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238篇 您的检索式:作者名="Zhang En"
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1On adjacent-vertex-distinguishing total coloring of graphs显示文摘In this paper, we present a new concept of the adjacent-vertex-distinguishing total coloring of graphs (briefly, AVDTC of graphs) and, meanwhile, have obtained the adjacent-vertex-distinguishing total chromatic number of some graphs such as cycle, complete graph, complete bipartite graph, fan, wheel and tree.ZHANG Zhongfu, CHEN Xiang’en, LI Jingwen, YAO Bing, LU Xinzhong & WANG Jianfang College of Mathematics and Information Science, Northwest Normal University, Lanzhou 730070, China Department of Computer, Lanzhou Normal College, Lanzhou 730070, China Institute of Applied Mathematics, Lanzhou Jiaotong University, Lanzhou 730070, China College of Information and Electrical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080, China 2005Science China Mathematics2005,48,3:173
2aunalysis of the Genome Sequence of the Medicinal Plant Salvia miltiorrhiza显示文摘Haibin Xu Jingyuan Song Hongmei Luo Yujun Zhang Qiushi Li Yingjie Zhu Jiang Xu Ying Li Chi Song Bo Wang Wei Sun Guoan Shen Xin Zhang Jun Qian Aijia Ji Zhichao Xu Xiang Luo Liu He Chuyuan Li Chao Sun Haixia Yah Guanghong Cui Xiwen Li Xian 'en Li Jianhe Wei Juyan Liu Yitao Wang Alice Hayward David Nelson Zemin Ning Reuben J. Peters Xiaoquan Qi Shilin Chen 2016Molecular Plant2016,9,6:70
3D(β)-vertex-distinguishing total coloring of graphs显示文摘A new concept of the D(β)-vertex-distinguishing total coloring of graphs, i.e., the proper total coloring such that any two vertices whose distance is not larger than β have different color sets, where the color set of a vertex is the set composed of all colors of the vertex and the edges incident to it, is proposed in this paper. The D(2)-vertex-distinguishing total colorings of some special graphs are discussed, meanwhile, a conjecture and an open problem are presented.ZHANG Zhongfu,LI Jingwen,CHEN Xiang’en,YAO Bing, WANG Wenjie & QIU Pengxiang Institute of Applied Mathematic, Lanzhou Jiaotong University, Lanzhou 730070, China College of Mathematics and Information Science, Northwest Normal University, Lanzhou 730070, China College of Information and Electrical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China 2006Science China Mathematics2006,49,10:54
4Detection of let-7a microRNA by real-time PCR in gastric carcinoma显示文摘AIM: To establish an accurate and rapid stem-loop reverse transcriptional real-time PCR (RT-PCR) method to quantify human let-7a miRNA in gastric cancer. METHODS: According to the sequence of let-7a miRNA,the stem-loop reverse transcriptional primer,the primers and quantitative MGB probes of real-time PCR were designed and synthesized. The dynamic range and the sensitivity of quantitative reverse transcriptional real-time PCR were determined. The levels of let-7a miRNA were examined in 32 gastric carcinoma samples by stem-loop RT-PCR method. RESULTS: The dynamic range and sensitivity of the let-7a miRNA quantification scheme were evaluated,the result showed the assay could precisely detect 10 copies of mature let-7a miRNA in as few as 0.05 ng of total RNA of gastric mucosa. The results of specificity analysis showed no fluorescence signal occurred even though 50 ng of human genomic DNA was added to the reverse transcription (RT) reaction. The expression level of let-7a miRNA in gastric tumor tissues was significantly lower compared to normal tissues in 14 samples from 32 patients. CONCLUSION: The stem-loop RT-PCR is a reliable method to detect let-7a miRNA which may play an important role in the development of gastric carcinoma.Hong-He Zhang Xian-Jun Wang Guo-Xiong Li En Yang Ning-Min Yang 2007World Journal of Gastroenterology2007,13,20:48
5Permian volcanisms in eastern and southeastern margins of the Jiamusi Massif, northeastern China: zircon U-Pb chronology, geochemistry and its tectonic implications显示文摘LA-ICP-MS zircon U-Pb dating and geochemical data for the Late Paleozoic volcanic rocks from eastern and southeastern margins of the Jiamusi Massif are presented to understand the regional tectonic evolution. Zircons from eight representative volcanic rocks are euhedral-subhedral in shape and dis- play striped absorption and fine-scale oscillatory growth zoning as well as high Th/U ratios (0.33―2.37), implying a magmatic origin. The dating results show that the Late Paleozoic volcanic rocks in the study area can be divided into two stages, i.e., the Early Permian (a weighted mean 206Pb/238U age of 288 Ma) and the Middle Permian volcanisms (a weighted mean 206Pb/238U age of 268 Ma). The former is com- posed mainly of basalt, basaltic-andesite, andesite and minor dacite. They are characterized by low SiO2 contents, high Mg# (0.40―0.59), enrichment in Na (Na2O/K2O = 1.26―4.25) and light rare earth elements (LREEs), relative depletion in heavy rare earth elements (HREEs) and high field strength ele- ments (HFSEs), indicating that an active continental margin setting could exist in the eastern margin of the Jiamusi Massif in the Early Permian. The latter consists mainly of rhyolite and minor dacite with high SiO2 (77.23%―77.52%), low MgO (0.11%―0.14%), enrichment in K2O (Na2O/K2O ratios < 0.80) and Rb, Th, U and depletion in Eu, Sr, P and Ti, implying a crust-derived origin. Therefore, it is proposed that the Middle Permian volcanic rocks could have formed under the collision of the Jiamusi and the Khanka Massifs.MENG En XU WenLiang YANG DeBin PEI FuPing Yu Yang Zhang XingZhou 2008Chinese Science Bulletin2008,53,8:42
6How many sutures in the southern Central Asian Orogenic Belt:Insights from East Xinjiang-West Gansu(NW China)?显示文摘How ophiolitic mèlanges can be defined as sutures is controversial with regard to accretionary orogenesis and continental growth.The Chinese Altay,East junggar,Tianshan,and Beishan belts of the southern Central Asian Orogenic Belt(CAOB) in Northwest China,offer a special natural laboratory to resolve this puzzle.In the Chinese Altay,the Erqis unit consists of ophiolitic melanges and coherent assemblages,forming a Paleozoic accretionary complex.At least two ophiolitic melanges(Armantai,and Kelameili) in East Junggar,characterized by imbricated ophiolitic melanges,Nb-enriched basalts,adakitic rocks and volcanic rocks,belong to a Devonian-Carboniferous intra-oceanic island arc with some Paleozoic ophiolites,superimposed by Permian arc volcanism.In the Tianshan,ophiolitic melanges like Kanggurtag,North Tianshan,and South Tianshan occur as part of some Paleozoic accretionary complexes related to amalgamation of arc terranes.In the Beishan there are also several ophiolitic melanges,including the Hongshishan,Xingxingxia-Shibangjing,Hongliuhe-Xichangjing,and Liuyuan ophiolitic units.Most ophiolitic melanges in the study area are characterized by ultramafic,mafic and other components,which are juxtaposed,or even emplaced as lenses and knockers in a matrix of some coherent units.The tectonic settings of various components are different,and some adjacent units in the same melange show contrasting different tectonic settings.The formation ages of these various components are in a wide spectrum,varying from Neoproterozoic to Permian.Therefore we cannot assume that these ophiolitic melanges always form in linear sutures as a result of the closure of specific oceans.Often the ophiolitic components formed either as the substrate of intra-oceanic arcs,or were accreted as lenses or knockers in subduction-accretion complexes.Using published age and paleogeographic constraints,we propose the presence of (1) a major early Paleozoic tectonic boundary that separates the Chinese Altay-East Junggar multiple subduction systems of the southern Siberian active margin from those of the northern Tarim;and (2) a major Permian suture zone that separates the Tianshan-Beishan from the northern active margin of the Tarim Craton.These new observations and interpretations have broad implications for the architecture and crustal growth of central Asia and other ancient orogens as well.Wenjiao Xiao Chunming Han Wei Liu Bo Wan Ji'en Zhang Songjian Ao Zhiyong Zhang Dongfang Song Zhonghua Tian Jun Luo 2014Geoscience Frontiers2014,5,4:31
7Indoor Allergen Levels and Household Distributions in Nine Cities Across China显示文摘Objective Chinese allergic subjects have high levels of sensitization to house dust mite(HDM) and other indoor allergens. This study quantifies common indoor allergen levels in Chinese households. Methods Dust samples were collected from nine cities. Major allergens Der p 1 and Der f 1 from Dermatophagoides pteronyssinus and D. farinae, and specific antigens of Blomia tropicalis, Tyrophagus putrescentiae, Acarus siro, and cockroach species Blattella germanica and Periplaneta americana were measured by ELISA. Results HDM allergens were found in dust samples from bedding in 95% of the Chinese households. The median levels varied from <0.006 to 9.2 μg/g of dust, depending on the city. The percentages of households having HDM allergen levels associated with the risk of developing allergy sensitization and asthma were 65% and 25%, respectively. Specific antigens of the storage mite and cockroach were only found in samples from the southern and tropical regions of China. Levels of mite allergens were generally higher in samples from bedding compared to samples from the living room, even for storage mites, whereas levels of cockroach antigens were higher in the living room samples. Conclusion HDM allergens are present in bedding dust samples from most Chinese households. Cities in southern and central China have relatively high levels of HDM major allergens compared to cities in northern and western China. Antigens of storage mites and cockroaches are not as common as HDM allergens.ZHENG Yi Wu LAI Xu Xin ZHAO De Yu ZHANG Chun Qing CHEN Jian Jun ZHANG Luo WEI Qing Yu CHEN Shi LIU En Mei NORBACK Dan GJESING Birgitte ZHONG Nan Shan SPANGFORT D.Michael 2015Biomedical and Environmental Sciences2015,28,10:24
8Flow Ripple of Axial Piston Pump with Computational Fluid Dynamic Simulation Using Compressible Hydraulic Oil显示文摘The flow ripple, which is the source of noise in an axial piston pump, is widely studied today with the computational fluid dynamic(CFD) technology development. In the traditional CFD modeling, the fluid compressibility, which strongly influences the accuracy of the flow ripple simulation results, is often neglected. So a compressible sub-model was added with user defined function(UDF) in the CFD model to predict the flow ripple. At the same time, a test rig of flow ripple was built to study the validity of simulation. The flow ripple of pump was tested with different working parameters, including the rotation speed and the working pressure. The comparisons with experimental results show that the validity of the CFD model with compressible hydraulic oil is acceptable in analyzing the flow ripple characteristics. In this paper, the improved CFD model increases the accuracy of flow ripple rate to about one-magnitude order. Therefore, the compressible model of hydraulic oil is necessary in the flow ripple investigation of CFD simulation. The compressibility of hydraulic oil has significant effect on flow ripple, and the compression ripple takes about 88% of the total flow ripple of pump. Leakage ripple has the lowest proportion of about 4%, and geometrical ripple leakage ripple takes the remnant 8%. Besides, the influence of working parameters was investigated through the CFD simulations and experimental measurements. Comparison results show that the amplitude of flow ripple grows with the increasing of rotation speed and working pressure, and the flow ripple rate is independent of the rotation speed. However, flow ripple rate of piston pump grows with the increasing of working pressure, because the leakage ripple will increase with the pressure growing. The investigation on flow ripple of an axial piston pump using compressible hydraulic oil provides a more validity simulation model for the CFD analyzing and is beneficial to further understanding of the flow ripple characteristics in an axial piston pump.MA Ji'en XU Bing ZHANG Bin YANG Huayong 2010Chinese Journal of Mechanical Engineering2010,23,1:21
9Anatomy of composition and nature of plate convergence: Insights for alternative thoughts for terminal India-Eurasia collision显示文摘The pattern and timing of collision between India and Eurasia have long been a major concern of the international community. However, no consensus has been reached hitherto. To explore and resolve the disagreements in the Himalayan study,in this paper we begin with the methodology and basic principles for the anatomy of composition and nature of convergent margins,then followed by an effort to conduct a similar anatomy for the India-Eurasia collision. One of the most common patterns of plate convergence involves a passive continental margin, an active continental margin and intra-oceanic basins together with accreted terranes in between. The ultimate configuration and location of the terminal suture zone are controlled by the basal surface of the accretionary wedge, which may show fairly complex morphology with Z-shape and fluctuant geometry. One plausible method to determine the terminal suture zone is to dissect the compositions and structures of active continental margins. It requires a focus on various tectonic elements belonging to the upper plate, such as accretionary wedges, high-pressure(HP)-ultra-high-pressure(UHP) metamorphic rocks, Barrovian-type metamorphic rocks and basement nappes, together with superimposed forearc basins.Such geological records can define the extreme limits and the intervening surface separating active margin from the passive one,thus offering a general sketch for the surface trace of the terminal suture zone often with a cryptic feature. Furthermore, the occurrence of the cryptic suture zone in depth may be constrained by geophysical data, which, in combination with outcrop studies of HP-UHP metamorphic rocks, enables us to outline the terminal suture zone. The southern part of the Himalayan orogen records complicated temporal and spatial features, which are hard to be fully explained by the classic 'two-plate-one-ocean' template,therefore re-anatomy of the compositions and nature for this region is necessitated. Taking advantage of the methodology and basic principles of plate convergence anatomy and synthesizing previous studies together with our recent research, we may gain new insights into the evolution of the Himalayan orogeny.(1) The Yarlung-Zangbo ophiolite is composed of multiple tectonic units rather than a single terminal suture zone, and a group of different tectonic units were juxtaposed against each other in the backstop of the Gangdese forearc.(2) The Tethyan Himalayan Sequence(THS) contains mélanges with typical block-in-matrix structures, uniform southwards paleocurrents and age spectra of detrital zircons typical of Eurasia continent. All of these facts indicate that the THS belonged to Eurasia plate before the terminal collision, emplaced in the forearc of the Gangdese arc.(3) The Greater Himalayan Crystalline Complex(GHC) and Lesser Himalayan Sequence(LHS) comprise complex components including eclogites emplaced into the GHC and the upper part of the LHS. Judging from the fact that HP-UHP metamorphic rocks are exhumed and emplaced in the upper plate, the GHC and the upper part of the LHS where eclogite occur should be assigned to the upper plate, lying above the terminal subduction zone surface. It is the very surface along which the continuous subduction of the India subcontinent occurred, therefore acting as the terminal, cryptic suture. From the suture further southward, the bulk rock associations of the LHS and Sub-Himalayan Sequence(Siwalik) show little affinity of mélange, probably belonging to the foreland system of the India plate. By the anatomy of tectonic features of all the tectonic units in the Himalayan orogen as well as the ages of the subduction-accretion related deformation, we conclude that the terminal India-Eurasia collision occurred after 14 Ma, the timing of the metamorphism of the eclogites emplaced into the upper plate. The development of rifts stretching in N-S direction in Tibet and tectonic events with the transition from sinistral to dextral movements in shear zones, such as the Ailaoshan fault in East Tibet, can coordinately reflect the scale and geodynamic influence of the India-Eurasia convergence zone.By conducting a detailed anatomy of the southern Himalayas, we propose a new model for the final collision-accretion of the Himalayan orogeny. Our study indicates that the anatomy of structures, composition, and tectonic nature is the key to a better understanding of orogenic belts, which may apply to all the orogenic belts around the world. We also point out that several important issues regarding the detailed anatomy of the structures, compositions and tectonic nature of the Himalayan orogeny in future.XIAO WenJiao AO SongJian YANG Lei HAN ChunMing WAN Bo ZHANG Ji'En ZHANG ZhiYong LI Rui CHEN ZhenYu SONG ShuaiHua 2017Science China Earth Sciences2017,60,6:20
10T cell–associated immunoregulation and antiviral effect of oxymatrine in hydrodynamic injection HBV mouse model显示文摘Although oxymatrine(OMT) has been shown to directly inhibit the replication of hepatitis B virus(HBV) in vitro, limited research has been done with this drug in vivo. In the present study, the antiviral effect of OMT was investigated in an immunocompetent mouse model of chronic HBV infection.The infection was achieved by tail vein injection of a large volume of DNA solution. OMT(2.2, 6.7 and20 mg/kg) was administered by daily intraperitoneal injection for 6 weeks. The efficacy of OMT was evaluated by the levels of HBV DNA, hepatitis B surface antigen(HBs Ag), hepatitis B e antigen(HBe Ag)and hepatitis B core antigen(HBc Ag). The immunoregulatory activity of OMT was evaluated by serum ELISA and flow cytometry. Results shows that OMT at 20 mg/kg inhibited HBV replication, and it was more efficient than entecavir(ETV) in the elimination of serum HBs Ag and intrahepatic HBc Ag. Inaddition, OMT accelerated the production of interferon-γ(IFN-γ) in a dose-dependent manner in CD4^+T cells. Our findings demonstrate the beneficial effects of OMT on the enhancement of immunological function and in the control of HBV antigens. The findings suggest this drug to be a good antiviral therapeutic candidate for the treatment of HBV infection.Xiuxiu Sang Ruilin Wang Yanzhong Han Cong’en Zhang Honghui Shen Zhirui Yang Yin Xiong Huimin Liu Shijing Liu Ruisheng Li Ruichuang Yang Jiabo Wang Xuejun Wang Zhaofang Bai Xiaohe Xiao 2017Acta Pharmaceutica Sinica B2017,7,3:20
11Accretionary processes and metallogenesis of the Central Asian Orogenic Belt:Advances and perspectives显示文摘As one of the largest Phanerozoic orogens in the world,the Central Asian Orogenic Belt(CAOB)is a natural laboratory for studies of continental dynamics and metallogenesis.This paper summarizes the research progresses of the accretionary processes and metallogenesis of the CAOB since the Peopled Republic of China was founded,and puts forward the prospect for future research.During the early period(1950s-1970s),several geological theories were applied to explain the geological evolution of Central Asia.In the early period of China's reform and opening-up,the plate tectonics theory was applied to explain the evolution of the northern Xinjiang and Xingmeng regions,and the opinion of subduction-collision between Siberian Kazakhstan and China-North Korea-Tarim plates was proposed.The idea of the Solonker-Yanbian suture zone was established.In the 1990s,the study of the CAOB entered a period of rapid development.One school of scholars including geologists from the former Soviet Union proposed a multi-block collision model for the assemblage of the CAOB.In contrast,another school of scholars,led by a Turkish geologist,Celal Sengor,proposed that the Altaids was formed through the growth and strike-slip duplicates of a single island arc,and pointed out that the Altaids is a special type of collisional orogen.During this period,Chinese geologists carried out a lot of pioneering researches on ophiolites and high-pressure metamorphic rocks in northern China,and confirmed the main suture zones accordingly.In 1999,the concept of'Central Asian metallogenic domain'was proposed,and it became one of the three major metallogenic domains in the world.Since the 21st century,given the importance for understanding continental accretion and metallogenic mechanism,the CAOB has become the international academic forefront.China has laid out a series of scientific research projects in Central Asia.A large number of important scientific research achievements have been spawned,including the tectonic attribution of micro-continents,timing and tectonic settings of ophiolites,magmatic arcs,identification and anatomy of accretionary wedges,regional metamorphism-deformation,(ultra)high-pressure metamorphism,ridge subduction plume-plate interaction archipelagic paleogeography and spatio-temporal framework of multiple accretionary orogeny,continental growth accretionary metallogenesis,structural superposition and transformation etc.These achievements have made important international influences.There still exist the following aspects that need further study:(1)Early evolution history and subduction initiation of the Paleo-Asian Ocean;(2)The accretionary mechanism of the extroversion Paleo-Asian Ocean;(3)The properties of the mantle of the Paleo-Asian Ocean and their spatiotemporal distribution;(4)The interaction between the Paleo-Asian Ocean and the Tethys Ocean;(5)Phanerozoic continental growth mechanism and its global comparison;(6)Accretionary metallogenic mechanism of the Central Asian metallogenic domain;and(7)Continental transformation mechanism.Wenjiao XIAO Dongfang SONG Brian FWINDLEY Jiliang LI Chunming HAN Bo WAN Ji'en ZHANG Songjian AO Zhiyong ZHANG 2020Science China Earth Sciences2020,63,3:16
12Selective inhibition of Hepatocarcinoma cells by apatite nanoparticles显示文摘The effects of HAP nanoparticles on growth of primary normal animal liver cells and on growth of hepatocarcinoma cell line Bel 7402 in vitro were studied respectively and were compared with each other.The results showed that HAP nanoparticles in certain concentration inhibited growth of cancer cells significantly while did not inhibite normal cells in the same concentration.The inhibition ratio was as high as very high dosage of adriamycin.It was concluded that HAP nanoparticles can selectively inhibited cancer cells.SUN En jie 1, LI Shi pu 2 ,YAN Yu hua 2 CAO Xian ying 2,FENG Ling yun 2 , XIONG Xian li 2,ZHANG Zhu 2 1 College of Materials Science and Engineering 2 Biomedical Materials And Engineering Center Wuhan University of Science and Technol 2002Chinese Journal of Biomedical Engineering(English Edition)2002,11,2:10
13Pediculate Brachiopod Diandongia pista from the Lower Cambrian of South China显示文摘The Chengjiang Lagerstatte has been celebrated for prolific soft-bodied fossils. Based on specimens recentlyexcavated in the Chengjiang Lagerstatte by the Early Life Institute, Northwest University, Diandongiapista Rong, 1974, isdirectly revealed to be a pediculate brachiopod, assigned to the Family Botsfordiidae, as is further confirmed by theexceptionally preserved vascular system including dorsal and ventral mantle canals. These specimens described hereinexhibit some peculiarities, notably the extremely thin and long pedicles, which suggest that Diandongia is epifaunal ratherthan burrowing brachiopod. A study of this group of animals indicates that they may be vital to understand the relationshipbetween the lingulids and the remaining brachiopods, and the character evolution of the early Cambrian brachiopods.ZHANG Zhifei, HAN Jian, ZHANG Xingliang, LIU Jianni and SHU DeganEarly Life Institute and Key Laboratory for Continental Dynamics of the Ministry of Education,Northwest University, Xi’an, Shaanxi 710069 E-mail: zhangelle@sina.com.cn Wang Si’en and Xie Guanglian 2003Acta Geologica Sinica(English Edition)2003,77,3:9
14Rice-duck co-culture benefits grain 2-acetyl-1-pyrroline accumulation and quality and yield enhancement of fragrant rice显示文摘Rice-duck co-culture is an integrated farming technology that benefits rice production, grain quality, and ecological sustainability in paddy fields. However, little is known about the effects of rice-duck co-culture on enzyme activity involved in the biosynthesis of 2-acetyl-1-pyrroline (2-AP), the volatile that gives fragrant rice its' distinctive and sought-after aroma. The present study aimed to examine the influence of rice-duck co-culture on the photosynthesis, yield, grain quality, rice aroma, and the enzymes involved in 2-acetyl-1-pyrroline biosynthesis in the cultivar Meixiangzhan 2 during the early and late rice growing seasons of 2016 in Guangzhou, China. We compared the rice grown in paddy fields with and without ducks. We found that rice-duck co-culture not only improved the yield and quality of fragrant rice grain, but also promoted the precursors of 2-AP biosynthesis formation and 2-AP accumulation in the grain. Grain 2-AP content in rice-duck co-culture was noticeably increased with 9.60% and 20.81% in early and late seasons, respectively. Proline and pyrroline-5-carboxylic acid (P5C) (precursors of 2-AP biosynthesis) and the activity of enzymes such as proline dehydrogenase (ProDH), ornithine aminotransferase (OAT) and Δ1 pyrroline-5-carboxylic acid synthetase (P5CS) were all improved by 10.15%–12.99%, 32.91%–47.75%, 17.81%–26.71%, 6.25%–21.78%, and 10.58%–38.87% under rice-duck co-culture in both seasons, respectively. Overall, our results suggest that rice-duck co-culture is an environmentally-friendly and sustainable approach to improving rice aroma and grain quality of fragrant rice.Meijuan Li Ronghua Li Shiwei Liu Jia'en Zhang Hao Luo Shuqing Qiu 2019The Crop Journal2019,7,4:8
15Measuring Recreational Value of World Heritage Sites Based on Contingent Valuation Method:A Case Study of Jiuzhaigou显示文摘World heritage possesses various kinds of use value and non-use value. Measuring the recreational value of world heritage sites is a key issue in the heritage tourism. This paper employs Contingent Valuation Method (CVM), which is an evaluation instrument on the basis of tourists′ attitude and preference, to measure the recreational value of Jiuzhaigou, one of the World Natural Heritage sites in China, and analyzes the biases in the survey. The results show that: 1) In 2009, Jiuzhaigou′s recreational value was 3.46×108 yuan (RMB), and the per capita Willingness to Pay (WTP) was 137.31 yuan by CVM. Compared with the results of other methods, this result is significantly low. 2) Among the factors that influence Jiuzhaigou tourists′ WTP, psychological perception factors have the greatest effect while demographic and socio-economic characteristics have a small effect on WTP. 3) The virtuality in CVM creates biases both from CVM itself and in the procedures that CVM was implemented. The former includes hypothetical bias, information bias, protest response bias, and strategic bias; and the latter includes the questionnaire design, population and sample definition, sampling and data processing. The paper analyses those biases and illustrates their potential in-fluences on the accuracy of CVM measurement. 4) Although there are various defects in CVM measurement, it is still an effective valuation method.DONG Xuewang ZHANG Jie ZHI Ruizhi ZHONG Shi'en LI Min 2011Chinese Geographical Science2011,21,1:8
16Development and Validation of a Model for Predicting Diabetic Nephropathy in Chinese People显示文摘Objective To develop a risk model for predicting later development of diabetic nephropathy(DN)in Chinese people with type 2 diabetes mellitus(T2DM)and evaluate its performance with independent validation.Methods We used data collected from the project‘Comprehensive Research on the Prevention and Control of Diabetes’,which was a community-based study conducted by the Jiangsu Center for Disease Control and Prevention in 2013.A total of 11,771 eligible participants were included in our study.The endpoint was a clear diagnosis of DN.Data was divided into two components:a training set for model development and a test set for validation.The Cox proportional hazard regression was used for survival analysis in men and women.The model’s performance was evaluated by discrimination and calibration.Results The incidence(cases per 10,000 person-years)of DN was 9.95(95%CI;8.66-11.43)in women and 11.28(95%CI;9.77-13.03)in men.Factors including diagnosis age,location,body mass index,high-density-lipoprotein cholesterol,creatinine,hypertension,dyslipidemia,retinopathy,diet control,and physical activity were significant in the final model.The model showed high discrimination and good calibration.Conclusion The risk model for predicting DN in people with T2DM can be used in clinical practice for improving the quality of risk management and intervention.MIAO Dan Dan PAN En Chun ZHANG Qin SUN Zhong Ming QIN Yu WU Ming 2017Biomedical and Environmental Sciences2017,30,2:8
17Medicine in Future and Advantages of Integrated Chinese and Western Medicine显示文摘The history of medical development shows that oriental medicine, or traditional medicine, was born through medical practice during the times when science and technology were immature and underdeveloped, whereas with the development of science and technology, Western medicine, or modern medicine, was born through experimental analysis and research. With the development of medicine, the pros and cons of both medical systems become increasingly evident. How to integrate them and learn from each other will be the direction of future development of medicine. The formation and development of integrated medicine will, inevitably, usher in a new era for medicine.ZHANG Jiang-hua WU Mi-shan WANG Yue-fen JIA Ying-min LI En 2019Chinese Journal of Integrative Medicine2019,25,2:7
18Capilliposide from Lysimachia capillipes inhibits AKT activation and restores gefitinib sensitivity in human non-small cell lung cancer cells with acquired gefitinib resistance显示文摘有非小的房间肺癌症(NSCLC ) 的最对待 gefitinib 的病人将最后开发抵抗。从 LC Hemsl 的 Lysimachia capillipes (LC ) capilliposide 摘录。在 vitro 并且在 vivo 反癌症效果出现。在这研究,我们调查了在有 gefitinib 的联合的 LC capilliposide 是否能克服 NSCLC 房间的抵抗到 gefitinib 并且识别包含的发信号的小径。有 LC capilliposide 的治疗独自禁止了 NSCLC 房间线(PC-9, H460, H1975, H1299 和 PC-9-GR ) 的一块面板的生长对有在 g/mL 的范围的 IC 50 价值的 gefitinib 敏感或抵抗。在 gefitinib 抵抗的 PC-9-GR 房间(它有一个 T790M EGFR 变化) , LC capilliposide (在 IC30, i.e.1.2 g/mL ) 显著地与它的 IC50 价值提高了 gefitinib 的禁止的效果从 6.80Shi-rong ZHANG Ya-si XU Er JIN Lu-cheng ZHU Bing XIA Xu-feng CH EN Fan-zhu LI Sheng-lin MA 2017Acta Pharmacologica Sinica2017,38,1:7
19Anisotropic optical and electronic properties of two- dimensional layered germanium sulfide显示文摘二维(2D ) 分层的材料,转变金属 dichalcogenides,和黑磷从基本物理和设备应用的观点吸引了可观的兴趣。在各向异性的分层的 2D 材料的新功能的建立是挑战性却令人满意的边疆,由于为新设备的这些材料和他们的前景的显著光性质。此处,我们报导各向异性并且厚度依赖者 2D 的光性质金者硫化物(GeS ) 的分层的 monochalcogenide。相应于 B 3g, 的三座散布 Raman 山峰 g 1 ,和 有强壮的极化依赖的 g 2 模式在 GeS 薄片被表明,它为识别各向异性的分层的 GeS 的水晶取向作为一个有效方法验证极化的拉曼光谱学。光致发光(PL ) 在 ~ 与一座山峰被观察在房间温度在 GeS 从直接光的转变发源的 1.66 eV。PL 的极化依赖者特征,第一次被揭示,在 GeS 的乐队边附近显示明显的各向异性的光转变,它被密度支持功能的理论计算。显著地,厚度依赖者 PL 被观察并且讨论。这各向异性的分层的 GeS 为新物理现象和愿望的发现介绍机会发现利用它的各向异性的性质的应用,例如极化敏感的光电探测器。Dezhi Tan Hong En Lim Feijiu Wang Nur Baizura Mohamed Shinichiro Mouri Wenjin Zhang Yuhei Miyauchi Mari Ohfuchi Kazunari Matsuda 2017Nano Research2017,10,2:7
20Investigation of maximum proton energy for qualified ground based evaluation of single-event effects in SRAM devices显示文摘Existing standards show a clear discrepancy in the specification of the maximum proton energy for qualified ground-based evaluation of single-event effects,which can range from 180 to 500 MeV. This work finds that the threshold linear energy transfer of a tested device is a critical parameter for determining the maximum proton energy. The inner mechanisms are further revealed. Highenergy deposition events(>10 MeV) in sensitive volumes are attributed to the interaction between protons and the tungsten vias in the metallization layers.Zhan-Gang Zhang Yun Huang Yun-Fei En Zhi-Feng Lei 2019Nuclear Science and Techniques2019,30,3:6
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