193 research outputs found

    Relationship between perceived and actual quality of data checking

    Full text link
    Data quality is critical to reaching correct research conclusions. Researchers attempt to ensure that they have accurate data by checking the data after it has been entered. Previous research has demonstrated that some methods of data checking are better than others, but not all researchers use the best methods. Perhaps researchers continue to use less optimal data checking methods because they mistakenly believe that they are highly accurate. The purpose of this study was to examine the relationship between perceived data quality and actual data quality. A total of 29 participants completed this study. Participants checked that letters and numbers had been entered correctly into the computer using one of three randomly assigned data checking methods. Afterwards, they rated the quality of their data checking method. The sample correlations between perceived and actual data quality were small to moderate and confidence intervals for the population correlations did not include high values. We conclude that the relationship between actual and perceived data quality is not high

    HERC 1 Ubiquitin Ligase Mutation Affects Neocortical, CA3 Hippocampal and Spinal Cord Projection Neurons: An Ultrastructural Study

    Get PDF
    The spontaneous mutation tambaleante is caused by the Gly483Glu substitution in the highly conserved N terminal RCC1-like domain of the HERC1 protein, which leads to the increase of mutated protein levels responsible for cerebellar Purkinje cell death by autophagy. Until now, Purkinje cells have been the only central nervous neurons reported as being targeted by the mutation, and their degeneration elicits an ataxic syndrome in adult mutant mice.MINECO JCI-2011-08888DGICYT Spanish Government BFU2011-27207Junta de Andalucía CTS-2257Ministerio de Ciencia e Innovación BFU2011-22498VPPI-US University of Sevill

    Unusual chemical composition of a Mexican Propolis collected in Yucatan

    Get PDF
    Introduction: Propolis, or bee glue, is a natural resinous hive product collected by honeybees from buds and exudates of various trees and plants. Mixed with beewax and salivary enzymes, it is employed to fill cracks and embalm dead invaders in the hive. Several studies about mexican propolis have revealed chemical profiles where cinnamic and phenylpropanoic acid derivatives as well as flavonoids dominated, whereas these extracts exhibited cytotoxic and/or antifungal activities. Research methods: An ethanolic extract of a batch of mexican propolis, collected in the state of Quintana Roo, Mexico, was first analysed by High Performance Liquid Chromatography coupled with Diode Array Detector (HPLC/DAD) but no major components could be detected. Its antioxidant activity was evaluated by 1,1-diPhenyl-2-PicrylHydrazyl (DPPH) assay as well, and its antibacterial (against 21 Gram-positive and Gram-negative strains including Staphyloccocus aureus) and antifungal (against Candida albicans and Aspergillus fumigatus) properties were evaluated through microdilution assays. Then, this extract was fractionated by Flash chromatography. Three of the fractions, containing the major constituents, were analysed by Gas Chromatography coupled with Mass Spectrometry (GC/MS). Results and discussion: This Mexican propolis did not show any antioxidant neither antibacterial nor antifungal activity. The main constituents of this Mexican propolis were identified as triterpenes (amyrenone, amyrin and amyrin-3-acetate) and sterols (fucosterol and sistosterol). This unusual composition associated with a Mexican propolis would thus explain the lack of biological activities. Further investigations will be conducted in order to link this chemical composition with the propolis plant sources

    McNair Research Journal - Summer 2015

    Full text link
    Journal articles based on research conducted by undergraduate students in the McNair Scholars Program Table of Contents Biography of Dr. Ronald E. McNair Statements: Dr. Neal J. Smatresk, UNLV President Dr. Juanita P. Fain, Vice President of Student Affairs Dr. William W. Sullivan, Associate Vice President for Retention and Outreach Mr. Keith Rogers, Deputy Executive Director of the Center for Academic Enrichment and Outreach McNair Scholars Institute Staf

    Female labour market outcomes and the impact of maternity leave policies

    Get PDF
    ABSTRACT: This paper shows how family policies aimed at reconciling the pressures of family and work generate substantial variation in labour market outcomes across developed countries. We use a life-cycle model of female labour supply and savings behaviour, calibrated to the US economy, to assess the effect of introducing to the US a maternity leave policy similar to Scandinavian-type policies. We focus on the impact on gender differences in participation and in wages. We distinguish between the effect of the job protection offered by maternity leave and the effect of income replacement. Job protection leads to substantial increases in participation of mothers with children under 6, but with little long term effects. The effects on wages are minimal, with negative selection effects offsetting the reduced human capital depreciation. Income replacement has a limited impact on participation or wages.Virginia Sánchez-Marcos thanks the Spanish Ministry of Science and Technology for Grant ECO2009-09614 and RecerCaixa for financial support

    Financial Structure and Economic Welfare: Applied General Equilibrium Development Economics

    Get PDF
    This review provides a common framework for researchers thinking about the next generation of micro-founded macro models of growth, inequality, and financial deepening, as well as direction for policy makers targeting microfinance programs to alleviate poverty. Topics include treatment of financial structure general equilibrium models: testing for as-if-complete markets or other financial underpinnings; examining dual-sector models with both a perfectly intermediated sector and a sector in financial autarky, as well as a second generation of these models that embeds information problems and other obstacles to trade; designing surveys to capture measures of income, investment/savings, and flow of funds; and aggregating individuals and households to the level of network, village, or national economy. The review concludes with new directions that overcome conceptual and computational limitations.National Science Foundation (U.S.)National Institutes of Health (U.S.)Templeton FoundationBill & Melinda Gates Foundatio
    corecore