3,849 research outputs found

    The Effect of Rewards and Sanctions in Provision of Public Goods

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    A growing number of field and experimental studies focus on the institutional arrangements by which individuals are able to solve collective action problems. Important in this research is the role of reciprocity and institutions that facilitate cooperation via opportunities for monitoring, sanctioning, and rewarding others. Sanctions represent a cost to both the participant imposing the sanction and the individual receiving the sanction. Rewards represent a zero sum transfer from participants giving to those receiving rewards. We contrast reward and sanction institutions in regard to their impact on cooperation and efficiency in the context of a public goods experiment.

    Hierarchical strategies for efficient fault recovery on the reconfigurable PAnDA device

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    A novel hierarchical fault-tolerance methodology for reconfigurable devices is presented. A bespoke multi-reconfigurable FPGA architecture, the programmable analogue and digital array (PAnDA), is introduced allowing fine-grained reconfiguration beyond any other FPGA architecture currently in existence. Fault blind circuit repair strategies, which require no specific information of the nature or location of faults, are developed, exploiting architectural features of PAnDA. Two fault recovery techniques, stochastic and deterministic strategies, are proposed and results of each, as well as a comparison of the two, are presented. Both approaches are based on creating algorithms performing fine-grained hierarchical partial reconfiguration on faulty circuits in order to repair them. While the stochastic approach provides insights into feasibility of the method, the deterministic approach aims to generate optimal repair strategies for generic faults induced into a specific circuit. It is shown that both techniques successfully repair the benchmark circuits used after random faults are induced in random circuit locations, and the deterministic strategies are shown to operate efficiently and effectively after optimisation for a specific use case. The methods are shown to be generally applicable to any circuit on PAnDA, and to be straightforwardly customisable for any FPGA fabric providing some regularity and symmetry in its structure

    Aspidoscelis laredoensis and A. gularis hybridization.

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    13 pages : illustrations (some color) ; 26 cm.Karyotypes and allozyme data for 32 genetic loci overwhelmingly support the conclusion that Aspidoscelis laredoensis is a diploid all-female species that had a hybrid origin between A. gularis x A. sexlineatus. Comparisons of allozymes in individuals representing three mother-to-daughter generations raised in the laboratory suggest that they reproduce by parthenogenetic cloning. In addition to two previously described morphotypes (pattern classes A and B) that occur in southern Texas, we report the existence of three all-female clonal lineages based on allozymes. Individuals of at least one of these lineages occasionally hybridize in nature with males of A. gularis, producing viable and healthy triploid offspring that can grow to adulthood, one of which herself produced an offspring in the laboratory and could have represented a new, clonal triploid species. The possibility exists that cloned offspring of triploid hybrids are present in South Texas and/or northern Mexico, awaiting discovery. These would represent a new species that would appear to be very similar to A. laredoensis

    Reduced efficacy of praziquantel against Schistosoma mansoni associated with multiple-rounds of mass drug administration

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    The efficacy of praziquantel against Schistosoma mansoni was significantly lower in Ugandan schools that had received more prior rounds of mass drug administration, as determined by fitting a statistical model to parasite egg counts before and after treatment

    Meristic variability in whiptail lizards

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    24 p. : ill. ; 26 cm.Is it correct, as is often assumed, that the clonal form of inheritance in parthenogenetic lizards results in less variability than occurs with genetic recombination in their sexually reproducing (gonochoristic) relatives? We tested this hypothesis by comparing morphological variability in samples of parthenogenetic Aspidoscelis tesselata and several gonochoristic species of whiptail lizards. To control for environmental factors that might differentially affect embryonic development of morphological characters, we compared samples obtained from the same or geographically adjacent localities. In addition, we compared apparently "uniclonal" and multiclonal samples from each of two color-pattern classes (C and E) of A. tesselata. For univariate meristic characters, parthenogenetic A. tesselata matched the variability of a sympatric gonochoristic species in 11 of 20 comparisons, had lower variability in six comparisons, and was more variable in three. For multivariate characters derived from principal components analyses (PCA), the relative meristic variability of samples of A. tesselata could not be predicted by its reproductive mode, color-pattern class, apparent "uniclonal" or multiclonal state, or geographic location. In addition, we compared A. tesselata, A. sexlineata, A. marmorata, and A. gularis septemvittata in a single PCA, with the latter two species representing the two ancestral taxa from which A. tesselata was derived through hybridization. Once again, relative variability of A. tesselata was not always predictable based on its reproductive mode. It had greater variability than A. sexlineata, equivalent variability with A. gularis septemvittata, and less variability than A. marmorata

    The endoribonuclease YbeY is linked to proper cellular morphology and virulence in 2 Brucella abortus

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    The endoribonuclease YbeY is one of the most well conserved proteins across the kingdoms of life. In the present study, we demonstrate that YbeY in Brucella abortus is linked to a variety of important activities, including proper cellular morphology, mRNA transcript levels, and virulence. Deletion of ybeY in B. abortus led to a small colony phenotype when the bacteria were grown on agar medium, as well as significant aberrations in the morphology of the bacterial cell as evidenced by electron microscopy. Additionally, compared to the parental strain, the ΔybeY strain was significantly attenuated in both macrophage and mouse models of infection. The ΔybeY strain also showed increased sensitivities to several in vitro applied stressors, including bile acid, hydrogen peroxide, SDS, and paraquat. Transcriptomic analysis revealed that a multitude of mRNA transcripts are dysregulated in the ΔybeY strain, and many of the identified mRNAs encode proteins involved in metabolism, nutrient transport, transcriptional regulation, and flagellum synthesis. We subsequently constructed gene deletion strains of the most highly dysregulated systems, and several of the YbeY-linked gene deletion strains exhibited defects in the ability of the bacteria to survive and replicate in primary murine macrophages. Altogether, these data establish a clear role for YbeY in the biology and virulence of Brucella, and moreover, this work further illuminates the highly varied roles of this widely conserved endoribonuclease in bacteria. Importance Brucella spp. are highly efficient bacterial pathogens of animals and humans, causing significant morbidity and economic loss worldwide, and relapse of disease often occurs following antibiotic treatment of human brucellosis. As such, novel therapeutic strategies to combat Brucella infections are needed. Ribonucleases in the brucellae are understudied, and these enzymes represent elements that may be potential targets for future treatment approaches. The present work demonstrates the importance of the endoribonuclease YbeY for cellular morphology, efficient control of mRNA levels, and virulence in B. abortus. Overall, this study advances our understanding of the critical roles of YbeY in the pathogenesis of the intracellular brucellae and expands our understanding of this highly conserved ribonuclease.National Institute of General Medical Sciences (U.S.) (Grant GM31030

    Nurses\u27 Alumnae Association Bulletin - Volume 6 Number 10

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    Financial Report Calendar of Events Attention, Class of 1945! Miss Shafer Retires Review of the Alumnae Association Meetings Institutional Staff Nurses\u27 Section Report of Staff Activites - 1948-1949 The Staff Stockings! Stockings! Stockings! Pop-Up Toaster It\u27s Not Too Soon Any White Elephants? Private Duty Section The Jefferson Hospital Private Duty Nurses\u27 Register Report for Barton Memorial Hospital Progress of the Orthopedic Department Just Under the Date Line Pediatrics at Jefferson Controlled Respiration in Anesthesia Anesthesia Progress Physical Advances at Jefferson During the Past Year The White Haven Division The Clara Melville Scholarship Fund The Relief Fund The Busy Year for the Nurses\u27 Home Committee of the Women\u27s Board The Gray Ladies Memories Lost Miscellaneous Items Medical College News Marriages Births Deaths Condolences Prizes District No. 1 Dues Help! Help! Help! Jap Prison School Spurs Nurse to Win University Degree Twenty Ways to Kill an Organization The Bulletin Committee Attention, Alumnae New Addresse

    The Antarctic Submillimeter Telescope and Remote Observatory (AST/RO)

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    AST/RO, a 1.7 m diameter telescope for astronomy and aeronomy studies at wavelengths between 200 and 2000 microns, was installed at the South Pole during the 1994-1995 Austral summer. The telescope operates continuously through the Austral winter, and is being used primarily for spectroscopic studies of neutral atomic carbon and carbon monoxide in the interstellar medium of the Milky Way and the Magellanic Clouds. The South Pole environment is unique among observatory sites for unusually low wind speeds, low absolute humidity, and the consistent clarity of the submillimeter sky. Four heterodyne receivers, an array receiver, three acousto-optical spectrometers, and an array spectrometer are installed. A Fabry-Perot spectrometer using a bolometric array and a Terahertz receiver are in development. Telescope pointing, focus, and calibration methods as well as the unique working environment and logistical requirements of the South Pole are described.Comment: 57 pages, 15 figures. Submitted to PAS

    Systematic review of studies generating individual participant data on the efficacy of drugs for treating soil-transmitted helminthiases and the case for data-sharing

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    Preventive chemotherapy and transmission control (PCT) by mass drug administration is the cornerstone of the World Health Organization (WHO)’s policy to control soil-transmitted helminthiases (STHs) caused by Ascaris lumbricoides (roundworm), Trichuris trichiura (whipworm) and hookworm species (Necator americanus and Ancylostama duodenale) which affect over 1 billion people globally. Despite consensus that drug efficacies should be monitored for signs of decline that could jeopardise the effectiveness of PCT, systematic monitoring and evaluation is seldom implemented. Drug trials mostly report aggregate efficacies in groups of participants, but heterogeneities in design complicate classical meta-analyses of these data. Individual participant data (IPD) permit more detailed analysis of drug efficacies, offering increased sensitivity to identify atypical responses potentially caused by emerging drug resistance
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