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Astronauts face numerous health challenges during long-duration space missions, including diminished immunity, bone loss and increased risk of radiation-induced carcinogenesis. Changes in the intestinal flora of astronauts may contribute to these problems. Soy-based fermented food products could provide a nutritional strategy to help alleviate these challenges by incorporating beneficial lactic acid bacteria, while reaping the benefits of soy isoflavones. We carried out strain selection for the development of soy ferments, selecting strains of lactic acid bacteria showing the most effective growth and fermentation ability in soy milk (Streptococcus thermophilus ST5, Bifidobacterium longum R0175 and Lactobacillus helveticus R0052). Immunomodulatory bioactivity of selected ferments was assessed using an in vitro challenge system with human intestinal epithelial and macrophage cell lines, and selected ferments show the ability to down-regulate production of the pro-inflammatory cytokine interleukin-8 following challenge with tumour necrosis factor-alpha. The impact of fermentation on vitamin B1 and B6 levels and on isoflavone biotransformation to agluconic forms was also assessed, with strain variation-dependent biotransformation ability detected. Overall this suggests that probiotic bacteria can be successfully utilized to develop soy-based fermented products targeted against health problems associated with long-term space travel.  相似文献   
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Messaging to extraterrestrial intelligence (METI) is a branch of study concerned with constructing and broadcasting a message toward habitable planets. Since the Arecibo message of 1974, the handful of METI broadcasts have increased in content and complexity, but the lack of an established protocol has produced unorganized or cryptic messages that could be difficult to interpret. Here we outline the development of a self-consistent protocol for messaging to extraterrestrial intelligence that provides constraints and guidelines for the construction of a message in order to maximize the probability that the message effectively communicates. A METI protocol considers several factors, including signal encoding, message length, information content, anthropocentrism, transmission method, and transmission periodicity. Once developed, the protocol will be released for testing on different human groups worldwide and across cultural boundaries. An effective message to extraterrestrials should at least be understandable by humans; releasing the protocol for testing will allow us to improve the protocol and develop potential messages. Through an interactive website, users across the world will be able to create and exchange messages that follow the protocol in order to discover the types of message better suited to cross-cultural communication. The development of a METI protocol will serve to improve the quality of messages to extraterrestrials, foster international collaboration, and extend astrobiology outreach to the public.  相似文献   
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钛合金扩散连接界面完整性超声定量评估   总被引:3,自引:0,他引:3  
利用高分辨率超声扫描显微成像检测技术对钛合金扩散连接界面的微缺陷分布进行研究 ,从而得到有关扩散界面微观完整性的定量信息 ,给出了钛合金扩散连接界面的超声扫描成像检测的典型试验结果  相似文献   
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An important goal of New Millennium is to research new methods of performing spacecraft and mission design. We have completed the first phase of our effort on how to make design tools such as analysis programs more available. We are now embarking with Stanford University on discovering methods to allow more project history and knowledge to be automatically captured and reused and with Ames Research Center on how to use virtual reality to enhance the visualization of new missions before any hardware exists. We are also trying to capture the design process in an electronic form so that computer aided optimization may lead to a vastly greater search of the possible designs which meet the design requirements.  相似文献   
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We describe a novel approach for determining the timing of the solar cycle and tracking its evolution relative to other cycles. This method also has predictive capability for forecasting the cycle “onset.” Based on current trends, we expect that Cycle 23 will be about 1 year longer than the previous two cycles.  相似文献   
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High spectral resolution X-ray instruments on powerful X-ray satellites (e.g. Chandra, XMM-Newton) pointed through dust and gas at bright black holes and neutron stars can be used to study dust and intervening material in unique ways. With the new subfield of Condensed Matter Astrophysics as its goal, I will discuss current efforts to combine techniques and knowledge from condensed matter physics and astrophysics to determine the species-specific quantity and composition of interstellar gas and dust in the ISM and ionized environments. Prospects for improving on this work in future X-ray missions with higher throughput and spectral resolution are also presented in the context of spectral resolution goals for gratings and calorimeters.  相似文献   
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Abstract

We investigated the influence of environmental axes in a baseball field. In Experiment 1, participants walked either a path in the prototypical orientation (home plate to second base) or one which was rotated 225°. Recall for object locations was best when participants imagined themselves aligned with axes salient from the experienced orientation. In Experiment 2, when learning was through a route text, there was less of an influence of environmental axes. In Experiment 3, when participants walked both paths, memories were good for the atypical orientation, suggesting that task-specific spatial cues can be more influential than a prior conceptual north.  相似文献   
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