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1Relative Contributions of Boundary-Layer Meteorological Factors to the Explosive Growth of PM2.5 during the Red-Alert Heavy Pollution Episodes in Beijing in December 2016显示文摘Based on observations of urban mass concentration of fine particulate matter smaller than 2.5 μm in diameter(PM_(2.5)), ground meteorological data, vertical measurements of winds, temperature, and relative humidity(RH), and ECMWF reanalysis data, the major changes in the vertical structures of meteorological factors in the boundary layer(BL) during the heavy aerosol pollution episodes(HPEs) that occurred in winter 2016 in the urban Beijing area were analyzed. The HPEs are divided into two stages: the transport of pollutants under prevailing southerly winds, known as the transport stage(TS), and the PM_(2.5) explosive growth and pollution accumulation period characterized by a temperature inversion with low winds and high RH in the lower BL, known as the cumulative stage(CS). During the TS, a surface high lies south of Beijing, and pollutants are transported northwards. During the CS, a stable BL forms and is characterized by weak winds, temperature inversion, and moisture accumulation. Stable atmospheric stratification featured with light/calm winds and accumulated moisture(RH > 80%) below 250 m at the beginning of the CS is closely associated with the inversion, which is strengthened by the considerable decrease in near-surface air temperature due to the interaction between aerosols and radiation after the aerosol pollution occurs. A significant increase in the PLAM(Parameter Linking Aerosol Pollution and Meteorological Elements) index is found, which is linearly related to PM mass change. During the first 10 h of the CS, the more stable BL contributes approximately 84% of the explosive growth of PM_(2.5) mass. Additional accumulated near-surface moisture caused by the ground temperature decrease, weak turbulent diffusion, low BL height, and inhibited vertical mixing of water vapor is conducive to the secondary aerosol formation through chemical reactions, including liquid phase and heterogeneous reactions, which further increases the PM_(2.5) concentration levels. The contribution of these reaction mechanisms to the explosive growth of PM_(2.5) mass during the early CS and subsequent pollution accumulation requires further investigation.junting zhong xiaoye zhang yaqiang wang junying sun yangmei zhang jizhi wang kaiyan tan xiaojing shen haochi che lu zhang zhouxiang zhang xuefei qi huarong zhao sanxue ren yang li 2017Journal of Meteorological Research2017,31,5:25
2A random walk simulation of scalar mixing in flows through submerged vegetations显示文摘The scalar transport phenomena in vertical two-dimensional flows are studied using the random walk method. The established Lagrangian model is first applied to study the idealized longitudinal dispersion in open channels, before being used to investigate the scalar mixing characteristics of the flows through submerged vegetations. The longitudinal dispersion coefficients of the fully-developed boundary layer flows, with and without vegetations, are calculated based on the positions of the particles. A convenient way of incorporating the effects of vegetations is proposed, where all the flow parameters are regarded to be continually distributed over the depth. The simulation results show high accuracy of the developed random walk method, and indicate that the new method of accounting for the vegetation effects is appropriate for all the test cases considered. The predicted longitudinal dispersion coefficients agree well with the measurements. The merit of the new method is highlighted by its simplicity and efficiency in comparison with the conventional method that assumes the discontinuous distribution of the flow parameters over the depth.梁东方 WU Xuefei 2014Journal of Hydrodynamics2014,26,3:12
3Impact of HBV replication in peripheral blood mononuclear cell on HBV intrauterine transmission显示文摘Xiaohong Shi Xuefei Wang Xixi Xu Yongliang Feng Shuzhen Li Shuying Feng Bo Wang Suping Wang 2017Frontiers of Medicine2017,11,4:11
4Optimal allocation of hybrid energy storage for microgrids based on multi-attribute utility theory显示文摘To satisfy the requirements of high energy density,high power density,quick response and long lifespan for energy storage systems(ESSs),hybrid energy storage systems(HESSs)have been investigated for their complementary characteristics of‘high energy density components’and‘high power density components’.To optimize HESS combinations,related indices such as annual cost,fluctuation smoothing ability as well as safety and environmental impact have to be evaluated.The multiattribute utility method investigated in this paper is aimed to draw an overall conclusion for HESS allocation optimization in microgrid.Building on multi-attribute utility theory,this method has significant advantages in solving the incommensurability and contradiction among multiple attributes.Instead of determining the weights of various attributes subjectively,when adopting the multi-attribute utility method,the characteristics of attributes and the relation among them can be investigated objectively.Also,the proper utility function and merging rules are identified to achieve the aggregate utility which can reflect comprehensive qualities of HESSs.Xiaoshan FENG Jie GU Xuefei GUAN 2018Journal of Modern Power Systems and Clean Energy2018,6,1:11
5Opposing intraspecific vs.interspecific diversity effects on herbivory and growth in subtropical experimental tree assemblages显示文摘Aims Positive plant diversity-ecosystem function relations are ultimately driven by variation in functional traits among individuals that form a community.To date,research has largely focused on the role of species diversity for ecosystem functioning.However,substantial intraspecific trait variation is common and a significant part of this variation caused by genetic differences among individuals.Here,we studied the relative importance of species diversity and seed family(SF)diversity within species for growth and herbivory in experimental subtropical tree assemblages.Methods In 2010,we set up a field experiment in subtropical China,using four species from the local species pool.Trees were raised from seeds,with seeds from the same mother tree forming an SF.We established 23 plots containing one or four species(species diversity treatment)and one or four SFs per species(SF diversity treatment).Tree growth(stem diameter,plant height and crown expansion)and herbivory(percentage leaf loss due to leaf chewers)were monitored annually from 2011 to 2013.Important findings Tree species richness promoted growth but had no effect on herbivory.In contrast,SF diversity reduced growth and increased herbivory but only so in species mixtures.Most of the observed effects were time dependent,with the largest effect found in 2013.Our results suggest that biodiversity can affect plant performance directly via tree species-species interactions,or context dependent,via potential effects on inter-trophic interactions.Two important conclusions should be drawn from our findings.Firstly,in future studies regarding biodiversity and ecosystem functioning(BEF)relationships,intraspecific genetic diversity should be given similar weight as species diversity as it has often been neglected and its effects are not well understood.Secondly,we demonstrate opposite effects of biodiversity among and within species,stressing the importance to consider the effects of multiple levels of biodiversity simultaneously.Christoph Z.Hahn Pascal A.Niklaus Helge Bruelheide Stefan G.Michalski Miaomiao Shi Xuefei Yang Xueqin Zeng Markus Fischer Walter Durka 2017Journal of Plant Ecology2017,10,1:11
6Deacetylation of TFEB promotes fibrillar Aβ degradation by upregulating lysosomal biogenesis in microglia显示文摘Microglia 玩在由降级的 A 的清理的一个枢轴的角色他们在 lysosomes,在 Alzheimers 疾病(广告) 阻止淀粉的匾致病。最近的证据建议那个 lysosomal 机能障碍导致有毒的蛋白质总数的不够的消除。我们测试了是否与抄写因素 EB (TFEB ) 提高 lysosomal 功能,必要管理者 modulating lysosomal 小径,将在 microglia 支持一个清理。这里,我们证明 TFEB 的那 microglial 表情便于降级和还原剂扔了的纤丝状的 A (fA ) 淀粉的匾,它被 TFEB 的 deacetylation 进一步提高。用集体 spectrometry 分析,我们第一证实了是的 acetylation 一以前 TFEB 的 unreported 修正并且发现那 SIRT1 直接交往了与并且在离氨酸残余 116 点的 deacetylated TFEB。随后,当 TFEB 被击倒时, SIRT1 overexpression 由 TFEB 下游的目标的 upregulating transcriptional 层次提高了 lysosomal 功能和 fA 降级,它能被禁止。而且,在在 microglia 变异的 K116R 的 deacetylated TFEB 的 overexpression 由刺激 lysosomal 生物的续生说加速了细胞内部的 fA 降级并且极大地在 APP/PS1 转基因的老鼠的大脑片减少了扔的淀粉的匾。我们的调查结果表明 TFEB 的 deacetylation 能调整 lysosomal 生物的续生说和 fA 降级,为 attenuating 使 TFEB 的 microglial 激活成为可能的策略在广告的淀粉的匾免职。Jintao Bao Liangjun Zheng Qi Zhang Xinya Li Xuefei Zhang Zeyang Li Xue Bai Zhong Zhang Wei Huo Xuyang Zhao Shujiang Shang Qingsong Wang Chen Zhang Jianguo Ji 2016Protein & Cell2016,7,6:10
7Effects of methotrexate on the developments of heart and vessel in zebrafish显示文摘Methotrexate (MTX ) , folic 酸的一个对手,能禁止在 tetrahydrofolic 酸和胚胎的开发的合成很重要的 dihydrofolate reductase (DHFR ) 。在这研究,我们在暴露于 1.5 以后发现了那 ? 在 610 个小时的公里 MTX 授精以后, zebrafish 胚胎没能形成正常心血管的系统。在对待 MTX 的胚胎,室和中庭的词法发展被破坏,心脏的扭曲是反常的,心率和室的弄短部分被减少,并且脉管的发展被破坏。我们也与钙盐五水合物(CF ) 能在对待 MTX 的胚胎在心和容器引起改进开发的 folinic 酸与 dhfrgfp mRNA 或处理发现那任何一个 microinjection,它证明那 MTX 由禁止 DHFR 导致了畸形性。象 hand2, mef2a, mef2c,和 flk-1 那样的基因的抄本层次在对待 MTX 的胚胎被减少。与对待 MTX 的组相比, hand2, mef2a, mef2c,和 flk-1 的抄本层次在 MTX + dhfrgfp 被增加注射 mRNA 的组并且在 MTX + CF 组。我们的结果显示在对待 MTX 的胚胎的心和容器的破坏发展与 hand2, mef2a, mef2c,和 flk-1 的减少的抄本层次有关。Shuna Sun Yonghao Gui Yuexiang Wang Linxi Qian Xuefei Liu Qiu Jiang Houyan Song 2009Acta Biochimica et Biophysica Sinica2009,41,1:10
8Defined tumor antigen-specific T cells potentiate personalized TCR-T cell therapy and prediction of immunotherapy response显示文摘Personalized immunotherapy targeting tumor-specific antigens(TSAs)could generate efficient and safe antitumor immune response without damaging normal tissues.Although neoantigen vaccines have shown therapeutic effect in clinic trials,precise prediction of neoantigens from tumor mutations is still challenging.The host antitumor immune response selects and activates T cells recognizing tumor antigens.Hence,T cells engineered with T-cell receptors(TCRs)from these naturally occurring tumor antigen-specific T(Tas)cells in a patient will target personal TSAs in his/her tumor.To establish such a personalized TCR-T cell therapy,we comprehensively characterized T cells in tumor and its adjacent tissues by single-cell mRNA sequencing(scRNA-seq),TCR sequencing(TCR-seq)and in vitro neoantigen stimulation.Compared to bystander T cells circulating among tissues,Tas cells were characterized by tumor enrichment,tumor-specific clonal expansion and neoantigen specificity.We found that CXCL13 is a unique marker for both CD4^(+)and CD8^(+)Tas cells.Importantly,TCR-T cells expressing TCRs from Tas cells showed significant therapeutic effects on autologous patient-derived xenograft(PDX)tumors.Intratumoral Tas cell levels measured by CXCL13 expression precisely predicted the response to immune checkpoint blockade,indicating a critical role of Tas cells in the antitumor immunity.We further identified CD200 and ENTPD1 as surface markers for CD4^(^(+))and CD8^(^(+))Tas cells respectively,which enabled the isolation of Tas cells from tumor by Fluorescence Activating Cell Sorter(FACS)sorting.Overall,our results suggest that TCR-T cells engineered with Tas TCRs are a promising agent for personalized immunotherapy,and intratumoral Tas cell levels determine the response to immunotherapy.Jingjing He Xinxin Xiong Han Yang Dandan Li Xuefei Liu Shuo Li Shuangye Liao Siyu Chen Xizhi Wen Kuai Yu Lingyi Fu Xingjun Dong Kaiyu Zhu Xiaojun Xia Tiebang Kang Chaochao Bian Xiang Li Haiping Liu Peirong Ding Xiaoshi Zhang Zhenjiang Liu Wende Li Zhixiang Zuo Penghui Zhou 2022Cell Research2022,32,6:10
9First Imported Case of SARS-CoV-2 Omicron Subvariant BA.5—Shanghai Municipality,China,May 13,2022显示文摘On April 27,2022,an international flight KL857 from Amsterdam,the Netherlands arrived at Pudong International Airport,Shanghai Municipality.Passengers were transferred to the quarantine hotel for a routine 14-day medical observation in Songjiang District and regularly tested for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).One of the passengers(a 37-year-old Chinese male)was reported positive and diagnosed as a mild case on April 29.The case set out from Uganda(flight KL535)on April 25 and transferred at Amsterdam,the Netherlands on April 26 and Seoul,the Republic of Korea(KL857)on April 27.The patient has been vaccinated in four doses against coronavirus disease 2019(COVID-19)(Beijing Institute of Biological Products Co.,Ltd)in China and Uganda.After diagnosis,he was transferred to Shanghai Public Health Clinical Center for treatment.He recovered after treatment and was discharged on May 12.Hui Jiang Changcheng Wu Wenbo Xu Hongyou Chen Fanghao Fang Min Chen Chaonan Wang Lingyue Yuan Huanyu Wu Zheng Teng Jinyuan Guo Yaxu Zheng Xihong Lyu Xuefei Qiao Guizhen Wu Wenjie Tan Xi Zhang 2022China CDC weekly2022,4,30:10
10Exploiting Geo-Social Correlations to Improve Pairwise Ranking for Point-of-Interest Recommendation显示文摘Recently, as location-based social network(LBSN) rapidly grow, point-of-interest(POI) recommendation has become an important way to help people locate interesting places. Nowadays, there have been deep studies conducted on the geographical and social influence in the point-of-interest recommendation model based on the rating prediction. The fact is, however, relying solely on the rating fails to reflect the user's preferences very accurately, because the users are most concerned with the list of ranked point-of-interests(POIs) on the actual output of recommender systems. In this paper, we propose a co-pairwise ranking model called Geo-Social Bayesian Personalized Ranking model(GSBPR), which is based on the pairwise ranking with the exploiting geo-social correlations by incorporating the method of ranking learning into the process of POI recommendation. In this model, we develop a novel BPR pairwise ranking assumption by injecting users' geo-social preference. Based on this assumption, the POI recommendation model is reformulated by a three-level joint pairwise ranking model. And the experimental results based on real datasets show that the proposed method in this paper enjoys better recommendation performance compared to other state-of-the-art POI recommendation models.Rong Gao Jing Li Bo Du Xuefei Li Jun Chang Chengfang Song Donghua Liu 2018China Communications2018,15,7:9
11Expanded endoscopic therapy criteria should be cautiously used in intramucosal gastric cancer显示文摘Objective: Accurate estimation of lymph node metastasis(LNM) in intramucosal gastric cancer is essential to select less invasive treatment options and even avoid surgery. The aim of this study was to evaluate combined clinicopathological features to predict the presence of LNM.Methods: A retrospective review of data from 386 intramucosal gastric cancer patients who underwent gastrectomy with extended lymphadenectomy from 2003 to 2010 was conducted. The mutual relation between clinicopathological characteristics and LNM was analyzed.Results: LNM was detected in 40(10.4%) of the 386 patients. Histological type and vascular or lymphatic invasion presence showed a positive correlation with LNM occurrence by univariate analysis. Multivariate analysis revealed that histological type was the only factor associated with LNM. Combined clinicopathologic characteristics would be more predictable for LNM. We found no LNM when we used combined clinicopathological characteristics conforming to Japanese absolute indications for endoscopic therapy. The LNM rate was as high as 8.7% when Japanese expanded criteria were used. Univariate analysis in cancer conformity to expand endoscopic submucosal dissection(ESD) indication also revealed that the undifferential type was the only significant factor for LNM.Conclusions: It was possible to predict intramucosal gastric cancer cases without LNM using combined clinicopathological characteristic analysis. Extended indication for ESD should be cautiously used for intramucosal gastric cancer patients.Hongshan Wang Heng Zhang Cong Wang Yong Fang Xuefei Wang Weidong Chen Fenglin Liu Kuntang Shen Xinyu Qin Zhenbin Shen Yihong Sun 2016Chinese Journal of Cancer Research2016,28,3:8
12Ages, Trace Elements and Hf-Isotopic Compositions of Zircons from Claystones around the Permian-Triassic Boundary in the Zunyi Section, South China: Implications for Nature and Tectonic Setting of the Volcanism显示文摘证据的成长身体证明二叠三叠纪的边界(PTB ) 附近的那个火山作用可能在触发 PermianTriassic (PTr ) 是关键的集体扑灭。因此,在华南的 PTB 附近的灰床可以在这个事件上带信息。三暴烈的灰层,改变了到泥土,在在 Zunyi 节的 PTB 床上的 outcropped,贵州省,西南中国。从这三张灰床的锆石谷物的 U-Pb 年龄,踪迹元素,和 Hf 同位素作文用 LA-ICPMS 和 LA-MC-ICPMS 被分析。锆石主要除了二 inherited/xenocrystic 锆石(939 和 2 325 妈) 是在起源(241-279 妈) 的 magmatic。这些 magmatic 锆石的年龄显示发生在中间附近的 magmatism 的三个事件 -- 晚二叠的边界(~ 261.5 妈, MLPB ) , Wuchiapingian-Changhsingian 边界(~ 254.5 妈, WCB ) ,并且 PTB (~ 250.5 妈) 分别地。MLPB 和 WCB 附近的 magmatism 的开始的二个事件可以被归因于 magmatic 继承或重新免职。所有 magmatic 锆石分享类似的踪迹元素和 Hf 同位素作文。他们有 Y, Hf, Th 和 U 内容和 Nb/Ta 比率典型地代表从硅的计算碱的岩浆的锆石。这些锆石也与 -11.4 的 Hf (t) 价值展出充实的 Hf 同位素作文到 +0.2,它建议三个 magmatic 事件涉及大陆人外壳融化。更多的充实的 Hf 同位素作文(床 ZY13 的 Hf (t)=-11.4--4.8)(~ 250.5 妈) 在岩浆暗示古老的外壳的材料的更多的输入。magmatic 锆石的 Hf 同位素和踪迹元素作文的集成建议 magmatism 的这三个事件可以由于 Palaeo-Tethys 海洋的闭合沿着会聚的大陆边缘发生在或在西南的华南附近。Qiuling Gao Zhong-Qiang Chen Ning Zhang William L.Griffin Wenchen Xia Guoqing Wang Tengfei Jiang Xuefei Xia Suzanne Y.O'Reilly 2015Journal of Earth Science2015,26,6:8
13Arsenic trioxide promotes senescence and regulates the balance of adipogenic and osteogenic differentiation in human mesenchymal stem cells显示文摘砷三氧化物(ATO ) 能在肿瘤房间作为反肿瘤药导致区别和 apoptosis。间充质的干细胞(MSC ) 在骨头髓的造血作用起重要作用。许多报告证明了 MSC adipogenic 和 osteogenic 区别的混乱发生在一些疾病。然而,关于 MSC 上的 ATO 的效果的报告是有限的。在这研究,我们发现 1 M ATO 主要通过 p21 支持了 MSC 老朽,尽管它没在这剂量在 apoptosis 上有效果。而且, ATO 支持了 adipogenic 区别,但是在 MSC 禁止了 osteogenic 区别。我们的学习也显示出那 CCAAT/enhancer-binding 蛋白质 alpha C/EBP 和 peroxisome 激活 proliferator 的受体 gamma PPAR 可能涉及 ATO 导致的 adipogenic 和 osteogenic 区别的规定。我们的结果显示 ATO 可以由影响骨头髓微型环境施加反肿瘤效果。而且,它可以调整 MSC 的 adipogenic 和 osteogenic 区别。Huanchen Cheng Lin Qiu Hao Zhang Mei Cheng Wei Li Xuefei Zhao Keyu Liu Lei Lei Jun Ma 2011Acta Biochimica et Biophysica Sinica2011,43,3:8
14A Comparative Analysis of Evaporate Sediments on Earth and Mars: Implications for the Climate Change on Mars显示文摘The knowledge of Martian salts has gone through substantial changes during the past decades. In the 70th of last century, Viking landers have noticed the existence of salts on Mars. Several salt species have been suggested from then on, such as sulfates and chlorides. However, their origin was a mystery due to the lack of observations. The recent explorations and related studies at the beginning of this century revealed that the crustal composition of Mars is similar to that of Earth, and it was hypothesized that almost one third of Martian surface was covered by oceans and lakes in the early stage of Mars. The huge water bodies may have dissolved a large quantity of ions from Martian primary rocks during the whole Noachian and Hesperian epoch. After the enormous drought event happened during the late Hesperian and the early Amazonian, these dissolved ions have formed huge salts deposits and most of them were preserved on Mars until today. To date, carbonates, sulfates, chlorides have all been detected by orbital remote sensing and by landers and rovers. However, the salt mineral assemblages on Mars seems to have some differences from those on Earth, e.g., rich in sulfates and lack of massive carbonates. To explain this difference, we propose that most of the surface carbonates precipitated from the ancient oceans may have been dissolved by the later ubiquitous acidic fluids originated from the global volcanism in the Hesperian era, and formed the enormous sulfate deposits as detected, and this hypothesis seems to be supported by the evidence that most of the sulfate deposits distribute around the Tharsis volcanic province while the survived carbonates located far from it. This process can release most of the carbon on Mars to the atmosphere in the form of CO2 and then be erased by the late heavy bombardments, which might have profound influence on the climate change happened in the Hesperian age. The positive correlation between the GRS results of the potassium distributions and the distribution of chlorides on Mars, together with the high Br concentration measured from the evaporate sediments at two Mars exploration rover landing sites, indicate that the brines in the regions where the chlorides deposited may have reached the stage for potassium salts deposition, thus we propose for the first time that potassium salts deposits might be prevalent in these regions.ZHENG Mianping KONG Weigang ZHANG Xuefei CHEN Wenxi KONG Fanjing 2013Acta Geologica Sinica(English Edition)2013,87,3:7
15Modeling and prediction for the acute toxicity of pesticide mixtures to the freshwater luminescent bacterium Vibrio qinghaiensis sp.-Q67显示文摘In China, water pollution by pesticide mixtures has constituted a serious environmental problem due to potential toxicity and bioaccumulation. But few pesticide combinations have exactly similar and dissimilar mechanisms of action. For this purpose, in tests with the freshwater luminescent bacterium (Vibrio qinghaiensis sp.-Q67), ten pesticides, including three herbicides and seven insecticides, were selected as test substances. Concentration response analysis was performed for ten individual substances, and for mixtures containing all ten substances in twelve different concentration ratios (based on UDCR and EECR methods). The observed mixture toxicity was compared with predictions by the two models, concentration addition (CA) and independent action (IA). The toxicity of the tested mixtures showed a good agreement with those predicted by the concept of CA except four UDCR mixtures: UD10-2, UD10-4, UD10-8 and UD10-10. To examine the influence of imidacloprid in the four UDCR mixtures (UD10-2, UD10-4, UD10-8, UD10-10), it was removed from the ten-pesticide mixtures and the remaining nine chemicals were combined at the same relative proportions based on the UDCR method (UD9-2, UD9-4, UD9-8, UD9-10). There was not significant departure from CA for the scattered points with the nine remaining pesticides omitting imidacloprid. Thus, imidacloprid may significantly influence the other pesticides due to its properties.Xuefei Zhou, Wenjing Sang, Shushen Liu, Yalei Zhang, Huilin GeState Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. 2010Journal of Environmental Sciences2010,22,3:7
16Theory and experimental verification of valveless piezoelectric pump with rotatable unsymmetrical slopes显示文摘A valveless piezoelectric pump with rotatable unsymmetrical slopes is developed in this research.It has the following features:The pump integrates driving and transporting,and it can mix different fluids while transporting them.In this paper,firstly,the design of the valveless piezoelectric pump with rotatable unsymmetrical slopes was proposed,and the single-direction flow principle was explained.Then,the fluid mechanics model of the valveless piezoelectric pump with rotatable unsymmetrical slopes was established.Meanwhile,the numerical simulation of the pump was performed.Finally,the experiments on relationship between the rotation angles of the slope and the flow rates were conducted.The experimental results showed that the maximum flow was 32.32 mL min 1.The maximum relative error between the theoretical results and the experimental ones was 14.59%.For the relationship between rotation angles and flow ratio of two inlets,the relative error between the experimental and theoretical maxima was 3.75%.Thus,the experiments proved the feasibility of the pump design and verified the theory.ZHANG JianHui XIA QiXiao HUANG Yi LENG XueFei HUANG Jun ZHAO ChunSheng 2011Science China(Technological Sciences)2011,54,11:7
17Aerosol Hygroscopicity during the Haze Red-Alert Period in December 2016 at a Rural Site of the North China Plain显示文摘A humidification system was deployed to measure aerosol hygroscopicity at a rural site of the North China Plain during the haze red-alert period 17–22 December 2016. The aerosol scattering coefficients under dry [relative humidity(RH) < 30%] and wet(RH in the range of 40%–85%) conditions were simultaneously measured at wavelengths of450, 550, and 700 nm. It is found that the aerosol scattering coefficient and backscattering coefficient increased by only 29% and 10%, respectively when RH went up from 40% to 80%, while the hemispheric backscatter fraction went down by 14%, implying that the aerosol hygroscopicity represented by the aerosol scattering enhancement factor f(RH) is relatively low and RH exerted little effects on the aerosol light scattering in this case. The scattering enhancement factors do not show significant differences at the three wavelengths, only with an approximate 2% variation, suggesting that the aerosol hygroscopicity is independent of the wavelength. Aerosol hygroscopicity is highly dependent on the aerosol chemical composition. When there is a large mass fraction of inorganics and a small mass fraction of organic matter, f(RH) reaches a high value. The fraction of NO_3^- was strongly correlated with the aerosol scattering coefficient at RH = 80%, which suggests that NO_3^- played an important role in aerosol hygroscopic growth during the heavy pollution period.Xuefei QI Junying SUN Lu ZHANG Xiaojing SHEN Xiaoye ZHANG Yangmei ZHANG Yaqiang WANG Haochi CHE Zhouxiang ZHANG Junting ZHONG Kaiyan TAN Huarong ZHAO Sanxue REN 2018Journal of Meteorological Research2018,32,1:7
18The Formation of the Jiaodong Gold Province显示文摘Gold deposits in Jiaodong,termed Jiaodong-type,are tectonically located in the southeastern margin of the North China Craton.Their major features are reviewed in this paper to highlight the differences between Jiaodong deposits and other genetic types of gold deposits.The mineralization was synchronized with asthenosphere upwelling indicated by synore OIB-like mafic dike and large-scale crustal thinning suggested by decrease of Sr/Y from pre-ore to syn-ore granites.Asthenosphere upwelling induced by the roll-back of Paleo-Pacific Plate drove partial melting of lithospheric mantle and devolatilization,which induced the release of the ore-forming fluids.In concomitant with magmatic records,mineralization migrated from the western Jiaobei terrane(133–127 Ma)to the eastern Sulu orogenic belt(114–108 Ma),corresponding to the eastward roll-back of Paleo-Pacific Plate.Gold mineralization in Jiaodong formed in the transitions of ductile to brittle deformation,rapid to slow crustal uplift,and regional compression to extension.In the regional-scale,the gold deposits in the Jiaobei terrane are mostly situated at intersections between NE-trending faults and EW-trending basement faults,and gold orebodies dominantly controlled by the lithologic contacts between Precambrian metamorphic rocks and Mesozoic granites.The mineralization was dominated by the disseminated-veinlet ores related to quartz–sericite alteration in strong cataclasite-breccia zone,with subsidiary thick quartz-sulfide veins developed in secondary fault zones.The ore-forming fluids belong to a H_(2)O–CO_(2)–NaCl±CH_(4)system and show minor variations in salinity among different types of ore.Structure-fluid feedback involving fluid-rock reaction and hydrofracturing triggered the fluid phase separation and resultant gold deposition.The Jiaodong gold deposits are distinct from orogenic and intrusion-related gold deposits in terms of tectonic setting,origin of ore-forming fluids,and mechanism of gold deposition.DENG Jun WANG Qingfei LIU Xuefei ZHANG Liang YANG Liqiang YANG Lin QIU Kunfeng GUO Linnan LIANG Yayun MA Yao 2022Acta Geologica Sinica(English Edition)2022,96,6:7
19Impact of tree diversity and environmental conditions on the survival of shrub species in a forest biodiversity experiment in subtropical China显示文摘Aims Although shrubs are an important component of forests,their role has not yet been considered in forest biodiversity experiments.In the biodiversity-ecosystem functioning(BEF)experiment with subtropical tree species in south-east China(BEF-China),we factorially combined tree with shrub species-diversity treatments.Here,we tested the hypotheses that shrub survival differs between the 10 planted shrub species,with lower survival rates of late-than early-successional species and is affected by environmental conditions,such as topography and top soil characteristics,as well as by biotic factors,represented by tree,shrub and herb layer characteristics.Methods We analyzed the survival of 42000 shrub individuals in 105 plots varying in tree and shrub species richness of the BEF-China project four years after planting.Shrub survival was analyzed with generalized linear mixed effects models at the level of individuals and with variance partitioning at the plot level.Random intercept and random slope models of different explanatory variables were compared with respect to the Bayesian Information Criterion(BIC).Important Findings Survival rates differed largely between the 10 shrub species,ranging from 26%to 91%for Ardisia crenata and Distylium buxifolium,respectively.Irrespective of species identity,single abiotic factors explained up to 5%of species survival,with a negative effect of altitude and slope inclination and a positive effect of the topsoil carbon to nitrogen ratio,which pointed to drought as the major cause of shrub mortality.In contrast,neither tree nor shrub richness affected shrub survival at this early stage of the experiment.Among the biotic predictors,only herb layer species richness and cover of the dominant fern species(Dicranopteris pedata)affected shrub survival.Overall,our models that included all variables could explain about 65%in shrub survival,with environmental variables being most influential,followed by shrub species identity,while tree species diversity(species richness and identity)and herb layer characteristics contributed much less.Thus,in this early stage of the experiment the biotic interactions among shrubs and between shrubs and trees have not yet overruled the impact of abiotic environmental factors.Bo Yang Ying Li Bingyang Ding Sabine Both Alexandra Erfmeier Werner Härdtle Keping Ma Bernhard Schmid Thomas Scholten Gunnar Seidler Goddert von Oheimb Xuefei Yang Helge Bruelheide 2017Journal of Plant Ecology2017,10,1:7
20The precise regulation of different COR genes by individual CBF transcription factors in Arabidopsis thaliana显示文摘The transcription factors CBF1/2/3 are reported to play a dominant role in the cold responsive network of Arabidopsis by directly regulating the expression levels of cold responsive(COR) genes.In this study,we obtained CRISPR/Cas9-mediated loss-of-function mutants of cbf1$3.Over 3,000 COR genes identified by RNA-seq analysis showed a slight but significant change in their expression levels in the mutants compared to the wildtype plants after being treated at 4 °C for 12 h.The C-repeat(CRT) motif(50-CCGAC-30) was enriched in promoters of genes that were up-regulated by CBF2 and CBF3 but not in promoters of genes up-regulated by CBF1.These data suggest that CBF2 and CBF3 play a more important role in directing the cold response by regulating different sets of downstream COR genes.More than 2/3 of COR genes were co-regulated by two or three CBFs and were involved mainly in cellular signal transduction and metabolic processes;less than 1/3 of the genes were regulated by one CBF,and those genes up-regulated were enriched in cold-related abiotic stress responses.Our results indicate that CBFs play an important role in the trade-off between cold tolerance and plant growth through the precise regulation of COR genes in the complicated transcriptional network.Yihao Shi Jiaying Huang Tianshu Sun Xuefei Wang Chenqi Zhu Yuxi Ai Hongya Gu 2017Journal of Integrative Plant Biology2017,59,2:7
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