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Changes in neurological and pathological outcomes in a modified rat spinal cord injury model with closed canal

Neural Regeneration Research 2020年第4期15卷 697-704页

作者： Xin Sun Xing-Zhen Liu Jia Wang Hai-Rong Tao Tong Zhu Wen-Jie Jin Kang-Ping Shen Shanghai Key Laboratory of Orthopedic Implants Department of Orthopedic SurgeryShanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Pathology Shanghai Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

Most animal spinal cord injury models involve a laminectomy,such as the weight drop model or the transection model.However,in clinical practice,many patients undergo spinal cord injury while maintaining a relatively complete spinal canal.Thus,open spinal cord injury models often do not simulate real injuries,and few previous studies have investigated whether having a closed spinal canal after a primary spinal cord injury may influence secondary processes.Therefore,we aimed to assess the differences in neurological dysfunction and pathological changes between rat spinal cord injury models with closed and open spinal canals.Sprague-Dawley rats were randomly divided into three groups.In the sham group,the tunnel was expanded only,without inserting a screw into the spinal canal.In the spinal cord injury with open canal group,a screw was inserted into the spinal canal to cause spinal cord injury for 5 minutes,and then the screw was pulled out,leaving a hole in the vertebral plate.In the spinal cord injury with closed canal group,after inserting a screw into the spinal canal for 5 minutes,the screw was pulled out by approximately 1.5 mm and the flat end of the screw remained in the hole in the vertebral plate so that the spinal canal remained closed;this group was the modified model,which used a screw both to compress the spinal cord and to seal the spinal canal.At 7 days post-operation,the Basso-Beattie-Bresnahan scale was used to measure changes in neurological outcomes.Hematoxylin-eosin staining was used to assess histopathology.To evaluate the degree of local secondary hypoxia,immunohistochemical staining and western blot assays were applied to detect the expression of hypoxia-inducible factor 1α(HIF-1α)and vascular endothelial growth factor(VEGF).Compared with the spinal cord injury with open canal group,in the closed canal group the Basso-Beattie-Bresnahan scores were lower,cell morphology was more irregular,the percentage of morphologically normal neurons was lower,the percentages of HIF-1α-and VEGF-immunoreacti

关键词： Basso-Beattie-Bresnahan scores closed spinal canal HIF-1α hypoxia model nerve regeneration open spinal canal rat secondary injury spinal cord injury VEGF

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Comparative analysis of the effects of gunpowder and plasma ignition in closed vessel tests

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Defence Technology（防务技术） 2019年第5期15卷 668-673页

作者： Radoslaw Trebinski Zbigniew Leciejewski Zbigniew Surma Jakub Michalski Military University of Technology Department of Mechatronics and Aerospace

This paper presents the results of a comparative investigation into the effects of the ignition method on the ballistic properties of a single-base gun propellant,as determined via closed vessel tests.Conventional gunpowder ignition and plasma jet ignition methods were used,and differences in the ignition time were analysed.The influence of the ignition method on the dynamic vivacity is discussed.It is shown that this influence is significant in the first phase of the combustion process,and with respect to the low values of the loading density.In the second phase of the combustion process,and for large values of the loading density,the dynamic vivacity plots for the two ignition methods converge.Regarding the burning law,close values of the exponent were obtained for the two ignition methods.The dynamic vivacity plots determined for plasma ignition reveal stronger dependence on the loading density than those determined for gunpowder ignition.The conclusion is that plasma ignition is not a solution to the problems inherent to the process of determining the ballistic properties of propellants,which results in deviation of the burning process from the geometric burning law.

关键词： closed vessel test Gun propellant Gunpowder ignition Plasma ignition

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Enhancement effect of cumulative second-harmonic generation by closed propagation feature of circumferential guided waves

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Chinese Physics B 2020年第2期29卷 301-308页

作者：高广健邓明晰胡宁项延训 Department of Physics Army Logistics UniversityChongqing 401331China College of Aerospace Engineering Chongqing UniversityChongqing 400044China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

On the basis of second-order perturbation approximate and modal expansion approach,we investigate the enhancement effect of cumulative second-harmonic generation(SHG)of circumferential guided waves(CGWs)in a circular tube,which is inherently induced by the closed propagation feature of CGWs.An appropriate mode pair of primary-and double-frequency CGWs satisfying the phase velocity matching and nonzero energy flux is selected to ensure that the second harmonic generated by primary CGW propagation can accumulate along the circumference.Using a coherent superposition of multi-waves,a model of unidirectional CGW propagation is established for analyzing the enhancement effect of cumulative SHG of primary CGW mode selected.The theoretical analyses and numerical simulations performed directly demonstrate that the second harmonic generated does have a cumulative effect along the circumferential direction and the closed propagation feature of CGWs does enhance the magnitude of cumulative second harmonic generated.Potential applications of the enhancement effect of cumulative SHG of CGWs are considered and discussed.The theoretical analysis and numerical simulation perspective presented here yield an insight previously unavailable into the physical mechanism of the enhancement effect of cumulative SHG by closed propagation feature of CGWs in a circular tube.

关键词： circumferential guided wave second-harmonic generation(SHG) enhancement effect of cumulative SHG closed propagation feature

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On the Cegrell Classes Associated to a Positive closed Current

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Chinese Annals of Mathematics,Series B 2019年第4期40卷 567-584页

作者： Mohamed ZAWAY Department of Mathematics Faculty of Sciences Ad DwadimiShaqra University Department of Mathematics Faculty of Science of Gabes University of Gabes

The aim of this paper is to study the operatoron■ on some classes of plurisubharmonic (psh) functions, which are not necessary bounded, where T is a positive closed current of bidimension (q, q) on an open set ? of C^n. The author introduces two classes F_p^T (?) and■ and shows first that they belong to the domain of definition of the operator■. Then the author proves that all functions that belong to these classes are C_T-quasi-continuous and that the comparison principle is valid for them.

关键词： Positive closed current Plurisubharmonic function Capacity Monge-Ampère Operator

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Weakly closed Graphs and F-Purity of Binomial Edge Ideals

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Algebra Colloquium 2018年第4期25卷 567-578页

作者： Kazunori Matsuda Kitami Institute of Technology Kitami

Herzog,Hibi,Hreinddttir et al.introduced the class of closed graphs,and they proved that the binomial edge ideal JG of a graph G has quadratic GrSbner bases if G is closed.In this paper,we introduce the class of weakly closed graphs as a generalization of the closed graph,and we prove that the quotient ring S/JG of the polynomial ring S=K[x1,...,xn,y1,...,yn]with K a field and n=|V(G)|is F-pure if G is weakly closed.This fact is a generalization of Ohtani's theorem.

关键词： binomial edge ideal closed graph weakly closed graph F-pure

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Novel therapeutic approaches for hepatitis B virus covalently closed circular DNA

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World Journal of Gastroenterology 2015年第23期21卷 7084-7088页

作者： Motoko Ohno Motoyuki Otsuka Takahiro Kishikawa Takeshi Yoshikawa Akemi Takata Kazuhiko Koike Department of Gastroenterology Graduate School of Medicine the University of Tokyo

Hepatitis B virus(HBV) infection is a major global health problem. Although current therapies, such as the use of nucleos(t)ide analogs, inhibit HBV replication efficiently, they do not eliminate covalently closed circular DNA(ccc DNA), which persists in hepatocyte nuclei. As HBV ccc DNA is a viral transcription template, novel therapeutic approaches to directly target HBV ccc DNA are necessary to completely eradicate persistent HBV infections. HBV ccc DNA levels in HBV-infected human liver cells are extremely low; thus, more reliable and simple measurement methods are needed to correctly monitor their levels during therapeutic treatment. Although reverse transcription-polymerase chain reaction or Southern blot procedures are currently used in research studies, these methods are not completely reliable and are also time-consuming and labor-intensive. Genome editing technologies, such as zinc finger nucleases, transcription activator-like effector nucleases, and the clustered regularly interspaced short palindromic repeats/Cas9(CRISPR/Cas9) system, which are designed to target specific DNA sequences, represent highly promising potential therapeutic tools. In particular, the CRISPR/Cas9 system is an easily customizable sequencespecific nuclease with high flexibility and may be the most feasible approach to target HBV ccc DNA. Further research to develop easier, safer, and more effective protocols should be pursued.

关键词： Hepatitis B virus Covalently closed circularHBV DNA Genome editing

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Experimental Study on Performance of a closed Wet Cooling Tower for Air Wet-Bulb Temperature near 0°C

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Journal of Thermal Science 2019年第5期28卷 1015-1023页

作者： ZHOU Yasu ZHANG Pan ZHAO Jingde YANG Honghai BAI Yufeng College of Environmental Science and Engineering Donghua University

closed wet cooling towers(CWCTs) are used widely because of their better water quality and smaller water consumption. However, the operating parameters shown in the technical documents are only for rated conditions in summer, not for any other conditions, especially in low air wet-bulb temperature areas such as those near 0℃. In addition, CWCTs often fail to achieve the designed cooling effect at low air wet-bulb temperatures. A experiment set of CWCT was built, and the performance of the CWCT at low air wet-bulb temperature near 0℃ was investigated. The impact of the operating parameters(air flow rate, cooling water flow rate, and spray water flow rate) on the heat and mass transfer performance of the CWCT was measured and analyzed. The results show the cooling performance of the CWCT at an air wet-bulb temperature 0℃, 2℃, and 4℃ is about 47%–63% of the rated operating condition;the optimal operating parameters of these conditions for the CWCT are just the same as those of the rated operating condition in summer. According to the experimental results, some operating advices are given.

关键词： closed wet cooling tower performance of cooling tower low air wet-bulb temperature rated operating parameters evaluation index

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The closed finite-to-one mappings and their applications

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Applied Mathematics(A Journal of Chinese Universities) 2019年第2期34卷 149-161页

作者： YANG Jie LIN Shou School of Mathematics and Statistics Minnan Normal UniversityZhangzhouFujian 363000China Department of Mathematics Ningde Normal UniversityNingdeFujian 352100China

In this paper, we discuss the closed finite-to-one mapping theorems on generalized metric spaces and their applications. It is proved that point-Gδ properties,?0-snf-countability and csf-countability are invariants and inverse invariants under closed finite-to-one mappings. By the relationships between the weak first-countabilities, we obtain the closed finite-to-one mapping theorems of weak quasi-first-countability, quasi-first-countability, snf-countability, gfcountability and sof-countability. Furthermore, these results are applied to the study of symmetric products of topological spaces.

关键词： finite-to-one mappings closed mappings weak first-countability sn-networks cs-networks symmetric products

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基于Cortex-M4的环面蜗杆检测仪的全闭环控制系统（英文）

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机床与液压 2015年第18期43卷 116-119页

作者：杨永春新疆交通职业技术学院机电工程学院乌鲁木齐831401

针对环面蜗杆检测仪系统控制及定位精度的需要,采用Cortex-M4作为主控制器,控制步进电机驱动载物台运动,步进电机采用闭环控制。光栅尺实时检测XYZ导轨的位置信息,并把光栅信号作为反馈信号,构成闭环运动控制系统,实现坐标系中XYZ轴的... 详细信息

针对环面蜗杆检测仪系统控制及定位精度的需要,采用Cortex-M4作为主控制器,控制步进电机驱动载物台运动,步进电机采用闭环控制。光栅尺实时检测XYZ导轨的位置信息,并把光栅信号作为反馈信号,构成闭环运动控制系统,实现坐标系中XYZ轴的运动和时栅转台旋转的高精度定位。步进电机的驱动采用软硬件细分方法,克服了步进电机爬行和丢步现象。实验表明:该系统采用全闭环控制、步进电机软硬件细分方法,实现了三坐标轴±2μm的精密定位,保证了环面蜗杆检测仪的准确测量。

关键词： Toms worm, Grating ruler, closed loop control, Software and hardware subdivision

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CLS-Miner: efficient and effective closed high-utility itemset mining

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Frontiers of Computer Science 2019年第2期13卷 357-381页

作者： Thu-Lan DAM Kenli LI Philippe FOURNIER-VIGER Quang-Huy DUONG College of Computer Science and Electronic Engineering Hunan University Changsha 410082 China Faculty of Information Technology Hanoi University of Industry Hanoi Vietnam CIC of HPC National University of Defense Technology Changsha 410073 China National Supercomputing Center in Changsha Changsha 410082 China School of Natural Sciences and Humanities Harbin Institute of Technology Shenzhen Graduate School Shenzhen 518055 China Department of Computer Science Norwegian University of Science and Technology Trondheim Norway

High-utility itemset mining (HUIM) is a popular data mining task with applications in numerous domains. However, traditional HUIM algorithms often produce a very large set of high-utility itemsets (HUIs). As a result, analyzing HUIs can be very time consuming for users. Moreover, a large set of HUIs also makes HUIM algorithms less efficient in terms of execution time and memory consumption. To address this problem, closed high-utility itemsets (CHUIs), concise and lossless representations of all HUIs, were proposed recently. Although mining CHUIs is useful and desirable, it remains a computationally expensive task. This is because current algorithms often generate a huge number of candidate itemsets and are unable to prune the search space effectively. In this paper, we address these issues by proposing a novel algorithm called CLS-Miner. The proposed algorithm utilizes the utility-list structure to directly compute the utilities of itemsets without producing candidates. It also introduces three novel strategies to reduce the search space, namely chain-estimated utility co-occurrence pruning, lower branch pruning, and pruning by coverage. Moreover, an effective method for checking whether an itemset is a subset of another itemset is introduced to further reduce the time required for discovering CHUIs. To evaluate the performance of the proposed algorithm and its novel strategies, extensive experiments have been conducted on six benchmark datasets having various characteristics. Results show that the proposed strategies are highly efficient and effective, that the proposed CLS-Miner algorithm outperforms the current state-ofthe- art CHUD and CHUI-Miner algorithms, and that CLSMiner scales linearly.

关键词： utility mining high-utility itemset mining closed itemset mining closed high-utility itemset mining

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