11 research outputs found

    Conceptual design of an orbital debris collector

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    The current Lower Earth Orbit (LEO) environment has become overly crowded with space debris. An evaluation of types of debris is presented in order to determine which debris poses the greatest threat to operation in space, and would therefore provide a feasible target for removal. A target meeting these functional requirements was found in the Cosmos C-1B Rocket Body. These launchers are spent space transporters which constitute a very grave risk of collision and fragmentation in LEO. The motion and physical characteristics of these rocket bodies have determined the most feasible method of removal. The proposed Orbital Debris Collector (ODC) device is designed to attach to the Orbital Maneuvering Vehicle (OMV), which provides all propulsion, tracking, and power systems. The OMV/ODC combination, the Rocket Body Retrieval Vehicle (RBRV), will match orbits with the rocket body, use a spin table to match the rotational motion of the debris, capture it, despin it, and remove it from orbit by allowing it to fall into the Earth's atmosphere. A disposal analysis is presented to show how the debris will be deorbited into the Earth's atmosphere. The conceptual means of operation of a sample mission is described

    Flexible Plug Repair for Shuttle Wing Leading Edge

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    In response to the Columbia Accident Investigation Board report, a plug repair kit has been developed to enable astronauts to repair the space shuttle's wing leading edge (WLE) during orbit. The plug repair kit consists of several 17.78- cm-diameter carbon/silicon carbide (C/SiC) cover plates of various curvatures that can be attached to the refractory carbon-carbon WLE panels using a TZM refractory metal attach mechanism. The attach mechanism is inserted through the damage in the WLE panel and, as it is tightened, the cover plate flexes to conform to the curvature of the WLE panel within 0.050 mm. An astronaut installs the repair during an extravehicular activity (EVA). After installing the plug repair, edge gaps are checked and the perimeter of the repair is sealed using a proprietary material, developed to fill cracks and small holes in the WLE

    Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

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    In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

    Effective Practices and Recommendations for Drive-Through Clinic Points of Dispensing: A Systematic Review

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    Objective: Drive-through clinics (DTCs) are a novel type of point of dispensing where participants drive to a designated location and receive prophylaxis while remaining inside their vehicle. The objective of this review was to identify effective practices and recommendations for implementing DTCs for mass prophylaxis dispensing during emergency events. Methods: A systematic review was conducted for articles covering DTCs published between 1990 and 2019. Inclusion criteria were peer-reviewed, written in English, and addressed DTCs sufficiently. Effective practices and recommendations identified in the literature were presented by theme. Results: A total of 13 articles met inclusion criteria. The themes identified were (1) optimal DTC design and planning via decision support systems and decision support tools; (2) clinic layouts, locations, and design aspects; (3) staffing, training, and DTC communication; (4) throughput time; (5) community outreach methods; (6) DTC equipment; (7) infection prevention and personal protective equipment; and (8) adverse events prevention and traffic management. Conclusions: DTCs are an essential component of emergency preparedness and must be optimally designed and implemented to successfully dispense mass prophylaxis to a community within 48 hours. The effective practices and recommendations presented can be used for the development, implementation, and improvement of DTCs for their target populations

    Triggering of cardiovascular disease by infection type: The atherosclerosis risk in communities study (ARIC)

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    Introduction Acute infections are known triggers of cardiovascular disease (CVD) but how this association varies across infection types is unknown. We hypothesized while acute infections increase CVD risk, the strength of this association varies across infection types. Method Acute coronary heart disease (CHD) and ischemic stroke cases were identified in the Atherosclerosis Risk in Communities Study (ARIC). ICD-9 codes from Medicare claims were used to identify cellulitis, pneumonia, urinary tract infections (UTI), and bloodstream infections. A case-crossover design and conditional logistic regression were used to compare infection types among acute CHD and stroke cases 14, 30, 42, and 90 days before the event with two corresponding control periods (1 and 2 years prior). Results Of the 1312 acute CHD cases, 116 had a UTI, 102 had pneumonia, 43 had cellulitis, and 28 had a bloodstream infection 90 days before the CHD event. Pneumonia (OR = 25.53 (9.21,70.78)), UTI (OR = 3.32 (1.93, 5.71)), bloodstream infections (OR = 5.93 (2.07, 17.00)), and cellulitis (OR = 2.58 (1.09, 6.13)) were associated with higher acute CHD risk within 14 days of infection. Of the 727 ischemic stroke cases, 12 had cellulitis, 27 had pneumonia, 56 had a UTI, and 5 had a bloodstream infection within 90 days of the stroke. Pneumonia (OR = 5.59 (1.77, 17.67)) and UTI (OR = 3.16 (1.68, 5.94)) were associated with higher stroke risk within 14 days of infection. Conclusions Patients with pneumonia, UTI, or bloodstream infection appear to be at a 2.5 to 25.5 fold elevated CVD risk following infection. Preventive therapies during this high-risk period should be considered

    Trans-presentation of donor-derived interleukin 15 is necessary for the rapid onset of acute graft-versus-host disease but not for graft-versus-tumor activity

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    The “holy grail” of allogeneic stem cell transplantation is to preserve the graft-versus-tumor (GVT) effect while eliminating graft-versus-host disease (GVHD). Endogenous donor-derived interleukin 15 (IL-15) has been implicated in the pathogenesis of acute GVHD, yet the mechanism by which it impacts this lethal process remains unclear. Using the well-described and clinically relevant C57BL/6 → B6D2F1 murine model of acute GVHD, we demonstrate that in trans presentation of IL-15 by donor bone marrow–derived cells is required for the rapid onset of acute GVHD. Recipients of IL-15–/– C57BL/6 bone marrow cells show diminished type 1 polarization of T cells, yet there is no decrease in donor T-cell reconstitution. A molecular basis for these findings is provided with the observation that expression of T-bet, the master control gene for type 1 T-cell functions, is necessary for IL-15–mediated acute GVHD lethality. Finally, we demonstrate that in the absence of donor-derived IL-15, the GVT effect is maintained. These findings thus establish a mechanism by which endogenous donor-derived IL-15 impacts the pathobiology of acute GVHD and GVT activity
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