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1Current applications of adipose-derived stem cells and their future perspectives显示文摘Adult stem cells have a great potential to treat various diseases. For these cell-based therapies, adipose-derived stem cells(ADSCs) are one of the most promising stem cell types, including embryonic stem cells(ESCs) and induced pluripotent stem cells(iPSCs). ESCs and iPSCs have taken center stage due to their pluripotency. However, ESCs and iPSCs have limitations in ethical issues and in identification of characteristics, respectively. Unlike ESCs and iPSCs, ADSCs do not have such limitations and are not only easily obtained but also uniquely expandable. ADSCs can differentiate into adipocytes, osteoblasts, chondrocytes, myocytes and neurons under specific differentiation conditions, and these kinds of differentiation potential of ADSCs could be applied in regenerative medicine e.g., skin reconstruction, bone and cartilage formation, etc. In this review, the current status of ADSC isolation, differentiation and their therapeutic applications are discussed.Eun-Hee Kim Chan Yeong Heo 2014World Journal of Stem Cells2014,6,1:19
2浅谈电力系统配电自动化及其对故障的处理显示文摘针对电力系统配电自动化系统的过程控制情况、功能、特点进行分析,以典型实例分析配电自动化的实际应用,说明配电自动化技术通过对配电网的远方监控和自动控制,具备独特的故意定位、故障隔离和供电恢复功能,对配电网安全、可靠、经济、优质、高效运行有着十分广阔的应用前景。李金英 2003成都工业学院学报2003,15,4:18
3Distributed processing based fault location,isolation,and service restoration method for active distribution network显示文摘Active distribution network(ADN)is a solution for power system with interconnection of distributed energy resources(DER),which may change the network operation and power flow of traditional power distribution network.However,in some circumstances the malfunction of protection and feeder automation in distribution network occurs due to the uncertain bidirectional power flow.Therefore,a novel method of fault location,isolation,and service restoration(FLISR)for ADN based on distributed processing is proposed in this paper.The differential-activated algorithm based on synchronous sampling for feeder fault location and isolation is studied,and a framework of fault restoration is established for ADN.Finally,the effectiveness of the proposed algorithm is verified via computer simulation of a case study for active distributed power system.Jiaming WENG Dong LIU Ning LUO Xueyong TANG 2015Journal of Modern Power Systems and Clean Energy2015,3,4:16
4Speciation with gene flow via cycles of isolation and migration:insights from multiple mangrove taxa显示文摘Allopatric speciation requiring an unbroken period of geographical isolation has been the standard model of neo-Darwinism. While doubts have been repeatedly raised, strict allopatry without any gene flow remains a plausible mechanism in most cases. To rigorously reject strict allopatry, genomic sequences superimposed on the geological records of a well-delineated geographical barrier are necessary. The Strait of Malacca,narrowly connecting the Pacific and Indian Ocean coasts, serves at different times either as a geographical barrier or a conduit of gene flow for coastal/marine species. We surveyed 1700 plants from 29 populations of 5 common mangrove species by large-scale DNA sequencing and added several whole-genome assemblies. Speciation between the two oceans is driven by cycles of isolation and gene flow due to the fluctuations in sea level leading to the opening/closing of the Strait to ocean currents. Because the time required for speciation in mangroves is longer than the isolation phases, speciation in these mangroves has proceeded through many cycles of mixing-isolation-mixing, or MIM, cycles. The MIM mechanism, by relaxing the condition of no gene flow, can promote speciation in many more geographical features than strict allopatry can. Finally, the MIM mechanism of speciation is also efficient, potentially yielding mn(m > 1) species after n cycles.Ziwen He Xinnian Li Ming Yang Xinfeng Wang Cairong Zhong Norman C.Duke Chung-I Wu Suhua Shi 2019National Science Review2019,6,2:14
5Isolation and identification of bacteria responsible for simultaneous anaerobic ammonium and sulfate removal显示文摘Sulfate-dependent anaerobic ammonium oxidation is a novel biological reaction,in which ammonium is oxidized with sulfate as the electron acceptor under anoxic conditions.Ammonium and sulfate are cosmopolitan chemical species which are an integral part of the global nitrogen and sulfur cycles.A detailed exploration of sulfate-dependent anaerobic ammonium oxidation is quite practical.In this work,a bacterial strain named ASR has been isolated from an anaerobic ammonia and sulfate removing reactor working under steady-state.On the basis of electron microscopy,physiological tests and 16S rDNA phylogenetic sequence analysis,the strain ASR is found to be related to Bacillus benzoevorans.According to the biological carbon source utilization test,the strain ASR could use many carbon sources.Its optimum pH value and temperature were 8.5 and 30 °C,respectively.The test proves that the strain ASR is able to use sulfate to oxidize ammonia anaerobically.The maximum ammonia and sulfate removal rates were 44.4% and 40.0%,respectively.The present study provided biological evidence for the confirmation and development of sulfate-dependent anaerobic ammonium oxidation and brought new insights into the global nitrogen and sulfur cycles.Cai, Jing Jiang, Jian Xiang Zheng, Ping 2010Science China Chemistry2010,53,3:12
6CHEMICAL CONSTITUENTS OF LONICERA MACRANTHOIDES HAND.-MAZZ Ⅰ.STRUCTURE OF MACRANTHOISIDE I显示文摘A new bisdesmosidic triterpene saponin,macranthoiside I,wasisolated from L.macranthoides.Its structure was determinedby chemical degradation and spectroscopic analysis.Min CHEN Si Qi LUO Hui Ting LI Shanghai Institute of Pharmaceutical Industry Shanghai,200040 1990Chinese Chemical Letters1990,1,3:11
7Study of the seismic performance of expansion double spherical seismic isolation bearings for continuous girder bridges显示文摘The development of an expansion double spherical seismic isolation (DSSI) bearing by modifying the fixed DSSI bearing is described in this paper. The expansion DSSI bearing is characterized by its good energy dissipation and horizontal displacement capacity and has been successfully integrated into the seismic design of several important engineering projects in China. It is envisioned to be used as a substitute for ordinary expansion bearings in continuous girder bridges to distribute the longitudinal earthquake action among all the piers. Its development, configuration and working mechanism are introduced first. The test method and the seismic performance of an expansion DSSI bearing are then briefly described. A theoretical analysis followed by a numerical analysis for an actual four-span continuous girder bridge are provided as an example, and it is concluded that the expansion DSSI bearing can be integrated into the seismic design of continuous girder bridges.Peng, Tianbo Yu, Xuntao Wang, Zhennan Han, Lei 2012Earthquake Engineering and Engineering Vibration2012,11,2:11
8Combination of Model-based Observer and Support Vector Machines for Fault Detection of Wind Turbines显示文摘Support vector machines and a Kalman-like observer are used for fault detection and isolation in a variable speed horizontalaxis wind turbine composed of three blades and a full converter. The support vector approach is data-based and is therefore robust to process knowledge. It is based on structural risk minimization which enhances generalization even with small training data set and it allows for process nonlinearity by using flexible kernels. In this work, a radial basis function is used as the kernel. Different parts of the process are investigated including actuators and sensors faults. With duplicated sensors, sensor faults in blade pitch positions,generator and rotor speeds can be detected. Faults of type stuck measurements can be detected in 2 sampling periods. The detection time of offset/scaled measurements depends on the severity of the fault and on the process dynamics when the fault occurs. The converter torque actuator fault can be detected within 2 sampling periods. Faults in the actuators of the pitch systems represents a higher difficulty for fault detection which is due to the fact that such faults only affect the transitory state(which is very fast) but not the final stationary state. Therefore, two methods are considered and compared for fault detection and isolation of this fault: support vector machines and a Kalman-like observer. Advantages and disadvantages of each method are discussed. On one hand, support vector machines training of transitory states would require a big amount of data in different situations, but the fault detection and isolation results are robust to variations in the input/operating point. On the other hand, the observer is model-based, and therefore does not require training, and it allows identification of the fault level, which is interesting for fault reconfiguration. But the observability of the system is ensured under specific conditions, related to the dynamics of the inputs and outputs. The whole fault detection and isolation scheme is evaluated using a wind turbine benchmark with a real sequence of wind speed.Nassim Laouti Sami Othman Mazen Alamir Nida Sheibat-Othman 2014International Journal of Automation and computing2014,11,3:11
9High frequencies of HGV and TTV infections in blood donors in Hangzhou显示文摘ALM To determine the frequencies of HGV and TTVinfections in blood donors in Hangzhou.METHODS RT-nested PCR for HGV RNA detection and semi-nested PCR for TTV DNA detection in the sera from 203 blood donors, and nucleotide sequence analysis were performed.``RESULTS Thirty-two ( 15.8%) and 30 (14.8%) of the 203serum samples were positive for HGV RNA and TTV DNA,respectively. And 5 (2.5%) of the 203 serum samples were detectable for both HGV RNA and TTV DNA.Homology of the nucleotide sequences of HGV RT-nested PCR products and TTV semi-nested PCR products from 3serum samples compared with the reported HGV and TTV sequences was 89.36%. 87.94%, 88.65% and 63.51%.65.77% and 67.12%. respectively.``CONCLUSION The infection rates of HGV and/or TTV inblood donors are relatively high. and to establish HGV and TTV examinations to screen blood donors is needed for transfusion security. The genomic heterogeneity of TTV or HGV is present in the isolates from different areas.Jie Yan~1 Li-Li Chen~2 Yi-Hui Luo~1 Ya-Fei Mao~1 Meng He~1 1 Department of Pathogenic Biology,Medical School of Zhejiang University,Hangzhou 310006,Zhejiang Province,China2 Department of Stomatology,The Second Affiliated Hospital,Medical School of Zhejiang University,Hangzhou 310009,Zhejiang Province,China 2001World Journal of Gastroenterology2001,7,5:11
10Performance of sand and shredded rubber tire mixture as a natural base isolator for earthquake protection显示文摘The performance of a well-designed layer of sand, and composites like layer of sand mixed with shredded rubber tire(RSM) as low cost base isolators, is studied in shake table tests in the laboratory. The building foundation is modeled by a 200 mm by 200 mm and 40 mm thick rigid plexi-glass block. The block is placed in the middle of a 1m by 1m tank filled with sand. The selected base isolator is placed between the block and the sand foundation. Accelerometers are placed on top of the footing and foundation sand layer. The displacement of the footing is also measured by LVDT. The whole setup is mounted on a shake table and subjected to sinusoidal motions with varying amplitude and frequency. Sand is found to be effective only at very high amplitude(> 0.65 g) of motions. The performance of a composite consisting of sand and 50% shredded rubber tire placed under the footing is found to be most promising as a low-cost effective base isolator.Srijit Bandyopadhyay Aniruddha Sengupta G.R.Reddy 2015Earthquake Engineering and Engineering Vibration2015,14,4:10
11番茄内生细菌的分离及其促生活性研究(英文)显示文摘[Objective] The study aimed to investigate the growth-promoting activities of endophytic bacteria from tomato plants.[Method]The endophytic bacteria isolated from different tissues of tomato plants were analyzed for the effects of their growth-promoting activities on the germination and growth of tomato plants.The bacteria with growth-promoting activity were preliminarily identified.[Result]Totally 59 endophytic bacterial strains were isolated from roots and stems of tomatoes,of which 4 showed significantly growth-promoting activity to germination and growth of tomato.The results suggest that these strains are endowed with the potential capability of growth-promoting.[Conclusion]The endophytic bacteria with growth-promoting activity were found among the isolates from tomato plants.This provided a good foundation for utilization of these bacteria with growth-promoting activity.张立新 宋江华 刘慧平 2008Agricultural Science & Technology2008,9,5:10
12SALVIANOLIC ACID G,A CAFFEIC ACID DIMER WITH A NOVEL TETRACYCLIC SKELETON显示文摘Salvianolic acid G,a caffeic acid dimer with a noveltetracyclic skeleton was isolated from the roots of Salviamiltiorrhiza.Its structure was elucidated by chemical and spectralanalysis,especially by 2D NMR analysis.Chun Bo AI Lian Niang LI Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing 100050,China 1991Chinese Chemical Letters1991,2,1:10
13基于车联网数据挖掘的驾驶员行为分析显示文摘随着汽车数量持续增加,车与路的矛盾日益突出,由此引发了交通运输和管理问题.而智能交通技术和车联网技术是解决交通拥堵和管理问题的有效途径.因此,运用数据挖掘的方法,使用isolation forest算法和SOM算法对车联网技术采集的交通数据进行预处理并提取特征值,再通过K-mesns聚类算法归类并添加标签,最后通过BP神经网络构建分类器,实现了对驾驶员驾驶行为的分类和评价,实例计算结果表明,该算法能客观、有效的评价驾驶员驾驶行为,对交管部门、汽车营运企业有具有一定参考价值.郑恒杰 熊昕 张上 2019信息通信2019,32,8:10
14POWER FLOW ANALYSIS FOR A NEW ISOLATION SYSTEM-FLEXIBLE FLOATING RAFT显示文摘POWERFLOWANALYSISFORANEWISOLATIONSYSTEM-FLEXIBLEFLOATINGRAFTPOWERFLOWANALYSISFORANEWISOLATIONSYSTEM-FLEXIBLEFLOATINGRAFTXiong...Xiong Yeping Song Kongjie Wang Chun Han Yuchang( Shandong University of Technology) 1996Chinese Journal of Mechanical Engineering1996,9,3:10
15Application of isolation forest to extract multivariate anomalies from geochemical exploration data显示文摘Constructing a statistical model that best fits the background is a key step in geochemical anomaly identification. But the model is hard to be constructed in situations where the sample population has unknown and/or complex distribution. Isolation forest is an outlier detection approach that explicitly isolates anomaly samples rather than models the population distribution. It can extract multivariate anomalies from huge-sized high-dimensional data with unknown population distribution. For this reason,we tentatively applied the method to identify multivariate anomalies from the stream sediment survey data of the Lalingzaohuo district,an area with a complex geological setting,in Qinghai Province in China. The performance of the isolation forest algorithm in anomaly identification was compared with that of a continuous restricted Boltzmann machine. The results show that the isolation forest model performs superiorly to the continuous restricted Boltzmann machine in multivariate anomaly identification in terms of receiver operating characteristic curve,area under the curve,and data-processing efficiency. The anomalies identified by the isolation forest model occupy 19% of the study area and contain 82% of the known mineral deposits,whereas the anomalies identified by the continuous restricted Boltzmann machine occupy 35% of the study area and contain 88% of the known mineral deposits. It takes 4. 07 and 279. 36 seconds respectively handling the dataset using the two models. Therefore,isolation forest is a useful anomaly detection method that can quickly extract multivariate anomalies from geochemical exploration data.WU Wei CHEN Yongliang 2018Global Geology2018,21,1:9
16The molecular and evolutionary basis of reproductive isolation in plants显示文摘Reproductive isolation is defined as processes that prevent individuals of different populations from mating, survival or producing fertile offspring. Reproductive isolation is critical for driving speciation and maintaining species identity, which has been a fundamental concern in evolutionary biology. In plants,reproductive isolation can be divided into prezygotic and postzygotic reproductive barriers, according to its occurrence at different developmental stages. Postzygotic reproductive isolation caused by reduced fitness in hybrids is frequently observed in plants, which hinders gene flow between divergent populations and has substantial effects on genetic differentiation and speciation, and thus is a major obstacle for utilization of heterosis in hybrid crops. During the past decade, China has made tremendous progress in molecular and evolutionary basis of prezygotic and postzygotic reproductive barriers in plants. Present understandings in reproductive isolation especially with new data in the last several years well support three evolutionary genetic models, which represent a general mechanism underlying genomic differentiation and speciation. The updated understanding will offer new approaches for the development of wide-compatibility or neutral varieties, which facilitate breeding of hybrid rice as well as other hybrid crops.Yidan Ouyang Qifa Zhang 2018Journal of Genetics and Genomics2018,45,11:9
17Synthesis, isolation and characterization of methyl levulinate from cellulose catalyzed by extremely low concentration acid显示文摘A direct synthesis of methyl levulinate from cellulose alcoholysis in methanol medium under mild condition(180 210 C)catalyzed by extremely low concentration sulfuric acid(0.01 mol/L)and the product isolation were developed in this study.Effects of different process variables towards the catalytic performance were performed as a function of reaction time.The results indicated that sulfuric acid concentration,temperature and initial cellulose concentration had significant effects on the synthesis of methyl levulinate.An optimized yield of around 50%was achieved at 210 C for 120 min with sulfuric acid concentration of 0.01 mol/L and initial cellulose concentration below 100 g/L.The resulting product mixture was isolated by a distillation technique that combines an atmospheric distillation with a vacuum distillation where n-dodecane was added to help distill the heavy fraction.The light fraction including mainly methanol could be reused as the reaction medium without any substantial change in the yield of methyl levulinate.The chemical composition and structural of lower heavy fraction were characterized by GC/MS,FTIR,1H-NMR and13C-NMR techniques.Methyl levulinate was found to be a major ingredient of lower heavy fraction with the content over 96%.This pathway is efficient,environmentally benign and economical for the production of pure levulinate esters from cellulose.Hui Li Lincai Peng Lu Lin Keli Chen Heng Zhang 2013Journal of Energy Chemistry2013,22,6:9
18Transplantation of stem cells from human exfoliated deciduous teeth for bone regeneration in the dog mandibular defect显示文摘AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been isolated 5 years ago from human exfoliated deciduous teeth. The undifferentiated stem cells were seeded into mandibular bone through-andthrough defects of 4 dogs. Similar defects in control group were filled with cell-free collagen scaffold. After 12 wk, biopsies were taken and morphometric analysis was performed. The percentage of new bone formation and foreign body reaction were measured in each case. The data were subject to statistical analysis using the Mann-Whitney U and Kruskalwalis statistical tests. Differences at P < 0.05 was considered as significant level.RESULTS: There were no significant differences between control and SHED-seeded groups in connective tissue(P = 0.248), woven bone(P = 0.248) and compact bone(P = 0.082). There were not any side effects in transplanted SHED group such as teratoma or malignancy and abnormalities in this period.CONCLUSION: SHEDs which had been isolated and characterized 5 years ago and stored with cryopreservation banking were capable of proliferation and osteogenesis after 5 years, and no immune response was observed after three months of seeded SHEDs.Ali Behnia Abbas Haghighat Ardeshir Talebi Nosrat Nourbakhsh Fariba Heidari 2014World Journal of Stem Cells2014,6,4:9
19Molecular mechanisms of hybrid sterility in rice显示文摘Hybrid sterility presents a major bottleneck in hybrid crop breeding and causes postzygotic reproductive isolation in speciation.Here, we summarize the current understanding of the genetics of rice hybrid sterility and highlight new advances in deciphering the molecular basis of the major genetic loci for hybrid sterility in rice. We also discuss practical strategies for overcoming reproductive barriers to utilize hybrid vigor in inter-specific and inter-subspecific hybrid rice breeding.Yongyao Xie Rongxin Shen Letian Chen Yao-Guang Liu 2019Science China(Life Sciences)2019,62,6:8
20Mechanical properties and associated seismic isolation effects of foamed concrete layer in rock tunnel显示文摘Foamed concrete has a good energy absorption capability and can be used as seismic isolation material for tunnels. This study aims to investigate the mechanical properties and associated seismic isolation effects of foamed concrete layer in rock tunnel. For this, a series of uniaxial/triaxial compression tests was conducted to understand the effects of concrete density, confining stress and strain rate on the mechanical properties of foamed concrete. The direct shear tests were also performed to investigate the effects of concrete density and normal stress on the nonlinear behaviors of foamed concrete layer-lining interface. The test results showed that the mechanical properties of foamed concrete are significantly influenced by the concrete density. The foamed concrete also has high volumetric compressibility and strain-rate dependence. The peak stress. residual stress. shear stiffness and residual friction coefficient of the foamed concrete layer-lining interface are influenced by the foamed concrete density and normal stress applied. Then, a crushable foam constitutive model was constructed using ABAQUS software and a composite exponential model was also established to study the relationship between shear stress and shear displacement of the interface, in which their parameters were fitted based on the experimental results. Finally, a parametric analysis using the finite element method(FEM) was conducted to understand the influence of foamed concrete layer properties on the seismic isolation effect, including the density and thickness of the layer as well as the shear stiffness and residual friction coefficient of the interface. It was revealed that lower density and greater thickness in addition to smaller shear stiffness or residual friction coefficient of the foamed concrete layer could yield better seismic isolation effect, and the influences of the first two tend to be more significant.Shaosen Ma Weizhong Chen Wusheng Zhao 2019Journal of Rock Mechanics and Geotechnical Engineering2019,11,1:8
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