211 research outputs found

    Apollo to Artemis: Mining 50-Year Old Records to Inform Future Human Lunar Landing Systems

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    Under the Artemis lunar exploration program, NASA is committed to landing American astronauts on the moon by 2024. While NASAs new Space Launch System rocket and Orion capsule will carry astronauts from Earth to the Gateway, the human lunar landing system has not yet been fully defined. As in the Apollo program, there are concerns for vehicle weight and internal volume such that seats may not be desirable, and standing during lunar descent and ascent may be a preferred engineering solution. With such a design, astronauts will experience +GZ (head-to-foot) accelerations during capsule accelerations, and it is unclear whether spaceflight deconditioned astronauts can tolerate these. Apollo astronauts stood during lunar descent and ascent, and the data contained in the early program records for those missions represent a unique resource that may provide insights to the cardiovascular stress associated with this human landing system design

    Two Years Retrospective Study of Metalceramic Crowns with Nickelchromium Alloy

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    Crown and bridge stability in the human mouth is not easy to evaluate. The structure and quality of crown materials are directly connected with the hardness and composition of the surface. The aim of the study was to evaluate the long-term stability of 52 crowns (19 patients) made from ceramic material (Vita Omega, Vita) and nickelchromium ceramic bonding metal alloy (Wiron, Bego) in clinical practice. In accordance with the US Public Health Service System changes in occlusal anatomy, occlusal relief, marginal adaptation, material break age, changes of shape and color, were checked. Another objective of the study was to observe the two year clinical progress of attrition of crowns. Replica casts (Epoxy-die (Ivoclar) were prepared. A scanning electron microscope (JEOL ; JMS-5500 LV (JEOL) and standard model (Ivoclar - Williams) were used to evaluate the quality of restoration. No changes in the shape and color were found, postop sensitivity was present in 1.9 %, and caries presence has been detected in 1.9 %. After two years the labial or buccal coronal margin was recorded as being at the level ofthe adjacent gingiva for 34.6 % of the 52 crowns placed and above the gingival margin for 65.4% of the crowns. Marginal adaptation was rated as contiguous with the existing anatomic form in 71.2 %. Gingival health varied from 0 to 2 CPITN index.Abrasion in fissures was visible in the scanning electron microscope. The cusps were well formed. Two fractures of the ceramic layer were observed. A significant increase in the position of the gingival margins was found, and varied from 45.0 ÎŒm to 108.3 ÎŒm vestibular 89.1 (SE12.1) to 63 ÎŒm oral (SE 7.0)

    A Systemically-Administered Small Molecule Antagonist of CCR9 Acts as a Tissue-Selective Inhibitor of Lymphocyte Trafficking

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    A goal for developers of immunomodulatory drugs has long been a systemically administered small molecule that can selectively inhibit inflammation in specific tissues. The chemokine receptor CCR9 is an attractive target for this approach, as entry of T cells into the small intestine from blood requires interaction between CCR9 and its ligand CCL25. We have tested the ability of a small molecule CCR9 antagonist, CCX8037, to inhibit antigen-mediated T cell accumulation in the intestine. This compound prevented accumulation of gut-imprinted antigen-specific CD8 T cells within epithelium of the small intestine. Interestingly, the antagonist did not affect the robust generation of gut-imprinted CD8 T cells within mesenteric lymph nodes. To distinguish “gut-selective” from “general” T cell inhibition, we tested the drug’s ability to influence accumulation of T cells within skin, a tissue in which CCR9 plays no known role, and we found no appreciable effect. This study demonstrates the feasibility of creating systemically-administered pharmaceuticals capable of tissue-selective immune modulation. This proof of concept is of utmost importance for designing effective treatments against various autoimmune disorders localized to a specific tissue

    The early UL3 gene of equine herpesvirus-1 encodes a tegument protein not essential for replication or virulence in the mouse

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    AbstractThe UL3 gene of equine herpesvirus-1 (EHV-1) is retained in the genome of defective interfering particles and encodes a ~33kDa myristylated protein. Further characterization showed that the UL3 gene is trans-activated only by the sole immediate early (IE) protein and encodes an early protein that is dispensable for EHV-1 replication and localizes in the tegument of purified virions. UL3-deleted EHV-1 (vL11ΔUL3) exhibits properties of host cell tropism, plaque size, and growth kinetics similar to those of the parental virus. Expression levels of EHV-1 proteins representative of all three gene classes in vL11ΔUL3-infected cells were identical to those in cells infected with parental virus. Mice intranasally infected with vL11ΔUL3 and parental virus showed no significant difference in mortality or virus lung titers. These findings suggest that the UL3 protein does not play a major role in the biology of EHV-1 in cell culture or virulence in the mouse

    Evaluation of Cardiovascular Risk Scores Applied to NASA's Astronant Corps

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    In an effort to improve cardiovascular disease (CVD) risk prediction, this analysis evaluates and compares the applicability of multiple CVD risk scores to the NASA Astronaut Corps which is extremely healthy at selection

    The profession of authorship in America, 1800-1870: the papers of William Charvat

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    (print) xviii, 327 p. : facsim., port. ; 27 cm"Checklist: the publications of William Charvat": p. [317]-319. Includes bibliographical referencesI. Introduction 3 -- II. The Beginnings of Professionalism 5 -- III. The Conditions of Authorship in 1820 29 -- IV. American Romanticism and the Depression of 1837 (1937) 49 -- V. Cooper as Professional Author (1954) 68 -- VI. Poe : Journalism and the Theory of Poetry (1962) 84 -- VII. The Popularization of Poetry 100 -- VIII. Longfellow 106 -- IX. Longfellow's Income from His Writings, 1842-1852 (1944) 155 -- X. James T. Fields and the Beginnings of Book Promotion (1954) 168 -- XI. Melville's Income (1943) 190 -- XII. Melville 204 -- XIII. Melville and the Common Reader (1958) 262 -- XIV. Literary Economics and Literary History (1950) 283 -- XV. The People's Patronage (1948) 298 -- Checklist : The Publications of William Charvat 317 -- Index 32

    High Performance EVA Glove Collaboration: Glove Injury Data Mining Effort

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    Human hands play a significant role during Extravehicular Activity (EVA) missions and Neutral Buoyancy Lab (NBL) training events, as they are needed for translating and performing tasks in the weightless environment. Because of this high frequency usage, hand and arm related injuries are known to occur during EVA and EVA training in the NBL. The primary objectives of this investigation were to: 1) document all known EVA glove related injuries and circumstances of these incidents, 2) determine likely risk factors, and 3) recommend interventions where possible that could be implemented in the current and future glove designs. METHODS: The investigation focused on the discomforts and injuries of U.S. crewmembers who had worn the pressurized Extravehicular Mobility Unit (EMU) spacesuit and experienced 4000 Series or Phase VI glove related incidents during 1981 to 2010 for either EVA ground training or in-orbit flight. We conducted an observational retrospective case-control investigation using 1) a literature review of known injuries, 2) data mining of crew injury, glove sizing, and hand anthropometry databases, 3) descriptive statistical analyses, and finally 4) statistical risk correlation and predictor analyses to better understand injury prevalence and potential causation. Specific predictor statistical analyses included use of principal component analyses (PCA), multiple logistic regression, and survival analyses (Cox proportional hazards regression). Results of these analyses were computed risk variables in the forms of odds ratios (likelihood of an injury occurring given the magnitude of a risk variable) and hazard ratios (likelihood of time to injury occurrence). Due to the exploratory nature of this investigation, we selected predictor variables significant at p0.15. RESULTS: Through 2010, there have been a total of 330 NASA crewmembers, from which 96 crewmembers performed 322 EVAs during 1981-2010, resulting in 50 crewmembers being injured inflight and 44 injured during 11,704 ground EVA training events. Of the 196 glove related injury incidents, 106 related to EVA and 90 to EVA training. Over these 196 incidents, 277 total injuries (126 flight; 151 training) were reported and were then grouped into 23 types of injuries. Of EVA flight injuries, 65% were commonly reported to the hand (in general), metacarpophalangeal (MCP) joint, and finger (not including thumb) with fatigue, abrasion, and paresthesia being the most common injury types (44% of total flight injuries). Training injuries totaled to more than 70% being distributed to the fingernail, MCP joint, and finger crotch with 88% of the specific injuries listed as pain, erythema, and onycholysis. Of these training injuries, when reporting pain or erythema, the most common location was the index finger, but when reporting onycholysis, it was the middle finger. Predictor variables specific to increased risk of onycholysis included: female sex (OR=2.622), older age (OR=1.065), increased duration in hours of the flight or training event (OR=1.570), middle finger length differences in inches between the finger and the EVA glove (OR=7.709), and use of the Phase VI glove (OR=8.535). Differentiation between training and flight and injury reporting during 2002-2004 were significant control variables. For likelihood of time to first onycholysis injury, there was a 24% reduction in rate of reporting for each year increase in age. Also, more experienced crewmembers, based on number of EVA flight or training events completed, were less likely to report an onycholysis injury (3% less for every event). Longer duration events also found reporting rates to occur 2.37 times faster for every hour of length. Crewmembers with larger hand size reported onycholysis 23% faster than those with smaller hand size. Finally, for every 1/10th of an inch increase in difference between the middle finger length and the glove, the rate of reporting increased by 60%. DISCUSSION: One key finding was that the Series 4000 glove had a lower injury risk than the Phase VI, which provides a platform for further evaluation. General interventions that reduce hand overexertion and repetitive use exposure through tool development, procedural changes and shorter exposures may be one mitigation path, but due to the way the training event times were reported, we cannot provide a guideline for a specific event duration change. When the finger length was different from the glove length, the risk of injury increased indicating that the use of larger finger take-ups could be contributing to injury and therefore may not be recommended. Prior to this investigation, there was one previous investigation indicating hand anthropometry may be related to onycholysis. We found different hand anthropometry variables indicated by this investigation as compared to the prior, specifically differences in middle finger length compared to glove finger length, which point more towards a sizing issue than a specific anthropometry issue. Additionally, although this investigation has identified sizing as an issue, the force and environmental-related variables of the EVA glove that could also cause injury were not accounted for

    TgDrpC, an atypical dynamin‐related protein in Toxoplasma gondii, is associated with vesicular transport factors and parasite division

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    Dynamin‐related proteins (Drps) are involved in diverse processes such as organelle division and vesicle trafficking. The intracellular parasite Toxoplasma gondii possesses three distinct Drps. TgDrpC, whose function remains unresolved, is unusual in that it lacks a conserved GTPase Effector Domain, which is typically required for function. Here, we show that TgDrpC localizes to cytoplasmic puncta; however, in dividing parasites, TgDrpC redistributes to the growing edge of the daughter cells. By conditional knockdown, we determined that loss of TgDrpC stalls division and leads to rapid deterioration of multiple organelles and the IMC. We also show that TgDrpC interacts with proteins that exhibit homology to those involved in vesicle transport, including members of the adaptor complex 2. Two of these proteins, a homolog of the adaptor protein 2 (AP‐2) complex subunit alpha‐1 and a homolog of the ezrin–radixin–moesin (ERM) family proteins, localize to puncta and associate with the daughter cells. Consistent with the association with vesicle transport proteins, re‐distribution of TgDrpC to the IMC during division is dependent on post‐Golgi trafficking. Together, these results support that TgDrpC contributes to vesicle trafficking and is critical for stability of parasite organelles and division

    Access to Archived Astronaut Data for Human Research Program Researchers: Update on Progress and Process Improvements

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    Since the 2010 NASA directive to make the Life Sciences Data Archive (LSDA) and Lifetime Surveillance of Astronaut Health (LSAH) data archives more accessible by the research and operational communities, demand for astronaut medical data has increased greatly. LSAH and LSDA personnel are working with Human Research Program on many fronts to improve data access and decrease lead time for release of data. Some examples include the following: Feasibility reviews for NASA Research Announcement (NRA) data mining proposals; Improved communication, support for researchers, and process improvements for retrospective Institutional Review Board (IRB) protocols; Supplemental data sharing for flight investigators versus purely retrospective studies; Work with the Multilateral Human Research Panel for Exploration (MHRPE) to develop acceptable data sharing and crew consent processes and to organize inter-agency data coordinators to facilitate requests for international crewmember data. Current metrics on data requests crew consenting will be presented, along with limitations on contacting crew to obtain consent. Categories of medical monitoring data available for request will be presented as well as flow diagrams detailing data request processing and approval steps
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