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An Outbreak of Infections Caused by a Klebsiella pneumoniae ST11 Clone Coproducing Klebsiella pneumoniae Carbapenemase-2 and RmtB in a Chinese Teaching Hospital

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Chinese Medical Journal 2016年第17期129卷 2033-2039页

作者： Jun Li Ming-Xiang Zou Hai-Chen Wang qing-ya dou Yong-Mei Hu Qun yan Wen-En Liu Department of Clinicat Laboratory Xiangya Hospital Central South University Changsha Hunan 410008 China Department of Infection Control Center Xiangya Hospital Central South University Changsha Hunan 410008 China

Background： Klebsiellapneumoniae carbapenemase （KPC）-producing K. pneumoniae bacteria, which cause serious disease outbreaks worldwide, was rarely detected in Xiangya Hospital, prior to an outbreak that occurred from August 4, 2014, to March 17, 2015. The aim of this study was to analyze the epidemiology and molecular characteristics of the K. pneumoniae strains isolated during the outbreak. Methods： Nonduplicate carbapenem-resistant K. pneumoniae isolates were screened for blanc,＂ and multiple other resistance determinants using polymerase chain reaction. Subsequent studies included pulsed-field gel electrophoresis （PFGE）, multilocus sequence typing, analysis of plasmids, and genetic organization ofblaKPC-2 locus. Results： Seventeen blaKPC-2-positive K. pneumoniae were identified. A wide range of resistant determinants was detected. Most isolates （88.2%） coharbored blaKPC-2 and rmtB in addition to other resistance genes, including biaSHV-1, blaTEM-1, and aac（3）-lla. The blaKPC-2 and rmtB genes were located on the conjugative IncFIB-type plasmid. Genetic organization of blaKPC-2 locus in most strains was consistent with that of the plasmid pKP048. Four types （A l, A2, A3, and B） were detected by PFGE, and Type A1, an ST11, was the predominant PFGE type. A novel K. pneumoniae sequence type （ST1883） related to STI 1 was discovered. Conclusions： These isolates in our study appeared to be clonal and STI 1 K. pneumoniae was the predominant clone attributed to the outbreak. Coharbing of blaKPC-2 and rmtB, which were located on a transferable plasmid, in clinical K. pneumoniae isolates may lead to the emergence of a new pattern of drug resistance.

关键词： Carbapenem: Klebsiella pneumoniae: Klebsiella pneumoniae Carbapenemase Outbreak: RmtB

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A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi Yun-Hao Xu Ming-Hui Chen Peng Zhao Wen-Bo Deng Ji Xiong Kai Guo ya-qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

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Automatic pattern acquisition from game records in GO

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 100-105页

作者： LIU Zhi-qing dou qing School of Software Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Computer programs of GO are typically constructed using a knowledge-based approach with heuristics and pattern matching because of enormous complexities of the game. In this approach, quantity, quality, and consistency of patterns used in computer programs of GO to a large extent determine the strengths of the programs. This study presents an effective method to acquire automatically comprehensive GO patterns from large collections of game records. Statistical usages of the patterns ensure consistency and quality of the patterns, which in turn can help improve the strengths of computer GO programs. Additionally, statistical usages of patterns from different sources of game records clearly show subtle and significant discrepancies among various types of GO players, and clarify certain myths in the playing of GO.

关键词： computer games automatic knowledge acquisition,spatial patterns recognition

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Simulation and Instability Investigation of the Flow around a Cylinder between Two Parallel Walls

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Journal of Thermal Science 2015年第2期24卷 140-148页

作者： dou Hua-Shu BEN An-qing Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech University

The two-dimensional flows around a cylinder between two parallel walls at Re=40 and Re=100 are simulated with computational fluid dynamics(CFD). The governing equations are Navier-Stokes equations. They are discretized with finite volume method(FVM) and the solution is iterated with PISO Algorithm. Then, the calculating results are compared with the numerical results in literature, and good agreements are obtained. After that, the mechanism of the formation of Karman vortex street is investigated and the instability of the entire flow field is analyzed with the energy gradient theory. It is found that the two eddies attached at the rear of the cylinder have no effect on the flow instability for steady flow, i.e., they don't contribute to the formation of Karman vortex street. The formation of Karman vortex street originates from the combinations of the interaction of two shear layers at two lateral sides of the cylinder and the absolute instability in the cylinder wake. For the flow with Karman vortex street, the initial instability occurs at the region in a vortex downstream of the wake and the center of a vortex firstly loses its stability in a vortex. For pressure driven flow, it is confirmed that the inflection point on the time-averaged velocity profile leads to the instability. It is concluded that the energy gradient theory is potentially applicable to study the flow stability and to reveal the mechanism of turbulent transition.

关键词： numerical simulation cylinder energy gradient theory stability inflection point

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Drift perturbation of subordinate Brownian motions with Gaussian component

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Science China Mathematics 2016年第2期59卷 239-260页

作者： CHEN Zhen-qing dou XiaoMan Department of Mathematics University of Washington Department of Mathematical Sciences Tsinghua University

Let d ≥ 1 and Z be a subordinate Brownian motion on R^d with infinitesimal generator ? + ψ(?),where ψ is the Laplace exponent of a one-dimensional non-decreasing L′evy process(called subordinator). We establish the existence and uniqueness of fundamental solution(also called heat kernel) pb(t, x, y) for non-local operator L^b= ? + ψ(?) + b ?, where Rb is an Rd-valued function in Kato class K_(d,1). We show that p^b(t, x, y)is jointly continuous and derive its sharp two-sided estimates. The kernel pb(t, x, y) determines a conservative Feller process X. We further show that the law of X is the unique solution of the martingale problem for(L^b, C_c~∞(R^d)) and X is a weak solution of Xt = X0+ Zt + integral from n=0 to t(b(Xs)ds, t ≥ 0).Moreover, we prove that the above stochastic differential equation has a unique weak solution.

关键词： subordinate Brownian motion heat kernel Kato class gradient perturbation Feller process L^vysystem martingale problem stochastic differential equation

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On 1-rate and 2-rate multicast 3-stage Clos networks

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 151-156页

作者： dou Wen-qing yaO En-yu Dept. of Math. Shanghai Second Polytechnic Univ. Shanghai 201209 China Dept. of Math. Zhejiang Univ. Zhejiang 310027 China

The 3-stage Clos network C（n, m, r） is considered as the most basic and popular multistage interconnection network which has been widely employed for data communications and parallel computing systems. Quite a lot of efforts has been put on the research of the 3- stage Clos network. Unfortunately, very little is known for the multirate multicast Clos network which is the most complicated case. Firstly a sufficient condition for 1-rate multicast networks to be SNB is given, from which a result for 2-rate multicast networks to be WSNB can easily be gotten. Furthermore, by using a reservation-scheme routing, more specific result for 2-rate multicast networks to be WSNB can be obtained for the case of one of them exceeding 1/2.

关键词： 3-stage Clos network multirate multicast network strictly nonblocking wide-sense nonblocking

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Monkeypox virus:past and present

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World Journal of Pediatrics 2023年第3期19卷 224-230页

作者： ya-Mei dou Hang Yuan Hou-Wen Tian NHC Key Laboratory of Medical Virology and Viral Disease Chinese Center for Disease Control and PreventionNational Institute for Viral Disease Control and Prevention155 Changbai RoadChangPing DistrictBeijing 102206China

Background The objective of this paper is to analyze the current status of monkeypox *** the face of this public health threat,our purpose is to elucidate the clinical characteristics and epidemiology of monkeypox,the developmental progress of monkeypox-related drugs and the vaccines *** sources The literature review was performed in databases including PubMed,Science Direct and Google Scholar up to July *** Since May 2022,the World Health Organization has reported more than 45,000 confirmed cases from 92 nonendemic countries,including nine *** some women and children have been infected so far,most cases have occurred among men who have sex with other men,especially those with multiple sexual partners or anonymous *** Pediatric monkeypox infection has been associated with a higher likelihood of severe illness and mortality than in *** monkeypox illness in pediatrics often requires adjunctive antiviral *** is crucial for all countries to establish sound monitoring and testing systems and be prepared with emergency preparedness.

关键词： Monkeypox Orthopoxvirus Smallpox Zoonotic

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基于CNN和Transformer交叉教学的半监督医学图像分割

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陕西科技大学学报 2025年第1期43卷 185-192页

作者：杨云胡雯青杨虹吴亚男陕西科技大学电子信息与人工智能学院陕西西安710021 西安富德医疗电子有限公司陕西西安710075 西安计量技术研究院陕西西安710199

由于医学图像分割领域缺乏高质量的标注数据,半监督学习方法在医学图像语义分割任务中受到高度重视.为了充分利用卷积神经网络(Convolutional Neural Network,CNN)和Transformer在半监督学习中的优势,本文提出一种基于CNN与Transformer... 详细信息

由于医学图像分割领域缺乏高质量的标注数据,半监督学习方法在医学图像语义分割任务中受到高度重视.为了充分利用卷积神经网络(Convolutional Neural Network,CNN)和Transformer在半监督学习中的优势,本文提出一种基于CNN与Transformer交叉教学的半监督医学图像分割方法.该方法将经典的深度协同训练从一致性正则化简化为交叉教学,利用循环伪标签方案使两个网络的预测差异转换为无监督损失,以鼓励两个网络具有一致的低熵预测.所提方法在ISIC 2018数据集上进行实验,在采用20%的标注比例时,Dice系数和Jaccard系数分别达到87.25%和79.17%,相比于监督U-Net++的训练结果分别提升了2.89%和3.53%,并且优于目前主流的半监督学习方法,验证了所提方法在半监督医学图像分割上的有效性和泛化性.

关键词：半监督学习图像语义分割交叉教学循环伪标签

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A mathematical model of cortical bone remodeling at cellular level under mechanical stimulus

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Acta Mechanica Sinica 2012年第6期28卷 1678-1692页

作者： qing-Hua Qin ya-Nan Wang Research School of Engineering The Australian National University

A bone cell population dynamics model for cor- tical bone remodeling under mechanical stimulus is devel- oped in this paper. The external experiments extracted from the literature which have not been used in the creation of the model are used to test the validity of the model. Not only can the model compare reasonably well with these ex- perimental results such as the increase percentage of final values of bone mineral content （BMC） and bone fracture en- ergy （BFE） among different loading schemes （which proves the validity of the model）, but also predict the realtime devel- opment pattern of BMC and BFE, as well as the dynamics of osteoblasts （OBA）, osteoclasts （OCA）, nitric oxide （NO） and prostaglandin E2 （PGE2） for each loading scheme, which can hardly be monitored through experiment. In conclusion, the model is the first of its kind that is able to provide an in- sight into the quantitative mechanism of bone remodeling at cellular level by which bone cells are activated by mechan- ical stimulus in order to start resorption/formation of bone mass. More importantly, this model has laid a solid foun- dation based on which future work such as systemic control theory analysis of bone remodeling under mechanical stimu- lus can be investigated. The to-be identified control mecha- nism will help to develop effective drugs and combined non- pharmacological therapies to combat bone loss pathologies. Also this deeper understanding of how mechanical forces quantitatively interact with skeletal tissue is essential for the generation of bone tissue for tissue replacement purposes in tissue engineering.

关键词： Cortical bone remodeling Cell population dy-namics Mechanotransduction Mechanosensitivity Bonefracture energy - Bone mineral content

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Mechanism Study on Char Formation of Zinc Acetylacetonate on ABS Resin

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Chinese Journal of Polymer Science 2015年第5期33卷 772-782页

作者： ya-qing Ma 庞永艳 Polymers and Composites Division Ningbo Institute of Materials Technology & EngineeringChinese Academy of Sciences

The mechanism of char formation effect of zinc acetylacetonate（Zn（acac）2） on acrylonitrile-butadiene-styrene copolymer（ABS） was studied. Thermal gravimetric analysis（TGA） was used to study the mass loss and char yield of ABS composites. In situ temperature-dependent Fourier transform infrared spectroscopy（FTIR） was used to characterize the chemical change during thermal decomposition. Roman spectroscopy and scanning electron microscopy（SEM） were applied to characterize the structure and morphology of the char after combustion. Results showed that the presence of Zn（acac）2 not only slowed down thermal decomposition of the ABS composites, but also increased the charred residue. A more compact and denser char layer with higher graphitization degree was formed for ABS composites with Zn（acac）2. To study the char formation mechanism of Zn（acac）2 on ABS, thermal decomposition was analyzed for the composites of Zn（acac）2 with PB, PS and SAN, respectively. Also, the chemical structure change was investigated for Zn（acac）2 during thermal decomposition. Based on these results, it was deduced that the increase of char yield of ABS composites was probably attributed to the interaction between the units of acrylonitrile in ABS and zinc acetate, produced during the thermal decomposition of Zn（acac）2. A proposed mechanism for crosslinking and the subsequent char formation was presented.

关键词： Char formation ABS Zinc acetylacetonate Mechanism Decomposition

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