485 research outputs found

    Design strategies for the International Space University's variable gravity research facility

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    A variable gravity research facility named 'Newton' was designed by 58 students from 13 countries at the International Space University's 1989 summer session at the Universite Louis Pasteur, Strasbourge, France. The project was comprehensive in scope, including a political and legal foundation for international cooperation, development and financing; technical, science and engineering issues; architectural design; plausible schedules; and operations, crew issues and maintenance. Since log-term exposure to zero gravity is known to be harmful to the human body, the main goal was to design a unique variable gravity research facility which would find a practical solution to this problem, permitting a manned mission to Mars. The facility would not duplicate other space-based facilities and would provide the flexibility for examining a number of gravity levels, including lunar and Martian gravities. Major design alternatives included a truss versus a tether based system which also involved the question of docking while spinning or despinning to dock. These design issues are described. The relative advantages or disadvantages are discussed, including comments on the necessary research and technology development required for each

    The International Space University's variable gravity research facility design

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    A manned mission to Mars will require long travel times between Earth and Mars. However, exposure to long-duration zero gravity is known to be harmful to the human body. Some of the harmful effects are loss of heart and lung capacity, inability to stand upright, muscular weakness and loss of bone calcium. A variable gravity research facility (VGRF) that would be placed in low Earth orbit (LEO) was designed by students of the International Space University 1989 Summer Session held in Strasbourg, France, to provide a testbed for conducting experiments in the life and physical sciences in preparation for a mission to Mars. This design exercise was unique because it addressed all aspects concerning a large space project. The VGRF design was described which was developed by international participants specializing in the following areas: the politics of international cooperation, engineering, architecture, in-space physiology, material and life science experimentation, data communications, business, and management

    Cloud Chamber: A Performance with Real Time Two-Way Interaction between Subatomic Particles and Violinist

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    ‘Cloud Chamber’ - a composition by Alexis Kirke, Antonino Chiaramonte, and Anna Troisi - is a live performance in which the invisible quantum world becomes visible as a violinist and subatomic particle tracks interact together. An electronic instrument was developed which can be “played” live by radioactive atomic particles. Electronic circuitry was developed enabling a violin to create a physical force field that directly affects the ions generated by cosmic radiation particles. This enabled the violinist and the ions to influence each other musically in real time. A glass cloud chamber was used onstage to make radioactivity visible in bright white tracks moving within, with the tracks projected onto a large screen

    Quantification of the mycorrhizal fungal community associated with a modern wheat cultivar (Triticum aestivum) and with a wheat ancestor.

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    Abstract: Plant breeding is an important instrument to improve crop productivity. However, studies have shown that plant breeding, as well as the use of management practices such as tillage and fertilization, influence the plant root microbiome and also may have caused reduction in the genetic diversity of modern cultivars when compared to their ancestors. As the rhizosphere microbiome can profoundly impact plant growth, nutrition and health, we hypothesized that plant breeding can negatively affect the recruitment of beneficial microbes in the rhizosphere and interactions with their favorable microbial partners. A greenhouse experiment was conducted to assess the composition of the rhizosphere mycorrhizal fungi community in wheat (Triticum aestivum) varieties, modern cultivars and wheat ancestors. Plants were grown in forest and agricultural soils, collected in wheat cultivation area in São Paulo, Brazil. The DNA was extracted from rhizospheric soil collected in the flowering stage, and the r RNA 18S gene copy number of mycorrhizal fungi was determined using quantitative real-time PCR (qPCR). The bulk soil presented less mycorrhizal fungi than rhizospheric soil of modern cultivars and more than rhizospheric soil of wheat ancestors indicating that these materials can be more selective in recruiting and structuring the rhizosphere microbiome. Modern cultivars were more intensely colonized by mycorrhizal fungi compared to ancestral genotypes and therefore possibly more dependent on these microorganisms. The results do not evidence that new crop plant genotypes lost their ability to respond to mycorrhizal due to agricultural and breeding practices, and further analyses needs to be performed

    Effect of phosphorus limitation on the microbial community assembly in the common bean (Phaseolus vulgaris L.) rhizosphere.

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    Abstract: The indiscriminate use of inputs in agricultural systems, particularly phosphate, combined with the need of growing food production, is causing the depletion of phosphorus mines around the world. In order to mitigate the environmental impact caused by phosphorus exploration microorganisms can be used to increase the efficiency of phosphorus utilization in crop systems by promoting nutrient solubilization and absorption. It is believed that low phosphorus concentration in soil, enriches specific members of the rhizosphere microbiome related to the availability of this element to the plant. In this study, a factorial experiment was performed considering contrasting cultivars in the uptake efficiency of phosphorus (being IAC-Imperador and DOR-364, the cultivar with high and low efficiency in P uptake); using soil with low P content and enriched concentrations of rock phosphate and single superphosphate. The rhizosphere microbiome was accessed using TSA and NBRIP media, to estimate total bacterial colony-forming units and identify isolates with potential of P solubilization, respectively. Total DNA was extracted and mycorrhizal fungi community was quantified using qPCR. The number of total bacteria colony-forming unit increased in the single superphosphate treatments of the IAC-Imperador (p<0.01), but not in DOR-364. Phosphorus solubilizing bacteria abundance also showed increase in single superphosphate treatments in both cultivars (p<0.01). Rock phosphate treatments did not showed any significant differences in colony-forming unit abundances. When considering the cultivar with higher efficiency in phosphorus uptake, the abundance of mycorrhizal fungi did not differed significantly. On the other hand, the lower efficient cultivar showed 5-fold increase with the addition of single superphosphate, and a 10-fold increase with rock phosphate (p<0.01). The results suggest that different type of P and the plant variety assembles the microbial community that helps plants in P uptake. The recruitment of mycorrhizal fungi is higher in the cultivar less efficient in phosphorus uptake, mainly when in the presence of phosphate rock

    Antinuclear antibodies (ANA) in chronic hepatitis C virus infection: correlates of positivity and clinical relevance.

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    We examined correlates of antinuclear antibody (ANA) positivity (ANA+) in individuals with chronic hepatitis C virus (HCV) infection and the effect of positivity on clinical outcome of HCV. Pretreatment sera from 645 patients from three centres in Sweden (n = 225), the UK (n = 207) and Italy (n = 213) were evaluated by indirect immunofluorescence on Hep-2 cells for ANA pattern and titre by a single laboratory. Liver biopsies were all scored by one pathologist. A total of 258 patients were subsequently treated with interferon monotherapy. There was a significant difference in the prevalence of ANA (1:40) by geographic location: Lund 4.4%, London 8.7%, Padova 10.3% [odds ratio (OR) = 0.66; 95% CI: 0.46-0.94; P = 0.023]. Duration of HCV infection, age at infection, current age, route of infection, viral genotype, alcohol consumption, fibrosis stage and inflammatory score were not correlated with ANA+ or ANA pattern. Female gender was correlated with ANA+ and this association persisted in multivariable analyses (OR = 3.0; P = 0.002). Increased plasma cells were observed in the liver biopsies of ANA-positive individuals compared with ANA-negative individuals, while a trend towards decreased lymphoid aggregates was observed [hazard ratio (HR) = 9.0, P = 0.037; HR = 0.291, P = 0.118, respectively]. No correlations were observed between ANA positivity and nonresponse to therapy (OR = 1.4; P = 0.513), although ANA+ was correlated with faster rates of liver fibrosis, this was not statistically significant (OR = 1.8; P = 0.1452). Low titre ANA+ should not be a contraindication for interferon treatment. Our observation of increased plasma cells in ANA+ biopsies might suggest B-cell polyclonal activity with a secondary clinical manifestation of increased serum immunoglobulins

    The NASA Microgravity Fluid Physics Program: Research Plans for the ISS

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    Building on over four decades of research and technology development related to the behavior of fluids in low gravity environments, the current NASA Microgravity Fluid Physics Program continues the quest for knowledge to further understand and design better fluids systems for use on earth and in space. NASA's Biological and Physical Research Enterprise seeks to exploit the space environment to conduct research supporting human exploration of space (strategic research), research of intrinsic scientific importance and impact (fundamental research), and commercial research. The strategic research thrust will build the vital knowledge base needed to enable NASA's mission to explore the Universe and search for life. There are currently five major research areas in the Microgravity Fluid Physics Program: complex fluids, niultiphase flows and phase change, interfacial phenomena, biofluid mechanics, and dynamics and instabilities. Numerous investigations into these areas are being conducted in both ground-based laboratories and facilities and in the flight experiments program. Most of the future NASA- sponsored flight experiments in microgravity fluid physics and transport phenomena will be carried out on the International Space Station (ISS) in the Fluids Integrated Rack (FIR), in the Microgravity Science Glovebox (MSG), in EXPRESS racks, and in other facilities provided by international partners. This paper presents an overview of the near- and long-term visions for NASA's Microgravity Fluid Physics Research Program and brief descriptions of hardware systems planned to enable this research

    Dipturus argentinensis, argentine skate

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    The Argentine Skate (Dipturus argentinensis) occurs in the Southwest Atlantic from central Chubut to southern Santa Cruz, Argentina and off the northwest Falkland Islands (Malvinas). It inhabits continental and insular shelves and slopes at depths of 85–400 m. Maximum size is unknown as only immature specimens have been caught (up to 125 cm total length) and there is some question as to where the adult population occurs. This skate is captured in commercial demersal trawl fisheries, which are intense across its entire known geographic and bathymetric range. It is captured in the target trawl fishery for skates off the Falkland Islands (Malvinas). Identification is an issue, and it may be captured more than is perceived. More information is needed to determine the level of overlap with fisheries and this species' catchability and sensitivity to fishing. Research is needed on distribution, life history, population size and trends, and threats. Since it is unknown whether fishing is causing a population reduction, there is currently inadequate information available to assess the Argentine Skate beyond Data Deficient.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Pompert, J.. Georgia Seafoods; Países BajosFil: Herman, K.. Georgia Aquarium; Estados Unido
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