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1.
国产卤虫(Artemia salina)卵经“8799”卫星搭载空间飞行8天,回收后155天内定期随机取卵,行人工孵化及发育观察.结果是:(1)观察到飞行卵早期发育速度显著延缓,及随回收后卵保存时间的延长呈现恢复的趋势;(2)飞行卵总孵出率及孵出卤虫的存活情况与现场对照组相似;(3)地面超重力模拟实验未显示其对卤虫胚胎发育的明显影响.作者强调了现场对照的必要性,并考虑到空间飞行中微重力的可能重要作用.  相似文献   

2.
为了能够估价空间重粒子对单个生物细胞的放射生物学效应,我们设计、制成了卤虫卵-核乳胶夹层式生物包.经搭载我国“8885”卫星飞行数天后回收.用图象分析仪研究了空间重离子在核乳胶上留下的径迹及其分布;并实验观察了卤虫卵的前期发育情况.看到:随星飞行过的卤虫卵与地面对照组相比,其发育能力明显降低,表现为孵化率低且发育时间推迟.实验表明:生物样品板-核乳胶影象定位技术能清楚而比较准确地给出卤虫卵(或其他生物细胞)受重离子作用的信息,是重离子生物效应及其作用机理研究的可行实验手段及分析方法之一.  相似文献   

3.
用黑腹果蝇检查T7A—S1火箭飞行因素的遗传效应。通过两次飞行实验观察,发现亲代雌蝇在飞行后(主要是第4—6天)所产的卵中,无X染色体卵百分率增高而双X染色体卵百分率未见变化。其性质并非个别雌蝇产生了较多的无X染色体卵,而是产生无X染色体卵的雌蝇个数增多。第二次飞行实验结果也呈现,亲代雌蝇在飞行后第4—6天所产的子1代中,三龄幼虫成神经细胞染色体桥频率增高。上述实验结果表明,火箭飞行因素对雌果蝇生殖细胞遗传物质有轻微影响。   相似文献   

4.
7月份,苏法两国签订了空间合作附加议定书,以延长1966年6月政府间空间合作协定。特别是在扩大载人飞行合作、航天飞机地面试验、研究地球环境及火星探索方面。双方原则决定1992年第二季度法国宇航员登上和平号空间站进行医学和生理实验、电泳和流体实验。这将是法苏第三次载人联合飞行。飞行时间为14天,2天在联盟号飞船上,12天在和平号空间站上。但在费  相似文献   

5.
2月28日美国东部时间上午2:50,阿特兰蒂斯号航天飞机从肯尼迪中心起飞,执行第36次飞行任务。航天飞机在110海里高、62度倾角的轨道上飞行,这是美国航天飞机迄今为止飞行的轨道倾角最大的。在飞行18圈时,即入轨后27小时,航天飞机释放了双重使命的AFP-731侦察/情报卫星。 AFP/731卫星重37300磅,设计寿命5年。国防部拟在卫星寿命结束前,进行首次空间加燃,延长它的寿命3年。而后回收或在轨更换部件,再次使用。卫星上装有数字图像摄像机,能精确拍摄地面目标,如潜艇船坞和  相似文献   

6.
美国发现号航天飞机于1992年12月2日美国东部标准时间8时24分(格林尼治时间13时24分)从肯尼迪空间中心发射升空。这是美国航天飞机的第52次飞行及发现号航天飞机的第14次飞行,飞行任务代号为STS-53。因发射前气温降至-11℃,航天飞机外燃料贮箱上形成了霜和少量的冰,为等待太阳晒暖航天飞机,发射推迟了85分钟(按照1986年挑战者号航天飞机失事后NASA制定的标准,如果环境温度下降至-11.44℃或以下,并持续30分钟以上,发射前倒计数即应停止)。发现号航天飞机的上次飞行是1992年1月22日~30日的STS-42飞行,在此之后这架航天飞机接受了10个月的地面检  相似文献   

7.
(1)STS-54飞行:奋进号航天飞机的第3次飞行,1月13日发射,飞行6天。主要任务是施放NASA的跟踪与数据中继卫星,进行为建造空间站做准备的第一次舱外活动(已完成)。 (2)STS-55飞行:哥伦比亚号航天飞机的第14次飞行,3月13日发射(经两次推迟后于4月26日升空),飞行9天。主要任务是进行第2次德国专用的“空间实验室”飞行,包括2名德国宇航员的机组人员将在加压实验舱内进行材料与生命科学实验。  相似文献   

8.
综合消息     
欧洲成立哥伦布公司(EuroColumb-us)。股东有阿列尼亚公司(40%)和德国航宇公司(60%) 黑人宇航员最适宜在空间长时间飞行,这是由于黑人有强韧骨骼的遗传特性。在同样飞行条件下,经30天飞行,白人骨损(脱钙)2.5%,黑人则低于1%。世界上已有100架飞机装有航空卫星通信终端机,在这些飞机上的旅客可通过国际海事卫星与地面通电话。意大利阿列尼亚公司出售第45座地球站,该站装在加拉帕戈斯群岛上,配有13米口径的抛物面天线(拥有60条活路和1个电  相似文献   

9.
<正>从当前我国卫星技术的发展来看,低轨遥感卫星的设计寿命要求逐渐从2~3年提高到5~8年,遭受空间碎片撞击的概率大幅提高,空间微小碎片对卫星的累积撞击效应的危害性研究也日益受到重视。俄罗斯的和平号空间站在轨飞行15年,其70%的外体遭受到腐蚀,坚固程度下降了约60%,美国的"长期暴露装置"(LDEF)在轨运行了5.75年后回收,地面检测到的撞击坑达34000个,其中85%以上是微小碎片撞击形成的。现对卫星遭受空间碎片的影响及其危害进行分析,为长寿命低轨遥感卫星的空间碎片防护设计提供思路,提高卫星在轨运行的可靠性。  相似文献   

10.
正NASA网站报道,NASA双胞胎实验研究人员在2018年1月22日举行的NASA人类研究计划(HRP)研讨会上发布了针对航天员Scott在空间飞行前中后身体各系统,以及作为地面对照组的其双胞胎兄弟Mark的持续两年的10项实验的详细研究结果。这些研究结果初步揭示了空间飞行对人体主要系统的  相似文献   

11.
Space flight experiments on Chinese silkworm (Bombyx mori L.) were conducted on board the Russian 10th Biosatellite for 12 days. The samples included silkworm eggs, larvae, cocoons, pupae and moths. The processes of spinning, cocooning, mating, oviposition, larval hatching, pupation and moth emergence all completed well in space. The following effects of space flight on silkworm development were observed: The times of hatching and oviposition in the flight group were 2 to 3 days earlier than in the control group; the hatching rate of diapause eggs during space flight seemed higher than that of the control group; the life span of 2 of the 7 varieties flown was shortened; genetical variations appeared in 3 varieties. The results showed that the embryonic stage was probably the period most sensitive to the space flight environment.  相似文献   

12.
Cauliflower and sprout broccoli are widely planted vegetables particularly in Fujian Province, China. To study the mutation in these two types of vegetables induced from spaceflight, we flew the seeds on the 20th Chinese recoverable satellite which orbited the Earth for 18 days. After returning to the Earth, the cauliflower seeds were planted for two generations and the sprout broccoli seeds for one generation at the Xiamen Agriculture Research Institute. Of the 12 cauliflowers planted for the first generation, two showed significant phenotypical changes in both the size of the plant and the weight of the flower head. In addition, most of the space flown plants were found to be resistant to the black rot attack in the field. Cauliflowers planted for the second generation from the seeds in one of the two plants that displayed phenotypical changes in the first generation showed similar mutations. For the first generation of sprout broccoli, the rate of emergence from the flown seeds was lower than that of the control by 30%. No significant changes in the phenotype between the sprout broccolis planted from the flown seeds and the control were observed except one of the mutated sprout broccolis showed a change in the appearance in the lesser bud of the chief flower head. Results of the study demonstrated that DNA damages in some of the genes may have occurred in the seeds flown in space, and some of the changes in the genes may have inherited from the first to the second generation. The improved resistance to the black rot attack and increased size of the flower head are apparently beneficial.  相似文献   

13.
A system has been developed to enable the normal development of aborted very early uterine avian embryos, outside the female's uterus. The shell-less aborted egg was put into a foster shell of a sister egg, previously laid by the same female. The empty space between the shell and aborted egg was filled with artificial uterine fluid. The reconstructed eggs were incubated at 42 degrees C for 30 hours in a vertical position. The atmosphere contained a high concentration of CO2 (8-10%). At the termination of the 30 h the eggs were transferred to incubation at 37 degrees C in normal atmospheric conditions. Normal development has been recorded for a certain percentage of eggs incubated up to 12 days. In other cases abnormalities, arrested development or development of extraembryonic membranes only, without a sign of an embryonic axis, have been observed. The three important conclusions from the above experiments were: 1. It is possible to develop a closed, self-contained system, disconnected from the female's body, that would support the development of early uterine embryos. 2. The incidence of embryo-less extraembryonic membranes in such a system, is correlated with the degree of detachment of the "yolk" from the outer envelopes. 3. Such a system can be further developed into an experiment suited for microgravity conditions which will be an alternative to an experiment with live birds. The experiment will be aimed at testing the importance of gravity in changing the radially symmetrical avian blastoderm into a bilaterally symmetrical blastoderm.  相似文献   

14.
Transient effects of microgravity on early embryos of Xenopus laevis.   总被引:1,自引:0,他引:1  
In order to study the role of gravity on the early development of the clawed toad Xenopus laevis, we performed an experiment on the Maser-6 sounding rocket launched from Kiruna (Sweden) on 4 Nov 1993. The aim was to find out whether a short period of microgravity during fertilization and the first few minutes of development does indeed result in abnormal axis formation as was suggested by a pilot experiment on the Maser 3 in 1989. On the Maser 6 we used two new technical additions in the Fokker CIS unit, viz. a 1-g control centrifuge and a video recording unit which both worked successfully. The 1-g control centrifuge was used to discriminate between the influences of flight perturbations and microgravity. After fertilization shortly before launch, one of the first indications of successful egg activation, the cortical contraction, was registered in microgravity and on earth. Analysis of the video tapes revealed that the cortical contraction in microgravity starts earlier than at 1 g on earth. After recovery of the eggs fertilized in microgravity and culture of the embryos on earth, the morphology of the blastocoel has some consistent differences from blastulae from eggs fertilized in the 1-g centrifuge of the rocket. However from the gastrula stage onward, the microgravity embryos apparently recover and resume normal development: the XBra gene is normally expressed, and histological examination shows normal axis formation.  相似文献   

15.
During the TEXUS-17 flight (April/May 1988) eggs of a higher organism, the anuran amphibian Xenopus laevis, have for the first time been successfully fertilized under microgravity on a Sounding Rocket. This result also implies that Life Sciences Experiments of Short Duration can be carried out on Sounding Rockets. The latter can therefore function as additional carriers for such experiments. Histological sections of the experimental material demonstrated the penetration of sperm into eggs, while SEM analysis revealed the differentiation of characteristic egg surface structures. Our TEXUS-17 experiment convincingly shows that the modified automatic experiment container, originally designed for experimental BR 52NL on the D1-mission, now functions flawlessly. Eight containers were flown in an airtight, well-isolated box (TEM 06-15), and a similar set was activated on Earth, two hours later. The analysis of the biological material is in progress.  相似文献   

16.
Intensity of osteoclastic resorption and calcium content were investigated in intact limb bones of the newts flown on board of a biosatellite Cosmos-2229 after amputation of their forelimbs and tail. Using X-ray microanalysis it was shown an increase in calcium content in the bones on 20th day after operation. Histological study revealed an activation of osteoclastic resorption on endosteal surface of long bones. The newts exposed after surgery on a biosatellite had the same level of bone mineralisation as operated ground control ones, but the increase in number of polynuclear osteoclasts was lower.  相似文献   

17.
Japanese tree frogs (Hyla japonica) were flown to the space station MIR and spent eight days in orbit during December, 1990. Under microgravity, their postures and behaviors were observed and recorded. On the MIR, floating frogs stretched four legs out, bent their bodies backward and expanded their abdomens. Frogs on a surface often bent their neck backward and walked backwards. This behavior was observed on parabolic flights and resembles the retching behavior of sick frogs on land--a possible indicator of motion sickness. Observations on MIR were carried out twice to investigate the frog's adaptation to space. The frequency of failure in landing after a jump decreased in the second observation period. After the frogs returned to earth, readaptation processes were observed. The frogs behaved normally as early as 2.5 hours after landing.  相似文献   

18.
The Ballooncraft Support Systems were developed by NASA Wallops Flight Facility for use on ULDB class balloon missions. The support systems have now flown two missions supporting the Cosmic Rays Energetics and Mass (CREAM) experiment. The first, CREAM I, flown in December 2004, was for a record breaking 41 days, 21 h, and the second flight flown in December 2005, was for 28 days, 9 h. These support systems provide CREAM with power, telecommunications, command, and data handling including flight computers, mechanical structures, thermal management, and attitude control to help ensure a successful scientific mission. This paper addresses the performance and success of these support systems over the two missions.  相似文献   

19.
The aim of the experiment "Seeds" on the Sowjetic satellite Biokosmos 9 was the observation of mutagenic effects caused at special loci of seeds of Arabidopsis thaliana and assigned to particles of the Cosmic radiation. Two types of exposure units were flown: A low-shielding unit Type I, mounted at the surface of the satellite (1.4 g/cm2 shielding) and, for comparison, an identical item inside (16 g/cm2 shielding), using nuclear emulsion as track detectors. A Type II unit, flown inside (18g/cm2 shielding) was mounted with AgCl track detectors. The layout will be briefly described. A first set of dosimetric data from the physical evaluation of the experiment will be presented. The subdivision into charge- and LET-groups shows a rather high contribution of the intermediate LET-group (350-1000 MeV/cm) due to medium heavy particles (Z = 6-10) and to enders of light (p, alpha) particles.  相似文献   

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