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394篇 您的检索式:作者名="Sun Hang"
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1Prevalence, risk factors, clinical course, and outcome of acute kidney injury in Chinese intensive care units: a prospective cohort study显示文摘WEN Ying JIANG Li XU Yuan QIAN Chuan-yun LI Shu-sheng QIN Tie-he CHEN Er-zhen LIN Jian-dong AI Yu- hang WU Da-wei WANG Yu-shan SUN Ren-hua HU Zhen-jie CAO Xiang-yuan ZHOU Fa-chun HE Zhen-yang ZHOU Li-hua AN You-zhong KANG Yan MA Xiao-chun YU Xiang-you ZHAO Ming-yan XI Xiu-ming DU Bin 2013Chinese Medical Journal2013,,23:40
2Andrographolide sulfonate ameliorates lipopolysaccharide-induced acute lung injury in mice by down-regulating MAPK and NF-κB pathways显示文摘Acute lung injury(ALI) or acute respiratory distress syndrome(ARDS) is a severe, lifethreatening medical condition characterized by widespread inflammation in the lungs, and is a significant source of morbidity and mortality in the patient population. New therapies for the treatment of ALI are desperately needed. In the present study, we examined the effect of andrographolide sulfonate, a water-soluble form of andrographolide(trade name: Xi-Yan-Ping Injection), on lipopolysaccharide(LPS)-induced ALI and inflammation. Andrographolide sulfonate was administered by intraperitoneal injection to mice with LPS-induced ALI. LPS-induced airway inflammatory cell recruitment and lung histological alterations were significantly ameliorated by andrographolide sulfonate. Protein levels of pro-inflammatory cytokines in bronchoalveolar lavage fluid(BALF) and serum were reduced by andrographolide sulfonate administration. m RNA levels of pro-inflammatory cytokines in lung tissue were also suppressed. Moreover, andrographolide sulfonate markedly suppressed the activation of mitogen-activated protein kinase(MAPK) as well as p65 subunit of nuclear factor-κB(NF-κB). In summary, these results suggest that andrographolide sulfonate ameliorated LPS-induced ALI in mice by inhibiting NF-κB and MAPK-mediated inflammatory responses. Our study shows that water-soluble andrographolide sulfonate may represent a new therapeutic approach for treating inflammatory lung disorders.Shuang Peng Nan Hang Wen Liu Wenjie Guo Chunhong Jiang Xiaoling Yang Qiang Xu Yang Sun 2016Acta Pharmaceutica Sinica B2016,6,3:38
3Origins and evolution of plant diversity in the Hengduan Mountains, China显示文摘1.Introduction The Hengduan Mountains region(HDM)in southwest China,one of the earth's 34 biodiversity hotspots,is characterized by its unique geology,dramatic topography,a climate where snow and below freezing temperatures can occur on any day of the year,by its location at elevations averaging between(1400e)2000 and4500(e5300)meters above sea level(m a.s.l.),and by one ofHang Sun Jianwen Zhang Tao Deng David E. Boufford 2017Plant Diversity2017,39,4:28
4Manufacturing Technology and Application Trends of Titanium Clad Steel Plates显示文摘Some of the major manufacturing processes and corresponding mechanical properties of titanium clad steel plates were analyzed, and the consequences of research, manufacturing, and application of titanium clad steel plates in both markets of China and overseas were also summarized. As an economical and environmentally friendly technology, the roll bonding process is expected to become the next-generation mainstream process for the manufacturing of titanium clad steel plate. Some of the crucial and most important technical problems of this particular process, including vacuum sealing technology, surface treatment process technology, application of a transition layer, and rolling process, were discussed along with the advantageous mechanical properties and life-cycle economy of these plates processed by this technology. Finally, the market needs, application trends, and requirements of titanium clad steel plate were also considered from industries of petrochemical, shipbuilding, marine, and electric power.Hang SU Xiao-bing LUO Feng CHAI Jun-chang SHEN Xin-jun SUN Feng LU 2015Journal of Iron and Steel Research(International)2015,22,11:18
5A holistic strategy for quality and safety control of traditional Chinese medicines by the “iVarious” standard system显示文摘An effective quality control system is the key to ensuring the quality, safety and efficacy of traditional Chinese medicines(TCMs). However, the current quality standard research lacks top-level design and systematic design,mostly based on specific technologies or evaluation methods. To resolve the challenges and questions of quality control of TCMs, a brand-new quality standard system, named 'iVarious', was proposed. The system comprises eight elements in a modular format. Meaning of every element was specifically illustrated via corresponding research instances. Furthermore, frankincense study was taken as an example for demonstrating standards and research process, based on the 'i Various' system. This system highlighted a holistic strategy for effectiveness,security, integrity and systematization of quality and safety control standards of TCMs. The establishment of'i Various' integrates multi-disciplinary technologies and progressive methods, basis elements and key points of standard construction. The system provides a novel idea and technological demonstration for regulation establishment of TCMs quality standards.Anzhen Chen Lei Sun Hang Yuan Aiying Wu Jingguang Lu Shuangcheng Ma 2017Journal of Pharmaceutical Analysis2017,7,5:16
6Molecular chaperones and hypoxic-ischemic encephalopathy显示文摘Hypoxic-ischemic encephalopathy(HIE) is a disease that occurs when the brain is subjected to hypoxia,resulting in neuronal death and neurological deficits,with a poor prognosis.The mechanisms underlying hypoxic-ischemic brain injury include excitatory amino acid release,cellular proteolysis,reactive oxygen species generation,nitric oxide synthesis,and inflammation.The molecular and cellular changes in HIE include protein misfolding,aggregation,and destruction of organelles.The apoptotic pathways activated by ischemia and hypoxia include the mitochondrial pathway,the extrinsic Fas receptor pathway,and the endoplasmic reticulum stress-induced pathway.Numerous treatments for hypoxic-ischemic brain injury caused by HIE have been developed over the last half century.Hypothermia,xenon gas treatment,the use of melatonin and erythropoietin,and hypoxic-ischemic preconditioning have proven effective in HIE patients.Molecular chaperones are proteins ubiquitously present in both prokaryotes and eukaryotes.A large number of molecular chaperones are induced after brain ischemia and hypoxia,among which the heat shock proteins are the most important.Heat shock proteins not only maintain protein homeostasis; they also exert anti-apoptotic effects.Heat shock proteins maintain protein homeostasis by helping to transport proteins to their target destinations,assisting in the proper folding of newly synthesized polypeptides,regulating the degradation of misfolded proteins,inhibiting the aggregation of proteins,and by controlling the refolding of misfolded proteins.In addition,heat shock proteins exert anti-apoptotic effects by interacting with various signaling pathways to block the activation of downstream effectors in numerous apoptotic pathways,including the intrinsic pathway,the endoplasmic reticulum-stress mediated pathway and the extrinsic Fas receptor pathway.Molecular chaperones play a key role in neuroprotection in HIE.In this review,we provide an overview of the mechanisms of HIE and discuss the various treatment strategies.Given their critical role in the disease,molecular chaperones are promising therapeutic targets for HIE.Cong Hua Wei-na Ju Hang Jin Xin Sun Gang Zhao 2017Neural Regeneration Research2017,12,1:15
7Aloe-emodin exerts cholesterol-lowering effects by inhibiting proprotein convertase subtilisin/kexin type 9 in hyperlipidemic rats显示文摘Hyperlipidemia(HPL)characterized by metabolic disorder of lipids and cholesterol is one of the important risk factors for cardiovascular diseases.Proprotein convertase subtilsin/kexin type 9(PCSK9)is a potent circulating regulator of LDL through its ability to induce degradation of the low-density lipoprotein cholesterol receptor(LDLR)in the lysosome of hepatocytes.Aloe-emodin(AE)is one of potentially bioactive components of Chinese traditionalmedicine Daming capsule.In this study we evaluated the HPL-lowering efficacy of AE in both in vivo and in vitro HPL models.High-fat diet-induced rats were treated with AE(100 mg/kg per day,ig)for 6 weeks.We found that AE administration significantly decreased the levels of total cholesterol(TC)and LDL in the serum and liver tissues.Moreover,AE administration ameliorated HPL-induced hepaticlipid aggregation.But AE administration did not significantly inhibit HMG-CoA reductase activity in the liver of HPL rats.A cellular model of HPL was established in human hepatoma(HepG2)cells treated with cholesterol(20 μg/mL)and 25-hydroxycholesterol(2 μg/mL),which exhibited markedly elevated cholesterol levels.The increased cholesterol levels could be reversed by subsequent treatment with AE(30 μM).In both the in vivo and in vitro HPL models,we revealed that AE selectively suppressed the stero-regulatory element-binding protein-2(SREBP-2)and hepatocyte nuclear factor(HNF)1α-mediated PCSK9 signaling,which in turn upregulated LDL receptor(LDLR)and promoted LDL uptake.This study demonstrates that AE reduces cholesterol content in HPL rats by inhibiting the hepatic PCSK9/LDLR pathway.Zhen-li Su Peng-zhou Hang Juan Hu Yu-yang Zheng Han-qi Sun Jing Guo Ke-yu Liu Zhi-min Du 2020Acta Pharmacologica Sinica2020,41,8:14
8A hybrid invisibility cloak based on integration of transparent metasurfaces and zero-index materials显示文摘The invisibility cloak,a long-standing fantastic dream for humans,has become more tangible with the development of metamaterials.Recently,metasurface-based invisibility cloaks have been proposed and realized with significantly reduced thickness and complexity of the cloaking shell.However,the previous scheme is based on reflection-type metasurfaces and is thus limited to reflection geometry.In this work,by integrating the wavefront tailoring functionality of transparent metasurfaces and the wave tunneling functionality of zero-index materials,we have realized a unique type of hybrid invisibility cloak that functions in transmission geometry.The principle is general and applicable to arbitrary shapes.For experimental demonstration,we constructed a rhombic double-layer cloaking shell composed of a highly transparent metasurface and a double-zero medium consisting of dielectric photonic crystals with Dirac cone dispersions.The cloaking effect is verified by both full-wave simulations and microwave experimental results.The principle also reveals exciting possibilities for realizing skin-thick ultrathin cloaking shells in transmission geometry,which can eliminate the need for spatially varying extreme parameters.Our work paves a path for novel optical and electromagnetic devices based on the integration of metasurfaces and metamaterials.Hongchen Chu Qi Li Bingbing Liu Jie Luo Shulin Sun Zhi Hong Hang Lei Zhou Yun Lai 2018Light(Science & Applications)2018,7,1:13
9Efficient generation of pink-fruited tomatoes using CRISPR/Cas9 system显示文摘Tomato(Solanum lycopersicum)is the leading vegetable crop worldwide and an essential component of a healthy diet(Lin et al.,2014;Du et al.,2017).Fruit color is regarded as one of the most important commercial traits in tomato(The Tomato Genome Consortium,2012).Consumers in different regions have different color preferences.For example,European andLei Deng Hang Wang Chuanlong Sun Qian Li Hongling Jiang Minmin Du Chang-Bao Li Chuanyou Li 2018Journal of Genetics and Genomics2018,45,1:13
10Is the East Asian flora ancient or not?显示文摘The East Asian flora(EAF) is a key biodiversity hotspot for understanding the origin and evolution of Northern Hemisphere floras, but there is an ongoing debate on whether it is a museum or a cradle for seed plants. Within the EAF, two main floras, the Sino-Himalayan Flora(mainly the Rhododendron Flora) and the Sino-Japanese Flora(mainly the Metasequoia Flora), have been recognized. Previous studies suggested that the EAF is ancient and the Metasequoia Flora is older than the Rhododendron Flora. To test this hypothesis, we synthesized molecular as well as fossil data on seed plants, focusing on the biogeographical origins and historical evolution of the EAF. We compared the ages of its two constituent floras, and examined the impact of the Asian monsoon and other environmental changes on the development of EAF through meta-analysis. Our results suggest that the EAF might be relatively young, with most of its clades originating since the Miocene. The Rhododendron Flora and the Metasequoia Flora are probably of a similar age. The formation and development of the Asian monsoon might have been the main factors that have driven the evolution of EAF. In the Rhododendron Flora, the north-south mountain chains increased the concentration of species and reduced extinction, and the barriers between the east and west have resulted in species differentiation, which triggered it to become a diversity center. The EAF appears to have multiple biogeographical origins, having closely affiliated not only with other floras in the Northern Hemisphere, but also with Gondwanan floras.Yong-Sheng Chen Tao Deng Zhuo Zhou Hang Sun 2018National Science Review2018,5,6:13
11Variants of the arachidonate 5-lipoxygenase-activating protein (ALOX5AP) gene and risk of ischemic stroke in Han Chinese of eastern China显示文摘Variants of the arachidonate 5-lipoxygenase-activating protein (ALOX5AP) gene have been suggested to play an important role in the pathogenesis of atherosclerosis and ischemic stroke.This study was aimed to explore the association of ALOX5AP variants with ischemic stroke risk in Han Chinese of eastern China.A total of 690 ischemic stroke cases and 767 controls were recruited.The subjects were further subtyped according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria.On the basis of that,two polymorphisms of the ALOX5AP gene (rs10507391 and rs12429692) were determined by TaqMan genotyping assay.In addition,plasma leukotriene B4 (LTB4) levels were analyzed in these subjects.There was no evidence of association between the two variants of ALOX5AP and the risk of ischemic stroke or its TOAST-subtypes.Haplotype analysis and stratification analysis according to sex,age,body mass index,hypertension,and diabetes also showed negative association.Analysis of LTB4 levels in a subset of cases and controls revealed that LTB4 levels were significantly higher in ischemic stroke cases than in the controls (70.06±14.75 ng/L vs 57.34±10.93 ng/L;P=0.000) and carriers of the T allele of the rs10507391 variant were associated with higher plasma LTB4 levels (P=0.000).The present study suggests there is no association of the two polymorphisms in the ALOX5AP gene with ischemic stroke risk in Han Chinese of eastern China.Gannan Wang Yao Wang Hao Sun Weijuan Cao Jing Zhang Hang Xiao Jinsong Zhang 2011The Journal of Biomedical Research2011,25,5:12
12Identification of microRNAs and messenger RNAs involved in human umbilical cord mesenchymal stem cell treatment of ischemic cerebral infarction using integrated bioinformatics analysis显示文摘In recent years,a large number of differentially expressed genes have been identified in human umbilical cord mesenchymal stem cell(hUMSC)transplants for the treatment of ischemic cerebral infarction.These genes are involved in various biochemical processes,but the role of microRNAs(miRNAs)in this process is still unclear.From the Gene Expression Omnibus(GEO)database,we downloaded two microarray datasets for GSE78731(messenger RNA(mRNA)profile)and GSE97532(miRNA profile).The differentially expressed genes screened were compared between the hUMSC group and the middle cerebral artery occlusion group.Gene ontology enrichment and pathway enrichment analyses were subsequently conducted using the online Database for Annotation,Visualization,and Integrated Discovery.Identified genes were applied to perform weighted gene co-suppression analyses,to establish a weighted co-expression network model.Furthermore,the protein-protein interaction network for differentially expressed genes from turquoise modules was built using Cytoscape(version 3.40)and the most highly correlated subnetwork was extracted from the protein-protein interaction network using the MCODE plugin.The predicted target genes for differentially expressed miRNAs were also identified using the online database starBase v3.0.A total of 3698 differentially expressed genes were identified.Gene ontology analysis demonstrated that differentially expressed genes that are related to hUMSC treatment of ischemic cerebral infarction are involved in endocytosis and inflammatory responses.We identified 12 differentially expressed miRNAs in middle cerebral artery occlusion rats after hUMSC treatment,and these differentially expressed miRNAs were mainly involved in signaling in inflammatory pathways,such as in the regulation of neutrophil migration.In conclusion,we have identified a number of differentially expressed genes and differentially expressed mRNAs,miRNA-mRNAs,and signaling pathways involved in the hUMSC treatment of ischemic cerebral infarction.Bioinformatics and interaction analyses can provide novel clues for further research into hUMSC treatment of ischemic cerebral infarction.Yin-Meng Qu Xin Sun Xiu-Li Yan Hang Jin Zhen-Ni Guo Yi Yang 2019Neural Regeneration Research2019,14,9:12
13Major advances in studies of the physical geography and living environment of China during the past 70 years and future prospects显示文摘The natural environment provides material essentials for human survival and development. The characteristics,processes, regional differentiation and forcing mechanisms of the elements of the natural environment(e.g. geomorphology,climate, hydrology, soil, etc.) are the main objects of research in physical geography. China has a complex natural environment and huge regional differentiation and therefore it provides outstanding reserach opportunities in physical geography. This review summarizes the most important developments and the main contributions of research in the physical geography and human living environment in China during the past 70 years. The major topics addressed are the uplift of the Tibetan Plateau and the evolution of its cryosphere, the development of fluvial systems, the acidification of the vast arid region of the Asian interior, variations in the monsoon and westerly climate systems on multiple timescales, the development of lakes and wetlands, the watershed system model, soil erosion, past human-environment interactions, biogeography, and physical geographic zonality. After briefly introducing international research developments, we review the history of research in physical geography in China, focusing on the major achievements and major academic debates, and finally we summarize the status of current research and the future prospects. We propose that in the context of the national demand for the construction of an ecological civilization, we should make full use of the research findings of physical geography, and determine the patterns and mechanisms of natural environmental processes in order to continue to promote the continued contribution of physical geography to national development strategies, and to further contribute to the theory of physical geography from a global perspective.Fahu CHEN Bojie FU Jun XIA Duo WU Shaohong WU Yili ZHANG Hang SUN Yu LIU Xiaomin FANG Boqiang QIN Xin LI Tingjun ZHANG Baoyuan LIU Zhibao DONG Shugui HOU Lide TIAN Baiqing XU Guanghui DONG Jingyun ZHENG Wei YANG Xin WANG Zaijun LI Fei Wang Zhenbo HU Jie WANG Jianbao LIU Jianhui CHEN Wei HUANG Juzhi HOU Qiufang CAI Hao LONG Ming JIANG Yaxian HU Xiaoming FENG Xingguo MO Xiaoyan YANG Dongju ZHANG Xiuhong WANG Yunhe YIN Xiaochen LIU 2019Science China Earth Sciences2019,62,11:11
14A novel cytotoxic neophysalin from Physalis alkekengi var.francheti显示文摘新 neophysalin,把 5 称为 α -hydroxy-25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A (1 ) ,与三另外的已知的 neophysalins 一起(2 – 4 ) 从 Physalis 冬季樱 L 的花萼被孤立。var。francheti (桅杆) Makino。1 的结构借助于 1D 和 2D NMR 被决定,紫外,红外和集体系列。对 PC-3 和 LNCaP 房间线在 vitro 加重 1 显示的有势力 cytotoxicities。Chu Hang Zhang Zheng Tao Wang Yi Ping Yang Qi Shi Sun 2009Chinese Chemical Letters2009,20,11:9
15A telomere-to-telomere gap-free reference genome of watermelon and its mutation library provide important resources for gene discovery and breeding显示文摘Watermelon,Citrullus lanatus,is the world's third largest fruit crop.Reference genomes with gaps and a narrow genetic base hinder functional genomics and genetic improvement of watermelon.Here,we report the assembly of a telomere-to-telomere gap-free genome of the elite watermelon inbred line G42 by incorporating high-coverage and accurate long-read sequencing data with multiple assembly strategies.All 11 chromosomes have been assembled into single-contig pseudomolecules without gaps,representing the highest completeness and assembly quality to date.The G42 reference genome is 369321829 bp in length and contains 24205 predicted protein-coding genes,with all 22 telomeres and 11 centromeres characterized.Furthermore,we established a pollen-EMS mutagenesis protocol and obtained over 200000M1 seeds from G42.In a sampling pool,48 monogenic phenotypic mutations,selected from 223M1and 78 M2 mutants with morphological changes,were confirmed.The average mutation density was 1 SNP/1.69Mband1 indel/4.55 Mb per M1 plant and 1SNP/1.08Mb and 1 indel/6.25 Mb per M2 plant.Taking advantage of the gap-free G42 genome,8039 mutations from 32 plants sampled from M1 and M2 families were identified with 100%accuracy,whereas only 25% of the randomly selected mutations identified using the 97103v2 reference genome could be confirmed.Using this library and the gap-free genome,two genes responsible for elongated fruit shape and male sterility(CiMs1)were identified,both caused by a single basechange from G to A.The validated gap-free genome and its EMS mutation library provide invaluable resources for functional genomics and genetic improvement of watermelon.Yun Deng Shoucheng Liu Yilin Zhang Jingsheng Tan Xiaopeng Li Xiao Chu Binghua Xu Yao Tian Yudong Sun Bosheng Li YunbiXu Xing Wang Deng Hang He Xingping Zhang 2022Molecular Plant2022,15,8:9
16Clinical application of serial operations with preserving spleen显示文摘AIM: To evaluate the clinical application of serial operations with preservation of spleen.METHODS: Serial operations with preserving spleen were performed on 211 cases in our hospital from 1980 to 2000.The patient's age ranged from 13 to 56 years, averaging 3years. Diseases included splenic injury in 171 cases, portal hypertension in 9 cases, splenic cyst in 10 cases, and the lesion of pancreatic body and tail in 21 cases.RESULTS: All the cases were cured, and 129 patients were followedup from 3 months to 3 years with the leukocyte phagocytosis test, detection of immunoglubin, CT, 99mTc scanning and ultrasonogrsphy. The results were satisfactory.CONCLUSION: The operations with preserving spleen were safe, feasible, and worth of clinical application.Hong-Chi Jiang~1 Bei Sun~1 Hai-Quan Qiao~1 Jun Xu~1 Da-Xun Piao~1 Hang Yin~2 1 Department of General Surgery,First Clinical Hospital,Harbin Medical University,Harbin 150001,China2 Department of General Surgery,Heilongjiang Provincial Hospital,Harbin 150001,China 2001World Journal of Gastroenterology2001,7,6:8
17Impending HRT wave precursors to the Wenchuan M_s8.0 earthquake and methods of earthquake impending prediction by using HRT wave显示文摘We deployed four geo-electric monitoring stations in Sichuan and Yunnan provinces from 2004, using the new generation of equipment (PS-100) and technologies to capture the HRT wave earthquake precursor. Before the Wenchuan Ms8.0 earthquake, we recorded the HRT wave precursor at the only operating station in Hongge (HG, Δ=465 km) and found that significant impending signal had been recorded at the station in the early morning ( 0―5 am) of 12th of May, 2008. The precursor for this earthquake is consistent with precursors recorded for other strong earthquakes. The measured physical properties (geo-resistivity and telluric-current) show tidal wave period oscillations from several days to several months before the earthquakes and the amplitude of such HT oscillation increases significantly towards the occurrence of an earthquake. These HT and RT waves from the epicenter have a causal relationship with the earthquakes that happened several days later. The arrival time of two RT waves is proportional to the distance from the station to the epicenter. The estimated natural decay of the amplitude is correlated with the natural period (T0) of the earthquake fault, which is proportional to the fault length. From this relationship, we can predict the earthquake magnitude. For magnitude 6―9 earthquakes, the natural period is about 1―6 hours. Such oscillation comes from the epicenter area and they can propagate several thousand kilometers in the Earth's crust. Before a strong earthquake in the shallow crust, the conductive pore fluid will experience major changes before the fault rapture. Such fluid change will emit an oscillation in the pore fluid pressure. This is the mechanism for the HRT wave generation. Since the China Earthquake Administration funded the HRT wave short-term earth-quake prediction project in 2003, the first record of HRT precursor wave has been recorded from the 2004-12-26 Sumatra Mw9.0 earthquake with the largest epicentre distance Δ=2900 km. Thereafter, we have captured HRT waves from more than twenty strong earthquakes, which are well-matched and show repeatability, consistency and regularity. All our observation with the HRT waves demonstrate that HRT wave precursors to earthquakes indeed exist. Strong earthquakes can be predicted and short-term and impending earthquake prediction is achievable in the very near future. From all the observations, including the ones at HG station from Wenchuan Ms8.0 earthquake, we conclude that using HRT wave to predict earthquakes is feasible.QIAN FuYe ZHAO BiRu QIAN Wei ZHAO Jian HE ShiGen ZHANG HongKui LI ShiYu LI ShaoKun YAN GuLiang WANG ChengMin SUN ZhenKai ZHANG DongNing LU Jun ZHANG Ping YANG GuoJun SUN JiaLin GUO ChunSheng TANG YuXiong XU JianMing XIA KunTao JU Hang YIN BangHong LI Ming YANG DongSheng QI WeiLuo HE TaiMing GUAN HuaPing ZHAO YuLin 2009Science China Earth Sciences2009,52,10:8
18Asynchronous Brain-Computer Interface Shared Control of Robotic Grasping显示文摘The control of a high Degree of Freedom(DoF) robot to grasp a target in three-dimensional space using Brain-Computer Interface(BCI) remains a very difficult problem to solve. Design of synchronous BCI requires the user perform the brain activity task all the time according to the predefined paradigm; such a process is boring and fatiguing. Furthermore, the strategy of switching between robotic auto-control and BCI control is not very reliable because the accuracy of Motor Imagery(MI) pattern recognition rarely reaches 100%. In this paper, an asynchronous BCI shared control method is proposed for the high DoF robotic grasping task. The proposed method combines BCI control and automatic robotic control to simultaneously consider the robotic vision feedback and revise the unreasonable control commands. The user can easily mentally control the system and is only required to intervene and send brain commands to the automatic control system at the appropriate time according to the experience of the user. Two experiments are designed to validate our method: one aims to illustrate the accuracy of MI pattern recognition of our asynchronous BCI system; the other is the online practical experiment that controls the robot to grasp a target while avoiding an obstacle using the asynchronous BCI shared control method that can improve the safety and robustness of our system.Wenchang Zhang Fuchun Sun Hang Wu Chuanqi Tan Yuzhen Ma 2019Tsinghua Science and Technology2019,24,3:8
19Multi-scale simulation of single crystal hollow turbine blade manufactured by liquid metal cooling process显示文摘Liquid metal cooling(LMC) process as a powerful directional solidification(DS) technique is prospectively used to manufacture single crystal(SC) turbine blades. An understanding of the temperature distribution and microstructure evolution in LMC process is required in order to improve the properties of the blades. For this reason, a multi-scale model coupling with the temperature field, grain growth and solute diffusion was established. The temperature distribution and mushy zone evolution of the hollow blade was simulated and discussed.According to the simulation results, the mushy zone might be convex and ahead of the ceramic beads at a lower withdrawal rate, while it will be concave and laggard at a higher withdrawal rate, and a uniform and horizontal mushy zone will be formed at a medium withdrawal rate. Grain growth of the blade at different withdrawal rates was also investigated. Single crystal structures were all selected out at three different withdrawal rates.Moreover, mis-orientation of the grains at 8 mm/min reached ~30°, while it was ~5° and ~15° at 10 mm/min and 12 mm/min, respectively. The model for predicting dendritic morphology was verified by corresponding experiment. Large scale for 2D dendritic distribution in the whole sections was investigated by experiment and simulation, and they presented a well agreement with each other.Xuewei Yan Hang Zhang Ning Tang Changbo Sun Qingyan Xu Baicheng Liu 2018Progress in Natural Science:Materials International2018,28,1:8
20Phylogenetic pattern of alpine plants along latitude and longitude in Hengduan Mountains Region显示文摘To detect the horizontal pattern of phylogenetic structure shown by alpine plants, we measured phylogenetic structure using net related index(NRI) and net nearest taxon index(NTI), and analyzed the phylogenetic structure patterns of alpine plants along longitude, latitude and environmental gradients in the Hengduan Mountains Region(HDMR). Our results show that: 1) the phylogenetic structure tended to cluster with increasing latitude and longitude; 2) for NRI, latitude was closer related than longitude,while for NTI, longitude was closer related than latitude, though they both not significantly relate to NTI.The phylogenetic structure tended towards overdispersion in the southern HDMR, with good climate conditions of higher mean annual temperature and more mean annual precipitation. In contrast, with harsh climate conditions of lower mean annual temperature and less mean annual precipitation, the increasing environmental stress led to phylogenetic clustering in the northern HDMR. The results highlighted that in the alpine region of HDMR, environmental filters and geographical isolation had a great effect on the latitudinal and longitudinal alpine species distribution, respectively.Xinhui Li Hang Sun 2017Plant Diversity2017,39,1:8
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