32 research outputs found

    B-cell anergy: from transgenic models to naturally occurring anergic B cells?

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    Anergy, a condition in which cells persist in the periphery but are unresponsive to antigen, is responsible for silencing many self-reactive B cells. Loss of anergy is known to contribute to the development of autoimmune diseases, including systemic lupus erythematosus and type 1 diabetes. Multiple transgenic mouse models have enabled the dissection of mechanisms that underlie anergy, and recently, anergic B cells have been identified in the periphery of wild-type mice. Heterogeneity of mechanistic concepts developed using model systems has complicated our understanding of anergy and its biological features. In this Review, we compare and contrast the salient features of anergic B cells with a view to developing unifying mechanistic hypotheses that explain their lifestyles

    Benefits of Realist Ontologies to Systems Engineering

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    Applied ontologies have been used more and more frequently to enhance systems engineering. In this paper, we argue that adopting principles of ontological realism can increase the benefits that ontologies have already been shown to provide to the systems engineering process. Moreover, adopting Basic Formal Ontology (BFO), an ISO standard for top-level ontologies from which more domain specific ontologies are constructed, can lead to benefits in four distinct areas of systems engineering: (1) interoperability, (2) standardization, (3) testing, and (4) data exploitation. Reaping these benefits in a model-based systems engineering (MBSE) context requires utilizing an ontology’s vocabulary when modeling systems and entities within those systems. If the chosen ontology abides by the principles of ontological realism, a semantic standard capable of uniting distinct domains, using BFO as a hub, can be leveraged to promote greater interoperability among systems. As interoperability and standardization increase, so does the ability to collect data during the testing and implementation of systems. These data can then be reasoned over by computational reasoners using the logical axioms within the ontology. This, in turn, generates new data that would have been impossible or too inefficient to generate without the aid of computational reasoners

    Ontology of plays for autonomous teaming and collaboration

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    We propose a domain-level ontology of plays for the facilitation of play-based collaborative autonomy among unmanned and manned-unmanned aircraft teams in the Army’s Unmanned Aircraft System (UAS) mission domain. We define a play as a type of plan that prescribes some pattern of intentional acts that are intended to reliably result in some goal in some competitive context, and which specifies one or more roles that are realized by those prescribed intentional acts. The ontology is well suited to be extended to other types of military and nonmilitary unmanned vehicle operations

    Examining the Association Between Rurality and Positive Childhood Experiences Among a National Sample

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    Purpose The present study examines the association between rurality and positive childhood experiences (PCEs) among children and adolescents across all 50 states and the District of Columbia. Recent work has quantified the prevalence of PCEs at the national level, but these studies have been based on public use data files, which lack rurality information for 19 states. Methods Data for this cross-sectional analysis were drawn from 2016 to 2018 National Survey of Children\u27s Health (NSCH), using the full data set with restricted geographic data (n = 63,000). Descriptive statistics and bivariate analyses were used to calculate proportions and unadjusted associations. Multivariable regression models were used to examine the association between residence and the PCEs that were significant in the bivariate analyses. Findings Rural children were more likely than urban children to be reported as having PCEs: volunteering in their community (aOR 1.29; 95% CI 1.18-1.42), having a guiding mentor (aOR 1.75; 95% CI 1.45-2.10), residing in a safe neighborhood (aOR 1.97; 95% CI 1.54-2.53), and residing in a supportive neighborhood (aOR 1.10; 95% CI 1.01-1.20) than urban children. Conclusions The assessment of rural-urban differences in PCEs using the full NSCH is a unique opportunity to quantify exposure to PCEs. Given the higher baseline rate of PCEs in rural than urban children, programs to increase opportunities for PCEs in urban communities are warranted. Future research should delve further into whether these PCEs translate to better mental health outcomes in rural children

    Maternal Cigarette Smoking during Pregnancy and Offspring Externalizing Behavioral Problems: A Propensity Score Matching Analysis

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    A body of empirical research has revealed that prenatal exposure to tobacco smoke is related to a host of negative outcomes, including reduced cognitive abilities, later-life health problems, and childhood behavioral problems. While these findings are often interpreted as evidence of the causal role that prenatal exposure to tobacco smoke has on human phenotypes, emerging evidence has suggested that the association between prenatal exposure to tobacco smoke and behavioral phenotypes may be spurious. The current analysis of data from the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B) revealed that the association between prenatal exposure to cigarette smoke and externalizing behavioral problems was fully accounted for by confounding factors. The implications that these findings have for policy and research are discussed

    The Determinants of Tornado Casualties and the Benefits of Tornado Shelters

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    Several recent powerful tornadoes have raised interest among the public and policymakers in tornado shelters. We estimate casualty functions (fatalities, injuries) based on factors like storm intensity, county population density, and time of day, using historical data from Oklahoma and then estimate expected tornado casualties for Oklahoma using historical tornado frequencies assuming no further market penetration of shelters. We then calculate the cost per life saved and injury prevented for shelters. The cost per life saved for shelters in permanent homes without discounting is around $30 million. Shelters will then provide cost effective protection for residents of mobile homes.
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