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Microbiological assessment of indoor air of a teaching hospital in Nigeria

Asian Pacific Journal of Tropical Biomedicine 2012年第6期2卷 465-468页

作者： Awosika sa Olajubu fa Amusa NA Department of Microbiology Olabisi Onabanjo University Department of Medical Microbiology & Parasitology Olabisi Onabanjo University Teaching Hospital Department of Plant Science & Applied Zoology Olabisi Onabanjo University

Objective:To investigate the quality of indoor air of different wards and units of Olabisi Onabanjo University Teaching Hospital, sagamu, to ascertain their contribution to infection rate in the ***:The microbial quality of indoor air of nine wards/units of Olabisi Onabanjo University Teaching Hospital, sagamu, Nigeria was conducted. Sedimentation technique using open Petri-dishes containing different culture media was employed and samplings were done twice daily, one in the morning shortly after cleaning and before influx of people/patients into the wards/units and the other in the evening when a lot of activities would have taken place in these wards. Isolates were identified according to standard ***:Results showed that there was a statistically significant difference(氈2= 6.0167) in the bacteria population of the different sampling time whereas it was not so for fungi population(氈2= 0.2857). Male medical ward(MMW) and male surgical general(MSG) recorded the highest bacterial and fungal growth while the operating theatre(OT) was almost free of microbial burden. The bacteria isolates were Staphylococcus aureus, Klebsiellasp., Bacillus cereus, Bacillus subtilis, Streptococcus pyogenes andSerratia marscenceswhile the fungi isolates includedAspergillus flavus, Penicilliumsp.,Fusariumsp.,Candida *** aureuswas the predominantly isolated bacterium whilePenicilliumsp. was the most isolated ***:Though most of the microbial isolates were potential and or opportunistic pathogens, there was no correlation between the isolates in this study and the surveillance report of nosocomial infection during the period of study, hence the contribution of the indoor air cannot be established. From the reduction noticed in the morning samples, stringent measures such as proper disinfection and regular cleaning, restriction of patient relatives' movement in and out of the wards/units need to be enforced so as to imp

关键词： Indoor air OOUTH Open-plate technique Nosocomial infections Staphylococcus aureus Microbiological assessment Microbial quality Bacterial isolate Fungal isolate Opportunistic pathogen Nosocomial infection Infection rate Microbial isolate Penicilliumsp Sedimentation technique

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Numerical Simulation of Macrosegregation Caused by Thermal–Solutal Convection and Solidification Shrinkage Using ALE Model

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Acta Metallurgica Sinica(English Letters) 2019年第11期32卷 1396-1406页

作者： Kang-Xin Chen Hou-fa Shen Key Laboratory for Advanced Materials Processing Technology Ministry of Education School of Materials Science and Engineering Tsinghua University

Solidifi cation shrinkage has been recognized as an important factor for macrosegregation formation. An arbitrary Lagrangian–Eulerian(ALE) model is constructed to predict the macrosegregation caused by thermal–solutal convection and solidi-fi cation shrinkage. A novel mesh update algorithm is developed to account for the domain change induced by solidifi cation shrinkage. The velocity–pressure coupling between the non-homogenous mass conservation equation and momentum equation is addressed by a modifi ed pressure correction method. The governing equations are solved by the streamline-upwind/Petrov–Galerkin-stabilized fi nite element algorithm. The application of the model to the Pb-19.2 wt%Sn alloy solidifi cation problem is considered. The inverse segregation is successfully predicted, and reasonable agreement with the literature results is obtained. Thus, the ALE model is established to be a highly effective tool for predicting the macrosegregation caused by solidifi cation shrinkage and thermal–solutal convection. Finally, the effect of solidifi cation shrinkage is analyzed. The results demonstrate that solidifi cation shrinkage delays the advance of the solidifi cation front and intensifi es the segregation.

关键词： Macrosegregation Solidification shrinkage Finite element method Arbitrary Lagrangian–Eulerian(ALE)

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IBEA-SVM: An Indicator-based Evolutionary Algorithm Based on Pre-selection with Classification Guided by SVM

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 1-26页

作者： LI Hao-ran HE fa-zhi YAN Xiao-hu School of Computer Science and Technology Wuhan University State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University

Multi-objective optimization has many important applications and becomes a challenging issue in applied science. In typical multi-objective optimization algorithms, such as Indicator-based Evolutionary Algorithm(IBEA), all of parents and offspring need to be evaluated in every generation, and then the better solutions of them are selected as the next generation candidates. This leads to a large amount of calculation and slows down convergence rate for IBEA related applications. Our discovery is that the evaluation of evolutionary algorithm is a binary classi?cation in nature and a meaningful preselection method will accelerate the convergence rate. Therefore this paper presents a novel preselection approach to improve the performance of the IBEA, in which a SVM(Support Vector Machine) classi?er is adopted to sort the promising solutions from unpromising solutions and then the newly generated solutions are conversely added as train sample to increase the accuracy of the classi?er. Firstly, we proposed an online and asynchronous training method for SVM model with empirical kernel. The initial population is randomly generated among population size, which is used as initial training. In the process of training, SVM classi?er is modi?ed and perfected to adapt to the evolutionary algorithm sample. Secondly, the classi?er divides all the new generated solutions from the whole solution spaces into promising solutions and unpromising ones. And only the promising ones are forwarded for evaluation. In this way, the evaluation time can be greatly reduced and the solution quality can be obviously improved. Thirdly, the promising and unpromising solutions are labeled as new train samples in next generation to re?ne classi?er model. A number of experiments on benchmark functions validates the proposed approach. The results show that IBEA-SVM can signi?cantly outperform previous works.

关键词： multi-objective optimization SVM IBEA training classification

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Snake Model for the Extraction of Loess Shoulder-line from DEMs

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Journal of Mountain Science 2014年第6期11卷 1552-1559页

作者： YAN Shi-jiang TANG Guo'an LI fa-yuan ZHANG Lei Key laboratory of Virtual Geographic Environment Ministry of education Nanjing Normal University School of Resource and Environmental Engineering Anhui University

Shoulder lines are the most important landform demarcations for geographical analysis,soil erosion modeling and land use planning in the Loess Plateau area of *** paper proposes an automatic,effective and accurate method of determining loess shoulder line from DEMs by integrating a hydrological D8 algorithm and a snake *** watershed boundary line is adopted as the initial contour which evolves to identify the exact position of loess shoulder-line by the guidance of an external force of snake model from *** show that the method overcomes the difficulties in both threshold selection for edge detection and the disconnecting issues in former extraction *** accuracy evaluation of shoulder-line maps from the two test sites of the loess plateau area show obvious improvements in the *** average contour matching distance of the new method is 12.0 m on 5 m resolution DEM,and shows improvement in the accuracy and *** comparisons of accuracy evaluations of the two test sites show that the snake model method performs better in the loess plain area than in the area with high gully density.

关键词： Snake model DEM loess shoulder-line

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Generation and evolution of multiple operation states in passively mode-locked thulium-doped fiber laser by using a graphene-covered-microfiber

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Chinese Physics B 2018年第8期27卷 301-307页

作者： Xiao-fa Wang Jun-Hong Zhang Xlao-Llng Peng Xue-Feng Mao College of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsKey Laboratory of Optica/Fiber Communication TechnologyChongqing Education CommissionChongqing 400065China

Using graphene-covered-microfiber （GCM） as a saturable absorber, the generation and evolution of multiple operation states are proposed and demonstrated in passively mode-locked thulium-doped fiber laser. The microfiber was fabricated using the flame brushing method to an interaction length of - 1.2 cm with a waist diameter of -10 μm. Graphene layers were grown on copper foils by chemical vapor deposition and transferred onto the polydimethylsiloxane （PDMS） to form a PDMS/graphene film, which allowed light-graphene interaction via evanescent field. With the increase of the pump power from 1.25 W to 2.15 W, five different lasing regimes, including continuous-wave, conventional soliton mode-locking, multi- soliton mode-locking, a period of transition, and noise-like mode-locking, were achieved in a fiber ring cavity. To the best of our knowledge, it is the first report of the generation and evolution of multiple operation states by covering graphene on the microfiber in the 2-μ.m region. The results demonstrate that GCM can be a promising method for fabricating all fiber sa, and the switchable operation states can provide more portability in complex application domain.

关键词： fiber lasers mode-locked, thulium-doped fiber graphene microfiber

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海面远距离目标运动属性判别方法

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电光与控制 2014年第1期21卷 15-17,90页

作者：杨士英花良发马飒飒空军预警学院黄陂士官学校武汉430345 军械工程学院军械技术研究所石家庄050003

基于临近空间平台的T1R1系统,以对海面远距离目标运动属性的快速判别为需求,提出了对目标运动属性的快速判别方法。该方法不用计算目标位置,仅需根据单侦察时差参数观测值的统计特征来判别目标的运动属性。仿真结果验证了该方法的有效性。

关键词：海面远距离目标运动属性时差临近空间平台

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Expression of NF-kappaB in rotavirus-induced damage to the liver and biliary tract in neonatal mice

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Hepatobiliary & Pancreatic Diseases International 2007年第2期6卷 188-193页

作者： Huang, Lei Gu, Wei-Zhong Si, Xin-Min Wei, Ming-fa Feng, Jie-Xiong Huazhong Univ Sci & Technol Dept Pediat Surg Tongji Hosp Wuhan 430030 Peoples R China Zhejiang Univ Sch Med Dept Pathol Childrens Hosp Hangzhou 310003 Peoples R China Wuhan Univ Renmin Hosp Dept Gastroenterol Wuhan 430060 Peoples R China

BACKGROUND: Biliary atresia, the etiology of which still remains unclear, occurs exclusively in newborns and most are infected with rotavirus. In this study, we aimed to investigate the histopathological patterns of different kinds of rotavirus in the liver and biliary tract of neonatal mice and the expression of NF-kappa B in the liver and biliary tract of infected mice. METHODS: Twenty-three adult mice (8 were male and 15 female) were divided into 8 breeding pairs, and each pair (I male and 2 females) was housed in a cage in a laminar flow hood. Newborn mice, 24-48 hours old were randomly divided into A, B and C groups. The A and B groups were respectively inoculated with MMU18006 and sa11 rotavirus through the intraperitoneal route, while group C as blank control was only inoculated with culture medium. The liver was dissected after 5, 10, 15, 21 and 28 days; the weight of each mouse and the histopathological patterns in the liver were recorded. The expression of NF-kappa B in the liver and intrahepatic bile ducts was detected by immunohistochemical staining and the expression intensity was analyzed with a GT-2 imaging instrument. RESULTS: The average increase in weight of infected mice was significantly slower than that of the normal control, while the growth rate of group A (injected with MMU18006 rotavirus) was slower than that of group B (sa11 rotavirus). In infected mice, the acute and chronic inflammation of liver and intra- and extra-hepatic bile ducts was more significant in group A. Stenosis was found in most intrahepatic bile ducts, and sporadically in extrahepatic bile ducts. The expression of NF-kappa B in infected mice was dramatically higher than that of the normal control, while the expression in group A was higher than in group B. CONCLUSIONS: Significant damage to the liver and biliary tract of neonatal mice can be induced by inoculating MMU18006 rotavirus through the intraperitoneal route, which is very similar to the pathology of biliary atresi

关键词： rotavirus biliary atresia NF-kappa B

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Y–Z deformable magnetic ring for the treatment of rectal stricture: A case report and review of literature

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World Journal of Gastroenterology 2024年第6期30卷 599-606页

作者： Miao-Miao Zhang Huan-Chen Sha Yuan-fa Qin Yi Lyu Xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

BACKGROUND Treatment of postoperative anastomotic stenosis for colorectal cancer is often challenging,especially for patients who do not respond well to *** cases where patients have undergone an enterostomy,the stenosis can be easily resolved through magnetic ***,common magnetic compre-ssion techniques cannot be performed on those without *** design-ed a novel Y–Z deformable magnetic ring(Y–Z DMR)and successfully applied it to a patient with a stenosis rectal anastomosis and without enterostomy after rectal cancer *** SUMMARY We here report the case of a 57-year-old woman who had undergone a laparo-scopic radical rectum resection(Dixon)for rectal ***,she started fa.ing difficulty in defecation 6 months after *** colonoscopy indicated stenosis of the rectal *** balloon dilation was performed six times on ***,the stenosis still showed a trend of gradual *** the patient did not undergo an enterostomy,the conventional endoscopic magnetic compression technique could not be ***,we imple-mented a Y–Z DMR implemented through the anus under single *** magnetic ring fell off nine days after the operation and the rectal stenosis was *** patient was followed up for six months and reported good *** The Y–Z DMR deformable magnetic ring is an excellent treatment strategy for patients with rectal stenosis and without enterostomy.

关键词： Anastomotic stenosis Colorectal cancer Magnetosurgery Magnetic compression technique Magnetic surgery clinic Case report

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Controlled Synthesis of Dendritic Polyaniline Fibers with Diameters from Nanosize to Submicrometersize

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Chinese Chemical Letters 2005年第11期16卷 1523-1526页

作者： Xiao Cong WANG Shu Jiang DING Jing CAO fa Lun WU Chen ZHOU Zhen Zhong YANG College of Science Tianjin University of Science and Technology Tianjin 300022 State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080

Dendritic polyaniline nanofibers and submicrometer-sized fibers have been synthesized by chemical oxidative polymerization of aniline （An） doped with salicylic acid （sa）. The diameters of the fibers could be controlled easily from 30 to 400 nm by varying the concentration of aniline and salicylic acid at room temperature. Scanning electron microscopy （SEM） and typical transmission electron microscopy （TEM） were applied to investigate their morphologies. . Fourier transform infrared （FTIR） spectrum indicated that the state of the dendritic polyaniline fibers is emerialdine rather than solely the leucoemeraldine or permigraniline forms. The dendritic polyaniline fibers have potential applications as chemical sensors or actuators and neuron devices.

关键词： Dendritic polyaniline synthesis nanofiber.

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Herbivore-induced rice resistance against rice blast mediated by salicylic acid

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Insect Science 2020年第1期27卷 49-57页

作者： Kai-Li Zhang Qing-Song Liu Hou-Xiang Kang Xiao-Mei Liu Xiu-Ping Chen Yu-fa Peng Yun-He Li College of Environment and Plant Protection Hainan UniversityHaikouChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina College of Life Sciences Xinyang Normal UniversityXinyangHenanChina

In agro-ecosystems,plants are important mediators of interactions between their associated herbivorous insects and microbes,and any change in plants induced by one species may lead to cascading effects on interactions with other ***,such effects are regulated by phytohormones such as jasmonic acid(JA)and salicylic acid(sa).Here,we investigated the tripartite interactions among rice plants,three insect herbivores(Chilo suppressalis,Cnaphalocrocis medinalis or Nilapai-vata lugens),and the causal agent of rice blast disease,the fungus Magnaporthe *** found that pre-infestation of rice by *** or *** but not by *** conferred resistance to *** *** and ***,insect infestation without fungal inoculation induced the accumulation of both JA and sa in rice *** contrast,infestation by *** increased JA levels but reduced sa *** exogenous application of sa but not of JA conferred resistance against *** results suggest that preinfestation by C suppressalis or *** conferred resistance against *** by increasing sa *** findings enhance our understanding of the interactions among rice plant,insects and pathogens,and provide valuable information for developing an ecologically sound strategy for controlling rice blast.

关键词： induced defense jasmonic acid plant-insect-pathogen interaction rice salicylic acid

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