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1Preface显示文摘We are very proud and honored to have been entrusted to guest edit this special issue entitled'Mobile Ad Hoc and Sensor Systems',for the Journal of Computer Science and Technology,the leading Chinese journal in the area of computing.Our main goal was to put together a strong issue emphasizing quality and relevance to current interests in this important field.Our goal was to attract leading researchers in this'hot'field of researchLi, Xiao-Dong Luo, Wen-Jian Yao, Xin 2008Journal of Computer Science & Technology2008,23,1:91
2A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus(2019-nCoV) infected pneumonia(standard version)显示文摘In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province;and then named '2019 novel coronavirus(2019-nCoV)' by the World Health Organization(WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world’s attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development;we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control(including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.Ying-Hui Jin Lin Cai Zhen-Shun Cheng Hong Cheng Tong Deng Yi-Pin Fan Cheng Fang Di Huang Lu-Qi Huang Qiao Huang Yong Han Bo Hu Fen Hu Bing-Hui Li Yi-Rong Li Ke Liang Li-Kai Lin Li-Sha Luo Jing Ma Lin-Lu Ma Zhi-Yong Peng Yun-Bao Pan Zhen-Yu Pan Xue-Qun Ren Hui-Min Sun Ying Wang Yun-Yun Wang Hong Weng Chao-Jie Wei Dong-Fang Wu Jian Xia Yong Xiong Hai-Bo Xu Xiao-Mei Yao Yu-Feng Yuan Tai-Sheng Ye Xiao-Chun Zhang Ying-Wen Zhang Yin-Gao Zhang Hua-Min Zhang Yan Zhao Ming-Juan Zhao Hao Zi Xian-Tao Zeng Yong-Yan Wang Xing-Huan Wang 2020Military Medical Research2020,7,1:161
3Mapping wetland changes in China between 1978 and 2008显示文摘Four wetland maps for all China have been produced,based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and validated by substantial field investigation in 2009.Based on these maps,we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years.(i) There were about 324097 km 2 of wetlands in 2008,for which inland marshes or swamps were the most common wetland type (35%),with lakes (26%) second.Most of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2008,China's wetland area continually and significantly decreased,by about 33% based on changes in the wetland map.This was in sharp contrast to the increase in artificial wetlands,which increased by about 122%.Inland marshes accounted for the main loss of total wetlands from 1978 to 2000.From 2000 through 2008,riverine and lacustrine wetlands constituted the main wetland loss.Fortunately however,the rate of wetland loss decreased from 5523 to 831 km 2 /a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 years.From 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into non-wetlands.However,the ratio declined to 86% from 1990 to 2000,and to 77% from 2000 to 2008.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such changes.Tibet was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since 1990.Increased economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased.NIU ZhenGuo ZHANG HaiYing WANG XianWei YAO WenBo ZHOU DeMin ZHAO KuiYi ZHAO Hui LI NaNa HUANG HuaBing LI CongCong YANG Jun LIU CaiXia LIU Shuang WANG Lin LI Zhan YANG ZhenZhong QIAO Fei ZHENG YaoMin CHEN YanLei SHENG YongWei GAO XiaoHong ZHU WeiHong WANG WenQing WANG Hong WENG YongLing ZHUANG DaFang LIU JiYuan LUO ZhiCai CHENG Xiao GUO ZiQi GONG Peng 2012Chinese Science Bulletin2012,57,22:51
4Assessment of candidate plant DNA barcodes using the Rutaceae family显示文摘DNA barcoding is a rapidly developing frontier technology that is gaining worldwide attention.Here,seven regions (psbA-trnH,matK,ycf5,rpoC1,rbcL,ITS2,and ITS) with potential for use as DNA barcodes were tested for their ability to identify 300 samples of 192 species from 72 genera of the family Rutaceae.To evaluate each barcode’s utility for species authentication,PCR amplification efficiency,genetic divergence,and barcoding gaps were assessed.We found that the ITS2 region exhibited the highest inter-specific divergence,and that this was significantly higher than the intra-specific variation in the 'DNA barcoding gap' assessment and Wilcoxon two-sample tests.The ITS2 locus had the highest identification efficiency among all tested regions.In a previous study,we found that ITS2 was able to discriminate a wide range of plant taxa,and here we confirmed that ITS2 was also able to discriminate a number of closely related species.Therefore,we propose that ITS2 is a promising candidate barcode for plant species identification.LUO Kun1,2,CHEN ShiLin1,CHEN KeLi2,SONG JingYuan1,YAO Hui1,MA XinYe1,ZHU YingJie3,PANG XiaoHui1,YU Hua1,LI XiWen1,4 & LIU Zhen2 1Institute of Medicinal Plant Development,Peking Union Medical College,Chinese Academy of Medical Sciences,Beijing 100193,China 2College of Pharmacy,Hubei University of Chinese Medicine,Wuhan 430061,China 3School of Bioscience and Engineering,Southwest Jiaotong University,Chengdu 610031,China 4Department of Chemistry,Tsinghua University,Beijing 100084,China 2010Science China(Life Sciences)2010,53,6:32
5Experimental Study of the Pressure Fluctuations in a Pump Turbine at Large Partial Flow Conditions显示文摘Frequent shifts of output and operating mode require a pump turbine with excellent stability. Current researches show that large partial flow conditions in pump mode experience positive-slope phenomena with a large head drop. The pressure fluctuation at the positive slope is crucial to the pump turbine unit safety. The operating instabilities at large partial flow conditions for a pump turbine are analyzed. The hydraulic performance of a model pump turbine is tested with the pressure fluctuations measured at unstable operating points near a positive slope in the performance curve. The hydraulic performance tests show that there are two separated positive-slope regions for the pump turbine, with the flow discharge for the first positive slope from 0.85 to 0.91 times that at the maximum efficiency point. The amplitudes of the pressure fluctuations at these unstable large partial flow conditions near the first positive slope are much larger than those at stable operating condtions. A dominant frequency is measured at 0.2 times the impeller rotational frequency in the flow passage near the impeller exit, which is believed to be induced by the rotating stall in the flow passage of the wicket gates. The test results also show hysteresis with pressure fluctuations when the pump turbine is operated near the first positive slope. The hysteresis creates different pressure fluctuations for those operation points even though their flow rates and heads are similar respectively. The pressure fluctuation characteristics at large partial flow conditions obtained by the present study will be helpful for the safe operation of pumped storage units.RAN Hongjuan LUO Xianwu ZHU Lei ZHANG Yao WANG Xin XU Hongyuan 2012Chinese Journal of Mechanical Engineering2012,25,6:33
6Current Status and Challenge of Pseudorabies Virus Infection in China显示文摘Pseudorabies(PR),also called Aujeszky's disease,is a highly infectious disease caused by pseudorabies virus(PRV).Without specific host tropism,PRV can infect a wide variety of mammals,including pig,sheep,cattle,etc.,thereby causing severe clinical symptoms and acute death.PRV was firstly reported in China in 1950s,while outbreaks of emerging PRV variants have been documented in partial regions since 2011,leading to significant economic losses in swine industry.Although scientists have been devoting to the design of diagnostic approaches and the development of vaccines during the past years,PR remains a vital infectious disease widely prevalent in Chinese pig industry.Especially,its potential threat to human health has also attracted the worldwide attention.In this review,we will provide a summary of current understanding of PRV in China,mainly focusing on PRV history,the existing diagnosis methods,PRV prevalence in pig population and other susceptible mammals,molecular characteristics,and the available vaccines against its infection.Additionally,promising agents including traditional Chinese herbal medicines and novel inhibitors that may be employed to treat this viral infection,are also discussed.Lei Tan Jun Yao Yadi Yang Wei Luo Xiaomin Yuan Lingchen Yang Aibing Wang 2021Virologica Sinica2021,36,4:34
7Risk factors for primary liver carcinoma in Chinese population显示文摘AIM: To evaluate the risk factors for primary liver carcinoma (PLC) in Chinese population.METHODS: Chinese Biomedical Literature Database,China Hospital Knowledge Database and MEDLINE were searched. All the related literatures were screened, and the risk factors for PLC in Chinese population were studied.Heterogeneity was evaluated by odds ratio (OR) q test.Combined OR and its 95% confidence interval (95%CI)were calculated, the association between the investigated risk factors and PLC was determined. Validity and bias of the findings were evaluated by sensitivity analysis and funnel plot analysis respectively.RESULTS: Fifty-five of one hundred and ninety identified studies were accepted according to the inclusive criteria.Ten factors related to PLC were demonstrated by sensitive analysis and funnel plot analysis. They were cirrhosis (OR = 11.97, P= 0.000), HBV infection (OR = 11.34, P= 0.000),HCV infection (OR = 4.28, P = 0.000), family history of liver cancer (OR = 3.49, P = 0.000), unstable emotion (OR = 2.20, P = 0.000), depressed characters (OR = 3.07,P = 0.000), aflatoxin (OR = 1.80, P = 0.000), alcoholic (OR = 1.88, P = 0.000), intake of musty food (OR = 1.87,P = 0.000) and drinking contaminated water from pond (OR = 1.77, P= 0.003).CONCLUSION: The main risk factors for PLC in China are liver diseases, family history of liver carcinoma, poor psychic status, afiatoxin, and some unhealthy behaviors.Rui-Hong Luo Zhi-Xin Zhao Zhi-Liang Gao Ji-Lu Yao Xu-Yu Zhou 2005World Journal of Gastroenterology2005,11,28:26
8Effect of Laser Power on the Cladding Temperature Field and the Heat Affected Zone显示文摘H13 powder is cladded on steel P20(base)by continuous CO2 laser,and the influence of technological parameters such as the laser power is analyzed.The 3-D model of synchronous powder feeding is built under Gauss heat source.The simulative results in the heat affected zone are compared with the experimental ones,and the average errors of width and depth are 15% and 4.5%,respectively.It is found that the simulative results provide basic data for investigating of laser cladding further.LUO Fang YAO Jian hua HU Xia xia CHAI Guo-zhong 2011Journal of Iron and Steel Research(International)2011,18,1:25
9Effects of Adipose-derived Mesenchymal Stem Cell Exosomes on Corneal Stromal Fibroblast Viability and Extracellular Matrix Synthesis显示文摘Ting Shen Qing-Qing Zheng Jiang Shen Qiu-Shi Li Xing-Hui Song Hong-Bo Luo Chao-Yang Hong Ke Yao 2018Chinese Medical Journal2018,,6:23
10A novel gene delivery system targeting cells expressing VEGF receptors显示文摘Two ligand oligopeptides GV1 and GV2 were designed according to the putative binding region of VEGF to its receptors. GV1, GV2 and endosome releasing oligopeptide HA20 were conjugated with poly-L-lysine or protamine and the resulting conjugates could interact with DNA in a noncovalent bond to form a complex. Using pSV2-β-galactosidase as a reporter gene, it has been demonstrated that exogenous gene was transferred into bovine aortic arch-derived endothelial cells (ABAE) andhuman malignant melanoma cell lines (A375) in vitro. In vivo experiments, exogenous gene was transferred into tumor vascular endothelial cells and tumor cells of subcutaneously transplanted human colon cancer LOVO, human malignant melanoma A375 and human hepatoma graft in nude mice. This system could also target gene to intrahepatically transplanted human hepatoma injected via portal vein in nude mice. These results are correlated with theGene delivery system targeting VEGF receptors relevant receptors (flt-1, flk-1/KDR) expression on the targeted cells and tissues.LI JUN MIN JUN SONG HAN YI HUANG PEI KUN TIAN SHU MIN QU MIN YAO HUI QIU JIANG DA FANG WAN JING CHU LUO CHENG XIAO GU JIAN REN GU( National Labomtory for Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai 200032,China)(National Laboratory of 1999Cell Research1999,9,1:22
11Targeted puncture of left branch of intrahepatic portal vein in transjugular intrahepatic portosystemic shunt to reduce hepatic encephalopathy显示文摘BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS) is currently used for the treatment of complications of portal hypertension. The incidence of hepatic encephalopathy(HE) remains a problem in TIPS placement. It has been reported that the right branch mainly receives superior mesenteric venous blood while the left branch mainly receives blood from the splenic vein. We hypothesized that targeted puncture of the left portal vein would divert the non-nutritive blood from the splenic vein into the TIPS shunt; therefore, targeted puncture of the left branch of the intrahepatic portal vein during TIPS may reduce the risk of HE.AIM To evaluate the influence of targeted puncture of left branch of portal vein in TIPS on HE.METHODS A retrospective analysis of 1244 patients with portal-hypertension-related complications of refractory ascites or variceal bleeding who underwent TIPS from January 2000 to January 2013 was performed. Patients were divided into group A(targeting left branch of portal vein, n = 937) and group B(targeting right branch of portal vein, n = 307). TIPS-related HE and clinical outcomes were analyzed.RESULTS The symptoms of ascites and variceal bleeding disappeared within a short time.By the endpoint of follow-up, recurrent bleeding and ascites did not differ significantly between groups A and B(P = 0.278, P = 0.561, respectively).Incidence of HE differed significantly between groups A and B at 1 mo(14.94% vs36.80%, χ~2 = 4.839, P = 0.028), 3 mo(12.48% vs 34.20%, χ~2 = 5.054, P = 0.025), 6 mo(10.03% vs 32.24%, χ~2 = 6.560, P = 0.010), 9 mo(9.17% vs 31.27%, χ~2 = 5.357, P =0.021), and 12 mo(8.21% vs 28.01, χ~2 = 3.848, P = 0.051). There were no significant differences between groups A and B at 3 years(6.61% vs 7.16%, χ~2 = 1.204, P =0.272) and 5 years(5.01% vs 6.18%, χ~2 = 0.072, P = 0.562). The total survival rate did not differ between groups A and B(χ~2 = 0.226, P = 0.634, log-rank test).CONCLUSION Targeted puncture of the left branch of the intrahepatic portal vein during TIPS may reduce the risk of HE but has no direct influence on prognosis of portalhypertension-related complications.Shi-Hua Luo Jian-Guo Chu He Huang Guo-Rui Zhao Ke-Chun Yao 2019World Journal of Gastroenterology2019,25,9:22
12Clinical trial with traditional Chinese medicine intervention ''tonifying the kidney to promote liver regeneration and repair by affecting stem cells and their microenvironment'' for chronic hepatitis B-associated liver failure显示文摘AIM:To study the clinical efficacy of traditional Chinese medicine(TCM)intervention'tonifying the kidney to promote liver regeneration and repair by affecting stem cells and their microenvironment'('TTK')for treating liver failure due to chronic hepatitis B.METHODS:We designed the study as a randomized controlled clinical trial.Registration number of Chinese Clinical Trial Registry is Chi CTR-TRC-12002961.A total of 144 patients with liver failure due to infection with chronic hepatitis B virus were enrolled in this randomized controlled clinical study.Participants were randomly assigned to the following three groups:(1)a modern medicine control group(MMC group,36patients);(2)a'tonifying qi and detoxification'('TQD')group(72 patients);and(3)a'tonifying the kidney to promote liver regeneration and repair by affecting stem cells and their microenvironment'('TTK')group(36patients).Patients in the MMC group received general internal medicine treatment;patients in the'TQD'group were given a TCM formula'tonifying qi and detoxification'and general internal medicine treatment;patients in the'TTK'group were given a TCM formula of'TTK'and general internal medicine treatment.All participants were treated for 8 wk and then followed at 48 wk following their final treatment.The primaryefficacy end point was the patient fatality rate in each group.Measurements of various virological and biochemical indicators served as secondary endpoints.The one-way analysis of variance and the t-test were used to compare patient outcomes in the different treatment groups.RESULTS:At the 48-wk post-treatment time point,the patient fatality rates in the MMC,'TQD',and'TTK'groups were 51.61%,35.38%,and 16.67%,respectively,and the differences between groups were statistically significant(P<0.05).However,there were no significant differences in the levels of hepatitis B virus DNA or prothrombin activity among the three groups(P>0.05).Patients in the'TTK'group had significantly higher levels of serum total bilirubin compared to MMC subjects(339.40μmol/L±270.09μmol/L vs 176.13μmol/L±185.70μmol/L,P=0.014).Serum albumin levels were significantly increased in both the'TQD'group and'TTK'group as compared with the MMC group(31.30 g/L±4.77g/L,30.72 g/L±2.89 g/L vs 28.57 g/L±4.56 g/L,P<0.05).There were no significant differences in levels of alanine transaminase among the three groups(P>0.05).Safety data showed that there was one case of stomachache in the'TQD'group and one case of gastrointestinal side effect in the'TTK'group.CONCLUSION:Treatment with'TTK'improved the survival rates of patients with liver failure due to chronic hepatitis B.Additionally,liver tissue was regenerated and liver function was restored.Han-Min Li Zhi-Hua Ye Jun Zhang Xiang Gao Yan-Ming Chen Xin Yao Jian-Xun Gu Lei Zhan Yang Ji Jian-Liang Xu Ying-He Zeng Fan Yang Lin Xiao Guo-Guang Sheng Wei Xin Qi Long Qing-Jing Zhu Zhao-Hong Shi Lian-Guo Ruan Jia-Yao Yang Chang-Chun Li Hong-Bin Wu Sheng-Duo Chen Xin-La Luo 2014World Journal of Gastroenterology2014,20,48:20
13A Hybrid Forecasting Framework Based on Support Vector Regression with a Modified Genetic Algorithm and a Random Forest for Traffic Flow Prediction显示文摘The ability to perform short-term traffic flow forecasting is a crucial component of intelligent transportation systems. However, accurate and reliable traffic flow forecasting is still a significant issue due to the complexity and variability of real traffic systems. To improve the accuracy of short-term traffic flow forecasting, this paper presents a novel hybrid prediction framework based on Support Vector Regression(SVR) that uses a Random Forest(RF) to select the most informative feature subset and an enhanced Genetic Algorithm(GA) with chaotic characteristics to identify the optimal forecasting model parameters. The framework is evaluated with real-world traffic data collected from eight sensors located near the I-605 interstate highway in California. Results show that the proposed RFCGASVR model achieves better performance than other methods.Lizong Zhang Nawaf R Alharbe Guangchun Luo Zhiyuan Yao Ying Li 2018Tsinghua Science and Technology2018,23,4:19
14Changes in Phosphorus Fractions, pH, and Phosphatase Activity in Rhizosphere of Two Rice Genotypes显示文摘A rhizobox experiment with two phosphorus (P) treatments, zero-P (0 mg P kg-1) and plus-P (100 mg P kg-1) as Ca(H2PO4)2·H2O, was conducted to study the chemical and biochemical properties in the rhizosphere of two rice genotypes (cv. Zhongbu 51 and Pembe) different in P uptake ability and their relationship with the depletion of soil P fractions. Plant P uptake, pH, phosphatase activity, and soil P fractions in the rhizosphere were measured. Both total dry weight and total P uptake of Pembe were significantly (P < 0.05) higher than those of Zhongbu 51 in the zero-P and plus-P treatments. Significant depletions of resin-Pi, NaHCO3-Pi, NaHCO3-Po, and NaOH-Pi, where Pi stands for inorganic P and Po for organic P, were observed in the rhizosphere of both Zhongbu 51 and Pembe under both P treatments. Pembe showed a greater ability than Zhongbu 51 in depleting resin-Pi, NaHCO3-Pi, NaHCO3-Po, NaOH-Pi, and NaOH- Po in the rhizosphere. HCl-Pi and residual-P were not depleted in the rhizosphere of both genotypes, regardless of P treatments despite significant acidification in the rhizosphere of Pembe under zero-P treatment. Higher acid phosphatase (AcPME) activity and alkaline phosphatase (AlPME) activity were observed in the rhizosphere of both Zhongbu 51 and Pembe compared to the corresponding controls without plant. AcPME activity was negatively (P < 0.01) correlated to NaHCO3-Po concentration in the rhizosphere of both Zhongbu 51 and Pembe, suggesting that AcPME was associated with the mineralization of soil organic P.LI Yong-Fu LUO An-Cheng WEI Xing-Hua YAO Xu-Guo 2008Pedosphere2008,18,6:18
15Association between the rate of the morning surge in blood pressure and cardiovascular events and stroke显示文摘LUO Yu WANG Yan-li WU Ying-biao XU Yao Geoffrey A. Head Macgrathy Barry LIANG Yu-lu 2013Chinese Medical Journal2013,,3:18
16Complete chloroplast genome sequence of Magnolia grandiflora and comparative analysis with related species显示文摘Magnolia grandiflora is an important medicinal,ornamental and horticultural plant species.The chloroplast(cp) genome of M.grandiflora was sequenced using a 454 sequencing platform and the genome structure was compared with other related species.The complete cp genome of M.grandiflora was 159623 bp in length and contained a pair of inverted repeats(IR) of 26563 bp separated by large and small single copy(LSC,SSC) regions of 87757 and 18740 bp,respectively.A total of 129 genes were successfully annotated,18 of which included introns.The identity,number and GC content of M.grandiflora cp genes were similar to those of other Magnoliaceae species genomes.Analysis revealed 218 simple sequence repeat(SSR) loci,most composed of A or T,contributing to a bias in base composition.The types and abundances of repeat units in Magnoliaceae species were relatively conserved and these loci will be useful for developing M.grandiflora cp genome vectors.In addition,results indicated that the cp genome size in Magnoliaceae species and the position of the IR border were closely related to the length of the ycf1 gene.Phylogenetic analyses based on 66 shared genes from 30 species using maximum parsimony(MP) and maximum likelihood(ML) methods provided strong support for the phylogenetic position of Magnolia.The availability of the complete cp genome sequence of M.grandiflora provides valuable information for breeding of desirable varieties,cp genetic engineering,developing useful molecular markers and phylogenetic analyses in Magnoliaceae.LI XiWen GAO HuanHuan WANG YiTao SONG JingYuan HENRY Robert WU HeZhen HU ZhiGang YAO Hui LUO HongMei LUO Kun PAN HongLin CHEN ShiLin 2013Science China(Life Sciences)2013,56,2:17
17Insulin Autoimmune Syndrome: 73 Cases of Clinical Analysis显示文摘Autoimmune hypoglycemia,also called insulin autoimmune syndrome (IAS),was first reported by Hirata and Ishizu[1] in 1972 in Japan.IAS[2] is characterized by the diagnostic criteria of spontaneous hypoglycemia without evidence of exogenous insulin administration,high levels of total immunoreactive insulin,and the presence of a high titer of insulin autoantibodies.Yun-Lin Wang Pei-Wei Yao Xiao-Ting Zhang Zhuo-Zhang Luo Pei-Qiang Wu Fang Xiao 2015Chinese Medical Journal2015,,17:17
18NUMERICAL INVESTIGATION OF THE VENTILATED CAVITATING FLOW AROUND AN UNDER-WATER VEHICLE BASED ON A THREE-COMPONENT CAVITATION MODEL显示文摘Based on the Reynolds-Averaged Navier-Stokes equations and mass transfer model,an approach,where a three-component cavitation model is proposed,is presented to simulate ventilated cavitating flow as well as natural cavitation.In the proposed cavitation model,the initial content of nucleus in the local flow field is updated instantaneously,and is coupled with the Rayleigh-Plesset equation to capture the cavity development.The proposed model is applied to simulate the cavitating flow around an under-water vehicle in different cavitation conditions.The results indicate that for the natural and ventilated cavitation simulation,the predicted cavitation characteristics including the cavity length,cavity diameter and cavity shape agree satisfactorily with the analytic and experimental results,for the ventilated cavitation,the proposed methods reproduce the special behavior that the axial line of the cavity bends and rises at the tail part.The study concludes that the ventilated flow rate of the non-condensate gas influences the development of natural cavitation as well as ventilated cavitation,and the vapor cavity is suppressed remarkably by the gas cavity with the increase of the gas ventilation.JI Bin LUO Xian-wu PENG Xiao-xing ZHANG Yao WU Yu-lin XU Hong-yuan 2010Journal of Hydrodynamics2010,22,6:16
19Endoloop ligation after endoscopic mucosal resection using a transparent cap: A novel method to treat small rectal carcinoid tumors显示文摘BACKGROUND Local endoscopic resection is an effective method for the treatment of small rectal carcinoid tumors, but remnant tumor at the margin after resection remains to be an issue.AIM To evaluate the efficacy and safety of resection of small rectal carcinoid tumors by endoloop ligation after cap-endoscopic mucosal resection(LC-EMR) using a transparent cap.METHODS Thirty-four patients with rectal carcinoid tumors of less than 10 mm in diameter were treated by LC-EMR(n = 22) or endoscopic submucosal dissection(ESD)(n =12) between January 2016 and December 2017. Demographic data, complete resection rates, pathologically complete resection rates, operation duration, and postoperative complications were collected. All cases were followed for 6 to 30 mo.RESULTS A total of 22 LC-EMR cases and 12 ESD cases were enrolled. The average age was48.18 ± 12.31 and 46.17 ± 12.57 years old, and the tumor size was 7.23 ± 1.63 mm and 7.50 ± 1.38 mm, respectively, for the LC-EMR and ESD groups. Resection time in the ESD group was longer than that in the LC-EMR group(15.67 ± 2.15 min vs 5.91 ± 0.87 min; P < 0.001). All lesions were completely resected at one time. No perforation or delayed bleeding was observed in either group.Pathologically complete resection(P-CR) rate was 86.36%(19/22) and 91.67%(11/12) in the LC-EMR and ESD groups(P = 0.646), respectively. Two of the three cases with a positive margin in the LC-EMR group received transanal endoscopic microsurgery(TEM) and tumor cells were not identified in the postoperative specimens. The other case with a positive margin chose follow-up without further operation. One case with remnant tumor after ESD received further local ligation treatment. Neither local recurrence nor lymph node metastasis was found during the follow-up period.CONCLUSION LC-EMR appears to be an efficient and simple method for the treatment of small rectal carcinoid tumors, which can effectively avoid margin remnant tumors.Ding-Guo Zhang Su Luo Feng Xiong Zheng-Lei Xu Ying-Xue Li Jun Yao Li-Sheng Wang 2019World Journal of Gastroenterology2019,25,10:15
20Spatial-temporal characteristics of lake area variations in Hoh Xil region from 1970 to 2011显示文摘As one of the areas with numerous lakes on the Tibetan Plateau, the Hoh Xil region plays an extremely important role in the fragile plateau eco-environment. Based on topographic maps in the 1970 s and Landsat TM/ETM+ remote sensing images in the 1990 s and the period from 2000 to 2011, the data of 83 lakes with an area above 10 km2 each were obtained by digitization method and artificial visual interpretation technology, and the causes for lake variations were also analyzed. Some conclusions can be drawn as follows.(1) From the 1970 s to 2011, the lakes in the Hoh Xil region firstly shrank and then expanded. In particular, the area of lakes generally decreased during the 1970s–1990s. Then the lakes expanded from the 1990 s to 2000 and the area was slightly higher than that in the 1970 s. The area of lakes dramatically increased after 2000.(2) From 2000 to 2011, the lakes with different area ranks in the Hoh Xil region showed an overall expansion trend. Meanwhile, some regional differences were also discovered. Most of the lakes expanded and were widely distributed in the northern, central and western parts of the region. Some lakes were merged together or overflowed due to their rapid expansion. A small number of lakes with the trend of area decrease or strong fluctuation were scattered in the central and southern parts of the study area. And their variations were related to their own supply conditions or hydraulic connection with the downstream lakes or rivers.(3) The increase in precipitation was the dominant factor resulting in the expansion of lakes in the Hoh Xil region. The secondary factor was the increase in meltwater from glaciers and frozen soil due to climate warming.YAO Xiaojun LIU Shiyin LI Long SUN Meiping LUO Jing 2014Journal of Geographical Sciences2014,24,4:14
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