京津风沙源区沙障固沙技术评价指标体系构建

由于构成材料、规格形状以及自然风向和地貌形态的多样性,不同沙障固沙技术的固沙效果有较大差异,如何科学客观的筛选沙障固沙技术,是保证沙障固沙技术长期稳定发挥其最大作用的重要基础。针对京津风沙源区沙障固沙技术效果评价问题,建立了沙障固沙技术评价的方法体系,明确了沙障固沙技术评价指标集、评价指标权重以及沙障固沙技术评价面临的问题。在沙障固沙技术与地区自然条件、经济发展水平相协调的前提下,基于文献频次法和层次分析法(analytic hierarchy process,AHP)从技术成熟度、技术应用难度、技术相宜性、技术效益、技术推广潜力5个方面共筛选出1项判断性指标、4项准则性指标、14项二级指标和25项三级指标指标,构建沙障固沙技术评价指标体系。该指标体系以技术效益为主导,兼顾功能性和应用性综合评价,从而对京津风沙源区沙障固沙技术进行全面评价。     

Afterword to "Cruelty, Suffering, Imagination: The Lessons of J. M. Coetzee": Anthropologists as Public Intellectuals, Again

Anthropologists' interest in literature and novelists' interest in cultural criticism converge in J. M. Coetzee's Elizabeth Costello (2003) and in these four "In Focus" responses to the book. Recent discussions of ethnographic writing seem to have prepared anthropologists for the generic innovations of the novel, leaving us free to take up the pressing moral problems that Coetzee rehearses. To speak to a broad public about such issues remains a challenge for anthropologists, who would do well to study the ways novelists have found to make their political voices heard.     

The significance of mating processes for the genetics and for the formation of resting eggs in monogonont rotifers

Crossbreeding experiments with three geographically distinct strains (E, S, and L) of the rotifer Brachionus plicatilis have been carried out in an attempt to elucidate the apparent male sterility of strain L, which is unable to produce resting eggs.The 9 crossing possibilities of the three strains have been investigated in 27 experiments. The results refute the concept of male sterility. L-males copulate successfully with mictic as well as with amictic females of strains E and S. Fertilized amictic E and S females produce defective resting eggs, which have only one thin shell and, which disintegrate after deposition. L-females cannot, as a rule, be fertilized. Moreover, crosses between strain E and S are succesful only in one direction; the reciprocal crosses failed.To explain the present results a hypothesis is suggested that the thickness of the body wall of newborn females differs in the three strains, and between mictic and amictic individuals. A sequence of gradually increasing body wall thickness of all types of females involved, together with a comparably increasing penetration ability of the males of strain E, S, and L explains the success or failure of all crosses, including the unilateral cross E × S.     

Mammalian hybrid zones: a review

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A visual patient feedback device using optical surface measurement for the cooperative management of setup and body dynamics during radiotherapy

In this technical note we describe a real-time visual feedback device for use during radiotherapy treatment. The device displays a patient's live pose and position, relative to a reference, to them, helping them to control and maintain their motion. The device uses an optical sensor system developed at The Christie NHS Foundation Trust that is capable of real-time performance of up to 24 unique wide-area body surface measurements per second. The feedback device has integrated audio and three intuitive visualisation modes designed to show different levels of detail with varying degrees of complexity: a ‘2D traffic-light display’, ‘3D flexing lamina display’ and ‘3D colour-mapped surface display’. The performance characteristics of the system were measured, with the frame rate, throughput and latency of the feedback device being 22.4 fps, 47.0 Mbps, 109.8 ms, and 13.7 fps, 86.4 Mbps, 119.1 ms for single and three-channel modes respectively. We additionally present a novel fast method for calculating the vertical displacement map of two 3D surfaces suitable for live, real time display and evaluate its precision with respect to other methodologies.     

Effects of climate‐induced increases in summer drought on riparian plant species: a meta‐analysis

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研究生神经生物学教学创新模式探索与实践

结合神经生物学课程的特点与研究生培养要求,提出了将神经生物学理论与方法知识贯穿到多媒体课程学习、文献讨论、学术交流、科研活动等实践环节中,注重培养研究生对神经生物学理论和研究实践的兴趣,强化科研能力创新人才的培养。     

The contribution of scientific information to the conservation and management of freshwater biodiversity in tropical Asia

Tropical Asia (i.e. the Oriental biogeographic region) is the most densely populated and degraded region on Earth with the highest deforestation rates in the tropics. Flow regulation is a significant threat to riverine biodiversity in the region, and its impacts are combined with overharvesting, pollution and other sources of habitat degradation. In addition to these immediate threats, the potential impacts of exotic species and climate change are difficult to predict. Uncertainty about impact effects arises also from the fact that knowledge of the rich freshwater biodiversity of tropical Asia is incomplete, and up-to-date national or regional inventories are lacking. In part, this reflects taxonomic constraints, and a limited representation of Asian science in the international limnological and conservation literature. A survey of recent (1992–2001) international journals dealing with freshwater ecology and limnology in general, on one hand, and conservation biology on the other, reveal that the representation of scientists based in tropical Asia was extremely low. Scientists from tropical Asia authored fewer than 2% of more than 4500 papers dealing with freshwater biology; 57% of them were published in Hydrobiologia. Less than 0.1% of freshwater biology papers dealt with the conservation of biodiversity in tropical Asian fresh waters. The representation of Asian freshwater science in the conservation biology literature was also poor; 0.6% of 1880 papers surveyed. Such limited dissemination of information reflects a variety of constraints (e.g. manpower, funding, language, and entrenched attitudes), arising from sources both within and outside the region. Even the data that are published are not effectively deployed toward conservation ends. Awareness of some of the more egregious examples of overharvesting (e.g. of river turtles) in the region has increased, but strategies for the protection of riverine biodiversity remain underdeveloped. Where legislation to protect water resources has been put in place, it has been directed towards enhancing human use of water – not biodiversity conservation – and enforcement is weak. Exceptionally, the Chinese government has produced national `Red Data Books' for endangered freshwater vertebrates, and legislation aimed at protecting species at risk, particularly from overharvesting, are in place. Huge obstacles remain, especially in the management of rivers crossing international boundaries. The Mekong River Commission (MRC) provides an example of a model for an international drainage basin that has made significant progress in establishing appropriate structures and mechanisms for sustainable development in a challenging political landscape. Not all of the Mekong riparian states participate in the MRC, and this will be essential for sustainable management. However, even within national borders, local interests can override drainage-basin perspectives. In many places in Asia, preservation of near-pristine freshwater environments is not a realistic option. Sustaining human livelihoods is an over-riding concern, and recognition of this fact must be built in to biodiversity conservation efforts. This has special implications for the management of exotic species, as the example of fish introductions to the Sepik River in Papua New Guinea shows. Notwithstanding the various factors that constrain publication by scientists in tropical Asia, we must recognise that poor dissemination research results will have consequences for the long-term preservation of the habitats and biodiversity that we study. A change in research strategy that establishes priorities, recognises the inevitability of trade-offs, and includes greater emphasis on engagement and partnerships – as in the MRC – is mandated.