Life In Space: An Introduction To Space Life Sciences And The International Space Station

The impact of the space environment upon living organisms is profound. Its effects range from alterations in sub-cellular processes to changes in the structure and function of whole organ systems. As the number of astronaut and cosmonaut crews flown in space has grown, so to has our understanding of the effects of the space environment upon biological systems. There are many parallels between the physiology of space flight and terrestrial disease processes, and the response of astronaut crews themselves to long-duration space deployment is therefore of central interest. In the next 15 years the International Space Station (ISS) will serve as a permanently manned dedicated life and physical sciences platform for the further investigation of these phenomena. The European Space Agency's Columbus module will hold the bulk of the ISS life science capability and, in combination with NASA's Human Research Facility (HRF) will accommodate the rack mounted experimental apparatus. The programme of experimentation will include efforts in fundamental biology, human physiology, behavioural science and space biomedical research. In the four decades since Yuri Gagarin first orbited the Earth, space life science has emerged as a field of study in its own right. The ISS takes us into the next era of human space exploration, and it is hoped that its programme of research will yield new insights, novel therapeutic interventions, and improved biotechnology for terrestrial application. This revised version was published online in July 2006 with corrections to the Cover Date.     

Gravity and aeromagnetic constraints on the structure of the Woods Mountains volcanic center, southeastern California

 The Woods Mountain volcanic center is a well-exposed, mildly alkaline volcanic center that formed during the Miocene in southeastern California. Detailed geologic mapping and geochemical studies have distinguished three major volcanic phases: precaldera, caldera forming, and postcaldera. Geologic mapping indicates that caldera formation occurred incrementally during eruptions of three large ignimbrites and continued into a period of voluminous intracaldera lava-flow eruptions. Rhyolitic ignimbrites and lava flows within the caldera are associated with large amplitude, circular gravity, and magnetic minima that are among the most prominent gravity and magnetic anomalies in southeastern California. Analysis of a Bouguer gravity anomaly map, reduced-to-the-pole magnetic intensity map, and three-dimensional gravity and magnetic models indicates that there is a single, funnel- to bowl-shaped caldera approximately 4 km thick and approximately 10 km wide at the surface. This model is consistent with other siliceous, pyroclastic-filled calderas on continental crust, except that most siliceous volcanic centers associated with more than one eruption are characterized by more than one caldera. Received: 20 December 1997 / Accepted: 15 October 1998     

Meteoroid streams at Mars: possibilities and implications

In order to assess the possibility of meteoroid streams detectable from the surface of Mars as meteor showers we have derived minimum distances and associated velocities for a large sample of small body orbits relative to the orbits of Mars and the Earth. The population ratio for objects approaching to within 0.2 AU of these two planets is found to be approximately 2:1. The smaller relative velocities in the case of Mars appears to be the main impediment to the detection of meteors in the upper atmosphere of that planet. We identify five bodies, including the unusual object (5335) Damocles and periodic comet 1P/Halley, with relative orbital parameters most suitable to produce prominent meteor showers. We identify specific epochs at which showers related to these bodies are expected to occur. An overview of possible detection methods taking into account the unique characteristics of the Martian environment is presented. We pay particular attention on the effects of such streams on the dust rings believed to be present around Mars.     

Diagenetic mineral development within the Upper Jurassic Haynesville-Bossier Shale,USA

Despite recent advances, diagenetic processes in fine-grained sediments are still relatively poorly understood. Key questions still to be resolved include the types of diagenetic minerals present in mudstones and the extent of element mobility in these low permeability systems. This study utilizes data from the Haynesville-Bossier Shale, USA, to analyze lithologies, discriminate authigenic phases and identify mobile elements during diagenesis. It has implications for understanding how authigenic minerals develop and the sources of those authigenic minerals in fine-grained sediments. On the basis of grain-size and mineralogy five lithologies are designated: (i) silica-rich argillaceous mudstones; (ii) argillaceous siliceous mudstones; (iii) mixed siliceous mudstones; (iv) mixed mudstones; and (v) authigenically-dominated mudstones. The diagenetic development of the Haynesville-Bossier Shale can be divided into early and late diagenesis. Ferroan and non-ferroan dolomite, framboidal pyrite and bioclast pore-filling kaolinite and calcite grain replacements and cements all formed during early diagenesis. Late diagenetic mineral phases include illite formed by the illitization of smectite, replacive and displacive chlorite, calcite-replacive albite, quartz-replacive calcite and replacive and/or displacive quartz. The presence of extensive late diagenetic mineral precipitates indicates that there was a degree of element mobility on at least the local scale. Aluminium present in albite is most likely to have resulted from the illitization of smectite. Quartz overgrowths probably resulted from illitization and the pressure dissolution at quartz silt grain boundaries. Externally, hydrothermal fluids resulting from regional-scale igneous activity appear to have played a role in the formation of chlorite and possibly albite. The work indicates that extensive mineral development and element mobility occurred during late diagenesis.     

IFSAR-DEM在岩溶洼地探测中的应用——以薄荷省旁劳市沉降灾害评估为例

岩溶研究中,通常会使用高分辨率卫星图像和地理空间数据识别、描绘岩溶发育及相关地质灾害发生的地貌特征。本文旨在利用ArcGIS10.0确定干涉合成孔径雷达数字高程模型（IFSAR-DEM）识别、量化和描述岩溶洼地。这种半自动岩溶洼地/天坑探测方法采用水流模拟法,并结合（1）流域划分;（2）下沉填充法提取洼地特征;（3）下沉深度测量及分类;（4）使用2013年至2014年谷歌高光谱卫星图像和数字地形模型对探测到的岩溶洼地进行验证。该方法已在薄荷省旁劳市进行的评估中进行了预测试。使用国家测绘资源信息局（菲律宾）1991年的1:50 000比例尺地形图进行的初步封闭洼地分析,发现旁劳岛有15个天坑。利用5米高分辨率IFSAR-DEM,共探测到820个天坑,其中424个根据详细的地面实况进行了描绘,以验证了岩溶洼地的存在。地表实况包含天坑大小、形状和深度等基本形态测量分析以消除误报数据。阈值设定为沉降深度大于1米,孔径大于10米,从而最大程度精确区分实际的天坑。这种基于GIS的工具有助于生成高分辨率岩溶塌陷易发区图,继而指导当地规划者、工程师及决策者进行开发规划和土地利用。      

Statistical estimation of extreme ocean environments: The requirement for modelling directionality and other covariate effects

With increasing availability of good directional data, provision of directional estimates of extreme significant wave heights, in addition to the omni-directional estimates, is more common. However, interpretation of directional together with omni-directional design criteria is subject to inconsistency, even in design guidelines. In particular, omni-directional criteria are usually estimated ignoring directional effects. In this article, for data which exhibit directional effects, we show that a directional extreme value model generally explains the observed variation significantly better than a model which ignores directionality, and that omni-directional criteria developed from a directional model are different from those generated when directionality is not accounted for. We also show that omni-directional criteria derived from a directional model are more accurate and should be preferred in general over those based on models which ignore directional effects. We recommend use of directional extreme value models for estimation of both directional and omni-directional design criteria in future, when good directional data are available. If effects of other covariates (e.g. time or space) are suspected, we similarly recommend use of extreme value models which adequately capture sources of covariate variability for all design analysis.     

Photosynthetic community responses to upwelling in mesoscale eddies in the subtropical North Atlantic and Pacific Oceans

In this paper we summarise the photo-physiological responses of phytoplankton to upwelling of macronutrients in mesoscale eddies in the subtropical North Atlantic (EDDIES project, Sargasso Sea) and subtropical North Pacific (E-FLUX project, Hawaii). The observations, obtained on two sets of cruises over 2 years, occupied six cyclonic eddies and two mode-water eddies. The photosynthetic physiological parameters were measured using a bench-top fluorescence induction and relaxation (FIRe) system and a submersible in situ fast repetition rate fluorometer (FRRF) deployed on an undulating towed vehicle. Both of these instruments were used to provide highly sensitive and well-resolved data on community responses. The responses are dependent on both the type of eddy and its stage of development. Our results indicate that, while cyclonic eddies in the Atlantic and Pacific can increase primary photosynthetic production early in their development, mode-water eddies in the subtropical North Atlantic can support patchy blooms of large diatoms for long periods of time (more than 3 months).     

A Causality-guided Statistical Approach for Modeling Extreme Mei-yu Rainfall Based on Known Large-scale Modes——A Pilot Study

Extreme Mei-yu rainfall(MYR) can cause catastrophic impacts to the economic development and societal welfare in China. While significant improvements have been made in climate models, they often struggle to simulate local-to-regional extreme rainfall(e.g., MYR). Yet, large-scale climate modes(LSCMs) are relatively well represented in climate models.Since there exists a close relationship between MYR and various LSCMs, it might be possible to develop causality-guided statistical models for MYR pr...