42 research outputs found

    Spacelab 3 mission

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    Spacelab-3 (SL-3) was the first microgravity mission of extended duration involving crew interaction with animal experiments. This interaction involved sharing the Spacelab environmental system, changing animal food, and changing animal waste trays by the crew. Extensive microbial testing was conducted on the animal specimens and crew and on their ground and flight facilities during all phases of the mission to determine the potential for cross contamination. Macroparticulate sampling was attempted but was unsuccessful due to the unforseen particulate contamination occurring during the flight. Particulate debris of varying size (250 micron to several inches) and composition was recovered post flight from the Spacelab floor, end cones, overhead areas, avionics fan filter, cabin fan filters, tunnel adaptor, and from the crew module. These data are discussed along with solutions, which were implemented, for particulate and microbial containment for future flight facilities

    Lunar Regolith Biomining: Workshop Report

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    On May 5th and 6th, 2007, NASA Ames Research Center hosted a workshop entitled 'Lunar Regolith Biomining'. The workshop addressed the feasibility of biologically-based mining of the lunar regolith along with identification of views and concepts for moving this topic forward to NASA. Workshop presentations provided background in topics of interest that served as the foundation for discussion in the subsequent breakout sessions. The first topical area included the history, status, and issues with biomining on Earth to familiarize all attendees with current activities. These presentations related the primary considerations in existing biomining, e.g., microbes of choice, pH of reactions, time and temperature, specific mining applications and locations, and benefits and/or limitations of biomining. The second area reviewed existing research efforts addressing biomining of planetary surfaces (Mars, Moon), including microbial considerations, and chemical necessities in biomining and biofuel production. The last element pertained to other non-biological considerations and influences in biomining efforts on the lunar surface such as radiation fluxes and effects, and the application of small satellite experiments to learn more about the lunar and Martian surfaces. Following the presentations, the workshop attendees divided into three breakout sessions to discuss areas of interest in greater detail and to define next steps in determining the feasibility of lunar regolith biomining. Topics for each of the three breakout sessions included: 1) bio-communities of choice, target product(s), and suggested ground studies; 2) physical/environmental issues and ground studies; and 3) the development of reference experiments for the Astrobiology Small payloads Workshop. The results of the breakout sessions are summarized and a list of participants is included

    Studies of a Halophilic NADH Dehydrogenase. 1: Purification and Properties of the Enzyme

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    An NADH dehydrogenase obtained from an extremely halophilic bacterium was purified 570-fold by a combination of gel filtration, chromatography on hydroxyapatite, and ion-exchange chromatography on QAE-Sephadex. The purified enzyme appeared to be FAD-linked and bad an apparent molecular weight of 64000. Even though enzyme activity was stimulated by NaCl, considerable activity (430 % of the maximum activity observed in the presence of 2.5 M NaCl) was observed in the absence of added NaCl. The enzyme was unstable when incubated in solutions of low ionic strength. The presence of NADH enhanced the stability of the enzyme

    A Review of Some Aspects of L-Forms and Gonococci

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    Systemic manifestations of gonococcal disease, such as arthritis, are often sterile on the usual culture methods used to grow gonococci. Allergic mechanisms have been invoked to explain this but with little evidence to support the concept. With the report by Holmes et al., that L-forms of gonococci were isolated from joint fluid of a patient with gonococcal arthritis, we decided to investigate the possible role of L-forms in gonococcal disease

    Spacelab Life Sciences-1

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    This report provides an historical overview of the Spacelab Life Sciences-1 (SLS-1) mission along with the resultant biomaintenance data and investigators' findings. Only the nonhuman elements, developed by Ames Research Center (ARC) researchers, are addressed herein. The STS-40 flight of SLS-1, in June 1991, was the first spacelab flown after 'return to orbit', it was also the first spacelab mission specifically designated as a Life Sciences Spacelab. The experiments performed provided baseline data for both hardware and rodents used in succeeding missions

    Longitudinal grey and white matter changes in frontotemporal dementia and Alzheimer's disease

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    Behavioural variant frontotemporal dementia (bvFTD) and Alzheimer's disease (AD) dementia are characterised by progressive brain atrophy. Longitudinal MRI volumetry may help to characterise ongoing structural degeneration and support the differential diagnosis of dementia subtypes. Automated, observer-independent atlas-based MRI volumetry was applied to analyse 102 MRI data sets from 15 bvFTD, 14 AD, and 10 healthy elderly control participants with consecutive scans over at least 12 months. Anatomically defined targets were chosen a priori as brain structures of interest. Groups were compared regarding volumes at clinic presentation and annual change rates. Baseline volumes, especially of grey matter compartments, were significantly reduced in bvFTD and AD patients. Grey matter volumes of the caudate and the gyrus rectus were significantly smaller in bvFTD than AD. The bvFTD group could be separated from AD on the basis of caudate volume with high accuracy (79% cases correct). Annual volume decline was markedly larger in bvFTD and AD than controls, predominantly in white matter of temporal structures. Decline in grey matter volume of the lateral orbitofrontal gyrus separated bvFTD from AD and controls. Automated longitudinal MRI volumetry discriminates bvFTD from AD. In particular, greater reduction of orbitofrontal grey matter and temporal white matter structures after 12 months is indicative of bvFTD

    Com o diabo no corpo: os terrĂ­veis papagaios do Brasil colĂŽnia

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    Desde a Antiguidade, papagaios, periquitos e afins (Psittacidae) fascinaram os europeus por seu vivo colorido e uma notĂĄvel capacidade de interação com seres humanos. A descoberta do Novo Mundo nada faria alĂ©m de acrescentar novos elementos ao trĂĄfico de animais exĂłticos hĂĄ muito estabelecido pelos europeus com a África e o Oriente. Sem possuir grandes mamĂ­feros, a AmĂ©rica tropical participaria desse comĂ©rcio com o que tinha de mais atrativo, essencialmente felinos, primatas e aves - em particular os papagaios, os quais eram embarcados em bom nĂșmero. Contudo, a julgar pelos documentos do Brasil colĂŽnia, esses volĂĄteis podiam inspirar muito pouca simpatia, pois nenhum outro animal - exceto as formigas - foi tantas vezes mencionado como praga para a agricultura. AlĂ©m disso, alguns psitĂĄcidas mostravam-se tĂŁo loquazes que inspiravam a sĂ©ria desconfiança de serem animais demonĂ­acos ou possessos, pois sĂł trĂȘs classes de entidades - anjos, homens e demĂŽnios - possuĂ­am o dom da palavra. Nos dias de hoje, vĂĄrios representantes dos Psittacidae ainda constituem uma ameaça para a agricultura, enquanto os indivĂ­duos muito faladores continuam despertando a suspeita de estarem possuĂ­dos pelo demĂŽnio. Transcendendo a mera curiosidade, essa crença exemplifica o quĂŁo intrincadas podem ser as relaçÔes do homem com o chamado “mundo natural”, revelando um universo mais amplo e multifacetado do que se poderia supor a princĂ­pio. Nesse sentido, a existĂȘncia de aves capazes de falar torna essa relação ainda mais complexa e evidencia que as dificuldades de estabelecer o limite entre o animal e o humano se estendem alĂ©m dos primatas e envolvem as mais inusitadas espĂ©cies zoolĂłgicas.Since ancient times, parrots and their allies (Psittacidae) have fascinated Europeans by their striking colors and notable ability to interact with human beings. The discovery of the New World added new species to the international exotic animal trade, which for many centuries had brought beasts to Europe from Africa and the Orient. Lacking large mammals, tropical America participated in this trade with its most appealing species, essentially felines, primates and birds - especially parrots - which were shipped in large numbers. It should be noted, however, that at times these birds were not well liked. In fact, according to documents from colonial Brazil, only the ants rank higher than parrots as the animals most often mentioned as agricultural pests. On the other hand, some of these birds were so chatty that people suspected them to be demonic or possessed animals, since only three classes of beings - angels, men and demons - have the ability to speak. Nowadays, several Psittacidae still constitute a threat to agriculture, and the suspicion that extremely talkative birds were demon possessed has also survived. More than a joke or a mere curiosity, this belief exemplifies how intricate man’s relationships with the “natural world” may be. In this sense, the existence of birds that are able to speak adds a further twist to these relationships, demonstrating that the problem of establishing a boundary between the animal and the human does not only involve primates, but also includes some unusual zoological species

    Three Dimensional Cross-Sectional Properties From Bone Densitometry

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    Bone densitometry has previously been used to obtain cross-sectional properties of bone in a single scan plane. Using three non-coplanar scans, we have extended the method to obtain the principal area Moments of inertia and orientations of the principal axes at each cross-section along the length of the scan. Various 5 aluminum phantoms were used to examine scanner characteristics to develop the highest accuracy possible for in vitro non-invasive analysis of mass distribution. Factors considered included X-ray photon energy, initial scan orientation, the included angle of the 3 scans, and Imin/Imax ratios. Principal moments of inertia were accurate to within 3.1% and principal angles were within 1 deg. of the expected value for phantoms scanned with included angles of 60 deg. and 90 deg. at the higher X-ray photon energy. Low standard deviations in error also 10 indicate high precision of calculated measurements with these included angles. Accuracy and precision decreased slightly when the included angle was reduced to 30 deg. The method was then successfully applied to a pair of excised cadaveric tibiae. The accuracy and insensitivity of the algorithms to cross-sectional shape and changing isotropy (Imin/Imax) values when various included angles are used make this technique viable for future in vivo studies

    Neurolab: Final Report for the Ames Research Center Payload

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    Neurolab, the final Spacelab mission, launched on STS-90 on April 17, 1998, was dedicated to studying the nervous system. NASA cooperated with domestic and international partners to conduct the mission. ARC's (Ames Research Center's) Payload included 15 experiments designed to study the adaptation and development of the nervous system in microgravity. The payload had the largest number of Principal and Co-Investigators, largest complement of habitats and experiment unique equipment flown to date, and most diverse distribution of live specimens ever undertaken by ARC, including rodents, toadfish, swordtail fish, water snails, hornweed and crickets To facilitate tissue sharing and optimization of science objectives, investigators were grouped into four science discipline teams: Neuronal Plasticity, Mammalian Development, Aquatic, and Neurobiology. Several payload development challenges were experienced and required an extraordinary effort, by all involved, to meet the launch schedule. With respect to hardware and the total amount of recovered science, Neurolab was regarded as an overall success. However, a high mortality rate in one rodent group and several hardware anomalies occurred inflight that warranted postflight investigations. Hardware, science, and operations lessons were learned that should be taken into consideration by payload teams developing payloads for future Shuttle missions and the International Space Station
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