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Various Tests (various + test)
Selected AbstractsAlcohol and hypertension: gender differences in dose,response relationships determined through systematic review and meta-analysisADDICTION, Issue 12 2009Benjamin Taylor ABSTRACT Aims To analyze the dose,response relationship between average daily alcohol consumption and the risk of hypertension via systematic review and meta-analysis. Design A computer-assisted search was completed for 10 databases, followed by hand searches of relevant articles. Only studies with longitudinal design, quantitative measurement of alcohol consumption and biological measurement of outcome were included. Dose,response relationships were assessed by determining the best-fitting model via first- and second-degree fractional polynomials. Various tests for heterogeneity and publication bias were conducted. Findings A total of 12 cohort studies were identified from the literature from the United States, Japan and Korea. A linear dose,response relationship with a relative risk of 1.57 at 50 g pure alcohol per day and 2.47 at 100 g per day was seen for men. Among women, the meta-analysis indicated a more modest protective effect than reported previously: a significant protective effect was reported for consumption at or below about 5 g per day, after which a linear dose,response relationship was found with a relative risk of 1.81 at 50 g per day and of 2.81 at an average daily consumption of 100 g pure alcohol per day. Among men, Asian populations had higher risks than non-Asian populations. Conclusions The risk for hypertension increases linearly with alcohol consumption, so limiting alcohol intake should be advised for both men and women. [source] Design and Control of a Four-Wheeled Omnidirectional Mobile Robot with Steerable Omnidirectional WheelsJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 4 2004Jae-Bok Song Omnidirectional mobile robots are capable of arbitrary motion in an arbitrary direction without changing the direction of wheels, because they can perform 3 degree-of-freedom (DOF) motion on a two-dimensional plane. In this research, a new class of omnidirectional mobile robot is proposed. Since it has synchronously steerable omnidirectional wheels, it is called an omnidirectional mobile robot with steerable omnidirectional wheels (OMR-SOW). It has 3 DOFs in motion and one DOF in steering. One steering DOF can function as a continuously variable transmission (CVT). CVT of the OMR-SOW increases the range of velocity ratio from the wheel velocities to robot velocity, which may improve performance of the mobile robot. The OMR-SOW with four omnidirectional wheels has been developed in this research. Kinematics and dynamics of this robot will be analyzed in detail. Various tests have been conducted to demonstrate the validity and feasibility of the proposed mechanism and control algorithm. © 2004 Wiley Periodicals, Inc. [source] An inherently mass-conserving semi-implicit semi-Lagrangian discretisation of the shallow-water equations on the sphereTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 642 2009M. Zerroukat Abstract For the shallow-water equations on the sphere, an inherently mass-conserving semi-Lagrangian discretisation (SLICE) of the continuity equation is coupled with a semi-implicit semi-Lagrangian discretisation of the momentum equations. Various tests from the literature (two with analytical nonlinear solutions) are used to assess the model's performance and also to compare it with that of a variant model that instead employs a standard non-conserving semi-implicit semi-Lagrangian discretisation of the continuity equation. The mass-conserving version gives results that are overall somewhat better than the non-conserving one. Copyright © 2009 Royal Meteorological Society and Crown Copyright [source] Forensic evaluation of clothing flammabilityFIRE AND MATERIALS, Issue 7 2009M. M. Hirschler Abstract A set of 17 commercial garments were purchased, categorized based on their fabric composition and fire tested. Three fire exposures were used: (a) a simile of the United States regulatory test for apparel fabrics (16CFR1610), (b) a small vertical candle on a small swatch of fabric and (c) a candle applied to a full garment, placed on a mannequin. Comparisons were made between the results of the various tests and of the various fabrics tested. A general correlation was observed whereby increased fabric areal density [weight/unit fabric area] resulted in improved fire performance. Where outliers to this generalization were observed the improved fire performance was due to the superior inherent fire performance of specific fabric types such as silk. Overall, the quantitative behavior with regard to flame spread rate observed after ignition of cellulosic, thermoplastic and blended fabrics was more heavily dependent on fabric areal density than on their chemical composition. Two key conclusions are that very lightweight fabrics constitute a potential danger and that the United States regulatory value, set at 88.3g/m2 (2.6oz/yd2), represents an essentially arbitrary cut-off in this regard. Copyright © 2009 John Wiley & Sons, Ltd. [source] Hypolocomotion, anxiety and serotonin syndrome-like behavior contribute to the complex phenotype of serotonin transporter knockout miceGENES, BRAIN AND BEHAVIOR, Issue 4 2007A. V. Kalueff Although mice with a targeted disruption of the serotonin transporter (SERT) have been studied extensively using various tests, their complex behavioral phenotype is not yet fully understood. Here we assess in detail the behavior of adult female SERT wild type (+/+), heterozygous (+/,) and knockout (,/,) mice on an isogenic C57BL/6J background subjected to a battery of behavioral paradigms. Overall, there were no differences in the ability to find food or a novel object, nest-building, self-grooming and its sequencing, and horizontal rod balancing, indicating unimpaired sensory functions, motor co-ordination and behavioral sequencing. In contrast, there were striking reductions in exploration and activity in novelty-based tests (novel object, sticky label and open field tests), accompanied by pronounced thigmotaxis, suggesting that combined hypolocomotion and anxiety (rather than purely anxiety) influence the SERT ,/, behavioral phenotype. Social interaction behaviors were also markedly reduced. In addition, SERT ,/, mice tended to move close to the ground, frequently displayed spontaneous Straub tail, tics, tremor and backward gait , a phenotype generally consistent with ,serotonin syndrome'-like behavior. In line with replicated evidence of much enhanced serotonin availability in SERT ,/, mice, this serotonin syndrome-like state may represent a third factor contributing to their behavioral profile. An understanding of the emerging complexity of SERT ,/, mouse behavior is crucial for a detailed dissection of their phenotype and for developing further neurobehavioral models using these mice. [source] Nonlinear Alternatives to Unit Root Tests and Public Finances Sustainability: Some Evidence from Latin American and Caribbean Countries,OXFORD BULLETIN OF ECONOMICS & STATISTICS, Issue 5 2008Georgios Chortareas Abstract We analyse the sustainability of government debt for Latin American and Caribbean countries employing unit-root tests with nonlinear alternative hypotheses and examine the robustness of our results against those from unit-root tests with breaks and threshold nonlinearities. We show that, in general support for sustainability substantially improves when nonlinear mean reversion is taken into account. We also find that the results obtained from applying various tests with nonlinear alternatives, although broadly consistent, are not identical. This suggests that reliance on a single unit-root test for assessing fiscal policy sustainability may be misleading. [source] A comparison of measures of disproportionality for signal detection in spontaneous reporting systems for adverse drug reactionsPHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 1 2002Eugéne P. van Puijenbroek Abstract Purpose A continuous systematic review of all combinations of drugs and suspected adverse reactions (ADRs) reported to a spontaneous reporting system, is necessary to optimize signal detection. To focus attention of human reviewers, quantitative procedures can be used to sift data in different ways. In various centres, different measures are used to quantify the extent to which an ADR is reported disproportionally to a certain drug compared to the generality of the database. The objective of this study is to examine the level of concordance of the various estimates to the measure used by the WHO Collaborating Centre for International ADR monitoring, the information component (IC), when applied to the dataset of the Netherlands Pharmacovigilance Foundation Lareb. Methods The Reporting Odds Ratio,1.96 standard errors (SE), proportional reporting ratio,1.96 SE, Yule's Q,1.96,SE, the Poisson probability and Chi-square test of all 17,330 combinations were compared with the IC minus 2 standard deviations. Additionally, the concordance of the various tests, in respect to the number of reports per combination, was examined. Results In general, sensitivity was high in respect to the reference measure when a combination of point- and precision estimate was used. The concordance increased dramatically when the number of reports per combination increased. Conclusion This study shows that the different measures used are broadly comparable when four or more cases per combination have been collected. Copyright © 2001 John Wiley & Sons, Ltd. [source] Modeling the effects of health status and the educational infrastructure on the cognitive development of Tanzanian schoolchildrenAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2005Alok Bhargava This paper models the proximate determinants of school attendance and scores on cognitive and educational achievement tests and on school examinations of over 600 schoolchildren from the Control group of a randomized trial in Tanzania, where children in the Intervention group heavily infected with hookworm and schistosomiasis received treatment. The modeling approach used a random effects framework and incorporated the inter-relationships between school attendance and performance on various tests, controlling for children's health status, socioeconomic variables, grade level, and the educational infrastructure. The empirical results showed the importance of variables such as children's height and hemoglobin concentration for the scores, especially on educational achievement tests that are easy to implement in developing countries. Also, teacher experience and work assignments were significant predictors of the scores on educational achievement tests, and there was some evidence of multiplicative effects of children's heights and work assignments on the test scores. Lastly, some comparisons were made for changes in test scores of treated children in the Intervention group with the untreated children in the Control group. Am. J. Hum. Biol. 17:280,292, 2005. © 2005 Wiley-Liss, Inc. [source] Two-sample Comparison Based on Prediction Error, with Applications to Candidate Gene Association StudiesANNALS OF HUMAN GENETICS, Issue 1 2007K. Yu Summary To take advantage of the increasingly available high-density SNP maps across the genome, various tests that compare multilocus genotypes or estimated haplotypes between cases and controls have been developed for candidate gene association studies. Here we view this two-sample testing problem from the perspective of supervised machine learning and propose a new association test. The approach adopts the flexible and easy-to-understand classification tree model as the learning machine, and uses the estimated prediction error of the resulting prediction rule as the test statistic. This procedure not only provides an association test but also generates a prediction rule that can be useful in understanding the mechanisms underlying complex disease. Under the set-up of a haplotype-based transmission/disequilibrium test (TDT) type of analysis, we find through simulation studies that the proposed procedure has the correct type I error rates and is robust to population stratification. The power of the proposed procedure is sensitive to the chosen prediction error estimator. Among commonly used prediction error estimators, the .632+ estimator results in a test that has the best overall performance. We also find that the test using the .632+ estimator is more powerful than the standard single-point TDT analysis, the Pearson's goodness-of-fit test based on estimated haplotype frequencies, and two haplotype-based global tests implemented in the genetic analysis package FBAT. To illustrate the application of the proposed method in population-based association studies, we use the procedure to study the association between non-Hodgkin lymphoma and the IL10 gene. [source] | ||||||||||||||||