179 research outputs found

    Thermionic reactor power system: Effects of radiation on integration with Manned Space Station

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    The application of a thermionic reactor power system to the modular space station is described. The nominal net power is 40 kWe, with the power system designed to be applicable over the power range from 25 to 60 kWe. The power system is designed to be launched by the space shuttle. Radiation protection is provided by LiH neutron shielding and W gamma shielding in a shaped 4 pion configuration, i.e., the reactor is shielded on all sides but not to equal extent. Isodose contours are presented for the region around the modular space station. Levels and spectral distribution of radiation are given for later evaluation of effects on space station experiments. Parametric data on the effects of separation distance on power system mass are presented

    Radioisotope thermionic power supply for spacecraft

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    Power supply design for unmanned electric propulsion missions to outer planets utilizes a store of curium-244 in compact array of capsules as energy source. Supply subassemblies are: heat source, converter equipment which supplies power, and safety equipment. System is designed for a 72,000 hour mission

    Thermionic reactors for electric propulsion - Parametric studies

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    Design parameters influence on size, mass, and reliability of thermionic reactors for electric propulsio

    Familiarity in Rural Life: Protocol for a Scoping Review and Concept Analysis

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    Background: Familiarity is a concept often used in literature but is not well defined or understood. As a key concept in rural nursing theory, the conceptual understanding of familiarity is currently incomplete. The findings from this scoping review will inform a concept analysis using Walker and Avant’s method and to identify and define the missing key components of familiarity. Objective: The objective of this scoping review is to examine and analyze what is known in the existing literature about the concept of familiarity. Methods: The Joanna Briggs Institute scoping review framework guided the identification of literature published from 2016 to 2022 on familiarity. Following the PRISMA-ScR (Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews) reporting standard, the familiarity scoping review is registered on Open Science Framework (registration digital object identifier: 10.17605/OSF.IO/ZB8VF). A total of 8 databases, including PubMed, CINAHL (Cumulative Index to Nursing and Allied Health Literature) Plus with full text, APA PsychInfo, Communication Source, EBSCO MegaFILE, Medline, Nursing & Allied Health Database, and ScienceDirect, will be searched for 22 search terms. Covidence software will be used to manage the scoping review with each citation independently reviewed by 2 research team members for eligibility. Eligibility will be determined using a 2-level process. Each title and abstract will be screened for eligibility; for citations deemed eligible, a full-text article review will be conducted. The scoping review is expected to locate a large body of literature, and eligibility criteria will be refined during the title and abstract screening process. In addition, reference list scanning will be performed to locate relevant literature. Results: Familiarity data will be collected beginning October 2021 with anticipated completion in March 2022. Dissemination of findings will occur through scholarly presentations and in rural-focused and nursing publications in 2022 or 2023. The findings from this review will further the understanding of familiarity and how it affects rural life and nursing practice. Conclusions: This review will support a full understanding and add clarity to the concept of familiarity as a component of rural life. These new insights will advance the understanding of how familiarity influences rural health care practice. The concept analysis will provide theoretical support for rural nursing theory and promote an understanding of the interrelationships of rural concepts

    Veterans in Crisis: Identifying and Reducing Suicide

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    The base of this Integrative Review is built on the foundation of information from research by Ramchand (2021), “Veterans are committing suicide at a rate twice the non-veteran.” (p.2) and “From 2005 to 2018 the suicide rate went from 20% to 32%” in the veteran population. (p.3). According to Ahmedani et al. (2019), “The majority of persons committing suicide (71.2%) had received health care in the 180 days prior to their death.” (p.6). This review analyzed and organized the findings to spotlight 4 common themes that lead to a better understanding of best practices. Eligibility criteria started with the PICOT question “In combat veterans, what role does untreated pain play in suicide rates?” The Preferred Reporting Items for Systematic Reviews and Meta-Analyses or PRISMA flow diagram was used to narrow the PubMed search results. The literature review focused directly on combat wounded veterans. The research links Post Traumatic Stress Disorder (PTSD) and chronic pain as a comorbidity that increases suicide risk. According to Chisholm-Burns et. al., (2019), “substantial evidence that pharmacists can make an impact through appropriate pain management.” (p.2) The goal of this review is to identify and reduce suicide in the veteran population

    Dietary soy and meat proteins induce distinct physiological and gene expression changes in rats

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    This study reports on a comprehensive comparison of the effects of soy and meat proteins given at the recommended level on physiological markers of metabolic syndrome and the hepatic transcriptome. Male rats were fed semi-synthetic diets for 1 wk that differed only regarding protein source, with casein serving as reference. Body weight gain and adipose tissue mass were significantly reduced by soy but not meat proteins. The insulin resistance index was improved by soy, and to a lesser extent by meat proteins. Liver triacylglycerol contents were reduced by both protein sources, which coincided with increased plasma triacylglycerol concentrations. Both soy and meat proteins changed plasma amino acid patterns. The expression of 1571 and 1369 genes were altered by soy and meat proteins respectively. Functional classification revealed that lipid, energy and amino acid metabolic pathways, as well as insulin signaling pathways were regulated differently by soy and meat proteins. Several transcriptional regulators, including NFE2L2, ATF4, Srebf1 and Rictor were identified as potential key upstream regulators. These results suggest that soy and meat proteins induce distinct physiological and gene expression responses in rats and provide novel evidence and suggestions for the health effects of different protein sources in human diets

    Same old song and dance: An exploratory study of portrayal of physical activity in television programmes aimed at young adolescents

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    Abstract Objective Exposure to health-related behaviours on television has been shown to influence smoking and drinking in young people, but little research has been conducted on the portrayal physical activity. The aim of the current project was to explore the portrayal of physical activity in television programmes aimed specifically at adolescent females. Content analysis of 120 episodes of four popular adolescent television programmes was performed. Information on the type and context of physical activity, motivating factors and characters involved was recorded. Results Physical activity was portrayed 122 times, for a duration of 1 h and 31 min (3.2% of total viewing time). Physical activity was mainly portrayed as part of an informal activity as part of a group activity. Over half (53.2%) of scenes portrayed activity been carried out by teenagers. The types of activities portrayed were mostly of vigorous intensity (76.2%), for recreational purposes (78.7%) such as dancing (54.1%) and running (11.5%), and motivated by enjoyment. This study highlights that physical activity is portrayed infrequently, and often with a skewed representation of type of activity. There may be an opportunity to influence physical activity in young adolescents through the positioning of positive images of an active lifestyle in the media

    Validity, Reliability, and Differential Item Functioning of English and French Versions of the 10-Item Connor-Davidson Resilience Scale in Systemic Sclerosis: A Scleroderma Patient-Centered Intervention Network Cohort Study

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    Objective Some individuals with systemic sclerosis (SSc) report positive mental health, despite severe disease manifestations, which may be associated with resilience, but no resilience measure has been validated in SSc. This study was undertaken to assess the validity, reliability, and differential item functioning (DIF) between English- and French-language versions of the 10-item Connor-Davidson Resilience Scale (CD-RISC-10) in SSc. Methods Eligible participants were enrolled in the Scleroderma Patient-centered Intervention Network Cohort and completed the CD-RISC-10 between August 2022 and January 2023. We used confirmatory factor analysis (CFA) to evaluate the CD-RISC-10 factor structure and conducted DIF analysis across languages with Multiple Indicators Multiple Causes models. We tested convergent validity with another measure of resilience and measures of self-esteem and depression and anxiety symptoms. We assessed internal consistency and test–retest reliability using Cronbach\u27s alpha and intraclass correlation coefficient (ICC). Results A total of 962 participants were included in this analysis. CFA supported a single-factor structure (Tucker–Lewis index = 0.99, comparative fit index = 0.99, root mean square error of approximation = 0.08 [90% confidence interval (90% CI) 0.07, 0.09]). We found no meaningful DIF. Internal consistency was high (α = 0.93 [95% CI 0.92, 0.94]), and we found that correlations with other measures of psychological functioning were moderate to large (|r| = 0.57–0.78) and confirmed study hypotheses. The scale showed good 1–2-week test–retest reliability (ICC 0.80 [95% CI 0.75, 0.85]) in a subsample of 230 participants. Conclusion The CD-RISC-10 is a valid and reliable measure of resilience in SSc, with score comparability across English and French versions
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