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Characterization of Ser73 in Arabidopsis thaliana Glutathione S-transferase zeta class

Journal of Genetics and Genomics 2008年第8期35卷 507-512页

作者： Sudan Tao Xiwen Chen jia liu ming ming Namsu Chong Defu Chen Laboratory of Molecular Genetics College of Life Sciences Nankai University Tianjin 300071 China

Glutathione S-transferases （GSTs） are ubiquitous detoxifying superfamily enzymes. The zeta class GST from Arabidopsis thaliana （AtGSTZ） can efficiently degrade dichloroacetic acid （DCA）, which is a common carcinogenic contaminant in drinking water. Ser73 in AtGSTZ is a conserved residue at Glutathione binding site （G-site）. Compared with the equivalent residues in other GSTs, the catalytic and structural properties of Ser73 were poorly investigated. In this article, site-saturation mutagenesis was performed to characterize the detailed role of Ser73. The DCA dechlorinating （DCA-DC） activity showed that most of the mutants had less than 3% of the wild-type activity, except S73T and S73A showing 43.48% and 21.62% of the wild-type activity, respectively, indicating that position 73 in AtGSTZ showed low mutational substitutability. Kinetic experiments revealed that mutants S73T, S73A, and S73G showed low binding affinity and catalytic efficiency toward DCA, 1.8-, 3.1-, and 10.7- fold increases in KmDcA values and 4.0-, 9.6-, and 34.1- fold decreases in Kcat- DCA/KmDCA values, respectively, compared to the wild type. Thermostability and refolding experiments showed that the wild type mainmined more thermostability and recovered activity. These results demonstrated the important role of Ser73 in catalytic activity and structural stability of the enzyme. Such properties of Ser73 could be particularly crucial to the molecular evolution of AtGSTZ and might, therefore, help explain why Ser73 is conserved in all GSTs. This conclusion might provide insights into the directed evolution of the DCA-DC activity of AtGSTZ.

关键词： Set73 thermostability refolding ability site-saturation mutagenesis ArGSTZ

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Tourism sectorization opportunity spectrum model and space partition of tourism urbanization area:a case of the Mayangxi ecotourism area,Fujian province,China

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Journal of Mountain Science 2017年第3期14卷 595-608页

作者： TAO Hui liu jia-ming DENG Yu DU Ao Institute of Geographic Sciences andNatural Resources Research ChineseAcademy of ScienceBeijing 100101China Institute of economics and management Hubei University for NationalitiesEnShi 445000China University of Chinese Academy of Sciences Beijing 100049China

Nowadays, tourism has become an increasingly significant driving force of modern urbanization in China. However, it has caused varieties of problems, such as resource unreasonable utilization, society unfair play, and environment pollution, etc. Thus, the establishment of an efficient and sustainable space partition model for tourism urbanization, from the geographical perspective, is highly necessary and urgent. Herein, a new evaluation model of tourist town space, referred to as Tourism Sectorization Opportunity Spectrum(TSOS), is established on the relationships between productionliving-ecology spaces. TSOS is a kind of quantitative evaluation model involving such factors as urban living area, ecological conservation area and the tourism industry. Furthermore, the analysis of quantitative production-living-ecology spatial overlap has been utilized for space division in a tourism urbanization area. This paper, using both the TSOS model and GIS technology, analyzes the spatial restructure of the Mayangxi ecotourism area. Theresult demonstrates that tourism industrial space takes the Shanchong Village as a core which shows a pattern of local regional agglomeration and a fuzzy edge extending along the entire Mayangxi River. The urban living area should be consolidated in the Shili village with the supporting facilities and living space for tourism. In addition, Tianzhu Mountain forest park should be the key environmental protection area. The case study on the Mayangxi ecotourism area verifies that the TSOS model has strong operability. Therefore, TSOS model provides a scientific foundation for the space reconstruction of new urbanization area, and an effective tool for optimizing the space partition of a tourism urbanization area.

关键词： Tourism urbanization Sectorization Space reconstruction Tourism sectorization Opportunity spectrum Mayangxi ecotourism area

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Spatial Differentiation of Tourism Impact Based on the Perception of Residents in Mountainous Valley Resorts

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Journal of Mountain Science 2014年第4期11卷 1070-1084页

作者： LI Shan-shi liu jia-ming WANG Run ZHU He Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Valley economy is a type of economy that comprehensively utilizes the natural economic and social resources of the region based on environmental protection. This economy utilizes the basic role of the market in disposing resources and achieving regional development and social progress. In this paper we studied the town of Yanqi, a valley resort that has developed tourism-based valley economy for several years in the mountainous area of Beijing. This research identifies the spatial differentiation of tourism-related economic, socio-cultural, and environmental impact and level of support for tourism according to the perception and attitude of residents of Yanqi. The research area was divided into three zones(i.e., core, transition, and peripheral)according to the standard proposed by Jaakson. The residents in all three zones showed a positive attitude toward the tourism industry, and the residents in the core zone had a stronger perception toward the impact of tourism. However, several items indicated the converse. Correlation analysis and analysis of variance were used to explore the correlative factors associated with the attitudes of residents toward the tourism industry. Results indicated major differences among the three zones. Multiple factors, including natural conditions, policies, scenic spots, dependence on the tourism industry, and external investment in the three zones resulted in the spatial differentiation of the perception and attitude of residents toward the impact of tourism.

关键词： Valley economy Resident perception Tourism impact Yanqi Driving factor

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Tourism resource assessment and spatial analysis of wine tourism development： a case study of the eastern foothills of China＇s Helan Mountains

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Journal of Mountain Science 2018年第3期15卷 645-656页

作者： WANG Lei liu jia-ming WANG Ling-en ZHU He LIN Jing Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China College of Humanities Ningxia University Yinchuan 750021 China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

The reasonable development and utilization of mountainous regions closely relates to local economic development and ecological security. The wine production region in the eastern foothills of the Helan Mountains in Ningxia, Ningxia Hui Autonomous Region, with its excellent terroir, is emerging as one of China's three major geographical attractions. Based on surveys of tourism resources and spatial analysis for this wine producing region, we propose a highly representative and practicable path for wine tourism development. Based on China's national standard in Classification, Investigation and Evaluation of Tourism Resources(GB/T 18972-2003), which recommended the types and grades of tourism resources in one area, we conduct an analysis of resource characteristics and the current state of development. Using Arc GIS software, spatialautocorrelation analysis, average nearest neighbor analysis, as well as clustering and outlier analysis, we are able to derive the spatial distribution characteristics of tourism resources. Our survey showed that tourism resources in this area are relatively abundant and have good quality and clear combination advantages. Nonetheless, there are resources shortage for wine tourism and poor integration of wine production with the tourism industry. Regarding the spatial distribution of resources, we revealed the current states of and issues surrounding regions with concentrated resources, as well as characteristics of this clustering. Finally, we proposed a development path for wine tourism in this region based on the five dimensions of management mode, industrial path, product development, spatial optimization, and market development.

关键词： Development path Helan Mountains Resource assessment Wine tourism

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Investigating the tourism image of mountain scenic spots in China through the lens of tourist perception

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Journal of Mountain Science 2023年第8期20卷 2298-2314页

作者： LI Feng-jiao LIAO Xia liu jia-ming jiaNG Li-li WANG Meng-di liu Jin-feng Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Geography Science Harbin Normal UniversityHarbin 150025China School of Foreign Language and Tourism Wuxi PolytechnicWuxi 214121China

A favorable tourism image of high-quality mountain scenic spots(HQMSS)is crucial for tourism prosperity and *** paper establishes a framework for investigating the tourism image based on cognitive-emotion theory and uses natural language processing(NLP)tools to clarify the cognition,emotion,and overall tourist image of the HQMSS in China from the perspective of tourist *** paper examines the multi-dimensional spatial differentiation of China's overall image,including province,scenic spot scales,as well as the spatial pattern of the overall comprehensive tourism *** for comprehensively improving HQMSS's tourism image are also *** results show that:(1)The cognitive image of Chinese HQMSS is categorized into core and marginal images,and the core images such as scenery and cable car are the expression of the uniqueness of mountainous scenic ***,the cognitive image is classified into six dimensions:tourism environment,tourism supporting facilities,tourism experience,tourism price,tourism service,and tourism safety.(2)Positive emotions are the dominant mood type of HQMSS in China,followed by neutral emotions,with negative emotions being the least *** images vary across dimensions,with tourism environment and tourism experience evoking relatively higher emotion.(3)The spatial pattern of HQMSS for each dimension at the national,provincial,and scenic scales is *** article provides a multidimensional perspective for investigating the tourism image of mountainous scenic spots,proposes targeted recommendations to improve the overall image of HQMSS in China,and can greatly contribute to the sustainable development of mountain tourism.

关键词： Mountain scenic spot Tourism image Spatial differentiation Natural language processing Cognitive-emotion theory Tourist perception

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RESID HYDROCONVERSION—A NEW APPROACH IN PROCESSING INFERIOR RESIDUAL OILS

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石油学报（石油加工） 2001年第1期17卷 35-41页

作者： LI Zhi qiang, liu jia ming, SUN Li li (Beijing Design Institute, SINOPEC, Beijing 100724, China) 中国石油化工公司北京设计所北京 100724 中国石油化工总公司北京设计所北京 100724

In order to meet the market demands for more premium distillates and the more stringent requirements of environment protection, China refineries should find a better way for deep processing of residues. This paper describes the necessity, overview and application of the resid hydroconversion process in China. Qilu Petrochemical Co. built the first vacuum resid hydrodesulfurization (VRDS) unit with a capacity of 840 kt/a of Gudao vacuum residue in 1986. And Dalian West Pacific Petrochemical Co. Ltd. built the first atmospheric resid hydrodesulfurization (ARDS) unit with the capacity of 2 Mt/a in 1992. Beijing Design Institute SINOPEC did the engineering design of these two units. Some modifications on the units were carried out, which gives the adaptability and flexibility in processing inferior crudes such as high sulfur crudes.

关键词：加氢裂化残油市场需求环境保护

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Measurement of Cross Sections for the ^(10)B(n,α)^(7)Li Reaction at 4.0 and 5.0MeV Using an Asymmetrical Twin Gridded Ionization Chamber

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Chinese Physics Letters 2011年第8期28卷 61-64页

作者： ZHANG Guo-Hui liu Xiang liu jia-ming XUE Zhi-Hua WU Hao CHEN Jin-Xiang State Key Laboratory of Nuclear Physics and Technology Institute of Heavy Ion PhysicsSchool of PhysicsPeking UniversityBeijing 100871

Cross sections of the 10B(n,α)7Li reaction(including the total,the“leaking”alpha,forward alpha and backward alpha parts)at En=4.0 and 5.0 MeV were measured using an asymmetrical twin gridded ionization chamber and two back−to-back 10B *** were performed at the 4.5 MV Van de Graaff accelerator of Peking *** neutrons were produced through the ^(2)H(d,n)3He reaction with a deuterium gas *** neutron flux was determined by a ^(238)U sample set inside the gridded ionization chamber and a BF_(3) long counter was employed as a neutron flux monitor and for *** present results are compared with previous measurements and evaluations.

关键词： backward asymmetrical

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Grape Seed Proanthocyanidin Extract Alleviates Arsenic-induced Oxidative Reproductive Toxicity in Male Mice

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Biomedical and Environmental Sciences 2015年第4期28卷 272-280页

作者： LI Shu Gang DING Yu Song NIU Qiang XU Shang Zhi PANG Li Juan MA Ru Lin JING ming Xia FENG Gang Ling liu jia ming GUO Shu Xia Department of Public Health and Key Laboratory of Xinjiang Endemic and Ethnic Diseases (Ministry of Education) Shihezi University School of Medicine

Objective To determine the ability of grape seed proanthocyanidin extract （GSPE） in alleviating arsenic-induced reproductive toxicity. Methods Sixty male Kunming mice received the following treatments by gavage： normal saline solution （control）; arsenic trioxide （ATO; 4 mg/kg）; GSPE （400 mg/kg）; ATO＋GSPE （100 mg/kg）; ATO＋GSPE （200 mg/kg） and ATO＋GSPE （400 mg/kg）. Thereafter, the mice were sacrificed and weighed, and the testis was examined for pathological changes. Nuclear factor （erythroid-derived 2）-like 2 （Nrf2）, heme oxygenase 1 （HO1）, glutathione S-transferase （GST）, NAD（P）H dehydrogenase, and quinone 1 [NQO1） expression in the testis was detected by real-time PCR. Superoxide dismutase （SOD）, glutathione （GSH）, total antioxidative capability （T-AOC）, malondialdehyde （MDA）, 8-hydroxydeoxyguanosine （8-OHdG）, and reproductive indexes were analyzed. Results ATO-treated mice showed a significantly decreased sperm count and testis somatic index and activity levels of SOD, GSH, and T-AOC than control group. Compared to the ATO-treated group, ATO ＋GSPE group showed recovery of the measured parameters. Mice treated with ATO＋high-dose GSPE showed the highest level of mRNA expression of Nrf2, HO, NO.O1, and GST. Conclusion GSPE alleviates oxidative stress damage in mouse testis by activating Nrf2 signaling, thus counteracting arsenic-induced reproductive toxicity.

关键词： Grape seed proanthocyanidin extract Arsenic Reproductive toxicity Nrf2 signaling

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人力资源拍卖:实证与应用展望

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人口与经济 2010年第4期 31-36页

作者：刘家明嘉应学院政法学院广东梅州514015

笔者通过调查、回顾人力资源拍卖的多起实践活动,实证归纳了人力资源拍卖的理论内涵,总结了与人力资源拍卖的定义及相近概念的特征与实质,构建了人力资源拍卖实施的过程模型,探讨了人力资源拍卖在现实中实施应具备的各种条件和适合于应... 详细信息

笔者通过调查、回顾人力资源拍卖的多起实践活动,实证归纳了人力资源拍卖的理论内涵,总结了与人力资源拍卖的定义及相近概念的特征与实质,构建了人力资源拍卖实施的过程模型,探讨了人力资源拍卖在现实中实施应具备的各种条件和适合于应用的范围。

关键词：人力资源人力资源拍卖人才拍卖人力资源市场化

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Comparison of Clinical Characteristics and Outcomes of Pediatric and Adult Patients with Coronavirus Disease 2019 in Shenzhen,China

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Biomedical and Environmental Sciences 2020年第12期33卷 906-915页

作者： WANG Fang LAI Chang Xiang HUANG Peng Yu liu jia ming WANG Xian Feng TANG Qi Yuan ZHOU Xuan XIAN Wen Jie CHEN Rui Kun LI Xuan LI Zhi Yu LIAO Li Qun HE Qing liu Lei National Clinical Research Center for Infectious Disease Shenzhen Third People's HospitalDepartment of HepatologySecond Hospital Affiliated to Southern University of Science and TechnologyShenzhen 518112GuangdongChina Fujian Provincial Reproductive Medicine Center Fujian Maternity and Children's Hospital Affiliated to Fujian Medical UniversityFuzhou 350001FujianChina Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of Hepatopancreatobiliary Surgery IPeking University Cancer Hospital&InstituteBeijing 100142China

Objective Here we aimed to investigate the difference in clinical characteristics and outcomes between pediatric and adult patients with *** A total of 333 consecutive patients with laboratory-confirmed SARS-CoV-2 infection treated in the departments of Internal medicine of Shenzhen Third People’s Hospital from January 11 th to February 10 th,2020 were *** data were obtained from electronic medical *** epidemiological data,clinical characteristics,length of hospital stays,and outcomes of pediatric and adult patients were *** Compared with adult patients,pediatric patients had a shorter time of symptom onset to hospitalization than adults[median time,1(IQR,1.0-1.0)d vs.3(IQR,2.0-6.0)d,P<0.001],milder or fewer symptoms,less severe chest CT *** clinical severity classification of children was less severe than *** to 15 th March,the end of the follow-up,33(100%)children and 292(97.3%)adult patients had been discharged from *** 2(0.7%)adult patients died,with an overall case mortality of 0.6%.The median length of hospital stay of pediatric patients was shorter than that of adult patients[19(95%CI:16.6-21.4)d vs.21(95%CI:19.9-22.1)d,P=0.024].Conclusion Pediatric patients with COVID-19 had milder or less clinical symptoms,less evident pulmonary imaging changes,better prognosis,and shorter length of hospital stay.

关键词： Coronavirus disease 2019 Severe acute respiratory syndrome coronavirus 2 Clinical characteristics Pediatric patients

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