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361.
The influence of microgravity on lymphocyte activation is central to the understanding of immunological function in space. Moreover, the adaptation of groundbased technologies to microgravity conditions presents opportunities for biotechnological applications including high efficiency production of antibody forming hybridomas. Because the emerging technology of microgravity hybridoma generation is dependent upon activation and cultivation of B lymphocytes during flight, we have adapted mitogen-driven B lymphocyte stimulation and culture that allows for the in vitro generation of large numbers of antibody forming cells suitable for cell fusion over a period of 1-2 weeks. We believe that this activation and cultivation system can be flown on near-term space flights to test fundamental hypotheses about mammalian cell activation, cell fusion, metabolism, secretion, growth, and bio-separation.  相似文献   
362.
A newly developed balloon-borne cryogenic sampler has been used to collect large air samples in the midlatitude stratosphere (44° N). The samples were analysed for their content of several longlived trace gases. The vertical profiles of N2O, CH4, and CF2Cl2 derived from two balloon flights in winter 1982 and, as part of the MAP Globus Project, in fall 1983 indicate variations that are caused by large scale dynamic processes. Significant features of the profiles are discussed and compared with averaged profiles that were derived from a series of balloon sampling flights performed previously over the same location during the summer season. The temporal variation of the individual profiles is more detailed than predicted by model calculations.  相似文献   
363.
364.
Culbertson F 《Acta Astronautica》2004,54(11-12):793-797
The Commander of the International Space Station Expedition Three describes what the space station looks like. The tour includes the American communications link, the Express rack for science experiments, the Node with its collapsible water containers, the Airlock, the FGB, and living space in the Service Module.  相似文献   
365.
Bluem V  Paris F 《Acta Astronautica》2002,50(12):775-785
The closed equilibrated biological aquatic system (C.E.B.A.S) is a man-made aquatic ecosystem which consists of four subcomponents: an aquatic animal habitat, an aquatic plant bioreactor, an ammonia oxidizing bacteria filter and a data acquisition/control unit. It is a precursor for different types of fish and aquatic plant production sites which are disposed for the integration into bioregenerative life-support systems. The results of two successful spaceflights of a miniaturized C.E.B.A.S version (the C.E.B.A.S. MINI MODULE) allow the optimization of aquatic food production systems which are already developed in the ground laboratory and open new aspects for their utilization as aquatic modules in space bioregenerative life support systems. The total disposition offers different stages of complexity of such aquatic modules starting with simple but efficient aquatic plant cultivators which can be implemented into water recycling systems and ending up in combined plant/fish aquaculture in connection with reproduction modules and hydroponics applications for higher land plants. In principle, aquaculture of fishes and/or other aquatic animals edible for humans offers optimal animal protein production under lowered gravity conditions without the tremendous waste management problems connected with tetrapod breeding and maintenance. The paper presents details of conducted experimental work and of future dispositions which demonstrate clearly that aquaculture is an additional possibility to combine efficient and simple food production in space with water recycling utilizing safe and performable biotechnologies. Moreover, it explains how these systems may contribute to more variable diets to fulfill the needs of multicultural crews.  相似文献   
366.
Because of their different origins, cosmic rays can be subdivided into galactic cosmic rays and solar/stellar cosmic rays. The flux of cosmic rays to planetary surfaces is mainly determined by two planetary parameters: the atmospheric density and the strength of the internal magnetic moment. If a planet exhibits an extended magnetosphere, its surface will be protected from high-energy cosmic ray particles. We show that close-in extrasolar planets in the habitable zone of M stars are synchronously rotating with their host star because of the tidal interaction. For gravitationally locked planets the rotation period is equal to the orbital period, which is much longer than the rotation period expected for planets not subject to tidal locking. This results in a relatively small magnetic moment. We found that an Earth-like extrasolar planet, tidally locked in an orbit of 0.2 AU around an M star of 0.5 solar masses, has a rotation rate of 2% of that of the Earth. This results in a magnetic moment of less than 15% of the Earth's current magnetic moment. Therefore, close-in extrasolar planets seem not to be protected by extended Earth-like magnetospheres, and cosmic rays can reach almost the whole surface area of the upper atmosphere. Primary cosmic ray particles that interact with the atmosphere generate secondary energetic particles, a so-called cosmic ray shower. Some of the secondary particles can reach the surface of terrestrial planets when the surface pressure of the atmosphere is on the order of 1 bar or less. We propose that, depending on atmospheric pressure, biological systems on the surface of Earth-like extrasolar planets at close-in orbital distances can be strongly influenced by secondary cosmic rays.  相似文献   
367.
Manned spaceflight has been an important element of the German space program over the last decades. This is demonstrated by the nationally managed space missions Spacelab D-l (1985), D-2 (1993), and MIR '92 as well as by the participation in the 1st Spacelab mission FSLP (1983), the NASA missions IML-1 (1992) and IML-2 (1994), as well as in the ESA missions EUROMIR '94 and '95. On February 12th, this year, the German cosmonaut Reinhold Ewald was launched together with his Russian colleagues Wasilij Zibliew and Alexander Lasudkin onboard of a Soyuz spacecraft for another stay of a German cosmonaut onboard of the Russian Space Station MIR. This mission--the so-called German/Russian MIR '97--was, of course, another cornerstone with regard to the cooperation between Russian and German space organizations. The cooperation in the area of manned missions began 1978 with the flight of the German cosmonaut Sigmund Jahn onboard of Salyut 6, at that time a cooperation between the Soviet Union and the German Democratic Republic in the frame of the Interkosmos Program. In March 1992, it was followed by the flight of Klaus Dietrich Flade with his stay onboard of MIR. After two further successful ESA missions, EUROMIR '94 and '95 with the two German cosmonauts Ulf Merbold and Thomas Reiter and with a marked contribution of German scientists, the decision was taken to perform another German/Russian MIR mission, the so-called MIR '97. In Germany, MIR'97 was managed and performed in a joint effort between several partners. DARA, the German Space Agency, was responsible for the overall program and project management, while DLR, the German Aerospace Research Establishment, was responsible for the cosmonaut training, for medical operations, for the mission control at GSOC in Oberpfaffenhofen as well as for user support.  相似文献   
368.
Private and commercial activity in outer space still poses challenges to space law and policy. Within ‘Project 2001’—a legal research project by the University of Cologne's Institute of Air and Space Law and the German Aerospace Center (DLR)—six international expert working groups examined international and national laws, in order to identify gaps and, where necessary, propose improvements to the present legal framework for private space activities. The results were presented and discussed at an international colloquium in May 2001 in Cologne, Germany, where final conclusions have been drawn. This report presents a summary of the project's work and main conclusions, which are documented in full in a comprehensive book to be published in May 2002.  相似文献   
369.
This paper reviews shortly the results obtained by a preliminary call for experiment proposals for future Spacelab flights issued by the European Space Agency in April 1978. The results of this call indicate clearly the trend towards experiments performing studies on the state and the evolution of fluid media. The instrumentation used are mainly multipurpose instruments (furnaces, process chambers) already under development for the first Spacelab flight and new equipment currently under study.  相似文献   
370.
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