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Discovery of native aluminum and its possible origin from prospective gas hydrate areas in the South China Sea

Science China Earth Sciences 2010年第3期53卷 335-344页

作者： CHEN Zhong HUANG ChiYue WU BiHao ZHAO MeiXun YAN Wen Key Laboratory of Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Department of Earth Sciences Cheng Kung UniversityTainan 701China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Marine Chemistry Theory and Technology of the Ministry of Education Ocean University of ChinaQingdao 266100China

Aluminum is an active amphoteric metal element, but native aluminum (Al°) can be formed and preserved in special condi- tions so that its occurrence has unique geological significance. In this paper, the coarse fractions (> 63 μm) of 269 samples of surface sediments and of 165 sediment samples in four cores from the South China Sea (SCS) were picked out and analyzed. Al° particles were found in only five surface samples and three samples in two sedimentary cores. The particles are grayish or silver white in color with a strongly metallic luster and high plasticity, and they occur as irregular plats, elongated shapes and spherules with botryoidal structures. The identified Al° particles belong to cubical system, Fm3m space group with a varying from 4.028×10?1 nm to 4.059×10?1 nm. Their chemical compositions consist mainly of Al (95.07%–99.84%) and minor amounts of Si, Fe, Ti, S, Zn, Mg, Ca and trace amounts of K, Na, Cu, Co, P and Mn. Our results show that the identified Al° is authigenic, formed in situ in the prospective areas of gas hydrates, and that it is an unreported type of Al° occurrence. A possi- ble mechanism of Al° formation is proposed: under the strongly reducing micro environments at cold seeps, dissolved Al3+ in sediments is reduced to its metallic state by the strongly reducing agent of H2 through microbial processes and enzyme action. As a result, the Al° particles from the prospective gas hydrate areas in the SCS are the special products, representing the first report on Al° from the sediments at cold seeps. The proposed mechanism provides a theoretical basis for further studies on the special biogeochemical processes at cold seeps.

关键词： native aluminum cold seep gas hydrate reducing environment South China Sea

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Gastric cancer in Alaska native people: A cancer health disparity

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World Journal of Gastroenterology 2018年第25期24卷 2722-2732页

作者： Holly A Martinson Nancy J Shelby Steven R Alberts Matthew J Olnes WWAMI School of Medical Education University of Alaska Anchorage Department of Oncology Mayo Clinic Cancer Center Hematology and Medical Oncology Department Alaska Native Medical Center

AIM To evaluate recent trends in gastric cancer incidence, response to treatment, and overall survival among Alaska native(AN) people. METHODS A retrospective analysis of the Alaska native Medical Center patient database was performed. Patient history, clinical, pathological, response to treatment and patient outcomes were collected from one-hundred and thirty-two AN gastric cancer patients. The Surveillance, Epidemiology and End Result database 18 was used to collect comparison United States non-Hispanic White(NHW) and AN gastric cancer patient data between *** AN gastric cancer patients have a higher incidence rate, a poorer overall survival, and are diagnosed at a significantly younger age compared to NHW patients. AN patients differ from NHW patients in greater prevalence of non-cardia, diffuse subtype, and signet ring cell carcinomas. AN females were more likely to be diagnosed with later stage cancer, stage IV, compared to AN males. Diminished overall survival was observed among AN patients with increasing stage, O+ blood type, < 15 lymph nodes examined at resection, and no treatment. This study is the first report detailing the clinicopathologic features of gastric cancer in AN people with outcome *** Our findings confirm the importance of early detection, treatment, and surgical resection for optimizing AN patient outcomes. Further research on early detection markers are warranted.

关键词： Alaska native gastric cancer Helicobacter pylori gender health disparities

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Spatial dynamic patterns of saltmarsh vegetation in southern Hangzhou Bay:Exotic and native species

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Water Science and Engineering 2020年第1期13卷 34-44页

作者： Si-long Huang Yi-ning Chen Yan Li Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Dongshan Swire Marine Station Xiamen UniversityXiamen 361005China

A saltmarsh has developed rapidly on the mudflat of Andong Shoal,in southern Hangzhou Bay,over the last decade since *** saltmarsh vegetation changes are driven by both sediment dynamic conditions and the competition between the exotic species Spartina alterniflora(***) and the native species Scirpus mariqueter(***).This study attempted to investigate large-scale spatial variations in the exotic and native species,by analyzing and interpreting a time series(2016-2018) of high-resolution(less than 1 m) remote sensing *** total area of the saltmarsh increased at a rate of 1.07 km^2/year,due to the accretion of the whole tidal *** spatial patterns revealed a new bimodal pattern for *** *** expanded over the upper to middle saltmarsh at a rate of1.68 km2/***,the *** patches at the seaward edge expanded at a negative rate of-0.005 km^2/year,indicating a different pattern in competition:*** had more advantages in the upper saltmarsh,while *** had more advantages in the pioneer zone with low ***,*** mainly established new habitats by invading *** in the middle saltmarsh,but *** occupied the bare mudflat for *** results aindicated that the interspecific competition result between *** and *** depended on elevation,and low elevation might create a favorable environment for *** to win the competition with exotic *** finding could be applied to future invasive species control and saltmarsh management.

关键词： Saltmarsh Spartina alterniflora Scirpus mariqueter Spatial variation Competition Exotic species native species

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Type 1 diabetes loci display a variety of native American and African ancestries in diseased individuals from Northwest Colombia

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World Journal of Diabetes 2019年第11期10卷 534-545页

作者： Natalia Gomez-Lopera Juan M Alfaro Suzanne M Leal Nicolas Pineda-Trujillo Departamento de Pediatría Facultad de MedicinaUniversidad de AntioquiaMedellín 050010470Colombia Sección de Endocrinología Pediátrica Departamento de PediatríaFacultad de MedicinaUniversidad de AntioquiaMedellín 050010470Colombia Center for Statistical Genetics Columbia UniversityNew YorkNY 10032United States

BACKGROUND Type 1 diabetes(T1D)is a complex disease with a higher incidence in Europeans than other *** Colombians Living in Medellin(CLM)is admixed with ancestry contributions from Europeans,native Americans(NAT)and Africans(AFR).AIM Our aim was to analyze the genetic admixture component at candidate T1D loci in Colombian individuals with the *** Seventy-four ancestry informative markers(AIMs),which tagged 41 T1D candidate loci/genes,were tested by studying a cohort of 200 Northwest Colombia diseased individuals.T1D status was classified by testing for glutamic acid decarboxylase(GAD-65 kDa)and protein tyrosine-like antigen-2 autoantibodies in serum *** loci/genes included HLA,INS,PTPN22,CTLA4,IL2RA,SUMO4,CLEC16A,IFIH1,EFR3B,IL7R,NRP1 and RNASEH1,amongst *** 1,000 genome database was used to analyze data from 94 individuals corresponding to the reference *** the data did not comply with a normal distribution,medians were compared between groups using the Mann-Whitney *** Both T1D patients and individuals from CLM displayed mainly European ancestry(61.58 vs 62.06)followed by native American(27.34 vs 27.46)and to a lesser extent the AFR ancestry(10.28 vs 10.65)***,compared to CLM,ancestry of T1D patients displayed a decrease of NAT ancestry at gene EFR3B(24.30 vs 37.10)and an increase at genes IFIH1(32.07 vs 14.99)and IL7R(52.18 vs 39.18).Also,for gene NRP1(36.67 vs 0.003),we observed a non-AFR contribution(attributed to NAT).Autoimmune patients(positive for any of two auto-antibodies)displayed lower NAT ancestry than idiopathic patients at the MHC region(20.36 vs 31.88).Also,late onset patients presented with greater AFR ancestry than early onset patients at gene IL7R(19.96 vs 6.17).An association analysis showed that,even after adjusting for admixture,an association exists for at least seven such AIMs,with the strongest findings on chromosomes 5 and 10(gene IL7R,P=5.56×10-6 and gene NRP1,P=8.

关键词： Type 1 diabetes Genetic admixture native American Idiopathic Colombia

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native XML数据库并发控制协议

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计算机工程 2009年第14期35卷 35-37页

作者：魏东平孙华国宗德君中国石油大学计算机科学系东营257061

并发控制是改善数据库系统事务性能的最重要机制,也是native XML数据库研究领域的一个难点。通过简化XPath数据模型,定义基于该模型的几种native XML数据库操作,提出一种新的基于XPath的加锁协议,分析该协议下的调度是可串行化调度,并... 详细信息

并发控制是改善数据库系统事务性能的最重要机制,也是native XML数据库研究领域的一个难点。通过简化XPath数据模型,定义基于该模型的几种native XML数据库操作,提出一种新的基于XPath的加锁协议,分析该协议下的调度是可串行化调度,并针对其性能问题进行探讨。

关键词： native XML数据库并发控制可串行化

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native XML数据库的增量式验证

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计算机研究与发展 2006年第Z3期43卷 424-429页

作者：王鑫袁晓洁李楠南开大学计算机科学与技术系天津300071 南开大学计算机科学与技术系天津300071 南开大学计算机科学与技术系天津300071

针对native XML数据库的更新操作,提出了一种增量式验证方法,确保更新后的XML数据仍然符合指定模式的约束.基于正则树文法理论,形式化地描述XML模式语言,给出DTD在native XML数据库中的表示与存储格式.在更新操作过程中,首先检验期望结... 详细信息

针对native XML数据库的更新操作,提出了一种增量式验证方法,确保更新后的XML数据仍然符合指定模式的约束.基于正则树文法理论,形式化地描述XML模式语言,给出DTD在native XML数据库中的表示与存储格式.在更新操作过程中,首先检验期望结果是否满足模式的约束;只有在更新操作通过验证的前提下,原始XML数据才允许被修改.由于增量式验证仅涉及到直接受更新操作影响的XML数据片段.因此,与完全重新验证相比,增量式验证可以极大地提高XML数据更新效率.

关键词：增量式验证 native XML数据库 XML模式更新操作 DTD

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native Expanding <i>Merremia boisiana</i>Is Not More Allelopathic than Its Non-Expanding Congener <i>M. vitifolia</i>in the Expanded Range in Hainan

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American Journal of Plant Sciences 2013年第4期4卷 774-779页

作者： Qiaoqiao Huang Yide Shen Xiaoxia Li Zhiwei Fan Mingguang Li Hanting Cheng Environment and Plant Protection Institute Chinese Academy of Tropical Agricultural Sciences Haikou China State Key Laboratory of Biocontrol School of Life Sciences Sun Yat-sen University Guangzhou China

Exotic invaders may possess novel biochemical weapons that native plants do not have, and these novel biochemical weapons may be more allelopathic than those from native plants to other native competitors. During range expansion, native species also encounter many new plant competitors. Thus, allelochemicals from native expanding species may also be more novel and allelopathic than those from non-expanding species to other plant competitors in the expanded range. We test this hypothesis using the native expanding Merremia boisiana and its non-expanding congener M. vitifolia in year 2012 inthe expanded range inHainan. In petridish bioassays, we found that aqueous extracts of M. boisiana leaves were often less inhibitory or more stimulatory to seed germination and seedling growth of five vegetable species than those of M. vitifolia leaves. In pot culture, we also found that aqueous leaf extracts of the two congeners could both inhibit the growth of a naturally co-occurring plant Paederia scanden, but their effects did not differ from each other. These results indicate that while allelopathy may contribute to the competitive ability of M. boisiana, it may not act as a novel weapon explaining its success in the expanded range in Hainan.

关键词： Allelopathy Expansion Invasion Merremia boisiana native Expanding Species Novel Weapons

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native XML数据库的文档编码机制研究

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计算机工程与应用 2008年第12期44卷 147-150,181页

作者：张鹏冯建华韩秀峰清华大学计算机科学与技术系北京100084 首都经济贸易大学金融学院北京100070

native XML数据库快速查询的实现,可以采用基于XML文档编码的结构连接算法。而结构连接算法的实现需要对XML文档进行编码,以便于快速判断XML文档树结点之间的祖先后裔关系。在对现有编码机制进行综述的前提下,提出一种新的XML文档编码... 详细信息

native XML数据库快速查询的实现,可以采用基于XML文档编码的结构连接算法。而结构连接算法的实现需要对XML文档进行编码,以便于快速判断XML文档树结点之间的祖先后裔关系。在对现有编码机制进行综述的前提下,提出一种新的XML文档编码机制——前缀整除编码(PDIV)机制。该机制编码形式简单,只需要一个正整数即可充分表示结点在XML文档树中的位置信息;可以实现祖先后裔关系的快速查询;支持XML文档的更新操作;编码长度较短,编码长度约为o(ln(n))。

关键词： native XML数据库编码机制 XML查询

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native XML数据库的结构连接算法研究

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计算机应用 2008年第4期28卷 869-871,880页

作者：张鹏冯建华房志峰清华大学计算机科学与技术系北京100084 山东政法学院信息科学技术系济南250014

native XML数据库的快速查询,可以通过基于XML文档编码的结构连接算法实现。在对现有结构连接算法进行综述的前提下,提出一种新的native XML数据库的结构连接算法---基于深度均匀划分的结构连接算法(DRIAM)。该算法不要求输入数据AList... 详细信息

native XML数据库的快速查询,可以通过基于XML文档编码的结构连接算法实现。在对现有结构连接算法进行综述的前提下,提出一种新的native XML数据库的结构连接算法---基于深度均匀划分的结构连接算法(DRIAM)。该算法不要求输入数据AList和DList有序或在其节点编码上建有索引,避免了排序和索引所增加的额外开销;不需要输入数据AList和Dlist全部加载到内存中,可以适应不同内存大小限制的情况,并且该算法时间复杂度非常低。

关键词： native XML数据库 XML查询结构连接

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native Speaker and L2 User in Language Teaching

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海外英语 2012年第5X期 61-63页

作者：张可科宁波城市职业技术学院外国语学院浙江宁波315000

The target of much language teaching and learning is to make students approximate to native *** only rightful speak ers of a language are its native *** to these contemporary views,however,this paper argues that the obligation of the lan guage teacher is to help students to use L2 effectively not to simply imitate native speaker.A successful L2 user who comes from the group of L2 learners can be a model for ***,non-native teachers with a high degree of language proficiency and good teaching skills can be ideal and qualified language teachers.

关键词： language teaching native speaker L2 user non-nativ

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