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Species-area relationship within and across functional groups at alpine grasslands on the northern Tibetan Plateau,China

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Journal of Mountain Science 2016年第2期13卷 265-275页

作者： ZHOU Nan WU Jian-shuang SHEN Zhen-xi ZHANG Xian-zhou yang peng-wan Lhasa National Ecological Research Station Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of sciences University of Chinese Academy of Sciences Functional Biodiversity Dahlem Centre of Plant SciencesFree University of Berlin

The species-area relationship （SAR） is one of the most fundamental concepts in community ecology and is helpful for biodiversity conservation. However, few studies have systematically addressed this topic for different alpine grassland types on the Tibetan Plateau, China. We explored whether the plant composition of different functional groups affects the manner in which species richness inereases with increasing area at scales ≤ 1.0 m^2. We also compared species richness （S） within and across forbs, legumes, sedges and grasses, with sampling subplot area （A） increasing from 0.0625 m^2 to 1.0 m^2 between alpine meadow and steppe communities. We applied a logarithmic function （S = b0 ＋ b1 ln A） to determine the slope and intercept of SAR curves within and across functional groups. The results showed that the logarithmic relationship holds true between species richness and sampling area at these small scales. Both the intercept and slope of the logarithmic forbs-area curves are significantly higher than those for the three other functional groups （P 〈 0.05）. Forb accounts for about 91.9 % of the variation in the intercept and 75.0% of the variation in the slope of the SAR curve when all functional groups＇ data were pooled together. Our results indicated that the different SAR patterns should be linked with species dispersal capabilities, environmental filtering, and life form composition within alpine grassland communities. Further studies on the relationship between species diversity and ecosystem functions should specify the differential responses of different functional groups to variations in climate and anthropogenic disturbances.

关键词： Changtang Nature Reserve Complementary response Plant functional groups Plant life forms Species coexistence

Response of Ecosystem Respiration to Experimental Warming and Clipping at Daily Time Scale in an Alpine Meadow of Tibet

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Journal of Mountain Science 2013年第3期10卷 455-463页

作者： FU Gang SHEN Zhen-xi ZHANG Xian-zhou YU Cheng-qun ZHOU Yu-ting LI Yun-long yang peng-wan Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences

The alpine meadow, as one of the typical vegetation types on the Tibetan Plateau, is one of the most sensitive terrestrial ecosystems to climate warming. However, how climate warming affects the carbon cycling of the alpine meadow on the Tibetan Plateau is not very dear. A field experiment under controlled experimental warming and clipping conditions was conducted in an alpine meadow on the Northern Tibetan Plateau since July 2008. Open top chambers （0TCs） were used to simulate climate warming. The main objective of this study was to examine the responses of ecosystem respiration （Reco） and its temperature sensitivity to experimental warming and clipping at daily time scale. Therefore, we measured Reco once or twice a month from July to September in 2010, from June to September in 2011 and from August to September in 2012. Air temperature dominated daily variation of Reco whether or not experimental warming and clipping were present. Air temperature was exponentially correlated with Reco and it could significantly explain 58-96% variation of Redo at daily time scale. Experimental warming and clipping decreased daily mean Reco by 5.8-37.7% and -11.9-23.0%, respectively, although not all these changes were significant. Experimental warming tended to decrease the temperature sensitivity of Reco, whereas clipping tended to increase the temperature sensitivity of Reco at daily time scale. Our findings suggest that Reco wasmainly controlled by air temperature and may acclimate to climate warming due to its lower temperature sensitivity under experimental warming at daily time scale.

关键词： Acclimation Air temperature Open topchamber Temperature sensitivity Respirationquotient ( Q10)

Clipping Alters the Response of Biomass Production to Experimental Warming: A Case Study in an Alpine Meadow on the Tibetan Plateau, China

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Journal of Mountain Science 2015年第4期12卷 935-942页

作者： FU Gang SUN Wei YU Cheng-Qun ZHANG Xian-Zhou SHEN Zhen-Xi LI Yun-Long yang peng-wan ZHOU Nan Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

Predicting how human activity will influence the response of alpine grasslands to future warming has many *** this study, a field experiment with controlled warming and clipping was conducted in an alpine meadow at three elevations（4313 m, 4513 m and 4693 m） in Northern Tibet to test the hypothesis that clipping would alter warming effect on biomass *** top chambers（OTCs） were used to increase temperature since July,2008 and the OTCs increased air temperature by approximately 0.9o C ~ 1.8o C during the growing *** was conducted three times one year during growing season and the aboveground parts of all live plants were clipped to approximately 0.01 m in height using scissors since *** primary production（GPP） was calculated from the Moderate-Resolution Imaging Spectroradiometer GPP algorithm and aboveground plant production was estimated using the surface-measured normalized difference vegetation index in *** decreased the GPP, aboveground biomass（AGB） and aboveground net primary production（ANPP） at all three elevations when clipping was not *** contrast, warming increased AGB at all three elevations, GPP at the two lower elevations and ANPP at the two higher elevations when clipping was *** findings show that clipping reduced the negative effect of warming on GPP, AGB and ANPP, suggesting that clipping may reduce the effect of climate warming on GPP, AGB and ANPP in alpine meadows on the Tibetan Plateau, and therefore, may be a viable strategy for mitigating the effects of climate change on grazing and animal husbandry on the Tibetan Plateau.

关键词： Clipping Gross primary production Open top chamber Warming Alpine Meadow Tibetan Plateau

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杨家矿井煤与瓦斯突出防治的思考

矿业安全与环保 2010年第S1期37卷 103-105页

作者：杨万鹏羊场煤矿云南宣威655411

针对杨家矿井煤与瓦斯突出防治的实践,探索杨家矿井煤与瓦斯突出特征及防治措施,编制矿井综合防突方案,以指导矿井防突工作,提高煤与瓦斯突出防治效果。

关键词：生产矿井煤与瓦斯突出防治

高性能镍基粉末高温合金中γ′相形态致锯齿晶界形成机理研究

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材料工程 2015年第6期43卷 7-13页

作者：杨万鹏胡本芙刘国权吴凯北京科技大学材料科学与工程学院北京100083 北京科技大学新金属材料国家重点实验室北京100083

采用光学显微镜、场发射扫描电子显微镜和透射电子显微镜,系统研究了低错配度的第三代高性能粉末高温合金(FGH98I)在热处理条件下由合金晶界上γ′相不同析出行为造成的锯齿晶界。结果表明:在晶界上析出γ′相形态不同是锯齿晶界形成的... 详细信息

采用光学显微镜、场发射扫描电子显微镜和透射电子显微镜,系统研究了低错配度的第三代高性能粉末高温合金(FGH98I)在热处理条件下由合金晶界上γ′相不同析出行为造成的锯齿晶界。结果表明:在晶界上析出γ′相形态不同是锯齿晶界形成的主导因素。热处理时固溶冷却速率不同,晶界上析出的γ′相数量、尺寸和形态不同,对晶界锯齿形状有强烈影响。当冷却速率由0.1℃/s增大至10.8℃/s时,晶界锯齿振幅由4.02μm变为0.63μm,锯齿的波长则随冷却速率增大而变大。γ′相形态失稳的不同形状和尺寸是造成晶界锯齿振幅大小的主要因素。晶界两侧分布着不同密度的γ′相颗粒,也可使晶界发生位移形成波浪式小振幅锯齿晶界。根据实验结果,提出了有关锯齿晶界的形成模式。

关键词：粉末高温合金 γ'相锯齿晶界

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常见轴孔的高精度定位算法研究及应用

制造业自动化 2022年第12期44卷 161-165页

作者：杨万鹏胡伟河南理工大学电气与自动化学院焦作454002

针对自动化装配场景中的轴孔目标定位检测过程,成像质量不高、特征区域边缘模糊和定位精度低的问题,采用形态学处理提高图像质量,用同态增晰的算法来增强边缘特征,最后用最小二乘法Huber圆拟合算法拟合圆,梯度下降算法求出圆心,最终实... 详细信息

针对自动化装配场景中的轴孔目标定位检测过程,成像质量不高、特征区域边缘模糊和定位精度低的问题,采用形态学处理提高图像质量,用同态增晰的算法来增强边缘特征,最后用最小二乘法Huber圆拟合算法拟合圆,梯度下降算法求出圆心,最终实现高精度定位。通过数据分析和现场实际测试验证,该算法定位精度高,运行速度快,并且运行稳定。

关键词：机器视觉形态学同态增晰最小二乘法梯度下降

Targeted gene sequencing and bioinformatics analysis of patients with gallbladder neuroendocrine carcinoma:A case report

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 239-251页

作者： Yun-Chuan yang Zhi-Tao Chen Da-Long wan Hui Tang Mu-Lin Liu Department of Medical College Jinan UniversityGuangzhou 510000Guangdong ProvinceChina Department of General Surgery The First Affiliated Hospital of Bengbu Medical UniversityBengbu 233000Anhui ProvinceChina Department of Hepatobiliary Surgery Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310022Zhejiang ProvinceChina Department of Hepatobiliary and Pancreatic Surgery The First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310003Zhejiang ProvinceChina Department of Pathology The First Affiliated Hospital of Medical School of Zhejiang UniversityHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Gallbladder neuroendocrine carcinoma(NEC)represents a subtype of gallbladder malignancies characterized by a low incidence,aggressive nature,and poor *** its clinical severity,the genetic alterations,mechanisms,and signaling pathways underlying gallbladder NEC remain *** SUMMARY This case study presents a rare instance of primary gallbladder NEC in a 73-year-old female patient,who underwent a radical cholecystectomy with hepatic hilar lymphadenectomy and resection of liver segments IV-B and *** gene sequencing and bioinformatics analysis tools,including STRING,GeneMANIA,Metascape,TRRUST,Sangerbox,cBioPortal and GSCA,were used to analyze the biological functions and features of mutated genes in gallbladder *** mutations(APC,ARID2,IFNA6,KEAP1,RB1,SMAD4,TP53,BTK,GATA1,GNAS,and PRDM3)were identified,and the tumor mutation burden was determined to be 9.52 muts/Mb via targeted gene sequencing.A protein-protein interaction network showed significant interactions among the twelve mutated *** Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were used to assess mutation functions and *** results revealed 40 tumor-related pathways.A key regulatory factor for gallbladder NEC-related genes was identified,and its biological functions and features were compared with those of gallbladder *** Gallbladder NEC requires standardized *** with other gallbladder carcinomas revealed clinical phenotypes,molecular alterations,functional characteristics,and enriched pathways.

关键词： Gallbladder neuroendocrine carcinoma Targeted-gene sequencing Bioinformatics analysis case report Immunocytochemistry Case report

Targeting capabilities of engineered extracellular vesicles for the treatment of neurological diseases

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Neural Regeneration Research 2025年第11期20卷 3076-3094页

作者： Xinyu yang Xiangyu Gao Xiaofan Jiang Kangyi Yue peng Luo Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina

Recent advances in research on extracellular vesicles have significantly enhanced their potential as therapeutic agents for neurological *** to their therapeutic properties and ability to cross the blood–brain barrier,extracellular vesicles are recognized as promising drug delivery vehicles for various neurological conditions,including ischemic stroke,traumatic brain injury,neurodegenerative diseases,glioma,and ***,the clinical application of natural extracellular vesicles is hindered by their limited targeting ability and short clearance from the *** address these limitations,multiple engineering strategies have been developed to enhance the targeting capabilities of extracellular vesicles,thereby enabling the delivery of therapeutic contents to specific tissues or ***,this review aims to highlight the latest advancements in natural and targeting-engineered extracellular vesicles,exploring their applications in treating traumatic brain injury,ischemic stroke,Parkinson's disease,Alzheimer's disease,amyotrophic lateral sclerosis,glioma,and ***,we summarized recent clinical trials involving extracellular vesicles and discussed the challenges and future prospects of using targeting-engineered extracellular vesicles for drug delivery in treating neurological *** review offers new insights for developing highly targeted therapies in this field.

关键词： Alzheimer's disease amyotrophic lateral sclerosis engineered extracellular vesicles glioma ischemic stroke neurological diseases Parkinson's disease psychosis targeted drug delivery traumatic brain injury

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中英文化差异对谚语翻译策略的影响

长江大学学报（社会科学版） 2006年第5期29卷 95-97页

作者：杨万鹏长江大学外国语学院湖北荆州434023

英汉谚语作为两种文化的载体,分别反映出两种文化的共性与个性。这种共性与个性直接影响甚至决定着两种谚语之间的翻译策略。为了保持翻译的交际功能,同时充分体现两种谚语的文化内涵,在两种谚语的翻译中必须采取异化、归化、借用和综... 详细信息

英汉谚语作为两种文化的载体,分别反映出两种文化的共性与个性。这种共性与个性直接影响甚至决定着两种谚语之间的翻译策略。为了保持翻译的交际功能,同时充分体现两种谚语的文化内涵,在两种谚语的翻译中必须采取异化、归化、借用和综合翻译法。

关键词：中英谚语文化特征翻译策略