166 research outputs found

    Determinants of Student Performance in an Undergraduate Financial Accounting Class

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    This study investigates the effects of class size, high school accounting, aptitude and attitude on learning , measured by the difference between post-test and pre-test scores, in an undergraduate financial accounting class, after controlling for students' major and semester level. Statistical analysis showed that scores of students in small classes improved by 48%, while scores of students in the large classes improved by 6% percent, implying a decline in learning by 88% by shifting to larger classes. High school accounting was found to improve pre- and post-test scores but the improvement on their post-test scores was significantly lower, implying a diminishing effect of high school accounting on performance as the complexity of the course material increases. We also found that midterm grade (aptitude) and changes in perception about the relevance of the class on business-related issues (attitude) motivate learning.Teaching/Communication/Extension/Profession,

    Genetic improvement of meat quality and fertility using the national nucleus

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    Knowledge is power and the National Swine Registry (NSR) is the only source of complete, publicly available, genetic records on nucleus populations. NSR has offered STAGES \u27, a BLUP genetic improvement program with bio-economic indexes for over 17 years. NSR members submit information on 3 sow productivity traits and 3 postweaning performance traits and in return receive across-herd Expected Progeny Deviations (EPDs) for these traits along with indexes for Sow Productivity, Maternal Line (sow productivity and postweaning performance) and Terminal (postweaning traits only) to be used in genetic selection. Not only is this genetic information available to members but genetic values and trends for these traits are also available to any commercial producer or genetic advisor. This program has led NSR members to make substantial genetic improvement for these traits within all four breeds. In addition, this transparent system allows commercial producers to design programs and select animals that allow them the greatest potential for their situation. As the pork industry continues ro change, multiple pork chains are forming to meets distinct specifications desired by subsets of consumers. To continue to meet the demand of these dissimilar pork chains, differentiated genetic lines are necessary to provide products that match their specifications. In addition, as profit per pig continues to decline pork producers must be able to increase product sold per unit of investment. To facilitate this key profitability indicator, the fertility of breeding females must improve. To address these two key drivers in today\u27s pork industry, the NSR has updated their genetic improvement program in these two areas

    Abundance and local - scale processes contribute to multi-phyla gradients in global marine diversity

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    Among themost enduring ecological challenges is an integrated theory explaining the latitudinal biodiversity gradient, including discrepancies observed at different spatial scales. Analysis of Reef Life Survey data for 4127 marine species at 2406 coral and rocky sites worldwide confirms that the total ecoregion richness peaks in low latitudes, near +15°N and −15°S. However, although richness at survey sites ismaximal near the equator for vertebrates, it peaks at high latitudes for large mobile invertebrates. Site richness for different groups is dependent on abundance, which is in turn correlated with temperature for fishes and nutrients for macroinvertebrates. We suggest that temperature-mediated fish predation and herbivory have on strained mobile macroinvertebrate diversity at the site scale across the tropics. Conversely, at the ecoregion scale, richness responds positively to coral reef area, highlighting potentially huge global biodiversity losses with coral decline. Improved conservation outcomes require management frameworks, informed by hierarchical monitoring, that cover differing site- and regional-scale processes across diverse taxa, including attention to invertebrate species, which appear disproportionately threatened by warming seas

    Anthropogenic disruptions to longstanding patterns of trophic-size structure in vertebrates

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    Diet and body mass are inextricably linked in vertebrates: while herbivores and carnivores have converged on much larger sizes, invertivores and omnivores are, on average, much smaller, leading to a roughly U-shaped relationship between body size and trophic guild. Although this U-shaped trophic-size structure is well documented in extant terrestrial mammals, whether this pattern manifests across diverse vertebrate clades and biomes is unknown. Moreover, emergence of the U-shape over geological time and future persistence are unknown. Here we compiled a comprehensive dataset of diet and body size spanning several vertebrate classes and show that the U-shaped pattern is taxonomically and biogeographically universal in modern vertebrate groups, except for marine mammals and seabirds. We further found that, for terrestrial mammals, this U-shape emerged by the Palaeocene and has thus persisted for at least 66 million years. Yet disruption of this fundamental trophic-size structure in mammals appears likely in the next century, based on projected extinctions. Actions to prevent declines in the largest animals will sustain the functioning of Earth's wild ecosystems and biomass energy distributions that have persisted through deep time

    No-Boundary Thinking in Bioinformatics Research

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    Currently there are definitions from many agencies and research societies defining bioinformatics as deriving knowledge from computational analysis of large volumes of biological and biomedical data. Should this be the bioinformatics research focus? We will discuss this issue in this review article. We would like to promote the idea of supporting human-infrastructure (HI) with no-boundary thinking (NT) in bioinformatics (HINT)

    VEGF-A165b is an endogenous neuroprotective splice isoform of vascular endothelial growth factor A in vivo and in vitro

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    Vascular endothelial growth factor (VEGF) A is generated as two isoform families by alternative RNA splicing, represented by VEGF-A165a and VEGF-A165b. These isoforms have opposing actions on vascular permeability, angiogenesis, and vasodilatation. The proangiogenic VEGF-A165a isoform is neuroprotective in hippocampal, dorsal root ganglia, and retinal neurons, but its propermeability, vasodilatatory, and angiogenic properties limit its therapeutic usefulness. In contrast, a neuroprotective effect of endogenous VEGF-A165b on neurons would be advantageous for neurodegenerative pathologies. Endogenous expression of human and rat VEGF-A165b was detected in hippocampal and cortical neurons. VEGF-A165b formed a significant proportion of total VEGF-A in rat brain. Recombinant human VEGF-A165b exerted neuroprotective effects in response to multiple insults, including glutamatergic excitotoxicity in hippocampal neurons, chemotherapy-induced cytotoxicity of dorsal root ganglion neurons, and retinal ganglion cells (RGCs) in rat retinal ischemia-reperfusion injury in vivo. Neuroprotection was dependent on VEGFR2 and MEK1/2 activation but not on p38 or phosphatidylinositol 3-kinase activation. Recombinant human VEGF-A165b is a neuroprotective agent that effectively protects both peripheral and central neurons in vivo and in vitro through VEGFR2, MEK1/2, and inhibition of caspase-3 induction. VEGF-A165b may be therapeutically useful for pathologies that involve neuronal damage, including hippocampal neurodegeneration, glaucoma diabetic retinopathy, and peripheral neuropathy. The endogenous nature of VEGF-A165b expression suggests that non-isoform-specific inhibition of VEGF-A (for antiangiogenic reasons) may be damaging to retinal and sensory neurons

    Can an Integrated Approach Reduce Child Vulnerability to Anaemia? Evidence from Three African Countries.

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    Addressing the complex, multi-factorial causes of childhood anaemia is best done through integrated packages of interventions. We hypothesized that due to reduced child vulnerability, a "buffering" of risk associated with known causes of anaemia would be observed among children living in areas benefiting from a community-based health and nutrition program intervention. Cross-sectional data on the nutrition and health status of children 24-59 mo (N = 2405) were obtained in 2000 and 2004 from program evaluation surveys in Ghana, Malawi and Tanzania. Linear regression models estimated the association between haemoglobin and immediate, underlying and basic causes of child anaemia and variation in this association between years. Lower haemoglobin levels were observed in children assessed in 2000 compared to 2004 (difference -3.30 g/L), children from Tanzania (-9.15 g/L) and Malawi (-2.96 g/L) compared to Ghana, and the youngest (24-35 mo) compared to oldest age group (48-59 mo; -5.43 g/L). Children who were stunted, malaria positive and recently ill also had lower haemoglobin, independent of age, sex and other underlying and basic causes of anaemia. Despite ongoing morbidity, risk of lower haemoglobin decreased for children with malaria and recent illness, suggesting decreased vulnerability to their anaemia-producing effects. Stunting remained an independent and unbuffered risk factor. Reducing chronic undernutrition is required in order to further reduce child vulnerability and ensure maximum impact of anaemia control programs. Buffering the impact of child morbidity on haemoglobin levels, including malaria, may be achieved in certain settings
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