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329篇 您的检索式:作者名="Yanfeng ZHANG"
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1Contrasting trends of PM2.5 and surface-ozone concentrations in China from 2013 to 2017显示文摘Although much attention has been paid to investigating and controlling air pollution in China,the trends of air-pollutant concentrations on a national scale have remained unclear.Here,we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017,during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions.Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China,with an annual decrease of〜7%compared with measurements in 2013.The measured decreased concentrations of SO2>NO2 and CO(a proxy for anthropogenic volatile organic compounds)could explain a large fraction of the decreased PM2.5 concentrations in different regions.As a consequence;the heavily polluted days decreased significantly in corresponding regions.Concentrations of organic aerosol;nitrate;sulfate,ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017;connecting the decreases in aerosol precursors with corresponding chemical components closely.However;surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017;which indicates stronger photochemical pollution.The boundary-layer height in capital c让ies of eastern China showed no significant trends over the Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta regions from 2013 to 2017;which confirmed the reduction in anthropogenic emissions.Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017,although the ozone concentration has increased significantly;suggesting a more complex mechanism of improving Chinese air quality in the future.Yonghong Wang Wenkang Gao Shuai Wang Tao Song Zhengyu Gong Dongsheng Ji Lili Wang Zirui Liu Guiqian Tang Yanfeng Huo Shili Tian Jiayun Li Mingge Li Yuan Yang Biwu Chu Tuukka Petaja Veli-Matti Kerminen Hong He Jiming Hao Markku Kulmala Yuesi Wang Yuanhang Zhang 2020National Science Review2020,7,8:51
2Ginkgo biloba extract improved cognitive and neurological functions of acute ischaemic stroke:a randomised controlled trial显示文摘Purpose To evaluate the efficacy and safety of Ginkgo biloba extract(GBE)in acute ischaemic stroke and its impact on the recurrence of vascular events.Methods We conducted a multicentre,prospective,randomised,open label,blinded,controlled clinical trial enrollingpatients with an onset of acute stroke within 7 days from five hospitals in China Jiangsu Province.Participants were assigned to the GBE group(450 mg GBE with 100 mg aspirin daily)or the control group(100 mg aspirin daily)for 6 months.The primary outcome was the decline in the Montreal Cognitive Assessment score at 6 months.Secondary outcomes were other neuropsychological tests of cognitive and neurological function,the the incidence of adverse events and vascular events.results 348 patients were enrolled:179 in the GBE group and 169 in the control group.With 18 patients lost to follow-up,the dropout rate was 5.17%.Admission data between two groups were similar,but in the GBE group there was a marked slow down in the decline in the Montreal Cognitive Assessment scores(−2.77±0.21 vs−1.99±0.23,P=0.0116(30 days);−3.34±0.24 vs−2.48±0.26,P=0.0165(90 days);−4.00±0.26 vs−2.71±0.26,P=0.0004(180 days))compared with controls.The National Institutes of Health Stroke Scale scores at 12 and 30 days,the modified Rankin Scale scores for independent rate at 30,90 and 180 days,and the Barthel Index scores at 30,90 and 180 days in the GBE group were significantly improved compared with controls.Improvements were also observedin GBE groups for Mini-Metal State Examination scores of 30,90 and 180 days,Webster's digit symbol test scores at 30 days and Executive Dysfunction Index scores at 30 and 180 days.No significant differences were seen in the incidence of adverse events or vascular events.conclusions We conclude that GBE in combination with aspirin treatment alleviated cognitive and neurological deficits after acute ischaemic stroke without increasing the incidence of vascular events.Shanshan Li Xinjiang Zhang Qi Fang Junshan Zhou Meijuan Zhang Hui Wang Yan Chen Biyun Xu Yanfeng Wu Lai Qian Yun Xu 2017Stroke & Vascular Neurology2017,2,4:25
3Whole-genome sequencing of 508 patients identifies key molecular features associated with poor prognosis in esophageal squamous cell carcinoma显示文摘Esophageal squamous cell carcinoma(ESCC)is a poor-prognosis cancer type with limited understanding of its molecular etiology.Using 508 ESCC genomes,we identified five novel significantly mutated genes and uncovered mutational signature clusters associated with metastasis and patients’outcomes.Several functional assays implicated that NFE2L2 may act as a tumor suppressor in ESCC and that mutations in NFE2L2 probably impaired its tumor-suppressive function,or even conferred oncogenic activities.Additionally,we found that the NFE2L2 mutations were significantly associated with worse prognosis of ESCC.We also identified potential noncoding driver mutations including hotspot mutations in the promoter region of SLC35E2 that were correlated with worse survival.Approximately 5.9%and 15.2%of patients had high tumor mutation burden or actionable mutations,respectively,and may benefit from immunotherapy or targeted therapies.We found clinically relevant coding and noncoding genomic alterations and revealed three major subtypes that robustly predicted patients’outcomes.Collectively,we report the largest dataset of genomic profiling of ESCC useful for developing ESCC-specific biomarkers for diagnosis and treatment.Yongping Cui Hongyan Chen Ruibin Xi Heyang Cui Yahui Zhao Enwei Xu Ting Yan Xiaomei Lu Furong Huang Pengzhou Kong Yang Li Xiaolin Zhu Jiawei Wang Wenjie Zhu Jie Wang Yanchun Ma Yong Zhou Shiping Guo Ling Zhang Yiqian Liu Bin Wang Yanfeng Xi Ruifang Sun Xiao Yu Yuanfang Zhai Fang Wang Jian Yang Bin Yang Caixia Cheng Jing Liu Bin Song Hongyi Li Yi Wang Yingchun Zhang Xiaolong Cheng Qimin Zhan Yanhong Li Zhihua Liu-Show 2020Cell Research2020,30,10:19
4Mesozoic-Cenozoic Multi-Stage Intraplate Deformation Events in the Langshan Region and their Tectonic Implications显示文摘In the Langshan region, northwestern China, marked multi-stage intraplate deformation events have occurred since the Mesozoic, including(1) northeast-striking ductile left-lateral strike slip during the Middle-Late Triassic, which is closely related to the collision between the North China and the Yangtze plates;(2) top-to-the-southeast thrust with northwest-southeast trending maximum compression during the Late Jurassic;(3) nearly eastward detachment during the Early Cretaceous;(4) top-to-the-northwest thrust with northwest-southeast trending maximum compression during the Late Cretaceous and Early Cenozoic;(5) northeast-striking brittle left-lateral strike slip with nearly north-south trending maximum compression; and(6) northwest-southeast extension during the Middle-Late Cenozoic. All these deformation events belong to the intraplate deformation across the entire Central Asian region and respond to the tectonic events along the plate boundaries or deep tectonics. The structures developed in early events in the crust were the most important factors controlling the later deformation styles, and few new structures have later developed. Based on previous research and our results, the paleostress inversion in the Langshan region shows that the Mesozoic intraplate deformations in the study region mainly resulted from the tectonic events from the Paleo-Pacific region and have no or a weak relation to the Tethys region. During the Late Jurassic, the maximum compression from the Mongolia-Okhotsk region cannot be excluded. The Langshan region is the bridge between southern Mongolia and the western Ordos tectonic belt and is thus important to understand the nature and relationship between both regions.ZHANG Jin LI Jinyi LI Yanfeng QI Wenhua ZHANG Yiping 2014Acta Geologica Sinica(English Edition)2014,88,1:18
5Hidden policy ciphertext-policy attribute-based encryption with keyword search against keyword guessing attack显示文摘Attribute-based encryption with keyword search(ABKS) enables data owners to grant their search capabilities to other users by enforcing an access control policy over the outsourced encrypted data. However,existing ABKS schemes cannot guarantee the privacy of the access structures, which may contain some sensitive private information. Furthermore, resulting from the exposure of the access structures, ABKS schemes are susceptible to an off-line keyword guessing attack if the keyword space has a polynomial size. To solve these problems, we propose a novel primitive named hidden policy ciphertext-policy attribute-based encryption with keyword search(HP-CPABKS). With our primitive, the data user is unable to search on encrypted data and learn any information about the access structure if his/her attribute credentials cannot satisfy the access control policy specified by the data owner. We present a rigorous selective security analysis of the proposed HP-CPABKS scheme, which simultaneously keeps the indistinguishability of the keywords and the access structures. Finally,the performance evaluation verifies that our proposed scheme is efficient and practical.Shuo QIU Jiqiang LIU Yanfeng SHI Rui ZHANG 2017Science China(Information Sciences)2017,60,5:18
6Toxicities and risk assessment of heavy metals in sediments of Taihu Lake, China, based on sediment quality guidelines显示文摘The occurrence, toxicities, and ecological risks of five heavy metals(Pb, Cu, Cd, Zn and Ni) in the sediment of Taihu Lake were investigated in this study. To evaluate the toxicities caused by the heavy metals, the toxicities induced by organic contaminants and ammonia in the sediments were screened out with activated carbon and zeolite. The toxicities of heavy metals in sediments were tested with benthic invertebrates(tubificid and chironomid).The correlations between toxicity of sediment and the sediment quality guidelines(SQGs)derived previously were evaluated. There were significant correlations(p < 0.0001) between the observed toxicities and the total risk quotients of the heavy metals based on SQGs,indicating that threshold effect level(TEL) and probable effect level(PEL) were reliable to predict the toxicities of heavy metals in the sediments of Taihu Lake. By contrast, the method based on acid volatile sulfides(AVS) and simultaneously extracted metals(SEM),such as ∑SEM/AVS and ∑SEM-AVS, did not show correlations with the toxicities. Moreover,the predictive ability of SQGs was confirmed by a total predicting accuracy of 77%. Ecological risk assessment based on TELs and PELs showed that the contaminations of Pb, Cu, Cd and Zn in the sediments of Taihu Lake were at relatively low or medium levels. The risks caused by heavy metals in the sediments of northern bay of the lake, which received more wastewater discharge from upper stream, were higher than other area of the lake.Yanfeng Zhang Yuwei Han Jinxi Yang Lingyan Zhu Wenjue Zhong 2017Journal of Environmental Sciences2017,29,12:16
7Development of land use transitions research in China显示文摘With the introduction of the concept of land use transition into China,related researches have been carried out extensively in the past two decades,which enrich the knowledge of land system science.This paper describes the development of research on land use transitions in China from the perspectives of conceptual connotations,theoretical model,research methods,and research progress and prospects.With the in-depth investigation of land use transitions,the concept and connotations of land use morphology are developed and encapsulated as two kinds,i.e.,dominant morphology and recessive morphology.The dominant morphology refers to the land use structure of a certain region over a certain period of time,with features such as the quantity and spatial pattern of land use types.While the recessive morphology includes the land use features in the aspects of quality,property rights,management mode,input,output and function.Accordingly,the concept of land use transition is further developed,and the theoretical model of regional land use transitions is established.Thereafter,three innovative integrated approaches to study land use transitions are put forward,i.e.,multidisciplinary research framework for recessive land use transition,transect and horizontal comparison.To date,there have been 62 Ph.D.and 166 M.S.dissertations on the topic of'land use transition'in China.During 2002–2019,the National Natural Science Foundation of China has funded 48 research programs on the theme of'land use transition'.As such,the Chinese scholars have adapted the concept derived from western literature to the situations and experiences in China.LONG Hualou QU Yi TU Shuangshuang ZHANG Yingnan JIANG Yanfeng 2020Journal of Geographical Sciences2020,30,7:15
8Effects of culm carbohydrate partitioning on basal stem strength in a high-yielding rice population显示文摘Rice culm carbohydrate transport can simultaneously affect grain filling and stem lodging resistance by regulating non-structural carbohydrate(NSC) and structural carbohydrate(SC) contents. However, the relationship between carbohydrate transposition and culm strength is not well documented. Accordingly, a high-yielding hybrid rice cultivar(Y Liangyou 2) was tested under different N fertilization regimes at two locations, Taoyuan(a special high-yield eco-site), Yunnan province and Danyang(a representative eco-site of the middle and lower Yangtze), Jiangsu province, China. Significantly higher grain yield and basal stem strength were found at Taoyuan than Danyang under all N rates throughout the two-year experiment. At heading stage, soluble sugars, starch, cellulose and lignin contents of the basal culm at Taoyuan were significantly 132.0%, 73.7%, 1.2%, and 62.7% higher than those at Danyang, respectively. At 20 days after heading, soluble sugars and starch content at Taoyuan decreased significantly compared to Danyang, but lignin content remained higher. Culm carbohydrate transport to kernels at Taoyuan was significantly greater than that at Danyang, and the proportion of soluble sugars and starch was correspondingly 62.9%lower. However, the proportion of lignin and cellulose was 22.7% higher at Taoyuan than that at Danyang. Soluble sugars and starch partitioning were significantly reduced under an increased nitrogen application rate, but SC partitioning was little affected. There were significant positive correlations between basal culm bending stress and dry weight and cellulose and lignin proportions at both locations under all N rates, suggesting that the higher SC proportion at 20 days after heading was primarily responsible for culm strength.These results suggest that high-yielding rice populations with greater culm strength require both moderate NSC transport and greater SC accumulation.Jun Zhang Ganghua Li Qingyu Huang Zhenghui Liu Chengqiang Ding She Tang Lin Chen Shaohua Wang Yanfeng Ding Weijian Zhang 2017The Crop Journal2017,5,6:13
9Direct low-temperature synthesis of graphene on various glasses by plasma-enhanced chemical vapor deposition for versatile, cost-effective electrodes显示文摘在低温度的各种各样的玻璃底层上的 graphene 的没有催化剂、可伸缩的合成具有到象便宜透明电子学和最先进的显示器那样的众多的应用程序的首要的意义。然而,在这个有希望的研究领域以内的系统的学习远这样仍然保持少见。此处,我们用一个低温度的提高血浆的化学蒸汽免职方法在各种各样的眼镜上报导 graphene 的直接生长。如此的一条灵巧、可伸缩的途径在 400600 的一个生长温度范围在各种各样的玻璃底层上保证一致、没有转移的 grapheneJingyu Sun Yubin Chen Xin Cai Bangjun Ma Zhaolong Chen Manish Kr. Priydarshi Ke Chen Teng Gao Xiuju Song Qingqing Ji Xuefeng Guo Dechun Zou Yanfeng Zhang Zhongfan Liu 2015Nano Research2015,8,11:12
10Chemical vapor deposition growth of large-scale hexagonal boron nitride with controllable orientation显示文摘有一致厚度的大域的六角形的硼氮化物(h-BN ) 的化学蒸汽免职(CVD ) 合成是很挑战性的,主要由于这材料的极其高的成核密度。此处,我们报导晶片规模的成功的生长,有大单人赛水晶的领域尺寸的高质量的 h-BN 单层电影,吗直到~ 72 ??????????????????????????慮潮档湡敮獬???????慮潮畴敢??洠獥灯牯????  ??Xiuju Song Junfeng Gao Yufeng Nie Teng Gao Jingyu Sun Donglin Ma Qiucheng Li Yubin Chen Chuanhong Jin Alicja Bachmatiuk Mark H. Rummeli Feng Ding Yanfeng Zhang Zhongfan Liu 2015Nano Research2015,8,10:12
11A new approach based on PSO algorithm to find good computational encoding sequences显示文摘Computational encoding DNA sequence design is one of the most important steps in molecular computation. A lot of research work has been done to design reliable sequence library. A revised method based on the support system developed by Tanaka et al. is proposed here with different criteria to construct fitness function. Then we adapt particle swarm optimization (PSO) algorithm to our encoding problem. By using the new algorithm, a set of sequences with good quality is generated. The result also shows that our PSO-based approach could rapidly converge at the minimum level for an output of the simulation model. The celerity of the algorithm fits our requirements.Cui Guangzhao Niu Yunyun Wang Yanfeng Zhang Xuncai Pan Linqiang 2007Progress in Natural Science:Materials International2007,17,6:11
12Late Mesozoic-Cenozoic Exhumation of the Northern Hexi Corridor:Constrained by Apatite Fission Track Ages of the Longshoushan显示文摘The apatite fission track(AFT) ages and thermal modeling of the Longshoushan and deformation along the northern Hexi Corridor on the northern side of the Qinghai-Tibetan Plateau show that the Longshoushan along the northern corridor had experienced important multi-stage exhumations during the Late Mesozoic and Cenozoic. The AFT ages of 7 samples range from 31.9 Ma to 111.8 Ma.Thermal modeling of the AFT ages of the samples shows that the Longshoushan experienced significant exhumation during the Late Cretaceous to the Early Cenozoic(-130-25 Ma). The Late Cretaceous exhumation of the Longshoushan may have resulted from the continuous compression between the Lhasa and Qiangtang blocks and the flat slab subduction of the Neo-Tethys oceanic plate, which affected wide regions across the Qinghai-Tibetan Plateau. During the Early Cenozoic, the Longshoushan still experienced exhumation, but this process was caused by the Indian-Eurasian collision. Since this time,the Longshoushan was in a stable stage for approximately 20 Ma and experienced erosion. Since ~5 Ma,obvious tectonic deformation occurred along the entire northern Hexi Corridor, which has also been reported from the peripheral regions of the Qinghai-Tibetan Plateau, especially in the Qilianshan and northeastern margin of the plateau. The AFT ages and the Late Cenozoic deformation of the northern Hexi Corridor all indicate that the present northern boundary of the Qinghai-Tibetan Plateau is situated along the northern Hexi Corridor.ZHANG Beihang ZHANG Jin WANG Yannan ZHAO Heng LI Yanfeng 2017Acta Geologica Sinica(English Edition)2017,91,5:11
13Arithmetic computation using self-assembly of DNA tiles:subtraction and division显示文摘Recently, experiments have demonstrated that simple binary arithmetic and logical operations can be computed by the process of self- assembly of DNA tiles. In this paper, we show how the tile assembly process can be used for subtraction and division. In order to achieve this aim, four systems, including the comparator system, the duplicator system, the subtraction system, and the division system, are pro- posed to compute the difference and quotient of two input numbers using the tile assembly model. This work indicates that these systems can be carried out in polynomial time with optimal O(1) distinct tile types in parallel and at very low cost. Furthermore, we provide a scheme to factor the product of two prime numbers, and it is a breakthrough in basic biological operations using a molecular computer by self-assembly.Xuncai Zhang Yanfeng Wang Zhihua Chen Jin Xu Guangzhao Cui 2009Progress in Natural Science:Materials International2009,19,3:10
14Expression and subcellular localization of mechano-growth factor in osteoblasts under mechanical stretch显示文摘Mechano-growth factor (MGF) is a stretch sensitive factor in myocytes, and it might also be produced by other mechanocytes under mechanical stimulation. In this study, both the mRNA and protein expression of MGF were detected in stretched osteoblasts. Quantitative analysis showed that a cyclic stretching stimulation caused a quick and sharp increase of MGF mRNA and protein expression from a low basal level under no stretch; the mRNA and protein levels respectively peaked in 6 and 12 h to 5 and 5.2 fold over the basal level and returned to normal by 24 h. The subcellular distribution of MGF protein was revealed by immunofluorescence analysis to be restricted to the nucleus. We concluded that cyclic stretching stimulation could induce MGF expression in osteoblasts in a pulsing fashion; and the nuclear distribution of MGF suggested that MGF might act in mechanocytes as an autocrine growth factor.ZHANG BingBing, XIAN ChengYu, LUO YanFeng & WANG YuanLiang Research Center of Bioinspired Materials Science and Engineering, Bioengineering College, Chongqing University, Chongqing 400030, China 2009Science China(Life Sciences)2009,52,10:10
15Modified PSO algorithm for solving planar graph coloring problem显示文摘The graph coloring is a classic NP-complete problem. Presently there is no effective method to solve this problem. Here we propose a modifled particle swarm optimization (PSO) algorithm in which a disturbance factor is added to a particle swarm optimizer for improv- ing its performance. When the current global best solution cannot be updated in a certain time period that is longer than the disturbance factor, a certain number of particles will be chosen according to probability and their velocities will be reset to force the particle swarm to get rid of local minimizers. It is found that this operation is helpful to improve the performance of particle swarm. Classic planar graph coloring problem is resolved by using modifled particle swarm optimization algorithm. Numerical simulation results show that the per- formance of the modified PSO is superior to that of the classical PSO.Guangzhao Cui Limin Qin Sha Liu Yanfeng Wang Xuncai Zhang Xianghong Cao 2008Progress in Natural Science:Materials International2008,18,3:9
16Terahertz spoof surface-plasmon-polariton subwavelength waveguide显示文摘Surface plasmon polaritons(SPPs) with the features of subwavelength confinement and strong enhancements have sparked enormous interest. However, in the terahertz regime, due to the perfect conductivities of most metals, it is hard to realize the strong confinement of SPPs, even though the propagation loss could be sufficiently low. One main approach to circumvent this problem is to exploit spoof SPPs, which are expected to exhibit useful subwavelength confinement and relative low propagation loss at terahertz frequencies. Here we report the design,fabrication, and characterization of terahertz spoof SPP waveguides based on corrugated metal surfaces. The various waveguide components, including a straight waveguide, an S-bend waveguide, a Y-splitter, and a directional coupler, were experimentally demonstrated using scanning near-field terahertz microscopy. The proposed waveguide indeed enables propagation, bending, splitting, and coupling of terahertz SPPs and thus paves a new way for the development of flexible and compact plasmonic circuits operating at terahertz frequencies.YING ZHANG YUEHONG XU CHUNXIU TIAN QUAN XU XUEQIAN ZHANG YANFENG LI XIXIANG ZHANG JIAGUANG HAN WEILI ZHANG 2018Photonics Research2018,9,1:9
17Designing N-doped graphene/ReSe_(2)/Ti_(3)C_(2) MXene heterostructure frameworks as promising anodes for high-rate potassium-ion batteries显示文摘Developing high-performance anodes for potassium ion batteries(KIBs) is of paramount significance but remains challenging.In the normal sense,electrode materials are prepared by ubiquitous wet chemical routes,which otherwise might not be versatile enough to create desired heterostructures and/or form clean interfacial areas for fast transport of K-ions and electrons.Along this line,rate capability/cycling stability of resulting KIBs are greatly handicapped.Herein we present an all-chemical vapor deposition approach to harness the direct synthesis of nitrogen-doped graphene(NG)/rhenium diselenide(ReSe_2)hybrids over three-dimensional MXene supports as superior heterostructure anode material for KIBs.In such an innovative design,1 T'-ReSe2 nanoparticles are sandwiched in between the NG coatings and MXene frameworks via strong interfacial interactions,thereby affording facile K~+ diffusion,enhancing overall conductivity,boosting high-power performance and reinforcing structural stability of electrodes.Thus-constructed anode delivers an excellent rate performance of 138 mAh g^(-1) at 10.0 A g^(-1) and a high reversible capacity of 90 mAh g^(-1) at 5 A g^(-1) after 300 cycles.Furthermore,the potassium storage mechanism has been systematically probed by advanced in situlex situ characterization techniques in combination with first principles computations.Zhou Xia Xiwen Chen Haina Cia Zhaodi Fan Yuyang Yi Wanjian Yin Nan Wei Jingsheng Cai Yanfeng Zhang Jingyu Sun 2021Journal of Energy Chemistry2021,30,2:9
18Spatio-temporal patterns of drought in North Xinjiang, China, 1961–2012 based on meteorological drought index显示文摘Drought, which is one of the most frequently occurring severe hazards with long time scales and covering wide geographical areas, is a natural phenomenon resulting in significant economic losses in agriculture and industry. Drought is caused by an imbalance between the inputs of and the demand for water which is insufficient to meet the demands of human activities and the eco-environment. As a major arid and semi-arid area and an important agricultural region in Northwest China, North Xinjiang(NX) shows great vulnerability to drought. In this paper, the characteristics of inter-annual and seasonal drought were analyzed in terms of drought occurrence and drought coverage, by using the composite index of meteorological drought and the data of daily precipitation, air temperature, wind speed, relative humidity and sunshine duration from 38 meteorological stations during the period 1961–2012. Trend analysis, wavelet analysis and empirical orthogonal function were also applied to investigate change trend, period and regional characteristics, respectively. In NX, annual and seasonal drought occurrence and drought coverage all showed a decreasing trend that was most significant in winter(with rates of –0.26 month/10 a and –15.46%, respectively), and drought occurrence in spring and summer were more frequent than that in autumn and winter. Spatially, drought was severe in eastern regions but mild in western regions of NX. Annual and seasonal drought occurrence at 38 meteorological stations displayed decreasing trends and were most significant in 'Shihezi-Urumqi-Changji', which can help to alleviate severe drought hazards for local agricultural production and improve human livelihood. NX can be approximately classified into three sub-regions(severe drought region, moderate drought region and mild drought region), which were calculated from annual drought frequencies. The cross wavelet transform suggested that SOI(Southern Oscillation Index), AOI(Arctic Oscillation Index), AAOI(Antarctic Oscillation Index), PAOI(Pacific/North American Oscillation Index) and NAOI(North Atlantic Oscillation Index) have significant correlation with the variation of drought occurrence in NX. To prevent and mitigate the occurrence of drought disasters in NX, agricultural and government managers should pay more attention to those drought events that occur in spring and summer.WU Yanfeng Batur BAKE ZHANG Jusong Hamid RASULOV 2015Journal of Arid Land2015,7,4:8
19Efficient and Large-Scale Synthesis of Few-Layered Graphene Using an Arc-Discharge Method and Conductivity Studies of the Resulting Films显示文摘An arc-discharge method using a buffer gas containing carbon dioxide has been developed for the efficient and large-scale synthesis of few-layered graphene.The resulting samples of few-layered graphene,well-dispersed in organic solvents such as N,N-dimethylformamide(DMF)and 1,2-dichlorobenzene(o-DCB),were examined by transmission electron microscopy(TEM),X-ray diffraction(XRD),Raman spectroscopy,atomic force microscopy(AFM),and thermal gravimetric analysis(TGA).The electrical conductivity and transparency of flexible films prepared using a direct solution process have also been studied.Yingpeng Wu Bin Wang Yanfeng Ma Yi Huang Na Li Fan Zhang Yongsheng Chen 2010Nano Research2010,3,9:8
20Alternative splicing and expression of the insulin-like growth factor (IGF-1) gene in osteoblasts under mechanical stretch显示文摘(IGF-1 ) 像胰岛素的生长因素 1 支持造骨细胞区别和骨头形成,和它的表示被机械段导致,因此, IGF-1 被认为连接机械刺激和本地织物回答的一个受动器分子。在这研究,一台机械拉长设备被设计把生理的水平静电干扰或周期的拉长刺激用于造骨细胞。IGF-1 mRNA 的不同 isoforms 被 RT-PCR 用各自的教材从房间放大,这些放大产品被定序。产品被发现被造骨细胞有选择地在拉长刺激下面生产的拼接的 IGF-1 的 iso 形式。ThisIGF-1 isoform 与原来在肌肉细胞被识别的 mechano 生长因素(MGF ) 有相同顺序。肝类型 IGF (L.IGF-1 ) 和在在段刺激下面的造骨细胞的 MGF 的表示的规定进一步用半量的 RT-PCR 被学习。Stretchstimulation 被发现 IGF-1 (L.IGF-1 和 MGF ) 的表示到职业人员警句,并且为两 isoformsexpression,更多被周期的段有效地比静态的段刺激。MGF 仅仅在受到机械段的造骨细胞被检测,建议 MGF 是段敏感生长因素。MGF 的表示比 L.IGF-1 的早达到顶点,它类似于他们在肌肉的规定并且作为在肌肉房间在骨头建议了 MGF 和 L.IGF-1 的类似的角色。在造骨细胞的 MGF 和 L.IGF-1 的功能将被进一步试验性的研究建立。XIAN Chengyu WANG Yuanliang ZHANG Bingbing TANG Liling PAN Jun LUO Yanfeng JIANG Peng LI Dajun 2006Chinese Science Bulletin2006,51,22:7
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