2,218 research outputs found

    Striatal neuroinflammation promotes parkinsonism in rats

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    The specific role of neuroinflammation in the pathogenesis of Parkinson's disease remains to be fully elucidated. By infusing lipopolysaccharide (LPS) into the striatum, we investigated the effect of neuroinflammation on the dopamine nigrostriatal pathway. Here, we report that LPS-induced neuroinflammation in the striatum causes progressive degeneration of the dopamine nigrostriatal system, which is accompanied by motor impairments resembling parkinsonism. Our results indicate that neurodegeneration is associated with defects in the mitochondrial respiratory chain related to extensive S-nitrosylation/nitration of mitochondrial proteins. Mitochondrial injury was prevented by treatment of L-N^6^-(l-iminoethyl)-lysine, an inducible nitric oxide synthase (iNOS) inhibitor, suggesting that iNOS-derived NO is responsible for mitochondrial dysfunction. Furthermore, the nigral dopamine neurons exhibited intracytoplasmic [alpha]-synuclein and ubiquitin accumulation. These results demonstrate that degeneration of nigral dopamine neurons by neuroinflammation is associated with mitochondrial malfunction induced by NO-mediated S-nitrosylation/nitration of mitochondrial proteins

    A Further Look at Potential Impact of Satlets on Design, Production, and Cost of Satellite Systems

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    For the past 50 years, the morphology for satellites has remained fundamentally unchanged despite evolutions in manufacturing, communications, and software occurring in other industries. Primary spacecraft support systems—power, attitude control, and others—are designed in the same way, whether in space telescopes, large communications satellites, interplanetary spacecraft, or Cubesats. This paradigm has been the status quo in spacecraft design and construction and has precluded any industry-wide, large-scale cost savings while maintaining performance. To change this trend and ensure performance and utility at low cost, that can scale, DARPA postulated the concept of a cellularized satellite, or “satlet,” as a satellite architectural unit. In this new morphology, each satlet would provide some fraction of the overall functions that, when aggregated via hardware and software, provide spacecraft space system with its complete required capabilities. The DARPA Phoenix program has developed this satlet morphology in Phase I and plans to validate and demonstrate it in a series of steps that exercise various applications and levels of configuration flexibility enabled by a satlet architecture. The first system experiment is planned to be conducted on orbit in 2015. This paper aims to take a deeper look at the potential impact of space systems with cellular based designs, and using historical data showcases how design, production and ultimately cost can form the foundation for next generation spacecraft opportunities. A first order analysis conducted in a previous paper indicated that U.S.-launched satellites alone could create a market demand for 2,000-8,000 satlets flown per year, while the overall annual world satellite market could create demand for 10,000-40,000 satlets. This paper explores the instantiation of a cellular morphology to design, production and development to further quantify the impact of this revolutionary space system capability


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    This study assessed agility ladder drills for the purpose of comparing kinetic characteristics of these drills to one another, and to sprinting and shuffling. Subjects (N=30) performed six agility ladder drills as well as sprinted and shuffled to the left and right over two large force platforms. A repeated measure ANOVA was used to assess horizontal and vertical ground reaction force (GRF) and the ratio of horizontal to vertical GRF, averaged from three steps for each drill. Significant main effects were found for all variables (p ≀ 0.001). Post-hoc analysis identified differences (p ≀ 0.05) between the agility drills as well as between the agility drills and the sprinting and shuffling. Results can be used to guide the progression of agility ladder drills based on known intensity and allow practitioners to prioritize drills that are most similar to sport-specific movements such as sprinting and shuffling

    Sustainability and resilience in midwifery: A discussion paper

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    Background midwifery workforce issues are of international concern. Sustainable midwifery practice, and how resilience is a required quality for midwives, have begun to be researched. How these concepts are helpful to midwifery continues to be debated. It is important that such debates are framed so they can be empowering for midwives. Care is required not to conceptually label matters concerning the midwifery workforce without judicious scrutiny and diligence. Aim the aim of this discussion paper is to explore the concepts of sustainability and resilience now being suggested in midwifery workforce literature. Whether sustainability and resilience are concepts useful in midwifery workforce development is questioned. Method using published primary midwifery research from United Kingdom and New Zealand the concepts of sustainability and resilience are compared, contrasted and explored. Findings there are obvious differences in models of midwifery care in the United Kingdom and New Zealand. Despite these differences, the concepts of resilience and sustainability emerge as overlapping themes from the respective studies’ findings. Comparison between studies provides evidence of what is crucial in sustaining healthy resilient midwifery practice. Four common themes have been identified that traverse the different models of care; Self-determination, ability to self-care, cultivation of relationships both professionally and with women/families, and a passion, joy and love for midwifery. Conclusions the impact that midwifery models of care may have on sustainable practice and nurturing healthy resilient behaviors remains uncertain. The notion of resilience in midwifery as the panacea to resolve current concerns may need rethinking. Resilience may be interpreted as expecting midwives ‘to toughen up’ in a workplace setting that is socially, economically and culturally challenging. Sustainability calls for examination of the reciprocity between environments of working and the individual midwife. The findings invite further examination of contextual influences that affect the wellbeing of midwives across different models of care

    Challenging homophobic bullying in schools: the politics of progress

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    In recent years homophobic bullying has received increased attention from NGOs, academics and government sources and concern about the issue crosses traditional moral and political divisions. This article examines this ‘progressive’ development and identifies the ‘conditions of possibility’ that have enabled the issue to become a harm that can be spoken of. In doing so it questions whether the readiness to speak about the issue represents the opposite to prohibitions on speech (such as the notorious Section 28) or whether it is based on more subtle forms of governance. It argues that homophobic bullying is heard through three key discourses (‘child abuse’, ‘the child victim’ and ‘the tragic gay’) and that, while enabling an acknowledgement of certain harms, they simultaneously silence other needs and experiences. It then moves to explore the aspirational and ‘liberatory’ political investments that underlie these seemingly ‘common-sense’ descriptive discourses and concludes with a critique of the quasi-criminal responses that the dominant political agenda of homophobic bullying gives rise to. The article draws on, and endeavours to develop a conversation between, critical engagements with the contemporary politics of both childhood and sexuality