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Selected AbstractsSperm function tests and fertilityINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2006R. J. Aitken Summary Traditionally, the diagnosis of male infertility has depended upon a descriptive evaluation of human semen with emphasis on the number of spermatozoa that are present in the ejaculate, their motility and their morphology. The fundamental tenet underlying this approach is that male fertility can be defined by reference to a threshold concentration of motile, morphologically normal spermatozoa that must be exceeded in order to achieve conception. Many independent studies have demonstrated that this fundamental concept is flawed and, in reality, it is not so much the absolute number of spermatozoa that determines fertility, but their functional competence. In the light of this conclusion, a range of in vitro tests have been developed to monitor various aspects of sperm function including their potential for movement, cervical mucus penetration, capacitation, zona recognition, the acrosome reaction and sperm,oocyte fusion. Such functional assays have been found to predict the fertilizing capacity of human spermatozoa in vitro and in vivo with some accuracy. Recent developments in this field include the introduction of tests to assess the degree to which human spermatozoa have suffered oxidative stress as well as the integrity of their nuclear and mitochondrial DNA. Such assessments not only yield information on the fertilizing capacity of human spermatozoa but also their ability to support normal embryonic development. [source] Reliability and Attribute-Based Scoring in Cognitive Diagnostic AssessmentJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 3 2009Mark J. Gierl The attribute hierarchy method (AHM) is a psychometric procedure for classifying examinees' test item responses into a set of structured attribute patterns associated with different components from a cognitive model of task performance. Results from an AHM analysis yield information on examinees' cognitive strengths and weaknesses. Hence, the AHM can be used for cognitive diagnostic assessment. The purpose of this study is to introduce and evaluate a new concept for assessing attribute reliability using the ratio of true score variance to observed score variance on items that probe specific cognitive attributes. This reliability procedure is evaluated and illustrated using both simulated data and student response data from a sample of algebra items taken from the March 2005 administration of the SAT. The reliability of diagnostic scores and the implications for practice are also discussed. [source] Viewing Spatial Consequences of Budgetary Policy ChangesPUBLIC BUDGETING AND FINANCE, Issue 2 2005Robert T. Greenbaum While the research community is often very concerned with the distributional effect of public policy decisions, the geographic distribution of the affected populations is often overlooked. This paper argues that seemingly geographically neutral policies have spatial consequences and that the choice of how to measure them is important. We suggest that maps provide a powerful tool for communicating these ideas to policy makers and that geographical information systems supplemented by spatial statistics yield information that assist policy debates. We develop metrics to illustrate how geographic information provides insights into the spatial consequences of Medicaid expenditure changes in Ohio. [source] A stable isotope record from freshwater lake shells of the eastern Tibetan Plateau, China, during the past two centuriesBOREAS, Issue 1 2007JINGLU WU Wu, J. L., Schleser, G. H., Lücke, A. & Li, S. 2007 (January): A stable isotope record from freshwater lake shells of the eastern Tibetan Plateau, China, during the past two centuries. Boreas, Vol. 36, pp. 38,46. Oslo. ISSN 0300,9483. Lake Xingcuo is a small, closed, hardwater lake situated in the eastern Tibetan Plateau. Stable isotope data (,18O and ,13C) from the freshwater snail Gyraulus sibirica (Dunker) in a 34-cm-long, radioactive isotope-dated sediment core represent the past 200 years of Lake Xingcuo environmental history. Carbon and oxygen isotope ratios in the shells of the snail yield information on the isotopic composition of the water in which the shell was formed, which in turn relates to climatic conditions prevailing during the snail's life-span. Living and fossil shells from Lake Xingcuo were collected. ,18O values in the living shells from Lake Xingcuo are in equilibrium with ambient waters, while ,13C values may trace snail dietary carbon. On comparing ,18O and ,13C in the shell of Gyraulus sibirica with monitored data for the period 1954,1995, we found that the ,18O composition in the shell is an efficient proxy revealing air temperature during the warmer months from April to September. There is a positive correlation between the ,18O in the shells of Gyraulus sibirica and the running average temperature of the warmer months. Climatic variability in the eastern Tibetan Plateau for the past two centuries has been inferred from the ,18O record from the freshwater snails in the sediments of Lake Xingcuo. As such, the last 200 years' palaeoclimatic record for this region can be separated into three periods representing oscillations between warm and cool conditions consistent with the Guliya ice record in the Tibetan Plateau. [source] Housing anxiety and multiple geographies in post-tsunami Sri LankaDISASTERS, Issue 4 2009Camillo Boano Tsunami intervention has been an extraordinary and unprecedented relief and recovery operation. This article underlines the complexities posed by shelter and housing intervention in post-tsunami Sri Lanka, revealing a pragmatic, reductionist approach to shelter and housing reconstruction in a contested and fragmented environment. Competition, housing anxiety and buffer zone implementation have resulted in compulsory villagisation inland, stirring feelings of discrimination and tension, and becoming major obstacles to equitable rebuilding of houses and livelihoods. A new tsunami geography has been imposed on an already vulnerable conflict-based geography, in which shelter has been conceived as a mono-dimensional artefact. An analysis of the process and outcomes of temporary and permanent post-tsunami housing programmes yields information about the extent to which shelter policies and programmes serve not only physical needs but ,higher order' objectives for a comprehensive and sustainable recovery plan. [source] Fish movement and habitat use depends on water body size and shapeECOLOGY OF FRESHWATER FISH, Issue 1 2009D. A. Woolnough Abstract,,, Home ranges are central to understanding habitat diversity, effects of fragmentation and conservation. The distance that an organism moves yields information on life history, genetics and interactions with other organisms. Present theory suggests that home range is set by body size of individuals. Here, we analyse estimates of home ranges in lakes and rivers to show that body size of fish and water body size and shape influence home range size. Using 71 studies including 66 fish species on five continents, we show that home range estimates increased with increasing water body size across water body shapes. This contrasts with past studies concluding that body size sets home range. We show that water body size was a consistently significant predictor of home range. In conjunction, body size and water body size can provide improved estimates of home range than just body size alone. As habitat patches are decreasing in size worldwide, our findings have implications for ecology, conservation and genetics of populations in fragmented ecosystems. [source] The stress response is repressed during fermentation in brewery strains of yeastJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2000M.P. Brosnan Yeast cells encounter a variety of environmental stresses during brewing and must respond to ensure cell survival. Cells can respond to stress by inducing a Heat Shock Response in which heat shock proteins (Hsps) are synthesized. In laboratory strains of Saccharomyces cerevisiae, the heat shock protein, Hsp104, plays a major role in the acquisition of tolerance to a variety of stresses such as heat, ethanol and sodium arsenite, and as such acts as an excellent stress indicator. The induction of Hsp104 in bottom-and top-fermenting brewery strains was examined when grown under laboratory and industrial fermentation conditions, and it was found that each brewing strain exhibits its own unique pattern of Hsp104 expression. During industrial fermentations, brewery strains are capable of mounting a stress response at the early stages of fermentation. However, as the fermentation proceeds, the response is repressed. The results suggest that conditions experienced in industrial brewing prevent the activation of the stress response. This study increases our understanding of alterations in gene expression patterns during the brewing process, and yields information that will aid in the definition of best practice in yeast management. [source] Specific and non-specific solvent effects on aromatic nucleophilic substitution.JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 5 20026-dinitrobenzene, Kinetics of the reaction of 1-fluoro-, homopiperidine in binary solvent mixtures Abstract This paper presents a comparative study of the solvent effects on the kinetics of the reactions between 1-fluoro-2,6-dinitrobenzene and hexahydro-1H -azepine in ethyl acetate,+,chloroform or acetonitrile and acetonitrile,+,chloroform binary solvent mixtures. The purpose was to asses the contribution of each molecular-microscopic solvent property to the overall solvation effect of the reaction critical state. The influence of the dipolarity/polarizability, hydrogen-bond donor acidity and hydrogen-bond acceptor basicity of the solvent mixtures on the reaction rate was analyzed by the application of the multiparametric approach of Kamlet, Abboud and Taft. The evaluation of the correlation coefficients shows that the solvation effects are dominated by the non-specific interactions. Moreover, the incidence of the hydrogen-bond acceptor solvent ability is more important than that corresponding to the hydrogen-bond donor character, except for the reactions that manifest kinetic retarding effects. The influence of the solvation effects on the base catalysis was analyzed, describing the response patterns of the partial rate coefficients to the mixture composition and also to each solvent property. The application of a preferential solvation model to the kinetic results yields information on the preferential solvation of the reaction critical state by any of the pure solvents, or by the hydrogen-bonded complexed media. Copyright © 2002 John Wiley & Sons, Ltd. [source] A standard test for AGCMs including their physical parametrizations.ATMOSPHERIC SCIENCE LETTERS, Issue 2 2000II: results for the Met Office Model Abstract Example results are shown for the proposed aqua-planet experiments using a version of The Met Office Unified Model (UM). The zonal mean circulation exhibits strong sensitivity to the latitudinal distribution of sea-surface temperatures (SST). Longitudinal variation of SST yields information on the linearity and distribution of the convective response. Copyright © 2001 Royal Meteorological Society. [source] | |||||||||||||