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Effects of long-term grazing exclusion on vegetation structure,soil water holding capacity,carbon and nitrogen sequestration capacity in an alpine meadow on the Tibetan Plateau

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Journal of Mountain Science 2023年第3期20卷 779-791页

作者： YANG yong-sheng ZHANG Fa-wei XIE Xian-rong WANG Jun-bang LI Ying-nian huaNG Xiao-tao LI Hui-ting ZHOU hua-kun Key Laboratory of Adaptation and Evolution of Plateau Biota and Key Laboratory of Restoration Ecology in Cold Region of Qinghai Province Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Qinghai Haibei National Field Research Station of Alpine Grassland Ecosystem Xining 810008China Xi Ning Municipal Beishan Forestry Farm Xining 810003China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan ***,to date,the effects of long-term grazing exclusion measures on the process of restoring degraded alpine meadows have not been *** this study,moderately degraded plots,in which the vegetation coverage was approximately 65%and the dominant plant species was Potentilla anserina L,with grazing exclusion for 2 to 23 years,were selected in alpine meadows of Haibei in Qinghai-Tibet *** coverage,plant height,biomass,soil bulk density,saturated water content,soil organic carbon(SOC)and total nitrogen(TN)were *** results were as follows:(1)With aboveground biomass and total saturated water content at 0-40 cm depth,the average SOC and TN contents in moderately degraded alpine meadows increased as a power function,and the plant height increased as a log function.(2)The average soil bulk density at 0-40 cm depth first decreased and then increased with increasing grazing exclusion duration,and the minimum value of 0.90 g·cm^(-3) was reached at 15.23 *** plant coverage,total belowground biomass at 0-40 cm depth,total aboveground and belowground biomass first increased and then decreased,their maximum values(80.49%,2452.92g·m^(-2),2891.06 g·m^(-2))were reached at 9.41,9.46 and 10.25 years,***-term grazing exclusion is apparently harmful for the sustainable restoration of degraded alpine *** optimal duration of grazing exclusion for the restoration of moderately degraded alpine meadows was 10 *** research suggests that moderate disturbance should be allowed in moderately degraded alpine meadows after 10years of grazing exclusion.

关键词： Long-term grazing exclusion Soil water holdingcapacity Soilcarbonand nitrogen sequestration Biomass Alpine meadow

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A Quantum Secret Sharing Scheme Using Orbital Angular Momentum onto Multiple Spin States Based on Fibonacci Compression Encoding

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Communications in Theoretical Physics 2018年第10期70卷 384-390页

作者： Hong Lai Ming-Xing Luo yong-Jian Xu Josef Pieprzyk Jun Zhang lei Pan Mehmet A.Orgun School of Computer and Information Science and Centre for Research and Innovation in Software Engineering（RISE） Southwest UniversityChongqing 400715China Information Security and National Computing Grid Laboratory School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China Data61 Commonwealth Scientific and Industrial Research OrganisationSydneyAustralia Institute of Computer Science Polish Academy of SciencesWarsaw01-248Poland School of Software and Electrical Engineering Swinburne University of TechnologyHawthornVIC3122Australia School of Information Technology Deakin UniversityGeelongVIC3220Australia Department of Computing Macquarie UniversitySydneyNSW 2109Australia Faculty of Information Technology Macao University of Science and TechnologyAvenida Wai LongTaipa999078Macao

Since the use of a quantum channel is very expensive for transmitting large messages, it is vital to develop an effective quantum compression encoding scheme that is easy to implement. Given that, with the single-photon spin-orbit entanglement, we propose a quantum secret sharing scheme using orbital angular momentum onto multiple spin states based on Fibonacci compression encoding. In our proposed scheme, we can represent the frequency of any secret message which is typically collection of bits encodings of text or integers as a bitstring using the base Fibonacci sequence, which is encoded multiple spin states for secret shares transmitted to participants. We demonstrate that Fibonacci compression encoding carries excellent properties that enable us to achieve more robust quantum secret sharing schemes with fewer number of photons.

关键词： spin-orbit entanglement multiple spin states Fibonacci compression encoding quantum secretsharing

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阆中市华儿湾水库土石坝的设计和施工实践

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山西水利科技 2024年第1期 20-23,26页

作者：米仕勇四川南充水利电力建筑勘察设计研究院四川南充637000

因取材方便、能适应各种不同的地形地质气候条件等优点,土石坝成为实际工程中最为常用的一种坝型。综合技术经济比较后,阆中市华儿湾水库确定了合理的坝轴线和土石坝坝型。结合地形地质条件,前期设计中优化了坝体断面及分区。施工过程... 详细信息

因取材方便、能适应各种不同的地形地质气候条件等优点,土石坝成为实际工程中最为常用的一种坝型。综合技术经济比较后,阆中市华儿湾水库确定了合理的坝轴线和土石坝坝型。结合地形地质条件,前期设计中优化了坝体断面及分区。施工过程中处理了坝基地质缺陷、修正了坝壳料填筑指标,并初步探讨了坝基灌浆单位水泥耗量超定额的问题。

关键词：土石坝设计优化施工实践

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Clinical characteristics of remote Zeus robot-assisted laparoscopic cholecystectomy:A report of 40 cases

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World Journal of Gastroenterology 2006年第16期12卷 2606-2609页

作者： Han-Xin Zhou Yue-hua Guo Xiao-Fang Yu Shi-Yun Bao Jia-Lin Liu Yue Zhang yong-Gong Ren Qun Zheng Department of Minimal Invasive Surgery Shenzhen People's Hospital Jinan University 2^nd Clinical Medicine College Shenzhen 518020 Guangdong Province China Department of Anesthesia Shenzhen People's Hospital Jinan University 2^nd Clinical Medicine College Shenzhen 518020 Guangdong Province China Operation Room Shenzhen People's Hospital Jinan University 2^nd Clinical Medicine College Shenzhen 518020 Guangdong Province China

AIM： To summarize the performing essentials and analyze the characteristics of remote Zeus robot-assisted laparoscopic cholecystectomy. METHODS： Robot-assisted laparoscopic cholecystectomy was performed in 40 patients between May 2004 and July 2005. The operating procedures and a variety of clinical parameters were recorded and analyzed. RESULTS： Forty laparoscopic cholecystectomy procedures were successfully completed with Zeus robotic system. And there were no post-operative complications. Total operating time, system setup time and performing time were 100.3±18.5 min, 27.7±8.8 min and 65.6±18.3 min, respectively. The blood loss and postoperative hospital stay were 30.6±10.2 mL and 2.8±0.8 d, respectively. Camera clearing times and time used for operative field adjustment were 1.1±1.0 min and 2.0±0.8 rain, respectively. The operative error was 7.5%. CONCLUSION： Robot-assisted laparoscopic cholecystectomy following the principles of laparoscopic operation has specific performing essentials. It preserves the benefits of minimally invasive surgery and offers enhanced ability of controlling operation field, precise and stable operative manipulations.

关键词： Zeus Robotic surgical system Laparoscopic cholecystectomy

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Prolonged Viral Shedding in Three Young Adult Cases of COVID-19

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Infectious Diseases & Immunity 2022年第4期2卷 289-292页

作者： Wen-Yi Dong Ming-Ju Zhou lei huang Chao Zhang Fu-Sheng Wang Zhou-hua Xie Guangxi AIDS Clinical Treatment Centre The Fourth People’s Hospital of NanningNanning 530013China Beijing Ditan Hospital Capital Medical UniversityBeijing 100015China Medical Department of Infectious Diseases The Fifth Medical Centre of Chinese PLA General HospitalNational Clinical Research Centre for Infectious DiseasesBeijing 100039China

Severe acute respiratory syndrome coronavirus-2 infection is usually self-limited,with a short duration for viral shedding within several ***,prolonged viral shedding has been observed in severe or immune-compromised coronavirus disease 2019(COVID-19)***,we reported that three young adult cases of COVID-19 patients,who were either immunosuppressed nor severe,showed prolonged viral RNA shedding from the upper respiratory tract for 58,81,and 137 days since initial *** our knowledge,this is the longest duration of viral shedding reported to date in young adult *** studies on factors relevant to prolonged viral positivity,as well as the correlation between viral positivity and transmission risk are needed for the optimal management of COVID-19 patients with prolonged nucleic acid positive.

关键词： COVID-19 Immune-competent Prolonged viral shedding SAR-CoV-2

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Construction of Recombinant Modified Vaccinia Ankara(MVA) Expressing Hepatitis B Virus Surface Antigen

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Chemical Research in Chinese Universities 2006年第2期22卷 213-216页

作者： CHEN Yu YANG Xiao-song YU Xiang-hui JIANG Chun-lai WU yong-ge JIN Ying-hua CHEN Yue CHEN Yan LI Wei KONG Wei Vaccine Research Center College of Life Science Jilin University Changchun 130012 P. R. China

The T lymphocyte response has been shown to be the determinant in the clearance of many viral infections. Hence, therapeutic vaccine candidates against HBV are designed to enhance this response of the immune system. Vaccinia virus vector-based vaccines have been proposed as excellent candidates to elicit long-term and strong T lymphocyte mediated immune responses. In this study, the recombinant MVA expressing HBV surface antigen has been constructed, which can elicit a potent T cell mediated response. The ELISA results for the surface protein in the medium of the recombinant MVA, strongly indicate that the recombinant virus has been successfully obtained.

关键词： Recombinant MVA Therapeutic vaccine T lymphocyte response

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Cognitive Training in Older Adults with Mild Cognitive Impairment

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Biomedical and Environmental Sciences 2016年第5期29卷 356-364页

作者： LIU Xin Yan LI Li XIAO Jia Qing HE Chang Zhi LYU Xiu Lin GAO lei YANG Xiao Wei CUI Xin Gang FAN Li hua College of Public Health Harbin Medical University Harbin 150086 Heilongjiang China Heilongjiang Provincial Center for Disease Control and Prevention Harbin 150040 Heilongjiang China College of Management for the postgraduate Harbin Medical University Harbin 150086 Heilongjiang China Heilongjiang Provincial Hospital Harbin 150040 Heilongjiang China Department of Public Health Mudanjiang Medical College Mudanjiang 157000 Heilongjiang China

Objective We investigated the feasibility and efficacy of cognitive training for older adults in rura settings and with low education levels, who have mild cognitive impairment （MCl）. Methods Forty-five older adults （ages 〉65 years） with MCI were assigned to treatment or control groups, at a 2：1 ratio. Cognitive training occurred in the treatment group for 2 months. The cognitive abilities of the participants were assessed at pre-training, metaphase, and post-training time points, using the Mini-Mental State Examination （MMSE）, Montreal Cognitive Assessment （MoCA）, Loewenstein Occupational Therapy Cognitive Assessment （LOTCA）, and Hamilton Depression Scale （HAM-D）. Results Following training, cognitive abilities improved in the treatment group, based on the total scores of all 4 measures, as well as specifically on the MoCA and LOTCA. There were differences in the main effects of group and time point on some subscales, but these differences had little, if any, effect on the overall analyses. Conclusion The present study demonstrated that cognitive training has beneficial effects on attention, language, orientation, visual perception, organization of visual movement, and logical questioning in patients with MCI. Furthermore, the observed effects are long-term changes.

关键词： Older adults Rural Mild cognitive impairment Cognitive training Efficacy

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IMinpert:An Incomplete Minimum Perturbation Algorithm for Large Unsymmetric Linear Systems

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Numerical Mathematics A Journal of Chinese Universities(English Series) 2007年第4期16卷 300-312页

作者： lei Sun Xiaohong Wang yong Guan Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This paper gives the truncated version of the Minpert method:the incomplete minimum perturbation algorithm(IMinpert).It is based on an incomplete orthogonal- ization of the Krylov vectors in question,and gives a quasi-minimum backward error solution over the Krylov *** order to make the practical implementation of IMinpert easy and convenient,we give another approximate version of the IMinpert method:*** properties of the latter algorithm are ***- merical experiments are reported to show the proposed method is effective in practice and is competitive with the Minpert algorithm.

关键词：非对称性线性系统反差最小值干扰算法迭代法

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Expressions of Nucleoside Diphosphate Kinase (nm23) in Tumor Tissues are Related with Metastasis and Length of Survival of Patients with Hepatocellular Carcinoma

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Biomedical and Environmental Sciences 2010年第4期23卷 267-272页

作者： RUN AN JIE MENG QI SHI XIAO-XIA DAI JING-HONG CHEN YAN-JUN lei BING SHAN CHEN GAO yong-LIE CHU XIAO-PING DONG School of Medicine Xi'an Jiao-Tong University Xi'an 710061 Shanxi China State Key Laboratory for Infectious Disease Prevention and Control National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Ying-Xin Rd 100 Beijing 100052 China

Objective To evaluate the relationship of expressions of nucleoside diphosphate kinase （nm23） and proliferating cell nuclear antigen （PCNA）, as well as apoptosis, with the prognosis of HCC patients by analyzing their pathological and clinical data. Methods The expressions of nm23 and PCNA were analyzed by immunohistochemistry and the apoptotic phenomena were detected by TUNEL technique in the liver samples from 43 HCC tissues, 39 para-neoplastic tissues, and 10 normal tissues. The mean apoptosis index （AI） and proliferative index （PI） in individual sample were calculated. Results As shown by the detection, 32.6% of carcinomas had negative nm23 signal in tumor tissues, whereas all para-neoplastic and normal tissues had positive nm23. The AI in nm23 positive HCC was significantly higher than that in nm23 negative one, with statistical difference （P0.05）. Furthermore, the expressions of nm23, and the values of AI and PI were contrastively analyzed with some main pathological and clinical data of HCC. It revealed that HCC with extrahepatic metastasis showed remarkable correlation with the negative nm23 （P=0.013） and higher PI values of HCC （P=0.015）. The disease-free survival in HCC patients with negative nm23 expression was significantly poorer than that in patients with positive nm23 expression. Conclusion These data suggest that expressions of nm23 protein in tumor tissues are correlated with occurrences of metastasis and length of survival of the HCC patients, which may be an indicator for their prognosis.

关键词： Hepatocellular carcinoma nm23 PCNA Apoptosis Prognosis

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钛酸酯改性碳纳米管/聚氨酯复合材料的制备与性能

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热固性树脂 2024年第3期39卷 7-11页

作者：段华锋郭宁宁陈雅雯王磊贺浩王跃平山西科技学院山西晋城048000

采用Fenton试剂对多壁碳纳米管(MWCNTs)进行氧化处理,再利用异丙基三(二辛基焦磷酸酰氧基)钛酸酯(QX201)对WMCNTs进行接枝改性,并将改性的MWCNTs(MWCNTs-QX201)与聚氨酯(PU)混合制备复合材料。研究表明,QX201可有效改善MWCNTs与PU之间... 详细信息

采用Fenton试剂对多壁碳纳米管(MWCNTs)进行氧化处理,再利用异丙基三(二辛基焦磷酸酰氧基)钛酸酯(QX201)对WMCNTs进行接枝改性,并将改性的MWCNTs(MWCNTs-QX201)与聚氨酯(PU)混合制备复合材料。研究表明,QX201可有效改善MWCNTs与PU之间的相容性。当MWCNTs的用量为PU质量的1.5%时,MWCNTsQX201显著提高了复合材料的力学和热学性能,其中拉伸强度较纯MWCNTs/PU复合材料提升了25.5%,初始热分解温度以及最大热损失速率温度分别提高了6.4℃和3.1℃。

关键词：多壁碳纳米管钛酸酯偶联剂表面改性聚氨酯复合材料拉伸强度耐热性

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