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国外铀金地质 1991年第3期7卷 16-24页

作者： george A.parks Demetrius C.Pohl 张家富

在温变为100—300℃,压力(P_(H2))为50MPa,pH的计算值为1-10的条件下测量了UO_2在HCl、NaOH或LiOH水溶液中的溶解度。氟化物的污染对pH值为2—4的测量结果没有影响.在pH值约为3时观测到的溶解度的最大值可能是可靠的。在pH4时,实验结果... 详细信息

在温变为100—300℃,压力(P_(H2))为50MPa,pH的计算值为1-10的条件下测量了UO_2在HCl、NaOH或LiOH水溶液中的溶解度。氟化物的污染对pH值为2—4的测量结果没有影响.在pH值约为3时观测到的溶解度的最大值可能是可靠的。在pHkolaeva和Pirozhkov(1978)及Bruno等(1986)的测量结果是一致的,并且与Wolery(1983)为非晶质阳晶质UO_2选择的溶解度完全相符。溶解度与pH的相关性说明溶液中以UOH^(3+)为主。在碱性介质中,在各种温度下UO_2的溶解度明显低于以前所作的各种测量和估算结果,这说明U(OH)_5^-络合物极不稳定或不存在.它在pH4时,实验结果表明温度和pH的相关性没有统计学上的意义。这说明溶液中以U(OH)_4(aq)为主,其溶解反应: UO_2+2H_2O=U(OH)_4(aq)当温度为100—300℃时,该反应: lag(k_(s,4)=-9.47±0.

关键词：铀矿矿床热液可溶性晶质

用斯波特卫星MSS和5号陆地卫星TM资料对有复杂光谱和空间特征的宾夕法尼亚中部露天采煤区的遥感解译——两种高分辨率遥感资料的比较

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自然资源遥感 1988年第2期 46-53页

作者： Nancy F.parks Gary W.Petersen george M.Baumer 张耀魁宾夕法尼亚州立大学农艺系宾夕法尼亚州立大学农艺系宾夕法尼亚州立大学地球资源遥感处

为了清查宾夕法尼亚中部潮湿的采煤区植被生长和采场恢复情况,我们把斯波特卫星MSS资料和5号陆地卫星的TM资料作了比较。这两种资料分别是1983年7月8日和1984年4月12日接收的。我们还搜集了在同一地区4号陆地卫星于1983年7月7日接收的MS... 详细信息

为了清查宾夕法尼亚中部潮湿的采煤区植被生长和采场恢复情况,我们把斯波特卫星MSS资料和5号陆地卫星的TM资料作了比较。这两种资料分别是1983年7月8日和1984年4月12日接收的。我们还搜集了在同一地区4号陆地卫星于1983年7月7日接收的MSS资料。航空像片和先期搜集的地面实况资料也为此项研究工作提供了方便。图像分析和数字化技术着重突出了植被分类和采区破坏程度的分类。用高分辨率遥感资料的最大或然率分类将各种植被种类、年龄和覆盖密度划分成92～115％的精度。此项研究证明,在建立宾夕法尼亚露天采矿管理人员在土地调查时采用的基础性综合资料方面,高分辨率遥感资料具有很大的潜力。

关键词：陆地卫星斯波特卫星矿渣宾夕法尼亚美国高分辨率高分辨力遥感资料空间特征 MSS TM

Microglia activation,classification and microglia-mediated neuroinflammatory modulators in subarachnoid hemorrhage

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Neural Regeneration Research 2022年第7期17卷 1404-1411页

作者： Junfan Chen Zhiyuan Vera Zheng Gang Lu Wai Yee Chan Yisen Zhang george kwok Chu Wong Division of Neurosurgery Department of SurgeryThe Chinese University of Hong KongHong Kong Special Administrative RegionChina Department of Neurosurgery Hainan Branch of Chinese People’s Liberation Army General HospitalSanyaHainan ProvinceChina CUHk-SDU Joint Laboratory on Reproductive Genetics School of Biomedical Sciencesthe Chinese University of Hong KongHong Kong Special Administrative RegionChina Bioinformatics Unit SDIVF R&D CentreHong Kong Science and Technology ParksHong Kong Special Administrative RegionChina Department of Interventional Neuroradiology Beijing Neurosurgical InstituteBeijing Tiantan HospitalCapital Medical UniversityBeijingChina

Subarachnoid hemorrhage is a devastating disease with significant mortality and morbidity,despite advances in treating cerebral *** has been recent progress in the intensive care management and monitoring of patients with subarachnoid hemorrhage,but the results remain ***,the resident immune cells of the brain,are increasingly recognized as playing a significant role in neurological diseases,including subarachnoid *** early brain injury following subarachnoid hemorrhage,microglial activation and neuroinflammation have been implicated in the development of disease complications and *** understand the disease processes following subarachnoid hemorrhage,it is important to focus on the modulators of microglial activation and the pro-inflammatory/anti-inflammatory cytokines and *** this review,we summarize research on the modulators of microglia-mediated inflammation in subarachnoid hemorrhage,including transcriptome changes and the neuroinflammatory signaling *** also describe the latest developments in single-cell transcriptomics for microglia and summarize advances that have been made in the transcriptome-based classification of microglia and the implications for microglial activation and neuroinflammation.

关键词： activation inflammation microglia modulator neuroinflammation sequencing signal pathway single-cell analysis stroke subarachnoid hemorrhage treatment

Nitric Oxide Is Required for Homeostasis of Oxygen and Reactive Oxygen Species in Barley Roots under Aerobic Conditions

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Molecular Plant 2014年第4期7卷 747-750页

作者： kapuganti J. Gupta kim H. Hebelstrup Nicholas J. kruger R. george Ratcliffe Department of Plant Sciences University of OxfordSouth Parks RoadOxfordOX1 3RBUK Department of Molecular Biology and Genetics Aarhus UniversityForsogsvej 14200 SlagelseDenmark

Oxygen, the terminal electron acceptor for mitochondrial electron transport, is vital for plants because of its role in the production of ATP by oxidative phosphorylation. While photosynthetic oxygen production contributes to the oxygen supply in leaves, reducing the risk of oxygen limitation of mitochondrial metabolism under most conditions, root tissues often suffer oxygen deprivation during normal development due to the lack of an endogenous supply and isolation from atmospheric oxygen.

关键词： MITOCHONDRIA NO

Comparative sensitivity to environmental variation and human disturbance of Asian tapirs (Tapirus indicus) and other wild ungulates in Thailand

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Integrative Zoology 2012年第4期7卷 389-399页

作者： Antony J.LYNAM Naruemon TANTIPISANUH Wanlop CHUTIPONG Dusit NGOPRASERT Megan C.BAkER Passanan CUTTER george GALE Shumpei kITAMURA Robert STEINMETZ Ronglarp SUkMASUANG Somying THUNHIkORN Global Conservation Program Wildlife Conservation Society(WCS)BronxNYUSA IUCN/SSC Tapir Specialist Group BangkokThailand Conservation Ecology Program King Mongkut’s University of Technology ThonburiBangkokThailand Center for Species Survival Smithsonian Conservation Biology InstituteFront RoyalVirginiaUSA Conservation Biology Program University of MinnesotaSt.PaulMinnesotaUSA Museum of Nature and Human Activities SandaJapan WWF Thailand BangkokThailand Department of Forest Biology Kasetsart UniversityBangkokThailand Wildlife Research Division Department of National ParksWildlife and Plants ConservationBangkokThailand

Southeast Asia’s tropical forests suffer the highest rates of deforestation and disturbance of any on Earth,with poorly understood impacts on native *** tapirs(Tapirus indicus)are among the least studied of the large mammals in these *** records from 9 camera trap surveys in 7 of the largest(>1000 km2)pro-tected area complexes,we assessed the influence of environmental variation and human-induced disturbance on tapir *** were detected at 13%of locations sampled,significantly associated with evergreen for-est(Pk traffic periods in *** populations in Thailand may be more stable than in other parts of their global range because rates of forest loss have decreased>40%over the past 20 *** recommend surveys to fill gaps in the understanding of the status in lesser-known protected areas,research to better understand the fine-scale environmental influences on behavior and habitats of tapirs,and other forest un-gulates,and continued legal status for tapirs in the highest category of protection.

关键词： Asian tapir camera traps conservation logistic regression ungulates

Increased connectivity of hiPSC-derived neural networks in multiphase granular hydrogel scaffolds

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Bioactive Materials 2022年第3期7卷 358-372页

作者： Chia-Chen Hsu Julian H.george Sharlayne Waller Cyril Besnard David A Nagel Eric J Hill Michael D.Coleman Alexander M.korsunsky Zhanfeng Cui Hua Ye Institute of Biomedical Engineering Department of Engineering ScienceUniversity of OxfordOX37DQUK MBLEM Department of Engineering ScienceUniversity of OxfordParks RoadOxfordOX13PJUK School of Biosciences College of Health and Life SciencesAston UniversityBirminghamB47ETUK Translational Medicine Research Group Aston Medical SchoolCollege of Health and Life SciencesAston UniversityBirminghamB47ETUK

To reflect human development,it is critical to create a substrate that can support long-term cell survival,differentiation,and *** are promising materials for 3D ***,a bulk structure consisting of dense polymer networks often leads to suboptimal microenvironments that impedes nutrient exchange and cell-to-cell ***,granular hydrogel-based scaffolds were used to support 3D human induced pluripotent stem cell(hiPSC)-derived neural networks.A custom designed 3D printed toolset was developed to extrude hyaluronic acid hydrogel through a porous nylon fabric to generate hydrogel *** and hydrogel granules were combined using a weaker secondary gelation step,forming self-supporting cell laden *** three and seven days,granular scaffolds supported higher cell viability compared to bulk hydrogels,whereas granular scaffolds supported more neurite bearing cells and longer neurite extensions(65.52±11.59μm)after seven days compared to bulk hydrogels(22.90±4.70μm).Long-term(three-month)cultures of clinically relevant hiPSC-derived neural cells in granular hydrogels supported well established neuronal and astrocytic colonies and a high level of neurite extension both inside and beyond the *** approach is significant as it provides a simple,rapid and efficient way to achieve a tissue-relevant granular structure within hydrogel cultures.

关键词： Microgel Hydrogel Hyaluronan iPSC Neural tissue engineering 3D printing

Canada Thistle (Cirsium arvense) Response to Clipping and Seeding of Competitive Grasses

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American Journal of Plant Sciences 2012年第9期3卷 1252-1259页

作者： Julie knudson Paul Meiman Cynthia Brown george Beck Mark Paschke Edward Redente Department of Bioagricultural Sciences and Pest Management Colorado State University Colorado USA. Department of Forest and Rangeland Stewardship Colorado State University Colorado USA

Chemical restrictions, ecological concerns, liability issues, and public sentiment present challenges to land managers attempting to control highly invasive plants like Canada thistle (Cirsium arvense [L.] Scop.). Although herbicide application can be an effective control strategy, increasing limitations force managers of sensitive environments (e.g., national parks, wildlife refuges, protected water-bodies or waterways) to search for effective control alternatives. A greenhouse study was conducted to test the effectiveness of clipping (to simulate field mowing) and grass seeding as alternatives for Canada thistle control. Two native North American grasses (western wheatgrass [Pascopyrum smithii {Rydb.} A. L?ve] and streambank wheatgrass [Elymus lanceolatus {Scribn. & J.G. Sm.}Gould ssp. lanceolatus]) and one sterile hybrid cross between common wheat (Triticum aestivum L.) and tall wheatgrass (Thinopyrum ponticum [Podp.] Z.W. Liu & R.C. Wang) called RegreenTM were used. The effects of clipping and grass seeding on Canada thistle growth, and the effect of Canada thistle on grass growth, were evaluated using 14 unique treatments applied to potted Canada thistle and grass plants. Clipping inhibited Canada thistle growth (by 60%), while grass seeding had no effect. Presence of Canada thistle inhibited grass growth for all seeding treatments except when RegreenTM and western wheatgrass were seeded together with Canada thistle. Planting multiple species for restoration of Canada thistle-infested sites may be important (RegreenTM + western wheatgrass treatment), and cutting Canada thistle may be useful for reducing its growth in restored areas.

关键词： Invasive Species Mowing Competition Revegetation

“2012国际公共艺术奖”参评作品选(五)

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公共艺术 2012年第6期 106-119页

作者：李丽婴武佳音 george kaye

本期选登的国际公共艺术案例大多为人工构筑物和景观建造。首先,有几个案例都与城市公园相关,体现出不同地域的历史、人文、经济等因素:《光电瀑布》是加拿大第一个具有紫外线雨水处理设施的公园的中心标志;《安阳公共艺术项目》则是将... 详细信息

本期选登的国际公共艺术案例大多为人工构筑物和景观建造。首先,有几个案例都与城市公园相关,体现出不同地域的历史、人文、经济等因素:《光电瀑布》是加拿大第一个具有紫外线雨水处理设施的公园的中心标志;《安阳公共艺术项目》则是将整个城市变成艺术公园的计划,旨在更广阔的语境下扩展公共艺术的概念。其次,坐落在新加坡国家博物馆附近的现代雕塑作品《树》不仅重新诠释神话故事,也被用作人们聚集的场所;《战争与和平及两者之间》采用两尊为人熟知的公共雕塑,赋予观众与地点、地位的标志性符号之间的一种全新关系;《手岛美术馆》和《酒店》则是建筑和雕塑的共同体,两件作品都是没有实用价值的虚构建筑,既传达材料和地点的特定属性,也探索人造环境和人的情感及社会影响的相互关系。《波形》是一幢与大自然为一体的"自由之屋";《通道》则是包括景观设计在内的多方位合作的公共艺术项目。纵观上述案例,虽然与传统意义的雕塑或景观设计有着某种形态上的关联,但其不仅已成为大众交流思想和沟通情感的公共领域,更从作为环境艺术的公共艺术向作为当代艺术的公共艺术转化,极大地拓展了造型艺术的内涵与外延。

关键词：公共艺术艺术家公共空间委托人景观设计博物馆公共雕塑作品新加坡项目

论科学、保护与政府的目的——地球的功能整体性并不是生物多样性的问题

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AMBIO－人类环境杂志 2002年第5期31卷 432-436页

作者： george M.Woodwell 闵庆文 Woods Hole研究中心

20年来,人们一直把保护的目的更多地集中在"生物多样性"的保存上,强调物种丧失所可能造成的损失。所提出的解决办法,也一直是建立公园和保护区,以保护那些"热点地区",特别是在生物多样性程度非常高的热带地区。对于生物多样性的保存,常... 详细信息

20年来,人们一直把保护的目的更多地集中在"生物多样性"的保存上,强调物种丧失所可能造成的损失。所提出的解决办法,也一直是建立公园和保护区,以保护那些"热点地区",特别是在生物多样性程度非常高的热带地区。对于生物多样性的保存,常常还包括建立保护区之间的联系,以允许生物在保护区之间移动。这种方法已经得以法规化,例如《美国濒危物种法案(Endangered Specles Act inthe United States)》和《生物多样性公约(Biodlversity Treaty)》。这两个法案都逐一列出了应当保护的濒危物种,但都存在着明显的缺陷。这些做法可能是适当的,但是作为拥有60亿人口、掌握着毁灭性技术、为了直接的人类利益而事实上开发了所有的地球资源的世界性保护活动,却是不充分的。作为包括人类在内的所有生物体的栖息地,生物圈的功能正在迅速衰退,这并不是因为物种的消失,而是因为自然群落的不断贫化,这种贫化是由于全球性、普遍存在的人类活动的慢性破坏而产生的。这种自然群落的贫化导致了演变中的环境功能的紊乱,功能紊乱的累积,最后导致了物种的消失。其实,远在物种消失这一问题变得如此重要之前,局地的生物生态型就受到损失了,这在遗传学上是非常清楚的,而且它们赖以发育的自然群落就变得贫化,功能出现了紊乱。最明显的影响是气候上的,这是每一个生态系统都经历的环境的全球变化。自然保护区的最精细、最谨慎的连结方式也无法发挥作用,因为其环境气候发生了改变,而且生物多样性将大幅度丧失。尽管所建立的公园就是为了避免这种丧失,但是在这之前,人类环境就将遭受显著破坏。自然保护的目的,是保存景观(以及水体)的功能整体性。其重点往往是地球上天然林区的森林,因为森林占据了地球上很大的面积,而且对环境的每一方面都有很大影响。在大多数地方,功能的整体需要85%或以上的天然林区结构的整体性。当然,这还需要科学界的客观测定和定义。这样看来,自然保护的实质就发生了变化,它并不是所谓的生物多样性的保存,而是人类环境功能整体性的保存,其核心目的是要求我们以民主形式建立的政府,定义并保护公共利益。现在已经不是迫切需要科学界和保护界认识这种转变、定义新的保护目的以及将这种转变告诉公众的时候了,而是迫切需要政府承担起在这样的责任,即在一个可以栖息的生物圈之中保护公众的利益。

关键词：科学功能整体性生物多样性环境保护自然保护生物整体性政府目的