, p = 0.009). Exploratory factor analysis revealed three interpretable factors for the IAT, "Psychological/Emotional Conflict", "Time Management" and "Neglect Work", that showed good internal consistency and concurrent validity, explaining 55.3 % of the variance. The Greek version of IAT has shown good psychometric properties, comparable with the original IAT and the previously published translated versions, and can be a useful tool in future studies on internet addiction. PMID:24307176

  19. The RCRAS and legal insanity: a cross-validation study.

    PubMed

    Rogers, R; Seman, W; Wasyliw, O E

    1983-07-01

    Examined the RCRAS as an empirically based approach to insanity evaluations. Previous research has been encouraging with regard to the RCRAS' interrater reliability and construct validity. The present study, with a larger data base (N = 111), sought to cross-validate these findings. Results from five forensic centers established satisfactory reliability for the RCRAS (mean kappa r = .80 for decision variables for criminal responsibility) and differentiating patterns for four of the five scales between sane and insane patient-defendants. Results further suggested that the RCRAS was generalizable across age, sex, criminal behavior, and location of the forensic evaluation. These findings were discussed with respect to the potential clinical utility of the RCRAS.

  20. 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

  1. A Cross-Validation Study of the Posttraumatic Growth Inventory

    ERIC Educational Resources Information Center

    Sheikh, Alia I.; Marotta, Sylvia A.

    2005-01-01

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

  2. 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…

  3. 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…

  4. 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…

  5. Assessing Meritorious Teacher Performance: A Differential Validity Study.

    ERIC Educational Resources Information Center

    Ellett, Chad D; Capie, William

    The Teacher Assessment and Development System (TADS) - Meritorious Teacher Program (MTP) FORM instrument is used in the Dade County Public Schools, Miami, Florida, to evaluate teachers. Its validity for decisions concerning merit pay for master teachers was examined in this study. Specifically, its ability to discriminate between high performing…

  6. 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,…

  7. 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…

  8. 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…

  9. 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…

  10. 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,…

  11. 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…

  12. 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.

  13. Meteorological conditions during the winter validation study at Rocky Flats, Colorado: An overview

    SciTech Connect

    Hodgin, C.R.

    1991-11-06

    The objective for the Winter Validation Study was to gather field data for validation of the Terrain-Responsive Atmospheric Code (TRAC) under winter time meteorological conditions. Twelve tracer tests were conducted during a two-week period in February 1991. Each test lasted 12 hours, with releases of SF{sub 6} tracer from the Rocky Flats Plant near Golden, Colorado. The tests included ground-based and airborne sampling to 16 km from the release point. This presentation summarizes meteorological conditions during the testing period. Forty six viewgraphs are included.

  14. Validity of repeated dietary measurements in a dietary intervention study.

    PubMed

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

    1992-10-01

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

  15. 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

  16. Reliable Digit Span: a systematic review and cross-validation study.

    PubMed

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

    2012-03-01

    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 limitations, thus increasing the measure's clinical utility. Sensitivity and specificity rates were calculated for the ≤6 and ≤7 cutoffs when data were globally combined and divided by clinical groups. The cross-validation of specific diagnostic groups was consistent with the data reported in the literature. Overall, caution should be used when utilizing the ≤7 cutoff in all clinical groups and when utilizing the ≤6 cutoff in the following groups: cerebrovascular accident, severe memory disorders, mental retardation, borderline intellectual functioning, and English as a second language. Additional limitations and cautions are provided.

  17. Studies on conducting polymer and conducting polymerinorganic composite electrodes prepared via a new cathodic polymerization method

    NASA Astrophysics Data System (ADS)

    Singh, Nikhilendra

    A novel approach for the electrodeposition of conducting polymers and conducting polymer-inorganic composite materials is presented. The approach shows that conducting polymers, such as polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT) can be electrodeposited by the application of a cathodic bias that generates an oxidizing agent, NO+, via the in-situ reduction of nitrate anions. This new cathodic polymerization method allows for the deposition of PPy and PEDOT as three dimensional, porous films composed of spherical polymer particles. The method is also suitable for the co-deposition of inorganic species producing conducting polymer-inorganic composite electrodes. Such composites are used as high surface area electrodes in Li-ion batteries, electrochemical hydrogen evolution and in the development of various other conducting polymer-inorganic composite electrodes. New Sn-PPy and Sb-PPy composite electrodes where Sn and Sb nanoparticles are well dispersed among the PPy framework are reported. These structures allow for decreased stress during expansion and contraction of the active material (Sn, Sb) during the alloying and de-alloying processes of a Li-ion battery anode, significantly alleviating the loss of active material due to pulverization processes. The new electrochemical synthesis mechanism allows for the fabrication of Sn-PPy and Sb-PPy composite electrodes directly from a conducting substrate and eliminates the use of binding materials and conducting carbon used in modern battery anodes, which significantly simplifies their fabrication procedures. Platinum (Pt) has long been identified as the most efficient catalyst for electrochemical water splitting, while nickel (Ni) is a cheaper, though less efficient alternative to Pt. A new morphology of PPy attained via the aforementioned cathodic deposition method allows for the use of minimal quantities of Pt and Ni dispersed over a very high surface area PPy substrate. These composite electrodes

  18. Viscoelastic study of conducting polymers using quartz crystal microbalance

    NASA Astrophysics Data System (ADS)

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

    2006-03-01

    Application of conducting polymers has been growing widely in different fields such as batteries, solar cells, capacitors and actuators. Mechanical properties of conducting polymers like flexibility, high power to mass ratio and high active strain make them potentially applicable to robotic and automation industries. Obviously, a dynamic model of the actuation phenomenon in conducting polymers is needed to study its controllability and also to optimize the mechanical performance. De Rossi and colleagues suggest treating the mechanical behaviour of conducting polymers separately from the viscoelastic structural model and electrochemical actuation [1]. But it has been observed that the effects of electrochemical actuation and diffusion of ions on the viscoelastic coefficients cannot be neglected in some conducting polymer actuators, as shown in [1]. In this paper, we present the effects of cyclic voltammetry actuation on shear modulus of polypyrrole in propylene carbonate and EMI.TSFI as measured by an electrochemical Quartz Crystal Microbalance (eQCM). The QCM consists basically of an AT-cut piezoelectric quartz crystal disc with metallic electrode films deposited on its faces. One face is exposed to the active medium. A driver circuit applies an AC signal to the electrodes, causing the crystal to oscillate in a shear mode, at a given resonance frequency. QCM has been routinely used for the determination of mass changes. Measured resonance frequency shifts are converted into mass changes by the wellknown Sauerbrey's equation. In this paper, we correlate the admittance output of QCM to the real shear modulus of polypyrrole. Then the results of the correlation which contains mechanical data are presented during actuation using two different types of electrolyte.

  19. Studies of Electronic Conduction in Some Small Gallium Arsenic Based.

    NASA Astrophysics Data System (ADS)

    Whittington, Geoffrey

    Available from UMI in association with The British Library. Requires signed TDF. This thesis describes experimental investigations of the physics involved with low temperature electronic conduction in three different semiconductor systems. The research relies upon technological advances in fabrication of such semiconductor samples. The first work deals with the effects of quantum interference of electrons in some submicron size, heavily doped Gallium Arsenide wire samples. The interesting effect of aperiodic fluctuations in the magnetoresistance of these samples is studied, making use of recently formulated theory on the subject, and with experimental data taken over the magnetic field range 0 to 10 tesla. The results verify the connection between the mean amplitude of the fluctuations and the field correlation period, in terms of the correlation function introduced in the theory. The second work is on the impurity-assisted tunnelling conduction in a magnetic field of three thin rm n^{+}/n^{-}/n^ {+} GaAs sandwich layer structures. The conduction of the system is shown to be determined by impurities lying in the centre of the middle layer. This allows the connection to be made between the conductivity of the system in a magnetic field, and the field-dependent shape of the donor electron wavefunction. The relative variation in resistance with angle to an applied magnetic field was measured, and is shown to be in agreement with predictions based on calculations of the shape of a normalised hydrogenic state wavefunction in high magnetic fields. The third work concerns the tunnelling conduction of a symmetrical GaAs/(AlGa)As/GaAs hetero-barrier system. The current-voltage characteristics at low temperature are fully modelled for applied voltages up to 180mV, using conventional theory of tunnelling and a position-dependent effective mass in the barrier. Low current oscillations in the Fowler-Nordheim tunnelling regime, corresponding to quantum reflection at the

  20. Validity of the Convergence Insufficiency Symptom Survey: A Confirmatory Study

    PubMed Central

    2009-01-01

    Purpose The objectives of the present study were to evaluate whether investigator bias influenced the Convergence Insufficiency Symptom Survey (CISS) scores of children with normal binocular vision (NBV) in our original validation study, reevaluate the usefulness of the cut-off score of 16, and reexamine the validity of the CISS. Methods Six clinical sites participating in the Convergence Insufficiency Treatment Trial (CITT) enrolled 46 children 9 - <18 years with NBV. Examiners masked to the child’s binocular vision status administered the CISS. The mean CISS score was compared to that from the children with NBV in the original, unmasked CISS study and also to that of the 221 symptomatic CI children enrolled in the CITT. Results The mean (±SD) CISS score for 46 subjects with NBV was 10.4 (±8.1). This was comparable to that from our prior unmasked NBV study (mean = 8.1(± 6.2); p = 0.11), but was significantly different from that of the CITT CI group (mean = 29.8 ± 9.0; p < 0.001). Eighty-three percent of these NBV subjects scored less than 16 on the CISS, which is not statistically different from the 87.5% found in the original unmasked study (p = 0.49). Conclusions Examiner bias did not affect the CISS scores for subjects with NBV in our prior study. The CISS continues to be a valid instrument for quantifying symptoms in 9 to <18 year-old children and these results confirm the validity of a cut-point of ≥ 16 in distinguishing children with symptomatic CI from those with NBV. PMID:19289977

  1. 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.

  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. A multisite validity study of self-reported anesthesia outcomes.

    PubMed

    Walker, Peter; Pekmezaris, Renee; Lesser, Martin L; Nouryan, Christian N; Rosinia, Frank; Pratt, Kathy; LaVopa, Catherine

    2012-01-01

    The purpose of this study was to assess the validity of a multisite anesthesia voluntary adverse event reporting process. A data validation methodology was used through medical chart review on live records at 3 facilities (N = 600). The per-item aggregated error rate among all 42 data items was 0.3%: 0.1% for quality indicators, 1.3% for demographic/status variables, and 1.7% for administrative items. The per-patient error rate among all 42 data items was 6.3%: 3.0% for quality indicators, 1.7% for demographic/status variables, and 3.0% for administrative items. Trends such as better accuracy for more serious events continue, but observed error rates were lower than those found in previous surveys-an indication that, while further study is needed, nonpunitive voluntary reporting may reduce errors in anesthesia care. PMID:22326979

  4. Transport studies of conducting, semiconducting and photoconducting star polymers

    NASA Astrophysics Data System (ADS)

    Ferguson, John Baker

    Star polymers are studied for their transport properties in the highly conducting state doped with NOPF6 and iodine, the undoped semiconducting state and the photoconducting state. Doped star polymers exhibit variable range hopping of charge carriers. Transport dimensionality and conductivity depend intricately on the processing conditions for doping and casting films. The highest conducting diffusion doped film (room temperature conductivity 50 S/cm) exhibits 2-dimensional variable range for all doping levels. Polymers doped in solution, then cast to form films have 1.4 dimensional variable range hopping for the highest conducting samples with 10 S/cm at room temperature. The hopping dimensionality varies as the conductivity decreases. The doped star polymers remain on the insulator side of the insulator metal transition with localized carriers as revealed with Kramer-Kronig analysis. Optical and near infrared absorbance and photoluminescence reveal the core of the star polymers exist in a solid state solution of the arms with similar absorbance and luminescence for both solution and films. The arms retain the optical properties of their linear analogs indicating the core and arms do not interact quantum mechanically to produce a new state. Excitons created by absorption in the wider band gap cores rapidly migrate to the arms. Photoconductive time of flight mobility measurements reveal an almost field independent mobility at room temperature. This is due to a unique cancellation of on diagonal and off diagonal disorder in the Bassler disorder formalism. The cores introduce heterogeneous regions with a net lower mobility predicted by correlated disorder models. Space charge limited current reveals trap densities several orders of magnitude higher than the carrier density. Photovoltaic performance of star polymer and fullerene blend devices with both 20 nm and 100 nm thick layers are investigated. The thin devices have low open circuit voltages due to space charge

  5. Hopping conduction in 3,4-cycloalkylpolypyrrole perchlorates: A model study of conductivity in polymers:

    NASA Astrophysics Data System (ADS)

    Ezquerra, T. A.; Rühe, J.; Wegner, G.

    1988-02-01

    The conductivity of 3,4-cycloalkyl-substituted polypyrrole perchlorates has been analyzed using hopping theory. The localization length of the charge carriers was found to be 0.8 nm, the actual conductivity at constant temperature being exponentially dependent on the minimum distance, R, between adjacent chains. R can be reasonably estimated from molecular models and was systematically varied between 0.38 nm (unsubstituted polypyrrole) and 1.38 nm (decamethylene chain attached in 3,4-position). The conduction is activated in the temperature range 150-300 K, the activation energy varying systematically from 0.012 to 0.066 eV on increasing R from 0.38 to 1.38 nm.

  6. The Relationship between Nerve Conduction Study and Clinical Grading of Carpal Tunnel Syndrome

    PubMed Central

    Cheluvaiah, Janardhan D.; Agadi, Jagadish B.; Nagaraj, Karthik

    2016-01-01

    Introduction Carpal Tunnel Syndrome (CTS) is the most common nerve entrapment. Subjective sensory symptoms are common place in patients with CTS, but sometimes they are not supported by objective findings in the neurological examination. Electrodiagnostic (EDx) studies are a valid and reliable means of confirming the diagnosis. The amplitudes along with the conduction velocities of the sensory nerve action potential and motor nerve action potential reflect the functional state of axons, and are useful parameters and complement the clinical grading in the assessment of severity of CTS. Aim To conduct median nerve sensory and motor conduction studies on patients with carpal tunnel syndrome and correlate the relationship between nerve conduction study parameters and the clinical severity grading. Materials and Methods Based on clinical assessment, the study patients were divided into 03 groups with mild CTS, moderate CTS and severe CTS respectively as per Mackinnson’s classification. Median and ulnar nerve conduction studies were performed on bilateral upper limbs of 50 patients with symptoms of CTS and 50 age and sex matched healthy control subjects. The relationship between the clinical severity grade and various nerve conduction study parameters were correlated. Results In this prospective case control study, 50 patients with symptoms consistent with CTS and 50 age and sex matched healthy control subjects were examined over a 10 month period. A total of 30 patients had unilateral CTS (right upper limb in 19 and left upper limb in 11) and 20 patients had bilateral CTS. Female to male ratio was 3.54 to 1. Age ranged from 25 to 81 years. The mean age at presentation was 49.68±11.7 years. Tingling paresthesias of hand and first three fingers were the most frequent symptoms 48 (98%). Tinel’s and Phalen’s sign were positive in 36 (72%) and 44 (88%) patients respectively. The mean duration of symptoms at presentation was 52.68±99.81 weeks. 16 patients (32%) had

  7. The Relationship between Nerve Conduction Study and Clinical Grading of Carpal Tunnel Syndrome

    PubMed Central

    Cheluvaiah, Janardhan D.; Agadi, Jagadish B.; Nagaraj, Karthik

    2016-01-01

    Introduction Carpal Tunnel Syndrome (CTS) is the most common nerve entrapment. Subjective sensory symptoms are common place in patients with CTS, but sometimes they are not supported by objective findings in the neurological examination. Electrodiagnostic (EDx) studies are a valid and reliable means of confirming the diagnosis. The amplitudes along with the conduction velocities of the sensory nerve action potential and motor nerve action potential reflect the functional state of axons, and are useful parameters and complement the clinical grading in the assessment of severity of CTS. Aim To conduct median nerve sensory and motor conduction studies on patients with carpal tunnel syndrome and correlate the relationship between nerve conduction study parameters and the clinical severity grading. Materials and Methods Based on clinical assessment, the study patients were divided into 03 groups with mild CTS, moderate CTS and severe CTS respectively as per Mackinnson’s classification. Median and ulnar nerve conduction studies were performed on bilateral upper limbs of 50 patients with symptoms of CTS and 50 age and sex matched healthy control subjects. The relationship between the clinical severity grade and various nerve conduction study parameters were correlated. Results In this prospective case control study, 50 patients with symptoms consistent with CTS and 50 age and sex matched healthy control subjects were examined over a 10 month period. A total of 30 patients had unilateral CTS (right upper limb in 19 and left upper limb in 11) and 20 patients had bilateral CTS. Female to male ratio was 3.54 to 1. Age ranged from 25 to 81 years. The mean age at presentation was 49.68±11.7 years. Tingling paresthesias of hand and first three fingers were the most frequent symptoms 48 (98%). Tinel’s and Phalen’s sign were positive in 36 (72%) and 44 (88%) patients respectively. The mean duration of symptoms at presentation was 52.68±99.81 weeks. 16 patients (32%) had

  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. 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.

  11. 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.

  12. Intent inferencing by an intelligent operator's associate - A validation study

    NASA Technical Reports Server (NTRS)

    Jones, Patricia M.

    1988-01-01

    In the supervisory control of a complex, dynamic system, one potential form of aiding for the human operator is a computer-based operator's associate. The design philosophy of the operator's associate is that of 'amplifying' rather than automating human skills. In particular, the associate possesses understanding and control properties. Understanding allows it to infer operator intentions and thus form the basis for context-dependent advice and reminders; control properties allow the human operator to dynamically delegate individual tasks or subfunctions to the associate. This paper focuses on the design, implementation, and validation of the intent inferencing function. Two validation studies are described which empirically demonstrate the viability of the proposed approach to intent inferencing.

  13. Validation of airway resistance models for predicting pressure loss through anatomically realistic conducting airway replicas of adults and children.

    PubMed

    Borojeni, Azadeh A T; Noga, Michelle L; Martin, Andrew R; Finlay, Warren H

    2015-07-16

    This work describes in vitro measurement of the total pressure loss at varying flow rate through anatomically realistic conducting airway replicas of 10 children, 4 to 8 years old, and 5 adults. Experimental results were compared with analytical predictions made using published airway resistance models. For the adult replicas, the model proposed by van Ertbruggen et al. (2005. J. Appl. Physiol. 98, 970-980) most accurately predicted central conducting airway resistance for inspiratory flow rates ranging from 15 to 90 L/min. Models proposed by Pedley et al. (1970. J. Respir. Physiol. 9, 371-386) and by Katz et al. (2011. J. Biomech. 44, 1137-1143) also provided reasonable estimates, but with a tendency to over predict measured pressure loss for both models. For child replicas, the Pedley and Katz models both provided good estimation of measured pressure loss at flow rates representative of resting tidal breathing, but under predicted measured values at high inspiratory flow rate (60 L/min). The van Ertbruggen model, developed based on flow simulations performed in an adult airway model, tended to under predict measured pressure loss through the child replicas across the range of flow rates studied (2 to 60 L/min). These results are intended to provide guidance for selection of analytical pressure loss models for use in predicting airway resistance and ventilation distribution in adults and children.

  14. Conducting Simulation Studies in the R Programming Environment.

    PubMed

    Hallgren, Kevin A

    2013-10-12

    Simulation studies allow researchers to answer specific questions about data analysis, statistical power, and best-practices for obtaining accurate results in empirical research. Despite the benefits that simulation research can provide, many researchers are unfamiliar with available tools for conducting their own simulation studies. The use of simulation studies need not be restricted to researchers with advanced skills in statistics and computer programming, and such methods can be implemented by researchers with a variety of abilities and interests. The present paper provides an introduction to methods used for running simulation studies using the R statistical programming environment and is written for individuals with minimal experience running simulation studies or using R. The paper describes the rationale and benefits of using simulations and introduces R functions relevant for many simulation studies. Three examples illustrate different applications for simulation studies, including (a) the use of simulations to answer a novel question about statistical analysis, (b) the use of simulations to estimate statistical power, and (c) the use of simulations to obtain confidence intervals of parameter estimates through bootstrapping. Results and fully annotated syntax from these examples are provided.

  15. Conducting Simulation Studies in the R Programming Environment

    PubMed Central

    Hallgren, Kevin A.

    2014-01-01

    Simulation studies allow researchers to answer specific questions about data analysis, statistical power, and best-practices for obtaining accurate results in empirical research. Despite the benefits that simulation research can provide, many researchers are unfamiliar with available tools for conducting their own simulation studies. The use of simulation studies need not be restricted to researchers with advanced skills in statistics and computer programming, and such methods can be implemented by researchers with a variety of abilities and interests. The present paper provides an introduction to methods used for running simulation studies using the R statistical programming environment and is written for individuals with minimal experience running simulation studies or using R. The paper describes the rationale and benefits of using simulations and introduces R functions relevant for many simulation studies. Three examples illustrate different applications for simulation studies, including (a) the use of simulations to answer a novel question about statistical analysis, (b) the use of simulations to estimate statistical power, and (c) the use of simulations to obtain confidence intervals of parameter estimates through bootstrapping. Results and fully annotated syntax from these examples are provided. PMID:25067989

  16. MMR vaccine uptake rates: a data validation study.

    PubMed

    Ghebrehewet, S; Falconer, M; McDonald, P; Schlecht, B

    2003-06-01

    As part of our investigation into the decrease in the measles, mumps and rubella (MMR) vaccine uptake rates, we validated MMR vaccination records of all children born between 01/09/1998 and 31/08/1999 in our area (North Cheshire, South Cheshire, and Wirral). A significant number of children had received their MMR vaccine but were not recorded as such by the Child Health Computer System (CHCS). Reported COVER (cover of vaccination evaluated rapidly) data uptake (combined) for North Cheshire, South Cheshire, and Wirral Health Authorities for the period covered by the data validation study was 90.5%, the corrected uptake following the validation was 92.6%, 2.1% higher than the reported coverage. If the coverage data were to continue to form part of the NHS indicators of PCT performance, action by all PCTs to improve accuracy of immunisation data would be highly desirable. Electronic transfer of information from practices to the CHCS and between CHCSs, i.e. across boundaries, could improve data accuracy.

  17. 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

  18. 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.

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

    NASA Astrophysics Data System (ADS)

    Allwine, J.

    2007-12-01

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

  20. Estimating the Prevalence of Treated Epilepsy Using Administrative Health Data and Its Validity: ESSENCE Study

    PubMed Central

    Lee, Seo-Young; Chung, Soo-Eun; Kim, Dong Wook; Eun, So-Hee; Kang, Hoon Chul; Cho, Yong Won; Yi, Sang Do; Kim, Heung Dong

    2016-01-01

    Background and Purpose Few of the epidemiologic studies of epilepsy have utilized well-validated nationwide databases. We estimated the nationwide prevalence of treated epilepsy based on a comprehensive medical payment database along with diagnostic validation. Methods We collected data on patients prescribed of antiepileptic drugs (AEDs) from the Health Insurance Review and Assessment service, which covers the entire population of Korea. To assess the diagnostic validity, a medical records survey was conducted involving 6,774 patients prescribed AEDs from 43 institutions based on regional clusters and referral levels across the country. The prevalence of treated epilepsy was estimated by projecting the diagnostic validity on the number of patients prescribed AEDs. Results The mean positive predictive value (PPV) for epilepsy was 0.810 for those prescribed AEDs with diagnostic codes that indicate epilepsy or seizure (Diagnosis-E), while it was 0.066 for those without Diagnosis-E. The PPV tended to decrease with age in both groups, with lower values seen in females. The prevalence was 3.84 per 1,000, and it was higher among males, children, and the elderly. Conclusions The prevalence of epilepsy in Korea was comparable to that in other East Asian countries. The diagnostic validity of administrative health data varies depending on the method of case ascertainment, age, and sex. The prescriptions of AEDs even without relevant diagnostic codes should be considered as a tracer for epilepsy.

  1. 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

  2. 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.

  3. Comparative study of atrial fibrillation and AV conduction in mammals.

    PubMed

    Meijler, F L; van der Tweel, I

    1987-01-01

    Atrial fibrillation is one of the most common cardiac arrhythmias in humans. It also occurs quite frequently in dogs and horses. Comparative study of this arrhythmia may contribute to better understanding of the pathophysiological mechanisms involved. In this study, we present a quantitative analysis of atrial fibrillation in humans, dogs, horses, and in a kangaroo, making use of histograms and serial autocorrelograms of the ventricular rhythm with and without digitalis medication. Increase in the size of the animal and thus in the size of the heart is accompanied by a decrease in ventricular rate. The ventricular rhythm was random in the dog, kangaroo, and man, but periodicity was present in the horse. Digitalis decreased the ventricular rate in all species studied and enforced the periodicity in the horse. The differences in the atrial excitation process, atrioventricular (AV) conduction, and ventricular behavior between the four species studied are small when compared with the differences in their heart size. We conclude that in evolution, as far as the heart is concerned, cell size and morphology probably prevail over cell-function.

  4. 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.

  5. Validation of holistic nursing competencies: role-delineation study, 2012.

    PubMed

    Erickson, Helen Lorraine; Erickson, Margaret Elizabeth; Campbell, Joan A; Brekke, Mary E; Sandor, M Kay

    2013-12-01

    The American Holistic Nurses Credentialing Corporation (AHNCC), certifying body for nurses practicing within the precepts of holistic nursing, uses a systematic process to guide program development. A previous publication described their early work that distinguished basic and advanced holistic nursing and development of related examinations. A more recent publication described the work of AHNCC from 2004 to 2012, including a role-delineation study (RDS) that was undertaken to identify and validate competencies currently used by holistic nurses. A final report describes the RDS design, methods, and raw data information. This article discusses AHNCC's goals for undertaking the 2012 Holistic Nursing RDS and the implications for the certification programs.

  6. 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.

  7. Low Frequency Eddy Current Benchmark Study for Model Validation

    NASA Astrophysics Data System (ADS)

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

    2011-06-01

    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.

  8. Predicting Marital Success with PREPARE: A Predictive Validity Study.

    ERIC Educational Resources Information Center

    Fowers, Blaine J.; Olson, David H.

    1986-01-01

    Assessed the utility of the premarital inventory, PREPARE, in predicting marital success. Conducted a three-year follow-up study with couples (N=164) who took PREPARE during their engagement. Found that the PREPARE scores from three months before marriage could predict with 80-90% accuracy which couples were separated and divorced from those that…

  9. A Study of Equating in NAEP. NAEP Validity Studies.

    ERIC Educational Resources Information Center

    Hedges, Larry V.; Vevea, Jack L.

    This study investigates the amount of uncertainty added to National Assessment of Educational Progress (NAEP) estimates by equating error under both ideal and less than ideal circumstances. Data from past administrations are used to guide simulations of various equating designs and error due to equating is estimated empirically. The design…

  10. 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

  11. 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.

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

    PubMed

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

    2013-01-01

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

  13. 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.

  14. 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...

  15. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... below, evidence of validity specific to each unit will not be required unless there are variables which are likely to affect validity significantly. D. Other significant variables. If there are variables...

  16. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... below, evidence of validity specific to each unit will not be required unless there are variables which are likely to affect validity significantly. D. Other significant variables. If there are variables...

  17. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... below, evidence of validity specific to each unit will not be required unless there are variables which are likely to affect validity significantly. D. Other significant variables. If there are variables...

  18. Assessing interpersonal aspects of schizoid personality disorder: preliminary validation studies.

    PubMed

    Kosson, David S; Blackburn, Ronald; Byrnes, Katherine A; Park, Sohee; Logan, Caroline; Donnelly, John P

    2008-03-01

    In 2 studies, we examined the reliability and validity of an interpersonal measure of schizoid personality disorder (SZPD) based on nonverbal behaviors and interpersonal interactions occurring during interviews. A total of 556 male jail inmates in the United States participated in Study 1; 175 mentally disordered offenders in maximum security hospitals in the United Kingdom participated in Study 2. Across both samples, scores on the Interpersonal Measure of Schizoid Personality Disorder (IM-SZ) exhibited adequate reliability and patterns of correlations with other measures consistent with expectations. The scale displayed patterns of relatively specific correlations with interview and self-report measures of SZPD. In addition, the IM-SZ correlated in an expected manner with features of psychopathy and antisocial personality and with independent ratings of interpersonal behavior. We address implications for assessment of personality disorder.

  19. [Study of the validity and reproducibility of passive ozone monitors].

    PubMed

    Cortez-Lugo, M; Romieu, I; Palazuelos-Rendón, E; Hernández-Avila, M

    1995-01-01

    The aim of this study was to evaluate the validity and reproducibility between ozone measurements obtained with passive ozone monitors and those registered with a continuous ozone monitor, to determine the applicability of passive monitors in epidemiological research. The study was carried out during November and December 1992. Indoor and outdoor classroom air ozone concentrations were analyzed using 28 passive monitors and using a continuous monitor. The correlation between both measurements was highly significant (r = 0.089, p < 0.001), indicating a very good validity. Also, the correlation between the measurements obtained with two different passive monitors exposed concurrently was very high (r = 0.97, p < 0.001), indicating a good reproducibility in the measurements of the passive monitors. The relative error between the concentrations measured by the passive monitors and those from the continuous monitor tended to decrease with increasing ozone concentrations. The results suggest that passive monitors should be used to determine cumulative exposure of ozone exceeding 100 ppb, corresponding to an exposure period greater than five days, if used to analyze indoor air.

  20. 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.

  1. 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

  2. Phase behaviour and conductivity study of electrolytes in supercritical hydrofluorocarbons.

    PubMed

    Bartlett, Philip N; Cook, David C; George, Michael W; Ke, Jie; Levason, William; Reid, Gillian; Su, Wenta; Zhang, Wenjian

    2011-01-01

    The purpose of this work was to characterise supercritical hydrofluorocarbons (HFC) that can be used as solvents for electrodeposition. The phase behaviour of CHF(3), CH(2)F(2), and CH(2)FCF(3) containing [NBu(n)(4)][BF(4)], [NBu(n)(4)][B{3,5-C(6)H(3)(CF(3))(2)}(4)] and Na[B{3,5-C(6)H(3)(CF(3))(2)}(4)] was studied and the conditions for forming a single supercritical phase established. Although all three HFCs are good solvents for [NBu(n)(4)][BF(4)] the results show that the CH(2)F(2) system has the lowest p(r) for dissolving a given amount of [NBu(n)(4)][BF(4)]. The solubility of Na[B{3,5-C(6)H(3)(CF(3))(2)}(4)] in CH(2)F(2) was found to be unexpectedly high. Studies of the phase behaviour of CH(2)F(2) containing [NBu(n)(4)][BF(4)] and [Cu(CH(3)CN)(4)][BF(4)] showed that the copper complex was unstable in the absence of CH(3)CN. For CHF(3), [Cu(hfac)(2)] was more soluble and more stable than [Cu(CH(3)CN)(4)][BF(4)] and only increased the phase-separation pressure by a moderate amount. Studies of the conductivity of [NBu(n)(4)][B(C(6)F(5))(4)], [NBu(n)(4)][B{3,5-C(6)H(3)(CF(3))(2)}(4)], [NR(f)Bu(n)(3)][B{3,5-C(6)H(3)(CF(3))(2)}(4)] (R(f) = (CH(2))(3)C(7)F(15)), and Na[B{3,5-C(6)H(3)(CF(3))(2)}(4)] were carried out in scCH(2)F(2). The results show that these salts are more conducting than [NBu(n)(4)][BF(4)] under the same conditions although the increase is much less significant than that reported in previous work in supercritical CO(2) + CH(3)CN. Consequently, either [NBu(n)(4)][BF(4)] or the corresponding BARF salts would be suitable background electrolytes for electrodeposition from scCH(2)F(2). PMID:21072413

  3. 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

  4. 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

    2014-04-03

    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.

  5. 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.

  6. Patient-initiated postmarketing surveillance: a validation study.

    PubMed

    Fisher, S; Bryant, S G; Solovitz, B L; Kluge, R M

    1987-11-01

    A new patient-initiated, pharmacy-based postmarketing surveillance system is described. At the time a new prescription for a targeted drug was filled, 2705 outpatients (experimentals) randomly assigned to the new system had a printed notice attached to their medication bags: the information requested them to report any "new or unusual symptoms" during the next 2 weeks by a toll-free telephone number to a trained nonprofessional who conducted a standardized adverse drug reaction (ADR) interview. To help validate the new system, another sample of 1109 patients (controls) did not receive a request for self-monitoring but were interviewed by telephone 2 weeks later. Target drugs were chosen from two classes for which side effect profiles are well identified: oral antibiotics and tricyclic antidepressants. Results show that within both drug classes, all patient-initiated reports closely matched those obtained from controls; the experimental and control groups also reported predictably high relative frequencies for the most commonly expected ADRs. Additional analyses suggest that a patient-initiated monitoring system could prove to be a promising complement to existing physician-based surveillance systems. PMID:3429691

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

    SciTech Connect

    Dowding, Kevin J.; Leslie, Ian H.; Hobbs, Michael L.; Rutherford, Brian Milne; Hills, Richard Guy; Pilch, Martin M.

    2004-10-01

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

  8. Validation Study of the Integral-Differential Scheme for Multi-Block Grids

    NASA Astrophysics Data System (ADS)

    Mrema, Honest Frank

    This MS Thesis seeks to validate the accuracy of the Integral-Differential Scheme (IDS). In the attempts to accomplish this task, research efforts were focused on the scheme's ability to capture the physics of known flow fields, as well as the scheme's ability to predict the features of flow field quantities that may be derived from experimental measurements. The IDS was developed with the goal of being computationally efficient, from a programming perspective, as well as being numerically accurate, stable, and robust, from a mathematical perspective. The IDS is designed to solve the full Navier-Stokes equations in their integral forms. Unlike traditional control volume schemes, the IDS is built upon two sets of cells: spatial and temporal cells. For 2-D flows, the IDS considers an elementary control volume as a collection of four spatial cells and a single temporal cell. Similar to other explicit CFD schemes, the IDS relies on the use of the Taylor series expansion and other traditional CFD criteria. It is of interest to note that there are previous IDS validation studies which were conducted at North Carolina A&T State University. These past studies mainly focused on the qualitative aspects of the flow field physics. Furthermore, in all cases, they focused on flow field problems that can be represented by single-block grids. In this analysis, the validation studies are focused on multi-block grids in which the physics of the flow field is made complicated due to the presence of shock waves and flow separation zones. Of interest to this MS Thesis are two supersonic flow field problems that are supported by experimental data; namely, the supersonic flow over a rearward-facing step problem and the supersonic flow over a cavity problem. The validation studies conducted herein demonstrated that the IDS was able to predict the experimental data in both cases.

  9. 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.

  10. The Cancer Message Literacy Tests: Psychometric Analyses and Validity Studies

    PubMed Central

    Mazor, Kathleen M.; Rogers, H. Jane; Williams, Andrew E.; Roblin, Douglas W.; Gaglio, Bridget; Field, Terry S.; Greene, Sarah M.; Han, Paul K. J.; Costanza, Mary E.

    2012-01-01

    Objectives To examine the psychometric properties of two new health literacy tests, and to evaluate score validity. Methods Adults aged 40 to 71 completed the Cancer Message Literacy Test-Listening (CMLT- Listening), the Cancer Message Literacy Test-Reading (CMLT-Reading), the REALM, the Lipkus numeracy test, a brief knowledge test (developed for this study) and five brief cognitive tests. Participants also self-reported educational achievement, current health, reading ability, ability to understand spoken information, and language spoken at home. Results Score reliabilities were good (CMLT-Listening: alpha = .84) to adequate (CMLT-Reading: alpha =.75). Scores on both CMLT tests were positively and significantly correlated with scores on the REALM, numeracy, cancer knowledge and the cognitive tests. Mean CMLT scores varied as predicted according to educational level, language spoken at home, self-rated health, self-reported reading, and self-rated ability to comprehend spoken information. Conclusions The psychometric findings for both tests are promising. Scores appear to be valid indicators of comprehension of spoken and written health messages about cancer prevention and screening. Practice Implications The CMLT-Listening will facilitate research into comprehension of spoken health messages, and together with the CMLT-Reading will allow researchers to examine the unique contributions of listening and reading comprehension to health-related decisions and behaviors. PMID:22789147

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

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Pradhan, Sulolit; Chen, Shaowei

    2011-05-01

    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

  12. Study for Electric Device Assembly Process Using Conductive Adhesive

    NASA Astrophysics Data System (ADS)

    Fujino, Junji

    Electric devices with semiconductors are applied to all apparatus including substation equipment, transport machines, home electronics, and cellular phones. Power modules deal large current, and high frequency/optical modules control GHz band signals. As a result, these semiconductors have more than 100 times heat density of memory or MPU chips. Pb-rich high temperature solder and expensive Au-rich solder are applied to these modules, however, thermal stress might be a problem not only for long-term reliability but also for the initial characteristics. The authors studied the assembly of these electric devices using conductive adhesive as a substitute bonding material. We proved that atmospheric aluminum oxides caused electric resistance and that power chips with long rectangle sides over 10 mm have a much larger thermal resistance than theoretical values. We found that it is effective to scratch and remove these oxides through transferred adhesive on aluminum electrodes and to diebond them onto the solder projection previously formed on the die pads.

  13. A numerical study of transient, thermally-conductive solar wind

    NASA Technical Reports Server (NTRS)

    Han, S. M.; Wu, S. T.; Dryer, M.

    1987-01-01

    A numerical analysis of transient solar wind starting at the solar surface and arriving at 1 AU is performed by an implicit numerical method. The model hydrodynamic equations include thermal conduction terms for both steady and unsteady simulations. Simulation results show significant influence of thermal conduction on both steady and time-dependent solar wind. Higher thermal conduction results in higher solar wind speed, higher temperature, but lower plasma density at 1 AU. Higher base temperature at the solar surface gives lower plasma speed, lower temperature, but higher density at 1 AU. Higher base density, on the other hand, gives lower velocity, lower temperature, but higher density at 1 AU.

  14. Experience Tables, Predictive Validity Studies, and Validation of Placement Tables for the MDTP Placement Tests.

    ERIC Educational Resources Information Center

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

    California's College of the Canyons has used the four Mathematics Diagnostic Testing Project (MDTP) tests to assess students' abilities in basic and college math since spring 1989. These four reports dated June 1993, July 1993, May 1994, and June 1994 examine the predictive validity of the MDTP tests and the cut scores used to place students. The…

  15. 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

  16. 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

  17. 'Schizoid' personality and antisocial conduct: a retrospective case not study.

    PubMed

    Wolff, S; Cull, A

    1986-08-01

    A retrospective case not analysis for 30 boys diagnosed as having a 'schizoid' personality disorder (Asperger's syndrome) in childhood, and for 30 matched clinic attenders (with systematic follow-up data for 19 matched pairs), showed the incidence of antisocial conduct to be the same in the two groups. However, the 'schizoid' boys stole less often and had fewer alcohol problems. In this group antisocial conduct was less related to family disruption and social disadvantage, and more to an unusual fantasy life. Clinical descriptions of a series of 'schizoid' boys and girls with conspicuous antisocial conduct follow. They suggest that characteristic patterns of antisocial conduct in such children are persistent expressions of hostility and, especially in girls, pathological lying, for which environmental circumstances provide no explanation.

  18. Carbonyl mediated conductance through metal bound peptides: a computational study

    NASA Astrophysics Data System (ADS)

    Perrine, Trilisa M.; Dunietz, Barry D.

    2007-10-01

    Large increases in the conductance of peptides upon binding to metal ions have recently been reported experimentally. The mechanism of the conductance switching is examined computationally. It is suggested that oxidation of the metal ion occurs after binding to the peptide. This is caused by the bias potential placed across the metal-peptide complex. A combination of configurational changes, metal ion involvement and interactions between carbonyl group oxygen atoms and the gold leads are all shown to be necessary for the large improvement in the conductance seen experimentally. Differences in the molecular orbitals of the nickel and copper complexes are noted and serve to explain the variation of the improvement in conductance upon binding to either a nickel or copper ion.

  19. [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

  20. [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.

  1. Goals of care among hospitalized patients: a validation study.

    PubMed

    Haberle, Tyler H; Shinkunas, Laura A; Erekson, Zachary D; Kaldjian, Lauris C

    2011-08-01

    Our objective was to validate 6 literature-derived goals of care by analyzing open-ended and closed-ended responses about goals of care from a previous study of hospitalized patients. Eight clinicians categorized patients' open-ended articulations of their goals of care using a literature-derived framework and then compared those categorizations to patients' own closed-ended selections of their most important goal of care. Clinicians successfully categorized patients' open-ended responses using the literature-derived framework 83.5% of the time, and their categorizations matched patients' closed-ended most important goal of care 87.8% of the time. Goals that did not fit within the literature-derived framework all pertained to the goal of understanding a patient's diagnosis or prognosis; this seventh potential goal can be added to the literature-derived framework of 6 goals of care.

  2. A quantitative approach to perceived health status: a validation study.

    PubMed

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

    1980-12-01

    The current recognition of the importance of perceived health status as a predictor of need for, and utilisation of, health services has led to attempts to produce indicators which assess subjective rather than objective health problems. The development of the Nottingham Health Profile is described, together with a study which tested the validity of the instrument on four groups of elderly people differing in health status. The results showed that the profile was capable of discriminating between groups differing in terms of diagnosed chronic illness, number of consultations at primary care level, and physiological fitness. Age, sex, and marital status were not significant overall in affecting scores. In these elderly subjects, perceived health status accorded well with objective health status. Further tests of the profile are now taking place on younger groups of subjects. PMID:7241028

  3. New York State TrueAllele ® casework validation study.

    PubMed

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

    2013-11-01

    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.

  4. 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…

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. The Anomalous Sentences Repetition Test: Replication and Validation Study.

    ERIC Educational Resources Information Center

    Weeks, David J.

    1986-01-01

    Presents a brief clinical test, derived from earlier neuropsychological instruments, with evidence for its reliability, interscorer agreement, and validity. The latter is based upon correlations with both CAT scan measures of cortical atrophy and ventricular enlargement, as well as correlations with seven other previously validated cognitive…

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

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., such as those described in the Standards for Educational and Psychological Tests prepared by a joint... they become accepted by the psychological profession. B. Criterion-related, content, and construct validity. Evidence of the validity of a test or other selection procedure by a criterion-related...

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., such as those described in the Standards for Educational and Psychological Tests prepared by a joint... they become accepted by the psychological profession. B. Criterion-related, content, and construct validity. Evidence of the validity of a test or other selection procedure by a criterion-related...

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

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., such as those described in the Standards for Educational and Psychological Tests prepared by a joint... they become accepted by the psychological profession. B. Criterion-related, content, and construct validity. Evidence of the validity of a test or other selection procedure by a criterion-related...

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., such as those described in the Standards for Educational and Psychological Tests prepared by a joint... they become accepted by the psychological profession. B. Criterion-related, content, and construct validity. Evidence of the validity of a test or other selection procedure by a criterion-related...

  14. 29 CFR 1607.5 - General standards for validity studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., such as those described in the Standards for Educational and Psychological Tests prepared by a joint... they become accepted by the psychological profession. B. Criterion-related, content, and construct validity. Evidence of the validity of a test or other selection procedure by a criterion-related...

  15. Validity Shrinkage in Ridge Regression: A Simulation Study.

    ERIC Educational Resources Information Center

    Faden, Vivian; Bobko, Philip

    1982-01-01

    Ridge regression offers advantages over ordinary least squares estimation when a validity shrinkage criterion is considered. Comparisons of cross-validated multiple correlations indicate that ridge estimation is superior when the predictors are multicollinear, the number of predictors is large relative to sample size, and the population multiple…

  16. 29 CFR 1607.14 - Technical standards for validity studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 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 technically... the primary focus of the test are those which employees learn on the job. Where samples are...

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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.

  4. 41 CFR 60-3.14 - Technical standards for validity studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... specific validation strategy used. B. Technical standards for criterion-related validity studies—(1... strategy should determine whether it is technically feasible (as defined in section 16) to conduct such a... those which employees learn on the job. Where samples are combined or compared, attention should...

  5. 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

  6. 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

  7. Spectroscopic ellipsometry study of novel nanostructured transparent conducting oxide structures

    NASA Astrophysics Data System (ADS)

    Khosroabadi, Akram A.; Norwood, R. A.

    2013-02-01

    Spectroscopic ellipsometry has been used to find the optical constants, including refractive index, extinction coefficient, thickness and volume fraction of nanostructured transparent conducting oxides including indium tin oxide (ITO) and indium zinc oxide (IZO). We observed sharp features in the ellipsometry data, with the spectral peaks and positions depending on the nanostructure dimensions and material. A superposition of Lorentzian oscillators and the effective medium approximation has been applied to determine the volume ratio of voids and nanopillars, thereby providing the effective optical constants.

  8. Conducting Online Expert panels: a feasibility and experimental replicability study

    PubMed Central

    2011-01-01

    Background This paper has two goals. First, we explore the feasibility of conducting online expert panels to facilitate consensus finding among a large number of geographically distributed stakeholders. Second, we test the replicability of panel findings across four panels of different size. Method We engaged 119 panelists in an iterative process to identify definitional features of Continuous Quality Improvement (CQI). We conducted four parallel online panels of different size through three one-week phases by using the RAND's ExpertLens process. In Phase I, participants rated potentially definitional CQI features. In Phase II, they discussed rating results online, using asynchronous, anonymous discussion boards. In Phase III, panelists re-rated Phase I features and reported on their experiences as participants. Results 66% of invited experts participated in all three phases. 62% of Phase I participants contributed to Phase II discussions and 87% of them completed Phase III. Panel disagreement, measured by the mean absolute deviation from the median (MAD-M), decreased after group feedback and discussion in 36 out of 43 judgments about CQI features. Agreement between the four panels after Phase III was fair (four-way kappa = 0.36); they agreed on the status of five out of eleven CQI features. Results of the post-completion survey suggest that participants were generally satisfied with the online process. Compared to participants in smaller panels, those in larger panels were more likely to agree that they had debated each others' view points. Conclusion It is feasible to conduct online expert panels intended to facilitate consensus finding among geographically distributed participants. The online approach may be practical for engaging large and diverse groups of stakeholders around a range of health services research topics and can help conduct multiple parallel panels to test for the reproducibility of panel conclusions. PMID:22196011

  9. 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…

  10. A study of electron beam-induced conductivity in resists.

    PubMed

    Hwu, J J; Joy, D C

    1999-01-01

    The charging of polymeric resist materials during electron beam irradiation leads to significant problems during imaging and lithography processes. Charging occurs because of charge deposition in the polymer and charge generation/trapping due to formation of electron-hole pairs in the dielectric. The presence of such charge also results in the phenomena of electron beam-induced conductivity (EBIC). Electron beam-induced conductivity data have been obtained for three commercial e-beam resists under a variety of dose rate and temperature conditions. From the observed values of induced conductivity under varying conditions significant information about the generation of electron-hole pair and the transport of charge in the resist can be obtained. Three electron beam resists, EBR900, ZEP7000, and PBS are examined by an external bias method. The difference in resist chemistry is considered to play the role in the initial state EBIC behaviors among three resists even though the way that it affects the behaviors is not clear. A comparison of the power consumption comparison is proposed as a measure to give a preliminary estimate of the carrier concentration and carrier drift velocity differences among the resists. A simple single trap model with constant activation energy is proposed and provides good agreement with experiment.

  11. 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

  12. 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

  13. 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…

  14. Dimensionality of Teacher Educational Beliefs: A Validation Study.

    ERIC Educational Resources Information Center

    Bunting, Carolyn E.

    1985-01-01

    To validate a previous measure of teachers' educational beliefs which yielded four factors, a new, longer measure was administered to 320 elementary school teachers. The results yielded two dimensions, namely student-centered and directive teaching. (Author/GDC)

  15. 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)

  16. [Educational game of medication administration: a validation study].

    PubMed

    Moreira, Amanda Portugal de Andrade; Sabóia, Vera Maria; Camacho, Alessandra Conceição Leite Funchal; Daher, Donizete Vago; Teixeira, Elizabeth

    2014-01-01

    This is a methodological research, which aimed to determine the validity of an educational technology (ET) in the form of educational game of medicine administration, according to the judges and audience, using the theoretical stage of Pasquali model. Data were collected between September 2011 and May 2012 in two stages: 1) application and validation of TE by forty students of the 4th period of Nursing, at the Fluminense Federal University (target audience); 2) observation and validation of TE by 8 teachers (judges). The questionnaires were organized in Likert scale, with items distributed in blocks and analyzed quantitatively. The game was validated, since it has over 80% approval by the two groups, and may therefore be used as a TE in the discipline of Fundamentals of Nursing. The results were positive, demonstrating that students and teachers are more interested in content taught when most dynamic technologies are used in the classroom.

  17. MINET validation study using steam generator test data

    SciTech Connect

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

    1984-01-01

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

  18. 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.

  19. 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

  20. 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.

  1. Ambulatory impedance cardiography in hypertension: a validation study.

    PubMed

    McFetridge-Durdle, Judith A; Routledge, Faye S; Parry, Monica J E; Dean, C R T; Tucker, B

    2008-09-01

    The management of hypertension is improved by knowledge of the hemodynamics underlying blood pressure. Impedance Cardiography (ICG) provides data on a range of hemodynamic variables that affect blood pressure. However, ICG captures only fixed descriptions of hemodynamic characteristics. Improvements in ambulatory technology have led to the development of the Ambulatory Impedance Monitor (AIM) which records hemodynamic data during the activities of daily living. The purpose of this study was to evaluate the sensitivity of the AIM to detect hemodynamic changes associated with postural shift in persons with hypertension. Using a repeated measures cross-over design, sitting and standing hemodynamic measures were taken in seventeen persons with hypertension while wearing the AIM-BpTRU system designed for standard office use and the AIM-Spacelabs system designed for ambulatory monitoring. Both AIM-blood pressure monitoring systems detected significant changes from sitting to standing posture in heart rate (p=0.03), stroke volume (p=0.002), left ventricular ejection time (p<0.001), systemic vascular resistance (p=0.03) and diastolic blood pressure (p<0.001). Additionally, both systems generated measures of cardiac function that were positively correlated (p<0.001) and not significantly different (p>0.05). Our findings support previous work and demonstrate that the AIM provides valid and reliable estimates of cardiac function in persons with hypertension. PMID:18234557

  2. Single molecule study of DNA conductivity in aqueous environment.

    PubMed

    Legrand, O; Côte, D; Bockelmann, U

    2006-03-01

    The dc electrical conductivity of double stranded DNA is investigated experimentally. Single DNA molecules are manipulated with subpiconewton force and deposited on gold nanoelectrodes by optical traps. The DNA is modified at its ends for specific bead attachments and along the chain to favor charge transfer between the DNA base pair stack and the electrodes. For an electrode separation of 70 nm we find, in aqueous environment, electrical resistances above 100 G Omega indicating that even for weak stretching the double helix is almost insulating at this length scale.

  3. Single molecule study of DNA conductivity in aqueous environment

    NASA Astrophysics Data System (ADS)

    Legrand, O.; Côte, D.; Bockelmann, U.

    2006-03-01

    The dc electrical conductivity of double stranded DNA is investigated experimentally. Single DNA molecules are manipulated with subpiconewton force and deposited on gold nanoelectrodes by optical traps. The DNA is modified at its ends for specific bead attachments and along the chain to favor charge transfer between the DNA base pair stack and the electrodes. For an electrode separation of 70nm we find, in aqueous environment, electrical resistances above 100GΩ indicating that even for weak stretching the double helix is almost insulating at this length scale.

  4. A Validation Study of the Dutch Childhood Trauma Questionnaire-Short Form: Factor Structure, Reliability, and Known-Groups Validity

    ERIC Educational Resources Information Center

    Thombs, Brett D.; Bernstein, David P.; Lobbestael, Jill; Arntz, Arnoud

    2009-01-01

    Objective: The 28-item Childhood Trauma Questionnaire-Short Form (CTQ-SF) has been translated into at least 10 different languages. The validity of translated versions of the CTQ-SF, however, has generally not been examined. The objective of this study was to investigate the factor structure, internal consistency reliability, and known-groups…

  5. 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.

  6. Electrokinetic experimental study on saturated rock samples: zeta potential and surface conductance

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Hu, Hengshan; Guan, Wei; Li, Hui

    2015-05-01

    It is important to know the electrokinetic properties of crustal rocks for interpreting the conductivity mechanisms and seismoelectric phenomena during earthquakes and seismoelectric well logging. In this study, electrokinetic experiments are conducted using a special core-holder by employing an AC lock-in technique. A series of experiments are conducted on 10 sandstone samples to measure the streaming potentials and streaming currents, and the experiments on each sample are done at six different salinities. The streaming potential coefficient and streaming current coefficient are calculated from the measured streaming potentials and streaming currents. The experimental results show that streaming potential coefficient and streaming current coefficient decrease as the salinity increases. The dependence of these two coefficients on permeability and pore radius are analysed and compared with previous works. At low salinities, the streaming potential coefficient and streaming current coefficient increase with the increasing permeability and pore radius. At high salinities, the streaming potential coefficient (streaming current coefficient) almost share a same value for 10 different samples. This conclusion indicates that the differences of rock parameters can only be well recognized at lower salinities, and the electrokinetic signals are invalid at high salinities, which offers a restrictive condition for using the amplitude of electrokinetic signals to estimate rock parameters. The zeta-potential have also been estimated through combined measurements of streaming potential and streaming current. The surface conductivity and its contribution to electrokinetic effects are determined from a comparison of zeta-potentials by two different methods, and then the validation of the Helmholz-Smoluchowski equation for a capillary tube is tested in rocks. We also compare our date with theoretical and experimental works, and set up an expression about the relationship between

  7. 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

  8. 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.

  9. Conducting systematic reviews of diagnostic studies: didactic guidelines

    PubMed Central

    Devillé, Walter L; Buntinx, Frank; Bouter, Lex M; Montori, Victor M; de Vet, Henrica CW; van der Windt, Danielle AWM; Bezemer, P Dick

    2002-01-01

    Background Although guidelines for critical appraisal of diagnostic research and meta-analyses have already been published, these may be difficult to understand for clinical researchers or do not provide enough detailed information. Methods Development of guidelines based on a systematic review of the evidence in reports of systematic searches of the literature for diagnostic research, of methodological criteria to evaluate diagnostic research, of methods for statistical pooling of data on diagnostic accuracy, and of methods for exploring heterogeneity. Results Guidelines for conducting diagnostic systematic reviews are presented in a stepwise fashion and are followed by comments providing further information. Examples are given using the results of two systematic reviews on the accuracy of the urine dipstick in the diagnosis of urinary tract infections, and on the accuracy of the straight-leg-raising test in the diagnosis of intervertebral disc hernia. PMID:12097142

  10. Alaska North Slope Tundra Travel Model and Validation Study

    SciTech Connect

    Harry R. Bader; Jacynthe Guimond

    2006-03-01

    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.

  11. The feasibility and validity of a remote pulse oximetry system for pulmonary rehabilitation: a pilot study.

    PubMed

    Tang, Jonathan; Mandrusiak, Allison; Russell, Trevor

    2012-01-01

    Pulmonary rehabilitation is an effective treatment for people with chronic obstructive pulmonary disease. However, access to these services is limited especially in rural and remote areas. Telerehabilitation has the potential to deliver pulmonary rehabilitation programs to these communities. The aim of this study was threefold: to establish the technical feasibility of transmitting real-time pulse oximetry data, determine the validity of remote measurements compared to conventional face-to-face measures, and evaluate the participants' perception of the usability of the technology. Thirty-seven healthy individuals participated in a single remote pulmonary rehabilitation exercise session, conducted using the eHAB telerehabilitation system. Validity was assessed by comparing the participant's oxygen saturation and heart rate with the data set received at the therapist's remote location. There was an 80% exact agreement between participant and therapist data sets. The mean absolute difference and Bland and Altman's limits of agreement fell within the minimum clinically important difference for both oxygen saturation and heart rate values. Participants found the system easy to use and felt confident that they would be able to use it at home. Remote measurement of pulse oximetry data for a pulmonary rehabilitation exercise session was feasible and valid when compared to conventional face-to-face methods.

  12. Deconstructing major depression: a validation study of the DSM-IV symptomatic criteria

    PubMed Central

    Lux, V.; Kendler, K. S.

    2010-01-01

    Background The DSM-IV symptomatic criteria for major depression (MD) derive primarily from clinical experience with modest empirical support. Method The sample studied included 1015 (518 males, 497 females) Caucasian twins from a population-based registry who met criteria for MD in the year prior to the interview. Logistic regression analyses were conducted to compare the associations of: (1) single symptomatic criterion, (2) two groups of criteria reflecting cognitive and neurovegetative symptoms, with a wide range of potential validators including demographic factors, risk for future episodes, risk of MD in the co-twin, characteristics of the depressive episode, the pattern of co-morbidity and personality traits. Results The individual symptomatic criteria showed widely varying associations with the pattern of co-morbidity, personality traits, features of the depressive episode and demographic characteristics. When examined separately, these two criteria groups showed robust differences in their patterns of association, with the validators with the cognitive criteria generally producing stronger associations than the neurovegetative. Conclusions Among depressed individuals, individual DSM-IV symptomatic criteria differ substantially in their predictive relationship with a range of clinical validators. These results challenge the equivalence assumption for the symptomatic criteria for MD and suggest a more than expected degree of ‘ covert ’ heterogeneity among these criteria. Part of this heterogeneity is captured by the distinction between cognitive versus neurovegetative symptoms, with cognitive symptoms being more strongly associated with most clinically relevant characteristics. Detailed psychometric evaluation of DSM-IV criteria is overdue. PMID:20059797

  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. 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

  15. Propeller aircraft interior noise model utilization study and validation

    NASA Astrophysics Data System (ADS)

    Pope, L. D.

    1984-09-01

    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.

  16. 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.

  17. The Study of Diagnostic Efficacy of Nerve Conduction Study Parameters in Cervical Radiculopathy

    PubMed Central

    Pawar, Sachin; Kashikar, Aditi; Shende, Vinod; Waghmare, Satish

    2013-01-01

    Background: Cervical Radiculopathy (CR) is a neurologic condition characterised by dysfunction of a cervical spinal nerve, the roots of the nerve, or both. Diagnostic criteria for CR are not well defined, and no universally accepted criteria for its diagnosis have been established. Clinical examination, radiological imaging and electrophysiologic evaluation are the different modalities to diagnose CR. The incidence of Cervical Spondylosis and related conditions is increasing in the present scenario and the use of radiologic examination is time consuming and uneconomical for the common Indian setup. Thus, there is a definite need to establish a cost effective, reliable, and accurate means for establishing the diagnosis of cervical radiculopathy. Electrodiagnostic tests are the closest to fulfill these criteria. Aim: To evaluate diagnostic utility of various motor and sensory nerve conduction study parameters in cervical radiculopathy. Setting and Design: It was a cross-sectional study conducted on 100 subjects of age > 40 years. Material and Methods: The consecutive patients clinically diagnosed to have cervical radiculopathy, referred from department of Orthopaedics were prospectively recruited for the motor and sensory nerve conduction study using RMS EMG EP Mark-II. Parameters studied were Compound Muscle Action Potential (CMAP), Distal Motor Latency (DML) and Conduction Velocity (CV) for motor nerves and Sensory Nerve Action Potential (SNAP) and CV for sensory nerves. Statistical Analysis: Study observations and results were analysed to find the Specificity, Sensitivity, Positive Predictive Value and Negative Predictive Value using SPSS 16.0. Results: Among various motor nerve conduction parameters CMAP was found to be more sensitive with high positive predicative value. CV was found to have greater specificity and DML had least negative predictive value. Sensory nerve conduction parameters were found to have less sensitivity but higher specificity as compared

  18. Contributions of Middle Grade Students to the Validation Process of a National Science Assessment Study

    ERIC Educational Resources Information Center

    Morell, Linda

    2008-01-01

    This study used a national validity project to investigate specific research questions regarding the intersections among aspects of validity, educational measurement, and cognitive theory. Validity evidence was collected through traditional paper and pencil tests, surveys, think-alouds, and exit interviews of fifth and sixth grade students, as…

  19. 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…

  20. Fun and Games: The Validity of Games for the Study of Conflict

    ERIC Educational Resources Information Center

    Schlenker, Barry R.; Bonoma, Thomas V.

    1978-01-01

    Examines claimed advantages and criticisms of the use of games in the study of social conflict, differentiating the advantages and criticisms into questions of internal validity, external validity, and ecological validity. Available from: Sage Publications, Inc., 275 South Beverly Drive, Beverly Hills, California 90212. (JG)

  1. Lessons Learned from CFD Validation Study of Protuberance Heating

    NASA Technical Reports Server (NTRS)

    Oliver, Brandon; Blaisdell, Greogory

    2011-01-01

    The objectives of this presentation are: (1) Share lessons learned from a recent exercise in CFD validation of protuberance heating (2) Impact of experimental data reduction assumptions and techniques on validation activity (3) Advanced data reduction techniques may provide useful data from non-typical test methods (4) Significance of the recovery factor for high-speed flows (5) Show typical results of the Lag turbulence model on protuberances (6) Introduce and inform the listener of a protuberance heating dataset which will soon be available for comparison

  2. 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.

  3. Subsurface Immobilization of Plutonium: Experimental and Model Validation Studies

    SciTech Connect

    Rittmann, Bruce E; Deo, Randhir P; Reed, Donald T

    2008-08-13

    We conducted a coordinated experimental and modeling study centered on the interaction of Shewanella alga BrY (S. alga) with plutonium species and phases. Plutonium is the key contaminant of concern at several DOE sites that are being addressed by the overall ERSP program. The over-arching goal of this research was to understand the long-term stability of bio-precipitated immobilized plutonium phases under changing redox conditions in biologically active systems. To initiate the process of plutonium immobilization, a side-by-side comparison of the bioreduction of uranyl and plutonyl species was conducted with S. alga. Uranyl was reduced in our system, consistent with literature reports, but we noted coupling between abiotic and biotic processes and observed that non-reductive pathways to precipitation typically exist. Additionally, a key role of biogenic Fe2+, which is known to reduce uranyl at low pH, is suggested. In contrast, residual organics, present in biologically active systems, reduce Pu(VI) species to Pu(V) species at near-neutral pH. The predominance of relatively weak complexes of PuO2+ is an important difference in how the uranyl and plutonyl species interacted with S. alga. Pu(V) also led to increased toxicity towards S. alga and is also more easily reduced by microbial activity. Biogenic Fe2+, produced by S. alga when Fe3+ is present as an electron acceptor, also played a key role in understanding redox controls and pathways in this system. Overall, the bioreduction of plutonyl was observed under anaerobic conditions, which favor its immobilization in the subsurface. Understanding the mechanism by which redox control is established in biologically active systems is a key aspect of remediation and immobilization strategies for actinides when they are present as subsurface contaminants.

  4. Mechanistic study of silver nanoparticle formation on conducting polymer surfaces.

    PubMed

    Mack, Nathan H; Bailey, James A; Doorn, Stephen K; Chen, Chien-An; Gau, Han-Mou; Xu, Ping; Williams, Darrick J; Akhadov, Elshan A; Wang, Hsing-Lin

    2011-04-19

    Conducting polymer (polyaniline) sheets are shown to be active substrates to promote the growth of nanostructured silver thin films with highly tunable morphologies. Using the spontaneous electroless deposition of silver, we show that a range of nanostructured metallic features can be controllably and reproducibly formed over large surface areas. The structural morphology of the resulting metal-polymer nanocomposite is demonstrated to be sensitive to experimental parameters such as ion concentration, temperature, and polymer processing and can range from densely packed oblate nanosheets to bulk crystalline metals. The deposition mechanisms are explained using a diffusion-limited aggregation (DLA) model to describe the semi-fractal-like growth of the metal nanostructures. We find these composite films to exhibit strong surface-enhanced Raman (SERS) activity, and the nanostructured features are optimized with respect to SERS activity using a self-assembled monolayer of mercapto-benzoic acid as a model Raman reporter. SERS enhancements are estimated to be on the order of 10(7). Through micro-Raman SERS mapping, these materials are shown to exhibit uniform SERS responses over macroscopic areas. These metal-polymer nanocomposites benefit from the underlying polymer's processability to yield SERS-active materials of almost limitless shape and size and show significant promise for future SERS-based sensing and detection schemes. PMID:21434643

  5. The Predictive Validity of a Work Sample: A Laboratory Study

    ERIC Educational Resources Information Center

    Mount, Michael K.; And Others

    1977-01-01

    Concurrent and predictive test validity data and test-retest reliability data were obtained for a work sample performance measure and two paper and pencil tests in a laboratory setting. Findings are interpreted in light of a behavioral consistency model and the practical utility of work samples as a personnel selection technique. (Editor)

  6. 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…

  7. 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…

  8. A Validation Study of the AIDS Health Belief Scale.

    ERIC Educational Resources Information Center

    Scandell, Donald J.; Wlazelek, Brian

    2002-01-01

    Examined the discriminant, convergent, and criterion- related validity of the AIDS Health Belief Scale (AHBS). College students assigned to either interview or self-administration conditions completed the AHBS, a sexual behavior questionnaire, the Balanced Inventory of Desirable Responding, and the Condom Attitude Scale-Adolescent Version. There…

  9. 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…

  10. Prenatal Child Abuse Risk Assessment: A Preliminary Validation Study.

    ERIC Educational Resources Information Center

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

    2003-01-01

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

  11. 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…

  12. A Validity Study of Two Projective Object Representations Measures.

    ERIC Educational Resources Information Center

    Hibbard, Stephen; And Others

    1995-01-01

    Two projective measures of object representations, the Concept of the Object on the Rorschach and the Social Cognition and Object Relations Scales, were compared with each other and measures of intelligence and pathology with 15 children and 94 adult patients. Results support the construct validity of object representations. (SLD)

  13. 29 CFR 1607.14 - Technical standards for validity studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... analysis if the user can show the importance of the criteria to the particular employment context. These... and one or more criteria of performance on the job, and the greater the importance and number of..., leadership, and spatial ability. Content validity is also not an appropriate strategy when the...

  14. 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)

  15. 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…

  16. The global status of freshwater fish age validation studies and a prioritization framework for future research

    USGS Publications Warehouse

    Pope, Kevin L.; Hamel, Martin J.; Pegg, Mark A.; Spurgeon, Jonathan J.

    2016-01-01

    Age information derived from calcified structures is commonly used to estimate recruitment, growth, and mortality for fish populations. Validation of daily or annual marks on age structures is often assumed, presumably due to a lack of general knowledge concerning the status of age validation studies. Therefore, the current status of freshwater fish age validation studies was summarized to show where additional effort is needed, and increase the accessibility of validation studies to researchers. In total, 1351 original peer-reviewed articles were reviewed from freshwater systems that studied age in fish. Periodicity and age validation studies were found for 88 freshwater species comprising 21 fish families. The number of age validation studies has increased over the last 30 years following previous calls for more research; however, few species have validated structures spanning all life stages. In addition, few fishes of conservation concern have validated ageing structures. A prioritization framework, using a combination of eight characteristics, is offered to direct future age validation studies and close the validation information gap. Additional study, using the offered prioritization framework, and increased availability of published studies that incorporate uncertainty when presenting research results dealing with age information are needed.

  17. 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.; Barón, 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

  18. Disentangling the underlying dimensions of psychopathy and conduct problems in childhood: a community study.

    PubMed

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

    2005-06-01

    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 psychopathy in children. Factor analysis supported the structure of the APSD. Given controversy surrounding construct overlap between psychopathy and conduct problems, a factor analysis was conducted on pooled items from the Strengths and Difficulties Questionnaire and APSD. A 5-factor solution resulted: antisocial, hyperactivity, CU traits, anxiety, and peer problems. CU traits added small but significant improvements in the 12-month prediction of antisocial behavior for boys and older girls, after controlling for Time 1 measures. These results indicate that although the dimensions of the APSD overlap with dimensions of the disruptive behavior disorders, CU traits have unique predictive validity in childhood.

  19. 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

  20. Design Characteristics Influence Performance of Clinical Prediction Rules in Validation: A Meta-Epidemiological Study

    PubMed Central

    Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda

    2016-01-01

    Background Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules’ performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Methods Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. Results A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2–4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Conclusion Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved. PMID:26730980

  1. 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

  2. Cancer Appetite and Symptom Questionnaire (CASQ) for Brazilian Patients: Cross-Cultural Adaptation and Validation Study

    PubMed Central

    Serrano, Sergio Vicente; Halliday, Vanessa; Maroco, João; Campos, Juliana Alvares Duarte Bonini

    2016-01-01

    Background Appetite and symptoms, conditions generally reported by the patients with cancer, are somewhat challenging for professionals to measure directly in clinical routine (latent conditions). Therefore, specific instruments are required for this purpose. This study aimed to perform a cultural adaptation of the Cancer Appetite and Symptom Questionnaire (CASQ), into Portuguese and evaluate its psychometric properties on a sample of Brazilian cancer patients. Methods This is a validation study with Brazilian cancer patients. The face, content, and construct (factorial and convergent) validities of the Cancer Appetite and Symptom Questionnaire, the study tool, were estimated. Further, a confirmatory factor analysis (CFA) was conducted. The ratio of chi-square and degrees of freedom (χ2/df), comparative fit index (CFI), goodness of fit index (GFI) and root mean square error of approximation (RMSEA) were used for fit model assessment. In addition, the reliability of the instrument was estimated using the composite reliability (CR) and Cronbach’s alpha coefficient (α), and the invariance of the model in independent samples was estimated by a multigroup analysis (Δχ2). Results Participants included 1,140 cancer patients with a mean age of 53.95 (SD = 13.25) years; 61.3% were women. After the CFA of the original CASQ structure, 2 items with inadequate factor weights were removed. Four correlations between errors were included to provide adequate fit to the sample (χ2/df = 8.532, CFI = .94, GFI = .95, and RMSEA = .08). The model exhibited a low convergent validity (AVE = .32). The reliability was adequate (CR = .82 α = .82). The refined model showed strong invariance in two independent samples (Δχ2: λ: p = .855; i: p = .824; Res: p = .390). A weak stability was obtained between patients undergoing chemotherapy and radiotherapy (Δχ2: λ: p = .155; i: p < .001; Res: p < .001), and between patients undergoing chemotherapy combined with radiotherapy and

  3. A content validity study of the defense mechanism inventory.

    PubMed

    Blacha, M D; Fancher, R E

    1977-08-01

    The content validity of the Defense Mechanism Inventory was tested by 20 raters who evaluated each item in terms of which 15 defenses and three ego threats it represented. Items purportedly measuring the global defense categories of principalization, turning against self, and reversal, achieved relatively high rater agreement (over 70%) while projection and turning against Object fared poorly (29% and 39% respectively). Differential content validity was found in the levels and areas of the Inventory, indicating that the context in which items appear affect their representativeness of defensive behaviors. The individual defense mechanisms were disproportionately represented by the Inventory. Ratings suggested that aggressiveness was the major ego threat being measured by the items. Most of the problems appear correctable through rewriting many of the items.

  4. 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

  5. [Factor structure validity of the social capital scale used at baseline in the ELSA-Brasil study].

    PubMed

    Souto, Ester Paiva; Vasconcelos, Ana Glória Godoi; Chor, Dora; Reichenheim, Michael E; Griep, Rosane Härter

    2016-07-21

    This study aims to analyze the factor structure of the Brazilian version of the Resource Generator (RG) scale, using baseline data from the Brazilian Longitudinal Health Study in Adults (ELSA-Brasil). Cross-validation was performed in three random subsamples. Exploratory factor analysis using exploratory structural equation models was conducted in the first two subsamples to diagnose the factor structure, and confirmatory factor analysis was used in the third to corroborate the model defined by the exploratory analyses. Based on the 31 initial items, the model with the best fit included 25 items distributed across three dimensions. They all presented satisfactory convergent validity (values greater than 0.50 for the extracted variance) and precision (values greater than 0.70 for compound reliability). All factor correlations were below 0.85, indicating full discriminative factor validity. The RG scale presents acceptable psychometric properties and can be used in populations with similar characteristics.

  6. [Factor structure validity of the social capital scale used at baseline in the ELSA-Brasil study].

    PubMed

    Souto, Ester Paiva; Vasconcelos, Ana Glória Godoi; Chor, Dora; Reichenheim, Michael E; Griep, Rosane Härter

    2016-07-21

    This study aims to analyze the factor structure of the Brazilian version of the Resource Generator (RG) scale, using baseline data from the Brazilian Longitudinal Health Study in Adults (ELSA-Brasil). Cross-validation was performed in three random subsamples. Exploratory factor analysis using exploratory structural equation models was conducted in the first two subsamples to diagnose the factor structure, and confirmatory factor analysis was used in the third to corroborate the model defined by the exploratory analyses. Based on the 31 initial items, the model with the best fit included 25 items distributed across three dimensions. They all presented satisfactory convergent validity (values greater than 0.50 for the extracted variance) and precision (values greater than 0.70 for compound reliability). All factor correlations were below 0.85, indicating full discriminative factor validity. The RG scale presents acceptable psychometric properties and can be used in populations with similar characteristics. PMID:27462850

  7. Study of electrical resistivity and thermal conductivity into neutral plasma

    SciTech Connect

    Nath, G. Rout, R. K.

    2015-07-31

    The major portion of the bulk plasma in magnetospheric space, interplanetary plasma belts and the solar winds contain neutral particles. Evidently these neutral particles undergo binary collisions with the charged particles and among themselves so as to contribute significantly to the transport and diffusion process in a singly charged electron – ion magnetoplasma. The effects of the neutral particles collisions on various diffusion transport coefficients are studied for magnetised electron-ion plasma and appropriately modified coefficients are derived analytically. The results reveal that these coefficients increase significantly owing to the effect of the charge -neutral and neutral-neutral collisions.

  8. 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

  9. Ultrasound assessment of transverse carpal ligament thickness: a validity and reliability study.

    PubMed

    Shen, Zhilei Liu; Li, Zong-Ming

    2012-06-01

    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 etiologic 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 eight cadaveric specimens and eight 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 with 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 intraoperator and interoperator 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 morphologic properties of healthy and pathologic TCLs.

  10. Multicollinearity in Regression Analyses Conducted in Epidemiologic Studies

    PubMed Central

    Vatcheva, Kristina P.; Lee, MinJae; McCormick, Joseph B.; Rahbar, Mohammad H.

    2016-01-01

    The adverse impact of ignoring multicollinearity on findings and data interpretation in regression analysis is very well documented in the statistical literature. The failure to identify and report multicollinearity could result in misleading interpretations of the results. A review of epidemiological literature in PubMed from January 2004 to December 2013, illustrated the need for a greater attention to identifying and minimizing the effect of multicollinearity in analysis of data from epidemiologic studies. We used simulated datasets and real life data from the Cameron County Hispanic Cohort to demonstrate the adverse effects of multicollinearity in the regression analysis and encourage researchers to consider the diagnostic for multicollinearity as one of the steps in regression analysis. PMID:27274911

  11. 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.

  12. 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.

  13. 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.

  14. External validity of Concealed Information Test experiment: Comparison of respiration, skin conductance, and heart rate between experimental and field card tests.

    PubMed

    Zaitsu, Wataru

    2016-07-01

    The Concealed Information Test (CIT) is a memory detection method based on an examinee's physiological responses to crime-relevant items (critical items) in comparison with crime-irrelevant items (noncritical items). I examined the external validity of CIT laboratory experiments by comparing respiratory speed (RS), skin conductance response (SCR), and heart rate (HR) between a laboratory experiment (n = 30) and a field test (n = 30) in a card test. A linear mixed models analysis showed that the critical items in both CIT contexts elicited CIT effects: RS repression, SCR increase, and HR deceleration. Additionally, the critical items in the field elicited a larger RS suppression than those in the laboratory; however, SCR and HR on the critical items showed no statistical differences between the laboratory and field CITs. Moreover, the tonic HRs in the field tests were higher than in the CIT experiments, but there were no significant correlations between the tonic HR and each CIT effect in RS, SCR, and HR. These results suggested that CIT detection efficiency was not affected by arousal levels and may imply that the CIT effects observed with RS, SCR, and HR in the CIT laboratory experiments has adequate external validity and can be generalized to the CIT field. PMID:27031043

  15. External validity of Concealed Information Test experiment: Comparison of respiration, skin conductance, and heart rate between experimental and field card tests.

    PubMed

    Zaitsu, Wataru

    2016-07-01

    The Concealed Information Test (CIT) is a memory detection method based on an examinee's physiological responses to crime-relevant items (critical items) in comparison with crime-irrelevant items (noncritical items). I examined the external validity of CIT laboratory experiments by comparing respiratory speed (RS), skin conductance response (SCR), and heart rate (HR) between a laboratory experiment (n = 30) and a field test (n = 30) in a card test. A linear mixed models analysis showed that the critical items in both CIT contexts elicited CIT effects: RS repression, SCR increase, and HR deceleration. Additionally, the critical items in the field elicited a larger RS suppression than those in the laboratory; however, SCR and HR on the critical items showed no statistical differences between the laboratory and field CITs. Moreover, the tonic HRs in the field tests were higher than in the CIT experiments, but there were no significant correlations between the tonic HR and each CIT effect in RS, SCR, and HR. These results suggested that CIT detection efficiency was not affected by arousal levels and may imply that the CIT effects observed with RS, SCR, and HR in the CIT laboratory experiments has adequate external validity and can be generalized to the CIT field.

  16. 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

  17. 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

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

    PubMed

    Baker, James R; Moore, Susan M

    2011-06-01

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

  19. Validation study of gas chromatographic determination of pentachlorophenol in animal liver

    SciTech Connect

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

    1988-01-01

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

  20. 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).

  1. 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.

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

    PubMed Central

    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

  3. 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

  4. 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

  5. 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.

  6. Paraoxonase-1 Enzyme Activity Assay for Clinical Samples: Validation and Correlation Studies

    PubMed Central

    Garelnabi, Mahdi; Younis, Abdelmoneim

    2015-01-01

    Background Paraoxonase-1 (PON1) enzyme is reported in various types of tissues and linked to numerous pathophysiological disorders. It is a potential biomarker in many pathological conditions such as cardiovascular diseases. Material/Methods We conducted several small-scale studies to evaluate PON1 performance as affected by sample types, storage, and interferences. We also carried out short-term studies to compare the performance of the widely used PON1 assay to the similar commercially available PON1 kit assay method; sample size for the method comparison was N=40, and the number varied for other validation experiments. Results Our studies using various types of anticoagulants show that samples collected in tubes with NaF, citrate, EDTA, clot activator, and sodium heparin have increased PON1 levels that are 49%, 24.5%, 19.8%, 11.4%, and 8%, respectively, higher compared to serum samples collected in plain tubes. However, samples collected in lithium heparin tubes demonstrated 10.4% lower PON1 levels compared to serum collected in plain tubes. Biological interference such as hemolysis has little effect on PON1 levels; however, samples spiked with lipids have shown 13% lower PON 1 levels. Our studies comparing the PON1 method commonly available for PON1 assay and a similar non-ELISA commercially available PON1 kit method showed a weak Spearman correlation coefficient of R2=0.40 for the range of 104.9–245.6 U/L. Conclusions The current study provides new validation data on enzyme PON1 performance. While no appreciable change was seen with storage, samples type affects the enzyme performance. Our results should encourage additional clinical studies to investigate other aspects of factors known to affect PON1 enzyme function and performance. PMID:25814092

  7. A Serious Game for Clinical Assessment of Cognitive Status: Validation Study

    PubMed Central

    Chignell, Mark; Tierney, Mary C.; Lee, Jacques

    2016-01-01

    Background We propose the use of serious games to screen for abnormal cognitive status in situations where it may be too costly or impractical to use standard cognitive assessments (eg, emergency departments). If validated, serious games in health care could enable broader availability of efficient and engaging cognitive screening. Objective The objective of this work is to demonstrate the feasibility of a game-based cognitive assessment delivered on tablet technology to a clinical sample and to conduct preliminary validation against standard mental status tools commonly used in elderly populations. Methods We carried out a feasibility study in a hospital emergency department to evaluate the use of a serious game by elderly adults (N=146; age: mean 80.59, SD 6.00, range 70-94 years). We correlated game performance against a number of standard assessments, including the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and the Confusion Assessment Method (CAM). Results After a series of modifications, the game could be used by a wide range of elderly patients in the emergency department demonstrating its feasibility for use with these users. Of 146 patients, 141 (96.6%) consented to participate and played our serious game. Refusals to play the game were typically due to concerns of family members rather than unwillingness of the patient to play the game. Performance on the serious game correlated significantly with the MoCA (r=–.339, P <.001) and MMSE (r=–.558, P <.001), and correlated (point-biserial correlation) with the CAM (r=.565, P <.001) and with other cognitive assessments. Conclusions This research demonstrates the feasibility of using serious games in a clinical setting. Further research is required to demonstrate the validity and reliability of game-based assessments for clinical decision making. PMID:27234145

  8. 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. 152.92 Section 152.92 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE... Submitters' Rights § 152.92 Submission of a new valid study. An applicant may demonstrate compliance for...

  9. 40 CFR 152.92 - Submission of a new valid study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Submission of a new valid study. 152.92 Section 152.92 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE... Submitters' Rights § 152.92 Submission of a new valid study. An applicant may demonstrate compliance for...

  10. 40 CFR 152.92 - Submission of a new valid study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Submission of a new valid study. 152.92 Section 152.92 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE... Submitters' Rights § 152.92 Submission of a new valid study. An applicant may demonstrate compliance for...

  11. 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 valid study. 152.93 Section 152.93 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An applicant...

  12. 40 CFR 152.92 - Submission of a new valid study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Submission of a new valid study. 152.92 Section 152.92 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE... Submitters' Rights § 152.92 Submission of a new valid study. An applicant may demonstrate compliance for...

  13. 40 CFR 152.93 - Citation of a previously submitted valid study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Protection of Data Submitters' Rights § 152.93 Citation of a previously submitted valid study. An... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Citation of a previously submitted valid study. 152.93 Section 152.93 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  14. 40 CFR 152.92 - Submission of a new valid study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Protection of Data Submitters' Rights § 152.92 Submission of a new valid study. An applicant may demonstrate... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Submission of a new valid study. 152.92 Section 152.92 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)...

  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. Validation of Health Extension Workers Job Motivation Scale in Gamo-Gofa Zone, Southern Ethiopia: A Cross-Sectional Study.

    PubMed

    Mohammed, Shikur; Tilahun, Marelign; Kote, Mesfin; Mama, Mohamedaman; Tamiru, Dessalegn

    2015-01-01

    Introduction. Well-trained and highly motivated community health workers are critical for delivery of community-based health care services. Understanding what motivates especially community health care providers for better community health requires the use of psychometrically reliable and valid scale. This study was conducted to validate job motivation scale in Gamo Gofa Zone, Southern Ethiopia. Methods. A cross-sectional study was conducted in 150 health care posts in Gamo Gofa Zone, from February 01, 2013, to March 01, 2013. A total of 301 participants responded to questionnaires asking about sociodemographic characteristics and job motivation. Exploratory factor analysis with principal component extraction and varimax with Kaiser Normalization rotation were employed to develop scales for job motivation. Eigenvalues greater than 1 were used as criterion of extraction. Items with item factor loadings less than 0.4 and double loaded items were dropped. Alpha and exploratory factor analyses were examined to test reliability and validity of the scale. Results. During exploratory factor analysis eight factors emerged from the three dimensions of job motivation scale, namely, educational career, workload, financial incentive, supervisor encouragement, community recognition, access to infrastructure, living condition, and better achievement in work. The factor loadings of the items in each dimension ranged from 0.58 to 0.83. Crobach's alpha of the scales ranged from 0.79 to 0.90. To check validities of the scales developed in this study, the previous studies conducted to develop job motivation scale were used. Conclusion. Although the present scale has the potential to measure the job motivation of health extension workers and it is low in cost and easy to administer and analyze, it should be field-tested at different settings.

  18. Emotional Reactivity and the Emergence of Conduct Problems and Emotional Symptoms in 7- to 11-Year-Olds: A 1-Year Follow-up Study

    ERIC Educational Resources Information Center

    Sharp, Carla; Petersen, Nancy; Goodyer, Ian

    2008-01-01

    A study to investigate the relation between psychopathology and predictive validity of emotional reactivity in children over a 1-year follow up period was conducted. The investigation was done using the International Affective Picture System to determine individual differences in the emotional and attention process involved in appetitive and…

  19. A computational study of advanced exhaust system transition ducts with experimental validation

    NASA Technical Reports Server (NTRS)

    Wu, C.; Farokhi, S.; Taghavi, R.

    1992-01-01

    The current study is an application of CFD to a 'real' design and analysis environment. A subsonic, three-dimensional parabolized Navier-Stokes (PNS) code is used to construct stall margin design charts for optimum-length advanced exhaust systems' circular-to-rectangular transition ducts. Computer code validation has been conducted to examine the capability of wall static pressure predictions. The comparison of measured and computed wall static pressures indicates a reasonable accuracy of the PNS computer code results. Computations have also been conducted on 15 transition ducts, three area ratios, and five aspect ratios. The three area ratios investigated are constant area ratio of unity, moderate contracting area ratio of 0.8, and highly contracting area ratio of 0.5. The degree of mean flow acceleration is identified as a dominant parameter in establishing the minimum duct length requirement. The effect of increasing aspect ratio in the minimum length transition duct is to increase the length requirement, as well as to increase the mass-averaged total pressure losses. The design guidelines constructed from this investigation may aid in the design and manufacture of advanced exhaust systems for modern fighter aircraft.

  20. 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…

  1. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will...

  2. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will...

  3. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will...

  4. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will...

  5. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will...

  6. 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 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.

  7. 41 CFR 60-3.14 - Technical standards for validity studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... likely to affect validity differences; or that these factors are included in the design of the study and... factors likely to affect validity differences; or such factors should be included in the design of the... procedure designed to measure the work behavior may be developed specifically from the job and job...

  8. 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…

  9. 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…

  10. 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…

  11. 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…

  12. Validation Study of a Gatekeeping Attitude Index for Social Work Education

    ERIC Educational Resources Information Center

    Tam, Dora M. Y.; Coleman, Heather

    2011-01-01

    This article reports on a study designed to validate the Gatekeeping Attitude Index, a 14-item Likert scaling index. The authors collected data from a convenience sample of social work field instructors (N = 188) with a response rate of 74.0%. Construct validation by exploratory factor analysis identified a 2-factor solution on the index after…

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

    ERIC Educational Resources Information Center

    Orme, John G.; And Others

    1986-01-01

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

  14. 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…

  15. 29 CFR 1607.7 - Use of other validity studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... work behaviors, as shown by appropriate job analyses both on the job or group of jobs on which the...) Fairness evidence. The studies include a study of test fairness for each race, sex, and ethnic group...

  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. A study of the influence of conductive paths and their directions in randomly generated conductor network.

    NASA Astrophysics Data System (ADS)

    Mandolesi, E.; Moorkamp, M.; Jones, A. G.

    2014-12-01

    Most electromagnetic (EM) geophysical methods focus on the electrical conductivity of rocks and sediments to determine the geological structure of the subsurface. Electric conductivity itself is measured in the laboratory with a wide range of instruments and techniques. These measurements seldom return a compatible result. The presence of partially-interconnected random pathways of electrically conductive materials in resistive hosts has been studied for decades, and recently with increasing interest. To comprehend which conductive mechanism scales from the microstructures up to field electrical conductivity measurements, two main branch of studies have been undertaken: statistical probability of having a conductive pathways and mixing laws. Several numerical approaches have been tested to understand the effects of interconnected pathways of conductors at field scale. Usually these studies were restricted in two ways: the sources are considered constant in time (i.e., DC) and the domain is, with few exception, two-dimensional. We simulated the effects of time-varying EM sources on the conductivity measured on the surface of a three-dimensional randomly generated body embedded in an uniform host by using electromagnetic induction equations. We modelled a two-phase mixture of resistive and conductive elements with the goal of comparing the conductivity measured on field scale with the one proper of the elements constituting the random rock, and to test how the internal structures influence the directionality of the responses. Moreover, we modelled data from randomly generated bodies characterized by coherent internal structures, to check the effect of the named structures on the anisotropy of the effective conductivity. We compared these values with the electrical conductivity limits predicted by Hashin-Shtrikman bounds and the effective conductivity predicted by the Archie's law, both cast in its classic form and in an updated that allow to take in account two

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

    SciTech Connect

    Abiddin, Jamal Farghali Bin Zainal; Ahmad, Azizah Hanom

    2015-08-28

    Sodium ion (Na{sup +}) 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{sup +} 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{sup −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{sup −5} S/cm.

  19. 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.

  20. 29 CFR 1607.14 - Technical standards for validity studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... service. A standardized rating of overall work performance may be used where a study of the job shows that.... Standards regarding investigation of possible bias in testing. An investigation of fairness of a...

  1. 29 CFR 1607.14 - Technical standards for validity studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... service. A standardized rating of overall work performance may be used where a study of the job shows that.... Standards regarding investigation of possible bias in testing. An investigation of fairness of a...

  2. Occupational exposure to pesticides and nerve conduction studies among Korean farmers.

    PubMed

    Park, Su Kyeong; Kong, Kyoung Ae; Cha, Eun Shil; Lee, Young Joo; Lee, Gyu Taek; Lee, Won Jin

    2012-01-01

    This study aimed to determine whether occupational exposure to pesticides was associated with decreased nerve conduction studies among farmers. On 2 separate occasions, the authors performed a cross-sectional study of a group of 31 male farmers who periodically applied pesticides. The study included questionnaire interviews and nerve conduction studies on the median, ulnar, posterior tibial, peroneal, and sural nerves. Although all mean values remained within laboratory normal limits, significant differences between the first and second tests were found in sensory conduction velocities on the median and sural nerves, and motor conduction velocities on the posterior tibial nerve. Lifetime days of pesticide application was negatively associated with nerve conduction velocities at most nerves after adjusting for potential confounders. These findings may reflect a link between occupational pesticide exposure and peripheral neurophysiologic abnormality that deserves further evaluation.

  3. 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

  4. Glycosylated Conductive Polymer: A Multimodal Biointerface for Studying Carbohydrate-Protein Interactions.

    PubMed

    Zeng, Xiangqun; Qu, Ke; Rehman, Abdul

    2016-09-20

    polymerization but also enable the simultaneous analysis of the binding events with orthogonal electrical, optical, or mass sensing label-free readouts. We established this approach using polyaniline and polythiophene as examples. Two general methods were demonstrated for glycosylated polymer fabrications (i.e., electropolymerization of monomer bearing α-mannoside residues or click chemistry based mannose conjugation to electrochemically preformed quinone fused polymer with potential to introduce different carbohydrate moieties and construct glycan arrays in a similar manner). Their conjugated π system extending over a large number of recurrent monomer units renders them sensitive optoelectronic materials. The carbohydrate-protein interactions on the side chain could disrupt the electrostatic, H-bonding, steric, or van der Waals interactions within or between polymers, leading to a change of conductivity or optical absorption of the conductive polymers. This will allow concurrent interrogation of these interactions with adjoining biological processes and mechanisms in multimodal fashion. Furthermore, the functionalized glycosylated conductive polymers can be designed and synthesized with controlled oxidation states, desired ionic dopants, and the imperative density and orientation of the sugar ligands that enable the assessment of differential receptor binding profiles of carbohydrate-protein interactions with much more detailed information and high accuracy. Finally, the glycosylated biosensing interfaces were successfully validated for their applications in Gram-negative bacterial detection, antibiotic resistance studies, and antimicrobial susceptibility assays, all based on inferring carbohydrate-protein interactions directly on cell surfaces, thus illustrating their potential uses in infectious disease research, clinical diagnostics, and environmental monitoring of harmful pathogens.

  5. Glycosylated Conductive Polymer: A Multimodal Biointerface for Studying Carbohydrate-Protein Interactions.

    PubMed

    Zeng, Xiangqun; Qu, Ke; Rehman, Abdul

    2016-09-20

    polymerization but also enable the simultaneous analysis of the binding events with orthogonal electrical, optical, or mass sensing label-free readouts. We established this approach using polyaniline and polythiophene as examples. Two general methods were demonstrated for glycosylated polymer fabrications (i.e., electropolymerization of monomer bearing α-mannoside residues or click chemistry based mannose conjugation to electrochemically preformed quinone fused polymer with potential to introduce different carbohydrate moieties and construct glycan arrays in a similar manner). Their conjugated π system extending over a large number of recurrent monomer units renders them sensitive optoelectronic materials. The carbohydrate-protein interactions on the side chain could disrupt the electrostatic, H-bonding, steric, or van der Waals interactions within or between polymers, leading to a change of conductivity or optical absorption of the conductive polymers. This will allow concurrent interrogation of these interactions with adjoining biological processes and mechanisms in multimodal fashion. Furthermore, the functionalized glycosylated conductive polymers can be designed and synthesized with controlled oxidation states, desired ionic dopants, and the imperative density and orientation of the sugar ligands that enable the assessment of differential receptor binding profiles of carbohydrate-protein interactions with much more detailed information and high accuracy. Finally, the glycosylated biosensing interfaces were successfully validated for their applications in Gram-negative bacterial detection, antibiotic resistance studies, and antimicrobial susceptibility assays, all based on inferring carbohydrate-protein interactions directly on cell surfaces, thus illustrating their potential uses in infectious disease research, clinical diagnostics, and environmental monitoring of harmful pathogens. PMID:27524389

  6. 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...

  7. 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...

  8. Measuring suicidality using the personality assessment inventory: a convergent validity study with federal inmates.

    PubMed

    Patry, Marc W; Magaletta, Philip R

    2015-02-01

    Although numerous studies have examined the psychometric properties and clinical utility of the Personality Assessment Inventory in correctional contexts, only two studies to date have specifically focused on suicide ideation. This article examines the convergent validity of the Suicide Ideation Scale and the Suicide Potential Index on the Personality Assessment Inventory in a large, nontreatment sample of male and female federal inmates (N = 1,120). The data indicated robust validity support for both the Suicide Ideation Scale and Suicide Potential Index, which were each correlated with a broad group of validity indices representing multiple assessment modalities. Recommendations for future research to build upon these findings through replication and extension are made.

  9. A Validation Study of the Youth Development Assessment Device

    ERIC Educational Resources Information Center

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

    2009-01-01

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

  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. 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…

  15. A Validity Study: Attitudes towards Statistics among Japanese College Students

    ERIC Educational Resources Information Center

    Satake, Eike

    2015-01-01

    This cross-cultural study investigated the relationship between attitudes toward statistics (ATS) and course achievement (CA) among Japanese college students. The sample consisted of 135 male and 134 female students from the first two-year liberal arts program of a four-year college in Tokyo, Japan. Attitudes about statistics were measured using…

  16. Attitude Patterns and the Production of Original Verbal Images: A Study in Construct Validity

    ERIC Educational Resources Information Center

    Khatena, Joe; Torrance, E. Paul

    1971-01-01

    The Runner Studies of Attitude Patterns, a personality inventory, was used as the criterion to determine construct validity of Sounds and Images and Onomatopoeia and Images, two tests of verbal originality. (KW)

  17. Generalization of GRE General Test Validity across Departments.

    ERIC Educational Resources Information Center

    Boldt, Robert F.

    This study of the validity of the Graduate Record Examinations (GRE) General Test used data from predictive validity studies that were conducted by the GRE Validity Study Service (VSS) in 79 graduate departments. The performance criterion was first-year grades in graduate school. Observed validities were computed, and for each graduate department…

  18. Human factors validation study of 3 mg sumatriptan autoinjector, for migraine patients

    PubMed Central

    Brand-Schieber, Elimor; Munjal, Sagar; Kumar, Rajesh; Andre, Anthony D; Valladao, Will; Ramirez, Margarita

    2016-01-01

    Background Migraine pain relief is reported by more than 50% of patients who receive low dose (3 mg) of sumatriptan. Currently, there is no two-step autoinjector of low-dose sumatriptan available on the market for acute migraine treatment. To fulfill this need, a fully assembled, single-dose, subcutaneous autoinjector (sumatriptan 3 mg; product-code DFN-11) was developed. The device allows for injection with a simple two-step, push-to-inject process and provides feedback of the injection activation, progress, and completion. Objective To determine if DFN-11 autoinjector can be used correctly and safely by migraine patients. Methods and participants A human factors validation study was conducted with 45 migraine patients (30 oral-only medications users; 15 injectable sumatriptan users) who performed one unaided simulated injection. Two days prior, half the oral participants were briefly trained. All others were only given the device to inspect and written instructions to review. No injections were performed during the initial session. All participants received written instructions at the injection session. Results All participants (45/45; 100%) performed the injection without any errors. Objective measures included device removal from packaging, cap removal, expiration date check, inspection of fluid in window, identification of allowable injection site, proper device positioning, dose confirmation, and device disposal. All participants (45/45; 100%) reported no difficulty administering the injection and no concerns about using the autoinjector during a severe migraine onset. Conclusion The results showed that the DFN-11 autoinjector can be used with safe handling without patterns of confusion, failures, high-risk errors, wet injections, or patient safety risks. The DFN-11 autoinjector was validated to be used correctly and safely by migraine patients, whether they were injection experienced, unexperienced, trained, or self-trained. PMID:27313479

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

    PubMed

    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.

  20. 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.

  1. 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

  2. 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

  3. An Arabic version of the effort-reward imbalance questionnaire: translation and validation study.

    PubMed

    Almadi, Tawfiq; Cathers, Ian; Chow, Chin Moi

    2013-08-01

    An Arabic version of the Effort-Reward Imbalance Questionnaire was developed and validated through a translation process with cross-cultural considerations. The translated questionnaire was evaluated for reliability and validity. A Principal Components Analysis was conducted following assessment of the suitability of data for factor analysis. Components with high eigenvalues were extracted, followed by Varimax rotation. Three components with eigenvalues greater than 1.0 (50% of variance) were indicated. The analysis showed Cronbach's alpha coefficients of .82 for the Effort scale, .88 for the Reward scale, and .74 for the Overcommitment scale. The test-retest reliability was high with intra-correlation coefficients of > or = .86. The Arabic version of the Effort-Reward Imbalance Questionnaire showed adequate reliability and validity and is a suitable instrument to assess work stress in Arabic-speaking people.

  4. 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

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

    PubMed

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

    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

  6. 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.

  7. A study of the reliability and comparative validity of the cardia dietary history.

    PubMed

    Liu, K; Slattery, M; Jacobs, D; Cutter, G; McDonald, A; Van Horn, L; Hilner, J E; Caan, B; Bragg, C; Dyer, A

    1994-01-01

    This study evaluated the reliability and comparative validity of the dietary history survey method developed for CARDIA, a longitudinal investigation of life-styles and the evolution of cardiovascular risk factors in young adults. The method was tested in a sample of 30 white men, 33 white women, 33 black men, and 32 black women, aged 18 to 35 years, in four regions reflecting the race, sex, age, and geographical distribution of CARDIA participants. For 64 of the participants, two dietary history interviews, 1 month apart, were conducted by trained nutritionists. These data were used to examine the reliability of the method. For all participants, seven telephone- assessed 24-hour dietary recalls were randomly scheduled during a 28-day period and were followed by a dietary history interview. These data were used to examine the comparative validity of the method. Calories, total fat, saturated fat, polyunsaturated fat, monounsaturated fat, dietary cholesterol, protein, carbohydrate, alcohol, potassium, calcium, and vitamin A were selected by the CARDIA Nutrition Working Group as the nutrients for comparison. Mean nutrient values from the first history tended to be higher than those obtained from the last history. However, for a majority of the nutrients, the differences were significant for blacks but not for whites. The correlations for the log-transformed nutrient values and calorie-adjusted nutrient values from the two histories were generally in the range of 0.50 to 0.80 for whites. For blacks, the correlations were lower, with a majority in the range of 0.30 to 0.70. The average nutrient values estimated from the histories were higher than those estimated from the average of the seven 24-hour recalls. The differences in blacks were larger than in whites. For both the log-transformed nutrient values and the calorie-adjusted nutrient values, the correlations between the two methods were generally larger than 0.50 for whites. However, for blacks, the correlations

  8. "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…

  9. Experimental study of critical exponents of electrical conductivity in a two-dimensional continuum percolation system

    PubMed

    Okazaki; Horibe; Maruyama; Miyazima

    2000-06-01

    In this paper an experimental study is presented for critical exponents of electrical conductivity in an inverse Swiss-cheese model. Filled circles are drawn on random positions of square paper in drawing ink with an X-Y plotter, and electrical resistance between both opposite sides is measured automatically by the use of general purpose interface bus system. Electrical conductivity is obtained from the inverse of the electrical resistance. Electrical conductivity in a bond process is also measured with the same system. It is confirmed that the critical exponent of electrical conductivity of a continuum two-dimensional inverse Swiss-cheese model is different from that of a discrete one.

  10. 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…

  11. Validation of a virtual preoperative evaluation clinic: a pilot study.

    PubMed

    Zetterman, Corey V; Sweitzer, Bobbie J; Webb, Brad; Barak-Bernhagen, Mary A; Boedeker, Ben H

    2011-01-01

    Patients scheduled for surgery at the Omaha VA Medical Center were evaluated preoperatively via telemedicine. Following the examination, patients filled out a 15 item, 5 point Likert scale questionnaire regarding their opinion of preoperative evaluation in a VTC format. Evaluations were performed under the direction of nationally recognized guidelines and recommendations of experts in the field of perioperative medicine and were overseen by a staff anesthesiologist from the Omaha VA Medical Center. No significant difficulties were encountered by the patient or the evaluator regarding the quality of the audio/visual capabilities of the VTC link and its ability to facilitate preoperative evaluation. 87.5% of patients felt that virtual evaluation would save them travel time; 87.5% felt virtual evaluation could save them money; 7.3% felt uncomfortable using the VTC link; 12.2% felt the virtual evaluation took longer than expected; 70.7% preferred to be evaluated via VTC link; 21.9% were undecided; 9.7% felt they would rather be evaluated face-to-face with 26.8% undecided; 85.0% felt that teleconsultation was as good as being seen at the Omaha surgical evaluation unit; 7.5% were undecided. Our study has shown that effective preoperative evaluation can be performed using a virtual preoperative evaluation clinic; patients are receptive to the VTC format and, in the majority of cases, prefer it to face-to-face evaluation.

  12. An external construct validity study of Rorschach personality variables.

    PubMed

    Greenwald, D F

    1990-01-01

    This study examined (a) hypothesized relationships between Rorschach variables and self-report test measures relating to nominally similar aspects of personality functioning and (b) interrelationships among Rorschach variables. Sixty-two undergraduates were administered the Rorschach, Barron Ego Strength Scale, Kaplan Self-Derogation Scale, Eagly Self-Esteem Scale, Multiple Affective Adjective Checklist (MAACL), Marlowe-Crowne Social Desirability Scale, and the Rotter Locus of Control Scale. Only a few of the predictions received confirmation: inanimate movement (m) correlated, as expected, with MAACL anxiety and hostility, the egocentricity index (3r + 2)/R (R = total responses) correlated significantly with self-esteem, and human movement with minus form level (M-) correlated (inversely) with ego strength. Among the unpredicted findings were some that appear inconsistent with standard Rorschach interpretation. Rorschach variables human movement (M), and experience actual (EA), generally interpreted as reflecting coping resources, related significantly with self-report measures of poor coping and of dysphoric affect. In general, the Rorschach appears better at identifying weaknesses in the ego rather than strengths. PMID:2280339

  13. Multicentre validation study of nucleic acids extraction from FFPE tissues.

    PubMed

    Bonin, Serena; Hlubek, Falk; Benhattar, Jean; Denkert, Carsten; Dietel, Manfred; Fernandez, Pedro L; Höfler, Gerald; Kothmaier, Hannelore; Kruslin, Bozo; Mazzanti, Chiara Maria; Perren, Aurel; Popper, Helmuth; Scarpa, Aldo; Soares, Paula; Stanta, Giorgio; Groenen, Patricia J T A

    2010-09-01

    In most pathology laboratories worldwide, formalin-fixed paraffin embedded (FFPE) samples are the only tissue specimens available for routine diagnostics. Although commercial kits for diagnostic molecular pathology testing are becoming available, most of the current diagnostic tests are laboratory-based assays. Thus, there is a need for standardized procedures in molecular pathology, starting from the extraction of nucleic acids. To evaluate the current methods for extracting nucleic acids from FFPE tissues, 13 European laboratories, participating to the European FP6 program IMPACTS (www.impactsnetwork.eu), isolated nucleic acids from four diagnostic FFPE tissues using their routine methods, followed by quality assessment. The DNA-extraction protocols ranged from homemade protocols to commercial kits. Except for one homemade protocol, the majority gave comparable results in terms of the quality of the extracted DNA measured by the ability to amplify differently sized control gene fragments by PCR. For array-applications or tests that require an accurately determined DNA-input, we recommend using silica based adsorption columns for DNA recovery. For RNA extractions, the best results were obtained using chromatography column based commercial kits, which resulted in the highest quantity and best assayable RNA. Quality testing using RT-PCR gave successful amplification of 200 bp-250 bp PCR products from most tested tissues. Modifications of the proteinase-K digestion time led to better results, even when commercial kits were applied. The results of the study emphasize the need for quality control of the nucleic acid extracts with standardised methods to prevent false negative results and to allow data comparison among different diagnostic laboratories.

  14. 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

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

    NASA Astrophysics Data System (ADS)

    Petersen, Walt; Krajewski, Witold

    2013-04-01

    The overarching objective of integrated hydrologic ground validation activities supporting the Global Precipitation Measurement Mission (GPM) is to provide better understanding of the strengths and limitations of the satellite products, in the context of hydrologic applications. To this end, the GPM Ground Validation (GV) program is conducting the first of several hydrology-oriented field efforts: the Iowa Flood Studies (IFloodS) experiment. IFloodS will be conducted in the central to northeastern part of Iowa in Midwestern United States during the months of April-June, 2013. Specific science objectives and related goals for the IFloodS experiment can be summarized as follows: 1. Quantify the physical characteristics and space/time variability of rain (rates, DSD, process/"regime") and map to satellite rainfall retrieval uncertainty. 2. Assess satellite rainfall retrieval uncertainties at instantaneous to daily time scales and evaluate propagation/impact of uncertainty in flood-prediction. 3. Assess hydrologic predictive skill as a function of space/time scales, basin morphology, and land use/cover. 4. Discern the relative roles of rainfall quantities such as rate and accumulation as compared to other factors (e.g. transport of water in the drainage network) in flood genesis. 5. Refine approaches to "integrated hydrologic GV" concept based on IFloodS experiences and apply to future GPM Integrated GV field efforts. These objectives will be achieved via the deployment of the NASA NPOL S-band and D3R Ka/Ku-band dual-polarimetric radars, University of Iowa X-band dual-polarimetric radars, a large network of paired rain gauge platforms with attendant soil moisture and temperature probes, a large network of both 2D Video and Parsivel disdrometers, and USDA-ARS gauge and soil-moisture measurements (in collaboration with the NASA SMAP mission). The aforementioned measurements will be used to complement existing operational WSR-88D S-band polarimetric radar measurements

  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. 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…

  18. Clinical audit project in undergraduate medical education curriculum: an assessment validation study

    PubMed Central

    Steketee, Carole; Mak, Donna

    2016-01-01

    Objectives To evaluate the merit of the Clinical Audit Project (CAP) in an assessment program for undergraduate medical education using a systematic assessment validation framework. Methods A cross-sectional assessment validation study at one medical school in Western Australia, with retrospective qualitative analysis of the design, development, implementation and outcomes of the CAP, and quantitative analysis of assessment data from four cohorts of medical students (2011- 2014). Results The CAP is fit for purpose with clear external and internal alignment to expected medical graduate outcomes.  Substantive validity in students’ and examiners’ response processes is ensured through relevant methodological and cognitive processes. Multiple validity features are built-in to the design, planning and implementation process of the CAP.  There is evidence of high internal consistency reliability of CAP scores (Cronbach’s alpha > 0.8) and inter-examiner consistency reliability (intra-class correlation>0.7). Aggregation of CAP scores is psychometrically sound, with high internal consistency indicating one common underlying construct.  Significant but moderate correlations between CAP scores and scores from other assessment modalities indicate validity of extrapolation and alignment between the CAP and the overall target outcomes of medical graduates.  Standard setting, score equating and fair decision rules justify consequential validity of CAP scores interpretation and use. Conclusions This study provides evidence demonstrating that the CAP is a meaningful and valid component in the assessment program. This systematic framework of validation can be adopted for all levels of assessment in medical education, from individual assessment modality, to the validation of an assessment program as a whole.  PMID:27716612

  19. 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

  20. 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.

  1. Validation of hydraulic tomography in an unconfined aquifer: A controlled sandbox study

    NASA Astrophysics Data System (ADS)

    Zhao, Zhanfeng; Illman, Walter A.; Yeh, Tian-Chyi J.; Berg, Steven J.; Mao, Deqiang

    2015-06-01

    In this study, we demonstrate the effectiveness of hydraulic tomography (HT) that considers variably saturated flow processes in mapping the heterogeneity of both the saturated and unsaturated zones in a laboratory unconfined aquifer. The successive linear estimator (SLE) developed by Mao et al. (2013c) for interpreting HT in unconfined aquifers is utilized to obtain tomograms of hydraulic conductivity (K), specific storage (Ss), and the unsaturated zone parameters (pore size parameter (α) and saturated water content (θs)) for the Gardner-Russo's model. The estimated tomograms are first evaluated by visually comparing them with stratigraphy visible in the sandbox. Results reveal that the HT analysis is able to accurately capture the location and extent of heterogeneity including high and low K layers within the saturated and unsaturated zones, as well as reasonable distribution patterns of α and θs for the Gardner-Russo's model. We then validate the estimated tomograms through predictions of drawdown responses of pumping tests not used during the inverse modeling effort. The strong agreement between simulated and observed drawdown curves obtained by pressure transducers and tensiometers demonstrates the robust performance of HT that considers variably saturated flow processes in unconfined aquifers and the unsaturated zone above it. In addition, compared to the case using the homogeneous assumption, HT results, as expected, yield significantly better predictions of drawdowns in both the saturated and unsaturated zones. This comparison further substantiates the unbiased and minimal variance of HT analysis with the SLE algorithm.

  2. Terrestrial gastropods (Helix spp) as sentinels of primary DNA damage for biomonitoring purposes: a validation study.

    PubMed

    Angeletti, Dario; Sebbio, Claudia; Carere, Claudio; Cimmaruta, Roberta; Nascetti, Giuseppe; Pepe, Gaetano; Mosesso, Pasquale

    2013-04-01

    We validated the alkaline comet assay in two species of land snail (Helix aspersa and Helix vermiculata) to test their suitability as sentinels for primary DNA damage in polluted environments. The study was conducted under the framework of a biomonitoring program for a power station in Central Italy that had recently been converted from oil to coal-fired plant. After optimizing test conditions, the comet assay was used to measure the % Tail DNA induced by in vitro exposure of hemocytes to different concentrations of a reactive oxygen species (H2 O2 ). The treatment induced significant increases in this parameter with a concentration effect, indicating the effectiveness of the assay in snail hemocytes. After evaluating possible differences between the two species, we sampled them in three field sites at different distances from the power station, and in two reference sites assumed to have low or no levels of pollution. No species differences emerged. Percent Tail DNA values in snails from the sites near the power station were higher than those from control sites. An inverse correlation emerged between % Tail DNA and distance from the power station, suggesting that the primary DNA damage decreased as distance increased away from the pollution source. Detection of a gradient of heavy metal concentration in snail tissues suggests that these pollutants are a potential cause of the observed pattern. The comet assay appears to be a suitable assay and Helix spp. populations suitable sentinels to detect the genotoxic impact of pollutants. PMID:23444166

  3. Terrestrial gastropods (Helix spp) as sentinels of primary DNA damage for biomonitoring purposes: a validation study.

    PubMed

    Angeletti, Dario; Sebbio, Claudia; Carere, Claudio; Cimmaruta, Roberta; Nascetti, Giuseppe; Pepe, Gaetano; Mosesso, Pasquale

    2013-04-01

    We validated the alkaline comet assay in two species of land snail (Helix aspersa and Helix vermiculata) to test their suitability as sentinels for primary DNA damage in polluted environments. The study was conducted under the framework of a biomonitoring program for a power station in Central Italy that had recently been converted from oil to coal-fired plant. After optimizing test conditions, the comet assay was used to measure the % Tail DNA induced by in vitro exposure of hemocytes to different concentrations of a reactive oxygen species (H2 O2 ). The treatment induced significant increases in this parameter with a concentration effect, indicating the effectiveness of the assay in snail hemocytes. After evaluating possible differences between the two species, we sampled them in three field sites at different distances from the power station, and in two reference sites assumed to have low or no levels of pollution. No species differences emerged. Percent Tail DNA values in snails from the sites near the power station were higher than those from control sites. An inverse correlation emerged between % Tail DNA and distance from the power station, suggesting that the primary DNA damage decreased as distance increased away from the pollution source. Detection of a gradient of heavy metal concentration in snail tissues suggests that these pollutants are a potential cause of the observed pattern. The comet assay appears to be a suitable assay and Helix spp. populations suitable sentinels to detect the genotoxic impact of pollutants.

  4. 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.

  5. Do placebo based validation standards mimic real batch products behaviour? Case studies.

    PubMed

    Bouabidi, A; Talbi, M; Bouklouze, A; El Karbane, M; Bourichi, H; El Guezzar, M; Ziemons, E; Hubert, Ph; Rozet, E

    2011-06-01

    Analytical methods validation is a mandatory step to evaluate the ability of developed methods to provide accurate results for their routine application. Validation usually involves validation standards or quality control samples that are prepared in placebo or reconstituted matrix made of a mixture of all the ingredients composing the drug product except the active substance or the analyte under investigation. However, one of the main concerns that can be made with this approach is that it may lack an important source of variability that come from the manufacturing process. The question that remains at the end of the validation step is about the transferability of the quantitative performance from validation standards to real authentic drug product samples. In this work, this topic is investigated through three case studies. Three analytical methods were validated using the commonly spiked placebo validation standards at several concentration levels as well as using samples coming from authentic batch samples (tablets and syrups). The results showed that, depending on the type of response function used as calibration curve, there were various degrees of differences in the results accuracy obtained with the two types of samples. Nonetheless the use of spiked placebo validation standards was showed to mimic relatively well the quantitative behaviour of the analytical methods with authentic batch samples. Adding these authentic batch samples into the validation design may help the analyst to select and confirm the most fit for purpose calibration curve and thus increase the accuracy and reliability of the results generated by the method in routine application. PMID:21377822

  6. 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

  7. 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.

  8. 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

  9. 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…

  10. Construction and Validation of a Questionnaire to Study Future Teachers' Beliefs about Cultural Diversity

    ERIC Educational Resources Information Center

    López López, M. Carmen; Hinojosa Pareja, Eva F.

    2016-01-01

    The article presents the construction and validation process of a questionnaire designed to study student teachers' beliefs about cultural diversity. The study, beyond highlighting the complexity involved in the study of beliefs, emphasises their relevance in implementing inclusive educational processes that guarantee the right to a good education…

  11. Diameter Dependence of Lattice Thermal Conductivity of Single-Walled Carbon Nanotubes: Study from Ab Initio.

    PubMed

    Yue, Sheng-Ying; Ouyang, Tao; Hu, Ming

    2015-10-22

    The effects of temperature, tube length, defects, and surface functionalization on the thermal conductivity (κ) of single-walled carbon nanotubes (SWCNTs) were well documented in literature. However, diameter dependence of thermal conductivity of SWCNTs received less attentions. So far, diverse trends of the diameter dependence have been discussed by different methods and all the previous results were based on empirical interatomic potentials. In this paper, we emphasize to clarify accurate κ values of SWCNTs with different diameters and in-plane κ of graphene. All the studies were under the framework of anharmonic lattice dynamics and Boltzmann transport equation (BTE) based on first principle calculations. We try to infer the right trend of diameter dependent thermal conductivity of SWCNTs. We infer that graphene is the limitation as SWCNT with an infinite diameter. We analyzed the thermal conductivity contributions from each phonon mode in SWCNTs to explain the trend. Meanwhile, we also identify the extremely low thermal conductivity of ultra-thin SWCNTs.

  12. 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.

  13. 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.

  14. 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.

  15. A HTML5 open source tool to conduct studies based on Libet’s clock paradigm

    PubMed Central

    Garaizar, Pablo; Cubillas, Carmelo P.; Matute, Helena

    2016-01-01

    Libet’s clock is a well-known procedure in experiments in psychology and neuroscience. Examples of its use include experiments exploring the subjective sense of agency, action-effect binding, and subjective timing of conscious decisions and perceptions. However, the technical details of the apparatus used to conduct these types of experiments are complex, and are rarely explained in sufficient detail as to guarantee an exact replication of the procedure. With this in mind, we developed Labclock Web, a web tool designed to conduct online and offline experiments using Libet’s clock. After describing its technical features, we explain how to configure specific experiments using this tool. Its degree of accuracy and precision in the presentation of stimuli has been technically validated, including the use of two cognitive experiments conducted with voluntary participants who performed the experiment both in our laboratory and via the Internet. Labclock Web is distributed without charge under a free software license (GPLv3) since one of our main objectives is to facilitate the replication of experiments and hence the advancement of knowledge in this area. PMID:27623167

  16. A HTML5 open source tool to conduct studies based on Libet's clock paradigm.

    PubMed

    Garaizar, Pablo; Cubillas, Carmelo P; Matute, Helena

    2016-01-01

    Libet's clock is a well-known procedure in experiments in psychology and neuroscience. Examples of its use include experiments exploring the subjective sense of agency, action-effect binding, and subjective timing of conscious decisions and perceptions. However, the technical details of the apparatus used to conduct these types of experiments are complex, and are rarely explained in sufficient detail as to guarantee an exact replication of the procedure. With this in mind, we developed Labclock Web, a web tool designed to conduct online and offline experiments using Libet's clock. After describing its technical features, we explain how to configure specific experiments using this tool. Its degree of accuracy and precision in the presentation of stimuli has been technically validated, including the use of two cognitive experiments conducted with voluntary participants who performed the experiment both in our laboratory and via the Internet. Labclock Web is distributed without charge under a free software license (GPLv3) since one of our main objectives is to facilitate the replication of experiments and hence the advancement of knowledge in this area. PMID:27623167

  17. A HTML5 open source tool to conduct studies based on Libet's clock paradigm.

    PubMed

    Garaizar, Pablo; Cubillas, Carmelo P; Matute, Helena

    2016-09-13

    Libet's clock is a well-known procedure in experiments in psychology and neuroscience. Examples of its use include experiments exploring the subjective sense of agency, action-effect binding, and subjective timing of conscious decisions and perceptions. However, the technical details of the apparatus used to conduct these types of experiments are complex, and are rarely explained in sufficient detail as to guarantee an exact replication of the procedure. With this in mind, we developed Labclock Web, a web tool designed to conduct online and offline experiments using Libet's clock. After describing its technical features, we explain how to configure specific experiments using this tool. Its degree of accuracy and precision in the presentation of stimuli has been technically validated, including the use of two cognitive experiments conducted with voluntary participants who performed the experiment both in our laboratory and via the Internet. Labclock Web is distributed without charge under a free software license (GPLv3) since one of our main objectives is to facilitate the replication of experiments and hence the advancement of knowledge in this area.

  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. 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…

  1. 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

  2. A New Cuffless Device for Measuring Blood Pressure: A Real-Life Validation Study

    PubMed Central

    Schoot, Tessa S; Weenk, Mariska; van de Belt, Tom H; Engelen, Lucien JLPG; van Goor, Harry

    2016-01-01

    Background Cuffless blood pressure (BP) monitoring devices, based on pulse transit time, are being developed as an easy-to-use, more convenient, fast, and relatively cheap alternative to conventional BP measuring devices based on cuff occlusion. Thereby they may provide a great alternative to BP self-measurement. Objective The objective of our study was to evaluate the performance of the first release of the Checkme Health Monitor (Viatom Technology), a cuffless BP monitor, in a real-life setting. Furthermore, we wanted to investigate whether the posture of the volunteer and the position of the device relative to the heart level would influence its outcomes. Methods Study volunteers fell into 3 BP ranges: high (>160 mmHg), normal (130–160 mmHg), and low (<130 mmHg). All requirements for test environment, observer qualification, volunteer recruitment, and BP measurements were met according to the European Society of Hypertension International Protocol (ESH-IP) for the validation of BP measurement devices. After calibrating the Checkme device, we measured systolic BP with Checkme and a validated, oscillometric reference BP monitor (RM). Measurements were performed in randomized order both in supine and in sitting position, and with Checkme at and above heart level. Results We recruited 52 volunteers, of whom we excluded 15 (12 due to calibration failure with Checkme, 3 due to a variety of reasons). The remaining 37 volunteers were divided into low (n=14), medium (n=13), and high (n=10) BP ranges. There were 18 men and 19 women, with a mean age of 54.1 (SD 14.5) years, and mean recruitment systolic BP of 141.7 (SD 24.7) mmHg. BP results obtained by RM and Checkme correlated well. In the supine position, the difference between the RM and Checkme was >5 mmHg in 17 of 37 volunteers (46%), of whom 9 of 37 (24%) had a difference >10 mmHg and 5 of 37 (14%) had a difference >15 mmHg. Conclusions BP obtained with Checkme correlated well with RM BP, particularly in the

  3. 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.

  4. Ethical problems in conducting research in acute epidemics: the Pfizer meningitis study in Nigeria as an illustration.

    PubMed

    Ezeome, Emmanuel R; Simon, Christian

    2010-04-01

    The ethics of conducting research in epidemic situations have yet to account fully for differences in the proportion and acuteness of epidemics, among other factors. While epidemics most often arise from infectious diseases, not all infectious diseases are of epidemic proportions, and not all epidemics occur acutely. These and other variations constrain the generalization of ethical decision-making and impose ethical demands on the individual researcher in a way not previously highlighted. This paper discusses a number of such constraints and impositions. It applies the ethical principles enunciated by Emmanuel et al.(1) to the controversial Pfizer study in Nigeria in order to highlight the particular ethical concerns of acute epidemic research, and suggest ways of meeting such challenges. The paper recommends that research during epidemics should be partly evaluated on its own merits in order to determine its ethical appropriateness to the specific situation. Snap decisions to conduct research during acute epidemics should be resisted. Community engagement, public notification and good information management are needed to promote the ethics of conducting research during acute epidemics. Individual consent is most at risk of being compromised, and every effort should be made to ensure that it is maintained and valid. Use of data safety management boards should be routine. Acute epidemics also present opportunities to enhance the social value of research and maximize its benefits to communities. Ethical research is possible in acute epidemics, if the potential challenges are thought of ahead of time and appropriate precautions taken.

  5. 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

  6. Conductivity studies of Chitosan doped with different ammonium salts: Effect of ion size

    NASA Astrophysics Data System (ADS)

    Mohan, C. Raja; Senthilkumar, M.; Jayakumar, K.

    2015-06-01

    In the present investigation influence of ion size on the electrical properties of various ammonium salts of various concentrations doped with Chitosan liquid electrolyte has been studied. The attachment of ammonium salts with Chitosan has been confirmed through FTIR Spectrum. Polarizability is calculated from the refractive index data. Addition of ammonium salts increases the conductivity. It is also observed that increase in ion size, increases the ionic conductivity due to increase in amorphous nature of the material. Increase in concentration leads to increase in conductivity due to the presence of more number of free ions.

  7. Validation study on the Ocular Irritection assay for eye irritation testing.

    PubMed

    Eskes, Chantra; Hoffmann, Sebastian; Facchini, Davide; Ulmer, Rich; Wang, Amy; Flego, Manuela; Vassallo, Marco; Bufo, Monica; van Vliet, Erwin; d'Abrosca, Federica; Wilt, Nathan

    2014-08-01

    Both a prospective and a retrospective validation study were undertaken to assess the suitability of the Ocular Irritection assay to discriminate ocular hazards as defined by the OECD and UN Globally Harmonized System (UN GHS) for classification. The primary focus of the study was to evaluate the usefulness of the Ocular Irritection assay to reliably discriminate chemicals not requiring classification (UN GHS non-classified), from classified chemicals (UN GHS Categories 1 and 2). Furthermore a post-hoc evaluation was carried out to evaluate the usefulness of the assay to discriminate chemicals inducing serious eye damage (UN GHS Category 1) from other classes. The prospective validation study was conducted between 2009 and 2012 following internationally agreed principles. A set of 56 coded test chemicals for which quality and/or peer-reviewed in vivo data were available were used to obtain prospective data on the assay's reliability (reproducibility within and between laboratories) and relevance (predictive capacity). The assay showed good within-laboratory variability, transferability including to a naïve laboratory, and between-laboratory concordance of classifications (82% for the discrimination of non-classified from classified chemicals, and 83% for the discrimination of Category 1 from other classes). The obtained prospective data were then combined with existing data on the Ocular Irritection collected from various sources, totaling 88 chemicals with parallel in vivo and in vitro data to obtain a comprehensive assessment of the test method performances. The enlarged dataset comprised 43 non-classified, 25 Category 2 and 20 Category 1 chemicals according to the UN GHS classification. When used for the identification of UN GHS non-classified versus classified materials (based on the existing cut-off of 12.5) the Ocular Irritection assay showed an overall a sensitivity of 93% and a specificity of 58%. An evaluation on possible reasons for misclassification

  8. Feasible Study for Multi-photon Stereolithography Method of Electro Conductive Polymer Actuator with Complex Shape

    NASA Astrophysics Data System (ADS)

    Sone, Junji; Asami, Akihisa; Yamada, Katsumi; Chen, Jun

    Recently, a soft actuator was developed using an electro-conducting polymer and an ionic conducting polymer. Moreover, stereolithography that uses a femtosecond laser was researched as a method of multiphoton-sensitized polymerization. In this study, we tried a more stable and more rapid stereolithography method for fabricating an electro-conducting polymer using a protein material. From the results of this study, we found that the method was 10 times faster when an aqueous solid that included an electro-conducting polymer, a catalyst, and gelatine was used. In addition, it was stable in that the temperature of the aqueous solid was controlled at 10 degree. We built a 3D shape using the newly developed method, and we will apply this method to a complex actuator.

  9. 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

  10. 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…

  11. 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

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

    PubMed

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

    2013-07-14

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

  13. 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…

  14. 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…

  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. 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…

  17. 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,…

  18. Validity and Usefulness in Four WIST Studies Recently Reported in the Journal

    ERIC Educational Resources Information Center

    Whitaker, Leighton C.

    1978-01-01

    Four articles that reported studies that used the Whitaker Index of Schizophrenic Thinking (WIST) were published in the "Journal of Clinical Psychology" in early 1977. These articles are reviewed by the WIST's author in terms of necessary conditions for valid and useful studies of schizophrenic thinking. (Editor)

  19. A Validity and Reliability Study of the Motivated Strategies for Learning Questionnaire

    ERIC Educational Resources Information Center

    Erturan Ilker, Gökçe; Arslan, Yunus; Demirhan, Giyasettin

    2014-01-01

    The aim of this study is to determine the validity and reliability of the Motivated Strategies for Learning Questionnaire (MSLQ) for high school students. In total, 1605 students (829 girls, 776 boys, average age = 15.67 ± 1.19) from three different high schools in the central district of Ankara voluntarily participated in the study. The MSLQ was…

  20. 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…

  1. 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…

  2. 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…

  3. A Case for Transforming the Criterion of a Predictive Validity Study

    ERIC Educational Resources Information Center

    Patterson, Brian F.; Kobrin, Jennifer L.

    2011-01-01

    This study presents a case for applying a transformation (Box and Cox, 1964) of the criterion used in predictive validity studies. The goals of the transformation were to better meet the assumptions of the linear regression model and to reduce the residual variance of fitted (i.e., predicted) values. Using data for the 2008 cohort of first-time,…

  4. 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…

  5. 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…

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

    PubMed Central

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

    2003-01-01

    Background The Hospital Anxiety and Depression Scale (HADS) is a widely used instrument to measure psychological morbidity in cancer patients. This study aimed to translate and test the reliability and validity of the Iranian version of the HADS. Methods The English language version of the HADS was translated into Persian (Iranian language) and was used in this study. The questionnaire was administered to a consecutive sample of 167 breast cancer patients and statistical analysis was performed to test the reliability and validity of the HADS. Results In general the Iranian version of the HADS was found to be acceptable to almost all patients (99%). Cronbach's alpha coefficient (to test reliability) has been found to be 0.78 for the HADS anxiety sub-scale and 0.86 for the HADS depression sub-scale. Validity as performed using known groups comparison analysis showed satisfactory results. Both anxiety and depression sub-scales discriminated well between sub-groups of patients differing in clinical status as defined by their disease stage. Conclusion This preliminary validation study of the Iranian version of the HADS proved that it is an acceptable, a reliable and valid measure of psychological distress among cancer patients. PMID:12816545

  8. 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.

  9. 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.

  10. A Derivation and Validation Study of an Early Blood Transfusion Needs Score for Severe Trauma Patients

    PubMed Central

    Wang, Hao; Umejiego, Johnbosco; Robinson, Richard D.; Schrader, Chet D.; Leuck, JoAnna; Barra, Michael; Buca, Stefan; Shedd, Andrew; Bui, Andrew; Zenarosa, Nestor R.

    2016-01-01

    Background There is no existing adequate blood transfusion needs determination tool that Emergency Medical Services (EMS) personnel can use for prehospital blood transfusion initiation. In this study, a simple and pragmatic prehospital blood transfusion needs scoring system was derived and validated. Methods Local trauma registry data were reviewed retrospectively from 2004 through 2013. Patients were randomly assigned to derivation and validation cohorts. Multivariate logistic regression was used to identify the independent approachable risks associated with early blood transfusion needs in the derivation cohort in which a scoring system was derived. Sensitivity, specificity, and area under the receiver operational characteristic (AUC) were calculated and compared using both the derivation and validation data. Results A total of 24,303 patients were included with 12,151 patients in the derivation and 12,152 patients in the validation cohorts. Age, penetrating injury, heart rate, systolic blood pressure, and Glasgow coma scale (GCS) were risks predictive of early blood transfusion needs. An early blood transfusion needs score was derived. A score > 5 indicated risk of early blood transfusion need with a sensitivity of 83% and a specificity of 80%. A sensitivity of 82% and a specificity of 80% were also found in the validation study and their AUC showed no statistically significant difference (AUC of the derivation = 0.87 versus AUC of the validation = 0.86, P > 0.05). Conclusions An early blood transfusion scoring system was derived and internally validated to predict severe trauma patients requiring blood transfusion during prehospital or initial emergency department resuscitation. PMID:27429680

  11. 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...

  12. 42 CFR 90.8 - Conduct of health assessments and health effects studies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 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...

  13. 42 CFR 90.7 - Decision to conduct health effects study.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Decision to conduct health effects study. 90.7 Section 90.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES...

  14. 42 CFR 90.8 - Conduct of health assessments and health effects studies.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 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...

  15. 42 CFR 90.7 - Decision to conduct health effects study.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Decision to conduct health effects study. 90.7 Section 90.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES...

  16. 42 CFR 90.8 - Conduct of health assessments and health effects studies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 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...

  17. 42 CFR 90.7 - Decision to conduct health effects study.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Decision to conduct health effects study. 90.7 Section 90.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES...

  18. 42 CFR 90.8 - Conduct of health assessments and health effects studies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 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...

  19. 42 CFR 90.7 - Decision to conduct health effects study.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Decision to conduct health effects study. 90.7 Section 90.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES...

  20. 42 CFR 90.7 - Decision to conduct health effects study.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Decision to conduct health effects study. 90.7 Section 90.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES...

  1. 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…

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

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Miscellaneous § 312... examine data from such a study. (3) Marketing approval of a new drug based solely on foreign clinical data... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Foreign clinical studies not conducted under...

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

    ERIC Educational Resources Information Center

    Kelly, Michael P.; Moore, Tessa A.

    2011-01-01

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

  4. 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...

  5. Obstacles to Conducting Curriculum Research in Bilingual Education: A Case Study.

    ERIC Educational Resources Information Center

    Schon, Isabel; Hopkins, Kenneth D.

    The obstacles associated with conducting curricular research in school settings are discussed. A study of bilingual students in the Phoenix area demonstrated the difficulties associated with high absenteeism and drop out rates. In a study of Spanish reading materials, it proved difficult to identify schools where administrators would be willing to…

  6. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: SOLVENT EXTRACTION - 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 Liabi...

  7. The conductive properties of single DNA molecules studied by torsion tunneling atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Wang, W.; Niu, D. X.; Jiang, C. R.; Yang, X. J.

    2014-01-01

    The conductive properties of single natural λ-DNA molecules are studied by torsion tunneling atomic force microscopy (TR-TUNA). The currents both parallel to and perpendicular to the DNA chains are investigated, but only weak or even no current signals are detected by TR-TUNA. To improve the conductance of DNA molecules, silver and copper metallized DNAs are fabricated and their conductivities are checked by TR-TUNA. It is found that for both Cu- and Ag-DNAs, the conductivity perpendicular to the DNA chain is enhanced significantly as the metal clusters are attached to the DNA chains. But parallel to the chain the electrical transport is still weak, most probably due to the ‘beads-on-a-string’ constructions of metallized DNAs.

  8. AC Conductivity Studies in Lithium-Borate Glass Containing Gold Nanoparticles

    NASA Astrophysics Data System (ADS)

    Shivaprakash, Y.; Anavekar, R. V.

    2011-07-01

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

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

    SciTech Connect

    Jha, Neetu; Ramaprabhu, S.

    2009-10-15

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

  10. The Gambling Symptom Assessment Scale (G-SAS): a reliability and validity study.

    PubMed

    Kim, Suck Won; Grant, Jon E; Potenza, Marc N; Blanco, Carlos; Hollander, Eric

    2009-03-31

    Two hundred seven patients with DSM-IV Pathological Gambling Disorder completed both the Gambling Symptom Assessment Scale (G-SAS) and the Yale-Brown Obsessive-Compulsive Scale--modified for Pathological Gambling (PG-YBOCS) at baseline visit and weekly or biweekly thereafter during the 12-week study period. The week 1 to week 2 visit data were used to assess test-retest reliability. Weekly or biweekly data were used for the G-SAS validity. The PG-YBOCS reliability and validity data have been published previously. We used the PG-YBOCS as the established scale and compared the G-SAS performance with the PG-YBOCS. Test-retest reliability was statistically significant. The correlations between the G-SAS and the PG-YBOCS and Clinical Global Impression rating were excellent. Findings suggest that the G-SAS is reliable and valid in assessing changes in symptoms during a drug treatment study.

  11. Bioanalytical assay validation parameters re-visited: perspectives on stability studies.

    PubMed

    Srinivas, Nuggehally R

    2009-10-01

    Bioanalytical assay validation for plethora of parameters is considered vital for the reliable and accurate generation of raw analytical data used for pharmacokinetic characterization of analytes. Although the validation parameters have been widely accepted, the intent of this communication is to provide some perspectives on the commonly followed approaches for stability studies (i.e. freeze-thaw and long-term freezer stability studies). The proposed discussion is intended to stimulate the thinking process to cut down on the extra work and/or maximize the efficiency in the bioanalytical work. Additionally, the availability of new emerging technological know-hows and latest nuances in the field should provide the necessary impetus to innovate and articulate strategies for smart assay development/validation work for analytes. PMID:19402178

  12. Clinical Scores for Dyspnoea Severity in Children: A Prospective Validation Study

    PubMed Central

    Eggink, Hendriekje; Brand, Paul; Reimink, Roelien; Bekhof, Jolita

    2016-01-01

    Background In acute dyspnoeic children, assessment of dyspnoea severity and treatment response is frequently based on clinical dyspnoea scores. Our study aim was to validate five commonly used paediatric dyspnoea scores. Methods Fifty children aged 0–8 years with acute dyspnoea were clinically assessed before and after bronchodilator treatment, a subset of 27 children were videotaped and assessed twice by nine observers. The observers scored clinical signs necessary to calculate the Asthma Score (AS), Asthma Severity Score (ASS), Clinical Asthma Evaluation Score 2 (CAES-2), Pediatric Respiratory Assessment Measure (PRAM) and respiratory rate, accessory muscle use, decreased breath sounds (RAD). Results A total of 1120 observations were used to assess fourteen measurement properties within domains of validity, reliability and utility. All five dyspnoea scores showed overall poor results, scoring insufficiently on more than half of the quality criteria for measurement properties. The AS and PRAM were the most valid with good values on six and moderate values on three properties. Poor results were mainly due to insufficient measurement properties in the validity and reliability domains whereas utility properties were moderate to good in all scores. Conclusion This study shows that commonly used dyspnoea scores show insufficient validity and reliability to allow for clinical use without caution. PMID:27382963

  13. 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.

  14. Solid state electrical conductivity and thermal degradation studies on some phenothiazine derivatives

    NASA Astrophysics Data System (ADS)

    Achar, B. N.; Ashok, M. A.

    2007-02-01

    Electrical conductivity and thermal degradation studies of promethazine hydrochloride (PH); 2-chlorophenothiazine (CP); diethazine hydrochloride (DH) and trifluoperazine dihydrochloride (TFP) are reported. The activation energies are evaluated based on their electrical conductivity study conducted over the temperature range 30 150 °C. These energies for PH, CP, DH and TFP are found to be 0.86, 1.02, 0.68 and 1.08 eV, respectively. The materials are analyzed for the kinetic parameters like the activation energies for decomposition and the Arrhenious pre-exponential factors in their pyrolysis region using Broido's, Coats Redfern and Horowitz Metzger methods. Using these factors and the standard equations thermodynamic parameters such as enthalpy, entropy and free energies are calculated. Thermogravimetric study on these phenothiazine derivatives in air indicated that their stabilities are in the order CP>TFP>PH >DH.

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

    PubMed

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

    2011-08-01

    Reverse transcription quantitative real-time PCR (RT-qPCR) is a sensitive technique for quantifying gene expression, but its success depends on the stability of the reference gene(s) used for data normalization. Only a few studies on validation of reference genes have been conducted in fruit trees and none in banana yet. In the present work, 20 candidate reference genes were selected, and their expression stability in 144 banana samples were evaluated and analyzed using two algorithms, geNorm and NormFinder. The samples consisted of eight sample sets collected under different experimental conditions, including various tissues, developmental stages, postharvest ripening, stresses (chilling, high temperature, and pathogen), and hormone treatments. Our results showed that different suitable reference gene(s) or combination of reference genes for normalization should be selected depending on the experimental conditions. The RPS2 and UBQ2 genes were validated as the most suitable reference genes across all tested samples. More importantly, our data further showed that the widely used reference genes, ACT and GAPDH, were not the most suitable reference genes in many banana sample sets. In addition, the expression of MaEBF1, a gene of interest that plays an important role in regulating fruit ripening, under different experimental conditions was used to further confirm the validated reference genes. Taken together, our results provide guidelines for reference gene(s) selection under different experimental conditions and a foundation for more accurate and widespread use of RT-qPCR in banana. PMID:21505864

  16. The Application of Spatial Signature Analysis to Electrical Test Data: Validation Study

    SciTech Connect

    Gleason, S.S.; Karnowski, T.P.; Lakhani, F.; Tobin, K.W.

    1999-03-15

    This paper presents the results of the Spatial Signature Analysis (SSA) Electrical-test (e-test) validation study that was conducted between February and June, 1998. SSA is an automated procedure developed by researchers at the Oak Ridge National Laboratory to address the issue of intelligent data reduction while providing feedback on current manufacturing processes. SSA was initially developed to automate the analysis of optical defect data. Optical defects can form groups, or clusters, which may have a distinct shape. These patterns can reveal information about the manufacturing process. Optical defect SSA uses image processing algorithms and a classifier system to interpret and identify these patterns, or signatures. SSA has been extended to analyze and interpret electrical test data. The algorithms used for optical defect SSA have been adapted and applied to e-test binmaps. An image of the binmap is created, and features such as geometric and invariant moments are extracted and presented to a pair-wise, fuzzy, k-NN classifier. The classifier itself was prepared by manually training, which consists of storing example signatures of interest in a library, then executing an automated process which treats the examples as prototype signatures. The training process includes a procedure for automatically determining which features are most relevant to each class. The evaluation was performed by installing the SSA software as a batch process at three SEMATECH member company sites. Feedback from member company representatives was incorporated and classifiers were built to automatically assign labels to the binmap signatures. The three sites produced memory devices (DRAM) and microprocessors in a mature process fabrication environment. For all of these products, 5,620 signatures that encompassed approximately 552 wafers were human-classified and analyzed. The performance of the SSA E-test system indicates that the approach was successful in reliably classifying binmap

  17. Bridging the gap between comprehensive extraction protocols in plant metabolomics studies and method validation.

    PubMed

    Bijttebier, Sebastiaan; Van der Auwera, Anastasia; Foubert, Kenn; Voorspoels, Stefan; Pieters, Luc; Apers, Sandra

    2016-09-01

    It is vital to pay much attention to the design of extraction methods developed for plant metabolomics, as any non-extracted or converted metabolites will greatly affect the overall quality of the metabolomics study. Method validation is however often omitted in plant metabolome studies, as the well-established methodologies for classical targeted analyses such as recovery optimization cannot be strictly applied. The aim of the present study is to thoroughly evaluate state-of-the-art comprehensive extraction protocols for plant metabolomics with liquid chromatography-photodiode array-accurate mass mass spectrometry (LC-PDA-amMS) by bridging the gap with method validation. Validation of an extraction protocol in untargeted plant metabolomics should ideally be accomplished by validating the protocol for all possible outcomes, i.e. for all secondary metabolites potentially present in the plant. In an effort to approach this ideal validation scenario, two plant matrices were selected based on their wide versatility of phytochemicals: meadowsweet (Filipendula ulmaria) for its polyphenols content, and spicy paprika powder (from the genus Capsicum) for its apolar phytochemicals content (carotenoids, phytosterols, capsaicinoids). These matrices were extracted with comprehensive extraction protocols adapted from literature and analysed with a generic LC-PDA-amMS characterization platform that was previously validated for broad range phytochemical analysis. The performance of the comprehensive sample preparation protocols was assessed based on extraction efficiency, repeatability and intermediate precision and on ionization suppression/enhancement evaluation. The manuscript elaborates on the finding that none of the extraction methods allowed to exhaustively extract the metabolites. Furthermore, it is shown that depending on the extraction conditions enzymatic degradation mechanisms can occur. Investigation of the fractions obtained with the different extraction methods

  18. In Situ Study of Strain-Dependent Ion Conductivity of Stretchable Polyethylene Oxide Electrolyte.

    PubMed

    Kelly, Taylor; Ghadi, Bahar Moradi; Berg, Sean; Ardebili, Haleh

    2016-01-01

    There is a strong need in developing stretchable batteries that can accommodate stretchable or irregularly shaped applications including medical implants, wearable devices and stretchable electronics. Stretchable solid polymer electrolytes are ideal candidates for creating fully stretchable lithium ion batteries mainly due to their mechanical and electrochemical stability, thin-film manufacturability and enhanced safety. However, the characteristics of ion conductivity of polymer electrolytes during tensile deformation are not well understood. Here, we investigate the effects of tensile strain on the ion conductivity of thin-film polyethylene oxide (PEO) through an in situ study. The results of this investigation demonstrate that both in-plane and through-plane ion conductivities of PEO undergo steady and linear growths with respect to the tensile strain. The coefficients of strain-dependent ion conductivity enhancement (CSDICE) for in-plane and through-plane conduction were found to be 28.5 and 27.2, respectively. Tensile stress-strain curves and polarization light microscopy (PLM) of the polymer electrolyte film reveal critical insights on the microstructural transformation of stretched PEO and the potential consequences on ionic conductivity. PMID:26831948

  19. A Study of the Preparation and Properties of Antioxidative Copper Inks with High Electrical Conductivity.

    PubMed

    Tsai, Chia-Yang; Chang, Wei-Chen; Chen, Guan-Lin; Chung, Cheng-Huan; Liang, Jun-Xiang; Ma, Wei-Yang; Yang, Tsun-Neng

    2015-12-01

    Conductive ink using copper nanoparticles has attracted much attention in the printed electronics industry because of its low cost and high electrical conductivity. However, the problem of easy oxidation under heat and humidity conditions for copper material limits the wide applications. In this study, antioxidative copper inks were prepared by dispersing the nanoparticles in the solution, and then conductive copper films can be obtained after calcining the copper ink at 250 °C in nitrogen atmosphere for 30 min. A low sheet resistance of 47.6 mΩ/□ for the copper film was measured by using the four-point probe method. Importantly, we experimentally demonstrate that the electrical conductivity of copper films can be improved by increasing the calcination temperature. In addition, these highly conductive copper films can be placed in an atmospheric environment for more than 6 months without the oxidation phenomenon, which was verified by energy-dispersive X-ray spectroscopy (EDS). These observations strongly show that our conductive copper ink features high antioxidant properties and long-term stability and has a great potential for many printed electronics applications, such as flexible display systems, sensors, photovoltaic cells, and radio frequency identification. PMID:26370132

  20. In Situ Study of Strain-Dependent Ion Conductivity of Stretchable Polyethylene Oxide Electrolyte

    PubMed Central

    Kelly, Taylor; Ghadi, Bahar Moradi; Berg, Sean; Ardebili, Haleh

    2016-01-01

    There is a strong need in developing stretchable batteries that can accommodate stretchable or irregularly shaped applications including medical implants, wearable devices and stretchable electronics. Stretchable solid polymer electrolytes are ideal candidates for creating fully stretchable lithium ion batteries mainly due to their mechanical and electrochemical stability, thin-film manufacturability and enhanced safety. However, the characteristics of ion conductivity of polymer electrolytes during tensile deformation are not well understood. Here, we investigate the effects of tensile strain on the ion conductivity of thin-film polyethylene oxide (PEO) through an in situ study. The results of this investigation demonstrate that both in-plane and through-plane ion conductivities of PEO undergo steady and linear growths with respect to the tensile strain. The coefficients of strain-dependent ion conductivity enhancement (CSDICE) for in-plane and through-plane conduction were found to be 28.5 and 27.2, respectively. Tensile stress-strain curves and polarization light microscopy (PLM) of the polymer electrolyte film reveal critical insights on the microstructural transformation of stretched PEO and the potential consequences on ionic conductivity. PMID:26831948

  1. A study of electrical conductance of meridian in the obese during weight reduction.

    PubMed

    Weng, Ching-Sung; Hung, Yu-Li; Shyu, Liang-Yu; Chang, Yung-Hsien

    2004-01-01

    This study was designed to investigate the electrical conductance of meridian in the obese during weight reduction. Ten obese including overweight (Body Mass Index, BMI > 26) and 30 healthy (non-overweight) people were recruited from Chung Yuan Christian University. The obese subjects were instructed to follow a weight reduction program that included diet control, exercise and oral intake of Prozac. A device, the design of which is based on the Ryodoraku theorem, was used to measure the electrical conductance of 12 meridians on both sides of the subjects. The results showed that: (1) the average coefficient of variation of the electrical conductances in 24 meridians of the obese group was statistically different from that of the healthy group (p < 0.05); (2) the average coefficient of variation of electrical conductance in the obese after weight reduction was significantly decreased than before the weight reduction program (p < 0.05); (3) the BMI and the electrical conductance of meridian was correlated in the obese (r = -0.77, p < 0.001) as well as in the healthy group (r = -0.92, p < 0.001). These findings suggest that electrical conductance of meridians can be a parameter to monitor weight, especially for obese people. PMID:15344425

  2. In Situ Study of Strain-Dependent Ion Conductivity of Stretchable Polyethylene Oxide Electrolyte

    NASA Astrophysics Data System (ADS)

    Kelly, Taylor; Ghadi, Bahar Moradi; Berg, Sean; Ardebili, Haleh

    2016-02-01

    There is a strong need in developing stretchable batteries that can accommodate stretchable or irregularly shaped applications including medical implants, wearable devices and stretchable electronics. Stretchable solid polymer electrolytes are ideal candidates for creating fully stretchable lithium ion batteries mainly due to their mechanical and electrochemical stability, thin-film manufacturability and enhanced safety. However, the characteristics of ion conductivity of polymer electrolytes during tensile deformation are not well understood. Here, we investigate the effects of tensile strain on the ion conductivity of thin-film polyethylene oxide (PEO) through an in situ study. The results of this investigation demonstrate that both in-plane and through-plane ion conductivities of PEO undergo steady and linear growths with respect to the tensile strain. The coefficients of strain-dependent ion conductivity enhancement (CSDICE) for in-plane and through-plane conduction were found to be 28.5 and 27.2, respectively. Tensile stress-strain curves and polarization light microscopy (PLM) of the polymer electrolyte film reveal critical insights on the microstructural transformation of stretched PEO and the potential consequences on ionic conductivity.

  3. Comparison of aquifer characterization approaches through steady state groundwater model validation: A controlled laboratory sandbox study

    USGS Publications Warehouse

    Illman, W.A.; Zhu, J.; Craig, A.J.; Yin, D.

    2010-01-01

    Groundwater modeling has become a vital component to water supply and contaminant transport investigations. An important component of groundwater modeling under steady state conditions is selecting a representative hydraulic conductivity (K) estimate or set of estimates which defines the K field of the studied region. Currently, there are a number of characterization approaches to obtain K at various scales and in varying degrees of detail, but there is a paucity of information in terms of which characterization approach best predicts flow through aquifers or drawdowns caused by some drawdown inducing events. The main objective of this paper is to assess K estimates obtained by various approaches by predicting drawdowns from independent cross-hole pumping tests and total flow rates through a synthetic heterogeneous aquifer from flow-through tests. Specifically, we (1) characterize a synthetic heterogeneous aquifer built in the sandbox through various techniques (permeameter analyses of core samples, single-hole, cross-hole, and flow-through testing), (2) obtain mean K fields through traditional analysis of test data by treating the medium to be homogeneous, (3) obtain heterogeneous K fields through kriging and steady state hydraulic tomography, and (4) conduct forward simulations of 16 independent pumping tests and six flowthrough tests using these homogeneous and heterogeneous K fields and comparing them to actual data. Results show that the mean K and heterogeneous K fields estimated through kriging of small-scale K data (core and single-hole tests) yield biased predictions of drawdowns and flow rates in this synthetic heterogeneous aquifer. In contrast, the heterogeneous K distribution or ?K tomogram? estimated via steady state hydraulic tomography yields excellent predictions of drawdowns of pumping tests not used in the construction of the tomogram and very good estimates of total flow rates from the flowthrough tests. These results suggest that steady state

  4. A Platform for the Remote Conduct of Gene-Environment Interaction Studies

    PubMed Central

    Gallacher, John; Collins, Rory; Elliott, Paul; Palmer, Stephen; Burton, Paul; Mitchell, Clive; John, Gareth; Lyons, Ronan

    2013-01-01

    Background Gene-environment interaction studies offer the prospect of robust causal inference through both gene identification and instrumental variable approaches. As such they are a major and much needed development. However, conducting these studies using traditional methods, which require direct participant contact, is resource intensive. The ability to conduct gene-environment interaction studies remotely would reduce costs and increase capacity. Aim To develop a platform for the remote conduct of gene-environment interaction studies. Methods A random sample of 15,000 men and women aged 50+ years and living in Cardiff, South Wales, of whom 6,012 were estimated to have internet connectivity, were mailed inviting them to visit a web-site to join a study of successful ageing. Online consent was obtained for questionnaire completion, cognitive testing, re-contact, record linkage and genotyping. Cognitive testing was conducted using the Cardiff Cognitive Battery. Bio-sampling was randomised to blood spot, buccal cell or no request. Results A heterogeneous sample of 663 (4.5% of mailed sample and 11% of internet connected sample) men and women (47% female) aged 50–87 years (median = 61 yrs) from diverse backgrounds (representing the full range of deprivation scores) was recruited. Bio-samples were donated by 70% of those agreeing to do so. Self report questionnaires and cognitive tests showed comparable distributions to those collected using face-to-face methods. Record linkage was achieved for 99.9% of participants. Conclusion This study has demonstrated that remote methods are suitable for the conduct of gene-environment interaction studies. Up-scaling these methods provides the opportunity to increase capacity for large-scale gene-environment interaction studies. PMID:23349852

  5. A study on Effective Thermal Conductivity of Packed Bed of Adsorbent Including Water

    NASA Astrophysics Data System (ADS)

    Hirasawa, Yoshio; Ohta, Ryuma; Takegoshi, Eisyun

    In the present study, an effective thermal conductivity of the packed bed of an adsorbent including water was measured experimentally by using the transient hot wire method in temperature range from about -40°C to room temperature. Zeolite particle and activated carbon particle were employed as the adsorbent. The water included in the adsorbent was classified to three kinds; namely, the adsorbed water in the adsorption site with a nanometer order in particle, the osmosis water existing in gap with lager size than the adsorption site and the free water around particle. The measurement was performed with changing the mass ratio of adsorbed water and osmosis water and was also performed for the particle filled by the free water. As the results, the effective thermal conductivity of the packed bed increased with the increase of temperature except the case containing free water. In zeolite, the effective thermal conductivity of the packed bed of particles with adsorbed water became bigger than that of the desorbed particle about 10% though the adsorbed water was trapped in the adsorption site as a single molecular in zeolite particle. In activated carbon, the effective thermal conductivity was larger than that of desorbed particle about 20%. Next, in the packed bed of particle with the osmosis water, the effective thermal conductivity indicated about two times of that of particle with the adsorbed water. In the packed bed of particle filled by free water, the effective thermal conductivity increased suddenly under 0°C. It is considered that the thermal conductivity of ice affected seriously to the effective thermal conductivity because ice was the continuous phase in the bed.

  6. Measured versus predicted performance of the SERI test house: a validation study

    SciTech Connect

    Judkoff, R.; Wortman, D.; Burch, J.

    1983-05-01

    For the past several years the United States Department of Energy (DOE) Passive and Hybrid Solar Division has sponsored work to improve the reliability of computerized building energy analysis simulations. Under the auspices of what has come to be called the Class A Monitoring and Validation program, the Solar Energy Research Institute (SERI) has engaged in several areas of research that includes: (1) developing a validation methodology; (2) developing a performance monitoring methodology designed to meet the specific data needs for validating analysis/design tools; (3) constructing and monitoring a 1000-ft/sup 2/, multizone, skin-load-dominated test building; (4) constructing and monitoring a two-zone test cell; and (5) making sample validation studies using the DOE-2.1, BLAST-3.0, and SERIRES-1.0 computer programs. This paper reports the results obtained in comparing the measured thermal performance of the building to the performance calculated by the building energy analysis simulations. It also describes the validation methodology and the class A data acquisition capabilities at SERI.

  7. Adaptation of Internet Addiction Scale in Azerbaijani Language: A Validity-Reliability and Prevalence Study

    ERIC Educational Resources Information Center

    Kerimova, Melek; Gunuc, Selim

    2016-01-01

    The purpose of the present paper was to adapt Gunuc and Kayri's (2010) "Internet Addiction Scale," with show validity and reliability for many various sampling groups, into the Azerbaijani language. Another objective of the study is to determine the prevalence of Internet addiction among Azerbaijani adolescents and youth, which…

  8. Open and Distance Education Accreditation Standards Scale: Validity and Reliability Studies

    ERIC Educational Resources Information Center

    Can, Ertug

    2016-01-01

    The purpose of this study is to develop, and test the validity and reliability of a scale for the use of researchers to determine the accreditation standards of open and distance education based on the views of administrators, teachers, staff and students. This research was designed according to the general descriptive survey model since it aims…

  9. Parent Reports of Young Spanish-English Bilingual Children's Productive Vocabulary: A Development and Validation Study

    ERIC Educational Resources Information Center

    Mancilla-Martinez, Jeannette; Gámez, Perla B.; Vagh, Shaher Banu; Lesaux, Nonie K.

    2016-01-01

    Purpose: This 2-phase study aims to extend research on parent report measures of children's productive vocabulary by investigating the development (n = 38) of the Spanish Vocabulary Extension and validity (n = 194) of the 100-item Spanish and English MacArthur-Bates Communicative Development Inventories Toddler Short Forms and Upward Extension…

  10. Measuring Classroom Assessment Practice Using Instructional Artifacts: A Validation Study of the QAS Notebook

    ERIC Educational Resources Information Center

    Martinez, Jose Felipe; Borko, Hilda; Stecher, Brian; Luskin, Rebecca; Kloser, Matt

    2012-01-01

    We report the results of a pilot validation study of the Quality Assessment in Science Notebook, a portfolio-like instrument for measuring teacher assessment practices in middle school science classrooms. A statewide sample of 42 teachers collected 2 notebooks during the school year, corresponding to science topics taught in the fall and spring.…

  11. Validity Study of the Autism Spectrum Disorders-Diagnostic for Children (ASD-DC)

    ERIC Educational Resources Information Center

    Matson, Johnny L.; Gonzalez, Melissa; Wilkins, Jonathan

    2009-01-01

    The Autism Spectrum Disorders-Diagnostic for Children (ASD-DC) is a 40-item Likert format scale designed to serve in the diagnosis of children and adolescents from 2 to 16 years of age. The reliability and factor structure of the scale have been established in previous research. Studies 1 and 2 were designed to evaluate the validity of the measure…

  12. Validating the Interpretations of PISA and TIMSS Tasks: A Rating Study

    ERIC Educational Resources Information Center

    Rindermann, Heiner; Baumeister, Antonia E. E.

    2015-01-01

    Scholastic tests regard cognitive abilities to be domain-specific competences. However, high correlations between competences indicate either high task similarity or a dependence on common factors. The present rating study examined the validity of 12 Programme for International Student Assessment (PISA) and Third or Trends in International…

  13. Introduction: The Comparative Study of Science and the Sociology of Scientific Validity.

    ERIC Educational Resources Information Center

    Holzner, Burkart; And Others

    1985-01-01

    Explores the social and cultural processes involved in the development of a social system of science in non-Western contexts. Proposes a sociology of science validity program for studying science in varying cultural and civilizational settings. Summarizes science development in China, India, Iran, and Japan. (ML)

  14. The Arabic Version of the Mayo-Portland Adaptability Inventory 4: A Validation Study

    ERIC Educational Resources Information Center

    Hamed, Razan; Tariah, Hashem Abu; Malkawi, Somaya; Holm, Margo B.

    2012-01-01

    The Mayo-Portland Adaptability Inventory 4 (MPAI-4) is a valid and reliable assessment tool to detect clinical impairments in patients with acquired brain injury. The tool is widely used by rehabilitation therapists worldwide, given its good psychometric properties and its availability in several languages. The purpose of this study was to…

  15. Incremental Validity of Thinking Styles in Predicting Academic Achievements: An Experimental Study in Hypermedia Learning Environments

    ERIC Educational Resources Information Center

    Fan, Weiqiao; Zhang, Li-Fang; Watkins, David

    2010-01-01

    The study examined the incremental validity of thinking styles in predicting academic achievement after controlling for personality and achievement motivation in the hypermedia-based learning environment. Seventy-two Chinese college students from Shanghai, the People's Republic of China, took part in this instructional experiment. The…

  16. A Construct Validity Study of Clinical Competence: A Multitrait Multimethod Matrix Approach

    ERIC Educational Resources Information Center

    Baig, Lubna; Violato, Claudio; Crutcher, Rodney

    2010-01-01

    Introduction: The purpose of the study was to adduce evidence for estimating the construct validity of clinical competence measured through assessment instruments used for high-stakes examinations. Methods: Thirty-nine international physicians (mean age = 41 + 6.5 y) participated in high-stakes examination and 3-month supervised clinical practice…

  17. A Comparative Study of Adolescent Risk Assessment Instruments: Predictive and Incremental Validity

    ERIC Educational Resources Information Center

    Welsh, Jennifer L.; Schmidt, Fred; McKinnon, Lauren; Chattha, H. K.; Meyers, Joanna R.

    2008-01-01

    Promising new adolescent risk assessment tools are being incorporated into clinical practice but currently possess limited evidence of predictive validity regarding their individual and/or combined use in risk assessments. The current study compares three structured adolescent risk instruments, Youth Level of Service/Case Management Inventory…

  18. The Dimensions of Learning Organization Questionnaire (DLOQ): A Validation Study in a Korean Context

    ERIC Educational Resources Information Center

    Song, Ji Hoon; Joo, Baek-Kyoo; Chermack, Thomas J.

    2009-01-01

    The purpose of this study is to assess the validity and reliability of the measurement scores of the learning organization culture, the Dimensions of Learning Organization Questionnaire (DLOQ), in a Korean context. A total of 1,529 cases from 11 firms in two major Korean conglomerates were analyzed. Rigorous translation procedures, including both…

  19. A Construct Validation Study of Phonological Awareness for Children Entering Prekindergarten

    ERIC Educational Resources Information Center

    Webb, Mi-Young Lee; Schwanenflugel, Paula J.; Kim, Seock-Ho

    2004-01-01

    The purpose of this study was to determine the psychometric characteristics of a phonological awareness assessment for prekindergarten children using Messick's (1989) framework for unitary construct validity. Upon entry into prekindergarten, children were given rhyme discrimination, syllable segmentation, initial phoneme isolation, and phoneme…

  20. Validating the Student Developmental Task and Lifestyle Assessment: A Longitudinal Study.

    ERIC Educational Resources Information Center

    Wachs, Peter M.; Cooper, Diane L.

    2002-01-01

    Study assessed the effectiveness of the Student Developmental Task and Lifestyle Assessment (SDTLA) in measuring psychosocial changes from the freshman year through the senior year using longitudinal research design. Results provide evidence of validity for the SDTLA and demonstrate that as a measurement tool, the SDTLA is sensitive to changes…