748 research outputs found

    Requirements and applications for robotic servicing of military space systems

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    The utility of on-orbit servicing of spacecraft has been demonstrated by NASA several times using shuttle-based astronaut EVA. There has been interest in utilizing on-orbit servicing for military space systems as well. This interest has been driven by the increasing reliance of all branches of the military upon space-based assets, the growing numbers, complexity, and cost of those assets, and a desire to normalize support policies for space-based operations. Many military satellites are placed in orbits which are unduly hostile for astronaut operations and/or cannot be reached by the shuttle. In addition, some of the projected tasks may involve hazardous operations. This has led to a focus on robotic systems, instead of astronauts, for the basis of projected servicing systems. This paper describes studies and activities which will hopefully lead to on-orbit servicing being one of the tools available to military space systems designers and operators. The utility of various forms of servicing has been evaluated for present and projected systems, critical technologies have been identified, and strategies for the development and insertion of this technology into operational systems have been developed. Many of the projected plans have been adversely affected by budgetary restrictions and evolving architectures, but the fundamental benefits and requirements are well understood. A method of introducing servicing capabilities in a manner which has a low impact on the system designer and does not require the prior development of an expensive infrastructure is discussed. This can potentially lead to an evolutionary implementation of the full technology

    Trudy\u27s Triumph: A Narrative Life History of an Adolescent Survivor of Abusive Head Trauma

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    The purpose of this narrative study was to describe the life history of an adolescent survivor of an abusive head trauma in the Southeastern United States. Abusive head trauma is a form of inflicted brain injury, often occurring because of violence in the form of shaking or impact to the head of an infant under the age of two years old (Chevignard & Lind, 2014). Life history is defined as a first-hand account to convey understanding of a life. The primary participant was a 19-year-old, Caucasian female survivor of an abusive head trauma that occurred when she was five months old. Secondary participants include the survivor’s family members, a family friend, a special education teacher and a church youth leader. The theoretical framework of this study was based on Bronfenbrenner’s (1979) ecology of human development, Ungar’s (2012) theory of social-ecological resilience, and Bandura’s (1986) social cognitive theory. The central research question was: What are the lived experiences of an adolescent survivor of an abusive head trauma in the Southeastern United States? Data was collected through interviews, observations, documents, artifacts, video journal, and prolonged engagement with the survivor and her family. Data was analyzed to describe the story and place it in a chronology to present narration focusing on processes, theories, and unique general features of the primary participant’s life. Findings indicated that the primary participant faced neurological, cognitive, behavioral, academic and social challenges, while her resilience mechanisms included a large support network, adaptive behaviors, faith and perseverance. This study makes an original, empirical contribution as the sole account of the life history of an adolescent survivor of an abusive head trauma

    RICE Limits on the Diffuse Ultra-High Energy Neutrino Flux

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    We present new limits on ultra-high energy neutrino fluxes above 100 PeV based on data collected by the Radio Ice Cherenkov Experiment (RICE) at the South Pole from 1999-2005. We discuss estimation of backgrounds, calibration and data analysis algorithms (both on-line and off-line), procedures used for the dedicated neutrino search, and refinements in our Monte Carlo (MC) simulation, including recent in situ measurements of the complex ice dielectric constant. An enlarged data set and a more detailed study of hadronic showers results in a sensitivity improvement of more than one order of magnitude compared to our previously published results. Examination of the full RICE data set yields zero acceptable neutrino candidates, resulting in 95% confidence-level model dependent limits on the flux (E_\nu)^2(d\phi/dE_\nu)<10^{-6} GeV/(cm^2s~sr}) in the energy range 10^{17}< E_\nu< 10^{20} eV. The new RICE results rule out the most intense flux model projections at 95% confidence level.Comment: Submitted to Astropart. Phy

    Allergen immunotherapy on the way to product-based evaluation - a WAO statement

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    Allergen immunotherapy (AIT) is widely used in clinical practice for patients with moderate to severe allergic rhinitis due to inhalant allergens and may be delivered via subcutaneous (SCIT) and sublingual routes (SLIT). However, the quality of evidence for individual AIT products is very heterogeneous, and extensions of overall conclusions ("class effects") on the efficacy and disease-modifying effects to all AIT products are unjustified. In contrast, each product needs to be evaluated individually, based on available study results, to justify efficacy and specific claims on sustained and disease modifying effects per allergen and targeted patient group (children vs. adults, allergic rhinitis vs. asthma). WAO intends to support the current development to evidence-based AIT, which ultimately will lead to a more efficacious treatment of allergic patients and the appropriate recognition of AIT

    A mutation in SFTPA1 and pulmonary fibrosis

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    Idiopathic pulmonary fibrosis (IPF) is a fatal disease characterized by scattered fibrotic lesions in the lungs. The pathogenesis and genetic basis of IPF remain poorly understood. Here, we show that a homozygous missense mutation in SFTPA1 caused IPF in a consanguineous Japanese family. The mutation in SFTPA1 disturbed the secretion of SFTPA1 protein. Sftpa1 knock-in (Sftpa1-KI) mice that harbored the same mutation as patients spontaneously developed pulmonary fibrosis that was accelerated by influenza virus infection. Sftpa1-KI mice showed increased necroptosis of alveolar epithelial type II (AEII) cells with phosphorylation of IRE1α leading to JNK-mediated up-regulation of Ripk3. The inhibition of JNK ameliorated pulmonary fibrosis in Sftpa1-KI mice, and overexpression of Ripk3 in Sftpa1-KI mice treated with a JNK inhibitor worsened pulmonary fibrosis. These findings provide new insight into the mechanisms of IPF in which a mutation in SFTPA1 promotes necroptosis of AEII cells through JNK-mediated up-regulation of Ripk3, highlighting the necroptosis pathway as a therapeutic target for IPF

    Surfactant Protein-A Suppresses Eosinophil-Mediated Killing of Mycoplasma pneumoniae in Allergic Lungs

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    Surfactant protein-A (SP-A) has well-established functions in reducing bacterial and viral infections but its role in chronic lung diseases such as asthma is unclear. Mycoplasma pneumoniae (Mp) frequently colonizes the airways of chronic asthmatics and is thought to contribute to exacerbations of asthma. Our lab has previously reported that during Mp infection of non-allergic airways, SP-A aides in maintaining airway homeostasis by inhibiting an overzealous TNF-alpha mediated response and, in allergic mice, SP-A regulates eosinophilic infiltration and inflammation of the airway. In the current study, we used an in vivo model with wild type (WT) and SP-A−/− allergic mice challenged with the model antigen ovalbumin (Ova) that were concurrently infected with Mp (Ova+Mp) to test the hypothesis that SP-A ameliorates Mp-induced stimulation of eosinophils. Thus, SP-A could protect allergic airways from injury due to release of eosinophil inflammatory products. SP-A deficient mice exhibit significant increases in inflammatory cells, mucus production and lung damage during concurrent allergic airway disease and infection (Ova+Mp) as compared to the WT mice of the same treatment group. In contrast, SP-A deficient mice have significantly decreased Mp burden compared to WT mice. The eosinophil specific factor, eosinophil peroxidase (EPO), which has been implicated in pathogen killing and also in epithelial dysfunction due to oxidative damage of resident lung proteins, is enhanced in samples from allergic/infected SP-A−/− mice as compared to WT mice. In vitro experiments using purified eosinophils and human SP-A suggest that SP-A limits the release of EPO from Mp-stimulated eosinophils thereby reducing their killing capacity. These findings are the first to demonstrate that although SP-A interferes with eosinophil-mediated biologic clearance of Mp by mediating the interaction of Mp with eosinophils, SP-A simultaneously benefits the airway by limiting inflammation and damage

    ONZIN deficiency attenuates contact hypersensitivity responses in mice

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    ONZIN is abundantly expressed in immune cells of both the myeloid and lymphoid lineage. Expression by lymphoid cells has been reported to further increase after cutaneous exposure of mice to antigens and haptens capable of inducing contact hypersensitivity, suggesting that ONZIN plays a critical role in this response. Here, we report that indeed ONZIN-deficient mice develop attenuated CHS to a number of different haptens. Dampened CHS responses correlated with a significant reduction in pro-inflammatory IL-6 at the challenge site in ONZIN-deficient animals compared to wild type controls. Together the study of these animals indicates that loss of ONZIN impacts the effector phase of the CHS response through the regulation of pro-inflammatory factors

    Possibilities and Pitfalls of Social Media for Translational Medicine

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    We live in an age where the sharing of scientific findings and ideas is no longer confined to people with access to academic libraries or scientific journals. Social media have permitted for knowledge and ideas to be shared with an unprecedented speed and magnitude. This has made it possible for research findings to have a greater impact and to be rapidly implemented in society. However, the spread of unfiltered, unreferenced, and non-peer-reviewed articles through social media comes with dangers as well. In this perspective article, we aim to address both the possibilities and pitfalls of social media for translational medicine. We describe how social media can be used for patient engagement, publicity, transparency, sharing of knowledge, and implementing findings in society. Moreover, we warn about the potential pitfalls of social media, which can cause research to be misinterpreted and false beliefs to be spread. We conclude by giving advice on how social media can be harnessed to combat the pitfalls and provide a new avenue for community engagement in translational medicine
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