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    题名 作者 年代 出处 被引量
1Transplantation of UC-MSCs on collagen scaffold activates follicles in dormant ovaries of POF patients with long history of infertility显示文摘Premature ovarian failure(POF) is a refractory disease for clinical treatment with the goal of restoring fertility. In this study,umbilical cord mesenchymal stem cells on a collagen scaffold(collagen/UC-MSCs) can activate primordial follicles in vitro via phosphorylation of FOXO3 a and FOXO1. Transplantation of collagen/UC-MSCs to the ovaries of POF patients rescued overall ovarian function, evidenced by elevated estradiol concentrations, improved follicular development, and increased number of antral follicles. Successful clinical pregnancy was achieved in women with POF after transplantation of collagen/UC-MSCs or UC-MSCs. In summary, collagen/UC-MSC transplantation may provide an effective treatment for POF.Lijun Ding Guijun Yan Bin Wang Lu Xu Yan Gu Tong Ru Xiaoying Cui Lei Lei Jingyu Liu Xiaoqiang Sheng Bin Wang Chunxue Zhang Yanjun Yang Ruiwei Jiang Jianjun Zhou Na Kong Feifei Lu Huaijun Zhou Yannan Zhao Bing Chen Yali Hu Jianwu Dai Haixiang Sun 2018Science China(Life Sciences)2018,61,12:43
2A Review of Novel Leakage Current Suppression Techniques for Transformerless Photovoltaic Inverters显示文摘漏电流抑制是无变压器型光伏并网系统需要解决的关键问题之一。VDE-0126-1-1标准规定,漏电流高于300 mA时光伏并网系统必须在0.3 s内从电网中切除。为了解释漏电流的根源,建立系统共模电压数学模型,在此基础上分析漏电流产生的原因,探讨不同调制策略对漏电流的影响,然后介绍几种典型的、能够有效抑制漏电流的电路拓扑结构,并分析各种拓扑的工作原理和特点。最后对漏电流抑制技术方面的发展趋势做了展望。WU Weiyang GUO Xiaoqiang 2012中国电机工程学报2012,32,18:32
3Degradation of chlorpyrifos in laboratory soil and its impact on soil microbial functional diversity显示文摘Degradation of chlorpyrifos at different concentrations in soil and its impact on soil microbial functional diversity were investigated under laboratory condition.The degradation half-live of chlorpyrifos at levels of 4,8,and 12 mg/kg in soil were calculated to be 14.3,16.7,and 18.0 d,respectively.The Biolog study showed that the average well color development(AWCD) in soils was significantly(P < 0.05) inhibited by chlorpyrifos within the first two weeks and thereafter recovered to a similar level as the control.A similar variation in the diversity indices(Simpson index 1/D and McIntosh index U) was observed,but no significant difference among the values of the Shannon-Wiener index H was found in chlorpyrifos-treated soils.With an increasing chlorpyrifos concentration,the half-life of chlorpyrifos was significantly(P 0.05) extended and its inhibitory effect on soil microorganisms was aggravated.It is concluded that chlorpyrifos residues in soil had a temporary or short-term inhibitory effect on soil microbial functional diversity.FANG Hua YU Yunlong CHU Xiaoqiang WANG Xiuguo YANG Xiaoe YU Jingquan 2009Journal of Environmental Sciences2009,21,3:25
4Regional patterns of particulate spectral absorption in the Pearl River estuary显示文摘Spectral absorption coefficients of the total particulate, ap(l ), nonalgal particulate, ad(l ), and phyto-plankton pigment, aph(l ), in the Pearl River estuary and its vicinity waters were determined using the quantitative filter technique. The particulate absorption ap(443) ranged from 0.04 to 1.82 m-1, with the corresponding aph(443) ranging from 0.016 to 0.484 m-1. Two typical spectral patterns are found for the total particulate absorption. For the first typi-cal spectral pattern, the total particulate absorption spectra are similar to that of nonalgal particulate, with values of absorption coefficient decreasing with wavelength. In con-trast, for the second spectral pattern the spectral absorptions by total particulate are very similar to that of phytoplankton pigment. The spectral dependency of absorption by nonalgal particulate follows an exponential increase toward short wavelengths, with an average slope of 0.012±0.002 nm-1. The nonalgal absorption and the fraction of the nonalgal particulate absorption to the total particulate absorption exhibit a distinct trend of decreasing with salinity of the sur-face water. Phytoplankton pigment absorption exhibits a clear trend of increasing nonlinearly with chlorophyll a con-centration. The relationships between the phytoplankton pigment absorption and chlorophyll a concentration can be described by power law, with the determination coefficient r2 of 0.82. But only weak relationships between ap(l ) and chlorophyll a concentration are observed, with the determination coefficient r2 of 0.42. The relatively large scatter around ap(443) versus chl-a relationship would be attributed to the effects of loading of the nonalgal particulate absorption. Our analysis indicated that such relationships similar to that for Case Ⅰ waters can be applicable to optically complex Case Ⅱ waters if the effects caused by nonalgal are corrected. The chlorophyll-specific absorption coefficients of phytoplankton pigment are not constant, it increases with decreasing chlorophyll a level. To improve the accuracy of bio-optical algorithms for remote sensing in coastal waters, further investigations on the variations of specific absorption of chlorophyll pigment must be made.CAO Wenxi, YANG Yuezhong, XU Xiaoqiang, HUANG Liangmin & ZHANG Jianlin LED Laboratory, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China Correspondence should be addressed to Cao Wenxi (e-mail: wxcao@ scsio.ac.cn) 2003Chinese Science Bulletin2003,48,21:24
5Understanding of myofascial trigger points显示文摘Zhuang Xiaoqiang Tan Shusheng Huang Qiangmin 2014Chinese Medical Journal2014,,24:22
6Metal Flowing of Involute Spline Cold Roll-beating Forming显示文摘The present research on involute spline cold roll-beating forming is mainly about the principles and motion relations of cold roll-beating,the theory of roller design,and the stress and strain field analysis of cold roll-beating,etc.However,the research on law of metal flow in the forming process of involute spline cold roll-beating is rare.According to the principle of involute spline cold roll-beating,the contact model between the rollers and the spline shaft blank in the process of cold roll-beating forming is established,and the theoretical analysis of metal flow in the cold roll-beating deforming region is proceeded.A finite element model of the spline cold roll-beating process is established,the formation mechanism of the involute spline tooth profile in cold roll-beating forming process is studied,and the node flow tracks of the deformation area are analyzed.The experimental research on the metal flow of cold roll-beating spline is conducted,and the metallographic structure variation,grain characteristics and metal flow line of the different tooth profile area are analyzed.The experimental results show that the particle flow directions of the deformable bodies in cold roll-beating deformation area are determined by the minimum moving resistance.There are five types of metal flow rules of the deforming region in the process of cold roll-beating forming.The characteristics of involute spline cold roll-beating forming are given,and the forming mechanism of involute spline cold roll-beating is revealed.This paper researches the law of metal flow in the forming process of involute spline cold roll-beating,which provides theoretical supports for solving the tooth profile forming quality problem.CUI Fengkui WANG Xiaoqiang ZHANG Fengshou XU Hongyu QUAN Jianhui LI Yan 2013Chinese Journal of Mechanical Engineering2013,26,5:19
7Darwin:a neuromorphic hardware co-processor based on Spiking Neural Networks显示文摘Broadly speaking, the goal of neuromorphic engineering is to build computer systems that mimic the brain. Spiking Neural Network(SNN) is a type of biologically-inspired neural networks that perform information processing based on discrete-time spikes, different from traditional Artificial Neural Network(ANN).Hardware implementation of SNNs is necessary for achieving high-performance and low-power. We present the Darwin Neural Processing Unit(NPU), a neuromorphic hardware co-processor based on SNN implemented with digitallogic, supporting a maximum of 2048 neurons, 20482= 4194304 synapses, and 15 possible synaptic delays.The Darwin NPU was fabricated by standard 180 nm CMOS technology with an area size of 5 × 5 mm2and70 MHz clock frequency at the worst case. It consumes 0.84 m W/MHz with 1.8 V power supply for typical applications. Two prototype applications are used to demonstrate the performance and efficiency of the hardware implementation.Juncheng SHEN De MA Zonghua GU Ming ZHANG Xiaolei ZHU Xiaoqiang XU Qi XU Yangjing SHEN Gang PAN 2016Science China(Information Sciences)2016,59,2:18
8Agriculture Green Development: a model for China and the world显示文摘Realizing sustainable development has become a global priority.This holds,in particular,for agriculture.Recently,the United Nations launched the Sustainable Development Goals(SDGs),and the Nineteenth National People’s Congress has delivered a national strategy for sustainable development in China—realizing green development.The overall objective of Agriculture Green Development(AGD)is to coordinate'green'with'development'to realize the transformation of current agriculture with high resource consumption and high environmental costs into a green agriculture and countryside with high productivity,high resource use efficiency and low environmental impact.This is a formidable task,requiring joint efforts of government,farmers,industry,educators and researchers.The innovative concept for AGD will focus on reconstructing the whole crop-animal production and food production-consumption system,with the emphasis on high thresholds for environmental standards and food quality as well as enhanced human well-being.This paper addresses the significance,challenges,framework,pathways and potential solutions for realizing AGD in China,and highlights the potential changes that will lead to a more sustainable agriculture in the future.Proposals include interdisciplinary innovations,whole food chain improvement and regional solutions.The implementation of AGD in China will provide important implications for the countries in developmental transition,and contribute to global sustainable development.Jianbo SHEN Qichao ZHU Xiaoqiang JIAO Hao YING Hongliang WANG Xin WEN Wen XU Tingyu LI Wenfeng CONG Xuejun LIU Yong HOU Zhenling CUI Oene OENEMA William JDAVIES Fusuo ZHANG 2020Frontiers of Agricultural Science and Engineering2020,7,1:18
9ESCRT-I Component VPS23A Affects ABA Signaling by Recognizing ABA Receptors for Endosomal Degradation显示文摘受体在过去的十年在植物科学成为了很重要的进展之一的 PYR/PYL/RCAR-type abscisic 酸(骆驼毛的织物) 的最近的发现。在哺乳动物,排序的 endosomal 充当一条重要小径到 downregulate 受体的不同类型,而是它在植物荷尔蒙发信号的角色糟糕被理解。这里,我们报导那 ubiquitin 象 E2 一样蛋白质, VPS23A,是 ESCRT-I 的一个关键部件,否定地调整骆驼毛的织物发信号。VPS23A 与 PYR/PYL/RCAR-type 骆驼毛的织物受体和提高的 VPS23A 的混乱有 epistatic 关系在在骆驼毛的织物处理下面表明小径的 ABA 的关键 kinase OST1 的活动。而且, VPS23A 与 PYR1/PYLs 交往,连接 K63 的 diubiquitin,和 PYL4 在 vivo 拥有连接 K63 的 ubiquitinated 修正。进一步的分析表明 VPS23A 影响 PYR1 和 PYL4 的稳定性的 subcellular 本地化。一起拿,我们的结果建议 VPS23A 经由调停液泡的降级影响 PYR1/PYL4,提供两个的先进理解在植物荷尔蒙发信号的骆驼毛的织物受体和 ESCRT 的周转。Feifei Yu Lijuan Lou Miaomiao Tian Qingliang Li Yanglin Ding Xiaoqiang Cao Yaorong Wu Borja Belda-Palazon Pedro L. Rodriguez Shuhua Yang Qi Xie 2016Molecular Plant2016,9,12:17
10Blending Scheduling under Uncertainty Based on Particle Swarm Optimization Algorithm显示文摘Blending is an important unit operation in process industry. Blending scheduling is nonlinear optimiza- tion problem with constraints. It is difficult to obtain optimum solution by other general optimization methods. Particle swarm optimization (PSO) algorithm is developed for nonlinear optimization problems with both contin- uous and discrete variables. In order to obtain a global optimum solution quickly, PSO algorithm is applied to solve the problem of blending scheduling under uncertainty. The calculation results based on an example of gasoline blending agree satisfactory with the ideal values, which illustrates that the PSO algorithm is valid and effective in solving the blending scheduling problem.ZHAO Xiaoqiang(赵小强) RONG Gang(荣冈) 2005Chinese Journal of Chemical Engineering2005,13,4:16
11Degradation of chlorpyrifos alone and in combination with chlorothalonil and their effects on soil microbial populations显示文摘在实践,杀虫剂通常为庄稼保护同时或一个接一个被使用,并且这类杀虫剂申请经常在土壤环境导致杀虫剂残余的联合污染。实验室研究被进行在土壤上在 chlorpyrifos 降级和它的效果上调查 chlorothalonil 的影响细菌,真菌,并且放射菌类人口。在这里的试验性的条件下面, chlorpyrifos 的一半生活独自,并且在有 chlorothalonil 的联合,在推荐并且两倍剂量,被测量分别地是 3.24, 2.77,和 2.63 d。Chlorpyrifos 降级没被它的联合显著地与 chlorothalonil 改变。然而,土壤微生物上的 chlorpyrifos 的禁止的效果被它的联合与 chlorothalonil 增加,并且增加与增加的 chlorothalonil 的层次有关。在控制,细菌的人口,真菌,和放射菌类比作那些分别地,被 chlorpyrifos 被 44.1% , 61.1% ,和 72.8% 显著地独自在处理(DAT ) 以后在第一天减少。与 chlorothalonil 的增加,抑制在推荐剂量被增加到 55.2% , 79.3% ,和 85.8% ,并且 86.0% , 94.1% ,和 90.8% 在双剂量在一 DAT,分别地。结果建议联合效果应该被考虑估计杀虫剂应用的实际影响。CHU Xiaoqiang FANG Hua PAN Xuedong WANG Xiao SHAN Min FENG Bo YU Yunlong 2008Journal of Environmental Sciences2008,20,4:16
12The cross talk between long, non-coding RNAs and microRNAs in gastric cancer显示文摘胃的癌症是最普通的恶意的疾病之一并且仍然是世界范围的癌症相关的死亡的第二个领先的原因。尽管大努力在过去的十年期间被作了便于胃的癌症的早察觉和治疗,预后是还没令人满意的,胃的癌症致病的内在的分子的机制充分没被理解。同时,非编码的 RNA 在调整各种各样的生物、病理学的过程作为关键播放器被建立了,例如房间周期前进,改变的染色质,基因抄写,并且 posttranscriptional 处理。而且,众多的研究也在非编码的 RNA 的不同种类之中揭示了复杂相互影响;因此,在长非编码的 RNA (lncRNAs ) 和 microRNAs (miRNAs ) 之间跨规定开始出现了。这次 lncRNAmiRNA 十字谈话,在最近的年里吸引了增加的注意,包括胃的癌症涉及很多人的疾病。在这评论,我们总结在 lncRNAs 和 miRNAs 之间的相互作用的最近的研究进步,加亮他们对提供为癌症诊断和治疗的新奇途径的胃的癌症的发展和前进的影响。Kaiyuan Deng Hao Wang Xiaoqiang Guo Jiazeng Xia 2016Acta Biochimica et Biophysica Sinica2016,48,2:16
13New progress in the Holocene climate and agriculture research in China显示文摘Global climate change and its possible ecological consequences have become the focused issue(IPCC,2007;Mann et al.,2008;Ding et al.,2009).The Holocene contains the analogous characteristic of future climatic change and the continuous agriculture activity,providing the ideal'similar pattern'for studying the climate change and human adaption and impact in the future.Based on the recent studies of stalagmite,ice core,ocean,and lake etc.,the paper introduces the new progress in the Holocene climate and agriculture research in China as follows:(1)Discuss the variability,amplitude,and unstable characteristic of climate,as well as the abrupt events and mechanisms of climate.(2)Analyze the botanical index records for studying the early agriculture.(3)Review the agricultural origin,expanding,and development.(4)Reveal the style and intensity of early agriculture and understand the agricultural impact and adaption to the environmental changes.(5)Introduce ongoing research projects in China and emphasize the significance of increasing the dating precision and the indicative effectiveness of proxies.(6)Realize how the ecosystem and environmental factors respond to the increasing temperature process,understand how the human adapt to the rapid climate change,and provide the scientific basis for assessing the effects of climate change and the human adaption in the future.LI XiaoQiang 2013Science China Earth Sciences2013,56,12:15
14Modern pollen rain in the Lake Qinghai basin, China显示文摘Lake Qinghai is the largest inland brackish lake in China and lies within the NE Tibetan Plateau. Our study shows that pollen assemblages in each vegetation belt are significantly correlated with the vegetation types of this area. Among the herbaceous and shrubby pollen assemblages, Artemisia is over-represented, while Poaceae, Cyperaceae and Polygonaceae are under-represented. Artemisia/ Chenopodiaceae (A/C) ratios with the regional vegetation characteristic can be used as a proper index to reconstruct the history of vegetation and climate in Lake Qinghai basin. Modern pollen in the lake mainly comes from the nearby vegetation, controlled by the directions and velocity of the wind. The distribution of modern pollen in Lake Qinghai tends to be similar in most part of the lake. The difference of pollen sedimentation process in the lake can be potentially influenced by the focusing function of the lake, river streams, and lake current.SHANG Xue LI XiaoQiang AN ZhiSheng JI Ming ZHANG HongBin 2009Science China Earth Sciences2009,52,10:15
15A new bone repair scaffold combined with chitosan/ hydroxyapatite and sustained releasing icariin显示文摘Icariin, a plant-derived flavonol glycoside, has been proved as an osteoinductive agent for bone tissue engineering. A new bone repair scaffold was generated by thorough mixing of icariin and chitosan/ hydroxyapatite (icariin-CS/HA) using freeze-drying technigue. Characteristics of morphology, mechanical properties, biocompatibility, drug release behavior and bone repair abilities in vivo were evaluated. The results show that drug loading process of icariin did not affect physical structure of CS/HA composite significantly but decreased mechanical properies of CS/HA composite, which happened with a high dosage; icariin-CS/HA had favorable cell compatibility and promoted osteogenic differentiation of hBMSCs; the controlled release of icariin was satisfactory and the release retained after 90 d in vitro. In addition, icariin-CS/HA scaffolds had favorable osteoconduction and osteoinduction in vivo, and could fill bone defect sites and stimulate newborn bone tissues formation at early stage. On the basis of these data, icariin-CS/HA is believed to be an optical bone repair scaffold for tissue engineering.WU Tao NAN KaiHui CHEN JingDi JIN Dan JIANG Shan ZHAO PeiRan XU JunChang DU Hao ZHANG XiaoQiang LI JianWei PEI GuoXian 2009Chinese Science Bulletin2009,54,17:14
16Recent rapid shortening of crust across the Tianshan Mts. and relative motion of tectonic blocks in the north and south显示文摘Based on the multiple-epoch Global Positioning System observations during a period from 1992 to 1999, we document directly a rapid crustal shortening of -20 mm/a across the western Tianshan Mts. (76°E), in contrast to a 4 mm/a convergent rate across the eastern Tianshan Mts. (87°E) and the north-south convergence across the mountain belt descends laterally from west to east. The direction of current crustal movement inferred by GPS sites along the southern flank of the Tianshan Mts. is approximately perpendicular to the easterly-trending mountain belt, indicating that the Tarim Basin thrust almost rightly into the Tianshan Mts. The Tarim Basin accommodates nearly no or a minor, if any, crustal deformation and rotates clockwise, as a rigid body in a whole, at a rate of 0.64°/Ma around a Euler pole at 95.7° E, 40.3°N (Anxi, Gansu) with respect to the stable Siberia. The relative motion between the Kazakh platform and the Dzungarian Basin is quite apparent. The Dzungar should be regarded as anWANG Qi DING Guoyu QIAO Xuejun WANG Xiaoqiang YOU Xinzhao 2000Chinese Science Bulletin2000,45,21:14
17Modern pollen and vegetation relationships in the Yili Basin,Xinjiang, NW China显示文摘Fifty-six surface pollen samples from different vegetation zones in the Yili Basin,western Tianshan Mountains,Xinjiang were analyzed to examine the relationships between the surface pollen assemblages and the original vegetation.A pollen analysis and a vegetation investigation with a discriminant analysis show that the pollen assemblages greatly differ across disparate vegetation zones.Twelve pollen taxa can be used as significant types for vegetation reconstruction in the basin.These taxa were the most abundant in the surface pollen samples.Cupressaceae pollen percentages were greater than 1%in Cupressaceae shrubs.More than5%of Picea pollen indicates the growth of a Picea forest within 5 km.The subalpine meadow that is distributed widely in the basin is characterized by high content of Artemisia,Chenopodiaceae,Poaceae,Picea,Asteraceae,Taraxacum and Arenaria pollen types.The Artemisia-Chenopodiaceae-Poaceae-Cannabaceae pollen assemblages indicate the presence of montane steppe in the area.Artemisia and Chenopodiaceae pollen dominate the desert steppe and Populus forest.Artemisia pollen percentages were greater than 60%in the Artemisia desert,whereas Chenopodiaceae pollen percentages exceeded 65%in the Chenopodiaceae desert.The Artemisia/Chenopodiaceae(A/C)ratios reflect the vertical moisture changes in the Yili Basin.The mean A/C ratios were greater than 1.2 in the subalpine meadow and montane steppe that occupy the humid zone in the basin.These ratios were between1 and 1.2 in the Cupressaceae shrubs,desert steppe,Populus forest and floodplain meadow.The ratios were less than 0.5 in the Chenopodiaceae desert,which is an arid environment.ZHAO KeLiang LI XiaoQiang 2013Chinese Science Bulletin2013,58,33:14
18Complement C3 activation regulates the production of tRNA-derived fragments Gly-tRFs and promotes alcohol-induced liver injury and steatosis显示文摘Complement is known to play a role in alcoholic fatty liver disease (AFLD), but the underlying mechanisms are poorly understood, thereby constraining the development of a rational approach for therapeutic intervention in the complement system. C3 deficiency has been shown to impart protective effects against ethanol-induced hepatic steatosis and inflammation. Here we demonstrate a protection effect in wild-type mice by treatment with CR2-Crry, a specific inhibitor of C3 activation. The expression of glycine transfer (t) RNA-derived fragments (Gly-tRFs) is upregulated in ethanol-fed mice and inhibition of Gly-tRFs in vivo decreases chronic ethanol feeding-induced hepatosteatosis without affecting inflammation. The expression of Gly-tRF was downregulated in C3-deficient or CR2-Crry-treated mice, but not in C5-deficient mice;Gly-tRF expression was restored by the C3 activation products C3a or Asp (C3a-des-Arg) via the regulation of CYP2E1. Transcriptome profiling of hepatic tissues showed that Gly-tRF inhibitors upregulate the expression of sirtuin1 (Sirt1) and subsequently affect downstream lipogenesis and β-oxidation pathways. Mechanistically, Gly-tRF interacts with AGO3 to downregulate Sirt1 expression via sequence complementarity in the 3′ UTR. Notably, the expression levels of C3d, CYP2E1 and Gly-tRF are upregulated, whereas Sirt1 is decreased in AFLD patients compared to healthy controls. Collectively, our findings suggest that C3 activation products contribute to hepatosteatosis by regulating the expression of Gly-tRF. Complement inhibition at the C3 activation step and treatment with Gly-tRF inhibitors may be potential and precise therapeutic approaches for AFLD.Fudi Zhong Zhigao Hu Keqing Jiang Biao Lei Zhan Wu Guandou Yuan Hongliang Luo Chunqiang Dong Bo Tang Chaowen Zheng Shuai Yang Yonglian Zeng Zhenya Guo Shuiping Yu Huizhao Su Guo Zhang Xiaoqiang Qiu Stephen Tomlinson Songqing He 2019Cell Research2019,29,7:14
19Organelle pH in the Arabidopsis Endomembrane System显示文摘细胞内部的分隔空间的 pH 为房间的生存能力是必要的。尽管有它的关联,很少对这些分隔空间的 pH 被知道。到在 vivo 的措施 pH,我们首先由联合修改溶解度的绿色的改进溶解度的特征产生了二个 pH 传感器荧光灯有 pHluorins 和 codon 的察觉到 pH 能力的蛋白质(GFP )(smGFP ) 在 Arabidopsis 为表示优化了。当 pH 与荧光消失在 pH 被降低, PEpHluorin (plant-solubility-modified 黄道 pHluorin ) 逐渐地失去荧光 6.2 并且 PRpHluorin (plant-solubility-modified ratiomatric pHluorin ) ,一个双刺激的传感器,允许精确大小。分隔空间特定的传感器被进一步熔化特定的排序的信号到 PEpHluorin 和 PRpHluorin 产生。我们的结果证明 cytosol 和原子核的 pH 是类似的(pH 7.3 和 7.2 ) 当 peroxisomes, mitochondrial 矩阵,和 plastidial 基质有碱的 pH 时。能分泌的小径的分隔空间揭示渐渐的使发酸,从 pH 跨越 7.1 在 endoplasmic 蜂窝胃(嗯) 到 pH 5.2 在液泡。令人惊讶地,在 trans-Golgi 网络(TGN ) 的 pH 和 multivesicular 身体(MVB ) 是,与 pH 6.3 和 6.2,相当类似。有 concanamycin A (ConcA ) 的 vacuolar 类型 H+-ATPase (V-ATPase ) 的抑制在 TGN 和液泡在 pH 引起了激烈的增加。总的来说, PEpHluorin 和 PRpHluorin 分别地是为在 vivo 的 pH 的可视化和 quantification 的优秀 pH 传感器。Jinbo Shen Yonglun Zeng Xiaohong Zhuang Lei Sun Xiaoqiang Yao Peter Pimpl Liwen Jiang 2013Molecular Plant2013,6,5:14
20Accurate Evaluation of Free-form Surface Profile Error Based on Quasi Particle Swarm Optimization Algorithm and Surface Subdivision显示文摘Although significant progress has been made in precision machining of free-form surfaces recently, inspection of such surfaces remains a difficult problem. In order to solve the problem that no specific standards for the verification of free-form surface profile are available, the profile parameters of free-form surface are proposed by referring to ISO standards regarding form tolerances and considering its complexity and non-rotational symmetry. Non-uniform rational basis spline(NURBS) for describing free-form surface is formulated. Crucial issues in surface inspection and profile error verification are localization between the design coordinate system(DCS) and measurement coordinate system(MCS) for searching the closest points on the design model corresponding to measured points. A quasi particle swarm optimization(QPSO) is proposed to search the transformation parameters to implement localization between DCS and MCS. Surface subdivide method which does the searching in a recursively reduced range of the parameters u and v of the NURBS design model is developed to find the closest points. In order to verify the effectiveness of the proposed methods, the design model is generated by NURBS and the measurement data of simulation example are generated by transforming the design model to arbitrary position and orientation, and the parts are machined based on the design model and are measured on CMM. The profile errors of simulation example and actual parts are calculated by the proposed method. The results verify that the evaluation precision of freeform surface profile error by the proposed method is higher 10%-22% than that by CMM software. The proposed method deals with the hard problem that it has a lower precision in profile error evaluation of free-form surface.WEN Xiulan ZHAO Yibing WANG Dongxia ZHU Xiaochun XUE Xiaoqiang 2013Chinese Journal of Mechanical Engineering2013,26,2:13
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