88 research outputs found

    Herding with Heterogeneous Ability: An Application to Organ Transplantation

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    There are many economic environments in which an object is offered sequentially to prospective buyers. It is often observed that once the object for sale is turned down by one or more agents, those that follow do the same. One explanation that has been proposed for this phenomenon is that agents making choices further down the line rationally ignore their own assessment of the object’s quality and herd behind their predecessors. Our research adds a new dimension to the canonical herding model by allowing agents to di er in their ability to assess the quality of the offered object. We develop novel tests of herding based on this ability heterogeneity and also examine its efficiency consequences, applied to organ transplantation in the U.K. We nd that herding is common but that the information lost due to herding does not substantially increase false discards of good organs or false acceptances of bad organs. Our counter-factual analysis indicates that this is due (in part) to the high degree of heterogeneity in ability across transplant centers. In other settings, such as the U.S., where organ transplantation is organized very differently and the ability distribution will not be the same, the inefficiencies due to herding might well be substantial

    Characteristics of gay, bisexual and other men who have sex with men with multiple diagnoses of infectious syphilis in British Columbia, Canada, 2005-2014

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    Background: Infectious syphilis has increased substantially over the past decade. Targeting limited public health resources toward subpopulations with multiple reinfections may have a large impact in reducing onward transmission within a community. Methods: A chart review was conducted for individuals with 4 or more infectious syphilis diagnoses between 2005 and 2014 (the top 1% of all syphilis diagnoses in British Columbia, Canada). We characterized the sociodemographics, partner notification outcomes and social network. Results: Between 2005 and 2014, there were 30 individuals with 4 or more syphilis diagnoses, accounting for 139 diagnoses. All were men who have sex with men and 29 (96%) were human immunodeficiency virus–positive. Of the 139 diagnoses, 65% occurred in the early latent stage of infection, 22% in the secondary stage, and 14% in the primary stage. The median number of sexual partners per diagnosis was 5 (range, 1–50). Among the 838 partners reported, 79% were notifiable, 53% were notified, and 23% were reported to be tested or treated. Sexual network mapping showed that almost half of the members of this group could be linked to one another either directly or indirectly via partners over 10 years. Social network mapping demonstrated high connectivity, with 4 venues associated with almost two thirds of the study population. Conclusions: The connectivity and recurrent diagnoses in this study population suggest potential benefits of targeted interventions to individuals with multiple diagnoses and their partners. Our study highlights the need for enhanced care, increased syphilis testing frequency, and exploring alternative preventative methods among individuals with syphilis rediagnoses to reduce syphilis incidence

    Influence of microRNAs from Semen on Bovine Fertility

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    The objective of this study was to compare the miRNAs within sperm cells of bulls considered to have high and low fertility

    TDP-43-Mediated Neuron Loss In Vivo Requires RNA-Binding Activity

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    Alteration and/or mutations of the ribonucleoprotein TDP-43 have been firmly linked to human neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). The relative impacts of TDP-43 alteration, mutation, or inherent protein function on neural integrity, however, remain less clear—a situation confounded by conflicting reports based on transient and/or random-insertion transgenic expression. We therefore performed a stringent comparative investigation of impacts of these TDP-43 modifications on neural integrity in vivo. To achieve this, we systematically screened ALS/FTLD-associated and synthetic TDP-43 isoforms via same-site gene insertion and neural expression in Drosophila; followed by transposon-based motor neuron-specific transgenesis in a chick vertebrate system. Using this bi-systemic approach we uncovered a requirement of inherent TDP-43 RNA-binding function—but not ALS/FTLD-linked mutation, mislocalization, or truncation—for TDP-43-mediated neurotoxicity in vivo

    A central support system can facilitate implementation and sustainability of a Classroom-based Undergraduate Research Experience (CURE) in Genomics

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    In their 2012 report, the President\u27s Council of Advisors on Science and Technology advocated replacing standard science laboratory courses with discovery-based research courses -a challenging proposition that presents practical and pedagogical difficulties. In this paper, we describe our collective experiences working with the Genomics Education Partnership, a nationwide faculty consortium that aims to provide undergraduates with a research experience in genomics through a scheduled course (a classroom-based undergraduate research experience, or CURE). We examine the common barriers encountered in implementing a CURE, program elements of most value to faculty, ways in which a shared core support system can help, and the incentives for and rewards of establishing a CURE on our diverse campuses. While some of the barriers and rewards are specific to a research project utilizing a genomics approach, other lessons learned should be broadly applicable. We find that a central system that supports a shared investigation can mitigate some shortfalls in campus infrastructure (such as time for new curriculum development, availability of IT services) and provides collegial support for change. Our findings should be useful for designing similar supportive programs to facilitate change in the way we teach science for undergraduates
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