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Sample records for test sample study

  1. Sample Proficiency Test exercise

    Energy Technology Data Exchange (ETDEWEB)

    Alcaraz, A; Gregg, H; Koester, C

    2006-02-05

    The current format of the OPCW proficiency tests has multiple sets of 2 samples sent to an analysis laboratory. In each sample set, one is identified as a sample, the other as a blank. This method of conducting proficiency tests differs from how an OPCW designated laboratory would receive authentic samples (a set of three containers, each not identified, consisting of the authentic sample, a control sample, and a blank sample). This exercise was designed to test the reporting if the proficiency tests were to be conducted. As such, this is not an official OPCW proficiency test, and the attached report is one method by which LLNL might report their analyses under a more realistic testing scheme. Therefore, the title on the report ''Report of the Umpteenth Official OPCW Proficiency Test'' is meaningless, and provides a bit of whimsy for the analyses and readers of the report.

  2. Analysis of small sample size studies using nonparametric bootstrap test with pooled resampling method.

    Science.gov (United States)

    Dwivedi, Alok Kumar; Mallawaarachchi, Indika; Alvarado, Luis A

    2017-06-30

    Experimental studies in biomedical research frequently pose analytical problems related to small sample size. In such studies, there are conflicting findings regarding the choice of parametric and nonparametric analysis, especially with non-normal data. In such instances, some methodologists questioned the validity of parametric tests and suggested nonparametric tests. In contrast, other methodologists found nonparametric tests to be too conservative and less powerful and thus preferred using parametric tests. Some researchers have recommended using a bootstrap test; however, this method also has small sample size limitation. We used a pooled method in nonparametric bootstrap test that may overcome the problem related with small samples in hypothesis testing. The present study compared nonparametric bootstrap test with pooled resampling method corresponding to parametric, nonparametric, and permutation tests through extensive simulations under various conditions and using real data examples. The nonparametric pooled bootstrap t-test provided equal or greater power for comparing two means as compared with unpaired t-test, Welch t-test, Wilcoxon rank sum test, and permutation test while maintaining type I error probability for any conditions except for Cauchy and extreme variable lognormal distributions. In such cases, we suggest using an exact Wilcoxon rank sum test. Nonparametric bootstrap paired t-test also provided better performance than other alternatives. Nonparametric bootstrap test provided benefit over exact Kruskal-Wallis test. We suggest using nonparametric bootstrap test with pooled resampling method for comparing paired or unpaired means and for validating the one way analysis of variance test results for non-normal data in small sample size studies. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  3. Parametric and nonparametric two-sample tests for feature screening in class comparison: a simulation study

    Directory of Open Access Journals (Sweden)

    Elena Landoni

    2016-06-01

    Full Text Available Background. The identification of a location-, scale- and shape-sensitive test to detect differentially expressed features between two comparison groups represents a key point in high dimensional studies. The most commonly used tests refer to differences in location, but general distributional discrepancies might be important to reveal differential biological processes.                                                         Methods. A simulation study was conducted to compare the performance of a set of two-sample tests, i.e. Student's t, Welch's t, Wilcoxon-Mann-Whitney, Podgor-Gastwirth PG2, Cucconi, Kolmogorov-Smirnov (KS, Cramer-von Mises (CvM, Anderson-Darling (AD and Zhang tests (ZK, ZC and ZA which were investigated under different distributional patterns. We applied the same tests to a real data example.                   Results. AD, CvM, ZA and ZC tests proved to be the most sensitive tests in mixture distribution patterns, while still maintaining a high power in normal distribution patterns. At best, the AD test showed a loss in power of ~ 2% in the comparison of two normal distributions, but a gain of ~ 32% with mixture distributions respect to the parametric tests. Accordingly, the AD test detected the greatest number of differentially expressed features in the real data application.   Conclusion. The tests for the general two-sample problem introduce a more general concept of 'differential expression', thus overcoming the limitations of the other tests restricted to specific moments of the feature distributions. In particular, the AD test should be considered as a powerful alternative to the parametric tests for feature screening in order to keep as many discriminative features as possible for the class prediction analysis.

  4. Sample Size Determination in a Chi-Squared Test Given Information from an Earlier Study.

    Science.gov (United States)

    Gillett, Raphael

    1996-01-01

    A rigorous method is outlined for using information from a previous study and explicitly taking into account the variability of an effect size estimate when determining sample size for a chi-squared test. This approach assures that the average power of all experiments in a discipline attains the desired level. (SLD)

  5. Validation study of a multi-method integrity test in a Peruvian sample

    OpenAIRE

    Blumen, Sheyla; Bayona, Hugo; Givoli, Simon; Pecker, Gabriela; Fine, Saul

    2016-01-01

    The present study summarizes the validity of a multi-method integrity test developed to measure integrity and counterproductive work behaviors (CWB) in personnel selection of a Peruvian sample. This instrument has been thoroughly studied in other cultural contexts, establishing its validity in predicting counter-productive behaviors. In order to study external validity, two criteria were used: (a) The Counterproductive Work Behavior Checklist (CWB-C) and (b) a supervisor evaluation questionna...

  6. Mold Testing or Sampling

    Science.gov (United States)

    In most cases, if visible mold growth is present, sampling is unnecessary. Since no EPA or other federal limits have been set for mold or mold spores, sampling cannot be used to check a building's compliance with federal mold standards.

  7. External validity study of a personality disorders screening test in a community sample

    OpenAIRE

    Carvalho, Lucas de Francisco

    2017-01-01

    Abstract Background A screening test for personality disorders was recently developed in Brazil, the Dimensional Clinical Personality Inventory – screening version (IDCP-SV). However, no relationship between this screening measure and other scales or external criteria was tested. Objective To seek for validity evidence based on related criteria (e.g., other psychological tests) and external criteria (e.g., sample demographics). Methods Sample comprised 804 participants from São Paulo (B...

  8. Collecting Samples for Testing

    Science.gov (United States)

    ... Acidosis and Alkalosis Adrenal Insufficiency and Addison Disease Alcoholism Allergies Alzheimer Disease Anemia Angina Ankylosing Spondylitis Anthrax ... through Their Medical Tests Tips to Help the Elderly through Their Medical Tests Related Video View More × ...

  9. A study of correlations between crude oil spot and futures markets: A rolling sample test

    Science.gov (United States)

    Liu, Li; Wan, Jieqiu

    2011-10-01

    In this article, we investigate the asymmetries of exceedance correlations and cross-correlations between West Texas Intermediate (WTI) spot and futures markets. First, employing the test statistic proposed by Hong et al. [Asymmetries in stock returns: statistical tests and economic evaluation, Review of Financial Studies 20 (2007) 1547-1581], we find that the exceedance correlations were overall symmetric. However, the results from rolling windows show that some occasional events could induce the significant asymmetries of the exceedance correlations. Second, employing the test statistic proposed by Podobnik et al. [Quantifying cross-correlations using local and global detrending approaches, European Physics Journal B 71 (2009) 243-250], we find that the cross-correlations were significant even for large lagged orders. Using the detrended cross-correlation analysis proposed by Podobnik and Stanley [Detrended cross-correlation analysis: a new method for analyzing two nonstationary time series, Physics Review Letters 100 (2008) 084102], we find that the cross-correlations were weakly persistent and were stronger between spot and futures contract with larger maturity. Our results from rolling sample test also show the apparent effects of the exogenous events. Additionally, we have some relevant discussions on the obtained evidence.

  10. External validity study of a personality disorders screening test in a community sample

    Directory of Open Access Journals (Sweden)

    Lucas de Francisco Carvalho

    Full Text Available Abstract Background A screening test for personality disorders was recently developed in Brazil, the Dimensional Clinical Personality Inventory – screening version (IDCP-SV. However, no relationship between this screening measure and other scales or external criteria was tested. Objective To seek for validity evidence based on related criteria (e.g., other psychological tests and external criteria (e.g., sample demographics. Methods Sample comprised 804 participants from São Paulo (Brazil, most female and college students, with mean age equal to 29.65 (SD = 10.73. They answered the IDCP-SV and another screening for personality disorders (IPDS, a depression measure (EBADEP-screening, a scale assessing reasoning for living (EMVIVER, and a self-report for personality disorders categories assessment (SCID-II-PQ. Results IDCP-SV identified 46.4% of community sample as positive for personality disorders. The positive group showed the great mean for almost all comparisions, including psychological tests and the demographics characteristics, including large expressive effect sizes. Discussion Data suggest that the IDCP-SV discriminates a similar percentage of people from the community to what was reported previously using other screening measures; besides, the mean comparisons between groups showed good discriminative capacity by IDCP-SV items.

  11. Mixing studies in lupus anticoagulant testing are required at least in some type of samples.

    Science.gov (United States)

    Devreese, K M J; de Laat, B

    2015-08-01

    According to the ISTH guidelines for lupus anticoagulant (LAC) testing, the second step in the three-step procedure (screening, mixing, and confirmation) is the mixing test, which improves the discrimination between the presence of an inhibitor and coagulation factor deficiencies such as those occurring in patients receiving vitamin K antagonists (VKAs). From a retrospective analysis of dilute Russell viper venom (dRVVT) results, we evaluated the impact of the mixing test result on the interpretation of LAC positivity. We interpreted the dRVVT clotting times with and without taking into account the results of the mixing test in a patient population with prolonged screening test (n = 267) with special attention to the patients receiving VKAs. The number of samples classified as 'LAC positive' differed substantially depending on the method of interpretation; 170 and 235 of 267 samples were classified as LAC positive with the three- and two-step procedure, respectively. Discrepancy between the two-step (without mixing step) and the three-step procedure was due to not including a mixing test and was more pronounced in the VKA patient population. Screen/confirm ratios carried out on a 1:1 mix of patient and normal pooled plasma (NPP) gave a lower incidence of 59 of 267. We advise continuing to perform mixing test to avoid false-positives. In patients with discrepant results between the two- and three-step dRVVT interpretation, mainly observed in VKA-treated patients, we advise retesting of the patients preferable beyond the period of anticoagulant therapy and additional testing for anti-beta2GPI and/or anti-cardiolipin antibodies. © 2015 International Society on Thrombosis and Haemostasis.

  12. Tests on standard concrete samples

    CERN Multimedia

    CERN PhotoLab

    1973-01-01

    Compression and tensile tests on standard concrete samples. The use of centrifugal force in tensile testing has been developed by the SB Division and the instruments were built in the Central workshops.

  13. The Predictive Validity of Four Intelligence Tests for School Grades: A Small Sample Longitudinal Study.

    Science.gov (United States)

    Gygi, Jasmin T; Hagmann-von Arx, Priska; Schweizer, Florine; Grob, Alexander

    2017-01-01

    Intelligence is considered the strongest single predictor of scholastic achievement. However, little is known regarding the predictive validity of well-established intelligence tests for school grades. We analyzed the predictive validity of four widely used intelligence tests in German-speaking countries: The Intelligence and Development Scales (IDS), the Reynolds Intellectual Assessment Scales (RIAS), the Snijders-Oomen Nonverbal Intelligence Test (SON-R 6-40), and the Wechsler Intelligence Scale for Children (WISC-IV), which were individually administered to 103 children (Mage = 9.17 years) enrolled in regular school. School grades were collected longitudinally after 3 years (averaged school grades, mathematics, and language) and were available for 54 children (Mage = 11.77 years). All four tests significantly predicted averaged school grades. Furthermore, the IDS and the RIAS predicted both mathematics and language, while the SON-R 6-40 predicted mathematics. The WISC-IV showed no significant association with longitudinal scholastic achievement when mathematics and language were analyzed separately. The results revealed the predictive validity of currently used intelligence tests for longitudinal scholastic achievement in German-speaking countries and support their use in psychological practice, in particular for predicting averaged school grades. However, this conclusion has to be considered as preliminary due to the small sample of children observed.

  14. The Predictive Validity of Four Intelligence Tests for School Grades: A Small Sample Longitudinal Study

    Science.gov (United States)

    Gygi, Jasmin T.; Hagmann-von Arx, Priska; Schweizer, Florine; Grob, Alexander

    2017-01-01

    Intelligence is considered the strongest single predictor of scholastic achievement. However, little is known regarding the predictive validity of well-established intelligence tests for school grades. We analyzed the predictive validity of four widely used intelligence tests in German-speaking countries: The Intelligence and Development Scales (IDS), the Reynolds Intellectual Assessment Scales (RIAS), the Snijders-Oomen Nonverbal Intelligence Test (SON-R 6-40), and the Wechsler Intelligence Scale for Children (WISC-IV), which were individually administered to 103 children (Mage = 9.17 years) enrolled in regular school. School grades were collected longitudinally after 3 years (averaged school grades, mathematics, and language) and were available for 54 children (Mage = 11.77 years). All four tests significantly predicted averaged school grades. Furthermore, the IDS and the RIAS predicted both mathematics and language, while the SON-R 6-40 predicted mathematics. The WISC-IV showed no significant association with longitudinal scholastic achievement when mathematics and language were analyzed separately. The results revealed the predictive validity of currently used intelligence tests for longitudinal scholastic achievement in German-speaking countries and support their use in psychological practice, in particular for predicting averaged school grades. However, this conclusion has to be considered as preliminary due to the small sample of children observed. PMID:28348543

  15. A score test for determining sample size in matched case-control studies with categorical exposure.

    Science.gov (United States)

    Sinha, Samiran; Mukherjee, Bhramar

    2006-02-01

    The paper considers the problem of determining the number of matched sets in 1 : M matched case-control studies with a categorical exposure having k + 1 categories, k > or = 1. The basic interest lies in constructing a test statistic to test whether the exposure is associated with the disease. Estimates of the k odds ratios for 1 : M matched case-control studies with dichotomous exposure and for 1 : 1 matched case-control studies with exposure at several levels are presented in Breslow and Day (1980), but results holding in full generality were not available so far. We propose a score test for testing the hypothesis of no association between disease and the polychotomous exposure. We exploit the power function of this test statistic to calculate the required number of matched sets to detect specific departures from the null hypothesis of no association. We also consider the situation when there is a natural ordering among the levels of the exposure variable. For ordinal exposure variables, we propose a test for detecting trend in disease risk with increasing levels of the exposure variable. Our methods are illustrated with two datasets, one is a real dataset on colorectal cancer in rats and the other a simulated dataset for studying disease-gene association.

  16. Sample size determination for a t test given a t value from a previous study: A FORTRAN 77 program.

    Science.gov (United States)

    Gillett, R

    2001-11-01

    When uncertain about the magnitude of an effect, researchers commonly substitute in the standard sample-size-determination formula an estimate of effect size derived from a previous experiment. A problem with this approach is that the traditional sample-size-determination formula was not designed to deal with the uncertainty inherent in an effect-size estimate. Consequently, estimate-substitution in the traditional sample-size-determination formula can lead to a substantial loss of power. A method of sample-size determination designed to handle uncertainty in effect-size estimates is described. The procedure uses the t value and sample size from a previous study, which might be a pilot study or a related study in the same area, to establish a distribution of probable effect sizes. The sample size to be employed in the new study is that which supplies an expected power of the desired amount over the distribution of probable effect sizes. A FORTRAN 77 program is presented that permits swift calculation of sample size for a variety of t tests, including independent t tests, related t tests, t tests of correlation coefficients, and t tests of multiple regression b coefficients.

  17. Metacognitive training in patients recovering from a first psychosis: an experience sampling study testing treatment effects.

    Science.gov (United States)

    Pos, Karin; Meijer, Carin J; Verkerk, Oukje; Ackema, Onno; Krabbendam, Lydia; de Haan, Lieuwe

    2018-02-01

    Cognitive biases, negative affect and negative self-esteem are associated with paranoia in people with psychotic disorders. Metacognitive group training (MCT) aims to target these biases although research has shown mixed results. Our objective was to establish the effect of MCT on paranoid ideation in patients with recent onset psychosis in a powerful experience sampling design. 50 patients between the age of 18 and 35 were included in a single-blind, parallel group RCT comparing MCT with occupational therapy (OT) as an active control condition. We assessed via questionnaires and experience sampling treatment effects on paranoid ideation, delusional conviction, the cognitive bias jumping to conclusion (JTC), and cognitive insight, as well as treatment effects on associations between negative affect, negative self-esteem and paranoid ideation. Patients in the MCT group did not show a decrease in paranoid ideation, delusional conviction, JTC-bias or an increase in cognitive insight compared with OT. However, negative affect showed a weaker association with paranoid ideation post-treatment in the MCT condition. In the OT condition, this association was stronger post-treatment. We tentatively suggest that patients with an early psychosis seemed to benefit from MCT in emotional learning compared with the OT condition. Despite the fact that the group training is well-received by patients, subsequent individual MCT (MCT+) may be indicated for stronger favorable effects on paranoid ideation.

  18. Biological Sampling Variability Study

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-11-08

    There are many sources of variability that exist in the sample collection and analysis process. This paper addresses many, but not all, sources of variability. The main focus of this paper was to better understand and estimate variability due to differences between samplers. Variability between days was also studied, as well as random variability within each sampler. Experiments were performed using multiple surface materials (ceramic and stainless steel), multiple contaminant concentrations (10 spores and 100 spores), and with and without the presence of interfering material. All testing was done with sponge sticks using 10-inch by 10-inch coupons. Bacillus atrophaeus was used as the BA surrogate. Spores were deposited using wet deposition. Grime was coated on the coupons which were planned to include the interfering material (Section 3.3). Samples were prepared and analyzed at PNNL using CDC protocol (Section 3.4) and then cultured and counted. Five samplers were trained so that samples were taken using the same protocol. Each sampler randomly sampled eight coupons each day, four coupons with 10 spores deposited and four coupons with 100 spores deposited. Each day consisted of one material being tested. The clean samples (no interfering materials) were run first, followed by the dirty samples (coated with interfering material). There was a significant difference in recovery efficiency between the coupons with 10 spores deposited (mean of 48.9%) and those with 100 spores deposited (mean of 59.8%). There was no general significant difference between the clean and dirty (containing interfering material) coupons or between the two surface materials; however, there was a significant interaction between concentration amount and presence of interfering material. The recovery efficiency was close to the same for coupons with 10 spores deposited, but for the coupons with 100 spores deposited, the recovery efficiency for the dirty samples was significantly larger (65

  19. A Shandon PapSpin liquid-based gynecological test: A split-sample and direct-to-vial test with histology follow-up study

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    Rimiene J

    2010-01-01

    Full Text Available Background: Studies for liquid-based Papanicolaou (Pap tests reveal that liquid-based cytology (LBC is a safe and effective alternative to the conventional Pap smear. Although there is research on ThinPrep and SurePath systems, information is lacking to evaluate the efficiency and effectiveness of systems based on cytocentrifugation. This study is designed to determine the sensitivity and specificity of the Shandon PapSpin (ThermoShandon, Pittsburgh, Pennsylvania, USA liquid-based gynecological system. We used split-sample and direct-to-vial study design. Materials and Methods: 2,945 women referred to prophylactic check-up were enrolled in this study. Split sample design was used in 1,500 women and residual cervical cytology specimen from all these cases was placed in fluid for PapSpin preparation after performing conventional smear. The direct-to-vial study was carried out in another cohort of 1,445 women in whom the entire cervical material was investigated using only the PapSpin technique. Follow up histological diagnoses for 141 women were obtained from both study arms following 189 abnormal cytology cases. 80 LBC cases from the split sample group and 61 LBC cases in the direct-to-vial group were correlated with the histology results. The sensitivity and secificity of the conventional smear and PapSpin tests in both study arms were compared. Results: In the split sample group, conventional smears showed a higher proportion of ASC-US (atypical cells undetermined significance: 31 (2.1% vs 10 (0.7% in PapSpin (P = 0.001. A higher proportion of unsatisfactory samples was found in the conventional smear group: 25 (1.7% vs 6 (0.4% cases (P = 0.001. In the split sample group, the sensitivity of the conventional and PapSpin tests was 68.7% vs 78.1%, and the specificity 93.8% vs 91.8%, respectively. In the direct to vial group PapSpin sensitivity was 75.9% and specificity 96.5%. The differences in sensitivity and specificity were not significant. The

  20. Commutability of food microbiology proficiency testing samples.

    Science.gov (United States)

    Abdelmassih, M; Polet, M; Goffaux, M-J; Planchon, V; Dierick, K; Mahillon, J

    2014-03-01

    Food microbiology proficiency testing (PT) is a useful tool to assess the analytical performances among laboratories. PT items should be close to routine samples to accurately evaluate the acceptability of the methods. However, most PT providers distribute exclusively artificial samples such as reference materials or irradiated foods. This raises the issue of the suitability of these samples because the equivalence-or 'commutability'-between results obtained on artificial vs. authentic food samples has not been demonstrated. In the clinical field, the use of noncommutable PT samples has led to erroneous evaluation of the performances when different analytical methods were used. This study aimed to provide a first assessment of the commutability of samples distributed in food microbiology PT. REQUASUD and IPH organized 13 food microbiology PTs including 10-28 participants. Three types of PT items were used: genuine food samples, sterile food samples and reference materials. The commutability of the artificial samples (reference material or sterile samples) was assessed by plotting the distribution of the results on natural and artificial PT samples. This comparison highlighted matrix-correlated issues when nonfood matrices, such as reference materials, were used. Artificially inoculated food samples, on the other hand, raised only isolated commutability issues. In the organization of a PT-scheme, authentic or artificially inoculated food samples are necessary to accurately evaluate the analytical performances. Reference materials, used as PT items because of their convenience, may present commutability issues leading to inaccurate penalizing conclusions for methods that would have provided accurate results on food samples. For the first time, the commutability of food microbiology PT samples was investigated. The nature of the samples provided by the organizer turned out to be an important factor because matrix effects can impact on the analytical results. © 2013

  1. New prior sampling methods for nested sampling - Development and testing

    Science.gov (United States)

    Stokes, Barrie; Tuyl, Frank; Hudson, Irene

    2017-06-01

    Nested Sampling is a powerful algorithm for fitting models to data in the Bayesian setting, introduced by Skilling [1]. The nested sampling algorithm proceeds by carrying out a series of compressive steps, involving successively nested iso-likelihood boundaries, starting with the full prior distribution of the problem parameters. The "central problem" of nested sampling is to draw at each step a sample from the prior distribution whose likelihood is greater than the current likelihood threshold, i.e., a sample falling inside the current likelihood-restricted region. For both flat and informative priors this ultimately requires uniform sampling restricted to the likelihood-restricted region. We present two new methods of carrying out this sampling step, and illustrate their use with the lighthouse problem [2], a bivariate likelihood used by Gregory [3] and a trivariate Gaussian mixture likelihood. All the algorithm development and testing reported here has been done with Mathematica® [4].

  2. Prothrombin Time and Activated Partial Thromboplastin Time Testing: A Comparative Effectiveness Study in a Million-Patient Sample.

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    Manu N Capoor

    Full Text Available A substantial fraction of all American healthcare expenditures are potentially wasted, and practices that are not evidence-based could contribute to such waste. We sought to characterize whether Prothrombin Time (PT and activated Partial Thromboplastin Time (aPTT tests of preoperative patients are used in a way unsupported by evidence and potentially wasteful.We evaluated prospectively-collected patient data from 19 major teaching hospitals and 8 hospital-affiliated surgical centers in 7 states (Delaware, Florida, Maryland, Massachusetts, New Jersey, New York, Pennsylvania and the District of Columbia. A total of 1,053,472 consecutive patients represented every patient admitted for elective surgery from 2009 to 2012 at all 27 settings. A subset of 682,049 patients (64.7% had one or both tests done and history and physical (H&P records available for analysis. Unnecessary tests for bleeding risk were defined as: PT tests done on patients with no history of abnormal bleeding, warfarin therapy, vitamin K-dependent clotting factor deficiency, or liver disease; or aPTT tests done on patients with no history of heparin treatment, hemophilia, lupus anticoagulant antibodies, or von Willebrand disease. We assessed the proportion of patients who received PT or aPTT tests who lacked evidence-based reasons for testing.This study sought to bring the availability of big data together with applied comparative effectiveness research. Among preoperative patients, 26.2% received PT tests, and 94.3% of tests were unnecessary, given the absence of findings on H&P. Similarly, 23.3% of preoperative patients received aPTT tests, of which 99.9% were unnecessary. Among patients with no H&P findings suggestive of bleeding risk, 6.6% of PT tests and 7.1% of aPTT tests were either a false positive or a true positive (i.e. indicative of a previously-undiagnosed potential bleeding risk. Both PT and aPTT, designed as diagnostic tests, are apparently used as screening tests

  3. Airflow Test of Acoustic Board Samples

    DEFF Research Database (Denmark)

    Jensen, Rasmus Lund; Jensen, Lise Mellergaard

    In the laboratory of Indoor Environmental Engineering, Department of Civil Engineering, Aalborg University an airflow test on 2x10 samples of acoustic board were carried out the 2nd of June 2012. The tests were carried out for Rambøll and STO AG. The test includes connected values of volume flow...

  4. Longitudinal Study of Hepatitis A Infection by Saliva Sampling: The Kinetics of HAV Markers in Saliva Revealed the Application of Saliva Tests for Hepatitis A Study

    Science.gov (United States)

    Amado Leon, Luciane Almeida; de Almeida, Adilson José; de Paula, Vanessa Salete; Tourinho, Renata Santos; Villela, Daniel Antunes Maciel; Gaspar, Ana Maria Coimbra; Lewis-Ximenez, Lia Laura; Pinto, Marcelo Alves

    2015-01-01

    Despite the increasing numbers of studies investigating hepatitis A diagnostic through saliva, the frequency and the pattern of hepatitis A virus (HAV) markers in this fluid still remains unknown. To address this issue, we carried on a longitudinal study to examine the kinetics of HAV markers in saliva, in comparison with serum samples. The present study followed-up ten patients with acute hepatitis A infection during 180 days post diagnosis (dpd). Total anti-HAV was detected in paired serum and saliva samples until the end of the follow-up, showing a peak titer at 90th. However, total anti-HAV level was higher in serum than in saliva samples. This HAV marker showed a probability of 100% to be detected in both serum and saliva during 180 dpd. The IgM anti-HAV could be detected in saliva up to 150 dpd, showing the highest frequency at 30th, when it was detected in all individuals. During the first month of HAV infection, this acute HAV marker showed a detection probability of 100% in paired samples. The detection of IgM anti-HAV in saliva was not dependent on its level in serum, HAV-RNA detection and/or viral load, since no association was found between IgM anti-HAV positivity in saliva and any of these parameter (p>0.05). Most of the patients (80%) were found to contain HAV-RNA in saliva, mainly at early acute phase (30th day). However, it was possible to demonstrate the HAV RNA presence in paired samples for more than 90 days, even after seroconversion. No significant relationship was observed between salivary HAV-RNA positivity and serum viral load, demonstrating that serum viral load is not predictive of HAV-RNA detection in saliva. Similar viral load was seen in paired samples (on average 104 copies/mL). These data demonstrate that the best diagnostic coverage can be achieved by salivary anti-HAV antibodies and HAV-RNA tests during 30–90 dpd. The long detection and high probability of specific-HAV antibodies positivity in saliva samples make the assessment of

  5. Longitudinal Study of Hepatitis A Infection by Saliva Sampling: The Kinetics of HAV Markers in Saliva Revealed the Application of Saliva Tests for Hepatitis A Study.

    Science.gov (United States)

    Amado Leon, Luciane Almeida; de Almeida, Adilson José; de Paula, Vanessa Salete; Tourinho, Renata Santos; Villela, Daniel Antunes Maciel; Gaspar, Ana Maria Coimbra; Lewis-Ximenez, Lia Laura; Pinto, Marcelo Alves

    2015-01-01

    Despite the increasing numbers of studies investigating hepatitis A diagnostic through saliva, the frequency and the pattern of hepatitis A virus (HAV) markers in this fluid still remains unknown. To address this issue, we carried on a longitudinal study to examine the kinetics of HAV markers in saliva, in comparison with serum samples. The present study followed-up ten patients with acute hepatitis A infection during 180 days post diagnosis (dpd). Total anti-HAV was detected in paired serum and saliva samples until the end of the follow-up, showing a peak titer at 90th. However, total anti-HAV level was higher in serum than in saliva samples. This HAV marker showed a probability of 100% to be detected in both serum and saliva during 180 dpd. The IgM anti-HAV could be detected in saliva up to 150 dpd, showing the highest frequency at 30th, when it was detected in all individuals. During the first month of HAV infection, this acute HAV marker showed a detection probability of 100% in paired samples. The detection of IgM anti-HAV in saliva was not dependent on its level in serum, HAV-RNA detection and/or viral load, since no association was found between IgM anti-HAV positivity in saliva and any of these parameter (p>0.05). Most of the patients (80%) were found to contain HAV-RNA in saliva, mainly at early acute phase (30th day). However, it was possible to demonstrate the HAV RNA presence in paired samples for more than 90 days, even after seroconversion. No significant relationship was observed between salivary HAV-RNA positivity and serum viral load, demonstrating that serum viral load is not predictive of HAV-RNA detection in saliva. Similar viral load was seen in paired samples (on average 104 copies/mL). These data demonstrate that the best diagnostic coverage can be achieved by salivary anti-HAV antibodies and HAV-RNA tests during 30-90 dpd. The long detection and high probability of specific-HAV antibodies positivity in saliva samples make the assessment of

  6. Longitudinal Study of Hepatitis A Infection by Saliva Sampling: The Kinetics of HAV Markers in Saliva Revealed the Application of Saliva Tests for Hepatitis A Study.

    Directory of Open Access Journals (Sweden)

    Luciane Almeida Amado Leon

    Full Text Available Despite the increasing numbers of studies investigating hepatitis A diagnostic through saliva, the frequency and the pattern of hepatitis A virus (HAV markers in this fluid still remains unknown. To address this issue, we carried on a longitudinal study to examine the kinetics of HAV markers in saliva, in comparison with serum samples. The present study followed-up ten patients with acute hepatitis A infection during 180 days post diagnosis (dpd. Total anti-HAV was detected in paired serum and saliva samples until the end of the follow-up, showing a peak titer at 90th. However, total anti-HAV level was higher in serum than in saliva samples. This HAV marker showed a probability of 100% to be detected in both serum and saliva during 180 dpd. The IgM anti-HAV could be detected in saliva up to 150 dpd, showing the highest frequency at 30th, when it was detected in all individuals. During the first month of HAV infection, this acute HAV marker showed a detection probability of 100% in paired samples. The detection of IgM anti-HAV in saliva was not dependent on its level in serum, HAV-RNA detection and/or viral load, since no association was found between IgM anti-HAV positivity in saliva and any of these parameter (p>0.05. Most of the patients (80% were found to contain HAV-RNA in saliva, mainly at early acute phase (30th day. However, it was possible to demonstrate the HAV RNA presence in paired samples for more than 90 days, even after seroconversion. No significant relationship was observed between salivary HAV-RNA positivity and serum viral load, demonstrating that serum viral load is not predictive of HAV-RNA detection in saliva. Similar viral load was seen in paired samples (on average 104 copies/mL. These data demonstrate that the best diagnostic coverage can be achieved by salivary anti-HAV antibodies and HAV-RNA tests during 30-90 dpd. The long detection and high probability of specific-HAV antibodies positivity in saliva samples make the

  7. Study of the effects of low-fluence laser irradiation on wall paintings: Test measurements on fresco model samples

    Energy Technology Data Exchange (ETDEWEB)

    Raimondi, Valentina, E-mail: v.raimondi@ifac.cnr.it [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Cucci, Costanza [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Cuzman, Oana [Institute for the Conservation and Promotion of Cultural Heritage-National Research Council (CNR-ICVBC), Firenze (Italy); Fornacelli, Cristina [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Galeotti, Monica [Opificio delle Pietre Dure (OPD), Firenze (Italy); Gomoiu, Ioana [National University of Art, Bucharest (Romania); Lognoli, David [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Mohanu, Dan [National University of Art, Bucharest (Romania); Palombi, Lorenzo; Picollo, Marcello [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Tiano, Piero [Institute for the Conservation and Promotion of Cultural Heritage-National Research Council (CNR-ICVBC), Firenze (Italy)

    2013-11-01

    Laser-induced fluorescence is widely applied in several fields as a diagnostic tool to characterise organic and inorganic materials and could be also exploited for non-invasive remote investigation of wall paintings using the fluorescence lidar technique. The latter relies on the use of a low-fluence pulsed UV laser and a telescope to carry out remote spectroscopy on a given target. A first step to investigate the applicability of this technique is to assess the effects of low-fluence laser radiation on wall paintings. This paper presents a study devoted to investigate the effects of pulsed UV laser radiation on a set of fresco model samples prepared using different pigments. To irradiate the samples we used a tripled-frequency Q-switched Nd:YAG laser (emission wavelength: 355 nm; pulse width: 5 ns). We varied the laser fluence from 0.1 mJ/cm{sup 2} to 1 mJ/cm{sup 2} and the number of laser pulses from 1 to 500 shots. We characterised the investigated materials using several diagnostic and analytical techniques (colorimetry, optical microscopy, fibre optical reflectance spectroscopy and ATR-FT-IR microscopy) to compare the surface texture and their composition before and after laser irradiation. Results open good prospects for a non-invasive investigation of wall paintings using the fluorescence lidar technique.

  8. Outgassing tests on iras solar panel samples

    Science.gov (United States)

    Premat, G.; Zwaal, A.; Pennings, N. H.

    1980-01-01

    Several outgassing tests were carried out on representative solar panel samples in order to determine the extent of contamination that could be expected from this source. The materials for the construction of the solar panels were selected as a result of contamination obtained in micro volatile condensable materials tests.

  9. A pilot study of community-based self-sampling for HPV testing among non-attenders of cervical cancer screening programs in El Salvador.

    Science.gov (United States)

    Laskow, Bari; Figueroa, Ruben; Alfaro, Karla M; Scarinci, Isabel C; Conlisk, Elizabeth; Maza, Mauricio; Chang, Judy C; Cremer, Miriam

    2017-08-01

    To establish the feasibility and acceptability of home-based HPV self-sampling among women who did not attend screening appointments in rural El Salvador. In a cross-sectional study, data were collected from May 2015 to January 2016 among 60 women aged 30-59 years who were not pregnant, provided informed consent, had not been screened in 2 years, had no history of pre-cancer treatment, and did not attend a scheduled HPV screening. Participants completed questionnaires and received educational information before being given an opportunity to self-sample with the Hybrid Capture 2 High Risk HPV DNA Test. Self-sampling was accepted by 41 (68%) participants. Almost all women chose to self-sample because the process was easy (40/41, 98%), could be performed at home (40/41, 98%), and saved time (38/41, 93%), and because they felt less embarrassed (33/41, 80%). The most common reason for declining the test was not wanting to be screened (8/19, 42%). The prevalence of high-risk HPV types among women who accepted self-sampling was 17% (7/41). For most women, community-based self-sampling was an acceptable way to participate in a cervical cancer screening program. In low-resource countries, incorporating community-based self-sampling into screening programs might improve coverage of high-risk women. © 2017 International Federation of Gynecology and Obstetrics.

  10. Improving your Hypothesis Testing: Determining Sample Sizes.

    Science.gov (United States)

    Luftig, Jeffrey T.; Norton, Willis P.

    1982-01-01

    This article builds on an earlier discussion of the importance of the Type II error (beta) and power to the hypothesis testing process (CE 511 484), and illustrates the methods by which sample size calculations should be employed so as to improve the research process. (Author/CT)

  11. New immunochemical fecal occult blood test with two-consecutive stool sample testing is a cost-effective approach for colon cancer screening: results of a prospective multicenter study in Chinese patients.

    Science.gov (United States)

    Li, Shirong; Wang, Huahong; Hu, Jichun; Li, Nan; Liu, Yulan; Wu, Zitao; Zheng, Yue; Wang, Honghua; Wu, Kai; Ye, Hui; Rao, Jianyu

    2006-06-15

    The purpose of the study is to evaluate a new immunochemical fecal occult blood test method (Hemosure IFOBT), and compare it to the Guaiac-based chemical method (CFOBT) for colorectal cancer detection. A hypothetical sequential method (SFOBT), in which IFOBT was used only as a confirmatory test for CFOBT, was also evaluated. A total of 324 patients were recruited from 5 major hospitals in Beijing, China. For each patient, 3 consecutive stool samples were collected for simultaneous CFOBT and IFOBT tests, followed by colonoscopic examination. We compared the sensitivity and specificity of the 3 methods (CFOBT, IFOBT and SFOBT) in two settings, with the first 2 consecutive samples versus all 3 samples. Although the sensitivity for the detection of cancer and large (>20 mm) or multiple adenoma was similar for all 3 methods in the three-sample setting, in the two-sample setting IFOBT had higher sensitivity than SFOBT for detecting cancer (87.8% vs. 75.5%, respectively, p 20 mm) or multiple adenomas (65.4% vs. 42.3%, respectively, p < 0.05). The IFOBT also had a higher specificity than the CFOBT (89.2% vs. 75.5%, respectively, p < 0.01) in "normal" individuals defined by colonoscopy in the three-sample setting. Comparing two-sample setting to the three-sample setting, both CFOBT and SFOBT showed significant loss of sensitivity for the detection of cancer as well as adenoma, whereas the sensitivity for IFOBT did not change significantly. Overall, IFOBT with two-sample testing showed compatible sensitivity and specificity to the three-sample testing, and had a lower relative cost per cancer detected than the three-sample testing. In conclusion, the new Hemosure IFOBT with two consecutive stool samples appears to be the most cost-effective approach for colon cancer screening. Copyright 2006 Wiley-Liss, Inc.

  12. Experimental Investigation of Microbially Induced Corrosion of Test Samples and Effect of Self-Assembled Hydrophobic Monolayers. Exposure of Test Samples to Continuous Microbial Cultures, Chemical Analysis, and Biochemical Studies

    Energy Technology Data Exchange (ETDEWEB)

    Laurinavichius, K.S.

    1998-09-30

    The study of biocorrosion of aluminum and beryllium samples were performed under conditions of continuous fermentation of thermophilic anaerobic microorganisms of different groups. This allowed us to examine the effect of various types of metabolic reactions of reduction-oxidation proceeding at different pH and temperatures under highly reduced conditions on aluminum and beryllium corrosion and effect of self-assembled hydrophobic monolayers.

  13. Computing power and sample size for case-control association studies with copy number polymorphism: application of mixture-based likelihood ratio test.

    Directory of Open Access Journals (Sweden)

    Wonkuk Kim

    Full Text Available Recent studies suggest that copy number polymorphisms (CNPs may play an important role in disease susceptibility and onset. Currently, the detection of CNPs mainly depends on microarray technology. For case-control studies, conventionally, subjects are assigned to a specific CNP category based on the continuous quantitative measure produced by microarray experiments, and cases and controls are then compared using a chi-square test of independence. The purpose of this work is to specify the likelihood ratio test statistic (LRTS for case-control sampling design based on the underlying continuous quantitative measurement, and to assess its power and relative efficiency (as compared to the chi-square test of independence on CNP counts. The sample size and power formulas of both methods are given. For the latter, the CNPs are classified using the Bayesian classification rule. The LRTS is more powerful than this chi-square test for the alternatives considered, especially alternatives in which the at-risk CNP categories have low frequencies. An example of the application of the LRTS is given for a comparison of CNP distributions in individuals of Caucasian or Taiwanese ethnicity, where the LRTS appears to be more powerful than the chi-square test, possibly due to misclassification of the most common CNP category into a less common category.

  14. DOE/DOT Crude Oil Characterization Research Study, Task 2 Test Report on Evaluating Crude Oil Sampling and Analysis Methods

    Energy Technology Data Exchange (ETDEWEB)

    Lord, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Allen, Ray [Allen Energy Services, Inc., Longview, TX (United States); Rudeen, David [GRAM, Inc., Albuquerque, NM (United States)

    2017-11-01

    The Crude Oil Characterization Research Study is designed to evaluate whether crude oils currently transported in North America, including those produced from "tight" formations, exhibit physical or chemical properties that are distinct from conventional crudes, and how these properties associate with combustion hazards with may be realized during transportation and handling.

  15. Laboratory Studies of Technological Strength of Heat-Resistant Steels 15H1N1F Using the Small Sample Tests with Artificial Cooling

    Directory of Open Access Journals (Sweden)

    V. S. Drizhov

    2015-01-01

    Full Text Available The aim of the work is to develop a technique to research a damage of the welded structures from thermostable steels under reiterated heating.Damage of welded structures under reiterated heating depends on numerous processes, proceeding both in welding and under reiterated heating. This circumstance makes it necessary to analyze the reasons and conditions of emerging damage on the basis of numerous statistical materials. This problem can be solved only if simple and effective research methods are used to conduct tests.The paper uses theoretical and experimental methods of research. Theoretical researches are based on the calculation analysis of proceeding internal welding stresses in the welded structures from thermostable steels. For analysis the calculation method of solving a problem was applied taking into account heterogeneity of phase dilatation in different zones of the welded structure.Experimental researches were conducted on the small welded samples in conditions of isothermal relaxation of stresses. Using the artificial heat sink, when welding is a feature of these researches. These welding conditions allowed us to reproduce thermal cycles of welding on small samples, taking place in welding of the thick-walled welded units. Experimental researches of metal damage nature of the welded structures under reiterated heating were conducted on the welded samples, which were welded both by non-consumable electrode and by consumable one. In analysis the influence of stress concentrator on emerging damage was also taken into account.As a result of research a technique has been offered to study damage of welded structures under reiterated heating on the small samples used for tests.The metallography analysis of the metal damage nature of welded structures at small sample tests confirmed damage identity at tests and in practice during heat treatment of weldments from thermostable steels.The conducted experimental analysis of emerging damage

  16. Phoenix Test Sample Site in Color

    Science.gov (United States)

    2008-01-01

    This color image, acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on Sol 7, the seventh day of the mission (June 1, 2008), shows the so-called 'Knave of Hearts' first-dig test area to the north of the lander. The Robotic Arm's scraping blade left a small horizontal depression above where the sample was taken. Scientists speculate that white material in the depression left by the dig could represent ice or salts that precipitated into the soil. This material is likely the same white material observed in the sample in the Robotic Arm's scoop. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  17. Prostate specific antigen testing is associated with men's psychological and physical health and their healthcare utilisation in a nationally representative sample: a cross-sectional study.

    Science.gov (United States)

    Flahavan, Evelyn M; Drummond, Frances J; Bennett, Kathleen; Barron, Thomas I; Sharp, Linda

    2014-06-17

    Prostate cancer incidence has risen considerably in recent years, primarily due to Prostate Specific Antigen (PSA) testing in primary care. The objective of this study was to investigate associations between PSA testing and the psychological and physical health, and healthcare utilisation of men in a population where PSA testing is widespread. A cross-sectional study was carried out in a population-representative sample of men ≥ 50 years enrolled in The Irish Longitudinal Study on Ageing (TILDA). TILDA participants underwent structured interviews, health assessments and completed standardised questionnaires. Men were classified as ever/never having received a PSA test. Multivariate logistic regression (Odds Ratios (OR) and 95% Confidence Intervals (CI) was used to determine associations between PSA testing, and men's psychological and physical health and healthcare utilisation. This analysis included 3,628 men, 68.2% of whom ever had a PSA test. In adjusted analysis, men with sub-threshold depression were significantly less likely to have had a PSA test, (OR=0.79, 95% CI 0.64-0.97). Likelihood of having a PSA test was inversely associated with anxiety, but this was not significant (OR=0.79, 95% CI 0.57-1.09). Frailty (OR=0.61, 95% CI 0.31-1.05) and eligibility for free primary care (OR=0.63, 95% CI 0.52-0.77) were also inversely associated with PSA testing. Positive associations were observed between PSA testing and more chronic illnesses (OR=1.11, 95% CI 1.05-1.19), more primary care visits (OR=1.03, 95% CI 1.01-1.05) and preventative health practices, including cholesterol testing and influenza vaccination (OR=1.35, 95% CI 1.13-1.60). Men's psychological and physical health and their healthcare utilisation are associated with PSA testing in primary care. The association between poorer psychological health, in particular sub-threshold depression, and reduced likelihood of PSA testing in primary care requires further investigation. These findings may have wider

  18. The Utility of IRT in Small-Sample Testing Applications.

    Science.gov (United States)

    Sireci, Stephen G.

    The utility of modified item response theory (IRT) models in small sample testing applications was studied. The modified IRT models were modifications of the one- and two-parameter logistic models. One-, two-, and three-parameter models were also studied. Test data were from 4 years of a national certification examination for persons desiring…

  19. An interlaboratory study as useful tool for proficiency testing of chemical oxygen demand measurements using solid substrates and liquid samples with high suspended solid content.

    Science.gov (United States)

    Raposo, F; de la Rubia, M A; Borja, R; Alaiz, M; Beltrán, J; Cavinato, C; Clinckspoor, M; Demirer, G; Diamadopoulos, E; Helmreich, B; Jenicek, P; Martí, N; Méndez, R; Noguerol, J; Pereira, F; Picard, S; Torrijos, M

    2009-11-15

    In 2008, the first Proficiency Testing Scheme of Chemical Oxygen Demand (1(st)COD-PT(ADG)) was conducted to assess the results obtained for different research groups whose field work is mainly anaerobic digestion. This study was performed using four samples, two solid samples as raw materials and two solid samples to prepare high concentration suspended solid solutions. Invitations were sent to a large number of laboratories, mainly to anaerobic digestion research groups. Finally, thirty labs from sixteen countries agreed to participate, but for different reasons four participants could not send any data. In total, twenty-six results were reported to the COD-PT coordinator. This study showed the importance of continuous participation in proficiency testing (PT) schemes in order to compare the results obtained. Taking into account the lack of a general standard method and high quality certified reference materials (CRMs), the traceability of COD determination is not currently easy to check. In addition, the spread of participants' results obtained was high and pointed to the advisability of using consensus values due to their unreliability. Therefore, the theoretical oxygen demand (ThOD) values were considered as assigned values for all the samples analysed. On the other hand, in this PT the established standard deviation (ESD) has been determined by the Horwitz modified function. Participants of this 1(st)COD-PT(ADG) were asked to give a short report on the analytical method used. Although all the participants used potassium dichromate as their oxidant reagent, their experimental procedures were very different. With the purpose of comparing the results obtained, the different experimental conditions used were classified into five methods, corresponding to two main categories, open and closed reflux. The performance of laboratories was expressed by the z-score, whose value is considered satisfactory when z-score

  20. Age-at-death estimation by pulp/tooth area ratio in canines: study of a 20th-century Mexican sample of prisoners to test Cameriere's method.

    Science.gov (United States)

    De Luca, Stefano; Bautista, Josefina; Alemán, Inmaculada; Cameriere, Roberto

    2011-09-01

    Accurate age estimation has always been a problem for forensic scientists, and apposition of secondary dentine is often used as an indicator of age. Cameriere et al. studied the pulp/tooth area ratio by peri-apical X-ray images of the canines, to observe the apposition of secondary dentine. The present study examines the application of this technique in a Mexican identified sample coming from the Department of Physical Anthropology of the INAH, at Mexico City. The main aim of this work is to test the reliability of this method in a skeletal sample of a specific population, different from the samples used for its development. The obtained regression model explained 96.2% of total variance (R(2) = 0.962) with a standard error of estimate of 1.909 and a standard deviation of 1.947. These results demonstrate great reliability and that the age/secondary dentine relationship is not variable in this specific population. © 2011 American Academy of Forensic Sciences.

  1. Experimental and Sampling Design for the INL-2 Sample Collection Operational Test

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.; Amidan, Brett G.; Matzke, Brett D.

    2009-02-16

    , sample extraction, and analytical methods to be used in the INL-2 study. For each of the five test events, the specified floor of the INL building will be contaminated with BG using a point-release device located in the room specified in the experimental design. Then quality control (QC), reference material coupon (RMC), judgmental, and probabilistic samples will be collected according to the sampling plan for each test event. Judgmental samples will be selected based on professional judgment and prior information. Probabilistic samples were selected with a random aspect and in sufficient numbers to provide desired confidence for detecting contamination or clearing uncontaminated (or decontaminated) areas. Following sample collection for a given test event, the INL building will be decontaminated. For possibly contaminated areas, the numbers of probabilistic samples were chosen to provide 95% confidence of detecting contaminated areas of specified sizes. For rooms that may be uncontaminated following a contamination event, or for whole floors after decontamination, the numbers of judgmental and probabilistic samples were chosen using the CJR approach. The numbers of samples were chosen to support making X%/Y% clearance statements with X = 95% or 99% and Y = 96% or 97%. The experimental and sampling design also provides for making X%/Y% clearance statements using only probabilistic samples. For each test event, the numbers of characterization and clearance samples were selected within limits based on operational considerations while still maintaining high confidence for detection and clearance aspects. The sampling design for all five test events contains 2085 samples, with 1142 after contamination and 943 after decontamination. These numbers include QC, RMC, judgmental, and probabilistic samples. The experimental and sampling design specified in this report provides a good statistical foundation for achieving the objectives of the INL-2 study.

  2. Testing of Small Graphite Samples for Nuclear Qualification

    Energy Technology Data Exchange (ETDEWEB)

    Julie Chapman

    2010-11-01

    Accurately determining the mechanical properties of small irradiated samples is crucial to predicting the behavior of the overal irradiated graphite components within a Very High Temperature Reactor. The sample size allowed in a material test reactor, however, is limited, and this poses some difficulties with respect to mechanical testing. In the case of graphite with a larger grain size, a small sample may exhibit characteristics not representative of the bulk material, leading to inaccuracies in the data. A study to determine a potential size effect on the tensile strength was pursued under the Next Generation Nuclear Plant program. It focuses first on optimizing the tensile testing procedure identified in the American Society for Testing and Materials (ASTM) Standard C 781-08. Once the testing procedure was verified, a size effect was assessed by gradually reducing the diameter of the specimens. By monitoring the material response, a size effect was successfully identified.

  3. Experimental Design for the INL Sample Collection Operational Test

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G.; Piepel, Gregory F.; Matzke, Brett D.; Filliben, James J.; Jones, Barbara

    2007-12-13

    This document describes the test events and numbers of samples comprising the experimental design that was developed for the contamination, decontamination, and sampling of a building at the Idaho National Laboratory (INL). This study is referred to as the INL Sample Collection Operational Test. Specific objectives were developed to guide the construction of the experimental design. The main objective is to assess the relative abilities of judgmental and probabilistic sampling strategies to detect contamination in individual rooms or on a whole floor of the INL building. A second objective is to assess the use of probabilistic and Bayesian (judgmental + probabilistic) sampling strategies to make clearance statements of the form “X% confidence that at least Y% of a room (or floor of the building) is not contaminated. The experimental design described in this report includes five test events. The test events (i) vary the floor of the building on which the contaminant will be released, (ii) provide for varying or adjusting the concentration of contaminant released to obtain the ideal concentration gradient across a floor of the building, and (iii) investigate overt as well as covert release of contaminants. The ideal contaminant gradient would have high concentrations of contaminant in rooms near the release point, with concentrations decreasing to zero in rooms at the opposite end of the building floor. For each of the five test events, the specified floor of the INL building will be contaminated with BG, a stand-in for Bacillus anthracis. The BG contaminant will be disseminated from a point-release device located in the room specified in the experimental design for each test event. Then judgmental and probabilistic samples will be collected according to the pre-specified sampling plan. Judgmental samples will be selected based on professional judgment and prior information. Probabilistic samples will be selected in sufficient numbers to provide desired confidence

  4. Generation of test databases using sampling methods

    OpenAIRE

    Buda, Teodora Sandra

    2013-01-01

    peer-reviewed Populating the testing environment with relevant data represents a great challenge in software validation, generally requiring expert knowledge about the system under development, as its data critically impacts the outcome of the tests designed to assess the system. Current practices of populating the testing environments generally focus on developing e cient algorithms for generating synthetic data or use the production environment for testing purposes. ...

  5. Two-stage sampling for acceptance testing

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, C.L.; Bryan, M.F.

    1992-09-01

    Sometimes a regulatory requirement or a quality-assurance procedure sets an allowed maximum on a confidence limit for a mean. If the sample mean of the measurements is below the allowed maximum, but the confidence limit is above it, a very widespread practice is to increase the sample size and recalculate the confidence bound. The confidence level of this two-stage procedure is rarely found correctly, but instead is typically taken to be the nominal confidence level, found as if the final sample size had been specified in advance. In typical settings, the correct nominal [alpha] should be between the desired P(Type I error) and half that value. This note gives tables for the correct a to use, some plots of power curves, and an example of correct two-stage sampling.

  6. Two-stage sampling for acceptance testing

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, C.L.; Bryan, M.F.

    1992-09-01

    Sometimes a regulatory requirement or a quality-assurance procedure sets an allowed maximum on a confidence limit for a mean. If the sample mean of the measurements is below the allowed maximum, but the confidence limit is above it, a very widespread practice is to increase the sample size and recalculate the confidence bound. The confidence level of this two-stage procedure is rarely found correctly, but instead is typically taken to be the nominal confidence level, found as if the final sample size had been specified in advance. In typical settings, the correct nominal {alpha} should be between the desired P(Type I error) and half that value. This note gives tables for the correct a to use, some plots of power curves, and an example of correct two-stage sampling.

  7. Sample Size Determination for Rasch Model Tests

    Science.gov (United States)

    Draxler, Clemens

    2010-01-01

    This paper is concerned with supplementing statistical tests for the Rasch model so that additionally to the probability of the error of the first kind (Type I probability) the probability of the error of the second kind (Type II probability) can be controlled at a predetermined level by basing the test on the appropriate number of observations.…

  8. Sample size in usability studies

    NARCIS (Netherlands)

    Schmettow, Martin

    2012-01-01

    Usability studies are important for developing usable, enjoyable products, identifying design flaws (usability problems) likely to compromise the user experience. Usability testing is recommended for improving interactive design, but discovery of usability problems depends on the number of users

  9. Testing the Double-Deficit Hypothesis in an Adult Sample

    Science.gov (United States)

    Miller, Carlin J.; Miller, Scott R.; Bloom, Juliana S.; Jones, Lauren; Lindstrom, William; Craggs, Jason; Garcia-Barrera, Mauricio; Semrud-Clikeman, Margaret; Gilger, Jeffrey W.; Hynd, George W.

    2006-01-01

    The double-deficit hypothesis of dyslexia posits that reading deficits are more severe in individuals with weaknesses in phonological awareness and rapid naming than in individuals with deficits in only one of these reading composite skills. In this study, the hypothesis was tested in an adult sample as a model of reading achievement. Participants…

  10. [Homologous amelogenin gene test of archaeological samples].

    Science.gov (United States)

    Zhang, Hu-Qin; Yang, Zhou-Qi; Liu, Fang-E; Zhang, Jin; Zhao, Wen-Ming

    2006-06-01

    Based on the sequence differences of Amelogenin homologous gene in the X and Y chromosomes, a pair of specific primers was designed to identify the sex of archaeological samples. Ancient DNA fragments were extracted from the bones and teeth of sacrificial slaves with an improved method that combines phenol-chloroform extraction, silicon dioxide adsorption with ultrafiltration concentration. The polyacrylamide gel electrophoresis (PAGE) was used to detect PCR products. Seven in sixteen samples from eight graves showed positive results and the targeted segments were visible: a male with two bands of 106bp (Amel-X) and 112 bp (Amel-Y), while a female with only one band of 106 bp (Amel-X). Ancient DNA analyzing results from tooth samples are more marked than that from bones. The improved extraction method is more effective for ancient DNA extraction, which reduced the PCR inhibitors and lowered experimental costs. The sex determination technology based on Amelogenin homologous gene is an important and feasible method in the molecular archaeological research.

  11. Collection and Testing of Respiratory Samples

    Science.gov (United States)

    2017-04-03

    QIAGEN ResPlex II Advanced Panel; Influenza A; Respiratory Syncytial Virus Infections; Infection Due to Human Parainfluenza Virus 1; Parainfluenza Type 2; Parainfluenza Type 3; Parainfluenza Type 4; Human Metapneumovirus A/B; Rhinovirus; Coxsackie Virus/Echovirus; Adenovirus Types B/C/E; Coronavirus Subtypes 229E; Coronavirus Subtype NL63; Coronavirus Subtype OC43; Coronavirus Subtype HKU1; Human Bocavirus; Artus Influenza A/B RT-PCR Test; Influenza B

  12. Testing Homogeneity in a Semiparametric Two-Sample Problem

    Directory of Open Access Journals (Sweden)

    Yukun Liu

    2012-01-01

    Full Text Available We study a two-sample homogeneity testing problem, in which one sample comes from a population with density f(x and the other is from a mixture population with mixture density (1−λf(x+λg(x. This problem arises naturally from many statistical applications such as test for partial differential gene expression in microarray study or genetic studies for gene mutation. Under the semiparametric assumption g(x=f(xeα+βx, a penalized empirical likelihood ratio test could be constructed, but its implementation is hindered by the fact that there is neither feasible algorithm for computing the test statistic nor available research results on its theoretical properties. To circumvent these difficulties, we propose an EM test based on the penalized empirical likelihood. We prove that the EM test has a simple chi-square limiting distribution, and we also demonstrate its competitive testing performances by simulations. A real-data example is used to illustrate the proposed methodology.

  13. Bender Gestalt Visual-Motor test – Sistema de Pontuação Gradual (B-SPG: A study with different samples

    Directory of Open Access Journals (Sweden)

    Ana Paula Porto Noronha

    2013-05-01

    Full Text Available The aim in this study was to analyze differences between children’s performances on the Bender – Sistema de Pontuação Gradual (B-SPG [Gradual Scoring System] in the states of Minas Gerais and Paraíba, and to compare them with the results presented in the test manual. The participants were 511 children, both sexes, aged 6-10 years ( M = 8.21, SD = 1.33, and 50.7% male. The children were from two states, Minas Gerais ( n = 298, 58.3% and Paraiba ( n = 213, 41.7%. The SPG was administered collectively in classrooms. The mean B-SPG scores between the children from Minas Gerais and Paraiba were very similar and not statistically significant. Regarding the comparison between the two states and the normative sample, three results were significant, two of which favored the children from São Paulo and the other the children from Minas Gerais and Paraíba, showing little variation in the results of the B-SPG.

  14. Validation of the Alcohol Use Disorders Identification Test and the Drug Use Disorders Identification Test in a Swedish sample of suspected offenders with signs of mental health problems: results from the Mental Disorder, Substance Abuse and Crime study.

    Science.gov (United States)

    Durbeej, Natalie; Berman, Anne H; Gumpert, Clara H; Palmstierna, Tom; Kristiansson, Marianne; Alm, Charlotte

    2010-12-01

    Substance abuse is common among offenders. One method widely used for the detection of substance abuse is screening. This study explored the concurrent validity of the Alcohol Use Disorders Identification Test (AUDIT) and the Drug Use Disorders Identification Test (DUDIT) screening tools in relation to (a) substance abuse and dependency diagnoses and (b) three problem severity domains of the sixth version of the Addiction Severity Index in a sample of 181 suspected offenders with signs of mental health problems. The screening tools showed moderate to high accuracy for identification of dependency diagnoses. The AUDIT was associated with alcohol problem severity, whereas the DUDIT was associated with drug and legal problem severity. Administering the screening tools in the current population yields valid results. However, the suggested cutoff scores should be applied with caution due to the discrepancy between present and previous findings. Copyright © 2010 Elsevier Inc. All rights reserved.

  15. Revision of the SNPforID 34-plex forensic ancestry test: Assay enhancements, standard reference sample genotypes and extended population studies.

    Science.gov (United States)

    Fondevila, M; Phillips, C; Santos, C; Freire Aradas, A; Vallone, P M; Butler, J M; Lareu, M V; Carracedo, A

    2013-01-01

    A revision of an established 34 SNP forensic ancestry test has been made by swapping the under-performing rs727811 component SNP with the highly informative rs3827760 that shows a near-fixed East Asian specific allele. We collated SNP variability data for the revised SNP set in 66 reference populations from 1000 Genomes and HGDP-CEPH panels and used this as reference data to analyse four U.S. populations showing a range of admixture patterns. The U.S. Hispanics sample in particular displayed heterogeneous values of co-ancestry between European, Native American and African contributors, likely to reflect in part, the way this disparate group is defined using cultural as well as population genetic parameters. The genotyping of over 700 U.S. population samples also provided the opportunity to thoroughly gauge peak mobility variation and peak height ratios observed from routine use of the single base extension chemistry of the 34-plex test. Finally, the genotyping of the widely used DNA profiling Standard Reference Material samples plus other control DNAs completes the audit of the 34-plex assay to allow forensic practitioners to apply this test more readily in their own laboratories. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  16. 40 CFR 205.171-3 - Test motorcycle sample selection.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Test motorcycle sample selection. 205... ABATEMENT PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycle Exhaust Systems § 205.171-3 Test motorcycle sample selection. A test motorcycle to be used for selective enforcement audit testing...

  17. A nonparametric significance test for sampled networks.

    Science.gov (United States)

    Elliott, Andrew; Leicht, Elizabeth; Whitmore, Alan; Reinert, Gesine; Reed-Tsochas, Felix

    2018-01-01

    Our work is motivated by an interest in constructing a protein-protein interaction network that captures key features associated with Parkinson's disease. While there is an abundance of subnetwork construction methods available, it is often far from obvious which subnetwork is the most suitable starting point for further investigation. We provide a method to assess whether a subnetwork constructed from a seed list (a list of nodes known to be important in the area of interest) differs significantly from a randomly generated subnetwork. The proposed method uses a Monte Carlo approach. As different seed lists can give rise to the same subnetwork, we control for redundancy by constructing a minimal seed list as the starting point for the significance test. The null model is based on random seed lists of the same length as a minimum seed list that generates the subnetwork; in this random seed list the nodes have (approximately) the same degree distribution as the nodes in the minimum seed list. We use this null model to select subnetworks which deviate significantly from random on an appropriate set of statistics and might capture useful information for a real world protein-protein interaction network. The software used in this paper are available for download at https://sites.google.com/site/elliottande/. The software is written in Python and uses the NetworkX library. ande.elliott@gmail.com or felix.reed-tsochas@sbs.ox.ac.uk. Supplementary data are available at Bioinformatics online.

  18. Normative reference values for the 20 m shuttle‐run test in a population‐based sample of school‐aged youth in Bogota, Colombia: the FUPRECOL study

    Science.gov (United States)

    Palacios‐López, Adalberto; Humberto Prieto‐Benavides, Daniel; Enrique Correa‐Bautista, Jorge; Izquierdo, Mikel; Alonso‐Martínez, Alicia; Lobelo, Felipe

    2016-01-01

    Abstract Objectives Our aim was to determine the normative reference values of cardiorespiratory fitness (CRF) and to establish the proportion of subjects with low CRF suggestive of future cardio‐metabolic risk. Methods A total of 7244 children and adolescents attending public schools in Bogota, Colombia (55.7% girls; age range of 9–17.9 years) participated in this study. We expressed CRF performance as the nearest stage (minute) completed and the estimated peak oxygen consumption (V˙O2peak). Smoothed percentile curves were calculated. In addition, we present the prevalence of low CRF after applying a correction factor to account for the impact of Bogota's altitude (2625 m over sea level) on CRF assessment, and we calculated the number of participants who fell below health‐related FITNESSGRAM cut‐points for low CRF. Results Shuttles and V˙O2peak were higher in boys than in girls in all age groups. In boys, there were higher levels of performance with increasing age, with most gains between the ages of 13 and 17. The proportion of subjects with a low CRF, suggestive of future cardio‐metabolic risk (health risk FITNESSGRAM category) was 31.5% (28.2% for boys and 34.1% for girls; X2 P = .001). After applying a 1.11 altitude correction factor, the overall prevalence of low CRF was 11.5% (9.6% for boys and 13.1% for girls; X2 P = .001). Conclusions Our results provide sex‐ and age‐specific normative reference standards for the 20 m shuttle‐run test and estimated V˙O2peak values in a large, population‐based sample of schoolchildren from a large Latin‐American city at high altitude. PMID:27500986

  19. Normative reference values for the 20 m shuttle-run test in a population-based sample of school-aged youth in Bogota, Colombia: the FUPRECOL study.

    Science.gov (United States)

    Ramírez-Vélez, Robinson; Palacios-López, Adalberto; Humberto Prieto-Benavides, Daniel; Enrique Correa-Bautista, Jorge; Izquierdo, Mikel; Alonso-Martínez, Alicia; Lobelo, Felipe

    2017-01-01

    Our aim was to determine the normative reference values of cardiorespiratory fitness (CRF) and to establish the proportion of subjects with low CRF suggestive of future cardio-metabolic risk. A total of 7244 children and adolescents attending public schools in Bogota, Colombia (55.7% girls; age range of 9-17.9 years) participated in this study. We expressed CRF performance as the nearest stage (minute) completed and the estimated peak oxygen consumption (V˙O2peak ). Smoothed percentile curves were calculated. In addition, we present the prevalence of low CRF after applying a correction factor to account for the impact of Bogota's altitude (2625 m over sea level) on CRF assessment, and we calculated the number of participants who fell below health-related FITNESSGRAM cut-points for low CRF. Shuttles and V˙O2peak were higher in boys than in girls in all age groups. In boys, there were higher levels of performance with increasing age, with most gains between the ages of 13 and 17. The proportion of subjects with a low CRF, suggestive of future cardio-metabolic risk (health risk FITNESSGRAM category) was 31.5% (28.2% for boys and 34.1% for girls; X2 P = .001). After applying a 1.11 altitude correction factor, the overall prevalence of low CRF was 11.5% (9.6% for boys and 13.1% for girls; X2 P = .001). Our results provide sex- and age-specific normative reference standards for the 20 m shuttle-run test and estimated V˙O2peak values in a large, population-based sample of schoolchildren from a large Latin-American city at high altitude. © 2016 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc.

  20. Can health workers reliably assess their own work? A test-retest study of bias among data collectors conducting a Lot Quality Assurance Sampling survey in Uganda.

    Science.gov (United States)

    Beckworth, Colin A; Davis, Rosemary H; Faragher, Brian; Valadez, Joseph J

    2015-03-01

    Lot Quality Assurance Sampling (LQAS) is a classification method that enables local health staff to assess health programmes for which they are responsible. While LQAS has been favourably reviewed by the World Bank and World Health Organization (WHO), questions remain about whether using local health staff as data collectors can lead to biased data. In this test-retest research, Pallisa Health District in Uganda is subdivided into four administrative units called supervision areas (SA). Data collectors from each SA conducted an LQAS survey. A week later, the data collectors were swapped to a different SA, outside their area of responsibility, to repeat the LQAS survey with the same respondents. The two data sets were analysed for agreement using Cohens' kappa coefficient and disagreements were analysed. Kappa values ranged from 0.19 to 0.97. On average, there was a moderate degree of agreement for knowledge indicators and a substantial level for practice indicators. Respondents were found to be systematically more knowledgeable on retest indicating bias favouring the retest, although no evidence of bias was found for practices indicators. In this initial study, using local health care providers to collect data did not bias data collection. The bias observed in the knowledge indicators is most likely due to the 'practice effect', whereby respondents increased their knowledge as a result of completing the first survey, as no corresponding effect was seen in the practices indicators. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine © The Author 2014; all rights reserved.

  1. Regeneration Study Test Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data (2 excel files) consist of the analytical test results on water sample collected from the two adsorption media tanks of the arsenic removal system during the...

  2. Apparatus for testing skin samples or the like

    Science.gov (United States)

    Holland, J.M.

    1982-08-31

    An apparatus for testing the permeability of living skin samples has a flat base with a plurality of sample-holding cavities formed in its upper surface, the samples being placed in counterbores in the cavities with the epidermis uppermost. O-rings of Teflon washers are respectively placed on the samples and a flat cover is connected to the base to press the rings against the upper surfaces of the samples. Media to maintain tissue viability and recovery of metabolites is introduced into the lower portion of the sample-holding cavities through passages in the base. Test materials are introduced through holes in the cover plate after assembly of the chamber.

  3. Statistical sampling and hypothesis testing in orthopaedic research.

    Science.gov (United States)

    Bernstein, Joseph; McGuire, Kevin; Freedman, Kevin B

    2003-08-01

    The purpose of the current article was to review the process of hypothesis testing and statistical sampling and empower readers to critically appraise the literature. When the p value of a study lies above the alpha threshold, the results are said to be not statistically significant. It is possible, however, that real differences do exist, but the study was insufficiently powerful to detect them. In that case, the conclusion that two groups are equivalent is wrong. The probability of this mistake, the Type II error, is given by the beta statistic. The complement of beta, or 1-beta, representing the chance of avoiding a Type II error, is termed the statistical power of the study. We previously examined the statistical power and sample size in all of the studies published in 1997 in the American and British volumes of the Journal of Bone and Joint Surgery, and in Clinical Orthopaedics and Related Research. In the journals examined, only 3% of studies had adequate statistical power to detect a small effect size in this sample. In addition, a study examining only randomized control trials in these journals showed that none of 25 randomized control trials had adequate statistical power to detect a small effect size. However, beta, or power, is less well understood. Because of this, researchers and readers should be aware of the need to address issues of statistical power before a study begins and be cautious of studies that conclude that no difference exists between groups.

  4. Operability test report for the in SITU vapor sampling

    Energy Technology Data Exchange (ETDEWEB)

    Corbett, J.E., Westinghouse Hanford

    1996-05-31

    This report documents the successful completion of testing for the In Situ Vapor Sampling (ISVS) system. The report includes the test procedure (WHC-SD-WM-OTP-196, Rev OA), data sheets, exception resolutions, and a test report summary. This report conforms to the guidelines established in WHC-IP-1026, `Engineering Practice Guidelines,` Appendix L, `Operability Test Procedures and Reports.`

  5. Method of determining an electrical property of a test sample

    DEFF Research Database (Denmark)

    2010-01-01

    A method of obtaining an electrical property of a test sample, comprising a non-conductive area and a conductive or semi-conductive test area, byperforming multiple measurements using a multi-point probe. The method comprising the steps of providing a magnetic field having field lines passing...... the electrical property of the test area....

  6. Testing K. Patrick Method of Psychopathy Diagnosis in Russian Sample

    Directory of Open Access Journals (Sweden)

    Atadzhykova Y.A.,

    2015-12-01

    Full Text Available The article is devoted to the development of a method of diagnosing psychopathy, or antisocial (dissocial personality disorder. Modern researchers mostly use the methods of experiment, expert assessment, clinical interview or different combinations for personality disorders, including psychopathy. However, nowadays there is a growing need in development of a psychopathy diagnosis method which would be less labour-intensive, less expensive and more objective. One of the recently developed models of psychopathy is Trierarchic conceptualization by C. Patrick, it offers a new way to operationalize and diagnose psychopathy. The authors had tested this method in the Russian population, including both common sample as well as criminal offender sample consisting of individuals that have been suspected, accused or convicted of violent crimes. The subject of the current research is psychopathic traits measured by the tested method. We had carried out statistical and content analyzes of the data. Our study allowed to conclude that tested Russian version of the Triarchic Psychopathy Measure is effective enough to be used for research purposes. However, further research is required in order to render this measure valid to practical use.

  7. Acceptance test report for core sample trucks 3 and 4

    Energy Technology Data Exchange (ETDEWEB)

    Corbett, J.E.

    1996-04-10

    The purpose of this Acceptance Test Report is to provide documentation for the acceptance testing of the rotary mode core sample trucks 3 and 4, designated as HO-68K-4600 and HO-68K-4647, respectively. This report conforms to the guidelines established in WHC-IP-1026, ``Engineering Practice Guidelines,`` Appendix M, ``Acceptance Test Procedures and Reports.`` Rotary mode core sample trucks 3 and 4 were based upon the design of the second core sample truck (HO-68K-4345) which was constructed to implement rotary mode sampling of the waste tanks at Hanford. Successful completion of acceptance testing on June 30, 1995 verified that all design requirements were met. This report is divided into four sections, beginning with general information. Acceptance testing was performed on trucks 3 and 4 during the months of March through June, 1995. All testing was performed at the ``Rock Slinger`` test site in the 200 West area. The sequence of testing was determined by equipment availability, and the initial revision of the Acceptance Test Procedure (ATP) was used for both trucks. Testing was directed by ICF-KH, with the support of WHC Characterization Equipment Engineering and Characterization Project Operations. Testing was completed per the ATP without discrepancies or deviations, except as noted.

  8. Impact of different storage times at room temperature of unspun citrated blood samples on routine coagulation tests results. Results of a bicenter study and review of the literature.

    Science.gov (United States)

    Toulon, P; Metge, S; Hangard, M; Zwahlen, S; Piaulenne, S; Besson, V

    2017-10-01

    A maximum delay between blood collection and coagulation testing of 4 hours is recommended by most guidelines. As information on optimal storage times is limited, we investigated the potential effect of different storage times of unspun tubes, that is, ≤2, 4, 6, and 8 hours, on routine coagulation test results. Four evacuated polymer tubes containing 0.109 mol/L tri-Na citrate were drawn from 144 patients, including 39 patients on vitamin K-antagonists. Except for storage time, all tubes underwent the same preanalytical process. Prothrombin time (PT)/international normalized ratio (INR), activated partial thromboplastin time (aPTT), fibrinogen, factor V (FV), FVIII, and D-dimer were evaluated in two centers using the same technical conditions. Analytical comparison of aPTT, fibrinogen, FV, and FVIII results evaluated after prolonged storage times vs a <2-hours storage demonstrated significant difference, whereas PT/INR and D-dimer remained unchanged up to 8 hours. Mean bias between test results obtained after prolonged storage times remained below the desirable values for all studied parameters except for FVIII evaluated after 6- and 8-hours storages, but only in patients with FVIII above 100 IU/dL. Even though the corresponding bias of -5.2% and -8.5%, respectively, remained within the GEHT recommended limits of variation, its evaluation after an 8-hours storage could lead to significant underestimation of FVIII. These results suggest that, in the studied technical conditions, PT/INR, aPTT, fibrinogen, FV, and D-dimer can be reliably evaluated in tubes stored unspun at room temperature for up to 8 hours after blood collection. That optimal delay should be of 6 hours for FVIII. © 2017 The Authors. International Journal of Laboratory Hematology Published by John Wiley & Sons Ltd.

  9. Optimum sample size allocation to minimize cost or maximize power for the two-sample trimmed mean test.

    Science.gov (United States)

    Guo, Jiin-Huarng; Luh, Wei-Ming

    2009-05-01

    When planning a study, sample size determination is one of the most important tasks facing the researcher. The size will depend on the purpose of the study, the cost limitations, and the nature of the data. By specifying the standard deviation ratio and/or the sample size ratio, the present study considers the problem of heterogeneous variances and non-normality for Yuen's two-group test and develops sample size formulas to minimize the total cost or maximize the power of the test. For a given power, the sample size allocation ratio can be manipulated so that the proposed formulas can minimize the total cost, the total sample size, or the sum of total sample size and total cost. On the other hand, for a given total cost, the optimum sample size allocation ratio can maximize the statistical power of the test. After the sample size is determined, the present simulation applies Yuen's test to the sample generated, and then the procedure is validated in terms of Type I errors and power. Simulation results show that the proposed formulas can control Type I errors and achieve the desired power under the various conditions specified. Finally, the implications for determining sample sizes in experimental studies and future research are discussed.

  10. Cold Vacuum Drying Facility Stack Air Sampling System Qualification Tests

    Energy Technology Data Exchange (ETDEWEB)

    Glissmeyer, John A.

    2001-01-24

    This report documents tests that were conducted to verify that the air monitoring system for the Cold Vacuum Drying Facility ventilation exhaust stack meets the applicable regulatory criteria regarding the placement of the air sampling probe, sample transport, and stack flow measurement accuracy.

  11. Synthesizing Information from Language Samples and Standardized Tests in School-Age Bilingual Assessment

    Science.gov (United States)

    Ebert, Kerry Danahy; Pham, Giang

    2017-01-01

    Purpose: Although language samples and standardized tests are regularly used in assessment, few studies provide clinical guidance on how to synthesize information from these testing tools. This study extends previous work on the relations between tests and language samples to a new population--school-age bilingual speakers with primary language…

  12. FORTRAN implementation of Friedman's test for several related samples

    Science.gov (United States)

    Davidson, S. A.

    1982-01-01

    The FRIEDMAN program is a FORTRAN-coded implementation of Friedman's nonparametric test for several related samples with one observation per treatment/-block combination, or as it is sometimes called, the two-way analysis of variance by ranks. The FRIEDMAN program is described and a test data set and its results are presented to aid potential users of this program.

  13. 40 CFR 205.57-2 - Test vehicle sample selection.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Test vehicle sample selection. 205.57-2 Section 205.57-2 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Medium and Heavy Trucks § 205.57-2 Test...

  14. GICHD Mine Dog Testing Project - Soil Sample Results No.3

    Energy Technology Data Exchange (ETDEWEB)

    PHELAN, JAMES M.; BARNETT, JAMES L.; BENDER, SUSAN FAE ANN; ARCHULETA, LUISA M.

    2003-03-01

    A mine dog evaluation project initiated by the Geneva International Center for Humanitarian Demining is evaluating the capability and reliability of mine detection dogs. The performance of field-operational mine detection dogs will be measured in test minefields in Afghanistan and Bosnia containing actual, but unfused landmines. Repeated performance testing over two years through various seasonal weather conditions will provide data simulating near real world conditions. Soil samples will be obtained adjacent to the buried targets repeatedly over the course of the test. Chemical analysis results from these soil samples will be used to evaluate correlations between mine dog detection performance and seasonal weather conditions. This report documents the analytical chemical methods and results from the third batch of soils received. This batch contained samples from Kharga, Afghanistan collected in October 2002.

  15. GICHD mine dog testing project : soil sample results #5.

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, James L.; Phelan, James M.; Archuleta, Luisa M.; Donovan, Kelly L.; Bender, Susan Fae Ann

    2004-01-01

    A mine dog evaluation project initiated by the Geneva International Center for Humanitarian Demining is evaluating the capability and reliability of mine detection dogs. The performance of field-operational mine detection dogs will be measured in test minefields in Afghanistan containing actual, but unfused landmines. Repeated performance testing over two years through various seasonal weather conditions will provide data simulating near real world conditions. Soil samples will be obtained adjacent to the buried targets repeatedly over the course of the test. Chemical analysis results from these soil samples will be used to evaluate correlations between mine dog detection performance and seasonal weather conditions. This report documents the analytical chemical methods and results from the fifth batch of soils received. This batch contained samples from Kharga, Afghanistan collected in June 2003.

  16. GICHD mine dog testing project - soil sample results #4.

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, James L.; Phelan, James M.; Archuleta, Luisa M.; Wood, Tyson B.; Donovan, Kelly L.; Bender, Susan Fae Ann

    2003-08-01

    A mine dog evaluation project initiated by the Geneva International Center for Humanitarian Demining is evaluating the capability and reliability of mine detection dogs. The performance of field-operational mine detection dogs will be measured in test minefields in Afghanistan and Bosnia containing actual, but unfused landmines. Repeated performance testing over two years through various seasonal weather conditions will provide data simulating near real world conditions. Soil samples will be obtained adjacent to the buried targets repeatedly over the course of the test. Chemical analysis results from these soil samples will be used to evaluate correlations between mine dog detection performance and seasonal weather conditions. This report documents the analytical chemical methods and results from the fourth batch of soils received. This batch contained samples from Kharga, Afghanistan collected in April 2003 and Sarajevo, Bosnia collected in May 2003.

  17. CHARACTERIZATION AND ACTUAL WASTE TEST WITH TANK 5F SAMPLES

    Energy Technology Data Exchange (ETDEWEB)

    Hay, M. S.; Crapse, K. P.; Fink, S. D.; Pareizs, J. M.

    2007-08-30

    The initial phase of bulk waste removal operations was recently completed in Tank 5F. Video inspection of the tank indicates several mounds of sludge still remain in the tank. Additionally, a mound of white solids was observed under Riser 5. In support of chemical cleaning and heel removal programs, samples of the sludge and the mound of white solids were obtained from the tank for characterization and testing. A core sample of the sludge and Super Snapper sample of the white solids were characterized. A supernate dip sample from Tank 7F was also characterized. A portion of the sludge was used in two tank cleaning tests using oxalic acid at 50 C and 75 C. The filtered oxalic acid from the tank cleaning tests was subsequently neutralized by addition to a simulated Tank 7F supernate. Solids and liquid samples from the tank cleaning test and neutralization test were characterized. A separate report documents the results of the gas generation from the tank cleaning test using oxalic acid and Tank 5F sludge. The characterization results for the Tank 5F sludge sample (FTF-05-06-55) appear quite good with respect to the tight precision of the sample replicates, good results for the glass standards, and minimal contamination found in the blanks and glass standards. The aqua regia and sodium peroxide fusion data also show good agreement between the two dissolution methods. Iron dominates the sludge composition with other major contributors being uranium, manganese, nickel, sodium, aluminum, and silicon. The low sodium value for the sludge reflects the absence of supernate present in the sample due to the core sampler employed for obtaining the sample. The XRD and CSEM results for the Super Snapper salt sample (i.e., white solids) from Tank 5F (FTF-05-07-1) indicate the material contains hydrated sodium carbonate and bicarbonate salts along with some aluminum hydroxide. These compounds likely precipitated from the supernate in the tank. A solubility test showed the material

  18. ISOLOK VALVE ACCEPTANCE TESTING FOR DWPF SME SAMPLING PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, T.; Hera, K.; Coleman, C.; Jones, M.; Wiedenman, B.

    2011-12-05

    Evaluation of the Defense Waste Processing Facility (DWPF) Chemical Process Cell (CPC) cycle time identified several opportunities to improve the CPC processing time. Of the opportunities, a focus area related to optimizing the equipment and efficiency of the sample turnaround time for DWPF Analytical Laboratory was identified. The Mechanical Systems & Custom Equipment Development (MS&CED) Section of the Savannah River National Laboratory (SRNL) evaluated the possibility of using an Isolok{reg_sign} sampling valve as an alternative to the Hydragard{reg_sign} valve for taking process samples. Previous viability testing was conducted with favorable results using the Isolok sampler and reported in SRNL-STI-2010-00749 (1). This task has the potential to improve operability, reduce maintenance time and decrease CPC cycle time. This report summarizes the results from acceptance testing which was requested in Task Technical Request (TTR) HLW-DWPF-TTR-2010-0036 (2) and which was conducted as outlined in Task Technical and Quality Assurance Plan (TTQAP) SRNL-RP-2011-00145 (3). The Isolok to be tested is the same model which was tested, qualified, and installed in the Sludge Receipt Adjustment Tank (SRAT) sample system. RW-0333P QA requirements apply to this task. This task was to qualify the Isolok sampler for use in the DWPF Slurry Mix Evaporator (SME) sampling process. The Hydragard, which is the current baseline sampling method, was used for comparison to the Isolok sampling data. The Isolok sampler is an air powered grab sampler used to 'pull' a sample volume from a process line. The operation of the sampler is shown in Figure 1. The image on the left shows the Isolok's spool extended into the process line and the image on the right shows the sampler retracted and then dispensing the liquid into the sampling container. To determine tank homogeneity, a Coliwasa sampler was used to grab samples at a high and low location within the mixing tank. Data from

  19. Designing and testing the representative samplers for sampling a ...

    African Journals Online (AJOL)

    establishing the optimum mesh of grind for the various ores, to achieve effective separation of the cobalt minerals from those of copper. This prompted the designing and testing of representative samplers for sampling the milling circuit at Nkana Concentrator. In the design of the samplers, use was made of the Gy's formula to ...

  20. Profile Analysis of the Universal Nonverbal Intelligence Test Standardization Sample.

    Science.gov (United States)

    Wilhoit, Brian E.; McCallum, R. Steve

    2002-01-01

    A normative typology was developed and applied using multivariate profile analysis of subtest scores of the Universal Nonverbal Intelligence Test (UNIT) standardization sample. The results yielded a seven-profile cluster solution for the Extended Battery, and a six-profile cluster solution for the Standard Battery. Additionally, the results lend…

  1. A novel PMT test system based on waveform sampling

    Science.gov (United States)

    Yin, S.; Ma, L.; Ning, Z.; Qian, S.; Wang, Y.; Jiang, X.; Wang, Z.; Yu, B.; Gao, F.; Zhu, Y.; Wang, Z.

    2018-01-01

    Comparing with the traditional test system based on a QDC and TDC and scaler, a test system based on waveform sampling is constructed for signal sampling of the 8"R5912 and the 20"R12860 Hamamatsu PMT in different energy states from single to multiple photoelectrons. In order to achieve high throughput and to reduce the dead time in data processing, the data acquisition software based on LabVIEW is developed and runs with a parallel mechanism. The analysis algorithm is realized in LabVIEW and the spectra of charge, amplitude, signal width and rising time are analyzed offline. The results from Charge-to-Digital Converter, Time-to-Digital Converter and waveform sampling are discussed in detailed comparison.

  2. Testing exclusion restrictions and additive separability in sample selection models

    DEFF Research Database (Denmark)

    Huber, Martin; Mellace, Giovanni

    2014-01-01

    Standard sample selection models with non-randomly censored outcomes assume (i) an exclusion restriction (i.e., a variable affecting selection, but not the outcome) and (ii) additive separability of the errors in the selection process. This paper proposes tests for the joint satisfaction of these......Standard sample selection models with non-randomly censored outcomes assume (i) an exclusion restriction (i.e., a variable affecting selection, but not the outcome) and (ii) additive separability of the errors in the selection process. This paper proposes tests for the joint satisfaction...... of these assumptions by applying the approach of Huber and Mellace (Testing instrument validity for LATE identification based on inequality moment constraints, 2011) (for testing instrument validity under treatment endogeneity) to the sample selection framework. We show that the exclusion restriction and additive...... separability imply two testable inequality constraints that come from both point identifying and bounding the outcome distribution of the subpopulation that is always selected/observed. We apply the tests to two variables for which the exclusion restriction is frequently invoked in female wage regressions: non...

  3. Sample size in qualitative interview studies

    DEFF Research Database (Denmark)

    Malterud, Kirsti; Siersma, Volkert Dirk; Guassora, Ann Dorrit Kristiane

    2016-01-01

    Sample sizes must be ascertained in qualitative studies like in quantitative studies but not by the same means. The prevailing concept for sample size in qualitative studies is “saturation.” Saturation is closely tied to a specific methodology, and the term is inconsistently applied. We propose...... the concept “information power” to guide adequate sample size for qualitative studies. Information power indicates that the more information the sample holds, relevant for the actual study, the lower amount of participants is needed. We suggest that the size of a sample with sufficient information power...... depends on (a) the aim of the study, (b) sample specificity, (c) use of established theory, (d) quality of dialogue, and (e) analysis strategy. We present a model where these elements of information and their relevant dimensions are related to information power. Application of this model in the planning...

  4. GASOLINE VEHICLE EXHAUST PARTICLE SAMPLING STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Kittelson, D; Watts, W; Johnson, J; Zarling, D Schauer,J Kasper, K; Baltensperger, U; Burtscher, H

    2003-08-24

    The University of Minnesota collaborated with the Paul Scherrer Institute, the University of Wisconsin (UWI) and Ricardo, Inc to physically and chemically characterize the exhaust plume from recruited gasoline spark ignition (SI) vehicles. The project objectives were: (1) Measure representative particle size distributions from a set of on-road SI vehicles and compare these data to similar data collected on a small subset of light-duty gasoline vehicles tested on a chassis dynamometer with a dilution tunnel using the Unified Drive Cycle, at both room temperature (cold start) and 0 C (cold-cold start). (2) Compare data collected from SI vehicles to similar data collected from Diesel engines during the Coordinating Research Council E-43 project. (3) Characterize on-road aerosol during mixed midweek traffic and Sunday midday periods and determine fleet-specific emission rates. (4) Characterize bulk- and size-segregated chemical composition of the particulate matter (PM) emitted in the exhaust from the gasoline vehicles. Particle number concentrations and size distributions are strongly influenced by dilution and sampling conditions. Laboratory methods were evaluated to dilute SI exhaust in a way that would produce size distributions that were similar to those measured during laboratory experiments. Size fractionated samples were collected for chemical analysis using a nano-microorifice uniform deposit impactor (nano-MOUDI). In addition, bulk samples were collected and analyzed. A mixture of low, mid and high mileage vehicles were recruited for testing during the study. Under steady highway cruise conditions a significant particle signature above background was not measured, but during hard accelerations number size distributions for the test fleet were similar to modern heavy-duty Diesel vehicles. Number emissions were much higher at high speed and during cold-cold starts. Fuel specific number emissions range from 1012 to 3 x 1016 particles/kg fuel. A simple

  5. Robustness to non-normality of various tests for the one-sample location problem

    Directory of Open Access Journals (Sweden)

    Michelle K. McDougall

    2004-01-01

    Full Text Available This paper studies the effect of the normal distribution assumption on the power and size of the sign test, Wilcoxon's signed rank test and the t-test when used in one-sample location problems. Power functions for these tests under various skewness and kurtosis conditions are produced for several sample sizes from simulated data using the g-and-k distribution of MacGillivray and Cannon [5].

  6. Test Anxiety Prevalence and Gender Differences in a Sample of English Secondary School Students

    Science.gov (United States)

    Putwain, Dave; Daly, Anthony L.

    2014-01-01

    The aim of this study was to estimate the proportion of students who report themselves as highly test anxious in a sample of English secondary schools and whether this proportion differed by gender. Self-report test anxiety data were collected from 2435 secondary school students in 11 schools. Results showed that 16.4% of the sample reported…

  7. Development and Validation of an Admission Test Designed to Assess Samples of Performance on Academic Tasks

    Science.gov (United States)

    Tanilon, Jenny; Segers, Mien; Vedder, Paul; Tillema, Harm

    2009-01-01

    This study illustrates the development and validation of an admission test, labeled as Performance Samples on Academic Tasks in Educational Sciences (PSAT-Ed), designed to assess samples of performance on academic tasks characteristic of those that would eventually be encountered by examinees in an Educational Sciences program. The test was based…

  8. Sample Canister Capture Mechanism for Mars Sample Return: Functional and environmental test of the elegant breadboard model

    Science.gov (United States)

    Carta, R.; Filippetto, D.; Lavagna, M.; Mailland, F.; Falkner, P.; Larranaga, J.

    2015-12-01

    The paper provides recent updates about the ESA study: Sample Canister Capture Mechanism Design and Breadboard developed under the Mars Robotic Exploration Preparation (MREP) program. The study is part of a set of feasibility studies aimed at identifying, analysing and developing technology concepts enabling the future international Mars Sample Return (MSR) mission. The MSR is a challenging mission with the purpose of sending a Lander to Mars, acquire samples from its surface/subsurface and bring them back to Earth for further, more in depth, analyses. In particular, the technology object of the Study is relevant to the Capture Mechanism that, mounted on the Orbiter, is in charge of capturing and securing the Sample Canister, or Orbiting Sample, accommodating the Martian soil samples, previously delivered in Martian orbit by the Mars Ascent Vehicle. An elegant breadboard of such a device was implemented and qualified under an ESA contract primed by OHB-CGS S.p.A. and supported by Politecnico di Milano, Department of Aerospace Science and Technology: in particular, functional tests were conducted at PoliMi-DAST and thermal and mechanical test campaigns occurred at Serms s.r.l. facility. The effectiveness of the breadboard design was demonstrated and the obtained results, together with the design challenges, issues and adopted solutions are critically presented in the paper. The breadboard was also tested on a parabolic flight to raise its Technology Readiness Level to 6; the microgravity experiment design, adopted solutions and results are presented as well in the paper.

  9. How to prepare cytological samples for molecular testing.

    Science.gov (United States)

    Bellevicine, Claudio; Malapelle, Umberto; Vigliar, Elena; Pisapia, Pasquale; Vita, Giulia; Troncone, Giancarlo

    2017-10-01

    This review is focused on the challenges in standardising and optimising molecular testing workflow in cytopathology. Although cytological samples yield optimal quality DNA, whose minimal amounts in most cases suffice even for multigene mutational profiling, the success of molecular testing is strongly dependent on standardised preanalytical protocols for maximising DNA yield and quality. Sample cytopreparation influences, even more, the quality of RNA and consequently the potential success of reverse transcription-PCR. Here, the educational and technical involvement of the cytopathologist as a relevant component of a multidisciplinary team, in the issues related to test request, specimen collection, fixation, processing, staining, tumour fraction enrichment, DNA quality/quantity assessment and storage conditions is discussed. In addition, the specific sample requirements related to more recent technological developments are examined, underlining the modern role of the cytopathologist, whose continuous education is crucial to meet the opportunities of molecular medicine. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. Non-parametric sign test and paired samples test of effectiveness of official FX intervention

    Directory of Open Access Journals (Sweden)

    Marinković Srđan

    2014-01-01

    Full Text Available This article is an event study of the effectiveness of official foreign exchange interventions by the National Bank of Serbia (NBS in the RSD/EUR market. As the NBS does not have a formally modelled response function we assume that it intervenes as is expected according to its mandate, i.e., to prevent excess daily fluctuations. This paper tests two alternative goals of official intervention, marking as a success an event in which the NBS either breaks/reverses or smooths an ongoing exchange rate movement. According to a pre-defined time window for an intervention-clustering event, a nonparametric sign test supported the view that the NBS has failed to reverse the trend but is fairly effective in smoothing exchange rate return. However, even the smoothing effect is identified as short lasting. A paired samples test leads to similar findings, but because of weak support for the necessary conditions of sampling distribution it remains less conclusive. [Projekat Ministarstva nauke Republike Srbije, br. 179015: Challenges and prospects of structural changes in Serbia: Strategic directions for economic development and harmonization with EU requirements

  11. Performance of an adult Brazilian sample on the Trail Making Test and Stroop Test

    Directory of Open Access Journals (Sweden)

    Kenia Repiso Campanholo

    Full Text Available ABSTRACT Objective: The Trail Making Test (TMT and Stroop Test (ST are attention tests widely used in clinical practice and research. The aim of this study was to provide normative data for the adult Brazilian population and to study the influence of gender, age and education on the TMT parts A and B, and ST cards A, B and C. Methods: We recruited 1447 healthy subjects aged ≥18 years with an educational level of 0-25 years who were native speakers of Portuguese (Brazilian. The subjects were evaluated by the Matrix Reasoning and Vocabulary subtests of the Wechsler Adult Intelligence Scale-III, along with the TMTA, TMTB and ST A, B and C. Results: Among the participants, mean intellectual efficiency was 103.20 (SD: 12.0, age 41.0 (SD: 16.4 years and education 11.9 (SD: 5.6 years. There were significant differences between genders on the TMTA (p=0.002, TMTB (p=0.017 and STC (p=0.024. Age showed a positive correlation with all attention tests, whereas education showed a negative correlation. Gender was not found to be significant on the multiple linear regression model, but age and education maintained their interference. Conclusion: Gender did not have the major impact on attentional tasks observed for age and education, both of which should be considered in the stratification of normative samples.

  12. Enhanced Sampling and Analysis, Selection of Technology for Testing

    Energy Technology Data Exchange (ETDEWEB)

    Svoboda, John; Meikrantz, David

    2010-02-01

    The focus of this study includes the investigation of sampling technologies used in industry and their potential application to nuclear fuel processing. The goal is to identify innovative sampling methods using state of the art techniques that could evolve into the next generation sampling and analysis system for metallic elements. This report details the progress made in the first half of FY 2010 and includes a further consideration of the research focus and goals for this year. Our sampling options and focus for the next generation sampling method are presented along with the criteria used for choosing our path forward. We have decided to pursue the option of evaluating the feasibility of microcapillary based chips to remotely collect, transfer, track and supply microliters of sample solutions to analytical equipment in support of aqueous processes for used nuclear fuel cycles. Microchip vendors have been screened and a choice made for the development of a suitable microchip design followed by production of samples for evaluation by ANL, LANL, and INL on an independent basis.

  13. Right or wrong sample received for coagulation testing? Tentative algorithms for detection of an incorrect type of sample.

    Science.gov (United States)

    Lippi, G; Salvagno, G L; Adcock, D M; Gelati, M; Guidi, G C; Favaloro, E J

    2010-02-01

    Inappropriate blood collection potentially comprises the major pre-analytical problem for coagulation testing. Inappropriate samples are most difficult to detect when received as secondary aliquots, common for referred tests. This study aimed to identify a simple, quick and inexpensive process to help laboratories distinguish the type of sample, should there be suspicion of inappropriate collection. Samples from 15 patients [selected on the basis that four different primary tubes were available: serum, citrated plasma, ethylene diamine tetraacetic acid (EDTA) plasma, lithium-heparin plasma], were tested for common electrolytes that might substantially differ according to the type of sample. In citrated plasma, potassium, chloride, calcium and magnesium were significantly decreased compared with serum and lithium-heparin plasma, while sodium was markedly increased. In EDTA plasma, sodium and chloride were significantly decreased compared with both serum and lithium-heparin plasma, potassium was always >14 mmol/l, whereas magnesium and calcium were virtually undetectable. These data allowed development of two algorithms for differential identification of citrated plasma vs. other samples with 100% sensitivity and specificity, the former based on the sequential measurement of potassium, calcium and sodium, the latter on potassium and sodium. These simple assays can supplement classical coagulation test methods to identify most inappropriate blood collections and validate sample rejection.

  14. Impact of genetic counseling and Connexin-26 and Connexin-30 testing on deaf identity and comprehension of genetic test results in a sample of deaf adults: a prospective, longitudinal study

    National Research Council Canada - National Science Library

    Palmer, Christina G S; Boudreault, Patrick; Baldwin, Erin E; Sinsheimer, Janet S

    2014-01-01

    .... Questionnaire data collected from 209 deaf adults at four time points (baseline, immediately following pre-test genetic counseling, 1-month following genetic test result disclosure, and 6-months after result disclosure) were analyzed...

  15. Electromagnetic Compatibility Testing Studies

    Science.gov (United States)

    Trost, Thomas F.; Mitra, Atindra K.

    1996-01-01

    This report discusses the results on analytical models and measurement and simulation of statistical properties from a study of microwave reverberation (mode-stirred) chambers performed at Texas Tech University. Two analytical models of power transfer vs. frequency in a chamber, one for antenna-to-antenna transfer and the other for antenna to D-dot sensor, were experimentally validated in our chamber. Two examples are presented of the measurement and calculation of chamber Q, one for each of the models. Measurements of EM power density validate a theoretical probability distribution on and away from the chamber walls and also yield a distribution with larger standard deviation at frequencies below the range of validity of the theory. Measurements of EM power density at pairs of points which validate a theoretical spatial correlation function on the chamber walls and also yield a correlation function with larger correlation length, R(sub corr), at frequencies below the range of validity of the theory. A numerical simulation, employing a rectangular cavity with a moving wall shows agreement with the measurements. The determination that the lowest frequency at which the theoretical spatial correlation function is valid in our chamber is considerably higher than the lowest frequency recommended by current guidelines for utilizing reverberation chambers in EMC testing. Two suggestions have been made for future studies related to EMC testing.

  16. Factor Structure of the Revised TOEIC[R] Test: A Multiple-Sample Analysis

    Science.gov (United States)

    In'nami, Yo; Koizumi, Rie

    2012-01-01

    This study examined the factor structure of the listening and reading sections of the revised Test of English for International Communication (TOEIC[R]) test. The data from the TOEIC IP (institutional program) test taken by 569 English learners were randomly split into two samples (n = 285 vs. 284). Four models (higher-order, correlated,…

  17. Cervical cancer screening in rural Bhutan with the careHPV test on self-collected samples: an ongoing cross-sectional, population-based study (REACH-Bhutan).

    Science.gov (United States)

    Baussano, Iacopo; Tshering, Sangay; Choden, Tashi; Lazzarato, Fulvio; Tenet, Vanessa; Plummer, Martyn; Franceschi, Silvia; Clifford, Gary M; Tshomo, Ugyen

    2017-07-19

    The Bhutanese Screening Programme recommends a Pap smear every 3 years for women aged 25-65 years, and coverage ranges from 20% to 60%, being especially challenging in rural settings. The 'REACH-Bhutan' study was conducted to assess the feasibility and outcomes of a novel approach to cervical cancer screening in rural Bhutan. Cross-sectional, population-based study of cervical cancer screening based on the careHPV test on self-collected samples. Women were recruited in rural primary healthcare centres, that is, Basic Health Units (BHU), across Bhutan. Overall, 3648 women aged 30-60 were invited from 15 BHUs differing in accessibility, size and ethnic composition of the population. Participants provided a self-collected cervicovaginal sample and were interviewed. Samples were tested using careHPV in Thimphu (the Bhutanese capital) referral laboratory. Screening participation by geographic area, centre, age and travelling time. Previous screening history and careHPV positivity by selected characteristics of the participants. In April/May 2016, 2590 women (median age: 41) were enrolled. Study participation was 71% and significantly heterogeneous by BHU (range: 31%-96%). Participation decreased with increase in age (81% in women aged 30-39 years; 59% in ≥50 years) and travelling time (90% in women living 6 hours away). 50% of participants reported no previous screening, with the proportion of never-screened women varying significantly by BHU (range: 2%-72%). 265 women (10%; 95% CI 9% to 11%) were careHPV positive, with a significant variation by BHU (range: 5%-19%) and number of sexual partners (prevalence ratio for ≥3 vs 0-1, 1.55; 95% CI 1.05 to 2.27). Community-based cervical cancer screening by testing self-collected samples for human papillomavirus (HPV) can achieve high coverage in rural Bhutan. However, solutions to bring self-collection, HPV testing and precancer treatment closer to the remotest villages are needed. © Article author(s) (or

  18. 21 CFR 864.3260 - OTC test sample collection systems for drugs of abuse testing.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false OTC test sample collection systems for drugs of abuse testing. 864.3260 Section 864.3260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Pathology...

  19. Sample size computation for association studies using case–parents ...

    Indian Academy of Sciences (India)

    sample size for case–control association studies is discussed. Materials and methods. Parameter settings. We consider a candidate locus with two alleles A and a where. A is putatively associated with the disease status (increasing. Keywords. sample size; association tests; genotype relative risk; power; autism. Journal of ...

  20. Effects of post-sampling analysis time, type of blood samples and collection tubes on values of blood gas testing.

    Science.gov (United States)

    Smajić, Jasmina; Kadić, Damira; Hasić, Sabaheta; Serdarević, Nafija

    2015-08-01

    To investigate effects of post-sampling analysis time, a type of blood samples and collection tubes on blood gas testing. This study included 100 patients at the Clinic for Pulmonary Diseases, Clinical Centre Sarajevo. The partial pressure of oxygen (pO2) and carbon dioxide (pCO2), and the oxygen saturation level of hemoglobin (sO2) were analyzed in the arterial blood samples (ABS) and capillary blood samples (CBS) by a potentiometric method using a blood gas analyzer ABL 555 (Radiometer, Copenhagen, Denmark). Paired measurements of ABS were performed within 15 minutes and after 60 minutes from sampling and compared. The results of CBS obtained within 15 minutes were compared with matching ABS results, as well as the results obtained from CBS within 15 minutes taken into glass and plastic tubes. pO2 and sO2 values were significantly lower after 60 minutes compared to those within 15 minutes in ABS (9.20±1.89 vs. 9.51±1.95 and 91.25±5.03 vs. 92.40±4.5; pblood values were not influenced significantly (p>0.05). The length of post-sampling analysis time, a type of blood samples and collection tubes have significant impact on blood oxygen parameters. Analysis within 15 minutes after blood sampling is considered as appropriate. Copyright© by the Medical Assotiation of Zenica-Doboj Canton.

  1. Sample Size and Statistical Power Calculation in Genetic Association Studies

    Directory of Open Access Journals (Sweden)

    Eun Pyo Hong

    2012-06-01

    Full Text Available A sample size with sufficient statistical power is critical to the success of genetic association studies to detect causal genes of human complex diseases. Genome-wide association studies require much larger sample sizes to achieve an adequate statistical power. We estimated the statistical power with increasing numbers of markers analyzed and compared the sample sizes that were required in case-control studies and case-parent studies. We computed the effective sample size and statistical power using Genetic Power Calculator. An analysis using a larger number of markers requires a larger sample size. Testing a single-nucleotide polymorphism (SNP marker requires 248 cases, while testing 500,000 SNPs and 1 million markers requires 1,206 cases and 1,255 cases, respectively, under the assumption of an odds ratio of 2, 5% disease prevalence, 5% minor allele frequency, complete linkage disequilibrium (LD, 1:1 case/control ratio, and a 5% error rate in an allelic test. Under a dominant model, a smaller sample size is required to achieve 80% power than other genetic models. We found that a much lower sample size was required with a strong effect size, common SNP, and increased LD. In addition, studying a common disease in a case-control study of a 1:4 case-control ratio is one way to achieve higher statistical power. We also found that case-parent studies require more samples than case-control studies. Although we have not covered all plausible cases in study design, the estimates of sample size and statistical power computed under various assumptions in this study may be useful to determine the sample size in designing a population-based genetic association study.

  2. Synthesizing Information From Language Samples and Standardized Tests in School-Age Bilingual Assessment

    Science.gov (United States)

    Pham, Giang

    2017-01-01

    Purpose Although language samples and standardized tests are regularly used in assessment, few studies provide clinical guidance on how to synthesize information from these testing tools. This study extends previous work on the relations between tests and language samples to a new population—school-age bilingual speakers with primary language impairment—and considers the clinical implications for bilingual assessment. Method Fifty-one bilingual children with primary language impairment completed narrative language samples and standardized language tests in English and Spanish. Children were separated into younger (ages 5;6 [years;months]–8;11) and older (ages 9;0–11;2) groups. Analysis included correlations with age and partial correlations between language sample measures and test scores in each language. Results Within the younger group, positive correlations with large effect sizes indicated convergence between test scores and microstructural language sample measures in both Spanish and English. There were minimal correlations in the older group for either language. Age related to English but not Spanish measures. Conclusions Tests and language samples complement each other in assessment. Wordless picture-book narratives may be more appropriate for ages 5–8 than for older children. We discuss clinical implications, including a case example of a bilingual child with primary language impairment, to illustrate how to synthesize information from these tools in assessment. PMID:28055056

  3. Synthesizing Information From Language Samples and Standardized Tests in School-Age Bilingual Assessment.

    Science.gov (United States)

    Ebert, Kerry Danahy; Pham, Giang

    2017-01-01

    Although language samples and standardized tests are regularly used in assessment, few studies provide clinical guidance on how to synthesize information from these testing tools. This study extends previous work on the relations between tests and language samples to a new population-school-age bilingual speakers with primary language impairment-and considers the clinical implications for bilingual assessment. Fifty-one bilingual children with primary language impairment completed narrative language samples and standardized language tests in English and Spanish. Children were separated into younger (ages 5;6 [years;months]-8;11) and older (ages 9;0-11;2) groups. Analysis included correlations with age and partial correlations between language sample measures and test scores in each language. Within the younger group, positive correlations with large effect sizes indicated convergence between test scores and microstructural language sample measures in both Spanish and English. There were minimal correlations in the older group for either language. Age related to English but not Spanish measures. Tests and language samples complement each other in assessment. Wordless picture-book narratives may be more appropriate for ages 5-8 than for older children. We discuss clinical implications, including a case example of a bilingual child with primary language impairment, to illustrate how to synthesize information from these tools in assessment.

  4. Identification of Statistically Homogeneous Pixels Based on One-Sample Test

    Directory of Open Access Journals (Sweden)

    Keng-Fan Lin

    2017-01-01

    Full Text Available Statistically homogeneous pixels (SHP play a crucial role in synthetic aperture radar (SAR analysis. In past studies, various two-sample tests were applied on multitemporal SAR data stacks under the assumption of having stationary backscattering properties over time. In this letter, we propose the Robust T-test (TR to improve the effectiveness of test operation. The TR test reduces the impact of temporal variabilities and outliers, thus helping to identify SHP with assurances of similar temporal behaviors. This method includes three steps: (1 signal suppression; (2 outlier removal; and (3 one-sample test. In the experiments, we apply the TR test on both simulated and real data. Different stack sizes, types of distributions, and hypothesis tests are compared. Results of both experiments signify that the TR test outperforms conventional approaches and provides reliable SHP for SAR image analysis.

  5. Helicobacter pylori: Interrelationship between the urea test in dental plaque samples and gastric biopsy

    OpenAIRE

    De la Cruz Valle, Daniel; Cirujano Dentista, Práctica privada. Egresado de la Universidad Nacional Mayor de San Marcos.; Moromi Nakata, Hilda; Profesor principal del Departamento de Ciencias Básicas de la Facultad de Odontología de la Universidad Nacional Mayor de San Marcos.

    2014-01-01

    With the purpose of establishing interrelationship between the urea test in dental plaque and gastric biopsy samples to determine the presence of Helicobacter pylori, this study was performed in 50 patients from the National Police Central Hospital. Simultaneously, samples from the dental plaque and gastric biopsies were taken from patients of the Gastroenterology Department, the same that were submitted to endoscopies by their medical attendant. Samples of their stomachs were obtained by a p...

  6. Phootprint - A Phobos sample return mission study

    Science.gov (United States)

    Koschny, Detlef; Svedhem, Håkan; Rebuffat, Denis

    Introduction ESA is currently studying a mission to return a sample from Phobos, called Phootprint. This study is performed as part of ESA’s Mars Robotic Exploration Programme. Part of the mission goal is to prepare technology needed for a sample return mission from Mars itself; the mission should also have a strong scientific justification, which is described here. 1. Science goal The main science goal of this mission will be to Understand the formation of the Martian moons Phobos and put constraints on the evolution of the solar system. Currently, there are several possibilities for explaining the formation of the Martian moons: (a) co-formation with Mars (b) capture of objects coming close to Mars (c) Impact of a large body onto Mars and formation from the impact ejecta The main science goal of this mission is to find out which of the three scenarios is the most probable one. To do this, samples from Phobos would be returned to Earth and analyzed with extremely high precision in ground-based laboratories. An on-board payload is foreseen to provide information to put the sample into the necessary geological context. 2. Mission Spacecraft and payload will be based on experience gained from previous studies to Martian moons and asteroids. In particular the Marco Polo and MarcoPolo-R asteroid sample return mission studies performed at ESA were used as a starting point. Currently, industrial studies are ongoing. The initial starting assumption was to use a Soyuz launcher. Uunlike the initial Marco Polo and MarcoPolo-R studies to an asteroid, a transfer stage will be needed. Another main difference to an asteroid mission is the fact that the spacecraft actually orbits Mars, not Phobos or Deimos. It is possible to select a spacecraft orbit, which in a Phobos- or Deimos-centred reference system would give an ellipse around the moon. The following model payload is currently foreseen: - Wide Angle Camera, - Narrow Angle Camera, - Close-Up Camera, - Context camera for

  7. On Wasserstein Two-Sample Testing and Related Families of Nonparametric Tests

    Directory of Open Access Journals (Sweden)

    Aaditya Ramdas

    2017-01-01

    Full Text Available Nonparametric two-sample or homogeneity testing is a decision theoretic problem that involves identifying differences between two random variables without making parametric assumptions about their underlying distributions. The literature is old and rich, with a wide variety of statistics having being designed and analyzed, both for the unidimensional and the multivariate setting. Inthisshortsurvey,wefocusonteststatisticsthatinvolvetheWassersteindistance. Usingan entropic smoothing of the Wasserstein distance, we connect these to very different tests including multivariate methods involving energy statistics and kernel based maximum mean discrepancy and univariate methods like the Kolmogorov–Smirnov test, probability or quantile (PP/QQ plots and receiver operating characteristic or ordinal dominance (ROC/ODC curves. Some observations are implicit in the literature, while others seem to have not been noticed thus far. Given nonparametric two-sample testing’s classical and continued importance, we aim to provide useful connections for theorists and practitioners familiar with one subset of methods but not others.

  8. The validation of a computer-adaptive test (CAT) for assessing health-related quality of life in children and adolescents in a clinical sample: study design, methods and first results of the Kids-CAT study.

    Science.gov (United States)

    Barthel, D; Otto, C; Nolte, S; Meyrose, A-K; Fischer, F; Devine, J; Walter, O; Mierke, A; Fischer, K I; Thyen, U; Klein, M; Ankermann, T; Rose, M; Ravens-Sieberer, U

    2017-05-01

    Recently, we developed a computer-adaptive test (CAT) for assessing health-related quality of life (HRQoL) in children and adolescents: the Kids-CAT. It measures five generic HRQoL dimensions. The aims of this article were (1) to present the study design and (2) to investigate its psychometric properties in a clinical setting. The Kids-CAT study is a longitudinal prospective study with eight measurements over one year at two University Medical Centers in Germany. For validating the Kids-CAT, 270 consecutive 7- to 17-year-old patients with asthma (n = 52), diabetes (n = 182) or juvenile arthritis (n = 36) answered well-established HRQoL instruments (Pediatric Quality of Life Inventory™ (PedsQL), KIDSCREEN-27) and scales measuring related constructs (e.g., social support, self-efficacy). Measurement precision, test-retest reliability, convergent and discriminant validity were investigated. The mean standard error of measurement ranged between .38 and .49 for the five dimensions, which equals a reliability between .86 and .76, respectively. The Kids-CAT measured most reliably in the lower HRQoL range. Convergent validity was supported by moderate to high correlations of the Kids-CAT dimensions with corresponding PedsQL dimensions ranging between .52 and .72. A lower correlation was found between the social dimensions of both instruments. Discriminant validity was confirmed by lower correlations with non-corresponding subscales of the PedsQL. The Kids-CAT measures pediatric HRQoL reliably, particularly in lower areas of HRQoL. Its test-retest reliability should be re-investigated in future studies. The validity of the instrument was demonstrated. Overall, results suggest that the Kids-CAT is a promising candidate for detecting psychosocial needs in chronically ill children.

  9. A Hardy-Weinberg equilibrium test for analyzing population genetic surveys with complex sample designs.

    Science.gov (United States)

    Moonesinghe, Ramal; Yesupriya, Ajay; Chang, Man-Huei; Dowling, Nicole F; Khoury, Muin J; Scott, Alastair J

    2010-04-15

    Testing for deviations from Hardy-Weinberg equilibrium is a widely recommended practice for population-based genetic association studies. However, current methods for this test assume a simple random sample and may not be appropriate for sample surveys with complex survey designs. In this paper, the authors present a test for Hardy-Weinberg equilibrium that adjusts for the sample weights and correlation of data collected in complex surveys. The authors perform this test by using a simple adjustment to procedures developed to analyze data from complex survey designs available within the SAS statistical software package (SAS Institute, Inc., Cary, North Carolina). Using 90 genetic markers from the Third National Health and Nutrition Examination Survey, the authors found that survey-adjusted and -unadjusted estimates of the disequilibrium coefficient were generally similar within self-reported races/ethnicities. However, estimates of the variance of the disequilibrium coefficient were significantly different between the 2 methods. Because the results of the survey-adjusted tests account for correlation among participants sampled within the same cluster, and the possibility of having related individuals sampled from the same household, the authors recommend use of this test when analyzing genetic data originating from sample surveys with complex survey designs to assess deviations from Hardy-Weinberg equilibrium.

  10. Pigeons exhibit higher accuracy for chosen memory tests than for forced memory tests in duration matching-to-sample.

    Science.gov (United States)

    Adams, Allison; Santi, Angelo

    2011-03-01

    Following training to match 2- and 8-sec durations of feederlight to red and green comparisons with a 0-sec baseline delay, pigeons were allowed to choose to take a memory test or to escape the memory test. The effects of sample omission, increases in retention interval, and variation in trial spacing on selection of the escape option and accuracy were studied. During initial testing, escaping the test did not increase as the task became more difficult, and there was no difference in accuracy between chosen and forced memory tests. However, with extended training, accuracy for chosen tests was significantly greater than for forced tests. In addition, two pigeons exhibited higher accuracy on chosen tests than on forced tests at the short retention interval and greater escape rates at the long retention interval. These results have not been obtained in previous studies with pigeons when the choice to take the test or to escape the test is given before test stimuli are presented. It appears that task-specific methodological factors may determine whether a particular species will exhibit the two behavioral effects that were initially proposed as potentially indicative of metacognition.

  11. Active versus Passive Sample Attrition: The Health and Retirement Study

    OpenAIRE

    Honggao Cao; Daniel H. Hill

    2005-01-01

    This paper investigates sample attrition in the Health and Retirement Study (HRS). We compare attrition behavior in two of the HRS cohorts: original HRS cohort and AHEAD cohort. We distinguish attrition due to death (passive attrition) from attrition due to other causes (active attrition), examining potential effects of different attrition modes on the representativeness of the remaining samples. This distinction is justified based on a specification test on a multinomial logistic regression ...

  12. Testing Hardy-Weinberg equilibrium using mother-child case-control samples.

    Science.gov (United States)

    Chen, Jinbo; Zheng, Haitao; Wilson, Melissa L; Kraft, Peter

    2009-09-01

    Genetic association studies of obstetric complications may genotype case and control mothers, or their respective newborns, or both case-control mothers and their children. The relatively high prevalence of many obstetric complications and the availability of both maternal and offspring's genotype data have provided motivation to study new methods for testing for deviations from Hardy-Weinberg equilibrium (HWE). We propose four novel test statistics, each of which uses a different type of data as follows: (1) a test using maternal case-control genotype data, (2) a test using offspring genotype data, (3) a combination of the first and second tests, and (4) a test based on the joint classification of case-control maternal-child genotype data. The selection of case and control mothers (and thus their children) is accounted for by weighting both maternal and child contributions to the test statistics with sampling probabilities. Our tests thus do not require that the phenotype be rare as is the case for HWE tests using only controls, and are particularly suitable for genetic association studies of relatively common complications such as premature birth. The third and fourth tests described above utilize both maternal and child genotype data and appropriately account for the correlation between maternal and child genotypes. On the basis of extensive simulation studies to compare the type-I error and power for proposed tests, we recommend the third combined test statistic for routine use in the analysis of case-control studies of mother-child pairs.

  13. The Childhood Asperger Syndrome Test (CAST): Test-Retest Reliability in a High Scoring Sample

    Science.gov (United States)

    Allison, Carrie; Williams, Jo; Scott, Fiona; Stott, Carol; Bolton, Patrick; Baron-Cohen, Simon; Brayne, Carol

    2007-01-01

    The Childhood Asperger Syndrome Test (CAST) is a 37-item parental self-completion questionnaire designed to screen for high-functioning autism spectrum conditions in epidemiological research. The CAST has previously demonstrated good accuracy for use as a screening test, with high sensitivity in studies with primary school aged children in…

  14. Dairy cows with metritis: Coxiella burnetii test results in uterine, blood and bulk milk samples.

    Science.gov (United States)

    Muskens, J; van Maanen, C; Mars, M H

    2011-01-10

    In cattle, Coxiella burnetii infections are generally asymptomatic but can also be associated with reproductive disorders. Metritis is considered as one of the symptoms of C. burnetii infections, but reliable information is lacking. Therefore, information on the presence of C. burnetii in the uterine content of cows with metritis is important to increase our knowledge on this pathogen. In this study, the uterine content of 45 dairy cows with metritis belonging to 12 herds was tested for C. burnetii with a real-time PCR assay. Only one uterine sample tested PCR (highly) positive, all other samples were PCR negative. The PCR positive cow tested also positive for antibodies. Three other cows from other herds tested antibody positive. The bulk milk (BM) samples of these 12 herds were tested by real-time PCR assay and antibody-ELISA. Six BM samples (50%) were positive in PCR and 10 (83%) were positive in ELISA. Culturing the uterus samples by bacteriology, the most frequently cultured bacteria were arcanobacterium (n=24), E. coli (n=16), other streptococci (n=10), Streptococcus uberis (n=8) and Streptococcus dysgalactiae (n=5). This study indicates that C. burnetii is not an important cause for metritis in dairy herds, although apparently C. burnetii was or had been present in most of these herds. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. Cost-effectiveness of one versus two sample faecal immunochemical testing for colorectal cancer screening.

    Science.gov (United States)

    Goede, S Lucas; van Roon, Aafke H C; Reijerink, Jacqueline C I Y; van Vuuren, Anneke J; Lansdorp-Vogelaar, Iris; Habbema, J Dik F; Kuipers, Ernst J; van Leerdam, Monique E; van Ballegooijen, Marjolein

    2013-05-01

    The sensitivity and specificity of a single faecal immunochemical test (FIT) are limited. The performance of FIT screening can be improved by increasing the screening frequency or by providing more than one sample in each screening round. This study aimed to evaluate if two-sample FIT screening is cost-effective compared with one-sample FIT. The MISCAN-colon microsimulation model was used to estimate costs and benefits of strategies with either one or two-sample FIT screening. The FIT cut-off level varied between 50 and 200 ng haemoglobin/ml, and the screening schedule was varied with respect to age range and interval. In addition, different definitions for positivity of the two-sample FIT were considered: at least one positive sample, two positive samples, or the mean of both samples being positive. Within an exemplary screening strategy, biennial FIT from the age of 55-75 years, one-sample FIT provided 76.0-97.0 life-years gained (LYG) per 1000 individuals, at a cost of € 259,000-264,000 (range reflects different FIT cut-off levels). Two-sample FIT screening with at least one sample being positive provided 7.3-12.4 additional LYG compared with one-sample FIT at an extra cost of € 50,000-59,000. However, when all screening intervals and age ranges were considered, intensifying screening with one-sample FIT provided equal or more LYG at lower costs compared with two-sample FIT. If attendance to screening does not differ between strategies it is recommended to increase the number of screening rounds with one-sample FIT screening, before considering increasing the number of FIT samples provided per screening round.

  16. Sample Size for the "Z" Test and Its Confidence Interval

    Science.gov (United States)

    Liu, Xiaofeng Steven

    2012-01-01

    The statistical power of a significance test is closely related to the length of the confidence interval (i.e. estimate precision). In the case of a "Z" test, the length of the confidence interval can be expressed as a function of the statistical power. (Contains 1 figure and 1 table.)

  17. Statistics of sampling for microbiological testing of foodborne pathogens

    Science.gov (United States)

    Despite the many recent advances in protocols for testing for pathogens in foods, a number of challenges still exist. For example, the microbiological safety of food cannot be completely ensured by testing because microorganisms are not evenly distributed throughout the food. Therefore, since it i...

  18. Acceptability of routine HIV counselling and testing among a sample ...

    African Journals Online (AJOL)

    Routine HIV counseling and testing (RCT) is a necessary first step in accessing health care for persons who may test HIV-positive. Despite the availability of RCT in many South African settings, uptake has often been low. We sought to determine whether the main components of the Health Belief Model (HBM), namely ...

  19. Method and apparatus for processing a test sample to concentrate an analyte in the sample from a solvent in the sample

    Science.gov (United States)

    Turner, Terry D.; Beller, Laurence S.; Clark, Michael L.; Klingler, Kerry M.

    1997-01-01

    A method of processing a test sample to concentrate an analyte in the sample from a solvent in the sample includes: a) boiling the test sample containing the analyte and solvent in a boiling chamber to a temperature greater than or equal to the solvent boiling temperature and less than the analyte boiling temperature to form a rising sample vapor mixture; b) passing the sample vapor mixture from the boiling chamber to an elongated primary separation tube, the separation tube having internal sidewalls and a longitudinal axis, the longitudinal axis being angled between vertical and horizontal and thus having an upper region and a lower region; c) collecting the physically transported liquid analyte on the internal sidewalls of the separation tube; and d) flowing the collected analyte along the angled internal sidewalls of the separation tube to and pass the separation tube lower region. The invention also includes passing a turbulence inducing wave through a vapor mixture to separate physically transported liquid second material from vaporized first material. Apparatus are also disclosed for effecting separations. Further disclosed is a fluidically powered liquid test sample withdrawal apparatus for withdrawing a liquid test sample from a test sample container and for cleaning the test sample container.

  20. The Agreement between the MMSE and IQCODE Tests in a Community-Based Sample of Subjects Aged 70 Years or Older Receiving In-Home Nursing: An Explorative Study

    Directory of Open Access Journals (Sweden)

    Øyvind Kirkevold

    2015-02-01

    Full Text Available Aim: It was the aim of this study to compare the Mini-Mental State Examination (MMSE with the Informant Questionnaire for Cognitive Decline in the Elderly (IQCODE and to explore the characteristics of subjects with possible dementia with only one of the two tools. Methods: We used a random sample of patients aged 70+ receiving social service or in-home nursing. The patients were tested with the MMSE, and the next of kin was interviewed using the following: the IQCODE, the Cornell Scale for Depression in Dementia (CSDD, the Neuropsychiatric Inventory (NPI, instrumental activities of daily living (IADL, personal ADL (PADL and the General Medical Health Rating (GMHR. Results: Subjects with dementia defined only according to the MMSE showed a pattern of scores on IADL, PADL, CSDD, NPI-10 and GMHR similar to the no-dementia group according to both the MMSE and the IQCODE. Those with dementia defined only according to the IQCODE showed a pattern of scores similar to the possible dementia group according to both the MMSE and the IQCODE.

  1. Report on Electrochemcial Corrosion Testing of 241-SY-102 Grab Samples from the 2012 Grab Sampling Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Wyrwas, Richard B.; Lamothe, Margaret E.

    2013-05-30

    This report describes the results of the electrochemical testing performed on tank 241-SY-102 (SY-102) grab samples that were collected in support of corrosion mitigation. The objective of the work presented here was to determine corrosion resistance of tank SY-102 to the grab samples collected using electrochemical methods up to 50°C as well as to satisfy data quality objectives. Grab samples were collected at multiple elevations from Riser 003. The electrochemical corrosion testing was planned to consist of linear polarization resistance testing (LPR) and cyclic potentiodynamic polarization (CPP) testing at 50°C. The temperature would be lowered to 40 °C and the test repeated if the CPP curve indicated pitting corrosion at 50°C. Ifno pitting was indicated by the CPP curve, then a duplicate scan would be repeated at 50°C to confirm the first result. The testing would be complete if the duplicate CPP scan was consistent with the first. This report contains the CPP results of the testing of grab sample 2SY-12-03 and 2SY-12-03DUP composite sample tested under these conditions. There was no indication of pitting at 50°C, and the duplicate scan was in agreement with the first scan. Since no further testing was required, a third scan with a shorter rest time was performed and is present in this report.

  2. Reveal Salmonella 2.0 test for detection of Salmonella spp. in foods and environmental samples. Performance Tested Method 960801.

    Science.gov (United States)

    Hoerner, Rebecca; Feldpausch, Jill; Gray, R Lucas; Curry, Stephanie; Islam, Zahidul; Goldy, Tim; Klein, Frank; Tadese, Theodros; Rice, Jennifer; Mozola, Mark

    2011-01-01

    Reveal Salmonella 2.0 is an improved version of the original Reveal Salmonella lateral flow immunoassay and is applicable to the detection of Salmonella enterica serogroups A-E in a variety of food and environmental samples. A Performance Tested Method validation study was conducted to compare performance of the Reveal 2.0 method with that of the U.S. Department of Agriculture-Food Safety and Inspection Service or U.S. Food and Drug Administration/Bacteriological Analytical Manual reference culture methods for detection of Salmonella spp. in chicken carcass rinse, raw ground turkey, raw ground beef, hot dogs, raw shrimp, a ready-to-eat meal product, dry pet food, ice cream, spinach, cantaloupe, peanut butter, stainless steel surface, and sprout irrigation water. In a total of 17 trials performed internally and four trials performed in an independent laboratory, there were no statistically significant differences in performance of the Reveal 2.0 and reference culture procedures as determined by Chi-square analysis, with the exception of one trial with stainless steel surface and one trial with sprout irrigation water where there were significantly more positive results by the Reveal 2.0 method. Considering all data generated in testing food samples using enrichment procedures specifically designed for the Reveal method, overall sensitivity of the Reveal method relative to the reference culture methods was 99%. In testing environmental samples, sensitivity of the Reveal method relative to the reference culture method was 164%. For select foods, use of the Reveal test in conjunction with reference method enrichment resulted in overall sensitivity of 92%. There were no unconfirmed positive results on uninoculated control samples in any trials for specificity of 100%. In inclusivity testing, 102 different Salmonella serovars belonging to serogroups A-E were tested and 99 were consistently positive in the Reveal test. In exclusivity testing of 33 strains of non

  3. Work sample tests voor selectie en matching in het hoger onderwijs

    NARCIS (Netherlands)

    Niessen, A. Susan M.; Meijer, Rob R.

    Het doel van selectie en matching in het Nederlandse hoger onderwijs is om de match tussen de student en de studie te vergroten. Veel traditionele methoden voor selectie en matching zijn hier minder geschikt voor. Onderzocht is of work sample tests, afkomstig uit de arbeids- en

  4. Theory testing using case studies

    DEFF Research Database (Denmark)

    Dissing Sørensen, Pernille; Løkke Nielsen, Ann-Kristina

    Case studies may have different research goals. One such goal is the testing of small-scale and middle-range theories. Theory testing refers to the critical examination, observation, and evaluation of the 'why' and 'how' of a specified phenomenon in a particular setting. In this paper, we focus...... on the strengths of theory-testing case studies. We specify research paths associated with theory testing in case studies and present a coherent argument for the logic of theoretical development and refinement using case studies. We emphasize different uses of rival explanations and their implications for research...... design. Finally, we discuss the epistemological logic, i.e., the value to larger research programmes, of such studies and, following Lakatos, conclude that the value of theory-testing case studies lies beyond naïve falsification and in their contribution to developing research programmes in a progressive...

  5. Aggregate impact testing of selected granite samples from sites in ...

    African Journals Online (AJOL)

    The Aggregate Impact Testing machine was used to measure the resistance to fa ilure of Rocks from five (5) selected granite quarries to a suddenly applied force using S ingapore standard. The results obtained show that brittleness (S20) value of the rocks were between 2 - 10. These values are less than the stated ...

  6. Hypothesis testing in genetic linkage analysis via Gibbs sampling ...

    African Journals Online (AJOL)

    Genetic linkage analysis involves estimating parameters in a genetic model in which a genetic trait is regressed on some factors such as polygenic values and environmental effects. Since only phenotypes are observed, hypothesis testing in such cases needs calculation of likelihood function in which one needs to consider ...

  7. Metacognitive Strategies and Test Performance: An Experience Sampling Analysis of Students' Learning Behavior

    Directory of Open Access Journals (Sweden)

    Ulrike E. Nett

    2012-01-01

    Full Text Available The aim of the present study was to explore students’ learning-related cognitions prior to an in-class achievement test, with a focus on metacognitive strategy use. A sample of 70 students in grade 11 (58.6% female, Mage=17.09 years completed a series of structured, state-based measures over a two-week period via the experience sampling method until the day before a class test. Results illustrated students’ self-regulatory ability to preserve their motivational and cognitive resources, with test-related cognitions evidenced significantly more often in learning-related as opposed leisure settings. Metacognitive strategy use was also found to significantly increase as the test date approached underscoring the goal-oriented nature of situated learning behaviors. Higher intercepts and increases in frequency of test-related cognitions over time positively corresponded to test performance. Of the three metacognitive strategies assessed, monitoring was found to positively correspond with test performance. Implications for future practice as well as implications for future research employing the experience sampling method are discussed.

  8. 40 CFR 53.57 - Test for filter temperature control during sampling and post-sampling periods.

    Science.gov (United States)

    2010-07-01

    ... are to be recorded with an analog recording device, the accuracy of the entire instrument-recorder... Class I and Class II Equivalent Methods for PM2.5 or PM10â2.5 § 53.57 Test for filter temperature... sampling is the ability of a sampler to maintain the temperature of the particulate matter sample filter...

  9. Ballistic penetration test results for Ductal and ultra-high performance concrete samples.

    Energy Technology Data Exchange (ETDEWEB)

    Reinhart, William Dodd; Thornhill, Tom Finley, III (KTech)

    2010-03-01

    This document provides detailed test results of ballistic impact experiments performed on several types of high performance concrete. These tests were performed at the Sandia National Laboratories Shock Thermodynamic Applied Research Facility using a 50 caliber powder gun to study penetration resistance of concrete samples. This document provides test results for ballistic impact experiments performed on two types of concrete samples, (1) Ductal{reg_sign} concrete is a fiber reinforced high performance concrete patented by Lafarge Group and (2) ultra-high performance concrete (UHPC) produced in-house by DoD. These tests were performed as part of a research demonstration project overseen by USACE and ERDC, at the Sandia National Laboratories Shock Thermodynamic Applied Research (STAR) facility. Ballistic penetration tests were performed on a single stage research powder gun of 50 caliber bore using a full metal jacket M33 ball projectile with a nominal velocity of 914 m/s (3000 ft/s). Testing was observed by Beverly DiPaolo from ERDC-GSL. In all, 31 tests were performed to achieve the test objectives which were: (1) recovery of concrete test specimens for post mortem analysis and characterization at outside labs, (2) measurement of projectile impact velocity and post-penetration residual velocity from electronic and radiographic techniques and, (3) high-speed photography of the projectile prior to impact, impact and exit of the rear surface of the concrete construct, and (4) summarize the results.

  10. Protocol for fir tree sampling for provenance studies

    Science.gov (United States)

    Meisel, Thomas; Bandoniene, Donata; Zettl, Daniela

    2014-05-01

    Isotopic (stable and radiogenic) as well as trace element fingerprinting methods used for tracing the geographical origin, rely on databases, that need to contain data sets representative of the measurands of the individual samples for a specific geographic entity. Through this work, we want to assess different sampling strategies for obtaining representative sample of fir trees (Abies sp.). Motivation for this work is the protection of the local Austrian Christmas tree market from wrongly tagged trees of non-Austrian origin. In particular, we studied three typical Christmas trees the most common species sold as Christmas tree, namely Abies nordmanniana (Nordmann Fir), from the same locality in lower Austria. For the initial tests we applied the elemental fingerprinting method, to study the suitability of the different parts of the tree applying ICP-MS analysis after complete acid digestion in a high pressure asher system (HPA-S).Needle samples from each year of life of the tree and stem wood from three different heights were analyzed for their trace element content to prove the repeatability and to find the best sampling protocol. For the analysis of the needles, the natural wax coating had to be removed in order to get reproducible results. For the analysis of stem wood only the bark was removed. As expected the data of all three trees allowed the differentiation of the individual needle ages, but interestingly enough also between the three sampling heights of the needs. Both needles and wood proved to be suitable for successful fingerprinting, but importantly, provided that sample of the same type and ages are compared. The same samples for the three trees will also be used for isotopic analysis studies to better understand the influence of age and sampling height on the representativeness of fir tree samples. Based on elemental fingerprinting alone, a successful discrimination between local (Austrian) and foreign (Danish, Irish) Christmas trees was possible.

  11. Sample size considerations for clinical research studies in nuclear cardiology.

    Science.gov (United States)

    Chiuzan, Cody; West, Erin A; Duong, Jimmy; Cheung, Ken Y K; Einstein, Andrew J

    2015-12-01

    Sample size calculation is an important element of research design that investigators need to consider in the planning stage of the study. Funding agencies and research review panels request a power analysis, for example, to determine the minimum number of subjects needed for an experiment to be informative. Calculating the right sample size is crucial to gaining accurate information and ensures that research resources are used efficiently and ethically. The simple question "How many subjects do I need?" does not always have a simple answer. Before calculating the sample size requirements, a researcher must address several aspects, such as purpose of the research (descriptive or comparative), type of samples (one or more groups), and data being collected (continuous or categorical). In this article, we describe some of the most frequent methods for calculating the sample size with examples from nuclear cardiology research, including for t tests, analysis of variance (ANOVA), non-parametric tests, correlation, Chi-squared tests, and survival analysis. For the ease of implementation, several examples are also illustrated via user-friendly free statistical software.

  12. Predictive Properties of the Gesell School Readiness Screening Test within Samples from Two Treatment Contexts.

    Science.gov (United States)

    Banerji, Madhabi

    The predictive properties of the Gesell School Readiness Screening Test (GSRT) were examined, taking into account the stated purposes of the test and the context of test use. Two samples were used: (1) a control sample of 55 students (21 males and 34 females) whose GSRT scores were not used for placement or tracking; and (2) a treatment sample of…

  13. Theory Testing Using Case Studies

    DEFF Research Database (Denmark)

    Møller, Ann-Kristina Løkke; Dissing Sørensen, Pernille

    2014-01-01

    testing using case studies, including the associated research goal, analysis, and generalisability. We argue that research designs for theory testing using case studies differ from theorybuilding case study research designs because different research projects serve different purposes and follow different......The appropriateness of case studies as a tool for theory testing is still a controversial issue, and discussions about the weaknesses of such research designs have previously taken precedence over those about its strengths. The purpose of the paper is to examine and revive the approach of theory...... research paths....

  14. Comparative Study of element composition of some honey samples ...

    African Journals Online (AJOL)

    The study was carried out at the Federal College of Forestry, Ibadan with seven honey samples were randomly selected within Ibadan metropolis, labeled as: Sample A (Forestry Honey), Sample B(Pure Honey), Sample C (Mr. Honey), Sample D (Taraba Honey), Sample E (Sokoto Honey), Sample F (Saki Honey), and ...

  15. Using re-sampling methods in mortality studies.

    Directory of Open Access Journals (Sweden)

    Igor Itskovich

    Full Text Available Traditional methods of computing standardized mortality ratios (SMR in mortality studies rely upon a number of conventional statistical propositions to estimate confidence intervals for obtained values. Those propositions include a common but arbitrary choice of the confidence level and the assumption that observed number of deaths in the test sample is a purely random quantity. The latter assumption may not be fully justified for a series of periodic "overlapping" studies. We propose a new approach to evaluating the SMR, along with its confidence interval, based on a simple re-sampling technique. The proposed method is most straightforward and requires neither the use of above assumptions nor any rigorous technique, employed by modern re-sampling theory, for selection of a sample set. Instead, we include all possible samples that correspond to the specified time window of the study in the re-sampling analysis. As a result, directly obtained confidence intervals for repeated overlapping studies may be tighter than those yielded by conventional methods. The proposed method is illustrated by evaluating mortality due to a hypothetical risk factor in a life insurance cohort. With this method used, the SMR values can be forecast more precisely than when using the traditional approach. As a result, the appropriate risk assessment would have smaller uncertainties.

  16. Determining sample size and a passing criterion for respirator fit-test panels.

    Science.gov (United States)

    Landsittel, D; Zhuang, Z; Newcomb, W; Berry Ann, R

    2014-01-01

    Few studies have proposed methods for sample size determination and specification of passing criterion (e.g., number needed to pass from a given size panel) for respirator fit-tests. One approach is to account for between- and within- subject variability, and thus take full advantage of the multiple donning measurements within subject, using a random effects model. The corresponding sample size calculation, however, may be difficult to implement in practice, as it depends on the model-specific and test panel-specific variance estimates, and thus does not yield a single sample size or specific cutoff for number needed to pass. A simple binomial approach is therefore proposed to simultaneously determine both the required sample size and the optimal cutoff for the number of subjects needed to achieve a passing result. The method essentially conducts a global search of the type I and type II errors under different null and alternative hypotheses, across the range of possible sample sizes, to find the lowest sample size which yields at least one cutoff satisfying, or approximately satisfying all pre-determined limits for the different error rates. Benchmark testing of 98 respirators (conducted by the National Institute for Occupational Safety and Health) is used to illustrate the binomial approach and show how sample size estimates from the random effects model can vary substantially depending on estimated variance components. For the binomial approach, probability calculations show that a sample size of 35 to 40 yields acceptable error rates under different null and alternative hypotheses. For the random effects model, the required sample sizes are generally smaller, but can vary substantially based on the estimate variance components. Overall, despite some limitations, the binomial approach represents a highly practical approach with reasonable statistical properties.

  17. Case Study: Testing with Case Studies

    Science.gov (United States)

    Herreid, Clyde Freeman

    2015-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses using case studies to test for knowledge or lessons learned.

  18. Neuromuscular dose-response studies: determining sample size.

    Science.gov (United States)

    Kopman, A F; Lien, C A; Naguib, M

    2011-02-01

    Investigators planning dose-response studies of neuromuscular blockers have rarely used a priori power analysis to determine the minimal sample size their protocols require. Institutional Review Boards and peer-reviewed journals now generally ask for this information. This study outlines a proposed method for meeting these requirements. The slopes of the dose-response relationships of eight neuromuscular blocking agents were determined using regression analysis. These values were substituted for γ in the Hill equation. When this is done, the coefficient of variation (COV) around the mean value of the ED₅₀ for each drug is easily calculated. Using these values, we performed an a priori one-sample two-tailed t-test of the means to determine the required sample size when the allowable error in the ED₅₀ was varied from ±10-20%. The COV averaged 22% (range 15-27%). We used a COV value of 25% in determining the sample size. If the allowable error in finding the mean ED₅₀ is ±15%, a sample size of 24 is needed to achieve a power of 80%. Increasing 'accuracy' beyond this point requires increasing greater sample sizes (e.g. an 'n' of 37 for a ±12% error). On the basis of the results of this retrospective analysis, a total sample size of not less than 24 subjects should be adequate for determining a neuromuscular blocking drug's clinical potency with a reasonable degree of assurance.

  19. Sample size requirement in analytical studies for similarity assessment.

    Science.gov (United States)

    Chow, Shein-Chung; Song, Fuyu; Bai, He

    2017-01-01

    For the assessment of biosimilar products, the FDA recommends a stepwise approach for obtaining the totality-of-the-evidence for assessing biosimilarity between a proposed biosimilar product and its corresponding innovative biologic product. The stepwise approach starts with analytical studies for assessing similarity in critical quality attributes (CQAs), which are relevant to clinical outcomes at various stages of the manufacturing process. For CQAs that are the most relevant to clinical outcomes, the FDA requires an equivalence test be performed for similarity assessment based on an equivalence acceptance criterion (EAC) that is obtained using a single test value of some selected reference lots. In practice, we often have extremely imbalanced numbers of reference and test lots available for the establishment of EAC. In this case, to assist the sponsors, the FDA proposed an idea for determining the number of reference lots and the number of test lots required in order not to have imbalanced sample sizes when establishing EAC for the equivalence test based on extensive simulation studies. Along this line, this article not only provides statistical justification of Dong, Tsong, and Weng's proposal, but also proposes an alternative method for sample size requirement for the Tier 1 equivalence test.

  20. Sensitivity of individual and mini-pool nucleic acid testing assessed by dilution of hepatitis B nucleic acid testing yield samples

    Directory of Open Access Journals (Sweden)

    Kabita Chatterjee

    2014-01-01

    Full Text Available Introduction: For nucleic acid testing (NAT of blood donations, either the blood samples can be pooled together in a batch of six or eight prior to testing (mini-pool-NAT [MP-NAT], or the tests can be run on every individual sample (individual donor-NAT [ID-NAT]. It has been debated in various studies whether pooling of samples results in decreased sensitivity of detection as the volume of individual samples gets lesser in a pool. The objective of this study was to investigate the effect of dilution on the sensitivity of tests. Materials and Methods: The study was performed on nine plasma samples which were hepatitis B reactive exclusively by Procleix Ultrio Plus and not by Procleix Ultrio or serology. These nine exclusive UltrioPlus ID-NAT yield samples were diluted in 1:2, 1:4. 1:6 and 1:8 dilutions using previously tested negative plasma and each dilution of every sample along with archived undiluted sample were retested in three replicates with Procleix Ultrio Plus Assay. Results: Among NAT yield samples, 88.88% of the samples were detected when retested in ID-NAT in undiluted form. Samples with higher viral load (sample 5 and 6 were detected by all dilutions. When samples with viral load below 20 IU/mL were tested in dilutions of 1:6 or 1:8, only 9 out of 27 replicates (33.33% were detected. This means that more than 67% of low viral load samples were missed by MP-NAT of 1:6 or 1:8 dilution out of total NAT yield samples. Conclusion: Individual Donor NAT is ideal methodology for NAT as dilution due to pooling may miss samples with low viral load as evident in this study.

  1. Sensitivity of individual and mini-pool nucleic acid testing assessed by dilution of hepatitis B nucleic acid testing yield samples.

    Science.gov (United States)

    Chatterjee, Kabita; Agarwal, Nitin; Coshic, Poonam; Borgohain, Mayuri; Chakroborty, Sourit

    2014-01-01

    For nucleic acid testing (NAT) of blood donations, either the blood samples can be pooled together in a batch of six or eight prior to testing (mini-pool-NAT [MP-NAT]), or the tests can be run on every individual sample (individual donor-NAT [ID-NAT]). It has been debated in various studies whether pooling of samples results in decreased sensitivity of detection as the volume of individual samples gets lesser in a pool. The objective of this study was to investigate the effect of dilution on the sensitivity of tests. The study was performesd on nine plasma samples which were hepatitis B reactive exclusively by Procleix Ultrio Plus and not by Procleix Ultrio or serology. These nine exclusive UltrioPlus ID-NAT yield samples were diluted in 1:2, 1:4. 1:6 and 1:8 dilutions using previously tested negative plasma and each dilution of every sample along with archived undiluted sample were retested in three replicates with Procleix Ultrio Plus Assay. Among NAT yield samples, 88.88% of the samples were detected when retested in ID-NAT in undiluted form. Samples with higher viral load (sample 5 and 6) were detected by all dilutions. When samples with viral load below 20 IU/mL were tested in dilutions of 1:6 or 1:8, only 9 out of 27 replicates (33.33%) were detected. This means that more than 67% of low viral load samples were missed by MP-NAT of 1:6 or 1:8 dilution out of total NAT yield samples. Individual Donor NAT is ideal methodology for NAT as dilution due to pooling may miss samples with low viral load as evident in this study.

  2. Chi-Squared Test of Fit and Sample Size-A Comparison between a Random Sample Approach and a Chi-Square Value Adjustment Method.

    Science.gov (United States)

    Bergh, Daniel

    2015-01-01

    Chi-square statistics are commonly used for tests of fit of measurement models. Chi-square is also sensitive to sample size, which is why several approaches to handle large samples in test of fit analysis have been developed. One strategy to handle the sample size problem may be to adjust the sample size in the analysis of fit. An alternative is to adopt a random sample approach. The purpose of this study was to analyze and to compare these two strategies using simulated data. Given an original sample size of 21,000, for reductions of sample sizes down to the order of 5,000 the adjusted sample size function works as good as the random sample approach. In contrast, when applying adjustments to sample sizes of lower order the adjustment function is less effective at approximating the chi-square value for an actual random sample of the relevant size. Hence, the fit is exaggerated and misfit under-estimated using the adjusted sample size function. Although there are big differences in chi-square values between the two approaches at lower sample sizes, the inferences based on the p-values may be the same.

  3. Optimized testing for C. trachomatis DNA in synovial fluid samples in clinical practice.

    Science.gov (United States)

    Freise, J; Bernau, I; Meier, S; Zeidler, H; Kuipers, J G

    2015-11-01

    No standardized polymerase chain reaction (PCR) assay is available for detection of Chlamydia trachomatis (C. tr.) in synovial fluid (SF) for diagnostic use in clinical practice. This study tested the performance of two optimized molecular biology methods, to determine which is best suited for detecting C. tr. in SF clinical samples from patients with various rheumatologic diseases. Two DNA extraction methods, i.e., (1) alkaline lysis and (2) QIAEX II Gel Extraction Kit® + cetyltrimethylammonium bromide (CTAB; Qiagen, Hilden, Germany), and C. tr.-omp1-152 bp PCR were tested in SF samples from a total of 329 patients with the following diagnoses: reactive arthritis (ReA; n = 10, 4 patients had posturethritic ReA), undifferentiated arthritis (UA; n = 66), rheumatoid arthritis (RA; n = 169), psoriatic arthritis (PSA; n = 12), and osteoarthritis (OA) n = 72. In SF samples, C. tr.-omp1-152 bp PCR in combination with alkaline lysis DNA extraction allowed detection of more C. tr.-positive samples: 3/10 (30%) ReA patients (all with posturethritic ReA) and 20/66 (38%) UA patients were positive, compared to the 0/10 (0%) patients with ReA and 1/66 (2%) with UA detected using the QIAEX II Gel Extraction Kit® + CTAB. Moreover, 2/12 (17%) SF samples from PSA patients tested positive with alkaline lysis. All samples from patients with OA and RA tested negative. Alkaline lysis in combination with C. tr.-omp1-152 bp PCR emerged as the most sensitive method for identification of C. tr. in clinical SF samples.

  4. Sample size for estimation of the Pearson correlation coefficient in cherry tomato tests

    Directory of Open Access Journals (Sweden)

    Bruno Giacomini Sari

    2017-09-01

    Full Text Available ABSTRACT: The aim of this study was to determine the required sample size for estimation of the Pearson coefficient of correlation between cherry tomato variables. Two uniformity tests were set up in a protected environment in the spring/summer of 2014. The observed variables in each plant were mean fruit length, mean fruit width, mean fruit weight, number of bunches, number of fruits per bunch, number of fruits, and total weight of fruits, with calculation of the Pearson correlation matrix between them. Sixty eight sample sizes were planned for one greenhouse and 48 for another, with the initial sample size of 10 plants, and the others were obtained by adding five plants. For each planned sample size, 3000 estimates of the Pearson correlation coefficient were obtained through bootstrap re-samplings with replacement. The sample size for each correlation coefficient was determined when the 95% confidence interval amplitude value was less than or equal to 0.4. Obtaining estimates of the Pearson correlation coefficient with high precision is difficult for parameters with a weak linear relation. Accordingly, a larger sample size is necessary to estimate them. Linear relations involving variables dealing with size and number of fruits per plant have less precision. To estimate the coefficient of correlation between productivity variables of cherry tomato, with a confidence interval of 95% equal to 0.4, it is necessary to sample 275 plants in a 250m² greenhouse, and 200 plants in a 200m² greenhouse.

  5. Variability Study of the S5 Sample

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... We present the results of flux density monitoring of the S5 sample at 5GHz with the Urumqi 25-m radio telescope during Dec. 2008 and Nov. 2009. Most sources exhibited > 2% rms variation in our one-year monitoring. Twenty-five highly variable sources were detected at a confidence level of 99%. Weaker ...

  6. The Study on Mental Health at Work: Design and sampling.

    Science.gov (United States)

    Rose, Uwe; Schiel, Stefan; Schröder, Helmut; Kleudgen, Martin; Tophoven, Silke; Rauch, Angela; Freude, Gabriele; Müller, Grit

    2017-08-01

    The Study on Mental Health at Work (S-MGA) generates the first nationwide representative survey enabling the exploration of the relationship between working conditions, mental health and functioning. This paper describes the study design, sampling procedures and data collection, and presents a summary of the sample characteristics. S-MGA is a representative study of German employees aged 31-60 years subject to social security contributions. The sample was drawn from the employment register based on a two-stage cluster sampling procedure. Firstly, 206 municipalities were randomly selected from a pool of 12,227 municipalities in Germany. Secondly, 13,590 addresses were drawn from the selected municipalities for the purpose of conducting 4500 face-to-face interviews. The questionnaire covers psychosocial working and employment conditions, measures of mental health, work ability and functioning. Data from personal interviews were combined with employment histories from register data. Descriptive statistics of socio-demographic characteristics and logistic regressions analyses were used for comparing population, gross sample and respondents. In total, 4511 face-to-face interviews were conducted. A test for sampling bias revealed that individuals in older cohorts participated more often, while individuals with an unknown educational level, residing in major cities or with a non-German ethnic background were slightly underrepresented. There is no indication of major deviations in characteristics between the basic population and the sample of respondents. Hence, S-MGA provides representative data for research on work and health, designed as a cohort study with plans to rerun the survey 5 years after the first assessment.

  7. Personality Test Validation Research: Present-employee and job applicant samples

    OpenAIRE

    Bradley, Kevin Michael

    2003-01-01

    In an effort to demonstrate the usefulness of personality tests as predictors of job performance, it is common practice to draw a validation sample consisting of individuals who are currently employed on the job in question. It has long been assumed that the results of such a study are appropriately generalized to the setting wherein job candidates respond to personality inventories as an application requirement. The purpose of this manuscript was to critically evaluate the evidence supportin...

  8. Sample size for estimation of the Pearson correlation coefficient in cherry tomato tests

    OpenAIRE

    Bruno Giacomini Sari; Alessandro Dal’Col Lúcio; Cinthya Souza Santana; Dionatan Ketzer Krysczun; André Luís Tischler; Lucas Drebes

    2017-01-01

    ABSTRACT: The aim of this study was to determine the required sample size for estimation of the Pearson coefficient of correlation between cherry tomato variables. Two uniformity tests were set up in a protected environment in the spring/summer of 2014. The observed variables in each plant were mean fruit length, mean fruit width, mean fruit weight, number of bunches, number of fruits per bunch, number of fruits, and total weight of fruits, with calculation of the Pearson correlation matrix b...

  9. EVALUATION OF ARG-1 SAMPLES PREPARED BY CESIUM CARBONATE DISSOLUTION DURING THE ISOLOK SME ACCEPTABILITY TESTING

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, T.; Hera, K.; Coleman, C.

    2011-12-05

    Evaluation of Defense Waste Processing Facility (DWPF) Chemical Process Cell (CPC) cycle time identified several opportunities to improve the CPC processing time. The Mechanical Systems & Custom Equipment Development (MS&CED) Section of the Savannah River National Laboratory (SRNL) recently completed the evaluation of one of these opportunities - the possibility of using an Isolok sampling valve as an alternative to the Hydragard valve for taking DWPF process samples at the Slurry Mix Evaporator (SME). The use of an Isolok for SME sampling has the potential to improve operability, reduce maintenance time, and decrease CPC cycle time. The SME acceptability testing for the Isolok was requested in Task Technical Request (TTR) HLW-DWPF-TTR-2010-0036 and was conducted as outlined in Task Technical and Quality Assurance Plan (TTQAP) SRNLRP-2011-00145. RW-0333P QA requirements applied to the task, and the results from the investigation were documented in SRNL-STI-2011-00693. Measurement of the chemical composition of study samples was a critical component of the SME acceptability testing of the Isolok. A sampling and analytical plan supported the investigation with the analytical plan directing that the study samples be prepared by a cesium carbonate (Cs{sub 2}CO{sub 3}) fusion dissolution method and analyzed by Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP-OES). The use of the cesium carbonate preparation method for the Isolok testing provided an opportunity for an additional assessment of this dissolution method, which is being investigated as a potential replacement for the two methods (i.e., sodium peroxide fusion and mixed acid dissolution) that have been used at the DWPF for the analysis of SME samples. Earlier testing of the Cs{sub 2}CO{sub 3} method yielded promising results which led to a TTR from Savannah River Remediation, LLC (SRR) to SRNL for additional support and an associated TTQAP to direct the SRNL efforts. A technical report resulting

  10. 77 FR 72205 - Testing and Labeling Pertaining to Product Certification Regarding Representative Samples for...

    Science.gov (United States)

    2012-12-05

    ... design or manufacturing process, including the sourcing of component parts,'' and the ``testing of random... representative of the product for mechanical tests. For example, if a bicycle handlebar sample is manufactured... concerning untested units versus tested units may be met by a range of probability-based sampling designs...

  11. 9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

    Science.gov (United States)

    2010-01-01

    ... samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... a representative sample of 30 eggs collected from a single day's production from the flock, must be... IgG antibodies set forth for testing serum in § 147.7 (for these tests the resultant supernatant...

  12. Optimizing human semen cryopreservation by reducing test vial volume and repetitive test vial sampling

    DEFF Research Database (Denmark)

    Jensen, Christian F S; Ohl, Dana A; Parker, Walter R

    2015-01-01

    : Prospective clinical laboratory study. SETTING: University assisted reproductive technology (ART) laboratory. PATIENT(S): A total of 594 patients undergoing semen analysis and cryopreservation. INTERVENTION(S): Semen analysis, cryopreservation with different intermediate steps and in different volumes (50......-1,000 μL), and long-term storage in LN2 or VN2. MAIN OUTCOME MEASURE(S): Optimal TV volume, prediction of cryosurvival (CS) in ART procedure vials (ARTVs) with pre-freeze semen parameters and TV CS, post-thaw motility after two- or three-step semen cryopreservation and cryostorage in VN2 and LN2. RESULT......(S): Test vial volume of 50 μL yielded lower CS than other volumes tested. Cryosurvival of 100 μL was similar to that of larger volumes tested. An intermediate temperature exposure (-88°C to -93°C for 20 minutes) during cryopreservation did not affect post-thaw motility. Cryosurvival of TVs and ARTVs from...

  13. Non-invasive prenatal chromosomal aneuploidy testing--clinical experience: 100,000 clinical samples.

    Science.gov (United States)

    McCullough, Ron M; Almasri, Eyad A; Guan, Xiaojun; Geis, Jennifer A; Hicks, Susan C; Mazloom, Amin R; Deciu, Cosmin; Oeth, Paul; Bombard, Allan T; Paxton, Bill; Dharajiya, Nilesh; Saldivar, Juan-Sebastian

    2014-01-01

    As the first laboratory to offer massively parallel sequencing-based noninvasive prenatal testing (NIPT) for fetal aneuploidies, Sequenom Laboratories has been able to collect the largest clinical population experience data to date, including >100,000 clinical samples from all 50 U.S. states and 13 other countries. The objective of this study is to give a robust clinical picture of the current laboratory performance of the MaterniT21 PLUS LDT. The study includes plasma samples collected from patients with high-risk pregnancies in our CLIA-licensed, CAP-accredited laboratory between August 2012 to June 2013. Samples were assessed for trisomies 13, 18, 21 and for the presence of chromosome Y-specific DNA. Sample data and ad hoc outcome information provided by the clinician was compiled and reviewed to determine the characteristics of this patient population, as well as estimate the assay performance in a clinical setting. NIPT patients most commonly undergo testing at an average of 15 weeks, 3 days gestation; and average 35.1 years of age. The average turnaround time is 4.54 business days and an overall 1.3% not reportable rate. The positivity rate for Trisomy 21 was 1.51%, followed by 0.45% and 0.21% rate for Trisomies 18 and 13, respectively. NIPT positivity rates are similar to previous large clinical studies of aneuploidy in women of maternal age ≥ 35 undergoing amniocentesis. In this population 3519 patients had multifetal gestations (3.5%) with 2.61% yielding a positive NIPT result. NIPT has been commercially offered for just over 2 years and the clinical use by patients and clinicians has increased significantly. The risks associated with invasive testing have been substantially reduced by providing another assessment of aneuploidy status in high-risk patients. The accuracy and NIPT assay positivity rate are as predicted by clinical validations and the test demonstrates improvement in the current standard of care.

  14. Forensic Identification of Human Blood: comparison of two one-step presumptive tests for blood screening of crime scene samples.

    OpenAIRE

    Ana Flávia Belchior Andrade; Maria Emília Cambria Guimaro Siqueira; Luciano Chaves Arantes; Larissa Silva Queiroz; Rayane Luiza Viegas Silva; Eduardo Dias Ramalho

    2014-01-01

    Blood is the most common body fluid found at crime scenes. One-step presumptive tests have been designed as a rapid immunological test for the qualitative detection of human hemoglobin in stool samples (faecal occult blood) their usefulness for forensic purposes has been demonstrated before. In this study we compare Hexagon OBTI kit and FOB One-step Bioeasy kit sensitivity in the analysis of diluted blood samples. With Hexagon OBTI, positive test results are achieved in whole blood dilutions ...

  15. WRAP Module 1 sampling strategy and waste characterization alternatives study

    Energy Technology Data Exchange (ETDEWEB)

    Bergeson, C.L.

    1994-09-30

    The Waste Receiving and Processing Module 1 Facility is designed to examine, process, certify, and ship drums and boxes of solid wastes that have a surface dose equivalent of less than 200 mrem/h. These wastes will include low-level and transuranic wastes that are retrievably stored in the 200 Area burial grounds and facilities in addition to newly generated wastes. Certification of retrievably stored wastes processing in WRAP 1 is required to meet the waste acceptance criteria for onsite treatment and disposal of low-level waste and mixed low-level waste and the Waste Isolation Pilot Plant Waste Acceptance Criteria for the disposal of TRU waste. In addition, these wastes will need to be certified for packaging in TRUPACT-II shipping containers. Characterization of the retrievably stored waste is needed to support the certification process. Characterization data will be obtained from historical records, process knowledge, nondestructive examination nondestructive assay, visual inspection of the waste, head-gas sampling, and analysis of samples taken from the waste containers. Sample characterization refers to the method or methods that are used to test waste samples for specific analytes. The focus of this study is the sample characterization needed to accurately identify the hazardous and radioactive constituents present in the retrieved wastes that will be processed in WRAP 1. In addition, some sampling and characterization will be required to support NDA calculations and to provide an over-check for the characterization of newly generated wastes. This study results in the baseline definition of WRAP 1 sampling and analysis requirements and identifies alternative methods to meet these requirements in an efficient and economical manner.

  16. The outcome of dimethylglyoxime testing in a sample of cell phones in Denmark

    DEFF Research Database (Denmark)

    Thyssen, Jacob Pontoppidan; Johansen, Jeanne D; Zachariae, Claus

    2008-01-01

    : 5 of 15 (33.3%) phones from company A and 3 of 26 (11.5%) phones from company B showed at least 1 positive reaction. 3 phones had more than 1 positive DMG spots. CONCLUSIONS: This study documents that excessive nickel release (i.e. a positive DMG test) is relatively frequent in a sample of cell......BACKGROUND: Nickel dermatitis may be caused by frequent and prolonged use of cell phones. Because little is known about the frequency of nickel release from cell phones, it is difficult to estimate the risk of nickel sensitization and dermatitis among their users. OBJECTIVE: Inspired by a recent...... case of nickel dermatitis from prolonged cell phone use, the frequency of dimethylglyoxime (DMG)-positive cell phones on the Danish market was investigated. METHODS: Five major cell phone companies were contacted. Two were visited, and the DMG test was performed on a sample of their products. RESULTS...

  17. The outcome of dimethylglyoxime testing in a sample of cell phones in Denmark

    DEFF Research Database (Denmark)

    Thyssen, J.P.; Johansen, J.D.; Zachariae, C.

    2008-01-01

    : 5 of 15 (33.3%) phones from company A and 3 of 26 (11.5%) phones from company B showed at least 1 positive reaction. 3 phones had more than 1 positive DMG spots. Conclusions: This study documents that excessive nickel release (i.e. a positive DMG test) is relatively frequent in a sample of cell......Background: Nickel dermatitis may be caused by frequent and prolonged use of cell phones. Because little is known about the frequency of nickel release from cell phones, it is difficult to estimate the risk of nickel sensitization and dermatitis among their users. Objective: Inspired by a recent...... case of nickel dermatitis from prolonged cell phone use, the frequency of dimethylglyoxime (DMG)-positive cell phones on the Danish market was investigated. Methods: Five major cell phone companies were contacted. Two were visited, and the DMG test was performed on a sample of their products. Results...

  18. A typical proficiency testing programmes sample design for electrical and electronic product

    Science.gov (United States)

    Wang, T. T.; Zhang, H.; Xie, L. L.; Wang, Y. Y.

    2017-04-01

    Creepage distance and clearance testing are the basic testing items in the safety standards for almost all electrical and electronic products. A typical sample group is designed in this paper for the purpose of proficiency testing programmes. The sample group is composed of two kinds of circuit board. The length of the creepage distance of the two circuit boards in pollution degree 2 and 3 are the same but with different paths. This sample group includes three testing points. This sample group is designed beneficial for numerical statistics and avoiding the data complicity in the laboratory. It can be used for effective laboratory monitoring.

  19. Cavitation Erosion Tests Performed by Indirect Vibratory Method on Stainless Steel Welded Samples with Hardened Surface

    Directory of Open Access Journals (Sweden)

    Marian-Dumitru Nedeloni

    2012-09-01

    Full Text Available The paper presents the results of cavitation erosion tests performed on two types of samples. The materials of the samples are frequently used for manufacturing and repairs of the hydro turbines components submitted to cavitation. The first sample was made by welding of an austenitic stainless steel on austenito-feritic base material. The second sample was made similarly with the first but with a martensitic base material. After the welding processes, on both samples was applied a hardening treatment by surface peening. The cavitation erosion tests were performed on vibratory equipment using the indirect method with stationary specimen. The results show a good cavitation erosion resistance on both samples.

  20. Shrinkage-based diagonal Hotelling’s tests for high-dimensional small sample size data

    KAUST Repository

    Dong, Kai

    2015-09-16

    DNA sequencing techniques bring novel tools and also statistical challenges to genetic research. In addition to detecting differentially expressed genes, testing the significance of gene sets or pathway analysis has been recognized as an equally important problem. Owing to the “large pp small nn” paradigm, the traditional Hotelling’s T2T2 test suffers from the singularity problem and therefore is not valid in this setting. In this paper, we propose a shrinkage-based diagonal Hotelling’s test for both one-sample and two-sample cases. We also suggest several different ways to derive the approximate null distribution under different scenarios of pp and nn for our proposed shrinkage-based test. Simulation studies show that the proposed method performs comparably to existing competitors when nn is moderate or large, but it is better when nn is small. In addition, we analyze four gene expression data sets and they demonstrate the advantage of our proposed shrinkage-based diagonal Hotelling’s test.

  1. The effect of sample handling on cross sectional HIV incidence testing results.

    Directory of Open Access Journals (Sweden)

    Oliver Laeyendecker

    Full Text Available To determine if mishandling prior to testing would make a sample from a chronically infected subject appear recently infected when tested by cross-sectional HIV incidence assays.Serum samples from 31 subjects with chronic HIV infection were tested. Samples were subjected to different handling conditions, including incubation at 4 °C, 25 °C and 37 °C, for 1, 3, 7 or 15 days prior to testing. Samples were also subjected to 1,3, 7 and 15 freeze-thaw cycles prior to testing. Samples were tested using the BED capture enzyme immuno assay (BED-CEIA, Vironostika-less sensitive (V-LS, and an avidity assay using the Genetic Systems HIV-1/HIV-2 plus O EIA (avidity assay.Compared to the sample that was not subjected to any mishandling conditions, for the BED-CEIA, V-LS and avidity assay, there was no significant change in test results for samples incubated at 4 °C or 25 °C prior to testing. No impact on test results occurred after 15 freeze-thaw cycles. A decrease in assay results was observed when samples were held for 3 days or longer at 37 °C prior to testing.Samples can be subjected up to 15 freeze-thaw cycles without affecting the results the BED-CEIA, Vironostika-LS, or avidity assays. Storing samples at 4 °C or 25 °C for up to fifteen days prior to testing had no impact on test results. However, storing samples at 37°C for three or more days did affect results obtained with these assays.

  2. Testing to evaluate synergistic effects from LOCA environments. Test IX. Simultaneous mode; cables, splice assemblies, and electrical insulation samples

    Energy Technology Data Exchange (ETDEWEB)

    Thome, F.V.

    1978-04-01

    This test was conducted to complement Test VIII which was a sequential test of cables, cable splices, and insulation samples. In this test, the generic LOCA environments (radiation, temperature, pressure, chemical spray) were simulated and simultaneously applied to the test items. There were no failures of any assemblies and all were able to function at rated current and voltage throughout the entire test. An additional parameter, dissipation factor, was monitored in this test and when used in conjunction with capacitance, provided a better indication of insulation degradation.

  3. Novel device to sample the esophageal microbiome--the esophageal string test.

    Directory of Open Access Journals (Sweden)

    Sophie A Fillon

    Full Text Available A growing number of studies implicate the microbiome in the pathogenesis of intestinal inflammation. Previous work has shown that adults with esophagitis related to gastroesophageal reflux disease have altered esophageal microbiota compared to those who do not have esophagitis. In these studies, sampling of the esophageal microbiome was accomplished by isolating DNA from esophageal biopsies obtained at the time of upper endoscopy. The aim of the current study was to identify the esophageal microbiome in pediatric individuals with normal esophageal mucosa using a minimally invasive, capsule-based string technology, the Enterotest™. We used the proximal segment of the Enterotest string to sample the esophagus, and term this the "Esophageal String Test" (EST. We hypothesized that the less invasive EST would capture mucosal adherent bacteria present in the esophagus in a similar fashion as mucosal biopsy. EST samples and mucosal biopsies were collected from children with no esophageal inflammation (n = 15 and their microbiome composition determined by 16S rRNA gene sequencing. Microbiota from esophageal biopsies and ESTs produced nearly identical profiles of bacterial genera and were different from the bacterial contents of samples collected from the nasal and oral cavity. We conclude that the minimally invasive EST can serve as a useful device for study of the esophageal microbiome.

  4. Sample size determinations for Welch's test in one-way heteroscedastic ANOVA.

    Science.gov (United States)

    Jan, Show-Li; Shieh, Gwowen

    2014-02-01

    For one-way fixed effects ANOVA, it is well known that the conventional F test of the equality of means is not robust to unequal variances, and numerous methods have been proposed for dealing with heteroscedasticity. On the basis of extensive empirical evidence of Type I error control and power performance, Welch's procedure is frequently recommended as the major alternative to the ANOVA F test under variance heterogeneity. To enhance its practical usefulness, this paper considers an important aspect of Welch's method in determining the sample size necessary to achieve a given power. Simulation studies are conducted to compare two approximate power functions of Welch's test for their accuracy in sample size calculations over a wide variety of model configurations with heteroscedastic structures. The numerical investigations show that Levy's (1978a) approach is clearly more accurate than the formula of Luh and Guo (2011) for the range of model specifications considered here. Accordingly, computer programs are provided to implement the technique recommended by Levy for power calculation and sample size determination within the context of the one-way heteroscedastic ANOVA model. © 2013 The British Psychological Society.

  5. QUALITY CONTROL TESTING OF VARIOUS SAMPLES OF PEPPERMINT OIL COLLECTED FROM LOCAL MARKET OF KARACHI, PAKISTAN

    Directory of Open Access Journals (Sweden)

    Shaukat Khalid

    2016-06-01

    Full Text Available Menthol is the most commonly used substance in many cosmetics and pharmaceutical products either as an active ingredient or in the form of excipient. In the present study, different samples of commercially available peppermint oil were subjected to standardization by determination of physicochemical characteristics, acid value, and resinified oil content. Thin layer chromatography (TLC has been used to confirm the presence of menthol. The result showed that the quality control test performed for the evaluation of the physicochemical parameters of peppermint oil can be considered useful in its standardization. The results of acid value and the resinified oil tests, carried out on the raw material, have found to be within the standard limits. The results indicated specified number of free fatty acids and absence of greasy impurities. The data obtained from the study would be useful in the authentication of the commercial peppermint oil samples. In TLC studies, the Rf value of the active constituent has been determined by comparison with its standard spot. This technique may be used as a tool for the correct identification of the active constituent which could help in the standardization of the peppermint oil samples.

  6. Bovine milk sampling efficiency for pregnancy-associated glycoproteins (PAG) detection test

    Energy Technology Data Exchange (ETDEWEB)

    Silva, H. K. da; Cassoli, L.D.; Pantoja, J.F.C.; Cerqueira, P.H.R.; Coitinho, T.B.; Machado, P.F.

    2016-07-01

    Two experiments were conducted to verify whether the time of day at which a milk sample is collected and the possible carryover in the milking system may affect pregnancy-associated glycoproteins (PAG) levels and, consequently, the pregnancy test results in dairy cows. In experiment one, we evaluated the effect of time of day at which the milk sample is collected from 51 cows. In experiment two, which evaluated the possible occurrence of carryover in the milk meter milking system, milk samples from 94 cows belonging to two different farms were used. The samples were subjected to pregnancy test using ELISA methodology to measure PAG concentrations and to classify the samples as positive (pregnant), negative (nonpregnant), or suspicious (recheck). We found that the time of milking did not affect the PAG levels. As to the occurrence of carryover in the milk meter, the PAG levels of the samples collected from Farm-2 were heavily influenced by a carryover effect compared with the samples from Farm-1. Thus, milk samples submitted to a pregnancy test can be collected during the morning or the evening milking. When the sample is collected from the milk meters, periodic equipment maintenance should be noted, including whether the milk meter is totally drained between different animals’ milking and equipment cleaning between milking is performed correctly to minimize the occurrence of carryover, thereby avoiding the effect on PAG levels and, consequently, the pregnancy test results. Therefore, a single milk sample can be used for both milk quality tests and pregnancy test.

  7. Toxicity Tests of Whole Sediment Samples Using the Hyallella (H. azteca) Survival and Growth Tests (ASTM E 1283-93)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — 10-day toxicity tests using Hyalella azteca were conducted with sediment samples collected by the U.S. Fish & Wildlife Service, Bloomington, Indiana facility to...

  8. 75 FR 16874 - Market Test of “Samples Co-Op Box” Experimental Product

    Science.gov (United States)

    2010-04-02

    ... From the Federal Register Online via the Government Publishing Office POSTAL SERVICE Market Test of ``Samples Co-Op Box'' Experimental Product AGENCY: Postal Service TM . ACTION: Notice. SUMMARY...) that it will begin a market test of its ``Samples Co-Op Box'' experimental product on May 1, 2010. The...

  9. Group SkSP-R sampling plan for accelerated life tests

    Indian Academy of Sciences (India)

    Muhammad Aslam

    2017-09-15

    Sep 15, 2017 ... Reliability can be assured only when one lot of items has been accepted or rejected on the basis of a suitably designed sampling plan. An effective implementation of any life test is possible through proper sampling plan. Usually, a life test is more expensive and time-consuming as one need to wait till the ...

  10. Patterns of oribatid mite species diversity: testing the effects of elevation, area and sampling effort.

    Science.gov (United States)

    Mumladze, Levan; Murvanidze, Maka; Maraun, Mark

    2017-07-01

    Elevational gradients in species diversity and species area relationships are two well established patterns that are not mutually exclusive in space and time. Elevation and area are both considered as good proxies to detect and characterize the patterns of species diversity distribution. However, such studies are hampered by the incomplete biodiversity data available for ecologists, which may affect the pattern perceptions. Using the large dataset of oribatid mite communities sampled in Georgia, we tested the effects of altitude and area on species distribution using various approaches, while explicitly considering the biases from sampling effort. Our results showed that elevation and area are strongly correlated (with increasing absolute elevation, land area decreases) and both have strong linear effects on species diversity distribution when studied separately. Approaches based on multiple regression and direct removal of co-varied factors, indicated that the effect of area can actually override the effect of elevation in describing the oribatid species diversity distribution along with elevation. On the other hand, the bias of sampling proved significant in perception of elevational species richness pattern with less effect on elevational species area relationship. We suggest that the sampling alone may be responsible for patterns observed and thus should be considered in ecological studies when eligible.

  11. Optimal sample sizes for Welch's test under various allocation and cost considerations.

    Science.gov (United States)

    Jan, Show-Li; Shieh, Gwowen

    2011-12-01

    The issue of the sample size necessary to ensure adequate statistical power has been the focus of considerableattention in scientific research. Conventional presentations of sample size determination do not consider budgetary and participant allocation scheme constraints, although there is some discussion in the literature. The introduction of additional allocation and cost concerns complicates study design, although the resulting procedure permits a practical treatment of sample size planning. This article presents exact techniques for optimizing sample size determinations in the context of Welch (Biometrika, 29, 350-362, 1938) test of the difference between two means under various design and cost considerations. The allocation schemes include cases in which (1) the ratio of group sizes is given and (2) one sample size is specified. The cost implications suggest optimally assigning subjects (1) to attain maximum power performance for a fixed cost and (2) to meet adesignated power level for the least cost. The proposed methods provide useful alternatives to the conventional procedures and can be readily implemented with the developed R and SAS programs that are available as supplemental materials from brm.psychonomic-journals.org/content/supplemental.

  12. Electrofracturing test system and method of determining material characteristics of electrofractured material samples

    Science.gov (United States)

    Bauer, Stephen J.; Glover, Steven F.; Pfeifle, Tom; Su, Jiann-Cherng; Williamson, Kenneth Martin; Broome, Scott Thomas; Gardner, William Payton

    2017-08-01

    A device for electrofracturing a material sample and analyzing the material sample is disclosed. The device simulates an in situ electrofracturing environment so as to obtain electrofractured material characteristics representative of field applications while allowing permeability testing of the fractured sample under in situ conditions.

  13. Replicating studies in which samples of participants respond to samples of stimuli.

    Science.gov (United States)

    Westfall, Jacob; Judd, Charles M; Kenny, David A

    2015-05-01

    In a direct replication, the typical goal is to reproduce a prior experimental result with a new but comparable sample of participants in a high-powered replication study. Often in psychology, the research to be replicated involves a sample of participants responding to a sample of stimuli. In replicating such studies, we argue that the same criteria should be used in sampling stimuli as are used in sampling participants. Namely, a new but comparable sample of stimuli should be used to ensure that the original results are not due to idiosyncrasies of the original stimulus sample, and the stimulus sample must often be enlarged to ensure high statistical power. In support of the latter point, we discuss the fact that in experiments involving samples of stimuli, statistical power typically does not approach 1 as the number of participants goes to infinity. As an example of the importance of sampling new stimuli, we discuss the bygone literature on the risky shift phenomenon, which was almost entirely based on a single stimulus sample that was later discovered to be highly unrepresentative. We discuss the use of both resampled and expanded stimulus sets, that is, stimulus samples that include the original stimuli plus new stimuli. © The Author(s) 2015.

  14. NASA-STD-6001B Test 1 Upward Flame Propagation; Sample Length Impact on MOC Investigation

    Science.gov (United States)

    Harper, Susana Tapia; Juarez, Alfredo; Woods, Brenton L.; Beeson, Harold D.

    2017-01-01

    Understanding the combustion behavior of materials in the elevated oxygen environments of habitable spacecraft is of utmost importance to crew safety and mission success. Currently, certification for unrestricted flight usage of a material with respect to flammability involves passing the Upward Flame Propagation Test of NASA-STD-6001B (Test 1). This test evaluates materials in a standardized test configuration for two failure criteria: self-extinguishment within 15 cm (6 in.) and the propensity of flame propagation by means of flaming material transfer. By the NASA standard, full-length samples are 30 cm (12 in.) in length; however, factors independent of the test method such as limited material availability or various nonstandard test configurations limit the full pretest sample lengths available for test. This paper characterizes the dependence, if any, of pretest sample length on NASA-STD-6001B Test 1 results. Testing was performed using the Maximum Oxygen Concentration (MOC) Threshold Method to obtain a data set for each sample length tested. In addition, various material types, including cloth (Nomex), foam (TA-301) and solids (Ultem), were tested to investigate potential effects of test specimen types. Though additional data needs to be generated to provide statistical confidence, preliminary findings are that use of variable sample lengths has minimal impact on NASA-STD-6001B flammability performance and MOC determination.

  15. Sampling

    CERN Document Server

    Thompson, Steven K

    2012-01-01

    Praise for the Second Edition "This book has never had a competitor. It is the only book that takes a broad approach to sampling . . . any good personal statistics library should include a copy of this book." —Technometrics "Well-written . . . an excellent book on an important subject. Highly recommended." —Choice "An ideal reference for scientific researchers and other professionals who use sampling." —Zentralblatt Math Features new developments in the field combined with all aspects of obtaining, interpreting, and using sample data Sampling provides an up-to-date treat

  16. Two-Sample Tests for High-Dimensional Linear Regression with an Application to Detecting Interactions.

    Science.gov (United States)

    Xia, Yin; Cai, Tianxi; Cai, T Tony

    2018-01-01

    Motivated by applications in genomics, we consider in this paper global and multiple testing for the comparisons of two high-dimensional linear regression models. A procedure for testing the equality of the two regression vectors globally is proposed and shown to be particularly powerful against sparse alternatives. We then introduce a multiple testing procedure for identifying unequal coordinates while controlling the false discovery rate and false discovery proportion. Theoretical justifications are provided to guarantee the validity of the proposed tests and optimality results are established under sparsity assumptions on the regression coefficients. The proposed testing procedures are easy to implement. Numerical properties of the procedures are investigated through simulation and data analysis. The results show that the proposed tests maintain the desired error rates under the null and have good power under the alternative at moderate sample sizes. The procedures are applied to the Framingham Offspring study to investigate the interactions between smoking and cardiovascular related genetic mutations important for an inflammation marker.

  17. Evidentials and advertising: a sample study

    Directory of Open Access Journals (Sweden)

    Laura Cruz García

    2017-07-01

    Full Text Available This paper explores the use of evidential devices in press adverts in English in a compilation of original advertisements. Due to the appellative nature of advertising discourse, I think that these texts are likely to convey source of knowledge through evidentials as an advertising strategy in order to pragmatically manifest a higher level of credibility and reliability of the information presented concerning the products and the brands. The selected corpus of adverts will allow us to focus special attention on this particular genre and on how evidentials are used, in the fashion of other works carried out in other textual genres (cf. Fox, 2001; Kaplan, 2007; Marín-Arrese, 2004, 2007; Ortega-Barrera and Torres-Ramírez, 2010. Evidentials are studied as part of a set of persuasion strategies used by different linguistic communities in the discourse of advertising (Block de Behar, 1992; Cook, 1992; Cortés de los Ríos, 2001; Pavitt, 2000; Rein, 1982. Conclusions will report on how evidentials are used in print adverts, and whether a type of evidential device prevails over the rest.

  18. A General Asymptotic Framework for Distribution-Free Graph-Based Two-Sample Tests

    OpenAIRE

    Bhattacharya, Bhaswar B.

    2015-01-01

    Testing equality of two multivariate distributions is a classical problem for which many non-parametric tests have been proposed over the years. Most of the popular two-sample tests, which are asymptotically distribution-free, are based either on geometric graphs constructed using inter-point distances between the observations (multivariate generalizations of the Wald-Wolfowitz's runs test) or on multivariate data-depth (generalizations of the Mann-Whitney rank test). This paper introduces a ...

  19. Filtration and Leach Testing for REDOX Sludge and S-Saltcake Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Shimskey, Rick W.; Billing, Justin M.; Buck, Edgar C.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Geeting, John GH; Hallen, Richard T.; Jenson, Evan D.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Snow, Lanee A.; Swoboda, Robert G.

    2009-02-20

    A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan.( ) The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Under test plan TP-RPP-WTP-467, eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. Under this test plan, a waste-testing program was implemented that included: • Homogenizing the archive samples by group as defined in the test plan • Characterizing the homogenized sample groups • Performing parametric leaching testing on each group for compounds of interest • Performing bench-top filtration/leaching tests in the hot cell for each group to simulate filtration and leaching activities if they occurred in the UFP2 vessel of the WTP Pretreatment Facility. This report focuses on filtration/leaching tests performed on two of the eight waste composite samples and follow-on parametric tests to support aluminum leaching results from those tests.

  20. Freeze-bond strength experiments,: radially confined compression tests on saline and fresh water samples.

    OpenAIRE

    Bueide, Ida Mari

    2014-01-01

    This thesis presents and analyses the method and results from strength experiments on freeze- bonds conducted on radially confined cylindrical samples (tri-axial tests). In total sixty samples were tested successfully, divided on twenty configurations. The variables consisted of confinement, submersion time, initial temperature and salinity (8 configurations with fresh water ice and 12 with 2-3ppt saline ice). The test set-up was similar to that of Møllegaard [2012] and Shafrova and Høyland [...

  1. A mechanistic test of nicotine replacement therapy sampling for smoking cessation induction.

    Science.gov (United States)

    Burris, Jessica L; Heckman, Bryan W; Mathew, Amanda R; Carpenter, Matthew J

    2015-06-01

    Studies that explore the mechanisms of treatment effect are needed in the area of smoking cessation induction, the primary goal of which is to promote the occurrence of a quit attempt among individuals who report little interest in smoking cessation. This study tested the mediational effect of 5 psychological variables (motivation to quit, abstinence self-efficacy, knowledge of nicotine replacement therapy (NRT), and both positive and negative attitudes toward NRT) on the relationship between NRT sampling and smoking outcomes. Adults who reported low levels of intention to quit in the next month (n = 593) were recruited for a nationwide randomized clinical trial of NRT sampling. Participants provided self-report data via telephone interview on multiple occasions, with the final follow-up at 6 months. Motivation to quit, and to a lesser degree, abstinence self-efficacy at the end of the 6-week intervention best accounted for the effect of NRT sampling as a promoter of quit attempts, smoking reduction, and 7-day point prevalence abstinence. Providing smokers with free NRT samples, in addition to encouraging them to engage in temporary abstinence, results in meaningful change in motivation and self-efficacy, which in turn influence smoking outcomes. Cessation induction interventions should aim to increase motivation to quit and abstinence self-efficacy, above and beyond any efforts to increase knowledge or prompt attitudinal shifts. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  2. Genotoxicity assessment of water sampled from R-11 reservoir by means of allium test

    Energy Technology Data Exchange (ETDEWEB)

    Bukatich, E.; Pryakhin, E. [Urals Research Center for Radiation Medicine (Russian Federation); Geraskin, S. [Russian Institute of Agricultural Radiology and Agroecology (Russian Federation)

    2014-07-01

    The Mayak PA was the first enterprise for the production of weapon-grade plutonium in Russia and it incorporates uranium-graphite reactors for plutonium production and radiochemical facilities for its separation. Radiochemical processing resulted in huge volumes of liquid radioactive wastes of different specific activities. To reduce the radionuclides release into the environment, a system of bypasses and ponds (the Techa Cascade Reservoirs system) to store low-activity liquid wastes has been constructed in the upper reaches of the Techa River. Currently, industrial reservoirs of Mayak PA contain over 350 million m{sup 3} of low-level radioactive liquid wastes with total activity over 7.4 x 10{sup 15} Bq. Reservoir R-11 is the final reservoir in the Techa Cascade Reservoirs system. The average specific activity of main radionuclides in the water of R-11 are: {sup 90}Sr - 1.4x10{sup 3} Bq/l; {sup 137}Cs - 3 Bq/l; {sup 3}H - 7x10{sup 2} Bq/l; α-emitting radionuclides - 2.6 x 10{sup -1} Bq/l. In our study the Allium-test was employed to estimate reservoir R-11 water genotoxic effects. In 2012, 3 water samples were collected in different parts of reservoir R-11. Water samples from the Shershnevskoye reservoir (artificial reservoir on the Miass River designed for Chelyabinsk city water supply) were used as natural control. Samples of distilled and bottled water were used as an additional laboratory control. The common onion, Allium cepa L. (Stuttgarter Riesen) was used. Healthy equal-sized bulbs were soaked for 24 hours at +4±2 deg. C to synchronize cell division. The bulbs were maintained in distilled water at +23 deg. C until roots have grown up to 2±1 mm length and then plunged into water samples. Control samples remained in distilled and bottled water as well as in water samples from the Shershnevskoye reservoir (natural control). Roots of the 18±3 mm length were randomly sampled and fixed in an alcohol/acetic acid mixture. For microscopic analysis, squashed

  3. An empirical test of Maslow's theory of need hierarchy using hologeistic comparison by statistical sampling.

    Science.gov (United States)

    Davis-Sharts, J

    1986-10-01

    Maslow's hierarchy of basic human needs provides a major theoretical framework in nursing science. The purpose of this study was to empirically test Maslow's need theory, specifically at the levels of physiological and security needs, using a hologeistic comparative method. Thirty cultures taken from the 60 cultural units in the Health Relations Area Files (HRAF) Probability Sample were found to have data available for examining hypotheses about thermoregulatory (physiological) and protective (security) behaviors practiced prior to sleep onset. The findings demonstrate there is initial worldwide empirical evidence to support Maslow's need hierarchy.

  4. Non-Invasive Prenatal Chromosomal Aneuploidy Testing - Clinical Experience: 100,000 Clinical Samples

    Science.gov (United States)

    McCullough, Ron M.; Almasri, Eyad A.; Guan, Xiaojun; Geis, Jennifer A.; Hicks, Susan C.; Mazloom, Amin R.; Deciu, Cosmin; Oeth, Paul; Bombard, Allan T.; Paxton, Bill; Dharajiya, Nilesh; Saldivar, Juan-Sebastian

    2014-01-01

    Objective As the first laboratory to offer massively parallel sequencing-based noninvasive prenatal testing (NIPT) for fetal aneuploidies, Sequenom Laboratories has been able to collect the largest clinical population experience data to date, including >100,000 clinical samples from all 50 U.S. states and 13 other countries. The objective of this study is to give a robust clinical picture of the current laboratory performance of the MaterniT21 PLUS LDT. Study Design The study includes plasma samples collected from patients with high-risk pregnancies in our CLIA–licensed, CAP-accredited laboratory between August 2012 to June 2013. Samples were assessed for trisomies 13, 18, 21 and for the presence of chromosome Y-specific DNA. Sample data and ad hoc outcome information provided by the clinician was compiled and reviewed to determine the characteristics of this patient population, as well as estimate the assay performance in a clinical setting. Results NIPT patients most commonly undergo testing at an average of 15 weeks, 3 days gestation; and average 35.1 years of age. The average turnaround time is 4.54 business days and an overall 1.3% not reportable rate. The positivity rate for Trisomy 21 was 1.51%, followed by 0.45% and 0.21% rate for Trisomies 18 and 13, respectively. NIPT positivity rates are similar to previous large clinical studies of aneuploidy in women of maternal age ≥35 undergoing amniocentesis. In this population 3519 patients had multifetal gestations (3.5%) with 2.61% yielding a positive NIPT result. Conclusion NIPT has been commercially offered for just over 2 years and the clinical use by patients and clinicians has increased significantly. The risks associated with invasive testing have been substantially reduced by providing another assessment of aneuploidy status in high-risk patients. The accuracy and NIPT assay positivity rate are as predicted by clinical validations and the test demonstrates improvement in the current standard of care

  5. Non-invasive prenatal chromosomal aneuploidy testing--clinical experience: 100,000 clinical samples.

    Directory of Open Access Journals (Sweden)

    Ron M McCullough

    Full Text Available OBJECTIVE: As the first laboratory to offer massively parallel sequencing-based noninvasive prenatal testing (NIPT for fetal aneuploidies, Sequenom Laboratories has been able to collect the largest clinical population experience data to date, including >100,000 clinical samples from all 50 U.S. states and 13 other countries. The objective of this study is to give a robust clinical picture of the current laboratory performance of the MaterniT21 PLUS LDT. STUDY DESIGN: The study includes plasma samples collected from patients with high-risk pregnancies in our CLIA-licensed, CAP-accredited laboratory between August 2012 to June 2013. Samples were assessed for trisomies 13, 18, 21 and for the presence of chromosome Y-specific DNA. Sample data and ad hoc outcome information provided by the clinician was compiled and reviewed to determine the characteristics of this patient population, as well as estimate the assay performance in a clinical setting. RESULTS: NIPT patients most commonly undergo testing at an average of 15 weeks, 3 days gestation; and average 35.1 years of age. The average turnaround time is 4.54 business days and an overall 1.3% not reportable rate. The positivity rate for Trisomy 21 was 1.51%, followed by 0.45% and 0.21% rate for Trisomies 18 and 13, respectively. NIPT positivity rates are similar to previous large clinical studies of aneuploidy in women of maternal age ≥ 35 undergoing amniocentesis. In this population 3519 patients had multifetal gestations (3.5% with 2.61% yielding a positive NIPT result. CONCLUSION: NIPT has been commercially offered for just over 2 years and the clinical use by patients and clinicians has increased significantly. The risks associated with invasive testing have been substantially reduced by providing another assessment of aneuploidy status in high-risk patients. The accuracy and NIPT assay positivity rate are as predicted by clinical validations and the test demonstrates improvement in the

  6. Performances on Symbol Digit Modalities Test, Color Trails Test, and modified Stroop test in a healthy, elderly Danish sample

    DEFF Research Database (Denmark)

    Vogel, Asmus; Stokholm, Jette; Jørgensen, Kasper

    2013-01-01

    for different age groups. For SDMT and CTT1, Danish Adult Reading Test (DART) score also had a significant impact on test performances. The incongruent version of the modified Stroop test was significantly correlated to education. Moderate and significant correlations were found between the three tests. Even...

  7. Exploring Alternative Test Form Linking Designs with Modified Equating Sample Size and Anchor Test Length. Research Report. ETS RR-13-02

    Science.gov (United States)

    Wang, Lin; Qian, Jiahe; Lee, Yi-Hsuan

    2013-01-01

    The purpose of this study was to evaluate the combined effects of reduced equating sample size and shortened anchor test length on item response theory (IRT)-based linking and equating results. Data from two independent operational forms of a large-scale testing program were used to establish the baseline results for evaluating the results from…

  8. Development of a luminescent mutagenicity test for high-throughput screening of aquatic samples

    NARCIS (Netherlands)

    Zwart, Nick; Lamoree, Marja H.; Houtman, Corine J.; de Boer, Jacob; Kool, Jeroen; Hamers, Timo

    2018-01-01

    The Salmonella reversion based Ames test is the most widely used method for mutagenicity testing. For rapid toxicity assessment of e.g. water samples and for effect-directed analysis, however, the Ames test suffers from lack of throughput and is regarded as a laborious, time consuming method. To

  9. On the matched pairs sign test using bivariate ranked set sampling ...

    African Journals Online (AJOL)

    Our numerical and theoretical results indicate that using BVRSS for the matched pairs sign test is substantially more efficient than using BVSRS. Illustration using palm trees data from sultanate of Oman is provided. Key words: Bootstrap method, bivariate ranked set sample, power of the test, P-value of the test, Pitman's ...

  10. 40 CFR 146.66 - Logging, sampling, and testing prior to new well operation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Logging, sampling, and testing prior... STANDARDS Criteria and Standards Applicable to Class I Hazardous Waste Injection Wells § 146.66 Logging... pump test; or (2) Injectivity tests. (f) The Director shall have the opportunity to witness all logging...

  11. 77 FR 7109 - Establishment of User Fees for Filovirus Testing of Nonhuman Primate Liver Samples

    Science.gov (United States)

    2012-02-10

    ... rulemaking. Laboratory testing of suspected NHPs and early detection of infected animals within the... offering this same service in the future. The testing of non-human primate samples is necessary to prevent... HUMAN SERVICES 42 CFR Part 71 RIN 0920-AA47 Establishment of User Fees for Filovirus Testing of Nonhuman...

  12. 77 FR 6971 - Establishment of User Fees for Filovirus Testing of Nonhuman Primate Liver Samples

    Science.gov (United States)

    2012-02-10

    ... rulemaking. Laboratory testing of suspected NHPs and early detection of infected animals within the... offering this same service in the future. The testing of non-human primate samples is necessary to prevent... HUMAN SERVICES 42 CFR Part 71 RIN 0920-AA47 Establishment of User Fees for Filovirus Testing of Nonhuman...

  13. 46 CFR 160.010-7 - Methods of sampling, inspections and tests.

    Science.gov (United States)

    2010-10-01

    ... manufacturer— (1) Uses the same plastic buoyancy foam used in previous production lots, (2) Determines that the... plastic buoyancy foam controls permitted as an alternative to the buoyancy test in paragraph (e) of this... Vessels § 160.010-7 Methods of sampling, inspections and tests. (a) General. Production tests must be...

  14. First Total Reflection X-Ray Fluorescence round-robin test of water samples: Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Borgese, Laura; Bilo, Fabjola [Chemistry for Technologies Laboratory, University of Brescia, Brescia (Italy); Tsuji, Kouichi [Graduate School of Engineering, Osaka City University, Osaka (Japan); Fernández-Ruiz, Ramón [Servicio Interdepartamental de Investigación (SIdI), Laboratorio de TXRF, Universidad Autónoma de Madrid, Madrid (Spain); Margui, Eva [Department of Chemistry, University of Girona, Girona (Spain); Streli, Christina [TU Wien, Atominstitut,Radiation Physics, Vienna (Austria); Pepponi, Giancarlo [Fondazione Bruno Kessler, Povo, Trento (Italy); Stosnach, Hagen [Bruker Nano GmbH, Berlin (Germany); Yamada, Takashi [Rigaku Corporation, Takatsuki, Osaka (Japan); Vandenabeele, Peter [Department of Archaeology, Ghent University, Ghent (Belgium); Maina, David M.; Gatari, Michael [Institute of Nuclear Science and Technology, University of Nairobi, Nairobi (Kenya); Shepherd, Keith D.; Towett, Erick K. [World Agroforestry Centre (ICRAF), Nairobi (Kenya); Bennun, Leonardo [Laboratorio de Física Aplicada, Departamento de Física, Universidad de Concepción (Chile); Custo, Graciela; Vasquez, Cristina [Gerencia Química, Laboratorio B025, Centro Atómico Constituyentes, San Martín (Argentina); Depero, Laura E., E-mail: laura.depero@unibs.it [Chemistry for Technologies Laboratory, University of Brescia, Brescia (Italy)

    2014-11-01

    Total Reflection X-Ray Fluorescence (TXRF) is a mature technique to evaluate quantitatively the elemental composition of liquid samples deposited on clean and well polished reflectors. In this paper the results of the first worldwide TXRF round-robin test of water samples, involving 18 laboratories in 10 countries are presented and discussed. The test was performed within the framework of the VAMAS project, interlaboratory comparison of TXRF spectroscopy for environmental analysis, whose aim is to develop guidelines and a standard methodology for biological and environmental analysis by means of the TXRF analytical technique. - Highlights: • The discussion of the first worldwide TXRF round-robin test of water samples (18 laboratories of 10 countries) is reported. • Drinking, waste, and desalinated water samples were tested. • Data dispersion sources were identified: sample concentration, preparation, fitting procedure, and quantification. • The protocol for TXRF analysis of drinking water is proposed.

  15. Power and sample size calculation for paired recurrent events data based on robust nonparametric tests.

    Science.gov (United States)

    Su, Pei-Fang; Chung, Chia-Hua; Wang, Yu-Wen; Chi, Yunchan; Chang, Ying-Ju

    2017-05-20

    The purpose of this paper is to develop a formula for calculating the required sample size for paired recurrent events data. The developed formula is based on robust non-parametric tests for comparing the marginal mean function of events between paired samples. This calculation can accommodate the associations among a sequence of paired recurrent event times with a specification of correlated gamma frailty variables for a proportional intensity model. We evaluate the performance of the proposed method with comprehensive simulations including the impacts of paired correlations, homogeneous or nonhomogeneous processes, marginal hazard rates, censoring rate, accrual and follow-up times, as well as the sensitivity analysis for the assumption of the frailty distribution. The use of the formula is also demonstrated using a premature infant study from the neonatal intensive care unit of a tertiary center in southern Taiwan. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  16. Testing the Cuckoldry Risk Hypothesis of Partner Sexual Coercion in Community and Forensic Samples

    Directory of Open Access Journals (Sweden)

    Joseph A. Camilleri

    2009-04-01

    Full Text Available Evolutionary theory has informed the investigation of male sexual coercion but has seldom been applied to the analysis of sexual coercion within established couples. The cuckoldry risk hypothesis, that sexual coercion is a male tactic used to reduce the risk of extrapair paternity, was tested in two studies. In a community sample, indirect cues of infidelity predicted male propensity for sexual coaxing in the relationship, and direct cues predicted propensity for sexual coercion. In the forensic sample, we found that most partner rapists experienced cuckoldry risk prior to committing their offence and experienced more types of cuckoldry risk events than non-sexual partner assaulters. These findings suggest that cuckoldry risk influences male sexual coercion in established sexual relationships.

  17. [Respondent-Driven Sampling: a new sampling method to study visible and hidden populations].

    Science.gov (United States)

    Mantecón, Alejandro; Juan, Montse; Calafat, Amador; Becoña, Elisardo; Román, Encarna

    2008-01-01

    The paper introduces a variant of chain-referral sampling: respondent-driven sampling (RDS). This sampling method shows that methods based on network analysis can be combined with the statistical validity of standard probability sampling methods. In this sense, RDS appears to be a mathematical improvement of snowball sampling oriented to the study of hidden populations. However, we try to prove its validity with populations that are not within a sampling frame but can nonetheless be contacted without difficulty. The basics of RDS are explained through our research on young people (aged 14 to 25) who go clubbing, consume alcohol and other drugs, and have sex. Fieldwork was carried out between May and July 2007 in three Spanish regions: Baleares, Galicia and Comunidad Valenciana. The presentation of the study shows the utility of this type of sampling when the population is accessible but there is a difficulty deriving from the lack of a sampling frame. However, the sample obtained is not a random representative one in statistical terms of the target population. It must be acknowledged that the final sample is representative of a 'pseudo-population' that approximates to the target population but is not identical to it.

  18. Studies of heterogeneous samples and material composition by fluorescence XAFS

    Science.gov (United States)

    Tannazi, Firouzeh

    X-ray Absorption Fine Structure (XAFS) Spectroscopy has proven to be an important tool for studying the composition and structure of materials. One benefit of XAFS is that it can be applied to a wide variety of systems, including complex real-world samples such as those found in biology and the environment. Determination of the chemical speciation of toxic elements in the environment currently is an active area of research. This dissertation describes my application of XAFS to chemical speciation in environmental soil samples as well as synthetic samples. In situ experimental XAFS measurements of metal speciation in soil core samples were made and the results were correlated with speciation results from chemical extraction. Several numerical approaches were implemented and tested. A novel approach to determining speciation by a Linear Programming algorithm was developed and found to be the most successful method for dilute samples of small particle size, i.e. in the linear regime. However, discrepancies between the in situ speciation results and other methods led to a fundamental investigation of x-ray transport in heterogeneous samples in which the observed fluorescence spectrum no longer is a linear combination of the spectra of the constituents. Useful theoretical models of x-ray propagation through heterogeneous media were found in older x-ray spectrometry literature, corrected, adapted for the first time to XAFS spectra. A Monte Carlo method was developed to calculate the effect on spectra of the shape, size, and orientation of particles of arbitrary convex shape, and the results are parameterized so that the loss factors can be easily calculated. Combining these models permits one to compute the fluorescence from arbitrary randomly heterogeneous particulate samples. This work demonstrates that the particle size distribution and the solid packing fraction have an important effect on the resulting spectra, which, if neglected, can introduce significant errors

  19. Improved evaluation of measurement uncertainty from sampling by inclusion of between-sampler bias using sampling proficiency testing.

    Science.gov (United States)

    Ramsey, Michael H; Geelhoed, Bastiaan; Wood, Roger; Damant, Andrew P

    2011-04-07

    A realistic estimate of the uncertainty of a measurement result is essential for its reliable interpretation. Recent methods for such estimation include the contribution to uncertainty from the sampling process, but they only include the random and not the systematic effects. Sampling Proficiency Tests (SPTs) have been used previously to assess the performance of samplers, but the results can also be used to evaluate measurement uncertainty, including the systematic effects. A new SPT conducted on the determination of moisture in fresh butter is used to exemplify how SPT results can be used not only to score samplers but also to estimate uncertainty. The comparison between uncertainty evaluated within- and between-samplers is used to demonstrate that sampling bias is causing the estimates of expanded relative uncertainty to rise by over a factor of two (from 0.39% to 0.87%) in this case. General criteria are given for the experimental design and the sampling target that are required to apply this approach to measurements on any material. © The Royal Society of Chemistry 2011

  20. Principles of Work Sample Testing. 1. A Non-Empirical Taxonomy of Test Uses

    Science.gov (United States)

    1979-04-01

    psychometric theory comes fram latent trait theoy (Iord, 1952), or latent structure anal- ysis ( Lazarsfeld , 1950), which attempts to identify item...Winston, 1962. Guion, R. M. Personnel testing. New York: McGraw-Hill, 1965. Lazarsfeld , P. F. 1he logical and mathematical foundation of latent structure

  1. Do Research Findings Apply to My Students? Examining Study Samples and Sampling

    Science.gov (United States)

    Cook, Bryan G.; Cook, Lysandra

    2017-01-01

    Special educators are urged to use research findings to inform their instruction in order to improve student outcomes. However, it can be difficult to tell whether and how research findings apply to one's own students. In this article, we discuss how special educators can consider the samples and the sampling methods in studies to examine the…

  2. A modified suspension test for estimating the mutagenicity of samples containing free and (or) protein-bound histidine.

    Science.gov (United States)

    Liu, Bo; Jin, Jianling; Cheng, Yanfei; Zhang, Huaiqiang; Gao, Peiji

    2009-02-01

    The Ames test has not been very effective in estimating the mutagenicity of histidine-containing samples because external free and (or) protein-bound histidine in these samples would allow the histidine auxotrophs in such test samples to grow more compared with the negative controls that were used as the reference. This could give rise to a false positive.n this study, a modified suspension mutagenicity assay (MS assay) was developed. The tester strains were incubated in Luria-Bertani (LB) broth containing different concentrations of traditional Chinese medicines (TCMs) until the declining phase, and the test samples were assayed to be mutagenic or not by observing whether statistically significant differences were demonstrated in the relative reversion frequencies (RRFs) between the negative control groups and the test groups. Collectively, using LB broth as the test medium and comparing the RRFs in the declining phase made this assay less influenced by the presence of histidine in the test samples.The mutagenicity of some TCMs was measured with the MS assay. The results in MS assay were consistent with those in the mammalian bone marrow chromosomal aberration test, which indicated that the MS assay was appropriate to estimate the mutagenicity of samples containing free and (or) protein-bound histidine.

  3. Dried Plasmodium falciparum-infected samples as positive controls for malaria rapid diagnostic tests

    Directory of Open Access Journals (Sweden)

    Aidoo Michael

    2012-07-01

    Full Text Available Abstract Background Rapid diagnostic tests (RDTs are central to fulfilling the WHO’s recommendation for parasitologic confirmation of all suspected cases of malaria. RDT performance may be compromised when exposed to the high temperature conditions typical of most malaria endemic regions. However, a systematic method to monitor RDT quality and performance in endemic countries is lacking at the present time. Current methods to monitor RDT performance in the field include comparing results from RDTs to diagnoses made by light microscopy and observing health workers perform tests. These methods are not substitutes for direct quality control. In this study, the suitability of dried Plasmodium falciparum-infected blood as quality control samples for malaria RDTs was evaluated. Methods Three cultured strains of P. falciparum at 200 and 2,000 parasites/μl were tested on 10 brands of RDT. After baseline testing to determine initial reactivity, aliquots of parasite-infected blood were air dried, stored at 35°C, room temperature (~25°C or 4°C for one, four and 12 weeks and were then tested on the 10 RDTs after rehydration. Extended stability testing of dried blood stored at 4°C was done using P. falciparum strain 3D7 at 1,000 and 2,000 parasites/μl. Results All dried blood samples at 2,000 parasites/μl retained reactivity (100% sensitivity at all three temperatures and time points for all nine RDT brands that detect histidine-rich protein-2 (HRP2. The dried blood samples with 200 parasites/μl were detected by six of the nine HRP2-based RDTs at all storage temperatures and time points. The sensitivity for two of the three remaining HRP2-based RDTs was 100% up to four weeks of storage at all temperatures but dropped to 87.5% at week 12. Of the four RDTs that detect plasmodium lactate dehydrogenase (pLDH in a pan-specific manner, alone or in combination with HRP2, the detection of pLDH in samples with 2,000 parasites/μL was 100% for two RDTs and

  4. Performance Evaluation of Commercial Dengue Diagnostic Tests for Early Detection of Dengue in Clinical Samples

    Directory of Open Access Journals (Sweden)

    Tuan Nur Akmalina Mat Jusoh

    2017-01-01

    Full Text Available The shattering rise in dengue virus infections globally has created a need for an accurate and validated rapid diagnostic test for this virus. Rapid diagnostic test (RDT and reverse transcription-polymerase chain reaction (RT-PCR diagnostic detection are useful tools for diagnosis of early dengue infection. We prospectively evaluated the diagnostic performance of nonstructural 1 (NS1 RDT and real-time RT-PCR diagnostic kits in 86 patient serum samples. Thirty-six samples were positive for dengue NS1 antigen while the remaining 50 were negative when tested with enzyme-linked immunosorbent assay (ELISA. Commercially available RDTs for NS1 detection, RTK ProDetect™, and SD Bioline showed high sensitivity of 94% and 89%, respectively, compared with ELISA. GenoAmp® Trioplex Real-Time RT-PCR and RealStar® Dengue RT-PCR tests presented a comparable kappa agreement with 0.722. The result obtained from GenoAmp® Real-Time RT-PCR Dengue test showed that 14 samples harbored dengue virus type 1 (DENV-1, 8 samples harbored DENV-2, 2 samples harbored DENV-3, and 1 sample harbored DENV-4. 1 sample had a double infection with DENV-1 and DENV-2. The NS1 RDTs and real-time RT-PCR tests were found to be a useful diagnostic for early and rapid diagnosis of acute dengue and an excellent surveillance tool in our battle against dengue.

  5. Sample size of the reference sample in a case-augmented study.

    Science.gov (United States)

    Ghosh, Palash; Dewanji, Anup

    2017-05-01

    The case-augmented study, in which a case sample is augmented with a reference (random) sample from the source population with only covariates information known, is becoming popular in different areas of applied science such as pharmacovigilance, ecology, and econometrics. In general, the case sample is available from some source (for example, hospital database, case registry, etc.); however, the reference sample is required to be drawn from the corresponding source population. The required minimum size of the reference sample is an important issue in this regard. In this work, we address the minimum sample size calculation and discuss related issues. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  6. Effects of fecal sampling on preanalytical and analytical phases in quantitative fecal immunochemical tests for hemoglobin.

    Science.gov (United States)

    Rapi, Stefano; Berardi, Margherita; Cellai, Filippo; Ciattini, Samuele; Chelazzi, Laura; Ognibene, Agostino; Rubeca, Tiziana

    2017-07-24

    Information on preanalytical variability is mandatory to bring laboratories up to ISO 15189 requirements. Fecal sampling is greatly affected by lack of harmonization in laboratory medicine. The aims of this study were to obtain information on the devices used for fecal sampling and to explore the effect of different amounts of feces on the results from the fecal immunochemical test for hemoglobin (FIT-Hb). Four commercial sample collection devices for quantitative FIT-Hb measurements were investigated. The volume of interest (VOI) of the probes was measured from diameter and geometry. Quantitative measurements of the mass of feces were carried out by gravimetry. The effects of an increased amount of feces on the analytical environment were investigated measuring the Hb values with a single analytical method. VOI was 8.22, 7.1 and 9.44 mm3 for probes that collected a target of 10 mg of feces, and 3.08 mm3 for one probe that targeted 2 mg of feces. The ratio between recovered and target amounts of devices ranged from 56% to 121%. Different changes in the measured Hb values were observed, in adding increasing amounts of feces in commercial buffers. The amounts of collected materials are related to the design of probes. Three out 4 manufacturers declare the same target amount using different sampling volumes and obtaining different amounts of collected materials. The introduction of a standard probes to reduce preanalytical variability could be an useful step for fecal test harmonization and to fulfill the ISO 15189 requirements.

  7. Comparative infectious serology testing of pre- and post-mortem blood samples from cornea donors.

    Science.gov (United States)

    Wilkemeyer, I; Pruss, A; Kalus, U; Schroeter, J

    2012-08-01

    Defined serological blood tests of deceased cornea donors are required to minimize the risk of viral infections of a transplant recipient as much as possible. Haemolysis, autolysis and bacterial contamination, may produce significant changes of post-mortem blood samples, which may lead to false serological test results. Pre- and post-mortem findings from the same cornea donors of the University Tissue Bank of the Charité in the years 2004-2009 (n = 487) were retrospectively analyzed and compared. The test results from pre-mortem blood samples were defined as the reference for the post-mortem blood test. Of 487 cornea donors, there were a total of 21 cases (4.3%) with discrepancies between serological test results from pre- and post-mortem blood samples. Of these, 7 values referred to the HBsAg-testing, 3 to the anti-HBs-, 1 to the anti-HBcIgG + IgM-, 1 to the anti-HCV-, 4 to the anti-HIV 1/2- and 5 to the TPLA-findings. False negative results within post-mortem serology occurred in 4 of 487 cases (0.8%). False positive results within the post-mortem blood samples occurred at a much more frequent rate, with 17 of 487 cases (3.5%). Discrepancies between serological pre- and post-mortem blood tests occur mainly due to the use of non-validated test systems. Therefore, it seems reasonable to test pre- and post-mortem blood samples serologically, whenever possible, at the same time, regardless of the sample age. Positive results, regardless of the sample type, should always be retested with validated confirmation tests (e.g. NAT), in order to differentiate between false and true positive results.

  8. Testing green coffee for ochratoxin A, part III: performance of ochratoxin A sampling plan.

    Science.gov (United States)

    Vargas, Eugenia A; Whitaker, Thomas B; Santos, Eliene A; Slate, Andrew B; Lima, Franisco B; Franca, Regina C A

    2006-01-01

    Green coffee shipments are often inspected for ochratoxin A (OTA) and classified into good or bad categories depending on whether the OTA estimates are above or below a defined regulatory limit. Because of the uncertainty associated with the sampling, sample preparation, and analytical steps of an OTA test procedure, some shipments of green coffee will be misclassified. The misclassification of lots leads to some good lots being rejected (sellers' risk) and some bad lots being accepted (buyers' risk) by an OTA sampling plan. Reducing the uncertainty of an OTA test procedure and using an accept/reject limit less than the regulatory limit can reduce the magnitude of one or both risks. The uncertainty of the OTA test procedure is most effectively reduced by increasing sample size (or increasing the number of samples analyzed), because the sampling step is the largest source of uncertainty in the OTA test procedure. The effects of increasing sample size and changing the sample accept/reject limit relative to the regulatory limit on the performance of OTA sampling plans for green coffee were investigated. For a given accept/reject limit of 5 microg/kg, increasing sample size increased the percentage of lots accepted at concentrations below the regulatory limit and increased the percentage of lots rejected at concentrations above the regulatory limit. As a result, increasing sample size reduced both the number of good lots rejected (sellers' risk) and the number of bad lots accepted (buyers' risk). For a given sample size (1 kg), decreasing the sample accept/reject limit from 5 to 2 microg/kg relative to a fixed regulatory limit of 5 microg/kg decreased the percentage of lots accepted and increased the percentage of lots rejected at all OTA concentrations. As a result, decreasing the accept/reject limit below the regulatory limit increased the number of good lots rejected (sellers' risk), but decreased the number of bad lots accepted (buyers' risk).

  9. HIV Testing in Urban Transgender Individuals: A Descriptive Study

    OpenAIRE

    Juarez-Cuellar, Adrian; Chang, Yu-Ping

    2017-01-01

    Abstract HIV testing is considered the initial component of HIV eradication strategies. This study aimed to describe HIV testing in urban, transgender individuals in western New York. The study uses HIV testing intake data from a sample of self-identified transgender males and females volunteering for an HIV test at a community-based healthcare organization. Transgender individuals with some characteristics were found to have more HIV tests including female gender, black, HIV status (positive...

  10. Second order analysis of two-stage rank tests for the one-sample problem

    NARCIS (Netherlands)

    Albers, Willem/Wim

    1991-01-01

    In this paper we present a rank analogue to Stein's two-stage procedure. We analyze its behavior to second order using existing asymptotic expansions for fixed sample size rank tests and recent results on combinations of independent rank statistics.

  11. 49 CFR 199.111 - Retention of samples and additional testing.

    Science.gov (United States)

    2010-10-01

    ... the employee according to DOT Procedures, the split specimen must be tested. The employee may specify... laboratory must follow approved chain-of-custody procedures in transferring a portion of the sample. (d...

  12. Mountain Braking Test Venue Study

    Science.gov (United States)

    2013-12-12

    FMVSS 105 Inertia Brake Dynamometer Test Procedure for vehicles above 4 540 kg GVWR; FMVSS Test Sequence, 2nd Fade Section,” November 2011.(15) Scope...Test Brake Temperature and Speed The U.S. Department of Defense Army Tank Purchase Description 2354A (ATPD-2354A) includes dynamometer test...11, March 1992. [12] "Performance Requirements for Determining Tow -Vehicle Gross Combination Weight Rating and Trailer Weight Rating", SAE Surface

  13. Suitability of Frozen Serum Stored in Gel Separator Primary Sampling Tubes for Serological Testing

    OpenAIRE

    Rosa-Fraile, Manuel; Sampedro, Antonio; Rodríguez-Granger, Javier; Camacho, Enrique; Manrique, Ester

    2004-01-01

    The suitability of frozen serum after storage in primary sampling tubes with a gel separator for serological enzyme-linked immunosorbent assay testing (hepatitis B virus surface antigen [HBs Ag], anti-HBs Ag, anti-Toxoplasma gondii immunoglobulin G [IgG], anti-rubella virus IgG, anti-cytomegalovirus IgM, and anti-Epstein-Barr virus IgM) was evaluated for 375 samples. No difference was found among test results using fresh or stored frozen serum

  14. 10 CFR Appendix A to Subpart U of... - Sampling Plan for Enforcement Testing of Electric Motors

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Sampling Plan for Enforcement Testing of Electric Motors A Appendix A to Subpart U of Part 431 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY... mean energy efficiency of the first sample (X 1) is equal to or greater than the lower control limit...

  15. 77 FR 58804 - Testing of Product Samples for Listeria monocytogenes: Changes in Procedures

    Science.gov (United States)

    2012-09-24

    ... Food Safety and Inspection Service Testing of Product Samples for Listeria monocytogenes: Changes in... Inspection Service (FSIS) is announcing changes in procedures for Listeria (L.) monocytogenes product... products for laboratory analysis (21 U.S.C. 642(a) and 460(b)). RTE Sampling Programs for Listeria...

  16. 19 CFR 151.68 - Merchandise to be sampled and tested by Customs.

    Science.gov (United States)

    2010-04-01

    ... wool or hair subject to duty at a rate per clean kilogram, except importations entered directly for....S.C. 1562) and dutiable after manipulation as wool or hair at a rate per clean kilogram; and (c... Hair § 151.68 Merchandise to be sampled and tested by Customs. The following shall be weighed, sampled...

  17. Probabilistic Requirements (Partial) Verification Methods Best Practices Improvement. Variables Acceptance Sampling Calculators: Empirical Testing. Volume 2

    Science.gov (United States)

    Johnson, Kenneth L.; White, K. Preston, Jr.

    2012-01-01

    The NASA Engineering and Safety Center was requested to improve on the Best Practices document produced for the NESC assessment, Verification of Probabilistic Requirements for the Constellation Program, by giving a recommended procedure for using acceptance sampling by variables techniques as an alternative to the potentially resource-intensive acceptance sampling by attributes method given in the document. In this paper, the results of empirical tests intended to assess the accuracy of acceptance sampling plan calculators implemented for six variable distributions are presented.

  18. Forensic Identification of Human Blood: comparison of two one-step presumptive tests for blood screening of crime scene samples.

    Directory of Open Access Journals (Sweden)

    Ana Flávia Belchior Andrade

    2014-08-01

    Full Text Available Blood is the most common body fluid found at crime scenes. One-step presumptive tests have been designed as a rapid immunological test for the qualitative detection of human hemoglobin in stool samples (faecal occult blood their usefulness for forensic purposes has been demonstrated before. In this study we compare Hexagon OBTI kit and FOB One-step Bioeasy kit sensitivity in the analysis of diluted blood samples. With Hexagon OBTI, positive test results are achieved in whole blood dilutions up to 1:1.000. Sensitivity decreased with aged samples, if samples were not stored under low temperatures regardless of which presumptive test is used. Whole blood tests must take into consideration that “hook” effect may interfere. Comparing both tests, OBTI Hexagon Kit is more sensible to detect diluted blood, showing a wider detection window in all conditions. This is interesting when analyzing forensic samples as forensic analysts usually do not know about the history of the analyzed sample before its collection.

  19. Predictive value of testing random urine sample to detect microalbuminuria in diabetic subjects during outpatient visit.

    Science.gov (United States)

    Bouhanick, B; Berrut, G; Chameau, A M; Hallar, M; Bled, F; Chevet, B; Vergely, J; Rohmer, V; Fressinaud, P; Marre, M

    1992-01-01

    The predictive value of random urine sample during outpatient visit to predict persistent microalbuminuria was studied in 76 Type 1, insulin-dependent diabetic subjects, 61 Type 2, non-insulin-dependent diabetic subjects, and 72 Type 2, insulin-treated diabetic subjects. Seventy-six patients attended outpatient clinic during morning, and 133 during afternoon. Microalbuminuria was suspected if Urinary Albumin Excretion (UAE) exceeded 20 mg/l. All patients were hospitalized within 6 months following outpatient visit, and persistent microalbuminuria was assessed then if UAE was between 30 and 300 mg/24 h on 2-3 occasions in 3 urines samples. Of these 209 subjects eighty-three were also screened with Microbumintest (Ames-Bayer), a semi-quantitative method. Among the 209 subjects, 71 were positive both for microalbuminuria during outpatient visit and a persistent microalbuminuria during hospitalization: sensitivity 91.0%, specificity 83.2%, concordance 86.1%, and positive predictive value 76.3% (chi-squared test: 191; p less than 10(-4)). Data were not different for subjects examined on morning, or on afternoon. Among the 83 subjects also screened with Microbumintest, 22 displayed both a positive reaction and a persistent microalbuminuria: sensitivity 76%, specificity 81%, concordance 80%, and positive predictive value 69% (chi-squared test: 126; p less than 10(-4)). Both types of screening appeared equally effective during outpatient visit. Hence, a persistent microalbuminuria can be predicted during an outpatient visit in a diabetic clinic.

  20. The outcome of dimethylglyoxime testing in a sample of cell phones in Denmark.

    Science.gov (United States)

    Thyssen, Jacob Pontoppidan; Johansen, Jeanne D; Zachariae, Claus; Menné, Torkil

    2008-07-01

    Nickel dermatitis may be caused by frequent and prolonged use of cell phones. Because little is known about the frequency of nickel release from cell phones, it is difficult to estimate the risk of nickel sensitization and dermatitis among their users. Inspired by a recent case of nickel dermatitis from prolonged cell phone use, the frequency of dimethylglyoxime (DMG)-positive cell phones on the Danish market was investigated. Five major cell phone companies were contacted. Two were visited, and the DMG test was performed on a sample of their products. 5 of 15 (33.3%) phones from company A and 3 of 26 (11.5%) phones from company B showed at least 1 positive reaction. 3 phones had more than 1 positive DMG spots. This study documents that excessive nickel release (i.e. a positive DMG test) is relatively frequent in a sample of cell phones from the Danish market. Prolonged use of cell phones may in some cases fulfil the criteria for items included in the European Union Nickel Directive. We believe that this new cause of nickel dermatitis should be carefully followed and that regulatory steps may be necessary.

  1. June 2012 Groundwater Sampling at the Central Nevada Test Area (Data Validation Package)

    Energy Technology Data Exchange (ETDEWEB)

    Findlay, Rick [S.M. Stoller Corporation, Broomfield, CO (United States)

    2013-03-01

    The U.S. Department of Energy Office of Legacy Management conducted annual sampling at the Central Nevada Test Area (CNTA) on June 26-27, 2012, in accordance with the 2004 Correction Action Decision Document/Corrective Action Plan for Corrective Action Unit 443: Central Nevada Test Area (CNTA)-Subsurface and the addendum to the "Corrective Action Decision Document/Corrective Action Plan" completed in 2008. Sampling and analysis were conducted as specified in the Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PLN/S04351), continually updated).

  2. Advances in paper-based sample pretreatment for point-of-care testing.

    Science.gov (United States)

    Tang, Rui Hua; Yang, Hui; Choi, Jane Ru; Gong, Yan; Feng, Shang Sheng; Pingguan-Murphy, Belinda; Huang, Qing Sheng; Shi, Jun Ling; Mei, Qi Bing; Xu, Feng

    2017-06-01

    In recent years, paper-based point-of-care testing (POCT) has been widely used in medical diagnostics, food safety and environmental monitoring. However, a high-cost, time-consuming and equipment-dependent sample pretreatment technique is generally required for raw sample processing, which are impractical for low-resource and disease-endemic areas. Therefore, there is an escalating demand for a cost-effective, simple and portable pretreatment technique, to be coupled with the commonly used paper-based assay (e.g. lateral flow assay) in POCT. In this review, we focus on the importance of using paper as a platform for sample pretreatment. We firstly discuss the beneficial use of paper for sample pretreatment, including sample collection and storage, separation, extraction, and concentration. We highlight the working principle and fabrication of each sample pretreatment device, the existing challenges and the future perspectives for developing paper-based sample pretreatment technique.

  3. Sample Size Calculation for Estimating or Testing a Nonzero Squared Multiple Correlation Coefficient

    Science.gov (United States)

    Krishnamoorthy, K.; Xia, Yanping

    2008-01-01

    The problems of hypothesis testing and interval estimation of the squared multiple correlation coefficient of a multivariate normal distribution are considered. It is shown that available one-sided tests are uniformly most powerful, and the one-sided confidence intervals are uniformly most accurate. An exact method of calculating sample size to…

  4. Power and Sample Size Calculations for Logistic Regression Tests for Differential Item Functioning

    Science.gov (United States)

    Li, Zhushan

    2014-01-01

    Logistic regression is a popular method for detecting uniform and nonuniform differential item functioning (DIF) effects. Theoretical formulas for the power and sample size calculations are derived for likelihood ratio tests and Wald tests based on the asymptotic distribution of the maximum likelihood estimators for the logistic regression model.…

  5. ELECTROCHEMICAL CORROSION TEST RESULTS FOR TANK 241-SY-102 SUPERNATE GRAB SAMPLES

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAN JB

    2007-04-09

    This report describes the electrochemical corrosion scans and conditions for testing of SY-102 supernatant samples taken December 2004. The testing was performed because the tank was under a Justification for Continued Operation allowing the supernatant composition to be outside the chemistry limits of Administrative Control 5.16, 'Corrosion Mitigation program'. A new electrochemical working electrode of A516 Grade 60 carbon steel was used for each scan; all scans were measured against a saturated calomel electrode, with carbon counter electrodes, and all scans were carried out at 50 C. The samples were scanned twice, once as received and once sparged with argon to deoxygenate the sample. For those scans conducted after argon purging, the corrosion rates ranged from 0.012 to 0.019 mpy. A test for stress corrosion cracking was carried out on one sample (2SY-04-07) with negative results.

  6. Self-Sampling for Human Papillomavirus Testing among Non-Attenders Increases Attendance to the Norwegian Cervical Cancer Screening Programme.

    Directory of Open Access Journals (Sweden)

    Espen Enerly

    Full Text Available Increasing attendance to screening offers the best potential for improving the effectiveness of well-established cervical cancer screening programs. Self-sampling at home for human papillomavirus (HPV testing as an alternative to a clinical sampling can be a useful policy to increase attendance. To determine whether self-sampling improves screening attendance for women who do not regularly attend the Norwegian Cervical Cancer Screening Programme (NCCSP, 800 women aged 25-69 years in the Oslo area who were due to receive a 2nd reminder to attend regular screening were randomly selected and invited to be part of the intervention group. Women in this group received one of two self-sampling devices, Evalyn Brush or Delphi Screener. To attend screening, women in the intervention group had the option of using the self-sampling device (self-sampling subgroup or visiting their physician for a cervical smear. Self-sampled specimens were split and analyzed for the presence of high-risk (hr HPV by the CLART® HPV2 test and the digene® Hybrid Capture (HC2 test. The control group consisted of 2593 women who received a 2nd reminder letter according to the current guidelines of the NCCSP. The attendance rates were 33.4% in the intervention group and 23.2% in the control group, with similar attendance rates for both self-sampling devices. Women in the self-sampling subgroup responded favorably to both self-sampling devices and cited not remembering receiving a call for screening as the most dominant reason for previous non-attendance. Thirty-two of 34 (94.1% hrHPV-positive women in the self-sampling subgroup attended follow-up. In conclusion, self-sampling increased attendance rates and was feasible and well received. This study lends further support to the proposal that self-sampling may be a valuable alternative for increasing cervical cancer screening coverage in Norway.

  7. A GMM-Based Test for Normal Disturbances of the Heckman Sample Selection Model

    Directory of Open Access Journals (Sweden)

    Michael Pfaffermayr

    2014-10-01

    Full Text Available The Heckman sample selection model relies on the assumption of normal and homoskedastic disturbances. However, before considering more general, alternative semiparametric models that do not need the normality assumption, it seems useful to test this assumption. Following Meijer and Wansbeek (2007, the present contribution derives a GMM-based pseudo-score LM test on whether the third and fourth moments of the disturbances of the outcome equation of the Heckman model conform to those implied by the truncated normal distribution. The test is easy to calculate and in Monte Carlo simulations it shows good performance for sample sizes of 1000 or larger.

  8. EPS-LASSO: Test for High-Dimensional Regression Under Extreme Phenotype Sampling of Continuous Traits.

    Science.gov (United States)

    Xu, Chao; Fang, Jian; Shen, Hui; Wang, Yu-Ping; Deng, Hong-Wen

    2018-01-25

    Extreme phenotype sampling (EPS) is a broadly-used design to identify candidate genetic factors contributing to the variation of quantitative traits. By enriching the signals in extreme phenotypic samples, EPS can boost the association power compared to random sampling. Most existing statistical methods for EPS examine the genetic factors individually, despite many quantitative traits have multiple genetic factors underlying their variation. It is desirable to model the joint effects of genetic factors, which may increase the power and identify novel quantitative trait loci under EPS. The joint analysis of genetic data in high-dimensional situations requires specialized techniques, e.g., the least absolute shrinkage and selection operator (LASSO). Although there are extensive research and application related to LASSO, the statistical inference and testing for the sparse model under EPS remain unknown. We propose a novel sparse model (EPS-LASSO) with hypothesis test for high-dimensional regression under EPS based on a decorrelated score function. The comprehensive simulation shows EPS-LASSO outperforms existing methods with stable type I error and FDR control. EPS-LASSO can provide a consistent power for both low- and high-dimensional situations compared with the other methods dealing with high-dimensional situations. The power of EPS-LASSO is close to other low-dimensional methods when the causal effect sizes are small and is superior when the effects are large. Applying EPS-LASSO to a transcriptome-wide gene expression study for obesity reveals 10 significant body mass index associated genes. Our results indicate that EPS-LASSO is an effective method for EPS data analysis, which can account for correlated predictors. The source code is available at https://github.com/xu1912/EPSLASSO. hdeng2@tulane.edu. Supplementary data are available at Bioinformatics online.

  9. Test Plan - Solids Accumulation Scouting Studies

    Energy Technology Data Exchange (ETDEWEB)

    Duignan, M. R.; Steeper, T. J.; Steimke, J. L.; Fowley, M. D.

    2012-05-10

    This plan documents the highlights of the Solids Accumulations Scouting Studies test; a project, from Washington River Protection Solutions (WRPS), that began on February 1, 2012. During the last 12 weeks considerable progress has been made to design and plan methods that will be used to estimate the concentration and distribution of heavy fissile solids in accumulated solids in the Hanford double-shell tank (DST) 241-AW-105 (AW-105), which is the primary goal of this task. This DST will be one of the several waste feed delivery staging tanks designated to feed the Pretreatment Facility (PTF) of the Waste Treatment and Immobilization Plant (WTP). Note that over the length of the waste feed delivery mission AW-105 is currently identified as having the most fill empty cycles of any DST feed tanks, which is the reason for modeling this particular tank. At SRNL an existing test facility, the Mixing Demonstration Tank, which will be modified for the present work, will use stainless steel particles in a simulant that represents Hanford waste to perform mock staging tanks transfers that will allow solids to accumulate in the tank heel. The concentration and location of the mock fissile particles will be measured in these scoping studies to produce information that will be used to better plan larger scaled tests. Included in these studies is a secondary goal of developing measurement methods to accomplish the primary goal. These methods will be evaluated for use in the larger scale experiments. Included in this plan are the several pretest activities that will validate the measurement techniques that are currently in various phases of construction. Aspects of each technique, e.g., particle separations, volume determinations, topographical mapping, and core sampling, have been tested in bench-top trials, as discussed herein, but the actual equipment to be employed during the full test will need evaluation after fabrication and integration into the test facility.

  10. Considerations in determining sample size for pilot studies.

    Science.gov (United States)

    Hertzog, Melody A

    2008-04-01

    There is little published guidance concerning how large a pilot study should be. General guidelines, for example using 10% of the sample required for a full study, may be inadequate for aims such as assessment of the adequacy of instrumentation or providing statistical estimates for a larger study. This article illustrates how confidence intervals constructed around a desired or anticipated value can help determine the sample size needed. Samples ranging in size from 10 to 40 per group are evaluated for their adequacy in providing estimates precise enough to meet a variety of possible aims. General sample size guidelines by type of aim are offered.

  11. Reliability of different methods used for forming of working samples in the laboratory for seed testing

    Directory of Open Access Journals (Sweden)

    Opra Branislava

    2000-01-01

    Full Text Available The testing of seed quality starts from the moment a sample is formed in a warehouse during processing or packaging of the seed. The seed sampling as the process of obtaining the working sample also assumes each step undertaken during its testing in the laboratory. With the aim of appropriate forming of a seed sample in the laboratory, the usage of seed divider is prescribed for large seeded species (such as seed the size of wheat or larger (ISTA Rules, 1999. The aim of this paper was the comparison of different methods used for obtaining the working samples of maize and wheat seeds using conical, soil and centrifugal dividers. The number of seed of added admixtures confirmed the reliability of working samples formation. To each maize sample (1000 g 10 seeds of the following admixtures were added: Zea mays L. (red pericarp, Hordeum vulgäre L., Triticum aestivum L., and Glycine max (L. Merr. Two methods were used for formation of maze seed working sample. To wheat samples (1000 g 10 seeds of each of the following species were added: Avena saliva (hulled seeds, Hordeum vulgäre L., Galium tricorne Stokes, and Polygonum lapatifolmm L. For formation of wheat seed working samples four methods were used. Optimum of 9, but not less than 7 seeds of admixture were due to be determined in the maize seed working sample, while for wheat, at least one seed of admixture was expected to be found in the working sample. The obtained results confirmed that the formation of the maize seed working samples was the most reliable when centrifugal divider, the first method was used (average of admixture - 9.37. From the observed admixtures the seed of Triticum aestivum L. was the most uniformly distributed, the first method also being used (6.93. The second method gains high average values satisfying the given criterion, but it should be used with previous homogenization of the sample being tested. The forming of wheat seed working samples is the most reliable if the

  12. Relationships between Narrative Language Samples and Norm-Referenced Test Scores in Language Assessments of School-Age Children

    Science.gov (United States)

    Ebert, Kerry Danahy; Scott, Cheryl M.

    2014-01-01

    Purpose: Both narrative language samples and norm-referenced language tests can be important components of language assessment for school-age children. The present study explored the relationship between these 2 tools within a group of children referred for language assessment. Method: The study is a retrospective analysis of clinical records from…

  13. A simple nomogram for sample size for estimating sensitivity and specificity of medical tests

    Directory of Open Access Journals (Sweden)

    Malhotra Rajeev

    2010-01-01

    Full Text Available Sensitivity and specificity measure inherent validity of a diagnostic test against a gold standard. Researchers develop new diagnostic methods to reduce the cost, risk, invasiveness, and time. Adequate sample size is a must to precisely estimate the validity of a diagnostic test. In practice, researchers generally decide about the sample size arbitrarily either at their convenience, or from the previous literature. We have devised a simple nomogram that yields statistically valid sample size for anticipated sensitivity or anticipated specificity. MS Excel version 2007 was used to derive the values required to plot the nomogram using varying absolute precision, known prevalence of disease, and 95% confidence level using the formula already available in the literature. The nomogram plot was obtained by suitably arranging the lines and distances to conform to this formula. This nomogram could be easily used to determine the sample size for estimating the sensitivity or specificity of a diagnostic test with required precision and 95% confidence level. Sample size at 90% and 99% confidence level, respectively, can also be obtained by just multiplying 0.70 and 1.75 with the number obtained for the 95% confidence level. A nomogram instantly provides the required number of subjects by just moving the ruler and can be repeatedly used without redoing the calculations. This can also be applied for reverse calculations. This nomogram is not applicable for testing of the hypothesis set-up and is applicable only when both diagnostic test and gold standard results have a dichotomous category.

  14. Testing Short Samples of ITER Conductors and Projection of Their Performance in ITER Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Martovetsky, N N

    2007-08-20

    Qualification of the ITER conductor is absolutely necessary. Testing large scale conductors is expensive and time consuming. To test straight 3-4m long samples in a bore of a split solenoid is a relatively economical way in comparison with fabrication of a coil to be tested in a bore of a background field solenoid. However, testing short sample may give ambiguous results due to different constraints in current redistribution in the cable or other end effects which are not present in the large magnet. This paper discusses processes taking place in the ITER conductor, conditions when conductor performance could be distorted and possible signal processing to deduce behavior of ITER conductors in ITER magnets from the test data.

  15. Adaptive designs for the one-sample log-rank test.

    Science.gov (United States)

    Schmidt, Rene; Faldum, Andreas; Kwiecien, Robert

    2017-09-22

    Traditional designs in phase IIa cancer trials are single-arm designs with a binary outcome, for example, tumor response. In some settings, however, a time-to-event endpoint might appear more appropriate, particularly in the presence of loss to follow-up. Then the one-sample log-rank test might be the method of choice. It allows to compare the survival curve of the patients under treatment to a prespecified reference survival curve. The reference curve usually represents the expected survival under standard of the care. In this work, convergence of the one-sample log-rank statistic to Brownian motion is proven using Rebolledo's martingale central limit theorem while accounting for staggered entry times of the patients. On this basis, a confirmatory adaptive one-sample log-rank test is proposed where provision is made for data dependent sample size reassessment. The focus is to apply the inverse normal method. This is done in two different directions. The first strategy exploits the independent increments property of the one-sample log-rank statistic. The second strategy is based on the patient-wise separation principle. It is shown by simulation that the proposed adaptive test might help to rescue an underpowered trial and at the same time lowers the average sample number (ASN) under the null hypothesis as compared to a single-stage fixed sample design. © 2017, The International Biometric Society.

  16. Solubility testing of actinides on breathing-zone and area air samples

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, R.L.; Jessop, B.H.; McDowell, B.L. [Radiation Safety Engineering, Inc., Chandler, AZ (United States)

    1996-02-01

    A solubility testing method for several common actinides has been developed with sufficient sensitivity to allow profiles to be determined from routine breathing zone and area air samples in the workplace. Air samples are covered with a clean filter to form a filter-sample-filter sandwich which is immersed in an extracellular lung serum simulant solution. The sample is moved to a fresh beaker of the lung fluid simulant each day for one week, and then weekly until the end of the 28 day test period. The soak solutions are wet ashed with nitric acid and hydrogen peroxide to destroy the organic components of the lung simulant solution prior to extraction of the nuclides of interest directly into an extractive scintillator for subsequent counting on a Photon-Electron Rejecting Alpha Liquid Scintillation (PERALS{reg_sign}) spectrometer. Solvent extraction methods utilizing the extractive scintillators have been developed for the isotopes of uranium, plutonium, and curium. The procedures normally produce an isotopic recovery greater than 95% and have been used to develop solubility profiles from air samples with 40 pCi or less of U{sub 3}O{sub 8}. Profiles developed for U{sub 3}O{sub 8} samples show good agreement with in vitro and in vivo tests performed by other investigators on samples from the same uranium mills.

  17. Understanding and comparisons of different sampling approaches for the Fourier Amplitudes Sensitivity Test (FAST).

    Science.gov (United States)

    Xu, Chonggang; Gertner, George

    2011-01-01

    Fourier Amplitude Sensitivity Test (FAST) is one of the most popular uncertainty and sensitivity analysis techniques. It uses a periodic sampling approach and a Fourier transformation to decompose the variance of a model output into partial variances contributed by different model parameters. Until now, the FAST analysis is mainly confined to the estimation of partial variances contributed by the main effects of model parameters, but does not allow for those contributed by specific interactions among parameters. In this paper, we theoretically show that FAST analysis can be used to estimate partial variances contributed by both main effects and interaction effects of model parameters using different sampling approaches (i.e., traditional search-curve based sampling, simple random sampling and random balance design sampling). We also analytically calculate the potential errors and biases in the estimation of partial variances. Hypothesis tests are constructed to reduce the effect of sampling errors on the estimation of partial variances. Our results show that compared to simple random sampling and random balance design sampling, sensitivity indices (ratios of partial variances to variance of a specific model output) estimated by search-curve based sampling generally have higher precision but larger underestimations. Compared to simple random sampling, random balance design sampling generally provides higher estimation precision for partial variances contributed by the main effects of parameters. The theoretical derivation of partial variances contributed by higher-order interactions and the calculation of their corresponding estimation errors in different sampling schemes can help us better understand the FAST method and provide a fundamental basis for FAST applications and further improvements.

  18. QUALITY CONTROL TESTING OF VARIOUS SAMPLES OF PEPPERMINT OIL COLLECTED FROM LOCAL MARKET OF KARACHI, PAKISTAN

    National Research Council Canada - National Science Library

    Shaukat Khalid; Kaneez Fatima; Hina Yasin; Hira Naeem; Khan Usmanghani; Iqbal Ahmad

    2016-01-01

    .... In the present study, different samples of commercially available peppermint oil were subjected to standardization by determination of physicochemical characteristics, acid value, and resinified oil content...

  19. Detection of clarithromycin-resistant Helicobacter pylori by polymerase chain reaction using residual samples from rapid urease test

    Directory of Open Access Journals (Sweden)

    Jae-Sik Jeon

    2017-01-01

    Full Text Available Background: Approximately 50% of the world population is infected with Helicobacter pylori, which corresponds to a high infection rate. Furthermore, the incidence of antibiotic-resistant H. pylori has increased with the recent rise in use of antibiotics for H. pylori elimination, suggesting growing treatment failures. Aim: The study was aimed to assess the use of residual samples from rapid urease test (RUT for biomolecular testing as an effective and accurate method to detect antibiotic-resistant H. pylori. Settings and Design: This study was a retrospective study performed using data obtained from medical records of previously isolated H. pylori strains. Materials and Methods: RUT was conducted for 5440 biopsy samples from individuals who underwent health examination in South Korea. Subsequently, 469 RUT residual samples were randomly selected and subjected to polymerase chain reaction (PCR to detect antibiotic-resistant H. pylori. Statistical Analysis Used: The Chi-square test was used to analyse categorical data. P < 0.05 was considered statistically significant. Results: The results showed a concordance between the results of PCR and conventional RUT in 450 of 469 samples, suggesting that the H. pylori PCR test is a time- and cost-effective detection method. Conclusions: This study demonstrated that PCR test can aid physicians to prescribe the appropriate antibiotics at the time of diagnosis, thus preventing the reduction in H. pylori eradication due to antibiotic resistance, averting progression to serious diseases and increasing the treatment success rate.

  20. Planning Longitudinal Field Studies: Considerations in Determining Sample Size.

    Science.gov (United States)

    St.Pierre, Robert G.

    1980-01-01

    Factors that influence the sample size necessary for longitudinal evaluations include the nature of the evaluation questions, nature of available comparison groups, consistency of the treatment in different sites, effect size, attrition rate, significance level for statistical tests, and statistical power. (Author/GDC)

  1. Filtration and Leach Testing for PUREX Cladding Sludge and REDOX Cladding Sludge Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Shimskey, Rick W.; Billing, Justin M.; Buck, Edgar C.; Casella, Amanda J.; Crum, Jarrod V.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Hallen, Richard T.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Swoboda, Robert G.

    2009-03-02

    A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan (Barnes and Voke 2006). The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Hanford Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Under test plan TP RPP WTP 467 (Fiskum et al. 2007), eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. Under this test plan, a waste testing program was implemented that included: • Homogenizing the archive samples by group as defined in the test plan. • Characterizing the homogenized sample groups. • Performing parametric leaching testing on each group for compounds of interest. • Performing bench-top filtration/leaching tests in the hot cell for each group to simulate filtration and leaching activities if they occurred in the UFP2 vessel of the WTP Pretreatment Facility. This report focuses on a filtration/leaching test performed using two of the eight waste composite samples. The sample groups examined in this report were the plutonium-uranium extraction (PUREX) cladding waste sludge (Group 3, or CWP) and reduction-oxidation (REDOX) cladding waste sludge (Group 4, or CWR). Both the Group 3 and 4 waste composites were anticipated to be high in gibbsite, thus requiring caustic leaching. WTP RPT 167 (Snow et al. 2008) describes the homogenization, characterization, and parametric leaching activities before benchtop filtration/leaching testing of these two waste groups. Characterization and initial parametric data in that report were used to plan a single filtration/leaching test using a blend of both wastes. The test focused on filtration testing of the waste and caustic leaching for aluminum, in the form

  2. Comparison of Human Papillomavirus Detection in Urine and Cervical Samples Using High-Risk HPV DNA Testing in Northern Thailand

    OpenAIRE

    Surapan Khunamornpong; Jongkolnee Settakorn; Kornkanok Sukpan; Suree Lekawanvijit; Narisara Katruang; Sumalee Siriaunkgul

    2016-01-01

    Objective. To evaluate the performance of high-risk human papillomavirus (HPV) DNA testing in urine samples compared to that of cervical sample testing in Northern Thailand. Methods. Paired urine and cervical samples were collected during the follow-up of women with a previous positive HPV test. HPV testing was performed using the Cobas 4800 HPV Test. Linear Array assay was used for genotyping in selected cases. Results. Paired urine and cervical samples were obtained from 168 women. Of 123 p...

  3. Groundwater sampling in Olkiluoto, Eurajoki from borehole OL-KR6 during a long-term pumping test in 2005

    Energy Technology Data Exchange (ETDEWEB)

    Hirvonen, H. [Teollisuuden Voima Oy, Olkiluoto (Finland); Hatanpaeae, E. [Consulting Engineers Paavo Ristola Ltd, Hollola (Finland); Ahokas, H. [Poeyry Environment Oy, Vantaa (Finland)

    2006-12-15

    A long-term pumping test from borehole OL-KR6 in Olkiluoto was initiated in 2001. Since then, flow and in situ EC measurements, as well as groundwater sampling from specific sampling sections have been performed yearly. The aim of this study was to get information on the potential connections via fractures both to the sea and to deep saline groundwater during long-term pumping of the open borehole. In 2005 four groundwater samples were collected from four different sampling depths (98.5-100.5 m, 120-125 m, 135-137 m and 422-425 m) from borebole OL-KR6. The groundwater samples were taken from packed-off sections by means of PAVE equipment. The water types of groundwater samples from OL-KR6 were Na-Cl (for samples from 98.5-100.5 m and 135-137 m depths) and Na-Ca-Cl (for samples from 120-125 m and 422-425 m depths). The sample from depth 422-425 m was saline (TDS> 10000mg/L), while other waters were brackish (1000 mg < TDS <10000 mg/L). This study presents the sampling methods and the analysis results of groundwater samples from deep borehole OL-KR6. A comparison between the results of the in situ EC measurements and the EC results measured during groundwater sampling is presented. This report also contains a short comparison of the results obtained during the long-term pumping test during 2001-2005. (orig.)

  4. Characterization, Leaching, and Filtration Testing for Tributyl Phosphate (TBP, Group 7) Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Matthew K.; Billing, Justin M.; Blanchard, David L.; Buck, Edgar C.; Casella, Amanda J.; Casella, Andrew M.; Crum, J. V.; Daniel, Richard C.; Draper, Kathryn E.; Fiskum, Sandra K.; Jagoda, Lynette K.; Jenson, Evan D.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Shimskey, Rick W.; Snow, Lanee A.; Swoboda, Robert G.

    2009-03-09

    .A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. The actual waste-testing program included homogenizing the samples by group, characterizing the solids and aqueous phases, and performing parametric leaching tests. The tributyl phosphate sludge (TBP, Group 7) is the subject of this report. The Group 7 waste was anticipated to be high in phosphorus as well as aluminum in the form of gibbsite. Both are believed to exist in sufficient quantities in the Group 7 waste to address leaching behavior. Thus, the focus of the Group 7 testing was on the removal of both P and Al. The waste-type definition, archived sample conditions, homogenization activities, characterization (physical, chemical, radioisotope, and crystal habit), and caustic leaching behavior as functions of time, temperature, and hydroxide concentration are discussed in this report. Testing was conducted according to TP-RPP-WTP-467.

  5. Testing the DSM-5 severity indicator for bulimia nervosa in a treatment-seeking sample.

    Science.gov (United States)

    Dakanalis, Antonios; Clerici, Massimo; Riva, Giuseppe; Carrà, Giuseppe

    2017-03-01

    This study tested the new DSM-5 severity criterion for bulimia nervosa (BN) based on the frequency of inappropriate weight compensatory behaviors in a treatment-seeking sample. Participants were 345 adults with DSM-5 BN presenting for treatment. They were sub-grouped based on DSM-5 severity levels and compared on a range of variables of clinical interest and demographics. Based on DSM-5 severity definitions, 27.2 % of the sample was categorized with mild, 26.1 % with moderate, 24.9 % with severe, and 21.8 % with extreme severity of BN. Analyses revealed that the four (mild, moderate, severe, and extreme) severity groups of BN significantly differed from each other in eating disordered and body-related attitudes and behaviors, factors involved in the maintenance process of the disorder, comorbid psychiatric disorders, psychological distress, and psychosocial impairment (medium-to-large effect sizes). No significant between-group differences were observed in demographics, body mass index, or at the age when BN first occurred, lending some credence to recent suggestions that age-at-onset of BN may be more a disorder- than a severity-dependent variable. Collectively, our findings provide support for the severity indicator for BN introduced in the DSM-5 as a means of addressing heterogeneity and variability in the severity of the disorder.

  6. Five commercial DNA extraction systems tested and compared on a stool sample collection.

    Science.gov (United States)

    Persson, Søren; de Boer, Richard F; Kooistra-Smid, Anna M D; Olsen, Katharina E P

    2011-03-01

    In this study, 5 different commercial DNA extraction systems were tested on a stool sample collection containing 81 clinical stool specimens that were culture-positive for diarrheagenic Escherichia coli, Campylobacter jejuni, Salmonella enterica, or Clostridium difficile. The purified DNAs were analyzed by polymerase chain reaction (PCR) directed toward the relevant organisms. The results showed that conventional PCR combined with the extraction systems BioRobot EZ1 (Qiagen, Hilden, Germany), Bugs'n Beads (Genpoint, Oslo, Norway), ChargeSwitch (Invitrogen, Paisley, UK), QIAamp Stool Mini Kit (Qiagen), and 2 protocols (generic and Specific A) for EasyMag (BioMérieux, Marcy I'Etoile, France) were able to identify 89%, 62%, 85%, 88%, 85%, and 91%, respectively, of the pathogens originally identified by conventional culture-based methods. When TaqMan PCR was combined with the EasyMag Specific A protocol, 99% of the samples were correctly identified. The results demonstrate that the extraction efficiencies can vary significantly among different extraction systems, careful optimization may have a significant positive effect, and the use of sensitive and specific detection methods like TaqMan PCR is an ideal choice for this type of analysis. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Critical tests for determination of microbiological quality and biological activity in commercial vermicompost samples of different origins.

    Science.gov (United States)

    Grantina-Ievina, Lelde; Andersone, Una; Berkolde-Pīre, Dace; Nikolajeva, Vizma; Ievinsh, Gederts

    2013-12-01

    The aim of the present paper was to show that differences in biological activity among commercially produced vermicompost samples can be found by using a relatively simple test system consisting of microorganism tests on six microbiological media and soilless seedling growth tests with four vegetable crop species. Significant differences in biological properties among analyzed samples were evident both at the level of microbial load as well as plant growth-affecting activity. These differences were mostly manufacturer- and feedstock-associated, but also resulted from storage conditions of vermicompost samples. A mature vermicompost sample that was produced from sewage sludge still contained considerable number of Escherichia coli. Samples from all producers contained several potentially pathogenic fungal species such as Aspergillus fumigatus, Pseudallescheria boidii, Pseudallescheria fimeti, Pseudallescheria minutispora, Scedosporium apiospermum, Scedosporium prolificans, Scopulariopsis brevicaulis, Stachybotrys chartarum, Geotrichum spp., Aphanoascus terreus, and Doratomyces columnaris. In addition, samples from all producers contained plant growth-promoting fungi from the genera Trichoderma and Mortierella. The described system can be useful both for functional studies aiming at understanding of factors affecting quality characteristics of vermicompost preparations and for routine testing of microbiological quality and biological activity of organic waste-derived composts and vermicomposts.

  8. Acceptance sampling for attributes via hypothesis testing and the hypergeometric distribution

    Science.gov (United States)

    Samohyl, Robert Wayne

    2017-10-01

    This paper questions some aspects of attribute acceptance sampling in light of the original concepts of hypothesis testing from Neyman and Pearson (NP). Attribute acceptance sampling in industry, as developed by Dodge and Romig (DR), generally follows the international standards of ISO 2859, and similarly the Brazilian standards NBR 5425 to NBR 5427 and the United States Standards ANSI/ASQC Z1.4. The paper evaluates and extends the area of acceptance sampling in two directions. First, by suggesting the use of the hypergeometric distribution to calculate the parameters of sampling plans avoiding the unnecessary use of approximations such as the binomial or Poisson distributions. We show that, under usual conditions, discrepancies can be large. The conclusion is that the hypergeometric distribution, ubiquitously available in commonly used software, is more appropriate than other distributions for acceptance sampling. Second, and more importantly, we elaborate the theory of acceptance sampling in terms of hypothesis testing rigorously following the original concepts of NP. By offering a common theoretical structure, hypothesis testing from NP can produce a better understanding of applications even beyond the usual areas of industry and commerce such as public health and political polling. With the new procedures, both sample size and sample error can be reduced. What is unclear in traditional acceptance sampling is the necessity of linking the acceptable quality limit (AQL) exclusively to the producer and the lot quality percent defective (LTPD) exclusively to the consumer. In reality, the consumer should also be preoccupied with a value of AQL, as should the producer with LTPD. Furthermore, we can also question why type I error is always uniquely associated with the producer as producer risk, and likewise, the same question arises with consumer risk which is necessarily associated with type II error. The resolution of these questions is new to the literature. The

  9. Sampling Point Compliance Tests for 325 Building at Set-Back Flow Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ballinger, Marcel Y.; Glissmeyer, John A.; Barnett, J. Matthew; Recknagle, Kurtis P.; Yokuda, Satoru T.

    2011-05-31

    The stack sampling system at the 325 Building (Radiochemical Processing Laboratory [RPL]) was constructed to comply with the American National Standards Institute’s (ANSI’s) Guide to Sampling Airborne Radioactive Materials in Nuclear Facilities (ANSI N13.1-1969). This standard provided prescriptive criteria for the location of radionuclide air-sampling systems. In 1999, the standard was revised (Sampling and Monitoring Releases of Airborne Radioactive Substances From the Stacks and Ducts of Nuclear Facilities [ANSI/Health Physics Society [HPS] 13.1-1999]) to provide performance-based criteria for the location of sampling systems. Testing was conducted for the 325 Building stack to determine whether the sampling system would meet the updated criteria for uniform air velocity and contaminant concentration in the revised ANSI/HPS 13.1-1999 standard under normal operating conditions (Smith et al. 2010). Measurement results were within criteria for all tests. Additional testing and modeling was performed to determine whether the sampling system would meet criteria under set-back flow conditions. This included measurements taken from a scale model with one-third of the exhaust flow and computer modeling of the system with two-thirds of the exhaust flow. This report documents the results of the set-back flow condition measurements and modeling. Tests performed included flow angularity, uniformity of velocity, gas concentration, and particle concentration across the duct at the sampling location. Results are within ANSI/HPS 13.1-1999 criteria for all tests. These tests are applicable for the 325 Building stack under set-back exhaust flow operating conditions (980 - 45,400 cubic feet per minute [cfm]) with one fan running. The modeling results show that criteria are met for all tests using a two-fan configuration exhaust (flow modeled at 104,000 cfm). Combined with the results from the earlier normal operating conditions, the ANSI/HPS 13.1-1999 criteria for all tests

  10. You can pool faecal samples from individual pigs to test for Porcine Circovirus Type 2 and Lawsonia intracellularis using real-time PCRs

    DEFF Research Database (Denmark)

    Holyoake, Patricia K.; Hjulsager, Charlotte Kristiane; Larsen, Lars Erik

    Introduction Real-time PCR tests have been developed to detect and quantify Porcine Circovirus type 2 (PCV2) and Lawsonia intracellularis in pigs’ faeces. Pooling of individual faecal samples is often used to reduce the costs of diagnostic testing. The objective of this study was to evaluate any...... change in the test sensitivity of PCV2 and L. intracellularis real-time PCR when individual faecal samples were pooled. Materials and Methods Forty eight faecal samples were collected from the rectum of individual pigs (>10 weeks) from four farms. Faecal samples were classified as diarrhoea +/- based...... on subjective assessment of consistency. Three individual samples were combined to make 16 pooled samples (8 diarrhoea; 8 non-diarrhoea). Individual and pooled samples were tested using real-time PCR tests specific for PCV2 and L. intracellularis. A positive result in any of the three individual samples...

  11. Effects of test sample shape and surface production method on the fatigue behaviour of PMMA bone cement.

    Science.gov (United States)

    Sheafi, E M; Tanner, K E

    2014-01-01

    There is no consensus over the optimal criterion to define the fatigue life of bone cement in vitro. Fatigue testing samples have been made into various shapes using different surface preparation techniques with little attention being paid to the importance of these variations on the fatigue results. The present study focuses on the effect of test sample shape and surface production method on the fatigue results. The samples were manufactured with two cross sectional shapes: rectangular according to ISO 527 and circular according to ASTM F2118. Each shape was produced using two methods: direct moulding of the cement dough and machining from oversized rods. Testing was performed using two different bone cements: SmartSet GHV and DePuy CMW1. At least 10 samples of each category were tested, under fully reversed tension-compression fatigue stress at ±20MPa, to allow for Weibull analysis to compare results. The growth of fatigue cracks was observed by means of the changes in the absorbed energy and apparent modulus. It was found that fatigue crack growth can be altered by the sample shape and production method; however it is also dependent on the chemical composition of the cement. The results revealed that moulded samples, particularly those based on the ASTM F2118 standard, can lead to up to 5.5 times greater fatigue lives compared to the machined samples of the same cement. It is thus essential, when comparing the fatigue results of bone cement, to consider the effect of production method along with the shape of the test sample. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Characterization and Leach Testing for REDOX Sludge and S-Saltcake Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Fiskum, Sandra K.; Buck, Edgar C.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Hubler, Timothy L.; Jagoda, Lynette K.; Jenson, Evan D.; Kozelisky, Anne E.; Lumetta, Gregg J.; MacFarlan, Paul J.; McNamara, Bruce K.; Peterson, Reid A.; Sinkov, Sergey I.; Snow, Lanee A.; Swoboda, Robert G.

    2008-07-10

    This report describes processing and analysis results of boehmite waste type (Group 5) and insoluble high Cr waste type (Group 6). The sample selection, compositing, subdivision, physical and chemical characterization are described. Extensive batch leach testing was conducted to define kinetics and leach factors of selected analytes as functions of NaOH concentration and temperature. Testing supports issue M-12 resolution for the Waste Treatment Plant.

  13. Preference changes of adult outpatients for giving saliva, urine and blood for clinical testing after actual sample collection.

    Science.gov (United States)

    Dhima, Matilda; Salinas, Thomas J; Wermers, Robert A; Weaver, Amy L; Koka, Sreenivas

    2013-01-01

    Patients' preferences of the type of sample collections for clinical testing are currently unknown. The aims of this study were: (1) to assess patients' preferences of three types of samples for clinical testing (saliva, urine and blood) both before and after collection and (2) to assess whether prior experiences with collection of saliva impacted patients responses. Adult outpatients underwent collection of one sample each of saliva, urine and blood. Patients' perceptions of comfort, convenience and easiness were assessed in pre-collection and post-collection questionnaires. Post-collection, patients' endorsement of saliva as being the "most comfortable" and "most convenient" significantly declined (pre vs. post, 61.5% vs. 37.5% and 73.1% vs. 42.3%). However, saliva was still endorsed as the "most convenient" post-collection (compared to urine 33.7% and blood 24.0%). Although not statistically significant, the proportion of patients who changed their response in terms of what sample was "easiest to collect at home" was considerably higher in the group with vs. without prior experience giving saliva (54.6% vs. 32.6%, p=0.19 Fisher's exact test). Overall, saliva remained as the most highly preferred sample to donate despite a decline in patients' preferences of saliva donation after sample collection. The results of the study are promising for future widespread patient acceptance of saliva as a diagnostic fluid. Copyright © 2012 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  14. Development and initial evaluation of a lateral flow dipstick test for antigen detection of Entamoeba histolytica in stool sample.

    Science.gov (United States)

    Saidin, Syazwan; Yunus, Muhammad Hafiznur; Othman, Nurulhasanah; Lim, Yvonne Ai-Lian; Mohamed, Zeehaida; Zakaria, Nik Zairi; Noordin, Rahmah

    2017-05-01

    Entamoeba histolytica infection remains a public health concern in developing countries. Early diagnosis of amoebiasis can avoid disease complications, thus this study was aimed at developing a test that can rapidly detect the parasite antigens in stool samples. Rabbits were individually immunized with recombinant pyruvate phosphate dikinase (rPPDK) and E. histolytica excretory-secretory antigens to produce polyclonal antibodies. A rapid dipstick test was produced using anti-rPPDK PAb lined on the dipstick as capture reagent and anti-EhESA PAb conjugated to colloidal gold as the detector reagent. Using E. histolytica-spiked in stool sample of a healthy individual, the detection limit of the dipstick test was found to be 1000 cells ml -1 . Meanwhile when rPPDK was spiked in the stool sample, the minimum concentration detected by the dipstick test was 0.1 μg ml -1 . The performances of the dipstick, commercial Techlab E. histolytica II enzyme-linked immunosorbent assays (ELISA) and real-time PCR were compared using 70 stool samples from patients infected with Entamoeba species (n = 45) and other intestinal pathogens (n = 25). When compared to real-time PCR, the diagnostic sensitivity of the dipstick for detection of E. histolytica was 65.4% (n = 17/26); while the diagnostic specificity when tested with stool samples containing other intestinal pathogens was 92% (23/25). In contrast, Techlab E. histolytica II ELISA detected 19.2% (5/26) of the E. histolytica-positive samples as compared to real-time PCR. The lateral flow dipstick test produced in this study enabled rapid detection of E. histolytica, thus it showed good potential to be further developed into a diagnostic tool for intestinal amoebiasis.

  15. Astronaut Neil Armstrong studies rock samples during geological field trip

    Science.gov (United States)

    1969-01-01

    Astronaut Neil Armstrong, commander of the Apollo 11 lunar landing mission, studies rock samples during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas.

  16. Study of kissing molars in Turkish population sample | Yanik ...

    African Journals Online (AJOL)

    Study of kissing molars in Turkish population sample. ... refers to contacting occlusal surfaces of the impacted mandibular second and third molars. ... was to report the incidence of kissing molars (KMs), classification, incorporated pathologies, ...

  17. Use of PCR on lymph-node sample as test of cure of visceral leishmaniasis

    NARCIS (Netherlands)

    Osman, O. F.; Kager, P. A.; Zijlstra, E. E.; El-Hassan, A. M.; Oskam, L.

    1997-01-01

    When the polymerase chain reaction (PCR) was used to test lymph-node aspirates from 35 patients from eastern Sudan, who had had visceral leishmaniasis but were believed cured, leishmanial DNA was detected in samples from 14 of the patients. There were no significant differences between the

  18. Acceptability of self-collected vaginal samples for HPV testing in an ...

    African Journals Online (AJOL)

    3: Geneva Foundation for Medical Education and Research, Geneva, Switzerland. †Contributed equally. Abstract. Objective: To evaluate the acceptability of self-collected vaginal samples for HPV testing in women living in rural and urban areas of Madagascar. Materials and methods: Participants were recruited in a health ...

  19. Acceptability of self-collected vaginal samples for HPV testing in an ...

    African Journals Online (AJOL)

    Objective: To evaluate the acceptability of self-collected vaginal samples for HPV testing in women living in rural and urban areas of Madagascar. Materials and methods: Participants were recruited in a health care center (urban group) and smaller affiliated dispensaries (rural group). They were invited to perform ...

  20. Testing of a Microfluidic Sampling System for High Temperature Electrochemical MC&A

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Candido [Argonne National Lab. (ANL), Argonne, IL (United States); Nichols, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-11-27

    This report describes the preliminary validation of a high-temperature microfluidic chip system for sampling of electrochemical process salt. Electroanalytical and spectroscopic techniques are attractive candidates for improvement through high-throughput sample analysis via miniaturization. Further, microfluidic chip systems are amenable to micro-scale chemical processing such as rapid, automated sample purification to improve sensor performance. The microfluidic chip was tested to determine the feasibility of the system for high temperature applications and conditions under which microfluidic systems can be used to generate salt droplets at process temperature to support development of material balance and control systems in a used fuel treatment facility. In FY13, the project focused on testing a quartz microchip device with molten salts at near process temperatures. The equipment was installed in glove box and tested up to 400°C using commercial thermal transfer fluids as the carrier phase. Preliminary tests were carried out with a low-melting halide salt to initially characterize the properties of this novel liquid-liquid system and to investigate the operating regimes for inducing droplet flow within candidate carrier fluids. Initial results show that the concept is viable for high temperature sampling but further development is required to optimize the system to operate with process relevant molten salts.

  1. Test Sample for the Spatially Resolved Quantification of Illicit Drugs on Fingerprints Using Imaging Mass Spectrometry

    NARCIS (Netherlands)

    Muramoto, S.; Forbes, T.P.; van Asten, A.C.; Gillen, G.

    2015-01-01

    A novel test sample for the spatially resolved quantification of illicit drugs on the surface of a fingerprint using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and desorption electrospray ionization mass spectrometry (DESI-MS) was demonstrated. Calibration curves relating the signal

  2. Characterization of Electron Microscopes with Binary Pseudo-random Multilayer Test Samples

    Energy Technology Data Exchange (ETDEWEB)

    V Yashchuk; R Conley; E Anderson; S Barber; N Bouet; W McKinney; P Takacs; D Voronov

    2011-12-31

    Verification of the reliability of metrology data from high quality X-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested [1] and [2] and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer [5]. Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi2/Si multilayer coating with pseudo-randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize X-ray microscopes. Corresponding work with X-ray microscopes is in progress.

  3. Characterization of electron microscopes with binary pseudo-random multilayer test samples

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, Valeriy V., E-mail: VVYashchuk@lbl.gov [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Conley, Raymond [NSLS-II, Brookhaven National Laboratory, Upton, NY 11973 (United States); Anderson, Erik H. [Center for X-ray Optics, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Barber, Samuel K. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Bouet, Nathalie [NSLS-II, Brookhaven National Laboratory, Upton, NY 11973 (United States); McKinney, Wayne R. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Takacs, Peter Z. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Voronov, Dmitriy L. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2011-09-01

    Verification of the reliability of metrology data from high quality X-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer [5]. Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi{sub 2}/Si multilayer coating with pseudo-randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize X-ray microscopes. Corresponding work with X-ray microscopes is in progress.

  4. Finite sample of the Durbin-Watson test against fractionally integrated disturbances

    OpenAIRE

    Kleiber, Christian; Krämer, Walter

    2004-01-01

    We consider the finite sample power of various tests against serial correlation in the disturbances of a linear regression when these disturbances follow a stationary long memory process. It emerges that the power depends on the form of the regressor matrix and that, for the Durbin-Watson test and many other tests that can be written as ratios of quadratic forms in the disturbances, the power can drop to zero for certain regressors. We also provide a means to detect this zero-power trap. Our ...

  5. Report on Testing to Expand the Rotary Mode Core Sampling Operating Envelope

    Energy Technology Data Exchange (ETDEWEB)

    BOGER, R.M.

    1999-12-13

    The Tank Waste Remediation System (TWRS) Characterization Equipment Group requested that the Numatec Hanford Corporation--Engineering Testing Laboratory (ETL) perform Rotary Mode Core Sampling (RMCS) Operating Envelope (OE) testing. This testing was based upon Witwer 1998a and was performed at different time periods between May and September 1998. The purpose of this testing was to raise the maximum down force limit for rotary mode core sampling as outlined in the current OE. If testing could show that a higher down force could be used while drilling into a concrete/pumice block simulant while still remaining below the 60 C limitation, then the current OE could be revised to include the new, higher, down force limit. Although the Test Plan discussed varying the purge flow rate and rotation rate to find ''optimal'' drilling conditions, the number of drill bits that could be destructively tested was limited. Testing was subsequently limited in scope such that only the down force would be varied while the purge flow rate and rotation rate were kept constant at 30 scfm and 55 rpm respectively. A second objective, which was not part of the original test plan, was added prior to testing. The Bit Improvement testing, mentioned previously, revealed that the drill bits tested in the OE testing were made of a slightly different metal matrix than the ones currently used. The older bits, a Longyear part number 100IVD/5 (/5 bit), had tungsten carbide mixed into the metal matrix that forms the cutting teeth. The currently used bits, Longyear part number 100IVD/8 (/8 bit), instead have tungsten metal in the matrix and no tungsten carbide. Rockwell C hardness testing showed that the /5 bit was significantly harder than the /8 bit, with values of /8 vs. 8, respectively. The change from the /5 bit to the /8 bit was made immediately after the previous OE testing in 1996 because of sparking concerns with the tungsten carbide in the /5 bit. This difference in

  6. ELIMINATION OF THE CHARACTERIZATION OF DWPF POUR STREAM SAMPLE AND THE GLASS FABRICATION AND TESTING OF THE DWPF SLUDGE BATCH QUALIFICATION SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Amoroso, J.; Peeler, D.; Edwards, T.

    2012-05-11

    contrast, the variability study has significantly added value to the DWPF's qualification strategy. The variability study has evolved to become the primary aspect of the DWPF's compliance strategy as it has been shown to be versatile and capable of adapting to the DWPF's various and diverse waste streams and blending strategies. The variability study, which aims to ensure durability requirements and the PCT and chemical composition correlations are valid for the compositional region to be processed at the DWPF, must continue to be performed. Due to the importance of the variability study and its place in the DWPF's qualification strategy, it will also be discussed in this report. An analysis of historical data and Production Records indicated that the recommendation of the Six Sigma team to eliminate all characterization of pour stream glass samples and the glass fabrication and PCT performed with the qualification glass does not compromise the DWPF's current compliance plan. Furthermore, the DWPF should continue to produce an acceptable waste form following the remaining elements of the Glass Product Control Program; regardless of a sludge-only or coupled operations strategy. If the DWPF does decide to eliminate the characterization of pour stream samples, pour stream samples should continue to be collected for archival reasons, which would allow testing to be performed should any issues arise or new repository test methods be developed.

  7. Local two-sample testing: a new tool for analysing high-dimensional astronomical data

    Science.gov (United States)

    Freeman, P. E.; Kim, I.; Lee, A. B.

    2017-11-01

    Modern surveys have provided the astronomical community with a flood of high-dimensional data, but analyses of these data often occur after their projection to lower dimensional spaces. In this work, we introduce a local two-sample hypothesis test framework that an analyst may directly apply to data in their native space. In this framework, the analyst defines two classes based on a response variable of interest (e.g. higher mass galaxies versus lower mass galaxies) and determines at arbitrary points in predictor space whether the local proportions of objects that belong to the two classes significantly differ from the global proportion. Our framework has a potential myriad of uses throughout astronomy; here, we demonstrate its efficacy by applying it to a sample of 2487 I-band-selected galaxies observed by the HST-ACS in four of the CANDELS programme fields. For each galaxy, we have seven morphological summary statistics along with an estimated stellar mass and star formation rate (SFR). We perform two studies: one in which we determine regions of the seven-dimensional space of morphological statistics where high-mass galaxies are significantly more numerous than low-mass galaxies, and vice versa, and another study where we use SFR in place of mass. We find that we are able to identify such regions, and show how high-mass/low-SFR regions are associated with concentrated and undisturbed galaxies, while galaxies in low-mass/high-SFR regions appear more extended and/or disturbed than their high-mass/low-SFR counterparts.

  8. Norm Block Sample Sizes: A Review of 17 Individually Administered Intelligence Tests

    Science.gov (United States)

    Norfolk, Philip A.; Farmer, Ryan L.; Floyd, Randy G.; Woods, Isaac L.; Hawkins, Haley K.; Irby, Sarah M.

    2015-01-01

    The representativeness, recency, and size of norm samples strongly influence the accuracy of inferences drawn from their scores. Inadequate norm samples may lead to inflated or deflated scores for individuals and poorer prediction of developmental and academic outcomes. The purpose of this study was to apply Kranzler and Floyd's method for…

  9. Multivariate generalizations of the Wald--Wolfowitz and Smirnov two-sample tests

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, J.H.; Rafsky, L.C.

    1979-01-01

    Multivariate generalizations of the Wald--Wolfowitz runs statistic and the Smirnov maximum deviation statistic for the two-sample problem are presented. They are based on the minimal spanning tree of the pooled sample points. Some null distribution results are derived and a simulation study of power is reported. 5 figures, 2 tables.

  10. Methods for flexible sample-size design in clinical trials: Likelihood, weighted, dual test, and promising zone approaches.

    Science.gov (United States)

    Shih, Weichung Joe; Li, Gang; Wang, Yining

    2016-03-01

    Sample size plays a crucial role in clinical trials. Flexible sample-size designs, as part of the more general category of adaptive designs that utilize interim data, have been a popular topic in recent years. In this paper, we give a comparative review of four related methods for such a design. The likelihood method uses the likelihood ratio test with an adjusted critical value. The weighted method adjusts the test statistic with given weights rather than the critical value. The dual test method requires both the likelihood ratio statistic and the weighted statistic to be greater than the unadjusted critical value. The promising zone approach uses the likelihood ratio statistic with the unadjusted value and other constraints. All four methods preserve the type-I error rate. In this paper we explore their properties and compare their relationships and merits. We show that the sample size rules for the dual test are in conflict with the rules of the promising zone approach. We delineate what is necessary to specify in the study protocol to ensure the validity of the statistical procedure and what can be kept implicit in the protocol so that more flexibility can be attained for confirmatory phase III trials in meeting regulatory requirements. We also prove that under mild conditions, the likelihood ratio test still preserves the type-I error rate when the actual sample size is larger than the re-calculated one. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Correlates of sexually transmissible infection testing among a sample of at-risk young Australians.

    Science.gov (United States)

    Douglass, Caitlin H; Vella, Alyce M; Hellard, Margaret E; Lim, Megan S C

    2017-07-01

    Annual chlamydia testing is recommended for all sexually active Australians aged 15-29 years; however, the testing rate is below recommended levels. Three surveys at a Melbourne music festival were conducted over 2012-14 to identify correlates of sexually transmissible infection (STI) testing among young people at risk of STIs. In total, 3588 participants were recruited; 72% reported having sex in the past year. Based on sexual behaviours, 38% of sexually active participants were classified as at risk of contracting STIs. In the past year, at-risk participants had significantly higher odds of reporting a STI test (37%) than participants classified as not at risk (24%) (OR=1.9; CI=1.6-2.3). Among at-risk participants, correlates of STI testing in the past year included being aged 20-24 years, visiting a GP, higher knowledge levels, earlier sexual debut and reporting more than five lifetime partners. Testing rates in our sample did not meet levels required to reduce chlamydia prevalence. However, the testing rate was higher in at-risk participants than participants who were not at risk. Future programs aiming to increase chlamydia testing should improve knowledge and promote the importance of testing after risk exposure, particularly among 16- to 19-year-olds.

  12. Sample size and power calculation for molecular biology studies.

    Science.gov (United States)

    Jung, Sin-Ho

    2010-01-01

    Sample size calculation is a critical procedure when designing a new biological study. In this chapter, we consider molecular biology studies generating huge dimensional data. Microarray studies are typical examples, so that we state this chapter in terms of gene microarray data, but the discussed methods can be used for design and analysis of any molecular biology studies involving high-dimensional data. In this chapter, we discuss sample size calculation methods for molecular biology studies when the discovery of prognostic molecular markers is performed by accurately controlling false discovery rate (FDR) or family-wise error rate (FWER) in the final data analysis. We limit our discussion to the two-sample case.

  13. Doxycycline assay hair samples for testing long-term compliance treatment.

    Science.gov (United States)

    Angelakis, Emmanouil; Armstrong, Nicholas; Nappez, Claude; Richez, Magalie; Chabriere, Eric; Raoult, Didier

    2015-11-01

    Many patients undergoing long-term doxycycline treatment do not regularly take their treatment because of photosensitivity. Our objective was to create an assay for determining doxycycline levels and to use hair samples for monitoring the compliance over a longer period of time. We tested sera and hair samples from patients treated with doxycycline by a suitable ultra-high performance liquid chromatography (UHPLC) based assay. We estimated that the speed of hair growth is roughly 1.25 cm per month and we were able to determine doxycycline levels over a 6-month period. We tested 14 patients treated with doxycycline and we found similar levels of doxycycline in the serum and the hair samples representing the last 4 months. Linear regression analysis revealed that the level of doxycycline in the serum remained stable over time (p = 0.7) but the level of doxycycline in the hair decreased significantly over time (p = 0.03) indicating a degradation of this molecule in the hair. We detected two patients who did not have antibiotic in the hair, indicating a lack of compliance that was also confirmed by interview. Hair samples can be used to test long-term compliance in patients to explain failures or relapses. Copyright © 2015 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  14. Test of tree core sampling for screening of toxic elements in soils from a Norwegian site.

    Science.gov (United States)

    Algreen, Mette; Rein, Arno; Legind, Charlotte N; Amundsen, Carl Einar; Karlson, Ulrich Gosewinkel; Trapp, Stefan

    2012-04-01

    Tree core samples have been used to delineate organic subsurface plumes. In 2009 and 2010, samples were taken at trees growing on a former dump site in Norway and analyzed for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and zinc (Zn). Concentrations in wood were in averages (dw) 30 mg/kg for Zn, 2 mg/kg for Cu, and wood samples from the polluted test site were compared to those derived from a reference site. For all except one case, mean concentrations from the test site were higher than those from the reference site, but the difference was small and not always significant. Differences between tree species were usually higher than differences between reference and test site. Furthermore, all these elements occur naturally, and Cu, Ni, and Zn are essential minerals. Thus, all trees will have a natural background of these elements, and the occurrence alone does not indicate soil pollution. For the interpretation of the results, a comparison to wood samples from an unpolluted reference site with same species and similar soil conditions is required. This makes the tree core screening method less reliable for heavy metals than, e.g., for chlorinated solvents.

  15. Virtual rough samples to test 3D nanometer-scale scanning electron microscopy stereo photogrammetry.

    Science.gov (United States)

    Villarrubia, J S; Tondare, V N; Vladár, A E

    2016-01-01

    The combination of scanning electron microscopy for high spatial resolution, images from multiple angles to provide 3D information, and commercially available stereo photogrammetry software for 3D reconstruction offers promise for nanometer-scale dimensional metrology in 3D. A method is described to test 3D photogrammetry software by the use of virtual samples-mathematical samples from which simulated images are made for use as inputs to the software under test. The virtual sample is constructed by wrapping a rough skin with any desired power spectral density around a smooth near-trapezoidal line with rounded top corners. Reconstruction is performed with images simulated from different angular viewpoints. The software's reconstructed 3D model is then compared to the known geometry of the virtual sample. Three commercial photogrammetry software packages were tested. Two of them produced results for line height and width that were within close to 1 nm of the correct values. All of the packages exhibited some difficulty in reconstructing details of the surface roughness.

  16. An examination of the factor structure of the Alcohol Use Disorders Identification Test in two high-risk samples.

    Science.gov (United States)

    Shields, Alan L; Guttmannova, Katarina; Caruso, John C

    2004-06-01

    The Alcohol Use Disorders Identification Test (AUDIT) was examined by employing confirmatory factor analytic techniques to data from two samples collected 1998-1999: college students (n = 465) and court-referred, substance use treatment outpatients (clinical sample; n = 135). Despite the fact that the AUDIT was originally designed as a three-factor measure (consumption, dependence, and consequences), previous studies have lent support to one- and two-factor models. The results of this study support a two-factor model (alcohol consumption and dependence/consequences) in both samples. As further evidence that the two-factor model is appropriate, a psychometric evaluation suggested that the AUDIT generated reliable scores in both groups when used as either a one- or two-factor measure, but not when three scores are derived in the student sample.

  17. Sampling Key Populations for HIV Surveillance: Results From Eight Cross-Sectional Studies Using Respondent-Driven Sampling and Venue-Based Snowball Sampling.

    Science.gov (United States)

    Rao, Amrita; Stahlman, Shauna; Hargreaves, James; Weir, Sharon; Edwards, Jessie; Kochelani, Duncan; Kochelani, Duncan; Mavimbela, Mpumelelo; Baral, Stefan

    2017-10-20

    In using regularly collected or existing surveillance data to characterize engagement in human immunodeficiency virus (HIV) services among marginalized populations, differences in sampling methods may produce different pictures of the target population and may therefore result in different priorities for response. The objective of this study was to use existing data to evaluate the sample distribution of eight studies of female sex workers (FSW) and men who have sex with men (MSM), who were recruited using different sampling approaches in two locations within Sub-Saharan Africa: Manzini, Swaziland and Yaoundé, Cameroon. MSM and FSW participants were recruited using either respondent-driven sampling (RDS) or venue-based snowball sampling. Recruitment took place between 2011 and 2016. Participants at each study site were administered a face-to-face survey to assess sociodemographics, along with the prevalence of self-reported HIV status, frequency of HIV testing, stigma, and other HIV-related characteristics. Crude and RDS-adjusted prevalence estimates were calculated. Crude prevalence estimates from the venue-based snowball samples were compared with the overlap of the RDS-adjusted prevalence estimates, between both FSW and MSM in Cameroon and Swaziland. RDS samples tended to be younger (MSM aged 18-21 years in Swaziland: 47.6% [139/310] in RDS vs 24.3% [42/173] in Snowball, in Cameroon: 47.9% [99/306] in RDS vs 20.1% [52/259] in Snowball; FSW aged 18-21 years in Swaziland 42.5% [82/325] in RDS vs 8.0% [20/249] in Snowball; in Cameroon 15.6% [75/576] in RDS vs 8.1% [25/306] in Snowball). They were less educated (MSM: primary school completed or less in Swaziland 42.6% [109/310] in RDS vs 4.0% [7/173] in Snowball, in Cameroon 46.2% [138/306] in RDS vs 14.3% [37/259] in Snowball; FSW: primary school completed or less in Swaziland 86.6% [281/325] in RDS vs 23.9% [59/247] in Snowball, in Cameroon 87.4% [520/576] in RDS vs 77.5% [238/307] in Snowball) than the snowball

  18. La comprehension du francais parle au niveau avance: un exemple de test (Comprehension of Spoken French at the Advanced Level: A Test Sample).

    Science.gov (United States)

    Mauriac, Paul

    1980-01-01

    The use of taped radio programs is suggested for testing advanced level French comprehension. In the testing technique described less attention is given to program content than to style and language usage. A sample test is presented. (MSE)

  19. A new inclinable shear apparatus for large sample testing: design and perspectives

    Science.gov (United States)

    Rickli, Ch.; Burger, S.; Herranhof, H.; Michel, T.; Moser, A.; Tröger, A.

    2012-04-01

    Soil bioengineering methods are commonly applied to protect slopes from erosion and shallow landslides. However, the precise effectiveness of vegetation regarding slope stability is difficult to determine. Root reinforcement can be evaluated directly in terms of the additional shear strength provided by roots in root-reinforced soils. In this context we designed a shearing device for large scale planted soil samples with the aim to provide information about the contribution of plant roots to soil shear strength. The apparatus allows investigations on soil block samples with roots of different plant species commonly used for remediation and habitat restoration purposes under almost natural conditions. Shear stress results of rooted soils can be compared to those of un-vegetated soils with similar soil types. New and different to conventionally applied concepts, shear tests can be performed at variable inclinations up to 45° , considering plant growth at the corresponding angle of slope. Furthermore, experiments can be conducted at variable depth of the shearing zone, with low normal stresses and low shearing rates of≥ 0.01 mm/min. The measurements involve shearing force, shearing displacement (up to 200 mm), normal stress, normal displacement (dilatancy/consolidation) all recorded with high accuracy. Saturated and partially saturated soil samples containing roots can be tested with the soil humidity measured near the shearing zone. An automatic data logging system was designed for real-time visualisation of the different parameters and recording all required data in conjunction with the described direct shear apparatus. The device for soil samples of up to 500 x 500 x 400 mm offers a unique possibility to span the gap between investigations concerning vegetation effects on small planted soil specimens (e.g. triaxial tests) and the calculation of slope stability on entire slopes with vegetation. In addition, it combines the advantages of laboratory tests under

  20. Development and Testing of Harpoon-Based Approaches for Collecting Comet Samples

    Science.gov (United States)

    Purves, Lloyd (Compiler); Nuth, Joseph (Compiler); Amatucci, Edward (Compiler); Wegel, Donald; Smith, Walter; Church, Joseph; Leary, James; Kee, Lake; Hill, Stuart; Grebenstein, Markus; hide

    2017-01-01

    Comets, having bright tails visible to the unassisted human eye, are considered to have been known about since pre-historic times. In fact 3,000-year old written records of comet sightings have been identified. In comparison, asteroids, being so dim that telescopes are required for observation, were not discovered until 1801. Yet, despite their later discovery, a space mission returned the first samples of an asteroid in 2010 and two more asteroid sample return missions have already been launched. By contrast no comet sample return mission has ever been funded, despite the fact that comets in certain ways are far more scientifically interesting than asteroids. Why is this? The basic answer is the greater difficulty, and consequently higher cost, of a comet sample return mission. Comets typically are in highly elliptical heliocentric orbits which require much more time and propulsion for Space Craft (SC) to reach from Earth and then return to Earth as compared to many asteroids which are in Earth-like orbits. It is also harder for a SC to maneuver safely near a comet given the generally longer communications distances and the challenge of navigating in the comet's, when the comet is close to perihelion, which turns out to be one of the most interesting times for a SC to get close to the comet surface. Due to the science value of better understanding the sublimation of volatiles near the comet surface, other contributions to higher cost as desire to get sample material from both the comet surface and a little below, to preserve the stratigraphy of the sample, and to return the sample in a storage state where it does not undergo undesirable alterations, such as aqueous. In response to these challenges of comet sample return missions, the NASA Goddard Space Flight Center (GFSC) has worked for about a decade (2006 to this time) to develop and test approaches for comet sample return that would enable such a mission to be scientifically valuable, while having acceptably

  1. A Two-Sample Test for Equality of Means in High Dimension.

    Science.gov (United States)

    Gregory, Karl Bruce; Carroll, Raymond J; Baladandayuthapani, Veerabhadran; Lahiri, Soumendra N

    2015-06-01

    We develop a test statistic for testing the equality of two population mean vectors in the "large-p-small-n" setting. Such a test must surmount the rank-deficiency of the sample covariance matrix, which breaks down the classic Hotelling T2 test. The proposed procedure, called the generalized component test, avoids full estimation of the covariance matrix by assuming that the p components admit a logical ordering such that the dependence between components is related to their displacement. The test is shown to be competitive with other recently developed methods under ARMA and long-range dependence structures and to achieve superior power for heavy-tailed data. The test does not assume equality of covariance matrices between the two populations, is robust to heteroscedasticity in the component variances, and requires very little computation time, which allows its use in settings with very large p. An analysis of mitochondrial calcium concentration in mouse cardiac muscles over time and of copy number variations in a glioblastoma multiforme data set from The Cancer Genome Atlas are carried out to illustrate the test.

  2. Serum Dried Samples to Detect Dengue Antibodies: A Field Study

    Directory of Open Access Journals (Sweden)

    Angelica Maldonado-Rodríguez

    2017-01-01

    Full Text Available Background. Dried blood and serum samples are useful resources for detecting antiviral antibodies. The conditions for elution of the sample need to be optimized for each disease. Dengue is a widespread disease in Mexico which requires continuous surveillance. In this study, we standardized and validated a protocol for the specific detection of dengue antibodies from dried serum spots (DSSs. Methods. Paired serum and DSS samples from 66 suspected cases of dengue were collected in a clinic in Veracruz, Mexico. Samples were sent to our laboratory, where the conditions for optimal elution of DSSs were established. The presence of anti-dengue antibodies was determined in the paired samples. Results. DSS elution conditions were standardized as follows: 1 h at 4°C in 200 µl of DNase-, RNase-, and protease-free PBS (1x. The optimal volume of DSS eluate to be used in the IgG assay was 40 µl. Sensitivity of 94%, specificity of 93.3%, and kappa concordance of 0.87 were obtained when comparing the antidengue reactivity between DSSs and serum samples. Conclusion. DSS samples are useful for detecting anti-dengue IgG antibodies in the field.

  3. Appearance Investment and Everyday Interpersonal Functioning: An Experience Sampling Study

    Science.gov (United States)

    Forand, Nicholas R.; Gunthert, Kathleen C.; German, Ramaris E.; Wenze, Susan J.

    2010-01-01

    Several studies have shown that body satisfaction affects interpersonal functioning. However, few have studied the specific interpersonal correlates of another important body image dimension, appearance investment--that is, the importance a woman places on appearance. We used an experience sampling design with PDA (personal digital assistant)…

  4. Sample Processor for Life on Icy Worlds (SPLIce): Design and Test Results

    Science.gov (United States)

    Chinn, Tori N.; Lee, Anthony K.; Boone, Travis D.; Tan, Ming X.; Chin, Matthew M.; McCutcheon, Griffin C.; Horne, Mera F.; Padgen, Michael R.; Blaich, Justin T.; Forgione, Joshua B.; hide

    2017-01-01

    We report the design, development, and testing of the Sample Processor for Life on Icy Worlds (SPLIce) system, a microfluidic sample processor to enable autonomous detection of signatures of life and measurements of habitability parameters in Ocean Worlds. This monolithic fluid processing-and-handling system (Figure 1; mass 0.5 kg) retrieves a 50-L-volume sample and prepares it to supply a suite of detection instruments, each with unique preparation needs. SPLIce has potential applications in orbiter missions that sample ocean plumes, such as found in Saturns icy moon Enceladus, or landed missions on the surface of icy satellites, such as Jupiters moon Europa. Answering the question Are we alone in the universe? is captivating and exceptionally challenging. Even general criteria that define life very broadly include a significant role for water [1,2]. Searches for extinct or extant life therefore prioritize locations of abundant water whether in ancient (Mars), or present (Europa and Enceladus) times. Only two previous planetary missions had onboard fluid processing: the Viking Biology Experiments [3] and Phoenixs Wet Chemistry Laboratory (WCL) [4]. SPLIce differs crucially from those systems, including its capability to process and distribute L-volume samples and the integration autonomous control of a wide range of fluidic functions, including: 1) retrieval of fluid samples from an evacuated sample chamber; 2) onboard multi-year storage of dehydrated reagents; 3) integrated pressure, pH, and conductivity measurement; 4) filtration and retention of insoluble particles for microscopy; 5) dilution or vacuum-driven concentration of samples to accommodate instrument working ranges; 6) removal of gas bubbles from sample aliquots; 7) unidirectional flow (check valves); 8) active flow-path selection (solenoid-actuated valves); 9) metered pumping in 100 nL volume increments. The SPLIce manifold, made of three thermally fused layers of precision-machined cyclo

  5. Microbiological evaluation of milk samples positive to California Mastitis Test in dairy buffalo cows (Buballus bubalis

    Directory of Open Access Journals (Sweden)

    D.J. Sturion

    2010-02-01

    Full Text Available In order to observe the microbiological status of CMT positive samples, 734 apparently health mammary quarters from buffalo cows were submitted to physical evaluation, strip cup test and CMT. After milk samples inoculation in 10% ovine blood agar base media and in MacConkey agar and incubation under aerobic condition for 72 hours at 37oC, identification was proceeded. According to CMT, 227 quarters (30,93% were positive, among them 73 (32,16% presented 1+ reaction, 53 (23,35% were 2+ and 101 (44,49% were 3+. Microbiological exams of such samples were positive in 147 (64,76% out of 227 CMT positive samples and among the remaining 72 (31,72% were negative and 8 (3,52 were contaminated. In the 147 microbiological positive samples 204 bacteria were found in pure or associated growth and the most frequent agents were: Corynebacterium sp (59,25%; Staphylococcus sp (17,65% among which 86,11% were coagulase negative and 13,89% were coagulase positive; and Micrococcus sp (6,37%. The results revealed that, excluding the eight contaminated samples, 147 (67,12% quarters out of 219 CMT positive could be considered as bacteria-carrier and that even in a smaller percentage false-positive results can cause problems in a sanitary program for mastitis control in dairy buffalo cows.

  6. Report on ignitability testing of flammable gasses in a core sampling drill string

    Energy Technology Data Exchange (ETDEWEB)

    Witwer, K.S., Westinghouse Hanford

    1996-12-01

    This document describes the results from testing performed at the Pittsburgh Research Center to determine the effects of an ignition of flammable gasses contained in a core sampling drill string. Testing showed that 1) An ignition of stoichiometric hydrogen and air in a vented 30 or 55 ft length of drill string will not force 28`` or more of water out the bottom of the drill string, and 2) An ignition of this same gas mixture will not rupture a vented or completely sealed drill string.

  7. Development of NASA's Sample Cartridge Assembly: Summary of GEDS Design, Development Testing, and Thermal Analyses

    Science.gov (United States)

    O'Connoer, Brian; Hernandez, Deborah; Hornsby, Linda; Brown, Maria; Horton-Mullins, Kathryn

    2017-01-01

    NASA's Sample Cartridge Assembly (SCA) project is responsible for designing and validating a payload that contains materials research samples in a sealed environment. The SCA will be heated in the European Space Agency's (ESA) Low Gradient Furnace (LGF) that is housed inside the Material Science Research Rack (MSRR) located on the International Space Station (ISS). The first Principle Investigator (PI) to utilize the SCA will focus on Gravitational Effects on Distortion in Sintering (GEDS) research. This paper will give a summary of the design and development test effort for the GEDS SCA and will discuss the role of thermal analysis in developing test profiles to meet the science and engineering requirements. Lessons learned will be reviewed and salient design features that may differ for each PI will be discussed.

  8. Confirmatory analysis of field-presumptive GSR test sample using SEM/EDS

    Science.gov (United States)

    Toal, Sarah J.; Niemeyer, Wayne D.; Conte, Sean; Montgomery, Daniel D.; Erikson, Gregory S.

    2014-09-01

    RedXDefense has developed an automated red-light/green-light field presumptive lead test using a sampling pad which can be subsequently processed in a Scanning Electron Microscope for GSR confirmation. The XCAT's sampling card is used to acquire a sample from a suspect's hands on the scene and give investigators an immediate presumptive as to the presence of lead possibly from primer residue. Positive results can be obtained after firing as little as one shot. The same sampling card can then be sent to a crime lab and processed on the SEM for GSR following ASTM E-1588-10 Standard Guide for Gunshot Residue Analysis by Scanning Electron Microscopy/Energy Dispersive X-Ray Spectrometry, in the same manner as the existing tape lifts currently used in the field. Detection of GSR-characteristic particles (fused lead, barium, and antimony) as small as 0.8 microns (0.5 micron resolution) has been achieved using a JEOL JSM-6480LV SEM equipped with an Oxford Instruments INCA EDS system with a 50mm2 SDD detector, 350X magnification, in low-vacuum mode and in high vacuum mode after coating with carbon in a sputter coater. GSR particles remain stable on the sampling pad for a minimum of two months after chemical exposure (long term stability tests are in progress). The presumptive result provided by the XCAT yields immediate actionable intelligence to law enforcement to facilitate their investigation, without compromising the confirmatory test necessary to further support the investigation and legal case.

  9. Evaluation of ELISA screening test for detecting aflatoxin in biogenic dust samples

    Energy Technology Data Exchange (ETDEWEB)

    Durant, J.T.

    1996-05-01

    Aflatoxin is a carcinogenic chemical that is sometimes produced when agricultural commodities are infested by the fungi Aspergillus flavus and A. Parasiticus. Aflatoxin has been found to be present in air samples taken around persons handling materials likely to be contaminated. The purpose of this investigation was to demonstrate the feasibility of using an Enzyme Linked Immunosorbent Assay (ELISA) test kit that was developed to screen for aflatoxin in bulk agricultural commodities, to an air sample. Samples were taken from two environments likely to be contaminated with aflatoxin, a dairy farm feed mixing operation and a peanut bagging operation. The dust collected from these environments was considered to be biogenic, in that it originated primarily from biological materials.

  10. Permutation tests in the two-sample problem for functional data

    OpenAIRE

    Cabaña, Alejandra; Estrada, Ana Maria; Peña, Jairo I.; Quiroz, Adolfo J.

    2016-01-01

    Three different permutation test schemes are discussed and compared in the context of the two-sample problem for functional data. One of the procedures was essentially introduced by Lopez-Pintado and Romo (2009), using notions of functional data depth to adapt the ideas originally proposed by Liu and Singh (1993) for multivariate data. Of the new methods introduced here, one is also based on functional data depths, but uses a different way (inspired by Meta-Analysis) to assess the significanc...

  11. Sample Results From The Extraction, Scrub, And Strip Test For The Blended NGS Solvent

    Energy Technology Data Exchange (ETDEWEB)

    Washington, A. L. II; Peters, T. B.

    2014-03-03

    This report summarizes the results of the extraction, scrub, and strip testing for the September 2013 sampling of the Next Generation Solvent (NGS) Blended solvent from the Modular Caustic Side-Solvent Extraction Unit (MCU) Solvent Hold Tank. MCU is in the process of transitioning from the BOBCalixC6 solvent to the NGS Blend solvent. As part of that transition, MCU has intentionally created a blended solvent to be processed using the Salt Batch program. This sample represents the first sample received from that blended solvent. There were two ESS tests performed where NGS blended solvent performance was assessed using either the Tank 21 material utilized in the Salt Batch 7 analyses or a simulant waste material used in the V-5/V-10 contactor testing. This report tabulates the temperature corrected cesium distribution, or DCs values, step recovery percentage, and actual temperatures recorded during the experiment. This report also identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. The calculated extraction DCs values using the Tank 21H material and simulant are 59.4 and 53.8, respectively. The DCs values for two scrub and three strip processes for the Tank 21 material are 4.58, 2.91, 0.00184, 0.0252, and 0.00575, respectively. The D-values for two scrub and three strip processes for the simulant are 3.47, 2.18, 0.00468, 0.00057, and 0.00572, respectively. These values are similar to previous measurements of Salt Batch 7 feed with lab-prepared blended solvent. These numbers are considered compatible to allow simulant testing to be completed in place of actual waste due to the limited availability of feed material.

  12. Understanding and comparisons of different sampling approaches for the Fourier Amplitudes Sensitivity Test (FAST)

    OpenAIRE

    Xu, Chonggang; Gertner, George

    2011-01-01

    Fourier Amplitude Sensitivity Test (FAST) is one of the most popular uncertainty and sensitivity analysis techniques. It uses a periodic sampling approach and a Fourier transformation to decompose the variance of a model output into partial variances contributed by different model parameters. Until now, the FAST analysis is mainly confined to the estimation of partial variances contributed by the main effects of model parameters, but does not allow for those contributed by specific interactio...

  13. Validation of the Cognition Test Battery for Spaceflight in a Sample of Highly Educated Adults.

    Science.gov (United States)

    Moore, Tyler M; Basner, Mathias; Nasrini, Jad; Hermosillo, Emanuel; Kabadi, Sushila; Roalf, David R; McGuire, Sarah; Ecker, Adrian J; Ruparel, Kosha; Port, Allison M; Jackson, Chad T; Dinges, David F; Gur, Ruben C

    2017-10-01

    Neuropsychological changes that may occur due to the environmental and psychological stressors of prolonged spaceflight motivated the development of the Cognition Test Battery. The battery was designed to assess multiple domains of neurocognitive functions linked to specific brain systems. Tests included in Cognition have been validated, but not in high-performing samples comparable to astronauts, which is an essential step toward ensuring their usefulness in long-duration space missions. We administered Cognition (on laptop and iPad) and the WinSCAT, counterbalanced for order and version, in a sample of 96 subjects (50% women; ages 25-56 yr) with at least a Master's degree in science, technology, engineering, or mathematics (STEM). We assessed the associations of age, sex, and administration device with neurocognitive performance, and compared the scores on the Cognition battery with those of WinSCAT. Confirmatory factor analysis compared the structure of the iPad and laptop administration methods using Wald tests. Age was associated with longer response times (mean β = 0.12) and less accurate (mean β = -0.12) performance, women had longer response times on psychomotor (β = 0.62), emotion recognition (β = 0.30), and visuo-spatial (β = 0.48) tasks, men outperformed women on matrix reasoning (β = -0.34), and performance on an iPad was generally faster (mean β = -0.55). The WinSCAT appeared heavily loaded with tasks requiring executive control, whereas Cognition assessed a larger variety of neurocognitive domains. Overall results supported the interpretation of Cognition scores as measuring their intended constructs in high performing astronaut analog samples.Moore TM, Basner M, Nasrini J, Hermosillo E, Kabadi S, Roalf DR, McGuire S, Ecker AJ, Ruparel K, Port AM, Jackson CT, Dinges DF, Gur RC. Validation of the Cognition Test Battery for spaceflight in a sample of highly educated adults. Aerosp Med Hum Perform. 2017; 88(10):937-946.

  14. Using meta-analysis for benefit transfer: In-sample convergent validity tests of an outdoor recreation database

    Science.gov (United States)

    Rosenberger, Randall S.; Loomis, John B.

    2000-04-01

    The application of metaregression analysis models for the purpose of benefit transfer is investigated using in-sample convergent validity tests on average value transfers. The database on which the metaregression analysis models are developed is composed of empirical outdoor recreation use value studies conducted from 1967 through 1998. Results of the convergent validity tests suggest that the national model is slightly more robust to changes in application than the Census Region models. The results suggest that the application of meta-analysis for benefit transfers is promising considering limitations imposed by inconsistent data reporting of original studies.

  15. Multiple sample setup for testing the hydrothermal stability of adsorbents in thermal energy storage applications

    Science.gov (United States)

    Fischer, Fabian; Laevemann, Eberhard

    2015-06-01

    Thermal energy storage based on adsorption and desorption of water on an adsorbent can achieve high energy storage densities. Many adsorbents lose adsorption capacity when operated under unfavourable hydrothermal conditions during adsorption and desorption. The stability of an adsorbent against stressing hydrothermal conditions is a key issue for its usability in adsorption thermal energy storage. We built an experimental setup that simultaneously controls the hydrothermal conditions of 16 samples arranged in a matrix of four temperatures and four water vapour pressures. This setup allows the testing of potential adsorbents between temperatures of 50 °C and 350 °C and water vapour pressures of up to 32 kPa. A measurement procedure that allows the detection of the hydrothermal stability of an adsorbent after defined time spans has been designed. We verified the functionality of the multiple sample measurements with a microporous adsorbent, a zeolite NaMSX. The hydrothermal stability of this zeolite is tested by water uptake measurements. A standard deviation lower than 1% of the 16 samples for detecting the hydrothermal stability enables setting different conditions in each sample cell. Further, we compared the water uptake measurements by measuring their adsorption isotherms with the volumetric device BELSORP Aqua 3 from Bel Japan.

  16. Report of testing and sampling of municipal supply well PM-4

    Energy Technology Data Exchange (ETDEWEB)

    Richard J. Koch; Patrick Longmire; David B. Rogers; Ken Mullen

    1999-12-01

    During drilling of regional aquifer characterization borehole R-25, located in the western part of Los Alamos National Laboratory (LANL) at Technical Area (TA) 16, groundwater samples were collected from perched zones of saturation and the regional aquifer that contained elevated levels of high explosive (HE) compounds. One of the nearest Los Alamos County municipal supply wells potentially located down gradient from borehole R-25 is PM-4, located on Mesita del Buey at the west end of TA-54. During the winter of 1998 and 1999 the pump in PM-4 had been removed from the well for scheduled maintenance by the Los Alamos County Public Utilities Department (PUD). Because the pump was removed from PM-4, the opportunity existed to enter the well to (1) perform tests to determine where within the regional aquifer groundwater entered the well and (2) collect groundwater samples from the producing zones for analyses to determine if HE contaminants were present in discrete zones within the regional aquifer. The report of the activities that were performed during March 1999 for the testing and sampling of municipal supply well PM-4 is provided. The report provides a description of the field activities associated with the two phases of the project, including (1) the results of the static and dynamic spinner log surveys, and (2) a description of the sampling activities and the field-measured groundwater quality parameters that were obtained during sampling activities. This report also provides the analytical results of the groundwater samples and a brief discussion of the results of the project.

  17. Evaluation of dengue NS1 antigen rapid tests and ELISA kits using clinical samples.

    Directory of Open Access Journals (Sweden)

    Subhamoy Pal

    Full Text Available Early diagnosis of dengue virus (DENV infection can improve clinical outcomes by ensuring close follow-up, initiating appropriate supportive therapies and raising awareness to the potential of hemorrhage or shock. Non-structural glycoprotein-1 (NS1 has proven to be a useful biomarker for early diagnosis of dengue. A number of rapid diagnostic tests (RDTs and enzyme-linked immunosorbent assays (ELISAs targeting NS1 antigen (Ag are now commercially available. Here we evaluated these tests using a well-characterized panel of clinical samples to determine their effectiveness for early diagnosis.Retrospective samples from South America were used to evaluate the following tests: (i "Dengue NS1 Ag STRIP" and (ii "Platelia Dengue NS1 Ag ELISA" (Bio-Rad, France, (iii "Dengue NS1 Detect Rapid Test (1st Generation" and (iv "DENV Detect NS1 ELISA" (InBios International, United States, (v "Panbio Dengue Early Rapid (1st generation" (vi "Panbio Dengue Early ELISA (2nd generation" and (vii "SD Bioline Dengue NS1 Ag Rapid Test" (Alere, United States. Overall, the sensitivity of the RDTs ranged from 71.9%-79.1% while the sensitivity of the ELISAs varied between 85.6-95.9%, using virus isolation as the reference method. Most tests had lower sensitivity for DENV-4 relative to the other three serotypes, were less sensitive in detecting secondary infections, and appeared to be most sensitive on Day 3-4 post symptom onset. The specificity of all evaluated tests ranged from 95%-100%.ELISAs had greater overall sensitivity than RDTs. In conjunction with other parameters, the performance data can help determine which dengue diagnostics should be used during the first few days of illness, when the patients are most likely to present to a clinic seeking care.

  18. Comparability of mineral oil testing for dry food and cardboard samples - Perspectives from different PT rounds.

    Science.gov (United States)

    Funk, Milena; Hillmann, Hedda; Derra, Ralph; Leist, Ulrich

    2017-11-14

    Mineral oil hydrocarbons (MOH) can be found in detectable levels in a multitude of foodstuffs. Therefore, chemical analysis of food for MOH gains importance. Different proficiency testing (PT) rounds on mineral oil testing have been performed in different matrices: cereals and rice as well as cardboard samples were examined. The laboratories participating in the PT rounds had to follow specific requirements for examination. The sample materials used contained different concentrations of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). The PT results were statistically evaluated according to ISO 13528:2005 and additionally the HorRat(R) value was calculated to gain information on the comparability of the mineral oil testing. It could be shown that for the examined sample materials and under the chosen specifications for testing a comparable determination of the mineral oil content is possible within the required relative standard deviations. A useful analytical determination can be achieved with an acceptable relative standard deviation of oil fractions at ≥1 mg/kg in food. In the concentration range for MOH in food of between 1 mg/kg and 2 mg/kg, relative standard deviations of 20-40% were achieved. MOH concentrations of ≥ 2 mg/kg food were determined with good relative standard deviations of around 20%. Moreover, due to the results gained within this work a statement concerning the comparability for MOSH and MOAH contents below concentrations of 1 mg/kg food is possible: under the chosen conditions for examination as part of this work, mineral oil determination below 1 mg/kg food showed high variability. To gain reliable information with regard to consumer protection on the risk of mineral oil contents in this low concentration range further standardisation of the test method is indicated.

  19. Comparative evaluation of commercially available point-of-care heartworm antigen tests using well-characterized canine plasma samples

    Directory of Open Access Journals (Sweden)

    Lindsay A. Starkey

    2017-11-01

    .0%]; SNAP® RT: sensitivity 90.9% [78.0–100.0%], specificity 98.8% [96.0–100.0%]. There were significant differences detected when comparing the sensitivities of the SNAP® RT and the Witness® HW to the DiroChek® among the 150 total samples (p = 0.003 and the 50 “borderline” samples (p = 0.001. Conclusions In this study, the sensitivity of the Witness® HW was higher than the sensitivity of the SNAP® RT when compared with the DiroChek® test results prior to heat treatment of samples.

  20. Testing an ionization chamber with gaseous samples and measurements of the (n, alpha) reaction cross sections

    CERN Document Server

    Gledenov, Yu M; Salatskii, V I; Sedyshev, P V; Andrzejewski, J; Szalanski, P

    1999-01-01

    A new ionization chamber with gaseous samples (GIC) has been designed and tested on the thermal and resonance neutron beams of FLNP's neutron sources. The exposed gas volume serves as a target for neutrons. The obtained thermal cross sections for the sup 1 sup 7 O(n, alpha) sup 1 sup 4 C, sup 2 sup 1 Ne(n, alpha) sup 1 sup 8 O and sup 3 sup 6 Ar(n, alpha) sup 3 sup 3 S reactions are (233+-12) mb, (0.18+-0.09) mb and (5.43+-0.27) mb, respectively. These measurements have been performed on a pure beam of thermal neutrons from the high flux reactor IBR-2; and they demonstrated high efficiency and reliability of the method. Compared to samples on substrates, the application of gaseous samples makes the beam background essentially lower, and what is more important, the background component is totally absent due to the absence of Li and B microimpurities in gaseous samples while they do present in the samples on substrates. The method is also applicable to measurements with resonance neutrons. The recovery capabili...

  1. Test of Fibre Bragg Gratings samples under High Fast Neutrons Fluence

    Science.gov (United States)

    Cheymol, G.; Remy, L.; Gusarov, A.; Kinet, D.; Mégret, P.; Laffont, G.; Blanchet, T.; Morana, A.; Marin, E.; Girard, S.

    2018-01-01

    Optical fibre sensors (OFS) are worthy of interest for measurements in nuclear reactor thanks to their unique features, particularly compact size and remote multi-point sensing for some of them. But besides non negligible constraints associated with the high temperature environment of the experiments of interest, it is well known that the performances of OFS can be severely affected by high level of radiations. The Radiation Induced Attenuation (RIA) in the fibre is probably most known effect, which can be to some extent circumvented by using rad hard fibres to limit the dynamic loss. However, when the fast neutron fluence reaches 1018 to 1019 n/cm2, the density and index variations associated to structural changes may deteriorate drastically the performances of OFS even if they are based on rad hard fibres, by causing direct errors in the measurements of temperature and/or strain changes. The aim of the present study is to access the effect of nuclear radiations on the Fabry Perot (FP) and of Fibre Bragg Grating (FBG) sensors through the comparison of measurements made on these OFS - or part of them - before and after irradiation [1]. In the context of development of OFS for high irradiation environment and especially for Material Testing Reactors (MTRs), Sake 2 experiment consists in an irradiation campaign at high level of gamma and neutron fluxes conducted on samples of fibre optics - bare or functionalised with FBG. The irradiation was performed at two levels of fast neutron fluence: 1 and 3.1019 n/cm2 (E>1MeV), at 250°± 25°C, in the SCK•CEN BR2 reactor (Mol Belgium). An irradiation capsule was designed to allow irradiation at the specified temperature without active control. The neutron fluence was measured with activation dosimeters and the results were compared with MCPN computations. Investigation of bare samples gives information on the density changes, while for the FBGs both density and refractive index perturbation are involved. Some results for

  2. Practical recommendations for population PK studies with sampling time errors.

    Science.gov (United States)

    Choi, Leena; Crainiceanu, Ciprian M; Caffo, Brian S

    2013-12-01

    Population pharmacokinetic (PK) data collected from routine clinical practice offers a rich source of valuable information. However, in observational population PK data, accurate time information for blood samples is often missing, resulting in measurement errors (ME) in the sampling time variable. The goal of this study was to investigate the effects on model parameters when a scheduled time is used instead of the actual blood sampling time, and to propose ME correction methods. Simulation studies were conducted based on two major factors: the curvature in PK profiles and the size of ME. As ME correction methods, transform both sides (TBS) models were developed with application of Box-Cox power transformation and Taylor expansion. The TBS models were compared to a conventional population PK model using simulations. The most important determinant of bias due to time ME was the degree of curvature (nonlinearity) in PK profiles; the smaller the curvature around sampling times, the smaller the associated bias. The second important determinant was the magnitude of ME; the larger the ME, the larger the bias. The proposed TBS models performed better than a conventional population PK modeling when curvature and ME were substantial. Time ME in sampling time can lead to bias on the parameter estimators. The following practical recommendations are provided: 1) when the curvature of PK profiles is small, conventional population PK modeling is robust to even large ME; and 2) when the curvature is moderate or large, the proposed methodology reduces bias in parameter estimates.

  3. Mars Sample Return and Flight Test of a Small Bimodal Nuclear Rocket and ISRU Plant

    Science.gov (United States)

    George, Jeffrey A.; Wolinsky, Jason J.; Bilyeu, Michael B.; Scott, John H.

    2014-01-01

    A combined Nuclear Thermal Rocket (NTR) flight test and Mars Sample Return mission (MSR) is explored as a means of "jump-starting" NTR development. Development of a small-scale engine with relevant fuel and performance could more affordably and quickly "pathfind" the way to larger scale engines. A flight test with subsequent inflight postirradiation evaluation may also be more affordable and expedient compared to ground testing and associated facilities and approvals. Mission trades and a reference scenario based upon a single expendable launch vehicle (ELV) are discussed. A novel "single stack" spacecraft/lander/ascent vehicle concept is described configured around a "top-mounted" downward firing NTR, reusable common tank, and "bottom-mount" bus, payload and landing gear. Requirements for a hypothetical NTR engine are described that would be capable of direct thermal propulsion with either hydrogen or methane propellant, and modest electrical power generation during cruise and Mars surface insitu resource utilization (ISRU) propellant production.

  4. The impact of screening-test negative samples not enumerated by MPN

    DEFF Research Database (Denmark)

    Corbellini, Luis Gustavo; Ribeiro Duarte, Ana Sofia; de Knegt, Leonardo

    2015-01-01

    In microbiological surveys, false negative results in detection tests precluding the enumeration by MPN may occur. The objective of this study was to illustrate the impact of screening test failure on the probability distribution of Salmonella concentrations in pork using a Bayesian method. A tot...

  5. The Stice model of overeating: Tests in clinical and non-clinical samples

    NARCIS (Netherlands)

    Strien, T. van; Engels, R.C.M.E.; Leeuwe, J.F.J. van; Snoek, H.M.

    2005-01-01

    The present study tested the dual pathway model of Stice [Stice, E (1994). A review of the evidence for a sociocultural model of bulimia nervosa and an exploration of the mechanisms of action. Clinical Psychology Review, 14, 633-661 and Stice, E. (2001). A prospective test of the dual-pathway model

  6. Astronauts Armstrong and Aldrin study rock samples during field trip

    Science.gov (United States)

    1969-01-01

    Astronaut Neil Armstrong, commander of the Apollo 11 lunar landing mission, and Astronaut Edwin Aldrin, Lunar module pilot for Apollo 11, study rock samples during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas.

  7. Genesis Solar Wind Collector Cleaning Assessment: 60366 Sample Case Study

    Science.gov (United States)

    Goreva, Y. S.; Gonzalez, C. P.; Kuhlman, K. R.; Burnett, D. S.; Woolum, D.; Jurewicz, A. J.; Allton, J. H.; Rodriguez, M. C.; Burkett, P. J.

    2014-01-01

    In order to recognize, localize, characterize and remove particle and thin film surface contamination, a small subset of Genesis mission collector fragments are being subjected to extensive study via various techniques [1-5]. Here we present preliminary results for sample 60336, a Czochralski silicon (Si-CZ) based wafer from the bulk array (B/C).

  8. Direct susceptibility testing by disk diffusion on clinical samples : a rapid and accurate tool for antibiotic stewardship

    NARCIS (Netherlands)

    Coorevits, L.; Boelens, J.; Claeys, G.

    We compared the accuracy of direct susceptibility testing (DST) with conventional antimicrobial susceptibility testing (AST), both using disk diffusion, on clinical samples. A total of 123 clinical samples (respiratory tract samples, urine, vaginal and abdominal abscess discharges, bile fluid and a

  9. 21 CFR 800.20 - Patient examination gloves and surgeons' gloves; sample plans and test method for leakage defects...

    Science.gov (United States)

    2010-04-01

    ...; sample plans and test method for leakage defects; adulteration. 800.20 Section 800.20 Food and Drugs FOOD... from the test method and sample plans in paragraphs (b) and (c) of this section. (2) For a description... Requirements for Specific Medical Devices § 800.20 Patient examination gloves and surgeons' gloves; sample...

  10. Analysis of fingerprint samples, testing various conditions, for forensic DNA identification.

    Science.gov (United States)

    Ostojic, Lana; Wurmbach, Elisa

    2017-01-01

    Fingerprints can be of tremendous value for forensic biology, since they can be collected from a wide variety of evident types, such as handles of weapons, tools collected in criminal cases, and objects with no apparent staining. DNA obtained from fingerprints varies greatly in quality and quantity, which ultimately affects the quality of the resulting STR profiles. Additional difficulties can arise when fingerprint samples show mixed STR profiles due to the handling of multiple persons. After applying a tested protocol for sample collection (swabbing with 5% Triton X-100), DNA extraction (using an enzyme that works at elevated temperatures), and PCR amplification (AmpFlSTR® Identifiler® using 31cycles) extensive analysis was performed to better understand the challenges inherent to fingerprint samples, with the ultimate goal of developing valuable profiles (≥50% complete). The impact of time on deposited fingerprints was investigated, revealing that while the quality of profiles deteriorated, full STR profiles could still be obtained from samples after 40days of storage at room temperature. By comparing the STR profiles from fingerprints of the dominant versus the non-dominant hand, we found a slightly better quality from the non-dominant hand, which was not always significant. Substrates seem to have greater effects on fingerprints. Tests on glass, plastic, paper and metal (US Quarter dollar, made of Cu and Ni), common substrates in offices and homes, showed best results for glass, followed by plastic and paper, while almost no profiles were obtained from a Quarter dollar. Important for forensic casework, we also assessed three-person mixtures of touched fingerprint samples. Unlike routinely used approaches for sampling evidence, the surface of an object (bottle) was sectioned into six equal parts and separate samples were taken from each section. The samples were processed separately for DNA extraction and STR amplification. The results included a few single

  11. Testing the applicability of six macroscopic skeletal aging techniques on a modern Southeast Asian sample.

    Science.gov (United States)

    Gocha, Timothy P; Ingvoldstad, Megan E; Kolatorowicz, Adam; Cosgriff-Hernandez, Meghan-Tomasita J; Sciulli, Paul W

    2015-04-01

    Most macroscopic skeletal aging techniques used by forensic anthropologists have been developed and tested only on reference material from western populations. This study examined the performance of six aging techniques on a known age sample of 88 Southeast Asian individuals. Methods examined included the Suchey-Brooks method of aging the symphyseal face of the os pubis (Brooks and Suchey, Hum. Evol. 5 (1990) 227), Buckberry and Chamberlain's, Am. J. Phys. Anthropol. 119 (2002) 231 and Osborne et al.'s, J. Forensic Sci. 49 (2004) 1 revisions of the Lovejoy et al., Am. J. Phys. Anthropol. 68 (1985) 15 method of aging the auricular surface of the ilium, İşcan et al.'s, J. Forensic Sci. 29 (1984) 1094, İşcan et al.'s, J. Forensic Sci. 30 (1985) 853 method of aging the sternal end of the fourth rib, and Meindl and Lovejoy's, Am. J. Phys. Anthropol. 68 (1985) 57 methods for aging both lateral-anterior and vault sutures on the cranium. The results of this study indicate that application of aging techniques commonly used in forensic anthropology to individuals identified as Asian, and more specifically Southeast Asian, should not be undertaken injudiciously. Of the six individual methods tested here, the Suchey-Brooks pubic symphysis aging method performs best, though average age estimates were still off by nearly 10 years or greater. Methods for aging the auricular surface perform next best, though the Osborne et al. method works better for individuals below 50 years and the Buckberry and Chamberlain method works better for those above 50 years. Methods for age estimation from the sternal ends of the fourth rib and vault and lateral-anterior cranial sutures perform poorly and are not recommended for use on remains of Southeast Asian ancestry. Combining age estimates from multiple indicators, specifically the pubic symphysis and one auricular surface method, was superior to individual methods. Data and a worked example are provided for calculating the conditional

  12. Sampling challenges in a study examining refugee resettlement

    Directory of Open Access Journals (Sweden)

    Thompson Sandra C

    2011-03-01

    Full Text Available Abstract Background As almost half of all refugees currently under United Nations protection are from Afghanistan or Iraq and significant numbers have already been resettled outside the region of origin, it is likely that future research will examine their resettlement needs. A number of methodological challenges confront researchers working with culturally and linguistically diverse groups; however, few detailed articles are available to inform other studies. The aim of this paper is to outline challenges with sampling and recruitment of socially invisible refugee groups, describing the method adopted for a mixed methods exploratory study assessing mental health, subjective wellbeing and resettlement perspectives of Afghan and Kurdish refugees living in New Zealand and Australia. Sampling strategies used in previous studies with similar refugee groups were considered before determining the approach to recruitment Methods A snowball approach was adopted for the study, with multiple entry points into the communities being used to choose as wide a range of people as possible to provide further contacts and reduce selection bias. Census data was used to assess the representativeness of the sample. Results A sample of 193 former refugee participants was recruited in Christchurch (n = 98 and Perth (n = 95, 47% were of Afghan and 53% Kurdish ethnicity. A good gender balance (males 52%, females 48% was achieved overall, mainly as a result of the sampling method used. Differences in the demographic composition of groups in each location were observed, especially in relation to the length of time spent in a refugee situation and time since arrival, reflecting variations in national humanitarian quota intakes. Although some measures were problematic, Census data comparison to assess reasonable representativeness of the study sample was generally reassuring. Conclusions Snowball sampling, with multiple initiation points to reduce selection bias, was

  13. Teacher-Student Relationship Inventory: Testing for Invariance across Upper Elementary and Junior High Samples

    Science.gov (United States)

    Ang, Rebecca P.; Chong, Wan Har; Huan, Vivien S.; Quek, Choon Lang; Yeo, Lay See

    2008-01-01

    Teacher-student relationships have been extensively studied in preschool and early elementary school samples. However, much less is known about children's relationships with their teachers in upper elementary grades through high school. Using confirmatory factor analysis, this study extended previous research by providing further evidence for the…

  14. Comparison of bacterial culture and qPCR testing of rectal and pen floor samples as diagnostic approaches to detect enterotoxic Escherichia coli in nursery pigs

    DEFF Research Database (Denmark)

    Weber, N. R.; Nielsen, J. P.; Hjulsager, Charlotte Kristiane

    2017-01-01

    : bacterial culturing of faecal samples from three pigs (per pen) with clinical diarrhoea and subsequent testing for virulence genes in E. coli isolates; bacterial culturing of pen floor samples and subsequent testing for virulence genes in E. coli isolates; qPCR testing of pen floor samples in order....... The only adhesin factor detected in this study was F18. When comparing bacterial culture or qPCR testing of pen floor samples with detection of ETEC-positive diarrhoeic pigs by culture, agreement was found in 26 (83.9%, Kappa = 0.665) and 23 (74.2%, Kappa = 0.488) of the pens, respectively. Agreement...... and qPCR. This study showed that both bacterial culture and qPCR testing of pen floor samples can be used as a diagnostic approach for detecting groups of ETEC-positive diarrhoeic nursery pigs....

  15. Sample size calculation based on exact test for assessing differential expression analysis in RNA-seq data.

    Science.gov (United States)

    Li, Chung-I; Su, Pei-Fang; Shyr, Yu

    2013-12-06

    Sample size calculation is an important issue in the experimental design of biomedical research. For RNA-seq experiments, the sample size calculation method based on the Poisson model has been proposed; however, when there are biological replicates, RNA-seq data could exhibit variation significantly greater than the mean (i.e. over-dispersion). The Poisson model cannot appropriately model the over-dispersion, and in such cases, the negative binomial model has been used as a natural extension of the Poisson model. Because the field currently lacks a sample size calculation method based on the negative binomial model for assessing differential expression analysis of RNA-seq data, we propose a method to calculate the sample size. We propose a sample size calculation method based on the exact test for assessing differential expression analysis of RNA-seq data. The proposed sample size calculation method is straightforward and not computationally intensive. Simulation studies to evaluate the performance of the proposed sample size method are presented; the results indicate our method works well, with achievement of desired power.

  16. Study of β-NMR for Liquid Biological Samples

    CERN Document Server

    Beattie, Caitlin

    2017-01-01

    β-NMR is an exotic form of NMR spectroscopy that allows for the characterization of matter based on the anisotropic β-decay of radioactive probe nuclei. This has been shown to be an effective spectroscopic technique for many different compounds, but its use for liquid biological samples is relatively unexplored. The work at the VITO line of ISOLDE seeks to employ this technique to study such samples. Currently, preparations are being made for an experiment to characterize DNA G-quadruplexes and their interactions with stabilizing cations. More specifically, the work in which I engaged as a summer student focused on the experiment’s liquid handling system and the stability of the relevant biological samples under vacuum.

  17. Self-sampling for human papillomavirus testing among rural young women of KwaZulu-Natal, South Africa.

    Science.gov (United States)

    Mbatha, J N; Galapaththi-Arachchige, H N; Mtshali, A; Taylor, M; Ndhlovu, P D; Kjetland, E F; Baay, M F D; Mkhize-Kwitshana, Z L

    2017-12-06

    Cervical cancer is a major problem in women and it is important to find a suitable and acceptable screening method, especially among young in low-resource areas for future human papillomavirus (HPV) vaccine follow-up investigations. The study sought to test the acceptability of self-sampling as well as the suitability of the specimen collecting devices. Ninety-eight young women from rural KwaZulu-Natal were enrolled between March and July 2014. Collected genital specimens were transferred to colour indicator cards for HPV detection. Participants answered a questionnaire where they described their experiences with self-sampling. Samples were tested for high-risk HPV using GP5/6+ PCR. Of the enrolled participants, 91 answered questionnaires and indicated that self-sampling was preferred by 51/91 (56%) women while 40/91 (44%) indicated preference for sampling by a doctor (p = 0.023). The majority, 64% were comfortable using a swab, 22% preferred a brush while 11% were comfortable with both devices. Of the 98 self-sampled specimens 61 were negative for HPV in both specimens while 37 were HPV-positive in either brush or swab. Of the 37, 26 (70%) were HPV-positive in both brush and swab (kappa = 0.743) and 11 (30%) were discordant. Self-sampling was acceptable to the majority of participants in this rural area. The Dacron swab was the preferred device, and can be used in combination with colour indicator cards for comfortable self-sampling, easy storage and transport of specimens plus detection.

  18. [Establishment of confirmatory test for suspicious hepatitis B surface antigen positive samples].

    Science.gov (United States)

    Chen, Lin; Rong, Yang; Liu, Jia; Xu, Jun; Guo, Jing-Xia; Song, Yong-Ji; Zhao, Jing; Liu, Ai-Xia; Yang, Li-Hua; Li, Bo-An; Mao, Yuan-Li

    2012-08-01

    Establish a confirmatory test based on ELISA, and use to verify the authenticity of HBsAg weak positive samples, pick and get rid of the false result, and avoid the mistake diagnosis. The particles (reagent A) coated by streptavidin and biotinylated HBsAb (reagent B) were mixed in different proportions, then neutralized with serum whose the COI of HBsAg > 20 by ELISA in order to identify the activity of HBsAb in confirmatory reagent. 30 pieces of HBsAg weak positive serum neutralized with the confirmatory reagent, the serum were considered to be positive if rate of decline of HBsAg COI > 50%. The results were compared to Roche confirmatory Kit. Confirmatory reagent was able to neutralized with HBsAg. 24 of 30 pieces of HBsAg weak positive samples were judged to be positive, while 6 poeces were negative. The ELISA comfirm method is fully consistent with Roche confirmatory Kit. The ELISA confirmatory test for suspicious HBsAg positive samples is a simple, accurate and low cost initial validation method, After further clinical trials, should be widely applied.

  19. Testing the sampling efficiency of a nuclear power station stack monitor

    Energy Technology Data Exchange (ETDEWEB)

    Stroem, L.H. [Instrumentinvest, Nykoeping (Sweden)

    1997-08-01

    The test method comprises the injection of known amounts of monodisperse particles in the stack air stream, at a suitable point upstream of the sampling installation. To find a suitable injection polls, the gas flow was mapped by means of a tracer gas, released in various points in the stack base. The resulting concentration distributions at the stack sampler level were observed by means of an array of gas detectors. An injection point that produced symmetrical distribution over the stack area, and low concentrations at the stack walls was selected for the particle tests. Monodisperse particles of 6, 10, and 19 {mu}m aerodynamic diameter, tagged with dysprosium, were dispersed in the selected injection point. Particle concentration at the sampler level was measured. The losses to the stack walls were found to be less than 10 %. The particle concentrations at the four sampler inlets were calculated from the observed gas distribution. The amount calculated to be aspirated into the sampler piping was compared with the quantity collected by the sampling train ordinary filter, to obtain the sampling line transmission efficiency. 1 ref., 2 figs.

  20. International round-robin study on the Ames fluctuation test.

    Science.gov (United States)

    Reifferscheid, G; Maes, H M; Allner, B; Badurova, J; Belkin, S; Bluhm, K; Brauer, F; Bressling, J; Domeneghetti, S; Elad, T; Flückiger-Isler, S; Grummt, H J; Gürtler, R; Hecht, A; Heringa, M B; Hollert, H; Huber, S; Kramer, M; Magdeburg, A; Ratte, H T; Sauerborn-Klobucar, R; Sokolowski, A; Soldan, P; Smital, T; Stalter, D; Venier, P; Ziemann, Chr; Zipperle, J; Buchinger, S

    2012-04-01

    An international round-robin study on the Ames fluctuation test [ISO 11350, 2012], a microplate version of the classic plate-incorporation method for the detection of mutagenicity in water, wastewater and chemicals was performed by 18 laboratories from seven countries. Such a round-robin study is a precondition for both the finalization of the ISO standardization process and a possible regulatory implementation in water legislation. The laboratories tested four water samples (spiked/nonspiked) and two chemical mixtures with and without supplementation of a S9-mix. Validity criteria (acceptable spontaneous and positive control-induced mutation counts) were fulfilled by 92-100%, depending on the test conditions. A two-step method for statistical evaluation of the test results is proposed and assessed in terms of specificity and sensitivity. The data were first subjected to powerful analysis of variance (ANOVA) after an arcsine-square-root transformation to detect significant differences between the test samples and the negative control (NC). A threshold (TH) value based on a pooled NC was then calculated to exclude false positive test results. Statistically, positive effects observed by the William's test were considered negative, if the mean of all replicates of a sample did not exceed the calculated TH. By making use of this approach, the overall test sensitivity was 100%, and the test specificity ranged from 80 to 100%. Copyright © 2012 Wiley Periodicals, Inc.

  1. Four-sample lactose hydrogen breath test for diagnosis of lactose malabsorption in irritable bowel syndrome patients with diarrhea.

    Science.gov (United States)

    Yang, Jian-Feng; Fox, Mark; Chu, Hua; Zheng, Xia; Long, Yan-Qin; Pohl, Daniel; Fried, Michael; Dai, Ning

    2015-06-28

    To validate 4-sample lactose hydrogen breath testing (4SLHBT) compared to standard 13-sample LHBT in the clinical setting. Irritable bowel syndrome patients with diarrhea (IBS-D) and healthy volunteers (HVs) were enrolled and received a 10 g, 20 g, or 40 g dose lactose hydrogen breath test (LHBT) in a randomized, double-blinded, controlled trial. The lactase gene promoter region was sequenced. Breath samples and symptoms were acquired at baseline and every 15 min for 3 h (13 measurements). The detection rates of lactose malabsorption (LM) and lactose intolerance (LI) for a 4SLHBT that acquired four measurements at 0, 90, 120, and 180 min from the same data set were compared with the results of standard LHBT. Sixty IBS-D patients and 60 HVs were studied. The genotype in all participants was C/C-13910. LM and LI detection rates increased with lactose dose from 10 g, 20 g to 40 g in both groups (P lactose doses in both groups. Reducing the number of measurements from 13 to 4 samples did not significantly impact on the accuracy of LHBT in health and IBS-D. 4SLHBT is a valid test for assessment of LM and LI in clinical practice.

  2. The Moral Competence Test: An Examination of Validity for Samples in the United States

    Science.gov (United States)

    Biggs, Donald A.; Colesante, Robert J.

    2015-01-01

    The Moral Competence Test (MCT) was designed over 30 years ago to provide a resource for educators interested in conducting cross-cultural studies of moral development and education. Since its origin, it has been translated into at least 30 languages and used in hundreds of studies. However, few studies provide evidence to support the use of the…

  3. Development of laser decontamination. 5. Decontamination test of the hot samples

    Energy Technology Data Exchange (ETDEWEB)

    Fukui, Yasutaka; Ogawa, Ryuichirou; Ishijima, Noboru; Tanimoto, Kenichi [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1999-08-01

    Process of laser decontamination system is as follows. As the material is irradiated by laser beam, its surface is instantaneously heated and ablated. Laser decontamination system is able to decontaminate thoroughly. In this work, the characteristics of laser beam transmission by optical fibers, and decontamination effect of laser beam irradiation to test pieces which are cut down of pipe in the hot facility, are experimented for apply laser decontamination technique to radioactive wastes treatment and decommissioning of nuclear fuel facilities. The results are as follows. (1) Beam transmission: Transmission of Q switch pulse YAG laser's beam by optical fibers are examined. Transmission energy is in proportion to incident energy to fiber. Transmission energy of bundled fiber is 168mJ to 406mJ of incident energy. In the case of incident energy was 425mJ, transmission energy was decrease, because some fibers of bundled fiber were damaged by laser beam. (2) Decontamination test of the hot samples: Counting rate of pipe test piece were decreased more than 90% by first irradiation of Q switch pulse YAG laser. Counting rate of pipe test piece were decreased no more than 4% by on and after second irradiation of Q switch pulse YAG laser. To move the test piece slowly, and to raise the density of irradiation energy, and to use the helium gas for auxiliary gas are effective to increase decontamination effect. (author)

  4. Further examination of embedded performance validity indicators for the Conners' Continuous Performance Test and Brief Test of Attention in a large outpatient clinical sample.

    Science.gov (United States)

    Sharland, Michael J; Waring, Stephen C; Johnson, Brian P; Taran, Allise M; Rusin, Travis A; Pattock, Andrew M; Palcher, Jeanette A

    2018-01-01

    Assessing test performance validity is a standard clinical practice and although studies have examined the utility of cognitive/memory measures, few have examined attention measures as indicators of performance validity beyond the Reliable Digit Span. The current study further investigates the classification probability of embedded Performance Validity Tests (PVTs) within the Brief Test of Attention (BTA) and the Conners' Continuous Performance Test (CPT-II), in a large clinical sample. This was a retrospective study of 615 patients consecutively referred for comprehensive outpatient neuropsychological evaluation. Non-credible performance was defined two ways: failure on one or more PVTs and failure on two or more PVTs. Classification probability of the BTA and CPT-II into non-credible groups was assessed. Sensitivity, specificity, positive predictive value, and negative predictive value were derived to identify clinically relevant cut-off scores. When using failure on two or more PVTs as the indicator for non-credible responding compared to failure on one or more PVTs, highest classification probability, or area under the curve (AUC), was achieved by the BTA (AUC = .87 vs. .79). CPT-II Omission, Commission, and Total Errors exhibited higher classification probability as well. Overall, these findings corroborate previous findings, extending them to a large clinical sample. BTA and CPT-II are useful embedded performance validity indicators within a clinical battery but should not be used in isolation without other performance validity indicators.

  5. Applicability of the Rey auditory-verbal learning test to an adult sample in Brazil.

    Science.gov (United States)

    Salgado, João Vinícius; Malloy-Diniz, Leandro Fernandes; Abrantes, Suzana Silva Costa; Moreira, Lafaiete; Schlottfeldt, Carlos Guilherme; Guimarães, Wanderlane; Freitas, Djeane Marcely Ugoline; Oliveira, Juliana; Fuentes, Daniel

    2011-09-01

    The Rey Auditory-Verbal Learning Test, which is used to evaluate learning and memory, is a widely recognized tool in the general literature on neuropsychology. This paper aims at presenting the performance of Brazilian adult subjects on the Rey Auditory-Verbal Learning Test, and was written after we published a previous study on the performance of Brazilian elderly subjects on this same test. A version of the test, featuring a list of high-frequency one-syllable and two-syllable concrete Portuguese substantives, was developed. Two hundred and forty-three (243) subjects from both genders were allocated to 6 different age groups (20-24; 25-29; 30-34; 35-44; 45-54 and 55-60 years old). They were then tested using the Rey Auditory-Verbal Learning Test. Performance on the Rey Auditory-Verbal Learning Test showed a positive correlation with educational level and a negative correlation with age. Women performed significantly better than men. When applied across similar age ranges, our results were similar to those recorded for the English version of the Rey Auditory-Verbal Learning Test. Our results suggest that the adaptation of the Rey Auditory-Verbal Learning Test to Brazilian Portuguese is appropriate and that it is applicable to Brazilian subjects for memory capacity evaluation purposes and across similar age groups and educational levels.

  6. EGFR mutation testing in lung cancer: a review of available methods and their use for analysis of tumour tissue and cytology samples.

    Science.gov (United States)

    Ellison, Gillian; Zhu, Guanshan; Moulis, Alexandros; Dearden, Simon; Speake, Georgina; McCormack, Rose

    2013-02-01

    Activating mutations in the gene encoding epidermal growth factor receptor (EGFR) can confer sensitivity to EGFR tyrosine kinase inhibitors such as gefitinib in patients with advanced non-small-cell lung cancer. Testing for mutations in EGFR is therefore an important step in the treatment-decision pathway. We reviewed reported methods for EGFR mutation testing in patients with lung cancer, initially focusing on studies involving standard tumour tissue samples. We also evaluated data on the use of cytology samples in order to determine their suitability for EGFR mutation analysis. We searched the MEDLINE database for studies reporting on EGFR mutation testing methods in patients with lung cancer. Various methods have been investigated as potential alternatives to the historical standard for EGFR mutation testing, direct DNA sequencing. Many of these are targeted methods that specifically detect the most common EGFR mutations. The development of targeted mutation testing methods and commercially available test kits has enabled sensitive, rapid and robust analysis of clinical samples. The use of screening methods, subsequent to sample micro dissection, has also ensured that identification of more rare, uncommon mutations is now feasible. Cytology samples including fine needle aspirate and pleural effusion can be used successfully to determine EGFR mutation status provided that sensitive testing methods are employed. Several different testing methods offer a more sensitive alternative to direct sequencing for the detection of common EGFR mutations. Evidence published to date suggests cytology samples are viable alternatives for mutation testing when tumour tissue samples are not available.

  7. Development and Testing of Harpoon-Based Approaches for Collecting Comet Samples (Video Supplement)

    Science.gov (United States)

    Purves, Lloyd (Compiler); Nuth, Joseph (Compiler); Amatucci, Edward (Compiler); Wegel, Donald; Smith, Walter; Leary, James; Kee, Lake; Hill, Stuart; Grebenstein, Markus; Voelk, Stefan; hide

    2017-01-01

    This video supplement contains a set of videos created during the approximately 10-year-long course of developing and testing the Goddard Space Flight Center (GSFC) harpoon-based approach for collecting comet samples. The purpose of the videos is to illustrate various design concepts used in this method of acquiring samples of comet material, the testing used to verify the concepts, and the evolution of designs and testing. To play the videos this PDF needs to be opened in the freeware Adobe Reader. They do not seem to play while within a browser. While this supplement can be used as a stand-alone document, it is intended to augment its parent document of the same title, Development and Testing of Harpoon-Based Approaches for Collecting Comet Samples (NASA/CR-2017-219018; this document is accessible from the website: https://ssed.gsfc.nasa.gov/harpoon/SAS_Paper-V1.pdf). The parent document, which only contains text and figures, describes the overall development and testing effort and contains references to each of the videos in this supplement. Thus, the videos are primarily intended to augment the information provided by the text and figures in the parent document. This approach was followed to allow the file size of the parent document to remain small enough to facilitate downloading and storage. Some of the videos were created by other organizations, Johns Hopkins University Applied Physics Laboratory (JHU APL) and the German Aerospace Center called, the Deutsches Zentrum für Luft- und Raumfahrt (DLR), who are partnering with GSFC on developing this technology. Each video is accompanied by text that provides a summary description of its nature and purpose, as well as the identity of the authors. All videos have been edited to only show key parts of the testing. Although not all videos have sound, the sound has been retained in those that have it. Also, each video has been given one or more title screens to clarify what is going in different phases of the video.

  8. Influence of Sample Size of Polymer Materials on Aging Characteristics in the Salt Fog Test

    Science.gov (United States)

    Otsubo, Masahisa; Anami, Naoya; Yamashita, Seiji; Honda, Chikahisa; Takenouchi, Osamu; Hashimoto, Yousuke

    Polymer insulators have been used in worldwide because of some superior properties; light weight, high mechanical strength, good hydrophobicity etc., as compared with porcelain insulators. In this paper, effect of sample size on the aging characteristics in the salt fog test is examined. Leakage current was measured by using 100 MHz AD board or 100 MHz digital oscilloscope and separated three components as conductive current, corona discharge current and dry band arc discharge current by using FFT and the current differential method newly proposed. Each component cumulative charge was estimated automatically by a personal computer. As the results, when the sample size increased under the same average applied electric field, the peak values of leakage current and each component current increased. Especially, the cumulative charges and the arc discharge length of dry band arc discharge increased remarkably with the increase of gap length.

  9. High acceptability of rapid HIV self-testing among a diverse sample of MSM from Buenos Aires, Argentina.

    Directory of Open Access Journals (Sweden)

    Maria A Pando

    Full Text Available The objective of this study was to explore the acceptability of rapid HIV self-testing (RHST among men who have sex with men (MSM.During 2006-2009, a sample of 500 MSM was recruited through Respondent Driven Sampling for an HIV prevalence/incidence study. Attitude toward RHST was explored among HIV negative MSM. Data were weighted prior to analyses.Participants reported they were likely to buy RHST (74%, test themselves more frequently than they currently do (77%, and that the procedure would simplify testing (70%. Furthermore, 71% reported they would probably use it alone, 66% would use it with a steady partner, and 56% with a friend/partner. While a majority acknowledged that RHST use would deprive them of receiving counseling (61%, 74% declared they would go for help if they tested positive; 57% would use an RHST in order to avoid condoms. Probability of use surpassed 70% among gay and non-gay identified MSM as well as those with and without a previous HIV test. Those likely to buy RHST were older (p = 0.025 and more likely to identify as gay (p = 0.036. A total of 17% said they would think about killing themselves and 9% would attempt suicide if they tested positive. These MSM were more likely to be younger (p<0.001, with lower mood level (p<0.001 and greater feelings of loneliness (p = 0.026.The high acceptability of RHST found among MSM should encourage the authorities to consider the possibility of offering it for self-testing, as it can improve early diagnosis and prevention of future transmissions. However, further research is needed to understand how to best disseminate RHST among MSM who wish to use it and to offer support and linkage to care for those who test HIV-positive.

  10. Controlled samples for silicon defect and impurity studies

    Energy Technology Data Exchange (ETDEWEB)

    Ciszek, T.F. [National Renewable Energy Lab., Golden, CO (United States)

    1995-08-01

    Because of the diverse defects and impurities that are present in any given sample of silicon material, it can be extremely difficult to conduct a controlled experiment to study the influence of any particular defect or impurity on photovoltaic properties such as minority charge carrier lifetime {tau} or solar cell efficiency q. For example, the influence of iron may be different if boron is present, or the influence of silicon self interstitial clusters may be different if oxygen is present. It thus becomes important to conduct such studies on controlled samples where the influence of secondary effects is minimized. At NREL, over the past several years, we have focused on using the high-purity float-zone (FZ) growth method to obtain controlled samples. Because the silicon melt is not in contact with a container, and no heated components are in the growth region, very high purities and low defect levels can be achieved in baseline material. The baseline can be controllably perturbed by introduction of specific defects or impurities. The chart shown below lists some of the types of defect and impurity. combinations that can be studied in this way. The boxes marked with an {open_quotes}x{close_quotes} represent combinations we have studied to some extent.

  11. The Anderson-Darling test of fit for the power law distribution from left censored samples

    CERN Document Server

    Coronel-Brizio, H F

    2010-01-01

    Maximum likelihood estimation and a test of fit based on the Anderson-Darling statistic is presented for the case of the power law distribution when the parameters are estimated from a left-censored sample. Expressions for the maximum likelihood estimators and tables of asymptotic percentage points for the A^2 statistic are given. The technique is illustrated for data from the Dow Jones Industrial Average index, an example of high theoretical and practical importance in Econophysics, Finance, Physics, Biology and, in general, in other related Sciences such as Complexity Sciences.

  12. Sampling pig farms at the abattoir in a cross-sectional study - Evaluation of a sampling method.

    Science.gov (United States)

    Birkegård, Anna Camilla; Halasa, Tariq; Toft, Nils

    2017-09-15

    A cross-sectional study design is relatively inexpensive, fast and easy to conduct when compared to other study designs. Careful planning is essential to obtaining a representative sample of the population, and the recommended approach is to use simple random sampling from an exhaustive list of units in the target population. This approach is rarely feasible in practice, and other sampling procedures must often be adopted. For example, when slaughter pigs are the target population, sampling the pigs on the slaughter line may be an alternative to on-site sampling at a list of farms. However, it is difficult to sample a large number of farms from an exact predefined list, due to the logistics and workflow of an abattoir. Therefore, it is necessary to have a systematic sampling procedure and to evaluate the obtained sample with respect to the study objective. We propose a method for 1) planning, 2) conducting, and 3) evaluating the representativeness and reproducibility of a cross-sectional study when simple random sampling is not possible. We used an example of a cross-sectional study with the aim of quantifying the association of antimicrobial resistance and antimicrobial consumption in Danish slaughter pigs. It was not possible to visit farms within the designated timeframe. Therefore, it was decided to use convenience sampling at the abattoir. Our approach was carried out in three steps: 1) planning: using data from meat inspection to plan at which abattoirs and how many farms to sample; 2) conducting: sampling was carried out at five abattoirs; 3) evaluation: representativeness was evaluated by comparing sampled and non-sampled farms, and the reproducibility of the study was assessed through simulated sampling based on meat inspection data from the period where the actual data collection was carried out. In the cross-sectional study samples were taken from 681 Danish pig farms, during five weeks from February to March 2015. The evaluation showed that the sampling

  13. SNP sets and reading ability: testing confirmation of a 10-SNP set in a population sample.

    Science.gov (United States)

    Luciano, Michelle; Montgomery, Grant W; Martin, Nicholas G; Wright, Margaret J; Bates, Timothy C

    2011-06-01

    A set of 10 SNPs associated with reading ability in 7-year-olds was reported based on initial pooled analyses of 100K SNP chip data, with follow-up testing stages using pooling and individual testing. Here we examine this association in an adolescent population sample of Australian twins and siblings (N = 1177) aged 12 to 25 years. One (rs1842129) of the 10 SNPs approached significance (P = .05) but no support was found for the remaining 9 SNPs or the SNP set itself. Results indicate that these SNPs are not associated with reading ability in an Australian population. The results are interpreted as supporting use of much larger SNP sets in common disorders where effects are small.

  14. Parameterized study of the test cover problem

    DEFF Research Database (Denmark)

    Crowston, Robert; Gutin, Gregory; Jones, Mark

    2012-01-01

    In this paper we carry out a systematic study of a natural covering problem, used for identification across several areas, in the realm of parameterized complexity. In the Test Cover problem we are given a set [n] = {1,...,n} of items together with a collection, , of distinct subsets of these items...... called tests. We assume that is a test cover, i.e., for each pair of items there is a test in containing exactly one of these items. The objective is to find a minimum size subcollection of , which is still a test cover. The generic parameterized version of Test Cover is denoted by -Test Cover. Here, we...... are given and a positive integer parameter k as input and the objective is to decide whether there is a test cover of size at most . We study four parameterizations for Test Cover and obtain the following: (a) k-Test Cover, and (n - k)-Test Cover are fixed-parameter tractable (FPT), i.e., these problems can...

  15. Microanalysis study of archaeological mural samples containing Maya blue pigment

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez del Rio, M. [ESRF, BP220, F-38043 Grenoble (France)]. E-mail: srio@esrf.fr; Martinetto, P. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Somogyi, A. [ESRF, BP220, F-38043 Grenoble (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Peltier, N. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Alianelli, L. [INFM-OGG c/o ESRF, BP220, F-38043 Grenoble Cedex (France); Moignard, B. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Pichon, L. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Calligaro, T. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Dran, J.-C. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France)

    2004-10-08

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

  16. On the matched pairs sign test using bivariate ranked set sampling ...

    African Journals Online (AJOL)

    Administrator

    2008-01-15

    Jan 15, 2008 ... control confounding in the design stage of a study, matching is a strategy that must include elements of both design and analysis”. (Hennekens and Buring 1987). For example, a two-year .... used the RSS sampling method to improve parametric and non- parametric statistical inference. For non-parametric ...

  17. Disentangling the Weight of School Dropout Predictors: A Test on Two Longitudinal Samples.

    Science.gov (United States)

    Janosz, Michel; LeBlanc, Marc; Boulerice, Bernard; Tremblay, Richard E.

    1997-01-01

    Predictors of school dropout and their stability over time were studied in 791 white French-speaking Canadian students aged 12 to 16 years in 1974 and 791 similar students in 1985 through self-administered questionnaires. School, family, behavioral, social, and personality variables predicted dropping out in both samples, and these predictors were…

  18. A test for comparing two groups of samples when analyzing multiple omics profiles

    NARCIS (Netherlands)

    Chaturvedi, N.; Goeman, J.J.; Boer, J.M.A.; Wieringen, W.N. van; Menezes, R.X. de

    2014-01-01

    BACKGROUND: A number of statistical models has been proposed for studying the association between gene expression and copy number data in integrated analysis. The next step is to compare association patterns between different groups of samples. RESULTS: We propose a method, named dSIM, to find

  19. A test for comparing two groups of samples when analyzing multiple omics profiles

    NARCIS (Netherlands)

    N. Chaturvedi (Nimisha); J.J. Goeman (Jelle); J.M. Boer (Judith); W.N. Wieringen (Wessel); R.X. de Menezes (Renee)

    2014-01-01

    textabstractBackground: A number of statistical models has been proposed for studying the association between gene expression and copy number data in integrated analysis. The next step is to compare association patterns between different groups of samples.Results: We propose a method, named dSIM, to

  20. A test for comparing two groups of samples when analyzing multiple omics profiles

    NARCIS (Netherlands)

    Chaturvedi, N.; Goeman, J.J.; Boer, J.M.; van Wieringen, W.N.; Menezes, R.

    2014-01-01

    Background: A number of statistical models has been proposed for studying the association between gene expression and copy number data in integrated analysis. The next step is to compare association patterns between different groups of samples.Results: We propose a method, named dSIM, to find

  1. Conditions Affecting the Accuracy of Classical Equating Methods for Small Samples under the NEAT Design: A Simulation Study

    Science.gov (United States)

    Sunnassee, Devdass

    2011-01-01

    Small sample equating remains a largely unexplored area of research. This study attempts to fill in some of the research gaps via a large-scale, IRT-based simulation study that evaluates the performance of seven small-sample equating methods under various test characteristic and sampling conditions. The equating methods considered are typically…

  2. Pumping tests in networks of multilevel sampling wells: Motivation and methodology

    Science.gov (United States)

    Butler, J.J.; McElwee, C.D.; Bohling, G.C.

    1999-01-01

    The identification of spatial variations in hydraulic conductivity (K) on a scale of relevance for transport investigations has proven to be a considerable challenge. Recently, a new field method for the estimation of interwell variations in K has been proposed. This method, hydraulic tomography, essentially consists of a series of short-term pumping tests performed in a tomographic-like arrangement. In order to fully realize the potential of this approach, information about lateral and vertical variations in pumping-induced head changes (drawdown) is required with detail that has previously been unobtainable in the field. Pumping tests performed in networks of multilevel sampling (MLS) wells can provide data of the needed density if drawdown can accurately and rapidly be measured in the small-diameter tubing used in such wells. Field and laboratory experiments show that accurate transient drawdown data can be obtained in the small-diameter MLS tubing either directly with miniature fiber-optic pressure sensors or indirectly using air-pressure transducers. As with data from many types of hydraulic tests, the quality of drawdown measurements from MLS tubing is quite dependent on the effectiveness of well development activities. Since MLS ports of the standard design are prone to clogging and are difficult to develop, alternate designs are necessary to ensure accurate drawdown measurements. Initial field experiments indicate that drawdown measurements obtained from pumping tests performed in MLS networks have considerable potential for providing valuable information about spatial variations in hydraulic conductivity.

  3. A Discussion of Procedures and Equipment for the Comprehensive Test Ban Treaty On-Site Inspection Environmental Sampling and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wogman, Ned A.; Milbrath, Brian D.; Payne, Rosara F.; Seifert, Carolyn E.; Friese, Judah I.; Miley, Harry S.; Bowyer, Ted W.; Hanlen, Richard C.; Onishi, Yasuo; Hayes, James C.; Wigmosta, Mark S.

    2011-02-01

    This paper is intended to serve as a scientific basis to start discussions of the available environmental sampling techniques and equipment that have been used in the past that could be considered for use within the context of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) on-site inspections (OSI). This work contains information on the techniques, equipment, costs, and some operational procedures associated with environmental sampling that have actually been used in the past by the United States for the detection of nuclear explosions. This paper also includes a discussion of issues, recommendations, and questions needing further study within the context of the sampling and analysis of aquatic materials, atmospheric gases, atmospheric particulates, vegetation, sediments and soils, fauna, and drill-back materials.

  4. Study of Composite Insulator Sheds Subjected to Wheel Test

    Directory of Open Access Journals (Sweden)

    Mackiewicz M.

    2017-06-01

    Full Text Available The paper presents investigation of the properties of the surface and the material stiffness – flexibility of series of samples taken from the sheds of the composite insulators. The insulators were previously subjected to wheel test. The wheel test and 1000 h salt fog test are regarded as alternative examination of the material resistance to the effects of electrical surface discharges. There were investigated two series of the samples of the composite insulators sheds. Examined specimens, made of HTV silicone rubber, were taken from the sheds of medium-voltage composite insulators of two different manufacturers. Insulators of both types passed the 1000 h salt fog test without reservation. Meanwhile, the wheel test can provide a basis for better distinguishing between physical properties of the tested materials. In the case of the insulators of one of the manufacturers the wheel test result was negative. Cross puncture effect of the sheds took place in several places. In addition, sheds were covered with dark coating of varying thicknesses. The results of the study indicated a significantly stronger influence of electrical and temperature factors on the sheds under investigations during the wheel test than in the case of the 1000 h salt fog test. It can be stated that these tests cannot be considered as alternative and it seems that wheel test enables better distinguishing between properties of the materials.

  5. Dipstick test for rapid diagnosis of Shigella dysenteriae 1 in bacterial cultures and its potential use on stool samples.

    Science.gov (United States)

    Taneja, Neelam; Nato, Faridabano; Dartevelle, Sylvie; Sire, Jean Marie; Garin, Benoit; Thi Phuong, Lan Nguyen; Diep, Tai The; Shako, Jean Christophe; Bimet, François; Filliol, Ingrid; Muyembe, Jean-Jacques; Ungeheuer, Marie Noëlle; Ottone, Catherine; Sansonetti, Philippe; Germani, Yves

    2011-01-01

    We describe a test for rapid detection of S. dysenteriae 1 in bacterial cultures and in stools, at the bedside of patients. The test is based on the detection of S. dysenteriae 1 lipopolysaccharide (LPS) using serotype 1-specific monoclonal antibodies coupled to gold particles and displayed on a one-step immunochromatographic dipstick. A concentration as low as 15 ng/ml of LPS was detected in distilled water and in reconstituted stools in 10 minutes. In distilled water and in reconstituted stools, an unequivocal positive reaction was obtained with 1.6×10⁶ CFU/ml and 4.9×10⁶ CFU/ml of S. dysenteriae 1, respectively. Optimal conditions to read the test have been determined to limit the risk of ambiguous results due to appearance of a faint yellow test band in some negative samples. The specificity was 100% when tested with a battery of Shigella and unrelated strains in culture. When tested on 328 clinical samples in India, Vietnam, Senegal and France by laboratory technicians and in Democratic Republic of Congo by a field technician, the specificity (312/316) was 98.7% (95% CI:96.6-99.6%) and the sensitivity (11/12) was 91.7% (95% CI:59.8-99.6%). Stool cultures and the immunochromatographic test showed concordant results in 98.4 % of cases (323/328) in comparative studies. Positive and negative predictive values were 73.3% (95% CI:44.8-91.1%) and 99.7% (95% CI:98-100%). The initial findings presented here for a simple dipstick-based test to diagnose S. dysenteriae 1 demonstrates its promising potential to become a powerful tool for case management and epidemiological surveys.

  6. On tests of treatment-covariate interactions: An illustration of appropriate power and sample size calculations.

    Science.gov (United States)

    Shieh, Gwowen

    2017-01-01

    The appraisals of treatment-covariate interaction have theoretical and substantial implications in all scientific fields. Methodologically, the detection of interaction between categorical treatment levels and continuous covariate variables is analogous to the homogeneity of regression slopes test in the context of ANCOVA. A fundamental assumption of ANCOVA is that the regression slopes associating the response variable with the covariate variable are presumed constant across treatment groups. The validity of homogeneous regression slopes accordingly is the most essential concern in traditional ANCOVA and inevitably determines the practical usefulness of research findings. In view of the limited results in current literature, this article aims to present power and sample size procedures for tests of heterogeneity between two regression slopes with particular emphasis on the stochastic feature of covariate variables. Theoretical implications and numerical investigations are presented to explicate the utility and advantage for accommodating covariate properties. The exact approach has the distinct feature of accommodating the full distributional properties of normal covariates whereas the simplified approximate methods only utilize the partial information of covariate variances. According to the overall accuracy and robustness, the exact approach is recommended over the approximate methods as a reliable tool in practical applications. The suggested power and sample size calculations can be implemented with the supplemental SAS and R programs.

  7. On tests of treatment-covariate interactions: An illustration of appropriate power and sample size calculations.

    Directory of Open Access Journals (Sweden)

    Gwowen Shieh

    Full Text Available The appraisals of treatment-covariate interaction have theoretical and substantial implications in all scientific fields. Methodologically, the detection of interaction between categorical treatment levels and continuous covariate variables is analogous to the homogeneity of regression slopes test in the context of ANCOVA. A fundamental assumption of ANCOVA is that the regression slopes associating the response variable with the covariate variable are presumed constant across treatment groups. The validity of homogeneous regression slopes accordingly is the most essential concern in traditional ANCOVA and inevitably determines the practical usefulness of research findings. In view of the limited results in current literature, this article aims to present power and sample size procedures for tests of heterogeneity between two regression slopes with particular emphasis on the stochastic feature of covariate variables. Theoretical implications and numerical investigations are presented to explicate the utility and advantage for accommodating covariate properties. The exact approach has the distinct feature of accommodating the full distributional properties of normal covariates whereas the simplified approximate methods only utilize the partial information of covariate variances. According to the overall accuracy and robustness, the exact approach is recommended over the approximate methods as a reliable tool in practical applications. The suggested power and sample size calculations can be implemented with the supplemental SAS and R programs.

  8. Cosmic veto gamma-spectrometry for Comprehensive Nuclear-Test-Ban Treaty samples

    Energy Technology Data Exchange (ETDEWEB)

    Burnett, J.L., E-mail: jonathan.burnett@awe.co.uk; Davies, A.V.

    2014-05-21

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is supported by a global network of monitoring stations that perform high-resolution gamma-spectrometry on air filter samples for the identification of 85 radionuclides. At the UK CTBT Radionuclide Laboratory (GBL15), a novel cosmic veto gamma-spectrometer has been developed to improve the sensitivity of station measurements, providing a mean background reduction of 80.8% with mean MDA improvements of 45.6%. The CTBT laboratory requirement for a {sup 140}Ba MDA is achievable after 1.5 days counting compared to 5–7 days using conventional systems. The system consists of plastic scintillation plates that detect coincident cosmic-ray interactions within an HPGe gamma-spectrometer using the Canberra Lynx{sup TM} multi-channel analyser. The detector is remotely configurable using a TCP/IP interface and requires no dedicated coincidence electronics. It would be especially useful in preventing false-positives at remote station locations (e.g. Halley, Antarctica) where sample transfer to certified laboratories is logistically difficult. The improved sensitivity has been demonstrated for a CTBT air filter sample collected after the Fukushima incident.

  9. Analysis of small-sample reactivity worths in the Fast Test Reactor Engineering Mockup Critical

    Energy Technology Data Exchange (ETDEWEB)

    Dobbin, K.D.; Daughtry, J.W.

    1976-12-01

    Small-sample reactivity worths were computed and compared with measurements at core center and along a radial traverse of the Fast Test Reactor Engineering Mockup Critical (FTR-EMC). The computed worths were obtained with first order perturbation theory using real and adjoint neutron fluxes from 42-group X-Y diffusion theory calculations. The perturbation denominator (importance-weighted neutron production rate) was obtained from three-dimensional X-Y-Z calculations. For most of the calculated worths, cross sections were from the FTR Set 300S library (essentially ENDF/B version III data); however, ENDF/B version IV delayed neutron parameters were used to generate the necessary conversion factor to allow comparison of measured and calculated worths. At core center the C/E values were 1.14 to 1.33 for plutonium samples, 1.11 for a depleted uranium sample, 0.97 to 1.05 for boron, 0.89 to 1.08 for europia, 1.4 for stainless steel and 2.6 for iron oxide.

  10. Diagnostic validity of human papillomavirus E6/E7 mRNA test in cervical cytological samples.

    Science.gov (United States)

    Liu, Tong-Yu; Xie, Rong; Luo, Li; Reilly, Kathleen H; He, Cheng; Lin, Yu-Zhen; Chen, Gang; Zheng, Xiong-Wei; Zhang, Lu-Lu; Wang, Hai-Bo

    2014-02-01

    Human papillomavirus (HPV) DNA tests tend to show high sensitivity, but poor specificity in detecting high-grade cervical lesions. This study aimed to explore the clinical performance of QuantiVirus(®) HPV E6/E7 mRNA in identifying ≥Grade 2 cervical intraepithelial neoplasia. Thin-prep(®) liquid based cytology test (LBC) samples were collected from October 2009 to October 2011 from women who underwent outpatient hospital-based gynecological screening. LBC samples were processed for E6/E7 mRNA detection and HPV DNA detection. Of 335 patients, 135 (40.3%) were HPV E6/E7 mRNA positive for high-risk HPV subtypes. The positivity rate of HPV E6/E7 mRNA increased with the severity of cytological and histological evaluation. An optimal cut-off value of ≥567copies/ml was determined using receiver operating characteristic (ROC) curve, and positive predictive value and negative predictive value of cut-off value (≥567copies/ml) were higher than those of E6/E7 mRNA positivity only, but not significant. QuantiVirus(®) HPV E6/E7 mRNA testing may be a valuable tool in triage for identifying ≥Grade 2 cervical intraepithelial neoplasia. A high specificity and a low positivity rate of E6/E7mRNA testing as a triage test in HPV DNA-positive women can be translated into a low referral for colposcopy. Studies composed of large population-based samples of women and with rigorous disease ascertainment, are needed to establish the optimal cut-off point based on ROC curve analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. A single mini-barcode test to screen for Australian mammalian predators from environmental samples.

    Science.gov (United States)

    Modave, Elodie; MacDonald, Anna J; Sarre, Stephen D

    2017-08-01

    Identification of species from trace samples is now possible through the comparison of diagnostic DNA fragments against reference DNA sequence databases. DNA detection of animals from non-invasive samples, such as predator faeces (scats) that contain traces of DNA from their species of origin, has proved to be a valuable tool for the management of elusive wildlife. However, application of this approach can be limited by the availability of appropriate genetic markers. Scat DNA is often degraded, meaning that longer DNA sequences, including standard DNA barcoding markers, are difficult to recover. Instead, targeted short diagnostic markers are required to serve as diagnostic mini-barcodes. The mitochondrial genome is a useful source of such trace DNA markers because it provides good resolution at the species level and occurs in high copy numbers per cell. We developed a mini-barcode based on a short (178 bp) fragment of the conserved 12S ribosomal ribonucleic acid mitochondrial gene sequence, with the goal of discriminating amongst the scats of large mammalian predators of Australia. We tested the sensitivity and specificity of our primers and can accurately detect and discriminate amongst quolls, cats, dogs, foxes, and devils from trace DNA samples. Our approach provides a cost-effective, time-efficient, and non-invasive tool that enables identification of all 8 medium-large mammal predators in Australia, including native and introduced species, using a single test. With modification, this approach is likely to be of broad applicability elsewhere. © The Authors 2017. Published by Oxford University Press.

  12. Noninvasive buccal swab antigen sample and molecular testing provides extended antigen typing for patients with hemoglobinopathies.

    Science.gov (United States)

    Rampersad, Angeli; Hampton, Kisha; Duncan, Natalie; Roberson, Chris; Slayten, Jayanna; Davisson, Suzanne; Aronowitz, Jessica; Shapiro, Amy

    2014-11-01

    To demonstrate the feasibility of performing a noninvasive, molecular-based red blood cell (RBC) antigen test on infants and very young children with sickle cell disease as part of a statewide newborn screening follow-up program. A prospective pilot project was conducted using a noninvasive buccal swab and test kit to perform DNA-based, extended RBC phenotyping in 92 children participating in a newborn hemoglobinopathy screening follow-up program. Reported data include the extended panel of antigens detected by molecular analysis compared with unaffected population estimates. Molecular-based RBC antigen testing was successful, with extended RBC typing generated for all subjects. Molecular testing detected several rare negative or rare positive phenotypes, demonstrating the utility of obtaining an extended antigen panel. This study demonstrates the feasibility of performing antigen testing on buccal swab specimens from children with sickle cell disease as part of a newborn screening follow-up program with the aim of allowing specific unit matching to prevent alloimmunization with RBC transfusions. The general applicability of testing may be limited by a lack of uniform insurance coverage for buccal swab testing, however. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. [Evaluation of the diagnostic performance of Xpert MTB/RIF test for the detection of Mycobacterium tuberculosis and rifampin resistance in clinical samples].

    Science.gov (United States)

    Gürsoy, Nafia Canan; Yakupoğulları, Yusuf; Tekerekoğlu, Mehmet Sait; Otlu, Barış

    2016-04-01

    Rapid and accurate detection of active tuberculosis (TB) cases is one of the most important goal of tuberculosis control programme. For this purpose, new methods are being developed to isolate, serotype and determine the drug resistance of the agent. Xpert MTB/RIF test (CepheidGeneXpert® System, USA) that has been recently developed, is a real-time polymerase chain reaction-based method which detects Mycobacterium tuberculosis complex and resistance of the strain to rifampicin (RIF) from the clinical sample directly within a couple of hours. However, there are not sufficient data about the performance of that test for extrapulmonary samples and pulmonary samples other than sputum. The aims of this study were to investigate the sensitivity, specificity, positive and negative predictive values of Xpert MTB/RIF test in detection of M. tuberculosis and the performance in the determination of rifampicin resistance of the isolates from pulmonary and extrapulmonary clinical samples. A total of 2160 clinical samples, in which 1141 (52.8%) were pulmonary and 1019 (47.2%) were extrapulmonary samples, sent to our laboratory between July 2013 to December 2014, were included in the study. Sixty seven of the evaluated samples (3.1%) were positive with microscopy (acid-fast stain; AFS), 116 samples (5.1%) were positive with culture and 98 samples (4.5%) were positive with Xpert MTB/RIF test. When the culture was considered as the reference method, the sensitivity and specificity of Xpert MTB/RIF test were determined as 73.3% and 99.3%, respectively for all samples; 77.5% and 99.5%, respectively for pulmonary samples and 63.9% and 99.2%, respectively for extrapulmonary samples. Among AFS positive samples, the sensitivity was 100% and specificity was 66.7%; whereas among AFS negative samples those values were 40.4% and 99.4%, respectively. Among all the samples involved in the study, RIF resistance was determined only in three samples with Xpert MTB/ RIF test and that was also

  14. Small-Sample Adjustments for Tests of Moderators and Model Fit in Robust Variance Estimation in Meta-Regression

    Science.gov (United States)

    Tipton, Elizabeth; Pustejovsky, James E.

    2015-01-01

    Randomized experiments are commonly used to evaluate the effectiveness of educational interventions. The goal of the present investigation is to develop small-sample corrections for multiple contrast hypothesis tests (i.e., F-tests) such as the omnibus test of meta-regression fit or a test for equality of three or more levels of a categorical…

  15. Trait aggression in two representative U.S. surveys: Testing the generalizability of college samples.

    Science.gov (United States)

    Kalmoe, Nathan P

    2015-03-01

    Aggression research often relies upon convenient samples with unknown generalizability to populations of interest, potentially threatening external validity. This article details the measurement properties of the Buss-Perry Aggression Questionnaire Short Form (BPAQ-SF) and its subscales in two nationally representative U.S. samples (N = 924) and a concurrent study with U.S. college students (N = 384). The results provide useful benchmarks for generalizing BPAQ-SF results from convenient samples to U.S. adults, including distributions, reliability, and factor structure. The results also confirm basic relationships between trait aggression and key social and demographic variables such as sex, age, and socioeconomic status while establishing convergent validity with violent political attitudes. Results from the national studies closely align with those from the student sample, providing reasonable support for generalizing trait aggression elements to U.S. adults. Aggr. Behav. Aggr. Behav. 42:171-188, 2015. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  16. Health Orientation, Knowledge, and Attitudes toward Genetic Testing and Personalized Genomic Services: Preliminary Data from an Italian Sample

    Directory of Open Access Journals (Sweden)

    Serena Oliveri

    2016-01-01

    Full Text Available Objective. The study aims at assessing personality tendencies and orientations that could be closely correlated with knowledge, awareness, and interest toward undergoing genetic testing. Methods. A sample of 145 subjects in Italy completed an online survey, investigating demographic data, health orientation, level of perceived knowledge about genetic risk, genetic screening, and personal attitudes toward direct to consumer genetic testing (DTCGT. Results. Results showed that respondents considered genetic assessment to be helpful for disease prevention, but they were concerned that results could affect their life planning with little clinical utility. Furthermore, a very high percentage of respondents (67% had never heard about genetic testing directly available to the public. Data showed that personality tendencies, such as personal health consciousness, health internal control, health esteem, and confidence, motivation to avoid unhealthiness and motivation for healthiness affected the uptake of genetic information and the interest in undergoing genetic testing. Conclusions. Public knowledge and attitudes toward genetic risk and genetic testing among European countries, along with individual personality and psychological tendencies that could affect these attitudes, remain unexplored. The present study constitutes one of the first attempts to investigate how such personality tendencies could motivation to undergo genetic testing and engagement in lifestyle changes.

  17. TRU Waste Sampling Program: Volume II. Gas generation studies

    Energy Technology Data Exchange (ETDEWEB)

    Clements, T.L. Jr.; Kudera, D.E.

    1985-09-01

    Volume II of the TRU Waste Sampling Program report contains the data generated from evaluating the adequacy of venting/filtering devices for maintaining safe hydrogen levels in plutonium contaminated waste drums. Additional studies reported in this volume include gas generation rates, selected waste form monitoring, and evaluation of hydrogen migration from sealed 90-mil rigid polyethylene drum liners containing /sup 238/Pu-contaminated wastes. All wastes used in the studies were newly-generated, and the waste drums were under controlled, experimental conditions. Studies using /sup 239/Pu-contaminated wastes were conducted at the Rocky Flats Plant. Studies using /sup 238/Pu-contaminated wastes were conducted at the Los Alamos National Laboratory.

  18. Aptamer-Based Lateral Flow Test Strip for Rapid Detection of Zearalenone in Corn Samples.

    Science.gov (United States)

    Wu, Shijia; Liu, Lihong; Duan, Nuo; Li, Qian; Zhou, You; Wang, Zhouping

    2018-02-28

    An aptamer-based lateral flow test strip was developed for the detection of zearalenone (ZEN). This assay was based on the competition for the aptamer between ZEN and its complementary sequence. Several experimental conditions that could influence sensitivity have been investigated, including the concentration of aptamer and NaCl used in the probe preparation, the mole ratio of streptavidin and biotinylated DNA used in the preparation of test line and control line, and the loading quantity of gold nanoparticles-aptamer conjugates (AuNPs-Apt). Under the optimal experimental conditions, we successfully detected ZEN within a detection range of 5-200 ng/mL and the visual limit of detection of 20 ng/mL. This aptamer-based strip was successfully applied to the determination of ZEN in spiked corn samples, and the recoveries were from 93.4% to 114.2%. All detections can be achieved within 5 min. The results demonstrated that the developed aptamer-based lateral flow test strip is a potential alternative tool for the rapid and sensitive detection of ZEN.

  19. Effectiveness of quadrat sampling on terrestrial cave fauna survey - a case study in a Neotropical cave

    Directory of Open Access Journals (Sweden)

    Maria Elina Bichuette

    2015-07-01

    Full Text Available Quadrat sampling is a method used for a long time in plant ecology studies but only recently it has been used with focus on fauna. For the cave fauna samplings, there are rare works applying this methodology. The present study compared the methods of quadrat sampling with direct search qualitative for terrestrial cave fauna. For this, we conducted five sampling collections in a limestone cave in central Brazil. Quadrat sampling contributed with 121 exclusive species and 716 specimens and direct search qualitative method contributed with 91 exclusive species and 355 specimens. Mann-Whitney test evidenced significant differences between the two methods. We demonstrated that quadrat sampling method was slightly more efficient to analyze the species richness and much more effective to assess the abundance than the use of only direct search qualitative method, mainly considering tiny and/or cryptobiotic invertebrates (e.g., earth worms, symphylans, psocopterans, trichopterans, dipterans, small spiders, and small isopods. We recommend the association of different methods to test patterns in cave fauna, since incomplete sampling may lead to erroneous estimates and equivocated decisions about management, impact studies and cave conservation.

  20. Journal: A Review of Some Tracer-Test Design Equations for Tracer-Mass Estimation and Sample Collection Frequency

    Science.gov (United States)

    Determination of necessary tracer mass, initial sample-collection time, and subsequent sample-collection frequency are the three most difficult aspects to estimate for a proposed tracer test prior to conducting the tracer test. To facilitate tracer-mass estimation, 33 mass-estima...

  1. Salivary gland tumours in a Mexican sample. A retrospective study.

    Science.gov (United States)

    Ledesma-Montes, C; Garces-Ortiz, M

    2002-01-01

    Salivary gland tumours are an important part of the Oral and Maxillofacial Pathology, unfortunately, only few studies on these tumours have been done in Latin-American population. The aim of this study was to compare demographic data on salivary gland tumours in a Mexican sample with those previously published from Latin American and non-Latin American countries. All cases of salivary gland tumours or lesions diagnosed in our service were reviewed. Of the reviewed cases,67 were confirmed as salivary gland tumours. Out of these 64.2% were benign neoplasms, 35.8% were malignant and a slight female predominance (56.7%) was found. The most common location was palate followed by lips and floor of the mouth. Mean age for benign tumours was 40.6 years with female predominance (60.5%). Mean age for malignant tumours was 41 years and female predominance was found again. Palate followed by retromolar area were the usual locations. Pleomorphic adenoma (58.2%), mucoepidermoid carcinoma (17.9%) and adenoid cystic carcinoma (11.9%) were the more frequent neoplasms. All retromolar cases were malignant and all submandibular gland tumours were benign. We found a high proportion of salivary gland neoplasms in children. Our results showed that differences of the studied tumours among our sample and previously reported series exist. These differences can be related to race and geographical location.

  2. Test results of the first 50 kA NbTi full size sample for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Ciazynski, D.; Zani, L. [Association Euratom-CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Ciotti, M.; Gislon, P.; Spadoni, M. [Association Euratom-ENEA sulla Fusione Centro Ricerche Energia Frascati (Italy); Huber, S.; Stepanov, B. [Association Euratom-Confederation Suisse, EPFL, CRPP-TF, Villigen (Switzerland); Karlemo, B. [European Fusion Development Agreement - Close Support Unit (EFDA/CSU), Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    2003-07-01

    Within the framework of the research studies for the International Thermonuclear Experimental Reactor (ITER) project, the first full size NbTi conductor sample was fabricated in industry and tested in the SULTAN facility (Villigen, Switzerland). This sample (PF-FSJS), which is relevant to the Poloidal Field coils of ITER, is composed of two parallel straight bars of conductor, connected at bottom through a joint designed according to the Cea twin-box concept. The two conductor legs are identical except for the use of different strands: a nickel plated NbTi strand with a pure copper matrix in one leg, and a bare NbTi strand with copper matrix and internal CuNi barrier in the other leg. The two conductors and the joint were extensively tested regarding DC (direct current) and AC (alternative current) properties. This paper reports on the tests results and analysis, stressing the differences between the two conductor legs and discussing the impact of the test results on the ITER design criteria for conductor and joint. While joint DC resistance, conductors and joint AC losses, fulfilled the ITER requirements, neither conductor could reach its current sharing temperature at relevant ITER currents, due to instabilities. Although the drop in temperature is slight for the CuNi strand cable, it is more significant for the Ni plated strand cable. (authors)

  3. {sup 15}N metabolic test for the determination of phytotoxic effects of chemicals and contaminated environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Jung, K.; Segner, H.; Schueuermann, G. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Leipzig (Germany). Sektion Chemische Oekotoxikologie; Kaletta, K. [Halle-Wittenberg Univ., Halle (Germany). Inst. fuer Biochemie

    1999-07-01

    A stable isotope {sup 15}N-nitrogen test (ESIMA=Ecotoxicological Stable Isotope Metabolic Assay) was developed to assess biological effects and the potential toxicological hazard of chemicals and contaminated environmental samples on plant metabolism. The assay measures the effect of toxicants on the incorporation of a {sup 15}N labelled tracer into the total nitrogen fraction (both the nonprotein and protein fraction) of plants. Segments of Pisum arvense epicotyls are used as test substrates because of their high metabolic activity. The plant material is incubated under standardised conditions for two hours; subsequently {sup 15}N incorporation is analysed by determining the {sup 15}N abundance ({sup 15}N atom-%) in the epicotyl segments. The effects of toxicants are evaluated by comparing the {sup 15}N incorporation rates of control tissue and epicotyl segments exposed to individual chemicals or complex environmental samples. The specificity and sensitivity of effects as indicated by ESIMA were compared with effect as measured by two establish ecotoxicological bioassays, the pollen tube growth test using pollen of Nicotiana sylvestris and the bacterial luminescence inhibition test using pollen of Photobacterium phosphoreum. The results of the study clearly indicate the suitability of ESIMA for assessing toxic impacts on plant nitrogen metabolism. (orig.)

  4. Psychometric Quality of the Dutch Version of the Children's Eating Attitude Test in a Community Sample and a Sample of Overweight Youngsters

    Directory of Open Access Journals (Sweden)

    Lotte Theuwis

    2010-12-01

    Full Text Available Introduction. Disturbed eating attitudes may be important precursors of pathological eating patterns and, therefore need to be researched adequately. The Children's Eating Attitude Test (ChEAT is indicated for detecting at-risk attitudes and concerns in youngsters. Method. The present study was designed to provide a preliminary psychometric evaluation of the Dutch version of the ChEAT, by examining reliability and validity in a sample of 166 youngsters. Results. Generally the ChEAT seems to be a reliable instrument. Concurrent validity was demonstrated by positive correlations with measures assessing pathological eating behaviour and with related psychological problems. The discriminant validity was good. Based on ChEAT scores we can distinguish overweight youngsters from the community sample and “dieters” from “non dieters”. Divergent validity and factor structure show still shortcomings. Discussion. The Dutch version of the ChEAT seems to be a promising screening- and research instrument. Future prospective research could focus on a cut-off score for identifying at-risk youngsters.

  5. Social Connectedness and Life Satisfaction: Comparing Mean Levels for 2 Undergraduate Samples and Testing for Improvement Based on Brief Counseling

    Science.gov (United States)

    Blau, Gary; DiMino, John; DeMaria, Peter A.; Beverly, Clyde; Chessler, Marcy; Drennan, Rob

    2016-01-01

    Objectives: Comparing the mean levels of social connectedness and life satisfaction, and analyzing their relationship for 2 undergraduate samples, and testing for an increase in their means for a brief counseling sample. Participants: Between October 2013 and May 2015, 3 samples were collected: not-in-counseling (NIC; n = 941), initial counseling…

  6. Efficiency of Direct Microscopy of Stool Samples Using an Antigen-Specific Adhesin Test for Entamoeba Histolytica.

    Science.gov (United States)

    İrvem, Arzu; Özdil, Kamil; Çalışkan, Zuhal; Yücel, Muhterem

    2016-09-01

    E. histolytica is among the common causes of acute gastroenteritis. The pathogenic species E. histolytica and the nonpathogenic species E. dispar cannot be morphologically differentiated, although correct identification of these protozoans is important for treatment and public health. In many laboratories, the screening of leukocytes, erythrocytes, amoebic cysts, trophozoites and parasite eggs is performed using Native-Lugol's iodine for pre-diagnosis. In this study, we aimed to investigate the frequency of E. histolytica in stool samples collected from 788 patients residing in the Anatolian region of İstanbul who presented with gastrointestinal complaints. We used the information obtained to evaluate the effectiveness of microscopic examinations when used in combination with the E. histolytica adhesin antigen test. Retrospective cross-sectional study. Preparations of stool samples stained with Native-Lugol's iodine were evaluated using the E. histolytica adhesin test and examined using standard light microscopy at ×40 magnification. Pearson's Chi-square and Fisher's exact tests were used for statistical analysis. Logistic regression analysis was used for multivariate analysis. Of 788 samples, 38 (4.8%) were positive for E. histolytica adhesin antigens. When evaluated together with the presences of erythrocytes, leukocytes, cysts, and trophozoites, respectively, using logistic regression analysis, leukocyte positivity was significantly higher. The odds ratio of leukocyte positivity increased adhesin test-positivity by 2,530-fold (95% CI=1.01-6.330). Adhesin test-positivity was significant (p=0.047). In line with these findings, the consistency between the presence of cysts and erythrocytes and adhesin test-positivity was found to be highly significant, but that of higher levels of leukocytes was found to be discordant. It was concluded that leukocytes and trophozoites were easily misjudged using direct microscopy. Although microscopic examination of samples

  7. Dynamic Sampling of Trace Contaminants During the Mission Operations Test of the Deep Space Habitat

    Science.gov (United States)

    Monje, Oscar; Valling, Simo; Cornish, Jim

    2013-01-01

    The atmospheric composition inside spacecraft during long duration space missions is dynamic due to changes in the living and working environment of crew members, crew metabolism and payload operations. A portable FTIR gas analyzer was used to monitor the atmospheric composition within the Deep Space Habitat (DSH) during the Mission Operations Test (MOT) conducted at the Johnson Space Center (JSC). The FTIR monitored up to 20 gases in near- real time. The procedures developed for operating the FTIR were successful and data was collected with the FTIR at 5 minute intervals. Not all the 20 gases sampled were detected in all the modules and it was possible to measure dynamic changes in trace contaminant concentrations that were related to crew activities involving exercise and meal preparation.

  8. Dynamic Sampling of Cabin VOCs during the Mission Operations Test of the Deep Space Habitat

    Science.gov (United States)

    Monje, Oscar; Rojdev, Kristina

    2013-01-01

    The atmospheric composition inside spacecraft is dynamic due to changes in crew metabolism and payload operations. A portable FTIR gas analyzer was used to monitor the atmospheric composition of four modules (Core lab, Veggie Plant Atrium, Hygiene module, and Xhab loft) within the Deep Space Habitat '(DSH) during the Mission Operations Test (MOT) conducted at the Johnson Space Center. The FTIR was either physically relocated to a new location or the plumbing was changed so that a different location was monitored. An application composed of 20 gases was used and the FTIR was zeroed using N2 gas every time it was relocated. The procedures developed for operating the FTIR were successful as all data was collected and the FTIR worked during the entire MOT mission. Not all the 20 gases in the application sampled were detected and it was possible to measure dynamic VOC concentrations in each DSH location.

  9. Saliva sampling in global clinical studies: the impact of low sampling volume on performance of DNA in downstream genotyping experiments

    Science.gov (United States)

    2013-01-01

    Background The collection of viable DNA samples is an essential element of any genetics research programme. Biological samples for DNA purification are now routinely collected in many studies with a variety of sampling methods available. Initial observation in this study suggested a reduced genotyping success rate of some saliva derived DNA samples when compared to blood derived DNA samples prompting further investigation. Methods Genotyping success rate was investigated to assess the suitability of using saliva samples in future safety and efficacy pharmacogenetics experiments. The Oragene® OG-300 DNA Self-Collection kit was used to collect and extract DNA from saliva from 1468 subjects enrolled in global clinical studies. Statistical analysis evaluated the impact of saliva sample volume of collection on the quality, yield, concentration and performance of saliva DNA in genotyping assays. Results Across 13 global clinical studies that utilized the Oragene® OG-300 DNA Self-Collection kit there was variability in the volume of saliva sample collection with ~31% of participants providing 0.5 mL of saliva, rather than the recommended 2 mL. While the majority of saliva DNA samples provided high quality genotype data, collection of 0.5 mL volumes of saliva contributed to DNA samples being significantly less likely to pass genotyping quality control standards. Assessment of DNA sample characteristics that may influence genotyping outcomes indicated that saliva sample volume, DNA purity and turbidity were independently associated with sample genotype pass rate, but that saliva collection volume had the greatest effect. Conclusion When employing saliva sampling to obtain DNA, it is important to encourage all study participants to provide sufficient sample to minimize potential loss of data in downstream genotyping experiments. PMID:23759220

  10. The factor analytic structure of the Roberts Apperception Test for Children: a comparison of the standardization sample with a sample of chronically ill children.

    Science.gov (United States)

    Palomares, R S; Crowley, S L; Worchel, F F; Olson, T K; Rae, W A

    1991-06-01

    A confirmatory principal component factor analysis of the Roberts Apperception Test for Children was conducted using the standardization sample and a sample of chronically ill children. An interpretation of three- and four-factor solutions identified the three-factor solution as superior to the four-factor solution as measured by chi-square goodness of fit and coefficients of convergence. A cluster analysis using Ward's minimum variance method was calculated to determine the typical profiles that best describe the chronically ill sample. Results of this analysis reveal two distinct profiles that differ primarily on the level of adaptive psychological functioning.

  11. Analysis and tests of TF magnet insulation samples for the JET upgrade to 4 tesla

    CERN Document Server

    Miele, P; Bettinali, L; Kaye, A; Last, J; Papastergiou, S; Riccardo, V; Visca, E

    2000-01-01

    The JET Toroidal Field (TF) coils were originally designed for operation at 3.4 tesla. In order to upgrade the field to 4 tesla and thus improve the performance of the JET machine, new mechanical tests and analysis were carried out on the insulation of TF coil samples. They are aimed at investigating the mechanical properties and the status of the insulation in order to set allowable stresses and force limits. In particular since the shear stress in the insulation is strongly affected by the shear modulus of elasticity G, it is important to measure this parameter. A method for the measurement of G in glass-resin fibres, the V-notched beam method (Iosipescu method) , was applied. The particular shape of the rectangular Iosipescu V- notched sample and the particular modality of force application produce pure shear stress for a reliable measurement of the G value and of the shear strength of the insulation. The effect of temperature on these mechanical properties was also investigated. Results show higher averag...

  12. Multiscale study for stochastic characterization of shale samples

    Science.gov (United States)

    Tahmasebi, Pejman; Javadpour, Farzam; Sahimi, Muhammad; Piri, Mohammad

    2016-03-01

    are tested on two shale samples for which full 3D samples are available. The quantitative accuracy of the models is demonstrated by computing their morphological and flow properties and comparing them with those of the actual 3D images. The success of the method hinges upon the use of very different low- and high-resolution images.

  13. Determining urine sample mutagenicity ratio using Ames test: Tehran forensic medicine laboratory personnels

    Directory of Open Access Journals (Sweden)

    Partoazar A

    2009-06-01

    Full Text Available "n Normal 0 false false false EN-GB X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Cancer prevention besides detection and treatment has a very important role in control of cancer disease. Since some chemical compounds that are used in laboratories, especially in pathology laboratory are potentially mutagens, lab assistances that are working with chemicals such as Benzene, Xylazine and Formaldehyde for long period of time may be exposed to overload of these carcinogens. Therefore, it is necessary to use an indicator for detecting these occupational exposures. Ames test has been recommended in biomonitoring of environment that has high risk carcinogenicity characteristic."n"nMethods: A total of fifty seven urine samples of forensic medicine laboratory personnel's were extracted by C18 column and then tested by TA100 and TA98 standard strains of Ames assay. Each sample was analyzed with and without activator to detect mutagen and promutagen materials."n"nResults: Levels of mutagenicity were found by TA98 strain without activator in one case as well as with activator in two cases of urine samples of pathology laboratory personnel's. These cases were working in laboratory for long time in all of the workdays."n"nConclusion: Personnel's working in pathology laboratories may have

  14. Molding of strength testing samples using modern PDCPD material for purpose of automotive industry

    Science.gov (United States)

    Grabowski, L.; Baier, A.; Sobek, M.

    2017-08-01

    The casting of metal materials is widely known but the molding of composite polymer materials is not well-known method still. The initial choice of method for producing composite bodies was the method of casting of PDCPD material. For purpose of performing casting of polymer composite material, a special mold was made. Firstly, the 3D printed, using PLA material, mold was used. After several attempts of casting PDCPD many problems were encountered. The second step was to use mold milled from a firm and dense isocyanate foam. After several attempts research shown that this solution is more resistant to high-temperature peak, but this material is too fragile to use it several times. This solution also prevents mold from using external heating, which can be necessary for performing correct molding process. The last process was to use the aluminum mold, which is dedicated to PDCPD polymer composite, because of low adhesiveness. This solution leads to perform correct PDCPD polymer composite material injection. After performing casting operation every PDCPD testing samples were tested. These results were compared together. The result of performed work was to archive correct properties of injection of composite material. Research and results were described in detail in this paper.

  15. Quantitative Study on Exact Reconstruction Sampling Condition in Limited-view CT

    CERN Document Server

    Yan, Bin; Li, Lei; Zhang, Hanming; Wang, Linyuan

    2016-01-01

    In limited-view computed tomography reconstruction, iterative image reconstruction with sparsity-exploiting methods, such as total variation (TV) minimization, inspired by compressive sensing, potentially claims large reductions in sampling requirements. However, a quantitative notion of this claim is non-trivial because of the ill-defined reduction in sampling achieved by the sparsity-exploiting method. In this paper, exact reconstruction sampling condition for limited-view problem is studied by verifying the uniqueness of solution in TV minimization model. Uniqueness is tested by solving a convex optimization problem derived from the sufficient and necessary condition of solution uniqueness. Through this method, the sufficient sampling number of exact reconstruction is quantified for any fixed phantom and settled geometrical parameter in the limited-view problem. This paper provides a reference to quantify the sampling condition. Using Shepp-Logan phantom as an example, the experiment results show the quant...

  16. Study population, questionnaire, data management and sample description.

    Science.gov (United States)

    de Waure, Chiara; Poscia, Andrea; Virdis, Andrea; Di Pietro, Maria Luisa; Ricciardi, Walter

    2015-01-01

    This article describes methodological issues of the "Sportello Salute Giovani" project ("Youth Health Information Desk"), a multicenter study aimed at assessing the health status and attitudes and behaviours of university students in Italy. The questionnaire used to carry out the study was adapted from the Italian health behaviours in school-aged children (HBSC) project and consisted of 93 items addressing: demographics; nutritional habits and status; physical activity; lifestyles; reproductive and preconception health; health and satisfaction of life; attitudes and behaviours toward academic study and new technologies. The questionnaire was administered to a pool of 12 000 students from 18 to 30 years of age who voluntary decided to participate during classes held at different Italian faculties or at the three "Sportello Salute Giovani" centers which were established in the three sites of the Università Cattolica del Sacro Cuore (Catholic University of the Sacred Heart of Rome). The final study sample was composed by 8516 university students. The mean age of responders was 22.2 (Standard Deviation 2.0) and 5702 (67.0%) were females. According to the distribution in age classes, 3601 (43.3%) belonged to the 18-21 one, 3796 (44.5%) to the 22-24 class and 1019 (12.2%) to the 25-30 class. With respect to socio-economic status, data were available for 8410 responders and showed that 50.3% of students belonged to the middle class. The project took into consideration a large number of individuals from different regions of the country and therefore may be considered representative of the general population of Italian university students. Furthermore, it is the first to address, at the same time, several issues, in particular attitudes and behaviours toward health, in Italian university students. The analysis of data from such a large sample of university students sets the basis for identifying the most appropriate interventions in order to address the specific needs of

  17. Multiple Hypotheses Testing Procedures in Clinical Trials and Genomic Studies

    Directory of Open Access Journals (Sweden)

    Qing ePan

    2013-12-01

    Full Text Available We review and compare multiple hypothesis testing procedures used in clinical trials and those in genomic studies. Clinical trials often employ global tests, which draw an overall conclusion for all the hypotheses, such as SUM test, Two-Step test, Approximate Likelihood Ratio test (ALRT, Intersection Union Test (IUT and MAX test. The SUM and Two-Step tests are most powerful under homogeneous treatment effects, while the ALRT and MAX test are robust in cases with nonhomogeneous treatment effects. Furthermore, the ALRT is robust to unequal sample sizes across endpoints. In genomic studies, stepwise procedures are used to draw marker-specific conclusions and control family wise error rate (FWER or false discovery rate (FDR at the same time. FDR refers to the percent of false positives among all significant results and is preferred over FWER in screening high-dimensional genomic markers due to its interpretability. In cases where correlations between test statistics cannot be ignored, Westfall-Young resampling method can be employed to generate the joint distribution of P-values under the null and maintain their correlation structure. Finally, the GWAS from a clinical trial studying microvascular complications among Type 1 diabetes patients is used to illustrate various procedures.

  18. Testing the effects of educational toilet posters: a novel way of reducing haemolysis of blood samples within ED.

    Science.gov (United States)

    Corkill, David

    2012-02-01

    Haemolysed blood samples are an unnecessary burden on Emergency Departments (ED) as they increase workloads and drive down efficiencies. Little empirical data exists that demonstrates the effectiveness of educational posters displayed in staff toilet cubicles. This study explored the impact educational toilet posters have on reducing haemolysis rates within the ED. A time series study of the clinical effect of educational toilet posters on reducing haemolysis rates throughout a 12 month period at the Gold Coast Hospital ED was undertaken. The GCH ED is a tertiary emergency service that has approximately 66,000 patient presentations per year. Data was collected prospectively. Analysis was undertaken to investigate the effects on total number of haemolysed samples and those clinically significant samples with a haemolytic index >3. Further investigation explored the specific effects on medical and nursing staff. Analysis undertaken using an independent t-test found that the pre-intervention data demonstrates a medium haemolysis rate of 4.92% (SD=1.04). This is a statistically significantly different (t=3.56, df=50, p=0.001) from the median post intervention data of 3.95% (SD=0.84). The difference of 0.97% (95%CI=0.42, 1.52) represents a 19.72% reduction in clinically significant haemolysed samples over the study period. This study reveals that the use of educational toilet posters had a positive impact on reducing the rates of haemolysed samples collected within the ED. This simple and cost effective educational initiative changed the behaviour of clinical staff. Further investigation is warranted to examine the impact of educational toilet posters on additional clinical scenarios. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  19. Visualizing shear bands in 3-D using axisymmetric sample: An experimental study

    Directory of Open Access Journals (Sweden)

    W. Khraisat

    2017-07-01

    Full Text Available In this study a qualitative description of the occurrence of shear bands produced by a sudden impact on an axisymmetric specimen made of medium carbon steel 0.45% C is given. A simple experiment was developed aimed at producing a pinch shear stress in the front side of the test sample in order to visualize shear bands in 3-D. Curve fitting using MATLAB was employed based on the points taken from the images of the front section of the test sample. The predictions of the curve fitting suggests a hyperbolic section leading to the conclusion that within the sample there is a double cone region of material where the shear band region is located on its outer surface. The formation of the shear band is explained by the fact that the interaction of the stress wave front with the free surface of the test sample produces reflection waves that attenuate the incoming stress wave inwards leading to a stress gradient in the plane of the front side of the specimen that causes shear localization. Also, the progressively increasing cross sectional area of the test sample causes the expansion of the wave front, which also results in a stress gradient in the normal direction of the front side of the specimen. So the formation of shear bands depends not only on the impact momentum and strain rates but also on the sample’s geometry.

  20. Results of Hg speciation testing on tank 39 and 1Q16 tank 50 samples

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-03-07

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences, Inc. in Seattle, WA on behalf of the Savannah River Remediation (SRR) Mercury Task Team.i,ii The seventeenth shipment of samples was designated to include two Tank 39 samples and the 1Q16 Tank 50 Quarterly WAC sample. The surface Tank 39 sample was pulled at 262.1” from the tank bottom, and the depth Tank 39 sample was pulled at 95” from the tank bottom. The 1Q16 Tank 50 WAC sample was drawn from the 1-L variable depth sample received by SRNL.

  1. Supervised blood-based self-sample collection and rapid test performance: a valuable alternative to the use of saliva by HIV testing programmes with no medical or nursing staff.

    Science.gov (United States)

    Belza, María J; Rosales-Statkus, M Elena; Hoyos, Juan; Segura, Pilar; Ferreras, Eva; Sánchez, Rebeca; Molist, Gemma; de la Fuente, Luis

    2012-04-01

    Some saliva-based HIV testing programmes have resulted in an unacceptable percentage of false positives. Many countries require blood-based testing programmes to have doctors/nurses. The authors evaluate whether, after brief training and under the supervision of a skilled counsellor, blood-based self-sample collection and rapid test performance could be a valuable alternative. 208 Spanish-speaking attendees at a street-based HIV testing programme in Madrid participated in the study. Participants were tested twice, first in the study and then in the programme, using the same finger-stick whole-blood rapid test (Determine HIV-1/2 Ag/Ab Combo®). Based on previously adapted instructions, the study counsellor explained the procedure to follow throughout the test. Participants then performed the test under the guidance of the counsellor. Demographic and risk behaviour data were collected by a self-administered questionnaire. The test results in the programme and the study were read by the study counsellor. 99.0% (95% CI 96.6% to 99.9%) of participants had a valid result in the study test, the same percentage as in the programme test conducted by the doctor/nurse. Two persons had invalid test results in both the study and the programme, but they were not the same persons. The study provides clear evidence that this methodology is a valuable alternative to saliva for HIV testing programmes when medical or nursing staff required to take blood samples is not available.

  2. Evaluation of Legionella Air Contamination in Healthcare Facilities by Different Sampling Methods: An Italian Multicenter Study

    Directory of Open Access Journals (Sweden)

    Maria Teresa Montagna

    2017-06-01

    Full Text Available Healthcare facilities (HF represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis®μ and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis®μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT methods. Air contamination was found in four HF (36.4% by at least one of the culturable methods. The culturable investigation by Coriolis®μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis®μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations.

  3. Evaluation of Legionella Air Contamination in Healthcare Facilities by Different Sampling Methods: An Italian Multicenter Study.

    Science.gov (United States)

    Montagna, Maria Teresa; De Giglio, Osvalda; Cristina, Maria Luisa; Napoli, Christian; Pacifico, Claudia; Agodi, Antonella; Baldovin, Tatjana; Casini, Beatrice; Coniglio, Maria Anna; D'Errico, Marcello Mario; Delia, Santi Antonino; Deriu, Maria Grazia; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Moro, Matteo; Mura, Ida; Pennino, Francesca; Privitera, Gaetano; Romano Spica, Vincenzo; Sembeni, Silvia; Spagnolo, Anna Maria; Tardivo, Stefano; Torre, Ida; Valeriani, Federica; Albertini, Roberto; Pasquarella, Cesira

    2017-06-22

    Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis(®)μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis(®)μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis(®)μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis(®)μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations.

  4. Detection of Mycoplasma gallisepticum antibodies in turkey blood samples by ELISA and by the slide agglutination and haemagglutination inhibition tests.

    Science.gov (United States)

    Kaszanyitzky, E; Czifra, G; Stipkovits, L

    1994-01-01

    Comparative examination of a total of 1,030 blood samples from six turkey flocks of three Eastern Hungarian turkey farms was performed by the conventional haemagglutination inhibition (HI) and slide agglutination (SA) tests and by a competitive ELISA visualizing the inhibition by a positive test serum of the reaction between a monoclonal antibody and the specific epitope of Mycoplasma gallisepticum recognized by it. All the three tests detected the flocks which were certainly infected. The highest rate of positivity (93% of the samples tested) was revealed by the ELISA. By SA and HI the positivity rate was 56% and 55%, respectively. Thirty-five per cent of the positive blood samples reacted in all three tests, 17% of them only by ELISA and HI, another 17% only by ELISA and SA, while 3% only by SA and HI. In the case of positive flocks first the SA test and ELISA, then the HI test and ELISA give parallel results.

  5. A comparison of commercially available peanut ELISA test kits on the analysis of samples of dark and milk chocolate.

    Science.gov (United States)

    Hurst, W Jeffre; Krout, Earl R; Burks, Wesley R

    2002-01-01

    Reactions to peanut proteins by certain sensitive members of the population can result in dramatic and potentially catastrophic consequences. While peanut is not the only food known to cause allergies, it is the one that is most closely monitored. To address concerns related to peanut in food products, four commercial test kits have been developed to quantitatively analyze for peanut protein in finished products. This manuscript describes a study undertaken to compare these kits on reference samples of dark and milk chocolate containing known amounts of peanut. The results are mixed with the data suggesting that all kits were suitable for qualitative screening but were not suitable for general quantitative assays.

  6. Performance of the Liaison XL Murex HIV Ab/Ag Test on Clinical Samples Representing Current Epidemic HIV Variants

    OpenAIRE

    Lemee, Véronique; Leoz, Marie; Etienne, Manuel; De Oliveira, Fabienne; Plantier, Jean-Christophe

    2014-01-01

    Screening for HIV infection has improved since the first immunoassays. Today, diagnosis of HIV infection can be performed with fourth-generation tests that track both the patient's antibodies and HIV antigen. The objective of this study was to evaluate the clinical sensitivity and specificity of the new DiaSorin Liaison XL Murex HIV Ab/Ag assay compared to another fourth-generation assay, the Abbott Architect HIV Ag/Ab Combo kit. This work was performed on a large panel of 900 samples, includ...

  7. Factors contributing to variability of quantitative viral PCR results in proficiency testing samples: a multivariate analysis.

    Science.gov (United States)

    Hayden, R T; Yan, X; Wick, M T; Rodriguez, A B; Xiong, X; Ginocchio, C C; Mitchell, M J; Caliendo, A M

    2012-02-01

    While viral load testing has gained widespread acceptance, a primary limitation remains the variability of results, particularly between different laboratories. While some work has demonstrated the importance of standardized quantitative control material in reducing this variability, little has been done to explore other important factors in the molecular amplification process. Results of 185 laboratories enrolled in the College of American Pathologists (CAP) 2009 viral load proficiency testing (PT) survey (VLS) were examined. This included 165 labs (89.2%) testing for cytomegalovirus (CMV), 99 (53.5%) for Epstein-Barr virus (EBV), and 64 (34.6%) for BK virus (BKV). At the time of PT, laboratories were asked a series of questions to characterize their testing methods. The responses to these questions were correlated to mean viral load (MVL) and result variability (RV). Contribution of individual factors to RV was estimated through analysis of variance (ANOVA) modeling and the use of backward selection of factors to fit those models. Selection of the quantitative calibrator, commercially prepared primers and probes, and amplification target gene were found most prominently associated with changes in MVL or RV for one or more of the viruses studied. Commercially prepared primers and probes and amplification target gene made the largest contribution to overall variability. Factors contributing to MVL and RV differed among viruses, as did relative contribution of each factor to overall variability. The marked variability seen in clinical quantitative viral load results is associated with multiple aspects of molecular testing design and performance. The reduction of such variability will require a multifaceted approach to improve the accuracy, reliability, and clinical utility of these important tests.

  8. A Short-Term, Prospective Test of the Interpersonal-Psychological Theory of Suicidal Ideation in an Adolescent Clinical Sample.

    Science.gov (United States)

    Miller, Adam Bryant; Esposito-Smythers, Christianne; Leichtweis, Richard N

    2016-06-01

    The present prospective study tested a portion of the interpersonal-psychological theory of suicide (IPTS) in an adolescent clinical sample. Participants were 143 adolescents consecutively admitted to a partial hospitalization program who completed assessments at intake and discharge from the program. Results partially supported the IPTS and suggest that (1) perceived burdensomeness may be an important socially based cognition for understanding concurrent risk for suicidal ideation (SI); (2) thwarted belongingness affects depression symptom severity over time, which indirectly predicts SI over a short follow-up time frame; and (3) the IPTS constructs may function differently in a high-risk clinical adolescent sample, compared to adults, although findings are preliminary. © 2015 The American Association of Suicidology.

  9. Correlation between Positive Rate and Number of Biopsy Samples on Urease Test in Childhood Helicobacter pylori Infection

    Science.gov (United States)

    Seo, Ji-Hyun; Park, Ji Sook; Yeom, Jung Sook; Lim, Jae-Young; Park, Chan-Hoo; Woo, Hyang-Ok; Baik, Seung-Chul; Lee, Woo-Kon; Cho, Myung-Je; Rhee, Kwang-Ho

    2014-01-01

    To identify the correlation between the number of gastric biopsy samples and the positive rate, we compared the results of urease test using one and three biopsy samples from each 255 children who underwent gastroduodenoscopy at Gyeongsang National University Hospital. The children were divided into three age groups: 0-4, 5-9, and 10-15 yr. The gastric endoscopic biopsies were subjected to the urease test. That is, one and three gastric antral biopsy samples were collected from the same child. The results of urease test were classified into three grades: Grade 0 (no change), 1 (6-24 hr), 2 (1-6 hr), and 3 (<1 hr). The positive rate of urease test was increased by the age with no respect to the number of gastric biopsy samples (one biopsy P = 0.001, three biopsy P < 0.001). The positive rate of the urease test was higher on three biopsy samples as compared with one biopsy sample (P < 0.001). The difference between one and three biopsy samples was higher in the children aged 0-9 yr. Our results indicate that the urease test might be a more accurate diagnostic modality when it is performed on three or more biopsy samples in children. PMID:24431913

  10. Review: Diagnostic accuracy of PCR-based detection tests for Helicobacter Pylori in stool samples.

    Science.gov (United States)

    Khadangi, Fatemeh; Yassi, Maryam; Kerachian, Mohammad Amin

    2017-12-01

    Although different methods have been established to detect Helicobacter pylori (H. pylori) infection, identifying infected patients is an ongoing challenge. The aim of this meta-analysis was to provide pooled diagnostic accuracy measures for stool PCR test in the diagnosis of H. pylori infection. In this study, a systematic review and meta-analysis were carried out on various sources, including MEDLINE, Web of Sciences, and the Cochrane Library from April 1, 1999, to May 1, 2016. This meta-analysis adheres to the guidelines provided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses report (PRISMA Statement). The clinical value of DNA stool PCR test was based on the pooled false positive, false negative, true positive, and true negative of different genes. Twenty-six of 328 studies identified met the eligibility criteria. Stool PCR test had a performance of 71% (95% CI: 68-73) sensitivity, 96% (95% CI: 94-97) specificity, and 65.6 (95% CI: 30.2-142.5) diagnostic odds ratio (DOR) in diagnosis of H. pylori. The DOR of genes which showed the highest performance of stool PCR tests was as follows: 23S rRNA 152.5 (95% CI: 55.5-418.9), 16S rRNA 67.9 (95%CI: 6.4-714.3), and glmM 68.1 (95%CI: 20.1-231.7). The sensitivity and specificity of stool PCR test are relatively in the same spectrum of other diagnostic methods for the detection of H. pylori infection. In descending order of significance, the most diagnostic candidate genes using PCR detection were 23S rRNA, 16S rRNA, and glmM. PCR for 23S rRNA gene which has the highest performance could be applicable to detect H. pylori infection. © 2017 John Wiley & Sons Ltd.

  11. STUDY ON OXYTETRACYCLINE RESIDUES IN COW’S MILK SAMPLES COLLECTED IN TETOVO, MACEDONIA FROM 2012 TO 2013

    OpenAIRE

    Kamberi, Mensur; Sulaj, Kapllan

    2014-01-01

    The objective of this study was to determine the oxytetracycline residues in cow’s milk collected in farms of Tetovo in Macedonia. The cow’s milk samples produced in this area are controlled applying qualitative analytical tests for oxitetracycline residues in 262 milk samples through specific ELISA test. After this control positive milk samples were kept in freezing conditions to be analyzed by high performance liquid chromatography (HPLC) method in order to perform qualitative evaluation of...

  12. Clinical trials with nested subgroups: Analysis, sample size determination and internal pilot studies.

    Science.gov (United States)

    Placzek, Marius; Friede, Tim

    2017-01-01

    The importance of subgroup analyses has been increasing due to a growing interest in personalized medicine and targeted therapies. Considering designs with multiple nested subgroups and a continuous endpoint, we develop methods for the analysis and sample size determination. First, we consider the joint distribution of standardized test statistics that correspond to each (sub)population. We derive multivariate exact distributions where possible, providing approximations otherwise. Based on these results, we present sample size calculation procedures. Uncertainties about nuisance parameters which are needed for sample size calculations make the study prone to misspecifications. We discuss how a sample size review can be performed in order to make the study more robust. To this end, we implement an internal pilot study design where the variances and prevalences of the subgroups are reestimated in a blinded fashion and the sample size is recalculated accordingly. Simulations show that the procedures presented here do not inflate the type I error significantly and maintain the prespecified power as long as the sample size of the smallest subgroup is not too small. We pay special attention to the case of small sample sizes and attain a lower boundary for the size of the internal pilot study.

  13. Sampling pig farms at the abattoir in a cross-sectional study − Evaluation of a sampling method

    DEFF Research Database (Denmark)

    Birkegård, Anna Camilla; Hisham Beshara Halasa, Tariq; Toft, Nils

    2017-01-01

    A cross-sectional study design is relatively inexpensive, fast and easy to conduct when compared to other study designs. Careful planning is essential to obtaining a representative sample of the population, and the recommended approach is to use simple random sampling from an exhaustive list of u...

  14. Influence of Homogenization of Clay Batch for Laboratory Test on the Structure of the Ceramic Samples

    Directory of Open Access Journals (Sweden)

    Toropkov Nikita

    2016-01-01

    Full Text Available In this paper, we study the chemical and mineralogical composition of the Krasnoyarsk Kray clay used in the production of coarse ceramics. It is found that the fire –strength depends of method of preparation of clay paste. It is shown that the forced dissolution of the raw clay material effectively homogenizes clay paste. As a result, strength of the samples increased during firing. It is also justified by the influence of their mineralogical composition and there method of the preparation. It is proved that conditions of preparation and mineralogical composition affect equally.

  15. A comparative study of general intelligence in Spanish and Moroccan samples.

    Science.gov (United States)

    Diaz, Amelia; Sellami, Khadija; Infanzón, Eugenia; Lanzón, Teresa; Lynn, Richard

    2012-07-01

    The aim of this study is to fill a gap in intelligence research by presenting data for the average IQ in Morocco and for a comparable sample in Spain. Adult samples were administered the Raven Standard Progressive Matrices (SPM) (Raven, Court, & Raven, 2001) and scored for the total test and for the three sub-factors of gestalt continuation, verbal-analytical reasoning and visuospatial ability identified by Lynn, Allik, and Irwing (2004). The total test and the three factors have shown satisfactory reliability. Our results for the Moroccan sample show significant relationship between general intelligence factor, gestalt continuation and visuospatial ability with education level and income. Conversely, these variables have been shown to be independent for the Spanish sample. This sample obtained significantly higher scores for the four factors assessed than the Moroccan one. These differences have been found also comparing samples with the same education levels. Finally, the errors percentage for Moroccans has been higher than for Spaniards in all the items, suggesting that the level of difficulty was higher for the Moroccan sample.

  16. TRACKING PYRETHROID TOXICITY IN SURFACE WATER SAMPLES: EXPOSURE DYNAMICS AND TOXICITY IDENTIFICATION TOOLS FOR LABORATORY TESTS WITH HYALELLA AZTECA (AMPHIPODA).

    Science.gov (United States)

    Deanovic, Linda A; Stillway, Marie; Hammock, Bruce G; Fong, Stephanie; Werner, Inge

    2017-09-09

    Pyrethroid insecticides are commonly used in pest control and are present at toxic concentrations in surface waters of agricultural and urban areas worldwide. Monitoring is challenging due to their high hydrophobicity and low toxicity thresholds, which often fall below the detection limits of analytical methods. Standard daphnid bioassays used in surface water monitoring are not sensitive enough to protect more susceptible invertebrate species such as the amphipod, Hyalella azteca, and chemical loss during toxicity testing is of concern. In this study, we quantified toxicity loss during storage and testing, using both natural and synthetic water, and present a tool to enhance toxic signal strength for improved sensitivity of H. azteca toxicity tests. The average half-life during storage in LDPE cubitainers at 4°C of five pyrethroids (permethrin, bifenthrin, lambda-cyhalothrin, cyfluthrin, esfenvalerate) and one organophosphate (chlorpyrifos; used as reference) was 1.4 d, and piperonyl butoxide (PBO) proved an effective tool to potentiate toxicity. We conclude that toxicity tests on ambient water samples containing these hydrophobic insecticides are likely to underestimate toxicity present in the field, and mimic short pulse rather than continuous exposures. Where these chemicals are of concern, the addition of PBO during testing can yield valuable information on their presence or absence. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. A Small Sample Study of Traditional and Online Courses with Sample Selection Adjustment

    Science.gov (United States)

    Anstine, Jeff; Skidmore, Mark

    2005-01-01

    In this research, the authors examine whether M.B.A. students at a regional, comprehensive university who take only online courses learn as much as students taking identical courses in the traditional, face-to-face format. A simple comparison of test scores indicates that the amount of learning is similar in the two formats. However, when other…

  18. Students’ ability in science: Results from a test development study

    Directory of Open Access Journals (Sweden)

    Cigdem Akkanat

    2017-03-01

    Full Text Available Student’s ability to use and manipulate scientific concepts has been widely explored; however there is still a need to define the characteristics and nature of science ability. Also, the tests and performance scales that require minimal conceptual knowledge to measure this ability are relatively less common. The aim of this study was to develop an objective measure of science ability of gifted middle school students. In order to assess this ability, Science Ability Test Battery was developed by the researchers. The test battery was divided into two sub scales containing; a multiple choice questions achievement test (Science Ability Test and a performance assessment (Science Performance Test. The initial Science Ability Test consisted of 23 multiple choice items with one correct answer that required students to use science process skills and reasoning. In the study, stratified sampling was used. The test was administered to 280 middle school students in Turkey and the missing data from 26 students were excluded. In order to obtain a proof of content validity, the researchers elicited feedback from five experts in the field of science education and gifted education and necessary corrections were made in accordance of their views and suggestions. This study will be followed by another research to further analyse validity and reliability of the test.

  19. Pilot evaluation of the Computer-Based Assessment for Sampling Personal Characteristics test.

    Science.gov (United States)

    Shipper, Edward S; Mazer, Laura M; Merrell, Sylvia Bereknyei; Lin, Dana T; Lau, James N; Melcher, Marc L

    2017-07-01

    High attrition rates hint at deficiencies in the resident selection process. The evaluation of personal characteristics representative of success is difficult. Here, we evaluate a novel tool for assessing personal characteristics. To evaluate feasibility, we used an anonymous voluntary survey questionnaire offered to study participants before and after contact with the CASPer test. To evaluate the CASPer test as a predictor of success, we compared CASPer test assessments of personal characteristics versus traditional faculty assessment of personal characteristics with applicant rank list position. All applicants (n = 77) attending an in-person interview for general surgery residency, and all faculty interviewers (n = 34) who reviewed these applications were invited to participate. Among applicants, 84.4% of respondents (65 of 77) reported that a requirement to complete the CASPer test would have no bearing or would make them more likely to apply to the program (mean = 3.30, standard deviation = 0.96). Among the faculty, 62.5% respondents (10 of 16) reported that the same condition would have no bearing or would make applicants more likely to apply to the program (mean = 3.19, standard deviation = 1.33). The Spearman's rank-order correlation coefficients for the relationships between traditional faculty assessment of personal characteristics and applicant rank list position, and novel CASPer assessment of personal characteristics and applicant rank list position, were -0.45 (P = 0.033) and -0.41 (P = 0.055), respectively. The CASPer test may be feasibly implemented as component of the resident selection process, with the potential to predict applicant rank list position and improve the general surgery resident selection process. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Study population, questionnaire, data management and sample description

    Directory of Open Access Journals (Sweden)

    Chiara de Waure

    2015-06-01

    Full Text Available INTRODUCTION: This article describes methodological issues of the "Sportello Salute Giovani" project ("Youth Health Information Desk", a multicenter study aimed at assessing the health status and attitudes and behaviours of university students in Italy. MATERIALS AND METHODS: The questionnaire used to carry out the study was adapted from the Italian health behaviours in school-aged children (HBSC project and consisted of 93 items addressing: demographics; nutritional habits and status; physical activity; lifestyles; reproductive and preconception health; health and satisfaction of life; attitudes and behaviours toward academic study and new technologies. The questionnaire was administered to a pool of 12 000 students from 18 to 30 years of age who voluntary decided to participate during classes held at different Italian faculties or at the three "Sportello Salute Giovani" centers which were established in the three sites of the Università Cattolica del Sacro Cuore (Catholic University of the Sacred Heart of Rome. RESULTS: The final study sample was composed by 8516 university students. The mean age of responders was 22.2 (Standard Deviation 2.0 and 5702 (67.0% were females. According to the distribution in age classes, 3601 (43.3% belonged to the 18-21 one, 3796 (44.5% to the 22-24 class and 1019 (12.2% to the 25-30 class. With respect to socio-economic status, data were available for 8410 responders and showed that 50.3% of students belonged to the middle class. DISCUSSION: The project took into consideration a large number of individuals from different regions of the country and therefore may be considered representative of the general population of Italian university students. Furthermore, it is the first to address, at the same time, several issues, in particular attitudes and behaviours toward health, in Italian university students. CONCLUSION: The analysis of data from such a large sample of university students sets the basis for

  1. Single versus double testing of meat-juice samples for Salmonella antibodies, in the Danish pig-herd surveillance programme

    DEFF Research Database (Denmark)

    Ekeroth, Lars; Alban, Lis; Feld, Niels Christian

    2003-01-01

    In Denmark, a national serological surveillance-and-control programme for Salmonella in pigs has been in operation since 1995. The programme is based on the Danish mix-ELISA and uses double testing (two ELISA-wells used per sample) of meat-juice samples taken in relation to slaughter. All herds...... are classified monthly into one of the three levels; the classification is based on the percentage of positive serological results in the previous 3 months. In connection with evaluation of the programme in 2001, we investigated whether single testing (testing in one well only) could be expected...... to be sufficiently precise compared to double testing. Data from the year 2000 were used, and mathematical modelling. Single testing was simulated by randomised selection of one of the two results in the double testing. A slight increase in the prevalence of Salmonella-positive samples (1.02-1.09 times more through...

  2. Nonparametric relevance-shifted multiple testing procedures for the analysis of high-dimensional multivariate data with small sample sizes

    Directory of Open Access Journals (Sweden)

    Kropf Siegfried

    2008-01-01

    Full Text Available Abstract Background In many research areas it is necessary to find differences between treatment groups with several variables. For example, studies of microarray data seek to find a significant difference in location parameters from zero or one for ratios thereof for each variable. However, in some studies a significant deviation of the difference in locations from zero (or 1 in terms of the ratio is biologically meaningless. A relevant difference or ratio is sought in such cases. Results This article addresses the use of relevance-shifted tests on ratios for a multivariate parallel two-sample group design. Two empirical procedures are proposed which embed the relevance-shifted test on ratios. As both procedures test a hypothesis for each variable, the resulting multiple testing problem has to be considered. Hence, the procedures include a multiplicity correction. Both procedures are extensions of available procedures for point null hypotheses achieving exact control of the familywise error rate. Whereas the shift of the null hypothesis alone would give straight-forward solutions, the problems that are the reason for the empirical considerations discussed here arise by the fact that the shift is considered in both directions and the whole parameter space in between these two limits has to be accepted as null hypothesis. Conclusion The first algorithm to be discussed uses a permutation algorithm, and is appropriate for designs with a moderately large number of observations. However, many experiments have limited sample sizes. Then the second procedure might be more appropriate, where multiplicity is corrected according to a concept of data-driven order of hypotheses.

  3. Physical work environment: testing an expanded model of job satisfaction in a sample of registered nurses.

    Science.gov (United States)

    Djukic, Maja; Kovner, Christine; Budin, Wendy C; Norman, Robert

    2010-01-01

    The impact of personal, organizational, and economic factors on nurses' job satisfaction have been studied extensively, but few studies exist in which the effects of physical work environment--including perceptions of architectural, interior design, and ambient features on job satisfaction-are examined. The purpose of this study was to examine the effect of perceived physical work environment on job satisfaction, adjusting for multiple personal, organizational, and economic determinants of job satisfaction. A cross-sectional, predictive design and a Web-based survey instrument were used to collect data from staff registered nurses in a large metropolitan hospital. The survey included 34 questions about multiple job satisfaction determinants, including 18 Likert-type measures with established good validity (comparative fit index = .97, Tucker-Lewis index = .98, root mean square error of approximation = .06) and reliability (r ≥ .70). A response rate of 48.5% resulted in a sample of 362, with 80% power to detect a medium effect of perceived physical environment on job satisfaction. On average, nurses had negative perceptions of physical work environment (M = 2.9, SD = 2.2). Although physical environment was related positively to job satisfaction (r =.256, p = .01) in bivariate analysis, in ordered probit regression, no effect of physical work environment on job satisfaction was found. In future studies, this relationship should be examined in larger and more representative samples of nurses. Qualitative methods should be used to explore how negatively perceived physical work environment impacts nurses. Rebuilding of U.S. hospitals, with a planned investment of $200 billion without considering how physical environment contributes to nurse work outcomes, threatens to exacerbate organizational nurse turnover.

  4. Comparison of the Abbott RealTime High Risk HPV test and the Roche cobas 4800 HPV test using urine samples.

    Science.gov (United States)

    Lim, Myong Cheol; Lee, Do-Hoon; Hwang, Sang-Hyun; Hwang, Na Rae; Lee, Bomyee; Shin, Hye Young; Jun, Jae Kwan; Yoo, Chong Woo; Lee, Dong Ock; Seo, Sang-Soo; Park, Sang-Yoon; Joo, Jungnam

    2017-05-01

    Human papillomavirus (HPV) testing based on cervical samples is important for use in cervical cancer screening. However, cervical sampling is invasive. Therefore, non-invasive methods for detecting HPV, such as urine samples, are needed. For HPV detection in urine samples, two real-time PCR (RQ-PCR) tests, Roche cobas 4800 test (Roche_HPV; Roche Molecular Diagnostics) and Abbott RealTime High Risk HPV test (Abbott_HPV; Abbott Laboratories) were compared to standard cervical samples. The performance of Roche_HPV and Abbott_HPV for HPV detection was evaluated at the National Cancer Center using 100 paired cervical and urine samples. The tests were also compared using urine samples stored at various temperatures and for a range of durations. The overall agreement between the Roche_HPV and Abbott_HPV tests using urine samples for any hrHPV type was substantial (86.0% with a kappa value of 0.7173), and that for HPV 16/18 was nearly perfect (99.0% with a kappa value of 0.9668). The relative sensitivities (based on cervical samples) for HPV 16/18 detection using Roche_HPV and Abbott_HPV with urine samples were 79.2% (95% CI; 57.9-92.9%) and 81.8% (95% CI; 59.7-94.8%), respectively. When the cut-off CT value for Abbott_HPV was extended to 40 for urine samples, the relative sensitivity of Abbott_HPV increased to 91.7% from 81.8% for HPV16/18 detection and to 87.0% from 68.5% for other hrHPV detection. The specificity was not affected by the change in the CT threshold. Roche_HPV and Abbott_HPV showed high concordance. However, HPV DNA detection using urine samples was inferior to HPV DNA detection using cervical samples. Interestingly, when the cut-off CT value was set to 40, Abbott_HPV using urine samples showed high sensitivity and specificity, comparable to those obtained using cervical samples. Fully automated DNA extraction and detection systems, such as Roche_HPV and Abbott_HPV, could reduce the variability in HPV detection and accelerate the standardization of HPV

  5. Study of interaction between croscarmellose and escitalopram during sample preparation.

    Science.gov (United States)

    Larsen, Jesper; Melander, Claes

    2012-10-01

    During routine analysis of an escitalopram tablet formulation, it was seen that there was a systematic deviation between content uniformity (CU - one tablet analysis) and assay analysis (ten pooled tablets). In the presence of the excipients from the tablet, it was found that the extraction of the active pharmaceutical ingredient (API) was incomplete. It was shown that the commonly used tablet disintegrant croscarmellose sodium (crosslinked carboxy-methyl cellulose) had a significant interaction with escitalopram. This was later found to be the explanation for the lower extraction during assay testing. Under normal conditions, the extraction took place in acidic medium which caused protonation of the amine and thereby the interaction of charged species in solution. The interaction of API was studied further with pure croscarmellose and the entire tablet matrix. A range of conditions was considered, including altering extraction volumes, organic solvents, pH of the extraction solvent, and addition of competitive binder in various concentrations. It was seen that arginine was the most effective cationic competitive binder of those tested and that adding it at a suitable concentration level could significantly improve the analytical methods. In the present case, an improvement in recovery was from 98.5% to almost 100% was achieved.

  6. Test Sample for the Spatially Resolved Quantification of Illicit Drugs on Fingerprints Using Imaging Mass Spectrometry.

    Science.gov (United States)

    Muramoto, Shin; Forbes, Thomas P; van Asten, Arian C; Gillen, Greg

    2015-01-01

    A novel test sample for the spatially resolved quantification of illicit drugs on the surface of a fingerprint using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and desorption electrospray ionization mass spectrometry (DESI-MS) was demonstrated. Calibration curves relating the signal intensity to the amount of drug deposited on the surface were generated from inkjet-printed arrays of cocaine, methamphetamine, and heroin with a deposited-mass ranging nominally from 10 pg to 50 ng per spot. These curves were used to construct concentration maps that visualized the spatial distribution of the drugs on top of a fingerprint, as well as being able to quantify the amount of drugs in a given area within the map. For the drugs on the fingerprint on silicon, ToF-SIMS showed great success, as it was able to generate concentration maps of all three drugs. On the fingerprint on paper, only the concentration map of cocaine could be constructed using ToF-SIMS and DESI-MS, as the signals of methamphetamine and heroin were completely suppressed by matrix and substrate effects. Spatially resolved quantification of illicit drugs using imaging mass spectrometry is possible, but the choice of substrates could significantly affect the results.

  7. 101-SY waste sample speed of sound/rheology testing for sonic probe program

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, N.S.

    1994-07-25

    One problem faced in the clean-up operation at Hanford is that a number of radioactive waste storage tanks are experiencing a periodic buildup and release of potentially explosive gases. The best known example is Tank 241-SY-101 (commonly referred to as 101-SY) in which hydrogen gas periodically built up within the waste to the point that increased buoyancy caused a roll-over event, in which the gas was suddenly released in potentially explosive concentrations (if an ignition source were present). The sonic probe concept is to generate acoustic vibrations in the 101-SY tank waste at nominally 100 Hz, with sufficient amplitude to cause the controlled release of hydrogen bubbles trapped in the waste. The sonic probe may provide a potentially cost-effective alternative to large mixer pumps now used for hydrogen mitigation purposes. Two important parameters needed to determine sonic probe effectiveness and design are the speed of sound and yield stress of the tank waste. Tests to determine these parameters in a 240 ml sample of 101-SY waste (obtained near the tank bottom) were performed, and the results are reported.

  8. Improving toxicity assessment of pesticide mixtures: the use of polar passive sampling devices extracts in microalgae toxicity tests

    Directory of Open Access Journals (Sweden)

    Sandra KIM TIAM

    2016-09-01

    Full Text Available Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively aimed i at characterizing the toxic potential of waters using dose-response curves, and ii at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed.

  9. Improving Toxicity Assessment of Pesticide Mixtures: The Use of Polar Passive Sampling Devices Extracts in Microalgae Toxicity Tests.

    Science.gov (United States)

    Kim Tiam, Sandra; Fauvelle, Vincent; Morin, Soizic; Mazzella, Nicolas

    2016-01-01

    Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS) and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD) extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively, aimed (i) at characterizing the "toxic potential" of waters using dose-response curves, and (ii) at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed.

  10. Burden of tuberculosis in intensive care units in Cape Town, South Africa, and assessment of the accuracy and effect on patient outcomes of the Xpert MTB/RIF test on tracheal aspirate samples for diagnosis of pulmonary tuberculosis: a prospective burden of disease study with a nested randomised controlled trial.

    Science.gov (United States)

    Calligaro, Gregory L; Theron, Grant; Khalfey, Hoosain; Peter, Jonathan; Meldau, Richard; Matinyenya, Brian; Davids, Malika; Smith, Liezel; Pooran, Anil; Lesosky, Maia; Esmail, Aliasgar; Miller, Malcolm G; Piercy, Jenna; Michell, Lancelot; Dawson, Rodney; Raine, Richard I; Joubert, Ivan; Dheda, Keertan

    2015-08-01

    There are few prospective data about the incidence and mortality associated with pulmonary tuberculosis in intensive care units (ICUs), and none on the accuracy and clinical effect of the Xpert-MTB/RIF assay in this setting. We aimed to measure the frequency of culture-positive tuberculosis in ICUs in Cape Town, South Africa and to assess the performance and effect on patient outcomes of Xpert MTB/RIF versus smear microscopy for diagnosis of tuberculosis. We did a prospective burden of disease study with a randomised controlled substudy at the ICUs of four hospitals in Cape Town. Mechanically ventilated adults (≥18 years) with suspected pulmonary tuberculosis admitted between Aug 1, 2010, and July 31, 2013 (irrespective of the reason for admission), were prospectively investigated by culture, and by Xpert-MTB/RIF testing or smear microscopy, of tracheal aspirate samples. In the substudy, patients were randomly assigned (1:1), via a computer-generated allocation list, to smear microscopy or Xpert MTB/RIF. Participants, caregivers, and outcome assessors were not masked to group assignment. Only the laboratory staff were blinded to the clinical details of the participants. In November, 2012, Xpert MTB/RIF was adopted as the initial diagnostic test for respiratory samples in Western Cape province. Thereafter, patients received Xpert MTB/MIF and culture as standard of care. For the whole study cohort, the primary outcome was the frequency of bacteriologically confirmed tuberculosis. The primary endpoint of the randomised substudy was the proportion of culture-positive patients on treatment at 48 h after enrolment. The randomised substudy is registered with ClinicalTrials.gov, number NCT01530568. We investigated 341 patients for suspected pulmonary tuberculosis out of a total of 2309 ICU admissions. 46 (15%) of 317 patients included in the final analysis had a positive test for tuberculosis (Xpert MTB/RIF or culture). Culture-positive patients who failed to initiate

  11. Sampling plans for lightning surges test program. Final report, May 1976--January 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-03-01

    Results are presented of a study undertaken to determine how to measure and evaluate lightning-induced surges on power distribution lines. The study centered on the following basic tasks: prediction of ligntning phenomena; selection and characterization of instrument placement sites; determination of appropriate number of instruments; determination of instrument storage and data collection requirements; and recommendations for future efforts. It was concluded that 400 lightning surge recorders are needed for accummulating basic test data; 250 additional instruments are recommended for obtaining supplementary data; the instruments should be placed throughout the US with careful control of site selection and instrument installation; each instrument should be able to store one year's data; and this proposed field study is only the first step in achieving an understanding of the lightning protection cost-benefit problem. (LCL)

  12. Adaptive autonomous sampling toward the study of microbial carbon and energy fluxes in a dynamic estuary

    Science.gov (United States)

    Herfort, L.; Seaton, C. M.; Wilkin, M.; Baptista, A. M.; Roman, B.; Preston, C. M.; Scholin, C. A.; Melançon, C.; Simon, H. M.

    2013-12-01

    An autonomous microbial sampling device was integrated with a long-term (endurance) environmental sensor system to investigate variation in microbial composition and activities related to complex estuarine dynamics. This integration was a part of ongoing efforts in the Center for Coastal Margin Observation and Prediction (CMOP) to study estuarine carbon and nitrogen cycling using an observation and prediction system (SATURN, http://www.stccmop.org/saturn) as foundational infrastructure. The two endurance stations fitted with physical and biogeochemical sensors that were used in this study are located in the SATURN observation network. The microbial sampler is the Environmental Sample Processor (ESP), a commercially available electromechanical/fluidic system designed for automated collection, preservation and in situ analyses of marine water samples. The primary goal of the integration was to demonstrate that the ESP, developed for sampling of pelagic oceanic environments, could be successfully deployed for autonomous sample acquisition in the highly dynamic and turbid Columbia River estuary. The ability of the ESP to collect material at both pre-determined times and automatically in response to local conditions was tested. Pre-designated samples were acquired at specific times to capture variability in the tidal cycle. Autonomous, adaptive sampling was triggered when conditions associated with specific water masses were detected in real-time by the SATURN station's sensors and then communicated to the ESP via the station computer to initiate sample collection. Triggering criteria were based on our understanding of estuary dynamics, as provided by the analysis of extensive archives of high-resolution, long-term SATURN observations and simulations. In this manner, we used the ESP to selectively sample various microbial consortia in the estuary to facilitate the study of ephemeral microbial-driven processes. For example, during the summer of 2013 the adaptive sampling

  13. Tank vapor sampling and analysis data package for tank 241-C-106 waste retrieval sluicing system process test phase III

    Energy Technology Data Exchange (ETDEWEB)

    LOCKREM, L.L.

    1999-08-13

    This data package presents sampling data and analytical results from the March 28, 1999, vapor sampling of Hanford Site single-shell tank 241-C-106 during active sluicing. Samples were obtained from the 296-C-006 ventilation system stack and ambient air at several locations. Characterization Project Operations (CPO) was responsible for the collection of all SUMMATM canister samples. The Special Analytical Support (SAS) vapor team was responsible for the collection of all triple sorbent trap (TST), sorbent tube train (STT), polyurethane foam (PUF), and particulate filter samples collected at the 296-C-006 stack. The SAS vapor team used the non-electrical vapor sampling (NEVS) system to collect samples of the air, gases, and vapors from the 296-C-006 stack. The SAS vapor team collected and analyzed these samples for Lockheed Martin Hanford Corporation (LMHC) and Tank Waste Remediation System (TWRS) in accordance with the sampling and analytical requirements specified in the Waste Retrieval Sluicing System Vapor Sampling and Analysis Plan (SAP) for Evaluation of Organic Emissions, Process Test Phase III, HNF-4212, Rev. 0-A, (LMHC, 1999). All samples were stored in a secured Radioactive Materials Area (RMA) until the samples were radiologically released and received by SAS for analysis. The Waste Sampling and Characterization Facility (WSCF) performed the radiological analyses. The samples were received on April 5, 1999.

  14. The Aggression Questionnaire: a validation study in student samples.

    Science.gov (United States)

    García-León, Ana; Reyes, Gustavo A; Vila, Jaime; Pérez, Nieves; Robles, Humbelina; Ramos, Manuel M

    2002-05-01

    The goal of this study was to examine the psychometric properties of the Aggression Questionnaire (AQ) in Spain. The AQ is a 29-item instrument designed to measure the different dimensions of the hostility/anger/aggression construct. It consists of 4 subscales that assess: (a) anger, (b) hostility, (c) verbal aggression, and (d) physical aggression. In Study 1, reliability, construct validity, and convergent validity were evaluated in a group of 384 male and female university students. Test-retest reliability was evaluated using a group of 154 male and female university students. The results of the factor analysis were similar to the scale structure claimed for this instrument. The subscales also showed internal consistency and stability over time. The AQ and its subscales were also compared with the scales and subscales of the Spielberger State-Trait Anger Expression Inventory (STAXI), the Cook-Medley Hostility Scale (Ho), the Buss-Durkee Hostility Inventory (BDHI), and the Jenkins Activity Survey-Form H (JASE-H). The results show that the AQ evaluates some aspects of anger, such as Anger-Trait and Anger-Out, rather than other elements, such as Anger-In or Anger-State. In Study 2, two new male groups were used to evaluate the criterion validity of the AQ: 57 prison inmates and 93 university students, finding that this instrument discriminated between the scores obtained by common offenders and university students.

  15. An Examination of the Test-Retest Reliability of the ACE-SQ in a Sample of College Athletes.

    Science.gov (United States)

    Zanotti, Danielle C; Kaier, Emily; Vanasse, Renee; Davis, Joanne L; Strunk, Kathleen C; Cromer, Lisa DeMarni

    2017-10-09

    The Adverse Childhood Experiences (ACE) study is one of the largest studies ever conducted that has examined the relationship of childhood abuse, neglect, and family dysfunction to subsequent health and well-being later in life. Questions from the ACE study evolved into the ACE Study Questionnaire, a measure used for assessing individuals' self-reported experiences of childhood adversity. The ACE measure is widely available and the Centers for Disease Control and Prevention (CDC) recommends it as a tool for assessing one's lifetime risk of mental and physical health problems and other negative social problems. Despite the extensive dissemination of the ACE Study Questionnaire, to date there has been only one article published about its psychometric properties. The current study examined the test-retest reliability of the ACE-SQ in a sample of nonservice seeking college athletes (N = 141). Time 1 and Time 2 of data collection were approximately one year apart. Pearson's correlations were computed to observe a level of agreement between Time 1 and Time 2 responses. The overall measure yielded a modest test-retest coefficient, r = .71, p < .001. Household dysfunction items demonstrated a higher stability coefficient, r = .65, p < .001 than did abuse and neglect items, r = .52, p < .001. These findings suggest that further research is needed on the psychometric properties of this questionnaire in different age populations. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  16. Outpatient Tinnitus Clinic, Self-Help Web Platform, or Mobile Application to Recruit Tinnitus Study Samples?

    Science.gov (United States)

    Probst, Thomas; Pryss, Rüdiger C; Langguth, Berthold; Spiliopoulou, Myra; Landgrebe, Michael; Vesala, Markku; Harrison, Stephen; Schobel, Johannes; Reichert, Manfred; Stach, Michael; Schlee, Winfried

    2017-01-01

    For understanding the heterogeneity of tinnitus, large samples are required. However, investigations on how samples recruited by different methods differ from each other are lacking. In the present study, three large samples each recruited by different means were compared: N = 5017 individuals registered at a self-help web platform for tinnitus (crowdsourcing platform Tinnitus Talk), N = 867 users of a smart mobile application for tinnitus (crowdsensing platform TrackYourTinnitus), and N = 3786 patients contacting an outpatient tinnitus clinic (Tinnitus Center of the University Hospital Regensburg). The three samples were compared regarding age, gender, and duration of tinnitus (month or years perceiving tinnitus; subjective report) using chi-squared tests. The three samples significantly differed from each other in age, gender and tinnitus duration (p platform were younger, users of the Tinnitus Talk crowdsourcing platform had more often female gender, and users of both newer technologies (crowdsourcing and crowdsensing) had more frequently acute/subacute tinnitus (20 years). The implications of these findings for clinical research are that newer technologies such as crowdsourcing and crowdsensing platforms offer the possibility to reach individuals hard to get in contact with at an outpatient tinnitus clinic. Depending on the aims and the inclusion/exclusion criteria of a given study, different recruiting strategies (clinic and/or newer technologies) offer different advantages and disadvantages. In general, the representativeness of study results might be increased when tinnitus study samples are recruited in the clinic as well as via crowdsourcing and crowdsensing.

  17. Results of Hg speciation testing on DWPF SMECT-4, SMECT-6, and RCT-2 samples

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-02-04

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences, Inc. in Seattle, WA on behalf of the Savannah River Remediation (SRR) Mercury Task Team.i,ii The fifteenth shipment of samples was designated to include Defense Waste Processing Facility (DWPF) Slurry Mix Evaporator Condensate Tank (SMECT) samples from Sludge Receipt and Adjustment Tank (SRAT) Batch 738 and a Recycle Condensate Tank (RCT) sample from SRAT Batch 736. The DWPF sample designations for the three samples analyzed are provided in Table 1. The Batch 738 ‘Baseline’ SMECT sample was taken prior to Precipitate Reactor Feed Tank (PRFT) addition and concentration and therefore, precedes the SMECT-5 sample reported previously. iii The Batch 738 ‘End of SRAT Cycle’ SMECT sample was taken at the conclusion of SRAT operations for this batch (PRFT addition/concentration, acid additions, initial concentration, MCU addition, and steam stripping). Batch 738 experienced a sludge slurry carryover event, which introduced sludge solids to the SMECT that were particularly evident in the SMECT-5 sample, but less evident in the ‘End of SRAT Cycle’ SMECT-6 sample. The Batch 736 ‘After SME’ RCT sample was taken after completion of SMECT transfers at the end of the SME cycle.

  18. A comparative study of sampling techniques for monitoring carcass contamination

    NARCIS (Netherlands)

    Snijders, J.M.A.; Janssen, M.H.W.; Gerats, G.E.; Corstiaensen, G.P.

    1984-01-01

    Four bacteriological sampling techniques i.e. the excision, double swab, agar contract and modified agar contact techniques were compared by sampling pig carcasses before and after chilling. As well as assessing the advantages and disadvantages of the techniques particular attention was paid to

  19. Lessons learned from CIRFT testing on SNF vibration integrity study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jiang, Hao [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce Balkcom [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, Rob L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Scaglione, John M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    A cyclic integrated reversible-bending fatigue tester (CIRFT) was developed to support U.S. NRC and DOE Used Fuel Disposition Campaign studies on high burn-up (HBU) spent nuclear fuel (SNF) transportation during normal conditions of transport (NCT). Two devices were developed; the first CIRFT was successfully installed and operated in the ORNL hot-cells in September 2013. Since hot cell testing commenced several HBU SNF samples from both Zr-4 and M5 clads were investigated. The second CIRFT device was developed in February 2014, and has been used to test clad/fuel surrogate rods (stainless steel with alumina pellet inserts). The second CIRFT machine has also been used for sensor development and test sensitivity analyses, as well as loading boundary condition parameter studies. The lessons learned from CIRFT testing will be presented in this paper.

  20. The Center for Epidemiologic Studies Depression Scale: Factor Validity and Reliability in a French Sample of Adolescents with Intellectual Disability

    Science.gov (United States)

    Maiano, Christophe; Morin, Alexandre J. S.; Begarie, Jerome

    2011-01-01

    The purpose of this study was to test the factor validity and reliability of the Center for Epidemiologic Studies Depression Scale (CES-D) within a sample of adolescents with mild to moderate Intellectual Disability (ID). A total sample of 189 adolescents (121 boys and 68 girls), aged between 12 and 18 years old, with mild to moderate ID were…

  1. Comparison of Unsatisfactory Samples from Conventional Smear versus Liquid-Based Cytology in Uterine Cervical Cancer Screening Test

    Directory of Open Access Journals (Sweden)

    Hoiseon Jeong

    2017-05-01

    Full Text Available Background Cervical cytology for uterine cervical cancer screening has transitioned from conventional smear (CS to liquid-based cytology (LBC, which has many advantages. The aim of this study was to compare the proportion of unsatisfactory specimens from CS versus LBC at multiple institutions including general hospitals and commercial laboratories. Methods Each participating institution provided a minimum of 500 Papanicolaou (Pap test results for analysis. Pap tests were classified according to the participating institution (commercial laboratory or general hospital and the processing method (CS, ThinPrep, SurePath, or CellPrep. The causes of unsatisfactory results were classified as technical problems, scant cellularity, or complete obscuring factors. Results A total of 38,956 Pap test results from eight general hospitals and three commercial laboratories were analyzed. The mean unsatisfactory rate of LBC was significantly lower than that of CS (1.26% and 3.31%, p = .018. In the LBC method, samples from general hospitals had lower unsatisfactory rates than those from commercial laboratories (0.65% vs 2.89%, p = .006. The reasons for unsatisfactory results were heterogeneous in CS. On the other hand, 66.2% of unsatisfactory results in LBC were due to the scant cellularity. Conclusions Unsatisfactory rate of cervical cancer screening test results varies according to the institution and the processing method. LBC has a significantly lower unsatisfactory rate than CS.

  2. Effects of injection speed of test samples on the mouse bioassay for paralytic shellfish poisoning toxins

    Directory of Open Access Journals (Sweden)

    Hodaka Suzuki

    2013-06-01

    Full Text Available The mouse bioassay has been used as the official method for paralytic shellfish poisoning toxins detection in Japan since 1980. However, differences in the results of this assay, when performed by different investigators, have been noted despite the use of the same sample. This study was performed to examine the effect of the injection speed, a hypothetical cause of such differences, on the death time of mice. Speed-controlled injection of the toxin (at 12, 6, 3, and 1.5 mL/min into mice was performed using a syringe pump, and the death times of mice were measured. No statistically significant differences were found among the groups, even between fast injection (5 s and very slow injection (40 s, indicating that the injection speed may not be the crucial factor for this assay.

  3. Quality control in diagnostic molecular pathology in the Netherlands; proficiency testing for patient identification in tissue samples.

    NARCIS (Netherlands)

    Thunnissen, F.B.J.M.; Tilanus, M.G.J.; Ligtenberg, M.J.L.; Nederlof, P.M.; Dinjens, W.N.; Meulemans, E.; Brule, A.J. van den; Noesel, C.J. van; Leeuw, W. de; Schuuring, E.

    2004-01-01

    AIMS: To describe the evolution of proficiency testing for molecular diagnostic pathology with respect to determining unambiguously the patient identity of tissue samples by microsatellite analysis. METHOD: Four rounds of quality control exchanges of samples from different patients were sent with

  4. Differentiation of amphetamine/methamphetamine and other cross-immunoreactive sympathomimetic amines in urine samples by serial dilution testing.

    Science.gov (United States)

    Woodworth, Alison; Saunders, Al N; Koenig, John W; Moyer, Thomas P; Turk, John; Dietzen, Dennis J

    2006-04-01

    Immunoassay-based screening for amphetamines has a variable positive predictive value (PPV) for detecting amphetamine abuse. The lack of immunoassay specificity necessitates confirmatory testing by gas chromatography-mass spectrometry (GC/MS), but the technical complexity and expense of GC/MS limit its availability. Physicians may make decisions regarding patient disposition based on unverified results. In this study we assessed the utility of using dose-response properties to distinguish urine samples containing amphetamines from samples containing cross-immunoreactive species. Urine was supplemented with known concentrations of amphetamine, methamphetamine, methylenedioxymethamphetamine (MDMA), or pseudoephedrine. Using a series of dilutions, we determined the maximum change in rate over the fractional change in concentration for each compound in the Emit II amphetamine/methamphetamine immunoassay. Patient urine samples that screened positive for amphetamines were diluted 1:1, 1:10, and 1:20, and maximum slope estimates within the dynamic assay range were determined. An optimal slope cutoff that differentiated samples containing (meth)amphetamine from those containing cross-reacting species was determined by ROC analysis. The slope of the dose response was largest for amphetamine and methamphetamine, followed by MDMA and pseudoephedrine. The optimum slope cutoff for identifying patient specimens containing (meth)amphetamine was 320 (sensitivity, 96%; specificity, 90%; PPV, 92%). High concentrations of less reactive compounds may mask low concentrations of amphetamines. Use of the slope of the dose-response relationship in patient urine specimens can enhance the PPV of presumptive positive immunoassay results but does not exclude the presence of low amphetamine concentrations in samples containing high concentrations of cross-reactive species.

  5. Woodbridge research facility remedial investigation/feasibility study. Sampling and analysis plan vol 1: Field sampling plan vol II: Quality assurance project plan. Addendum 1

    Energy Technology Data Exchange (ETDEWEB)

    Wisbeck, D.; Thompson, P.; Williams, T.; Ehlers, M.; Eliass, M.

    1996-09-01

    U.S. Army Woodbridge Research Facility (WRF) was used in the past as a major military communications center and a research and development laboratory where electromagnetic pulse energy was tested on military and other equipment. WRF is presently an inactive facility pursuant to the 1991 Base Realignment and Closure list. Past investigation activities indicate that polychlorinated biphenyl compounds (PCBs) are the primary chemicals of concern. This task calls for provision of the necessary staff and equipment to provide remedial investigation/feasibility study support for the USAEC BRAC Program investigation at WRF. This Sampling and Analysis Plan, Addendum 1, Field Sampling Plan presents the sample location and rationale for additional samples required to complete the RI/FS; and the Quality Assurance Project Plan presents any additional data quality objectives and proposed laboratory methods for chemical analysis of samples.

  6. With how many users should you test a medical infusion pump? Sampling strategies for usability tests on high-risk systems

    NARCIS (Netherlands)

    Schmettow, Martin; Vos, Wendy; Schraagen, Johannes Martinus Cornelis

    2013-01-01

    Usability testing is recognized as an effective means to improve the usability of medical devices and prevent harm for patients and users. Effectiveness of problem discovery in usability testing strongly depends on size and representativeness of the sample. We introduce the late control strategy,

  7. Adapting Champion's Breast Cancer Fear Scale to colorectal cancer: psychometric testing in a sample of older Chinese adults.

    Science.gov (United States)

    Leung, Doris Y P; Wong, Eliza M L; Chan, Carmen W H

    2014-06-01

    Colorectal cancer (CRC) is the most common type of cancer in both men and women, and older adults are more susceptible to this disease. Previous studies suggest that cancer fear may be a key predictor of participation in cancer screening. Yet there is a lack of validated measuring tools of fear relating to CRC for the Chinese older adult population. This study aims to test the psychometric properties of the Chinese version of the Colorectal Cancer Fear Scale (CRCFS), adapting from the Champion's Breast Cancer Fear Scale. The CRCFS was developed by altering the wording 'breast cancer' to 'colorectal cancer'. Interviewer-administered surveys were carried out with a convenience sample of 250 community-dwelling adults aged at least 60 years old without a history of cancer. A subsample of 40 participants completed the scale again at one-month. Confirmatory factor analysis revealed that the one-factor model provided excellent fits to the overall data, and two randomly split samples. Cronbach's alpha of the scale was 0.95 and test-retest reliability was 0.52. Positive and significant correlations of CRC Cancer Fear with CRC-related susceptibility, severity and barriers were observed. A non-linear relationship with benefits was found. The findings provide support for the psychometric properties of a Chinese version of the Champion Cancer Fear with an adaption to CRC in a sample of community dwelling older Chinese adults. The scale provides a useful tool to assess CRC-related fear, which interventions should address in order to improve screening rates among older Chinese adults. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. 78 FR 9828 - Establishment of User Fees for Filovirus Testing of Nonhuman Primate Liver Samples

    Science.gov (United States)

    2013-02-12

    ..., the commenter indicated his/her support for the testing of animals that pose a threat to human life. A... actions to encourage a private market for filovirus testing. III. Alternatives Considered As stated... testing, we considered several alternatives to meet the testing requirement. One alternative was to wait...

  9. Racial disparities in BRCA testing and cancer risk management across a population-based sample of young breast cancer survivors.

    Science.gov (United States)

    Cragun, Deborah; Weidner, Anne; Lewis, Courtney; Bonner, Devon; Kim, Jongphil; Vadaparampil, Susan T; Pal, Tuya

    2017-07-01

    Breast cancer (BC) disparities may widen with genomic advances. The authors compared non-Hispanic white (NHW), black, and Hispanic BC survivors for 1) cancer risk-management practices among BRCA carriers and 2) provider discussion and receipt of genetic testing. A population-based sample of NHW, black, and Hispanic women who had been diagnosed with invasive BC at age 50 years or younger from 2009 to 2012 were recruited through the state cancer registry. Multiple logistic regression was used to compare cancer risk-management practices in BRCA carriers and associations of demographic and clinical variables with provider discussion and receipt of testing. Of 1622 participants, 159 of 440 (36.1%) black women, 579 of 897 (64.5%) NHW women, 58 of 117 (49.6%) Spanish-speaking Hispanic women, and 116 of 168 (69%) English-speaking Hispanic women underwent BRCA testing, of whom 90 had a pathogenic BRCA mutation identified. Among BRCA carriers, the rates of risk-reducing mastectomy and risk-reducing salpingo-oophorectomy were significantly lower among black women compared with Hispanic and NHW women after controlling for clinical and demographic variables (P = .025 and P = .008, respectively). Compared with NHW women, discussion of genetic testing with a provider was 16 times less likely among black women (P testing arise from cancer risk-management practice options. Furthermore, lower BRCA testing rates among blacks may partially be because of a lower likelihood of provider discussion. Future studies are needed to improve cancer risk identification and management practices across all populations to prevent the widening of disparities. Cancer 2017;123:2497-05. © 2017 American Cancer Society. © 2017 American Cancer Society.

  10. Venous Sampling

    Science.gov (United States)

    ... neck to help locate abnormally functioning glands or pituitary adenoma . This test is most often used after an unsuccessful neck exploration. Inferior petrosal sinus sampling , in which blood samples are taken from veins that drain the pituitary gland to study disorders related to pituitary hormone ...

  11. Testing the validity of the proposed ICD-11 PTSD and complex PTSD criteria using a sample from Northern Uganda

    Directory of Open Access Journals (Sweden)

    Siobhan Murphy

    2016-09-01

    Full Text Available Background: The International Classification of Diseases (ICD-11 is currently under development with proposed changes recommended for the posttraumatic stress disorder (PTSD diagnosis and the inclusion of a separate complex PTSD (CPTSD disorder. Empirical studies support the distinction between PTSD and CPTSD; however, less research has focused on non-western populations. Objective: The aim of this study was to investigate whether distinct PTSD and CPTSD symptom classes emerged and to identify potential risk factors and the severity of impairment associated with resultant classes. Methods: A latent class analysis (LCA and related analyses were conducted on 314 young adults from Northern Uganda. Fifty-one percent were female and participants were aged between 18 and 25 years. Forty percent of the participants were former child soldiers (n=124 while the remaining participants were civilians (n=190. Results: The LCA revealed three classes: a CPTSD class (40.2%, a PTSD class (43.8%, and a low symptom class (16%. Child soldier status was a significant predictor of both CPTSD and PTSD classes (OR=5.96 and 2.82, respectively. Classes differed significantly on measures of anxiety/depression, conduct problems, somatic complaints, and war experiences. Conclusions: To conclude, this study provides preliminary support for the proposed distinction between PTSD and CPTSD in a young adult sample from Northern Uganda. However, future studies are needed using larger samples to test alternative models before firm conclusions can be made.

  12. Testing the validity of the proposed ICD-11 PTSD and complex PTSD criteria using a sample from Northern Uganda.

    Science.gov (United States)

    Murphy, Siobhan; Elklit, Ask; Dokkedahl, Sarah; Shevlin, Mark

    2016-01-01

    The International Classification of Diseases (ICD-11) is currently under development with proposed changes recommended for the posttraumatic stress disorder (PTSD) diagnosis and the inclusion of a separate complex PTSD (CPTSD) disorder. Empirical studies support the distinction between PTSD and CPTSD; however, less research has focused on non-western populations. The aim of this study was to investigate whether distinct PTSD and CPTSD symptom classes emerged and to identify potential risk factors and the severity of impairment associated with resultant classes. A latent class analysis (LCA) and related analyses were conducted on 314 young adults from Northern Uganda. Fifty-one percent were female and participants were aged between 18 and 25 years. Forty percent of the participants were former child soldiers (n=124) while the remaining participants were civilians (n=190). The LCA revealed three classes: a CPTSD class (40.2%), a PTSD class (43.8%), and a low symptom class (16%). Child soldier status was a significant predictor of both CPTSD and PTSD classes (OR=5.96 and 2.82, respectively). Classes differed significantly on measures of anxiety/depression, conduct problems, somatic complaints, and war experiences. To conclude, this study provides preliminary support for the proposed distinction between PTSD and CPTSD in a young adult sample from Northern Uganda. However, future studies are needed using larger samples to test alternative models before firm conclusions can be made.

  13. Data from pumping and injection tests and chemical sampling in the geothermal aquifer at Klamath Falls, Oregon

    Science.gov (United States)

    Benson, S.M.; Janik, C.J.; Long, D.C.; Solbau, R.D.; Lienau, P.J.

    1984-01-01

    A seven-week pumping and injection tests in the geothermal aquifer at Klamath Falls, Oregon, in 1983 provided new information on hydraulic properties of the aquifer. The Open-File Data Report on the tests includes graphs of water levels measured in 50 wells, temperature measurement in 17 wells , daily air-temperatures in relation to discharge of thermal water from more than 70 pumped and artesian wells, tables of monthly mean air temperatures and estimates of discharges of thermal water during a normal year, and tables of chemical and isotopic analyses on samples from 12 wells. The water-level measurements reflect the effects of pumping, injection, and recovery over about 1.7 square miles of the hot-well area of Klamath Falls. The pumped well, City Well No 1, and the injection well at the Klamath County Museum are components of a proposed District Heating Plan. The study was funded principally under contracts from the U.S. Department of Energy to the Lawrence Berkeley Laboratory, Stanford University, and the Oregon Institute of Technology, with coordination and chemical sampling provided under the Geothermal Research Program, U.S. Geological Survey. Support was received from the City of Klamath Falls, Klamath County Chamber of Commerce, Citizens for Responsible Geothermal Development, and many citizen volunteers. (USGS)

  14. Planning considerations for a Mars Sample Receiving Facility: summary and interpretation of three design studies.

    Science.gov (United States)

    Beaty, David W; Allen, Carlton C; Bass, Deborah S; Buxbaum, Karen L; Campbell, James K; Lindstrom, David J; Miller, Sylvia L; Papanastassiou, Dimitri A

    2009-10-01

    It has been widely understood for many years that an essential component of a Mars Sample Return mission is a Sample Receiving Facility (SRF). The purpose of such a facility would be to take delivery of the flight hardware that lands on Earth, open the spacecraft and extract the sample container and samples, and conduct an agreed-upon test protocol, while ensuring strict containment and contamination control of the samples while in the SRF. Any samples that are found to be non-hazardous (or are rendered non-hazardous by sterilization) would then be transferred to long-term curation. Although the general concept of an SRF is relatively straightforward, there has been considerable discussion about implementation planning. The Mars Exploration Program carried out an analysis of the attributes of an SRF to establish its scope, including minimum size and functionality, budgetary requirements (capital cost, operating costs, cost profile), and development schedule. The approach was to arrange for three independent design studies, each led by an architectural design firm, and compare the results. While there were many design elements in common identified by each study team, there were significant differences in the way human operators were to interact with the systems. In aggregate, the design studies provided insight into the attributes of a future SRF and the complex factors to consider for future programmatic planning.

  15. Pre-exposure to food temptation reduces subsequent consumption: A test of the procedure with a South-African sample.

    Science.gov (United States)

    Duh, Helen Inseng; Grubliauskiene, Aiste; Dewitte, Siegfried

    2016-01-01

    It has been suggested that the consumption of unhealthy Westernized diet in a context of poverty and resultant food insecurity may have contributed to South-Africa's status of the third fattest country in the World. Considering that a number of South-Africans are reported to have experienced, or are still experiencing food insecurity, procedures which have been shown to reduce the consumption of unhealthy food in higher income countries may be ineffective in South-Africa. We thus tested the robustness of the so called pre-exposure procedure in South-Africa. We also tested the moderating role of childhood poverty in the pre-exposure procedure. With the pre-exposure procedure, a respondent is exposed to a tempting unhealthy food (e.g. candy) in a context that is designed such that eating the food interferes with a task goal. The typical result is that this procedure spills over and reduces consumption of similar tempting food later on. An experimental study conducted in a South-African laboratory showed that the pre-exposure effect is robust even with a sample, where food insecurity prevails. Childhood poverty did not moderate the effect. This study proves that behavioral procedures aimed at reducing the consumption of unhealthy food would be valuable in less rich non-Western countries. Further testing of the robustness of the pre-exposure effect is however recommended in other poorer food insecure countries. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Results of Hg speciation testing on DWPF SMECT-8, OGCT-1, AND OGCT-2 samples

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-02-22

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences, Inc. in Seattle, WA on behalf of the Savannah River Remediation (SRR) Mercury Task Team. The sixteenth shipment of samples was designated to include a Defense Waste Processing Facility (DWPF) Slurry Mix Evaporator Condensate Tank (SMECT) sample from Sludge Receipt and Adjustment Tank (SRAT) Batch 738 processing and two Off-Gas Condensate Tank (OGCT) samples, one following Batch 736 and one following Batch 738. The DWPF sample designations for the three samples analyzed are provided. The Batch 738 ‘End of SME Cycle’ SMECT sample was taken at the conclusion of Slurry Mix Evaporator (SME) operations for this batch and represents the fourth SMECT sample examined from Batch 738. Batch 738 experienced a sludge slurry carryover event, which introduced sludge solids to the SMECT that were particularly evident in the SMECT-5 sample, but less evident in the ‘End of SME Cycle’ SMECT-8 sample.

  17. Testing of toxicology and emissions-sampling methodology for ocean incineration of hazardous wastes. Final report, January 1985-January 1986

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, P.; Cooke, M.; Carr, S.; Piispanen, W.; Werme, C.

    1988-05-01

    This report addresses the development and testing of a system to expose marine organisms to hazardous-waste emissions in order to assess the potential toxicity of incinerator plumes at sea as they contact the marine environment through air-sea exchange and initial mixing. A sampling train was designed and tested at EPA's land-based hazardous-waste incinerator, using transformer oil as a waste feed. The incinerator was operated under conditions which would be appropriate for at-sea incinerators. The sampling train (Marine Incineration Biological Assessment Sampler--MIBAS) provides a sea-water sample containing a plume emission for the marine organisms testing. Five toxicity-test protocols were refined and/or developed for use in the program: (1) a sea-urchin fertilization test; (2) a chronic test using macroalgae Champia parvula; (3) a 7-day chronic test using growth and reproduction of the crustacean Mysidopsis bahia; (4) a 7-day growth and survival test with the fish Menidia beryllina; and (5) a 7-day life-cycle test using the archiannelid worm Dinophilus gyrocilatus. The results of applying these tests during a hazardous-waste burn are given.

  18. 76 FR 72950 - Draft Guidance for Industry: Use of Nucleic Acid Tests on Pooled and Individual Samples From...

    Science.gov (United States)

    2011-11-28

    ... HUMAN SERVICES Food and Drug Administration Draft Guidance for Industry: Use of Nucleic Acid Tests on... document entitled ``Guidance for Industry: Use of Nucleic Acid Tests (NAT) on Pooled and Individual Samples... Whole Blood and blood components for transfusion or for further manufacture, including recovered plasma...

  19. Optimization of Sample Preparation for the Identification and Quantification of Saxitoxin in Proficiency Test Mussel Sample using Liquid Chromatography-Tandem Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Kirsi Harju

    2015-11-01

    Full Text Available Saxitoxin (STX and some selected paralytic shellfish poisoning (PSP analogues in mussel samples were identified and quantified with liquid chromatography-tandem mass spectrometry (LC-MS/MS. Sample extraction and purification methods of mussel sample were optimized for LC-MS/MS analysis. The developed method was applied to the analysis of the homogenized mussel samples in the proficiency test (PT within the EQuATox project (Establishment of Quality Assurance for the Detection of Biological Toxins of Potential Bioterrorism Risk. Ten laboratories from eight countries participated in the STX PT. Identification of PSP toxins in naturally contaminated mussel samples was performed by comparison of product ion spectra and retention times with those of reference standards. The quantitative results were obtained with LC-MS/MS by spiking reference standards in toxic mussel extracts. The results were within the z-score of ±1 when compared to the results measured with the official AOAC (Association of Official Analytical Chemists method 2005.06, pre-column oxidation high-performance liquid chromatography with fluorescence detection (HPLC-FLD.

  20. Optimization of Sample Preparation for the Identification and Quantification of Saxitoxin in Proficiency Test Mussel Sample using Liquid Chromatography-Tandem Mass Spectrometry.

    Science.gov (United States)

    Harju, Kirsi; Rapinoja, Marja-Leena; Avondet, Marc-André; Arnold, Werner; Schär, Martin; Burrell, Stephen; Luginbühl, Werner; Vanninen, Paula

    2015-11-25

    Saxitoxin (STX) and some selected paralytic shellfish poisoning (PSP) analogues in mussel samples were identified and quantified with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Sample extraction and purification methods of mussel sample were optimized for LC-MS/MS analysis. The developed method was applied to the analysis of the homogenized mussel samples in the proficiency test (PT) within the EQuATox project (Establishment of Quality Assurance for the Detection of Biological Toxins of Potential Bioterrorism Risk). Ten laboratories from eight countries participated in the STX PT. Identification of PSP toxins in naturally contaminated mussel samples was performed by comparison of product ion spectra and retention times with those of reference standards. The quantitative results were obtained with LC-MS/MS by spiking reference standards in toxic mussel extracts. The results were within the z-score of ±1 when compared to the results measured with the official AOAC (Association of Official Analytical Chemists) method 2005.06, pre-column oxidation high-performance liquid chromatography with fluorescence detection (HPLC-FLD).

  1. Sperm tail flexibility test: a simple test for selecting viable spermatozoa for intracytoplasmic sperm injection from semen samples without motile spermatozoa

    Directory of Open Access Journals (Sweden)

    Soares Jonathas Borges

    2003-01-01

    Full Text Available PURPOSE: The objective was to describe the results of the injection of immotile spermatozoa with flexible tails when only immotile spermatozoa are present in the semen sample. METHODS: A retrospective study was conducted to analyze the procedure results for 10 couples who participated in our intracytoplasmic sperm injection program. The sperm tail was considered flexible when it moved up and down independently of the head movement, and it was considered inflexible when the movement occurred together (tail plus head. The fertilization and pregnancy rate were analyzed. RESULTS: The normal fertilization rate (presence of 2 pronuclei was 30.3% (40/132, and the abnormal fertilization rate (presence of less than or more than 2 pronuclei was 6.81% (9/132. A total of 52 embryos were obtained with 9 transfer procedures performed (pregnancy rate: 11.12%. CONCLUSIONS: The sperm tail flexibility test (STFT is an easy and cost-effective way for selecting viable immotile spermatozoa and can be used as an alternative method for determining the viability of spermatozoa. This test seems to be a simple and risk-free method when compared to the swelling test.

  2. Empirical testing of modified Salmonella MLST in aquatic environmental samples by in silico analysis.

    Science.gov (United States)

    Ho, Ying-Ning; Chou, Ming-Yuan; Tsai, Hsin-Chi; Huang, Tung-Yi; Fan, Cheng-Wei; Hsu, Bing-Mu

    2017-03-01

    Multilocus sequence typing (MLST) is an approach for prediction of Salmonella servoar and eBRUST groups (eBGs) based on seven typing scheme of housekeeping genes. Up to date, >220.000 allelic profiles and 65,973 Salmonella strains have been established in the MLST database. Several studies have modified MLST method with fewer targeted housekeeping genes for the purpose of economy and efficiency. Nevertheless, no study has conducted systematically to evaluate the correlation between the numbers of housekeeping genes targeted and the accuracy of prediction rate. In this study, we aimed to tackle this problem by extracting data from the MLST database as a whole using the software RStudio. Our results indicated that as the numbers of genes in MLST scheme increased, the accuracy of the eBGs prediction rate increased and reached 100% when the gene numbers are greater than or equal to 5. To examine the applicability of the approach, 395 environmental water samples were subjected to this study. A set of 52 Salmonella enterica isolates was initially used to develop MLST targeting seven housekeeping genes. A total of 29 sequence types, including 11 new sequence types were found among the 52 sequenced isolates that differentiated into 19 serotypes. Moreover, two novel sequence types did not belong to current classification. Our results show that the outcome in the three-gene sequence typing (aroC, hisD, and purE) was as accurate as in the seven-gene sequence typing for prediction of environmental Salmonella isolates. Our data suggested that this five-gene and reduced gene-number sequence-typing scheme can serve as an alternative modified MLST when effectiveness and financial management were the concerns. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Microbial Safety of Low Water Activity Foods: Study of Simulated and Durban Household Samples

    OpenAIRE

    Ijabadeniyi, O. A.; Pillay, Y.

    2017-01-01

    Sixty household low water activity foods were examined and a simulative study was conducted in a high sugar, low aw almond and macadamia butter to determine the survival of Bacillus cereus and Staphylococcus aureus ATCC 25923. Results obtained from 60 low aw samples collected at household level had some significant differences (P≤0,05) within food categories amongst the various tests. Spices had the highest number of aerobic bacteria, aerobic spore-formers, anaerobic spore-formers, and S. aur...

  4. Desert Research and Technology Studies Exposure of Lotus Coated Electrodynamic Shield Samples

    Science.gov (United States)

    Rodriquez, Marcello; Peters, Wanda C.; Straka, Sharon A.; Jones, Craig B.

    2011-01-01

    The Lotus dust mitigation coating and the electrodynamic shield (EDS) are two new technologies currently being developed by NASA as countermeasures for addressing dust accumulation for long-duration human space exploration. These combined technologies were chosen by the Habitation Demonstration Unit (HDU) program for desert dust exposure at the Desert Research and Technologies Studies (D-RaTS) test site in Arizona. Characterization of these samples was performed prior to, during and post D-RaTS exposure.

  5. Study of probe-sample distance for biomedical spectra measurement

    Directory of Open Access Journals (Sweden)

    Li Lei

    2011-11-01

    Full Text Available Abstract Background Fiber-based optical spectroscopy has been widely used for biomedical applications. However, the effect of probe-sample distance on the collection efficiency has not been well investigated. Method In this paper, we presented a theoretical model to maximize the illumination and collection efficiency in designing fiber optic probes for biomedical spectra measurement. This model was in general applicable to probes with single or multiple fibers at an arbitrary incident angle. In order to demonstrate the theory, a fluorescence spectrometer was used to measure the fluorescence of human finger skin at various probe-sample distances. The fluorescence spectrum and the total fluorescence intensity were recorded. Results The theoretical results show that for single fiber probes, contact measurement always provides the best results. While for multi-fiber probes, there is an optimal probe distance. When a 400- μm excitation fiber is used to deliver the light to the skin and another six 400- μm fibers surrounding the excitation fiber are used to collect the fluorescence signal, the experimental results show that human finger skin has very strong fluorescence between 475 nm and 700 nm under 450 nm excitation. The fluorescence intensity is heavily dependent on the probe-sample distance and there is an optimal probe distance. Conclusions We investigated a number of probe-sample configurations and found that contact measurement could be the primary choice for single-fiber probes, but was very inefficient for multi-fiber probes. There was an optimal probe-sample distance for multi-fiber probes. By carefully choosing the probe-sample distance, the collection efficiency could be enhanced by 5-10 times. Our experiments demonstrated that the experimental results of the probe-sample distance dependence of collection efficiency in multi-fiber probes were in general agreement with our theory.

  6. Note: Planetary gravities made simple: Sample test of a Mars rover wheel

    Science.gov (United States)

    Viera-López, G.; Serrano-Muñoz, A.; Amigó-Vega, J.; Cruzata, O.; Altshuler, E.

    2017-08-01

    We introduce an instrument for a wide spectrum of experiments on gravities other than our planet's. It is based on a large Atwood machine where one of the loads is a bucket equipped with a single board computer and different sensors. The computer is able to detect the falling (or rising) and then the stabilization of the effective gravity and to trigger actuators depending on the experiment. Gravities within the range 0.4 g-1.2 g are easily achieved with acceleration noise of the order of 0.01 g. Under Martian gravity, we are able to perform experiments of approximately 1.5 s duration. The system includes features such as WiFi and a web interface with tools for the setup, monitoring, and data analysis of the experiment. We briefly show a case study in testing the performance of a model Mars rover wheel in low gravities.

  7. 42 CFR 493.801 - Condition: Enrollment and testing of samples.

    Science.gov (United States)

    2010-10-01

    ... provided by the PT program, signed by the analyst and the laboratory director, documenting that proficiency... date of the proficiency testing event. (6) PT is required for only the test system, assay, or...

  8. Estimating material elasticity by spherical indentation load-relaxation tests on viscoelastic samples of finite thickness.

    Science.gov (United States)

    Qiang, Bo; Greenleaf, James; Oyen, Michelle; Zhang, Xiaoming

    2011-07-01

    A two-step viscoelastic spherical indentation method is proposed to compensate for 1) material relaxation and 2) sample thickness. In the first step, the indenter is moved at a constant speed and the reaction force is measured. In the second step, the indenter is held at a constant position and the relaxation response of the material is measured. Then the relaxation response is fit with a multi-exponential function which corresponds to a three-branch general Maxwell model. The relaxation modulus is derived by correcting the finite ramp time introduced in the first step. The proposed model takes into account the sample thickness, which is important for applications in which the sample thickness is less than ten times the indenter radius. The model is validated numerically by finite element simulations. Experiments are carried out on a 10% gelatin phantom and a chicken breast sample with the proposed method. The results for both the gelatin phantom and the chicken breast sample agree with the results obtained from a surface wave method. Both the finite element simulations and experimental results show improved elasticity estimations by incorporating the sample thickness into the model. The measured shear elasticities of the 10% gelatin sample are 6.79 and 6.93 kPa by the proposed finite indentation method at sample thickness of 40 and 20 mm, respectively. The elasticity of the same sample is estimated to be 6.53 kPa by the surface wave method. For the chicken breast sample, the shear elasticity is measured to be 4.51 and 5.17 kPa by the proposed indentation method at sample thickness of 40 and 20 mm, respectively. Its elasticity is measured by the surface wave method to be 4.14 kPa.

  9. An innovative approach to sampling complex industrial emissions for use in animal toxicity tests: application to iron casting operations.

    Science.gov (United States)

    Palmer, W G; Scholz, R C; Moorman, W J

    1983-03-01

    Sampling of complex mixtures of airborne contaminants for chronic animal toxicity tests often involves numerous sampling devices, requires extensive sampling time, and yields forms of collected materials unsuitable for administration to animals. A method is described which used a high volume, wet venturi scrubber for collection of respirable fractions of emissions from iron foundry casting operations. The construction and operation of the sampler are presented along with collection efficiency data and its application to the preparation of large quantities of samples to be administered to animals by intratracheal instillation.

  10. Effect of the distribution of analyte concentration in lot, sample size, and number of analytical runs on food-testing results.

    Science.gov (United States)

    Watanabe, Takahiro; Matsuda, Rieko

    2012-10-24

    In testing, it is necessary to obtain the correct measured values that reflect analyte concentrations in the lot. Control of the analytical performance and appropriate sampling are essential to obtain the correct values. In the present study, we estimated the distribution of the analyte concentrations in specific food product lots and examined the influence of the sample size and the number of analytical runs on the variability of the testing results. The combinations of analyte and food studied were pesticide residues in fresh vegetables, nitrate in fresh vegetables, and food additives in processed meat products. The results of our study suggested the following: an increase in the sample size beyond a certain number does not efficiently reduce the variability of the test results; the specific sample size required to maintain the variability of the testing results at an appropriate level depends on the breadth of distribution of concentrations in the lot and the precision of the analysis; and increasing the number of analytical runs was more efficient in reducing the variability of the testing results than increasing the sample size, when the breadth of distribution of concentrations in the lot was narrow enough to be comparable with the analytical precision.

  11. 40 CFR 80.582 - What are the sampling and testing methods for the fuel marker?

    Science.gov (United States)

    2010-07-01

    ... requirements of this section may involve the use of hazardous materials, operations and equipment. This section...) What process must a test facility follow in order to qualify a test method for determining the fuel... control charts from the mandatory quality control testing prescribed in paragraph 7.1 of the reference...

  12. A Note on Two-Sample Tests for Comparing Intra-Individual Genetic Sequence Diversity between Populations

    Science.gov (United States)

    Giorgi, E. E.; Bhattacharya, T.

    2013-01-01

    Summary present four U-statistic based tests to compare genetic diversity between different samples. The proposed tests improved upon previously used methods by accounting for the correlations in the data. We find, however, that the same correlations introduce an unacceptable bias in the sample estimators used for the variance and covariance of the inter-sequence genetic distances for modest sample sizes. Here, we compute unbiased estimators for these and test the resulting improvement using simulated data. We also show that, contrary to the claims in Gilbert et al., it is not always possible to apply the Welch–Satterthwaite approximate t-test, and we provide explicit formulas for the degrees of freedom to be used when, on the other hand, such approximation is indeed possible. PMID:23004569

  13. Determination of N-acetylglucosamine in cosmetic formulations and skin test samples by hydrophilic interaction liquid chromatography and UV detection.

    Science.gov (United States)

    Pedrali, Alice; Bleve, Mariella; Capra, Priscilla; Jonsson, Tobias; Massolini, Gabriella; Perugini, Paola; Marrubini, Giorgio

    2015-03-25

    N-Acetylglucosamine is an ingredient in pharmaceuticals, nutritional supplements and in cosmetics. N-Acetylglucosamine in cosmetics is expected to improve skin hydration, reparation, and to contribute as anti-wrinkle agent. This study reports on the validation and application of an HPLC method based on HILIC and UV detection for determining N-acetylglucosamine in cosmetics and in samples obtained after testing the skin exposed to cosmetics formulations. The chromatographic column used is a ZIC(®)-pHILIC (150 mm × 4.6 mm, 5 μm particle size) on which a mobile phase containing acetonitrile-aqueous KH2PO4 (70:30, v/v) 15 mM was applied in isocratic elution mode injecting 20 μl of sample at 0.5 ml/min constant flow-rate and 10±1°C column temperature. Under these conditions the total run time was 10 min and N-acetylglucosamine eluted baseline separated from all other compounds in the samples. Calibration in the range from 40 to 80 μg/ml allowed to assess the method linearity (R(2)>0.999) in a concentration range corresponding to about 50% to 120% of the expected levels of N-acetylglucosamine in the formulations. Precision expressed by RSD% was always better than 2% in intra-day and inter-day assays of authentic samples. Accuracy was in all cases within 95-105% of the expected concentration value in formulations containing N-acetylglucosamine. The sensitivity of the method was at the level of 10 μg/ml as limit of detection, and at 40 μg/ml as limit of quantitation. The application of the method to formulations containing solid lipid nanoparticles documents its usefulness in cosmetic quality control. The results witness that the method is also suitable for the determination of N-acetylglucosamine in samples obtained from skin test strips. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Test-retest studies in quantitative sensory testing

    DEFF Research Database (Denmark)

    Werner, M U; Petersen, M A; Bischoff, J M

    2013-01-01

    Quantitative sensory testing (QST) investigates the graded psychophysical response to controlled thermal, mechanical, electrical or chemical stimuli, allowing quantification of clinically relevant perception and pain thresholds. The methods are ubiquitously used in experimental and clinical pain...... research, and therefore, the need for uniform assessment procedures has been emphasised. However, varying consistency and transparency in the statistical methodology seem to occur in the QST literature. Sixteen publications, evaluating aspects of QST variability, from 2010 to 2012, were critically reviewed...

  15. Development of internal forest soil reference samples and testing of digestion methods

    Science.gov (United States)

    J.E. Hislop; J.W. Hornbeck; S.W. Bailey; R.A. Hallett

    1998-01-01

    Our research requires determinations of total elemental concentrations of forest soils. The lack of certified forest soil reference materials led us to develop internal reference samples. Samples were collected from three soil horizons (Oa, B, and C) at three locations having forested, acidic soils similar to those we commonly analyze. A shatterbox was used to...

  16. 76 FR 69585 - Testing and Labeling Pertaining to Product Certification Regarding Representative Samples for...

    Science.gov (United States)

    2011-11-08

    ... material change in the product's design or manufacturing process, including the sourcing of component parts... example, if a bicycle handlebar sample is manufactured from the same grade of steel and with the same... met by a range of probability-based sampling designs, including, but not limited to, simple random...

  17. Test of Tree Core Sampling for Screening of Toxic Elements in Soils from a Norwegian Site

    DEFF Research Database (Denmark)

    Nielsen, Mette Algreen; Rein, Arno; Legind, Charlotte Nielsen

    2011-01-01

    Tree core samples have been used to delineate organic subsurface plumes. In 2009 and 2010, samples were taken at trees growing on a former dump site in Norway and analyzed for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and zinc (Zn). Concentrations in wood were in averag...

  18. Testing Different Versions of the Affective Neuroscience Personality Scales in a Clinical Sample

    Science.gov (United States)

    Geir, Pedersen; Selsbakk, Johansen Merete; Theresa, Wilberg; Sigmund, Karterud

    2014-01-01

    Background As a tool to investigate the experiences of six primary emotions, Davis, Panksepp, and Normansell [1] developed the Affective Neuroscience Personality Scales (ANPS). However, the psychometric properties of the ANPS have been questioned, and in particular the factor structure. This study replicates earlier psychometric studies on ANPS in a sample of (546) personality disordered patients, and also includes ANPS-S, a recent short version of ANPS by Pingault and colleagues [2], and a truncated version of BANPS by Barrett and colleagues [3]. Methodology/Principal Findings The study of the full ANPS revealed acceptable internal consistencies of the primary emotion subscales, ranging from 0.74–0.87. However, factor analyses revealed poor to mediocre fit for a six factor solution. Correlational analyses, in addition, revealed too high correlations between PLAY and SEEK, and between SADNESS and FEAR. The two short versions displayed better psychometric properties. The range of internal consistency was 0.61–0.80 for the BANPS scales and 0.65–84 for the ANPS-S. Backward Cronbach Alpha Curves indicated potentials for improvement on all three versions of the questionnaire. Items retained in the short versions did not systematically cover the full theoretical content of the long scales, in particular for CARE and SADNESS in the BANPS. The major problems seem to reside in the operationalization of the CARE and SADNESS subscales of ANPS. Conclusions/Significance Further work needs to be done in order to realize a psychometrically sound instrument for the assessment of primary emotional experiences. PMID:25289939

  19. Preliminary study of Histamine in Rainbow trout (Oncorhynchus mykiss samples from fish markets in Tehran

    Directory of Open Access Journals (Sweden)

    Z Mashak

    2011-08-01

    Full Text Available Histidine is one of non-protein nitrogen extractives which found in fish such as Salmonidae family (trout is belonged this family.Members of this family has high amounts of Histidine compared to other foods. Some Salmon microbial flora can decarboxylated Histidine to Histamine and this metabolite is a hazard component for human. Evaluation of Histamine levels in Salmon via a fast and accurate method can be useful for decreasing the intensity of these hazards. In this study evaluated psychrophilic and mesophilic aerobic bacteria and also histamine level in purchased salmon samples from fish markets in Tehran by ELISA method (Rida Screen Histamine Kits. A total of 60 samples of Rainbow trout (Oncorhynchus mykiss purchased from fish markets and assayed for Histamine by using Rida Screen Histamine ELISA Kits. Bacterial enumeration was performed on 10-fold diluted samples at 25°C and 35°C for mesophilic and psychrophilic bacteria, respectively. The range of Histamine content was 4 to 28mg/100g (14.18mg/100g. 12.50 percent of samples had Histamine content above the international standard level (20mg/100g. Data achieved by bacterial enumeration and ELISA test were analyzed by Pearson correlation test indicated that direct relationship between histamine and the number of bacteria in fish samples is established (p

  20. The 4-vessel Sampling Approach to Integrative Studies of Human Placental Physiology In Vivo.

    Science.gov (United States)

    Holme, Ane M; Holm, Maia B; Roland, Marie C P; Horne, Hildegunn; Michelsen, Trond M; Haugen, Guttorm; Henriksen, Tore

    2017-08-02

    The human placenta is highly inaccessible for research while still in utero. The current understanding of human placental physiology in vivo is therefore largely based on animal studies, despite the high diversity among species in placental anatomy, hemodynamics and duration of the pregnancy. The vast majority of human placenta studies are ex vivo perfusion studies or in vitro trophoblast studies. Although in vitro studies and animal models are essential, extrapolation of the results from such studies to the human placenta in vivo is uncertain. We aimed to study human placenta physiology in vivo at term, and present a detailed protocol of the method. Exploiting the intraabdominal access to the uterine vein just before the uterine incision during planned cesarean section, we collect blood samples from the incoming and outgoing vessels on the maternal and fetal sides of the placenta. When combining concentration measurements from blood samples with volume blood flow measurements, we are able to quantify placental and fetal uptake and release of any compound. Furthermore, placental tissue samples from the same mother-fetus pairs can provide measurements of transporter density and activity and other aspects of placental functions in vivo. Through this integrative use of the 4-vessel sampling method we are able to test some of the current concepts of placental nutrient transfer and metabolism in vivo, both in normal and pathological pregnancies. Furthermore, this method enables the identification of substances secreted by the placenta to the maternal circulation, which could be an important contribution to the search for biomarkers of placenta dysfunction.

  1. Results of Hg speciation testing on tanks 30, 32, and 37 depth samples

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-11-30

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences, Inc. in Seattle, WA on behalf of the Savannah River Remediation (SRR) Mercury Task Team. The twelfth shipment of samples was designated to include 3H evaporator system Tank 30, 32, and 37 depth samples. The Tank 30 depth sample (HTF-30-15-70) was taken at 190 inches from the tank bottom and the Tank 32 depth sample (HTF-32-15-68) was taken at 89 inches from the tank bottom and both were shipped to SRNL on June 29, 2015 in an 80 mL stainless steel dip bottles. The Tank 37 surface sample (HTF-37-15-94) was taken around 253.4 inches from the tank bottom and shipped to SRNL on July 21, 2015 in an 80 mL stainless steel dip bottle. All samples were placed in the SRNL Shielded Cells and left unopened until intermediate dilutions were made on July 24, 2015 using 1.00 mL of sample diluted to 100.00 mL with deionized H2O. A 30 mL Teflon® bottle was rinsed twice with the diluted tank sample and then filled leaving as little headspace as possible. It was immediately removed from the Shielded Cells and transferred to refrigerated storage where it remained at 4 °C until final dilutions were made on October 20. A second portion of the cells diluted tank sample was poured into a shielded polyethylene bottle and transferred to Analytical Development for radiochemical analysis data needed for Hazardous Material Transportation calculations.

  2. Study of gastric cancer samples using terahertz techniques

    Science.gov (United States)

    Wahaia, Faustino; Kasalynas, Irmantas; Seliuta, Dalius; Molis, Gediminas; Urbanowicz, Andrzej; Carvalho Silva, Catia D.; Carneiro, Fatima; Valusis, Gintaras; Granja, Pedro L.

    2014-08-01

    In the present work, samples of healthy and adenocarcinoma-affected human gastric tissue were analyzed using transmission time-domain THz spectroscopy (THz-TDS) and spectroscopic THz imaging at 201 and 590 GHz. The work shows that it is possible to distinguish between normal and cancerous regions in dried and paraffin-embedded samples. Plots of absorption coefficient α and refractive index n of normal and cancer affected tissues, as well as 2-D transmission THz images are presented and the conditions for discrimination between normal and affected tissues are discussed.

  3. Comparison of bacterial culture and qPCR testing of rectal and pen floor samples as diagnostic approaches to detect enterotoxic Escherichia coli in nursery pigs

    DEFF Research Database (Denmark)

    Weber, N. R.; Nielsen, J. P.; Hjulsager, Charlotte Kristiane

    2017-01-01

    : bacterial culturing of faecal samples from three pigs (per pen) with clinical diarrhoea and subsequent testing for virulence genes in E. coli isolates; bacterial culturing of pen floor samples and subsequent testing for virulence genes in E. coli isolates; qPCR testing of pen floor samples in order....... The only adhesin factor detected in this study was F18. When comparing bacterial culture or qPCR testing of pen floor samples with detection of ETEC-positive diarrhoeic pigs by culture, agreement was found in 26 (83.9%, Kappa = 0.665) and 23 (74.2%, Kappa = 0.488) of the pens, respectively. Agreement...... was observed between the detection of ETEC by bacterial culture and qPCR in the same pen floor sample in 26 (83.9%, Kappa = 0.679) pens. Conclusion: We observed an acceptable agreement for the detection of ETEC-positive diarrhoeic nursery pigs in pen samples for both bacterial culture of pen floor samples...

  4. Can we rely on out-of-hospital blood samples? A prospective interventional study on the pre-analytical stability of blood samples under prehospital emergency medicine conditions.

    Science.gov (United States)

    Prottengeier, Johannes; Jess, Nicola; Harig, Frank; Gall, Christine; Schmidt, Joachim; Birkholz, Torsten

    2017-03-04

    Prehospital intravenous access provides the opportunity to sample blood from an emergency patient at the earliest possible moment in the course of acute illness and in a state prior to therapeutic interventions. Our study investigates the pre-analytical stability of biomarkers in prehospital emergency medicine and will answer the question whether an approach of blood sampling out in the field will deliver valid laboratory results. We prepared pairs of blood samples from healthy volunteers and volunteering patients post cardio-thoracic surgery. While one sample set was analysed immediately, the other one was subjected to a worse-than-reality treatment of 60 min time-lapse and standardized mechanical forces outside of the hospital through actual ambulance transport. We investigated 21 parameters comprising blood cells, coagulation tests, electrolytes, markers of haemolysis and markers of cardiac ischemia. Bland-Altman analysis was used to investigate differences between test groups. Differences between test groups were set against the official margins of test accuracy as given by the German Requirements for Quality Assurance of Medical Laboratory Examinations. Agreement between immediate analysis and our prehospital treatment is high as demonstrated by Bland-Altman plotting. Mechanical stress and time delay do not produce a systematic bias but only random inaccuracy. The limits of agreement for the tested parameters are generally within clinically acceptable ranges of variation and within the official margins as set by the German Requirements for Quality Assurance of Medical Laboratory Examinations. We subjected blood samples to a standardized treatment marking a worse-than-reality scenario of prehospital time delay and transport. Biomarkers including indicators of myocardial ischemia showed high pre-analytical stability. We conclude the validity of blood samples from a prehospital environment.

  5. Collection and Characterization of Samples for Establishment of a Serum Repository for Lyme Disease Diagnostic Test Development and Evaluation

    Science.gov (United States)

    Molins, Claudia R.; Sexton, Christopher; Young, John W.; Ashton, Laura V.; Pappert, Ryan; Beard, Charles B.

    2014-01-01

    Serological assays and a two-tiered test algorithm are recommended for laboratory confirmation of Lyme disease. In the United States, the sensitivity of two-tiered testing using commercially available serology-based assays is dependent on the stage of infection and ranges from 30% in the early localized disease stage to near 100% in late-stage disease. Other variables, including subjectivity in reading Western blots, compliance with two-tiered recommendations, use of different first- and second-tier test combinations, and use of different test samples, all contribute to variation in two-tiered test performance. The availability and use of sample sets from well-characterized Lyme disease patients and controls are needed to better assess the performance of existing tests and for development of improved assays. To address this need, the Centers for Disease Control and Prevention and the National Institutes of Health prospectively collected sera from patients at all stages of Lyme disease, as well as healthy donors and patients with look-alike diseases. Patients and healthy controls were recruited using strict inclusion and exclusion criteria. Samples from all included patients were retrospectively characterized by two-tiered testing. The results from two-tiered testing corroborated the need for novel and improved diagnostics, particularly for laboratory diagnosis of earlier stages of infection. Furthermore, the two-tiered results provide a baseline with samples from well-characterized patients that can be used in comparing the sensitivity and specificity of novel diagnostics. Panels of sera and accompanying clinical and laboratory testing results are now available to Lyme disease serological test users and researchers developing novel tests. PMID:25122862

  6. Relative age effects in fitness testing in a general school sample: how relative are they?

    Science.gov (United States)

    Veldhuizen, Scott; Cairney, John; Hay, John; Faught, Brent

    2015-01-01

    When children or adolescents are grouped by age or year of birth, older individuals tend to outperform younger ones. These phenomena are known as relative age effects (RAEs). RAEs may result directly from differences in maturation, but may also be associated with psychological, pedagogic or other factors. In this article, we attempt to quantify RAEs in a simple fitness task and to identify the mechanisms operating. Data come from a 5-year study of 2278 individuals that included repeated administrations of the 20 m shuttle run. We use mixed-effect modelling to characterise change over time and then examine residuals from these models for evidence of an effect for age relative to peers or for season of birth. Age alone appears to account for RAEs in our sample, with no effects for age relative to peers or month of birth. Age grouping produces large disparities for girls under 12, moderate ones for boys of all ages and negligible ones for girls between 12 and 15. RAEs for this task and population appear to arise from simple age differences. Similar methods may be useful in determining whether other explanations of RAEs are necessary in other contexts. Evaluation processes that take age into account have the potential to mitigate RAEs in general settings.

  7. Evaluation of a novel dried blood spot collection device (HemaSpot™) to test blood samples collected from dogs for antibodies to Leishmania infantum.

    Science.gov (United States)

    Rosypal, Alexa C; Pick, Leanne D; Hernandez, Jaime O Esquivel; Lindsay, David S

    2014-09-15

    Collection of blood samples from veterinary and wildlife patients is often challenging because the samples have to be collected on farm or in the wild under various environmental conditions. This poses many technical problems associated with venipuncture materials, their safe use and disposal, transportation and processing of collected samples. Dried blood spot (DBS) sample collection techniques offer a simple and practical alternative to traditional blood collection methods to obtain blood samples from animals for parasite antibody evaluation. The DBS collection devices are compact, simple to use, and are particularly useful for large number of samples. Additionally, DBS samples take up less space and they are easier to transport than traditional venipuncture-collected blood samples. Visceral leishmaniasis (VL) is a potentially fatal parasitic disease of dogs and humans and it is frequently diagnosed by antibody tests. Immunochromatographic tests (ICT) for antibodies to Leishmania infantum are commercially available for dogs and they produce qualitative results in minutes. Measurement of canine antibodies to L. infantum with the ICT using traditional venipuncture has been validated previously, but the use of DBS samples has not been evaluated using this method. The purpose of the present study was to determine the ability of DBS samples to detect antibodies to L. infantum in dogs using a commercial ICT assay. One hundred plasma samples from dogs experimentally infected with the LIVT-1 strain of L. infantum were collected by venipuncture and frozen. Individual samples were thawed, and then 80 μl plasma (2 drops) was aliquotted onto the 8-spoked disk pad on individual DBS sample collection devices (HemaSpot™, Spot-On Sciences, Austin, TX), dried, and stored in the dark at room temperature. After one month and six months, respectively, 2 spokes of the 8 spokes of the disk pad of each DBS sample were removed and eluted in 200 μl PBS. The eluate was used to test

  8. Efficacy of test of memory malingering Trial 1, Trial 2, the Retention Trial, and the Albany Consistency Index in a criterion group forensic neuropsychological sample.

    Science.gov (United States)

    Schroeder, R W; Buddin, W H; Hargrave, D D; VonDran, E J; Campbell, E B; Brockman, C J; Heinrichs, R J; Baade, L E

    2013-02-01

    The Test of Memory Malingering is one of the most popular and heavily researched validity tests available for use in neuropsychological evaluations. Recent research has suggested, however, that the original indices and cutoffs may require modifications to increase sensitivity rates. Some of these modifications lack cross-validation and no study has examined all indices in a single sample. This study compares Trial 1, Trial 2, the Retention Trial, and the newly created Albany Consistency Index in a criterion group forensic neuropsychological sample. Findings lend support for the newly created indices and cutoff scores. Implications and cautionary statements are provided and discussed.

  9. Service quality in banking: developing and testing measurement instrument with Latvian sample data

    Directory of Open Access Journals (Sweden)

    Jelena Titko

    2013-01-01

    Full Text Available The paper highlights the importance of managing service quality in banking that can positively affect customer satisfaction. The goal of the given study is to develop an instrument for measuring service quality perceived by Latvian banks’ retail customers and to determine the most important contributors to customer satisfaction. To achieve this purpose, randomly selected customers of Latvian banks were surveyed, using the authors’ developed questionnaire. The proposed instrument was tested for reliability and validity, using techniques of confirmatory factor analysis. Exploratory factor analysis yielded five service quality dimensions (factors that allowed constructing customer satisfaction factor model EPICA: E – expenses, P – product, I – image, C – competence and emotional intellect, A – access. The subsequent correlation analysis revealed that the strongest relationship is between customer satisfaction and C factor. The results of the current research are crucially important for Latvian banks’ executives because the majority of previous studies in the related field offered measurement scales adequate for measuring service quality in other industries. Besides, the proposed questionnaire is exclusively developed for Latvia and considers Latvian banking sector specifics.

  10. GY SAMPLING THEORY IN ENVIRONMENTAL STUDIES 2: SUBSAMPLING ERROR MEASUREMENTS

    Science.gov (United States)

    Sampling can be a significant source of error in the measurement process. The characterization and cleanup of hazardous waste sites require data that meet site-specific levels of acceptable quality if scientifically supportable decisions are to be made. In support of this effort,...

  11. Comparative Studies of Gasoline Samples Used in Nigeria | Faruq ...

    African Journals Online (AJOL)

    Comparative analysis was carried out on five samples of gasoline in the Nigerian market based on octane number, sulphur content, Reid vapour pressure, specific gravity, boiling point characteristics and chemical content. The result revealed that, Nigerian and Kuwait gasolines have low octane numbers in comparison to ...

  12. Sampling considerations for demographic and habitat studies of Northern Goshawks

    Science.gov (United States)

    Richard T. Reynolds; J. David Wiens; Suzanne M. Joy; Susan R. Salafsky

    2005-01-01

    We used mark-recapture methods to monitor Northern Goshawks (Accipiter gentilis) and their nests over 12 yr in an increasing sample of breeding territories (37 in 1991 to 121 in 2002) in northern Arizona. As many as 8 yr of repeated nest searching were required to identify the population of breeders, as individuals skipped egg-laying on territories...

  13. Strip transect sampling and analysis for avian habitat studies

    Science.gov (United States)

    Richard N. Conner; James G. Dickson

    1980-01-01

    Censusing procedures that detect effects of habitat treatment on birds are outlined. We suggest that only relative values of bird species diversity, equitability, abundance, and species richness need be obtained. We also suggest that 4, 250-m strip transects per treatment and 8-10 trips over each transect are adequate. Aspects of sampling design that affect within-...

  14. Reliability of the k{sub 0}-standardization method using geological sample analysed in a proficiency test

    Energy Technology Data Exchange (ETDEWEB)

    Pelaes, Ana Clara O.; Menezes, Maria Ângela de B.C., E-mail: anacpelaes@gmail.com, E-mail: menezes@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-11-01

    The Neutron Activation Analysis (NAA) is an analytical technique to determine the elemental chemical composition in samples of several matrices, that has been applied by the Laboratory for Neutron Activation Analysis, located at Centro de Desenvolvimento da Tecnologia Nuclear /Comissão Nacional de Energia Nuclear (Nuclear Technology Development Center/Brazilian Commission for Nuclear Energy), CDTN/CNEN, since the starting up of the TRIGA MARK I IPR-R1 reactor, in 1960. Among the methods of application of the technique, the k{sub 0}-standardization method, which was established at CDTN in 1995, is the most efficient and in 2003 it was reestablished and optimized. In order to verify the reproducibility of the results generated by the application of the k{sub 0}-standardization method at CDTN, aliquots of a geological sample sent by WEPAL (Wageningen Evaluating Programs for Analytical Laboratories) were analysed and its results were compared with the results obtained through the Intercomparison of Results organized by the International Atomic Energy Agency in 2015. WEPAL is an accredited institution for the organisation of interlaboratory studies, preparing and organizing proficiency testing schemes all over the world. Therefore, the comparison with the results provided aims to contribute to the continuous improvement of the quality of the results obtained by the CDTN. The objective of this study was to verify the reliability of the method applied two years after the intercomparison round. (author)

  15. Comparison of 2 electronic cowside tests to detect subclinical ketosis in dairy cows and the influence of the temperature and type of blood sample on the test results.

    Science.gov (United States)

    Iwersen, M; Klein-Jöbstl, D; Pichler, M; Roland, L; Fidlschuster, B; Schwendenwein, I; Drillich, M

    2013-01-01

    The objective of this study was to determine the suitability of 2 electronic hand-held devices [FreeStyle Precision (FSP), Abbott GmbH & Co. KG, Wiesbaden, Germany and GlucoMen LX Plus (GLX), A. Menarini GmbH, Vienna, Austria] for measuring β-hydroxybutyrate (BHBA) in dairy cows. Three experiments were conducted to evaluate (1) the diagnostic performance of the devices, (2) the effect of the type of blood sample, and (3) the influence of the ambient temperature on the determined results. A total of 415 blood samples from lactating Holstein and Simmental cows were collected and analyzed with both devices (whole blood) and in a laboratory (serum). Correlation coefficients between whole-blood and serum BHBA concentrations were highly significant, with 94% for the FSP and 80% for the GLX device. Based on thresholds for subclinical ketosis of 1.2 and 1.4 mmol of BHBA/L, results obtained with the hand-held devices were evaluated by receiver operating characteristics analyses. This resulted in adjusted thresholds of 1.2 and 1.4 mmol/L for the FSP and 1.1 and 1.3 mmol/L for the GLX device. Applying these thresholds, sensitivities were 98 and 100% for the FSP and 80 and 86% for the GLX device, respectively. Corresponding specificities were 90 and 97% for the FSP and 87 and 96% for the GLX device, respectively. Additionally, concentrations of BHBA were tested with both devices in whole blood, EDTA-added whole blood, and in their resulting serum and plasma, collected from 65 animals. Determined BHBA concentrations were similar within each device for whole and EDTA-added blood, and in serum and plasma, but differed between whole blood and serum and between EDTA-added blood and plasma. Blood samples with low (0.4 mmol/L), medium (1.1 mmol/L), and high (1.6 mmol/L) BHBA concentrations were stored between +5 to +32°C and analyzed repeatedly at temperature levels differing by 4°C. Additionally, devices and test strips were stored at equal conditions and used for measurement

  16. Self-Sampling for Human Papillomavirus Testing among Non-Attenders Increases Attendance to the Norwegian Cervical Cancer Screening Programme

    DEFF Research Database (Denmark)

    Enerly, Espen; Bonde, Jesper; Schee, Kristina

    2016-01-01

    Increasing attendance to screening offers the best potential for improving the effectiveness of well-established cervical cancer screening programs. Self-sampling at home for human papillomavirus (HPV) testing as an alternative to a clinical sampling can be a useful policy to increase attendance....... To determine whether self-sampling improves screening attendance for women who do not regularly attend the Norwegian Cervical Cancer Screening Programme (NCCSP), 800 women aged 25-69 years in the Oslo area who were due to receive a 2nd reminder to attend regular screening were randomly selected and invited...... were 33.4% in the intervention group and 23.2% in the control group, with similar attendance rates for both self-sampling devices. Women in the self-sampling subgroup responded favorably to both self-sampling devices and cited not remembering receiving a call for screening as the most dominant reason...

  17. Split Hopkinson Resonant Bar Test for Sonic-Frequency Acoustic Velocity and Attenuation Measurements of Small, Isotropic Geologic Samples

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, S.

    2011-04-01

    Mechanical properties (seismic velocities and attenuation) of geological materials are often frequency dependent, which necessitates measurements of the properties at frequencies relevant to a problem at hand. Conventional acoustic resonant bar tests allow measuring seismic properties of rocks and sediments at sonic frequencies (several kilohertz) that are close to the frequencies employed for geophysical exploration of oil and gas resources. However, the tests require a long, slender sample, which is often difficult to obtain from the deep subsurface or from weak and fractured geological formations. In this paper, an alternative measurement technique to conventional resonant bar tests is presented. This technique uses only a small, jacketed rock or sediment core sample mediating a pair of long, metal extension bars with attached seismic source and receiver - the same geometry as the split Hopkinson pressure bar test for large-strain, dynamic impact experiments. Because of the length and mass added to the sample, the resonance frequency of the entire system can be lowered significantly, compared to the sample alone. The experiment can be conducted under elevated confining pressures up to tens of MPa and temperatures above 100 C, and concurrently with x-ray CT imaging. The described Split Hopkinson Resonant Bar (SHRB) test is applied in two steps. First, extension and torsion-mode resonance frequencies and attenuation of the entire system are measured. Next, numerical inversions for the complex Young's and shear moduli of the sample are performed. One particularly important step is the correction of the inverted Young's moduli for the effect of sample-rod interfaces. Examples of the application are given for homogeneous, isotropic polymer samples and a natural rock sample.

  18. Sample Size Calculations for Population Size Estimation Studies Using Multiplier Methods With Respondent-Driven Sampling Surveys.

    Science.gov (United States)

    Fearon, Elizabeth; Chabata, Sungai T; Thompson, Jennifer A; Cowan, Frances M; Hargreaves, James R

    2017-09-14

    While guidance exists for obtaining population size estimates using multiplier methods with respondent-driven sampling surveys, we lack specific guidance for making sample size decisions. To guide the design of multiplier method population size estimation studies using respondent-driven sampling surveys to reduce the random error around the estimate obtained. The population size estimate is obtained by dividing the number of individuals receiving a service or the number of unique objects distributed (M) by the proportion of individuals in a representative survey who report receipt of the service or object (P). We have developed an approach to sample size calculation, interpreting methods to estimate the variance around estimates obtained using multiplier methods in conjunction with research into design effects and respondent-driven sampling. We describe an application to estimate the number of female sex workers in Harare, Zimbabwe. There is high variance in estimates. Random error around the size estimate reflects uncertainty from M and P, particularly when the estimate of P in the respondent-driven sampling survey is low. As expected, sample size requirements are higher when the design effect of the survey is assumed to be greater. We suggest a method for investigating the effects of sample size on the precision of a population size estimate obtained using multipler methods and respondent-driven sampling. Uncertainty in the size estimate is high, particularly when P is small, so balancing against other potential sources of bias, we advise researchers to consider longer service attendance reference periods and to distribute more unique objects, which is likely to result in a higher estimate of P in the respondent-driven sampling survey.

  19. Numerical study of the lateral resolution in electrostatic force microscopy for dielectric samples

    Science.gov (United States)

    Riedel, C.; Alegría, A.; Schwartz, G. A.; Colmenero, J.; Sáenz, J. J.

    2011-07-01

    We present a study of the lateral resolution in electrostatic force microscopy for dielectric samples in both force and gradient modes. Whereas previous studies have reported expressions for metallic surfaces having potential heterogeneities (Kelvin probe force microscopy), in this work we take into account the presence of a dielectric medium. We introduce a definition of the lateral resolution based on the force due to a test particle being either a point charge or a polarizable particle on the dielectric surface. The behaviour has been studied over a wide range of typical experimental parameters: tip-sample distance (1-20) nm, sample thickness (0-5) µm and dielectric constant (1-20), using the numerical simulation of the equivalent charge method. For potential heterogeneities on metallic surfaces expressions are in agreement with the bibliography. The lateral resolution of samples having a dielectric constant of more than 10 tends to metallic behaviour. We found a characteristic thickness of 100 nm, above which the lateral resolution measured on the dielectric surface is close to that of an infinite medium. As previously reported, the lateral resolution is better in the gradient mode than in the force mode. Finally, we showed that for the same experimental conditions, the lateral resolution is better for a polarizable particle than for a charge, i.e. dielectric heterogeneities should always look 'sharper' (better resolved) than inhomogeneous charge distributions. This fact should be taken into account when interpreting images of heterogeneous samples.

  20. Studies of Health Effects from Nuclear Testing near the Semipalatinsk Nuclear Test Site, Kazakhstan

    Directory of Open Access Journals (Sweden)

    Bernd Grosche

    2015-05-01

    Full Text Available The nuclear bomb testing conducted at the Semipalatinsk nuclear test site in Kazakhstan is of great importance for today’s radiation protection research, particularly in the area of low dose exposures. This type of radiation is of particular interest due to the lack of research in this field and how it impacts population health. In order to understand the possible health effects of nuclear bomb testing, it is important to determine what studies have been conducted on the effects of low dose exposure and dosimetry, and evaluate new epidemiologic data and biological material collected from populations living in proximity to the test site. With time, new epidemiological data has been made available, and it is possible that these data may be linked to biological samples. Next to linking existing and newly available data to examine health effects, the existing dosimetry system needs to be expanded and further developed to include residential areas, which have not yet been taken into account. The aim of this paper is to provide an overview of previous studies evaluating the health effects of nuclear testing, including some information on dosimetry efforts, and pointing out directions for future epidemiologic studies.

  1. Electrical perceptual threshold testing: a validation study.

    Science.gov (United States)

    Leong, Grace W S; Gorrie, Catherine A; Ng, Karl; Rutkowski, Sue; Waite, Phil M E

    2009-01-01

    To investigate inter-rater and intra-rater reliability of electrical perceptual threshold (EPT) testing in assessing somatosensory function in healthy volunteers. Prospective experimental. Hospital-based spinal cord injuries unit. Cutaneous electrical stimulation of 4 dermatomes at ASIA sensory key points (C3, T1, L3, and S2) was performed on 40 control subjects. The lowest ascending stimulus intensity at which sensation was perceived was recorded as the EPT. Mean EPT values for each dermatome, as determined by 2 testers at 2 time points, were examined and plotted against a normative template. Differences and associations between intra- and inter-rater measurements and left-right measurements were studied. EPT results for 2 people with spinal cord injuries were also examined. EPT measurements from left and right sides, obtained from the 2 time points and 2 testers, were found to be strongly associated, with the exception of left and right side measurements at the S2 dermatome. No significant differences in the mean EPT for tester or time period were found. The intra- and inter-rater reliability was good for all dermatomes tested. Mean EPT measurements fell within the range of a normative template at each of the 4 dermatomes tested. EPT is an objective, reproducible, and quantifiable method of assessing sensation in a control group. However, caution should be applied in certain dermatomes such as S2, where there was large variation between left and right side measurements.

  2. Results of Hg speciation testing on tanks 30, 32, and 37 surface samples

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-11-11

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences, Inc. in Seattle, WA on behalf of the Savannah River Remediation (SRR) Mercury Task Team.

  3. On tests of treatment-covariate interactions: An illustration of appropriate power and sample size calculations

    National Research Council Canada - National Science Library

    Gwowen Shieh

    2017-01-01

    .... Methodologically, the detection of interaction between categorical treatment levels and continuous covariate variables is analogous to the homogeneity of regression slopes test in the context of ANCOVA...

  4. Whose sample is it anyway? Widespread misannotation of samples in transcriptomics studies [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Lilah Toker

    2016-08-01

    Full Text Available Concern about the reproducibility and reliability of biomedical research has been rising. An understudied issue is the prevalence of sample mislabeling, one impact of which would be invalid comparisons. We studied this issue in a corpus of human transcriptomics studies by comparing the provided annotations of sex to the expression levels of sex-specific genes. We identified apparent mislabeled samples in 46% of the datasets studied, yielding a 99% confidence lower-bound estimate for all studies of 33%. In a separate analysis of a set of datasets concerning a single cohort of subjects, 2/4 had mislabeled samples, indicating laboratory mix-ups rather than data recording errors. While the number of mixed-up samples per study was generally small, because our method can only identify a subset of potential mix-ups, our estimate is conservative for the breadth of the problem. Our findings emphasize the need for more stringent sample tracking, and that re-users of published data must be alert to the possibility of annotation and labelling errors.

  5. Tests of Cs-137 removal from DWPF samples prior to analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dewberry, R.A.; Coleman, C.J.

    1994-11-10

    The Defense Waste Processing Facility (DWPF) will be used to encapsulate high-level radioactive waste into borosilicate glass at the Savannah River Site. To ensure that the process streams will be blended in the right proportions to produce durable glass, process control analyses will be performed in a laboratory in the DWPF. The high radioactivity of DWPF samples will require that sample preparation, including dissolution and dilution of samples, be performed in shielded cells. However the final analyses will be made with instruments and spectrometers contained in unshielded fume hoods. The primary radiation concern is the exposure to y-rays from the decay of Cs-137 after samples are removed from the shielded cells. Since there are several methods available for removing Cs-137 from samples, investigations were made into removing Cs-137 from DWPF samples prior to analysis in order to reduce worker exposure. Results are presented of the efficiency of various Cs-137 removal techniques and the effects of these techniques on analytical precision and accuracy.

  6. Results Of Hg Speciation Testing On DWPF SMECT-1, SMECT-3, And SMECT-5 Samples

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-01-07

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences, Inc. in Seattle, WA on behalf of the Savannah River Remediation (SRR) Mercury Task Team. The thirteenth shipment of samples was designated to include Defense Waste Processing Facility (DWPF) Slurry Mix Evaporator Condensate Tank (SMECT) from Sludge Receipt and Adjustment Tank (SRAT) Batch 736 and 738 samples. Triplicate samples of each material were prepared for this shipment. Each replicate was analyzed for seven Hg species: total Hg, total soluble (dissolved) Hg, elemental Hg [Hg(0)], ionic (inorganic) Hg [Hg(I) and Hg(II)], methyl Hg [CH3Hg-X, where X is a counter anion], ethyl Hg [CH3CH2-Hg-X, where X is a counter anion], and dimethyl Hg [(CH3)2Hg]. The difference between the total Hg and total soluble Hg measurements gives the particulate Hg concentration, i.e. Hg adsorbed to the surface of particulate matter in the sample but without resolution of the specific adsorbed species. The average concentrations of Hg species in the aqueous samples derived from Eurofins reported data corrected for dilutions performed by SRNL are tabulated.

  7. Testing of candidate non-lethal sampling methods for detection of Renibacterium salmoninarum in juvenile Chinook salmon Oncorhynchus tshawytscha.

    Science.gov (United States)

    Elliott, Diane G; McKibben, Constance L; Conway, Carla M; Purcell, Maureen K; Chase, Dorothy M; Applegate, LynnMarie J

    2015-05-11

    Non-lethal pathogen testing can be a useful tool for fish disease research and management. Our research objectives were to determine if (1) fin clips, gill snips, surface mucus scrapings, blood draws, or kidney biopsies could be obtained non-lethally from 3 to 15 g Chinook salmon Oncorhynchus tshawytscha, (2) non-lethal samples could accurately discriminate between fish exposed to the bacterial kidney disease agent Renibacterium salmoninarum and non-exposed fish, and (3) non-lethal samples could serve as proxies for lethal kidney samples to assess infection intensity. Blood draws and kidney biopsies caused ≥5% post-sampling mortality (Objective 1) and may be appropriate only for larger fish, but the other sample types were non-lethal. Sampling was performed over 21 wk following R. salmoninarum immersion challenge of fish from 2 stocks (Objectives 2 and 3), and nested PCR (nPCR) and real-time quantitative PCR (qPCR) results from candidate non-lethal samples were compared with kidney tissue analysis by nPCR, qPCR, bacteriological culture, enzyme-linked immunosorbent assay (ELISA), fluorescent antibody test (FAT) and histopathology/immunohistochemistry. R. salmoninarum was detected by PCR in >50% of fin, gill, and mucus samples from challenged fish. Mucus qPCR was the only non-lethal assay exhibiting both diagnostic sensitivity and specificity estimates>90% for distinguishing between R. salmoninarum-exposed and non-exposed fish and was the best candidate for use as an alternative to lethal kidney sample testing. Mucus qPCR R. salmoninarum quantity estimates reflected changes in kidney bacterial load estimates, as evidenced by significant positive correlations with kidney R. salmoninarum infection intensity scores at all sample times and in both fish stocks, and were not significantly impacted by environmental R. salmoninarum concentrations.

  8. Testing of candidate non-lethal sampling methods for detection of Renibacterium salmoninarum in juvenile Chinook salmon Oncorhynchus tshawytscha

    Science.gov (United States)

    Elliott, Diane G.; McKibben, Constance L.; Conway, Carla M.; Purcell, Maureen K.; Chase, Dorothy M.; Applegate, Lynn M.

    2015-01-01

    Non-lethal pathogen testing can be a useful tool for fish disease research and management. Our research objectives were to determine if (1) fin clips, gill snips, surface mucus scrapings, blood draws, or kidney biopsies could be obtained non-lethally from 3 to 15 g Chinook salmon Oncorhynchus tshawytscha, (2) non-lethal samples could accurately discriminate between fish exposed to the bacterial kidney disease agent Renibacterium salmoninarum and non-exposed fish, and (3) non-lethal samples could serve as proxies for lethal kidney samples to assess infection intensity. Blood draws and kidney biopsies caused ≥5% post-sampling mortality (Objective 1) and may be appropriate only for larger fish, but the other sample types were non-lethal. Sampling was performed over 21 wk following R. salmoninarum immersion challenge of fish from 2 stocks (Objectives 2 and 3), and nested PCR (nPCR) and real-time quantitative PCR (qPCR) results from candidate non-lethal samples were compared with kidney tissue analysis by nPCR, qPCR, bacteriological culture, enzyme-linked immunosorbent assay (ELISA), fluorescent antibody test (FAT) and histopathology/immunohistochemistry. R. salmoninarum was detected by PCR in >50% of fin, gill, and mucus samples from challenged fish. Mucus qPCR was the only non-lethal assay exhibiting both diagnostic sensitivity and specificity estimates >90% for distinguishing between R. salmoninarum-exposed and non-exposed fish and was the best candidate for use as an alternative to lethal kidney sample testing. Mucus qPCR R. salmoninarum quantity estimates reflected changes in kidney bacterial load estimates, as evidenced by significant positive correlations with kidney R. salmoninaruminfection intensity scores at all sample times and in both fish stocks, and were not significantly impacted by environmentalR. salmoninarum concentrations.

  9. Study of an RF Direct Sampling Technique for Geodetic VLBI

    Science.gov (United States)

    Takefuji, K.; Kondo, T.; Sekido, M.; Ichikawa, R.; Kurihara, S.; Kokado, K.; Kawabata, R.

    2012-12-01

    Recently some digital samplers, which involve high RF frequency sensitivity, have been developed. We installed such samplers (sensitivity up to 24 GHz) at the Kashima 11-m station and the Tsukuba 32-m station (about 50 km baseline) in Japan and directly sampled X-band without any frequency conversion such as analog mixers. After the correlation process, we successfully detected first fringes at X-band. For the purpose of observing geodetic VLBI, we mixed signals of the S-band and the X-band just after the low noise amplifier. The mixed signal became overlapped and aliased baseband signals after 1024 MHz, 2-bit sampling. We could obtain four fringes (one from S-band and three from X-band), which came from the overlapped baseband signals, and successfully determined the baseline length.

  10. Evaluation of a New Device for Simplifying and Standardizing Stool Sample Preparation for Viral Molecular Testing with Limited Hands-On Time

    OpenAIRE

    Feghoul, Linda; Salmona, Maud; Cherot, Janine; Fahd, Mony; Dalle, Jean-Hugues; Vachon, Carole; Perrod, Aurélie; Bourgeois, Philippe; Scieux, Catherine; Baruchel, André; Simon, François; Legoff, Jérôme

    2016-01-01

    Sensitive molecular assays have greatly improved the diagnosis of viral gastroenteritis. However, the proper preparation of stool samples for clinical testing remains an issue. bioMérieux has developed a stool preprocessing device (SPD) that includes a spoon for calibrated sampling and a vial containing buffer, glass beads, and two filters. The resulting stool filtrate is used for nucleic acid extraction. The purpose of this study was to evaluate the performance of the SPD for the quantificat...

  11. Multiwavelength studies of X-ray selected extragalactic sample

    OpenAIRE

    Mickaelian, A. M.; Paronyan, G. M.; Harutyunyan, G. S.; Abrahamyan, H. V.; Gyulzadyan, M. V.

    2015-01-01

    The joint catalogue of Active Galactic Nuclei selected from optical identifications of X-ray sources was created as a combination of two samples: Hamburg-ROSAT Catalogue (HRC) and Byurakan-Hamburg-ROSAT Catalogue (BHRC). Both are based on optical identifications of X-ray sources from ROSAT catalogues using low-dispersion spectra of Hamburg Quasar Survey (HQS). However, HRC and BHRC contain a number of misidentifications and using the recent optical and multiwavelength (MW) catalogues we have ...

  12. Chemical analysis of water samples and geophysical logs from cored test holes drilled in the central Oklahoma Aquifer, Oklahoma

    Science.gov (United States)

    Schlottmann, Jamie L.; Funkhouser, Ron A.

    1991-01-01

    Chemical analyses of water from eight test holes and geophysical logs for nine test holes drilled in the Central Oklahoma aquifer are presented. The test holes were drilled to investigate local occurrences of potentially toxic, naturally occurring trace substances in ground water. These trace substances include arsenic, chromium, selenium, residual alpha-particle activities, and uranium. Eight of the nine test holes were drilled near wells known to contain large concentrations of one or more of the naturally occurring trace substances. One test hole was drilled in an area known to have only small concentrations of any of the naturally occurring trace substances.Water samples were collected from one to eight individual sandstone layers within each test hole. A total of 28 water samples, including four duplicate samples, were collected. The temperature, pH, specific conductance, alkalinity, and dissolved-oxygen concentrations were measured at the sample site. Laboratory determinations included major ions, nutrients, dissolved organic carbon, and trace elements (aluminum, arsenic, barium, beryllium, boron, cadmium, chromium, hexavalent chromium, cobalt, copper, iron, lead, lithium, manganese, mercury, molybdenum, nickel, selenium, silver, strontium, vanadium and zinc). Radionuclide activities and stable isotope (5 values also were determined, including: gross-alpha-particle activity, gross-beta-particle activity, radium-226, radium-228, radon-222, uranium-234, uranium-235, uranium-238, total uranium, carbon-13/carbon-12, deuterium/hydrogen-1, oxygen-18/oxygen-16, and sulfur-34/sulfur-32. Additional analyses of arsenic and selenium species are presented for selected samples as well as analyses of density and iodine for two samples, tritium for three samples, and carbon-14 for one sample.Geophysical logs for most test holes include caliper, neutron, gamma-gamma, natural-gamma logs, spontaneous potential, long- and short-normal resistivity, and single-point resistance

  13. Chemical analysis of water samples and geophysical logs from cored test holes drilled in the central Oklahoma Aquifer, Oklahoma

    Science.gov (United States)

    Schlottmann, Jamie L.; Funkhouser, Ron A.

    1991-01-01

    Chemical analyses of water from eight test holes and geophysical logs for nine test holes drilled in the Central Oklahoma aquifer are presented. The test holes were drilled to investigate local occurrences of potentially toxic, naturally occurring trace substances in ground water. These trace substances include arsenic, chromium, selenium, residual alpha-particle activities, and uranium. Eight of the nine test holes were drilled near wells known to contain large concentrations of one or more of the naturally occurring trace substances. One test hole was drilled in an area known to have only small concentrations of any of the naturally occurring trace substances. Water samples were collected from one to eight individual sandstone layers within each test hole. A total of 28 water samples, including four duplicate samples, were collected. The temperature, pH, specific conductance, alkalinity, and dissolved-oxygen concentrations were measured at the sample site. Laboratory determinations included major ions, nutrients, dissolved organic carbon, and trace elements (aluminum, arsenic, barium, beryllium, boron, cadmium, chromium, hexavalent chromium, cobalt, copper, iron, lead, lithium, manganese, mercury, molybdenum, nickel, selenium, silver, strontium, vanadium, and zinc). Radionuclide activities and stable isotope d values also were determined, including: gross-alpha-particle activity, gross-beta-particle activity, radium-226, radium-228, radon-222, uranium-234, uranium-235, uranium-238, total uranium, carbon-13/carbon-12, deuterium/hydrogen-1, oxygen-18/oxygen-16, and sulfur-34/sulfur-32. Additional analyses of arsenic and selenium species are presented for selected samples as well as analyses of density and iodine for two samples, tritium for three samples, and carbon-14 for one sample. Geophysical logs for most test holes include caliper, neutron, gamma-gamma, natural-gamma logs, spontaneous potential, long- and short-normal resistivity, and single-point resistance

  14. Conditional and Unconditional Tests (and Sample Size Based on Multiple Comparisons for Stratified 2 × 2 Tables

    Directory of Open Access Journals (Sweden)

    A. Martín Andrés

    2015-01-01

    Full Text Available The Mantel-Haenszel test is the most frequent asymptotic test used for analyzing stratified 2 × 2 tables. Its exact alternative is the test of Birch, which has recently been reconsidered by Jung. Both tests have a conditional origin: Pearson’s chi-squared test and Fisher’s exact test, respectively. But both tests have the same drawback that the result of global test (the stratified test may not be compatible with the result of individual tests (the test for each stratum. In this paper, we propose to carry out the global test using a multiple comparisons method (MC method which does not have this disadvantage. By refining the method (MCB method an alternative to the Mantel-Haenszel and Birch tests may be obtained. The new MC and MCB methods have the advantage that they may be applied from an unconditional view, a methodology which until now has not been applied to this problem. We also propose some sample size calculation methods.

  15. Empirical validation of the CRAFFT Abuse Screening Test in a Spanish sample.

    Science.gov (United States)

    Rial, Antonio; Kim-Harris, Sion; Knight, John R; Araujo, Manuel; Gómez, Patricia; Braña, Teresa; Varela, Jesús; Golpe, Sandra

    2018-01-15

    The CRAFFT Substance Abuse Screening Instrument, developed by the Center for Adolescents Substance Abuse Research (CeASAR) (Knight et al., 1999), is a screening tool for high-risk alcohol and drug risk consumption designed for use with adolescents. Since its publication it has been the subject of translations and validations in different countries, populations and contexts that have demonstrated its enormous potential. However, there is still no empirical validation study that would ensure its good psychometric performance in Spain. The aim of this paper is to develop an adapted version of the CRAFFT in Spanish and to analyze its psychometric properties in a sample of Spanish adolescents. For this purpose an individual interview was conducted on 312 adolescents aged between 12 and 18 years of age (M = 15.01; SD = 1.83) from the Galician community. The interview included a part of the Adolescent Diagnostic Interview (ADI) and the Problem Oriented Screening Instrument for Teenagers (POSIT). The results obtained, similar to those found in other countries, allow us to report that the Spanish version of the CRAFFT has a good psychometric behaviorproperties. It was found to have a satisfactory internal consistency with a Cronbach’s alpha value of .74. In terms of sensitivity and specificity, values of 74.4% and 96.4% respectively, were obtained and the area under the ROC curve was .946. The Spanish version of the CRAFFT is made available to researchers and professionals in the field of addictive behaviors, so that it can be used with the necessary psychometric guarantees.

  16. Advanced Demonstration and Test Reactor Options Study

    Energy Technology Data Exchange (ETDEWEB)

    Petti, David Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hill, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Gehin, J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gougar, Hans David [Idaho National Lab. (INL), Idaho Falls, ID (United States); Strydom, Gerhard [Idaho National Lab. (INL), Idaho Falls, ID (United States); Heidet, F. [Argonne National Lab. (ANL), Argonne, IL (United States); Kinsey, J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Grandy, Christopher [Argonne