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Species richness and biodiversity significance of alpine micro-waterbody systems in Gaoligong Mountain, Northwest Yunnan, China

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Journal of Mountain Science 2020年第4期17卷 907-918页

作者： LIU shuo-Ran Davide FORNACCA yang Dao-De TAN Lu LI Xian-Fu REN Guo-Peng SUN Jun HE Xiao-yang yang wen-shu CAI Qing-Hua XIAO wen Institute of Wildlife Conservation Central South University of Forestry and TechnologyChangsha 410004China Institute of Materia Medica Dali UniversityDali 671003China Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China Dali 671003China Institute of Eastern-Himalaya Biodiversity Research Dali UniversityDali 671003China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Gong-shan Administration Bureau Gao-li-gong Mountain National Nature ReserveNujiang 67350China

Water quality, size, connectivity and other physical properties of hydrological systems might have different functions in the formation and maintenance of biodiversity, but this remains mostly unclear due to the lack of undisturbed sites for experimental modelling. Alpine freshwater habitats such as micro-waterbodies(MWB) represent a kind of natural system suitable for biodiversity research. In order to assess potential linkages between environmental factors, connectivity of MWBs and aquatic species richness, we conducted a pilot study in two separated MWB systems located in Gaoligong Mountain, northwest Yunnan province, China. A total of 27 MWBs have been analyzed, including 22 connected and 5 isolated bodies. 13 conventional environmental factors were tested while all kinds of aquatic macro-organisms were collected and classified. Results showed a high environmental heterogeneity among MWBs and significant differences between the two systems but only a few environmental variables such as the depth of soil bottom, total Nitrogen and altitude were related to species richness and the formation of the community structure. As a benefit from the high environmental heterogeneity, the cascaded MWB systems provided divergent habitats able to support species richness at a higher level than the same number of randomly selected MWBs. This finding supports the idea that habitat connectivity matters also in extremely small aquatic ecosystems. Moreover, although still a preliminary result, a polarization effect within connected chains where edge MWBs host higher taxa and endemic taxa richness as well as larger populations, was detectable. This study gives interesting insights on the spatial processes driving community structure and a new prospective for biodiversity conservation. Since alpine MWBs have significant effects on the maintenance of watershed biodiversity, further research on such small and crucial ecosystems is encouraged.

关键词： Habitat connectivity High mountain Extreme fine scale Cascaded water system Richness maintenance Polarized dispersal

Phase Noise Monitor and Reduction by Parametric Saturation Approach in Phase Modulation Systems

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Chinese Physics Letters 2011年第2期28卷 97-100页

作者： XU Ming ZHOU Zhen PU Xiao JI Jian-Hua yang shu-wen Advanced Technology Research Center of Information Engineer Academy in Shenzhen University Shenzhen 518060

Nonlinear phase noise(NLPN)is investigated theoretically and numerically to be mitigated by parametric saturation approach in DPSK *** nonlinear propagation equation that incorporates the phase of linear and nonlinear is analyzed with parametric saturation processing(PSP).The NLPN is picked and monitored with the power change factors in the DPSK *** process can be realized by an optical PSP limiter and a novel apparatus with feedback *** monitor range of phase noise is 0°-90°,which may be reduced to 0°-45°if the monitor factor is about the Stockes wave but not an anti-Stockes *** is shown that DPSK signal performance can be improved based on the parametric saturation approach.

关键词： DPSK saturation parametric

Effects of extrusion deformation on mechanical properties of sub-micron Si_(3)N_(4p)/2024 composite

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Transactions of Nonferrous Metals Society of China 2009年第S02期19卷 373-377页

作者： XIU Zi-yang CHEN Guo-qin LIU Yan-mei yang wen-shu WU Gao-hui Academy of Fundamental and Interdisciplinary Sciences Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Si_(3)N_(4p)/2024Al composite was fabricated by squeeze casting method and treated by extrusion *** analyses indicate that Si_(3)N_(4) particles in the composite are in cylindrical polyhedron *** deformation is beneficial to uniform distribution of Si_(3)N_(4) particles and improves the relative density of Si_(3)N_(4p)/2024Al *** strength of Si_(3)N_(4p)/2024Al composite increases by 76.6%after T6 treatment,and after extrusion and T6 treatment it is by 57.6%more than T6 treatment *** modulus of Si_(3)N_(4p)/2024Al composite increases a little after T6 treatment but increases by 33.5%after extrusion deformation.

关键词： Si_(3)N_(4p)/2024Al composite extrusion deformation mechanical properties

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OCDMA技术的研究现状及发展

光通信技术 2011年第8期35卷 13-18页

作者：杨淑雯深圳大学广东深圳518060

OCDMA技术是新一代的全光技术,可以广泛用于光信道多路复用、光网络多址接入、光码标记交换核心网、光信号安全传输、光纤传感以及光载无线系统等。概述了光码分多址(OCDMA)技术的研究现状、主要关键技术,并展望其发展趋势和应用前景。

关键词：光码分多址光码光编口解码光码分多址接入光码分多址网络

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无穷区间上一类二阶泛函微分方程的边值问题

纺织高校基础科学学报 2012年第1期25卷 51-54页

作者：杨雯抒嘉应学院数学学院广东梅州514015

研究了无穷区间上一类二阶泛函微分方程边值问题解的存在性.采用Schauder不动点定理和压缩映像原理研究此边值问题,得到了该方程边值问题存在唯一解的一些结果,并发展了以前文献中的一些结论.

关键词：泛函微分方程边值问题 Schauder不动点定理存在性

Improvement of normalized throughput in WDM+OCDMA system using optical hard-limiters

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Optoelectronics Letters 2006年第1期2卷 55-57页

作者： JI Jian-hua XU Ming yang shu-wen ZHANG Zhi-peng Advanced Technology Research Center of Shenzhen University Shenzhen 518060 China

A scheme of WDM＋ OCDMA system employing optical hard-limiter（OHL） is proposed, and its performance of normalized throughput is analyzed. The upper bound of the normalized throughput is obtained when all the simultaneous users are equally allocated to different wavelength channels. The lower bound of the normalized throughput is obtained when all the simultaneous users are firstly allocated to the same wavelength channels. Compared with the performance of VVDM＋ OCDMA system without OHL, both the upper bound and lower bound of the normalized throughput in WDM ＋ OCDMA system with OHL can be improved.

关键词：光纤通信 WDM OCDMA 波长通信信道

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光接入网网络管理系统设计

深圳大学学报（理工版） 2006年第1期23卷 31-35页

作者：杨芳杨淑雯张小健深圳大学信息工程学院深圳518060 中国联通深圳分公司深圳518057

提出一种基于Web界面,具有分布式处理功能,能适应多种网络环境的光接入网网络管理系统,该系统采用浏览器-总管理者-次管理者-光接入网设备4级分层结构,系统功能独立,扩展负载均衡,功能实现上使用了CORBA面向对象的客户/服务器分布式程... 详细信息

提出一种基于Web界面,具有分布式处理功能,能适应多种网络环境的光接入网网络管理系统,该系统采用浏览器-总管理者-次管理者-光接入网设备4级分层结构,系统功能独立,扩展负载均衡,功能实现上使用了CORBA面向对象的客户/服务器分布式程序设计思想,利用Java语言作为主要开发语言.

关键词：光接入网网络管理 SNMP CORBA

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32种中草药抑菌活性的比较研究

安徽农业科学 2011年第3期39卷 1361-1362,1366页

作者：杨淑文铁岭师范高等专科学校生物组辽宁铁岭112000

[目的]研究连翘(FRUCTUS FORSYTHIAE)、黄连(RHIZOMA COPTIDIS)和刺五加(RADIX ET RHIZOMA SEU CAULIS ACAN-THOPANACTS SENTICOSI)等32味中草药提取物的抑菌作用。[方法]利用95%乙醇提取药物的有效成分,以大肠杆菌和金黄色葡萄球菌为指示菌,采用牛津杯法测定中草药提取物的抑菌作用。[结果]32种中草药中,虎杖等26种中草药提取物对金黄色葡萄球菌具有抑制作用;连翘等23种中草药提取物对大肠杆菌具有抑制作用,且抑菌效果在一定浓度范围内随药液浓度的增大而增强。其中,连翘和黄连对大肠杆菌的最低抑菌浓度分别是4和10 mg/ml,对金黄色葡萄球菌的最低抑菌浓度分别是6和8 mg/ml。[结论]虎杖和连翘分别对金黄色葡萄球菌和大肠杆菌具有较好的抑制效果。

关键词：中草药抑菌作用最低抑菌浓度

Cholangiocarcinoma accompanied by desmoid-type fibromatosis

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Hepatobiliary & Pancreatic Diseases International 2011年第2期10卷 214-217页

作者： Nan Xu,Zhe-Yu Chen,Lu-Nan Yan,Jia-Ying yang,wen-Tao Wang and shu-Guang JingDepartment of Liver and Vascular Surgeryand Department of Hepato-biliary-pancreatic Surgery,West China Hospital,Sichuan University, Chengdu 610041,China [a] Department of Liver and Vascular Surgery West China Hospital Sichuan University Chengdu 610041 China [b] Department of Hepato-biliary-pancreatic Surgery West China Hospital Sichuan University Chengdu 610041 China

BACKGROUND:Cholangiocarcinoma complicated by intraabdominal desmoid-type fibromatosis(DTF)is uncommon. There are no reports on patients with this type of fibromatosis, in which the pre-operative treatment(including diagnosis), surgical approach,post-operative pathologic reports,and prognosis are discussed. METHOD:The clinicopathological features of a 49-year-old man were retrospectively analyzed. RESULTS:Cholangiocarcinoma located in the inferior segment of the bile duct was considered pre-operatively on the basis of clinical *** the time of pancreaticoduodenectomy,the mesojejunum was stiff without nodules or a mass at a distance of approximately 80 cm from the ligament of *** excision of the entire lesion of the intestinal mesenteric contracture and its subsidiary was ***-operative pathologic findings confirmed an adenocarcinoma located at the extremity of the common bile duct and infiltrating the full thickness of the common bile duct as well as the deep muscular layer of the *** contracted jejunal mesentery was shown to have *** patient was alive with no evidence of recurrence after a follow-up of 6 months. CONCLUSIONS:The patient had a rare hereditary disease with intra-abdominal DTF,which manifests the characteristics of an aggressive growth pattern and a high rate of local recurrence; conservative therapy is *** excision of the fibromatous lesion during pancreaticoduodenectomy may maximally decrease the risk of local recurrence.

关键词： cholangiocarcinoma desmoid-type fibromatosis diagnosis pancreaticoduodenectomy pathology