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Structural insights into the assembly of human translesion polymerase complexes

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Protein & Cell 2012年第11期3卷 864-874页

作者： Wei Xie xuan Yang min xu Tao Jiang National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of Sciences15 Datun RoadChaoyang DistrictBeijing 100101China The Graduate University of Chinese Academy of Sciences 19A Yuquan RoadShijingshan DistrictBeijing 100039China

In addition to DNA repair pathways,cells utilize translesion DNA synthesis(TLS)to bypass DNA lesions during *** TLS,Y-family DNA polymerase(Polη,Polκ,Polιand Rev1)inserts specific nucleotide opposite preferred DNA lesions,and then Polζ consisting of two subunits,Rev3 and Rev7,carries out primer ***,we report the complex structures of Rev3-Rev7-Rev1^(CTD) and Rev3-Rev7-Rev1^(CTD)-Polκ^(RIR).These two structures demonstrate that Rev1^(CTD) contains separate binding sites for Polκand *** BIAcore experiments provide additional support for the notion that the interaction between Rev3 and Rev7 increases the affinity of Rev7 and *** also verified through FRET experiment that Rev1,Rev3,Rev7 and Polκ form a stable quaternary complex in vivo,thereby suggesting an efficient switching mechanism where the“inserter”polymerase can be immediately replaced by an“extender”polymerase within the same quaternary complex.

关键词： translesion DNA synthesis Rev1 Polκ Polζ complex structure

Locomotion Performance of the Amphibious Robot on Various Terrains and Underwater with Flexible Flipper Legs

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Journal of Bionic Engineering 2016年第4期13卷 525-536页

作者： Bin Zhong Youcheng Zhou Xiaoxiang Li min xu Shiwu Zhang Department of Precision Machinery and Precision Instrumentation University of Science and Technology of China Hefei 230026 China

Amphibious robots are attracting more and more attentions from researchers worldwide tbr their broad appllcanons m resource exploration, disaster rescue, and reconnaissance. Amphibious robot with transformable flipper-leg composite propul- sion mechanisms can adapt various terrestrial and water environments. In this paper, we explored the locomotion performance of a amphibious robot with flexible flipper legs on various terrains and underwater through dynamical simulation. The influence of the stiffness of the flipper legs on the locomotion performance in various environments was investigated comprehensively. The results indicate that the locomotion with flexible flipper legs is very stable, and the stiffness of the flipper legs has a great impact on the locomotion performance. The verification experiments demonstrate the accuracy of the simulation results. The study facilitates the design of the amphibious robot and indicates that the passively transformable flipper-leg mechanisms also enable amphibious robot to conquer various complex terrestrial environments.

关键词： amphibious robots flexible flipper legs various terrains locomotion performance

Experimental Study of Isopropanol Dehydrogenation over Amorphous Alloy Raney Nickel Catalysts

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Journal of Thermal Science 2013年第6期22卷 613-618页

作者： XIN Fang xu min LI xun-Feng HUAI Xiu-Lan Institute of Engineering Thermophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

The dehydrogenation reaction of isopropanol occurring at low temperature is of great industrial importance. It is a key procedure in isopropanol/acetone/hydrogen chemical heat pump system. An experimental investigation was performed to study the behavior of the liquid phase dehydrogenation of isopropanol over amorphous alloy Raney nickel catalysts. Un-promoted and promoted catalysts were used and their performances were compared under various catalyst amounts, acetone content in the reactant and reaction temperature ranging from 348 K to 355 *** is found that there exists an optimum catalyst concentration which is about 0.34 g in 300 ml isopropanol. The temperature has evident effect on the reaction. The presence of activities of Fe-promoted catalyst decrease slightly compared to the un-promoted catalyst when the temperature are 348 K and 351 K. Besides, the reaction rate decreases almost linearly with the increase of acetone volume fraction in the reactant.

关键词： Chemical heat pump Liquid-phase dehydrogenation Isopropanol

A New High-Precision and Lightweight Detection Model for Illegal Construction Objects Based on Deep Learning

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Tsinghua Science and Technology 2024年第4期29卷 1002-1022页

作者： Wenjin Liu Lijuan Zhou Shudong Zhang Ning Luo min xu School of Cyberspace Security(School of Cryptology) Hainan UniversityHaikou 570228China School of Information Engineering Capital Normal UniversityBeijing 100048China

Illegal construction has caused serious harm around the world. However, current methods are difficult to detect illegal construction activities in time, and the calculation complexity and the parameters of them are large. To solve these challenges, a new and unique detection method is proposed, which detects objects related to illegal buildings in time to discover illegal construction activities. Meanwhile, a new dataset and a high-precision and lightweight detector are proposed. The proposed detector is based on the algorithm You Only Look Once (YOLOv4). The use of DenseNet as the backbone of YDHNet enables better feature transfer and reuse, improves detection accuracy, and reduces computational costs. Meanwhile, depthwise separable convolution is employed to lightweight the neck and head to further reduce computational costs. Furthermore, H-swish is utilized to enhance non-linear feature extraction and improve detection accuracy. Experimental results illustrate that YDHNet realizes a mean average precision of 89.60% on the proposed dataset, which is 3.78% higher than YOLOv4. The computational cost and parameter count of YDHNet are 26.22 GFLOPs and 16.18 MB, respectively. Compared to YOLOv4 and other detectors, YDHNet not only has lower computational costs and higher detection accuracy, but also timely identifies illegal construction objects and automatically detects illegal construction activities.

关键词： object detection lightweight illegal buildings illegal construction objects high-precision

Negative efficacy of antidepressants in pharmacotherapy of child and adolescent depression

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World Journal of Psychiatry 2025年第1期15卷 32-36页

作者： min xu Hai-Ying Jin Feng-Li Sun Wei-Dong Jin Department of Psychiatry Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Psychiatry Tongde Hospital of Zhejiang ProvinceHangzhou 310012Zhejiang ProvinceChina Department of Psychiatry Zhejiang Provincial Mental Health CenterHangzhou 311122Zhejiang ProvinceChina

Antidepressants are the main drugs used to treat depression,but they have not been shown to be effective in the treatment of child and adolescent ***,many adolescent depression treatment guidelines still recommend the use of antidepressants,especially specific serotonin re-uptake *** studies have suggested that antidepressants have little therapeutic effect but many side effects,such as switching to mania,suicide,and non-suicidal self injury(NSSI),in the treatment of child and adolescent *** the process of developing guidelines,drug recommendations should not only focus on impro-ving symptoms,but they should also consider potential side *** review discusses the serious side effects of antidepressants,including switching to mania,suicide,and NSSI.

关键词： Child depression Adolescent depression Antidepressant Switch Suicide Non-suicidal self injury

Model of Primary Austenite Dendrite Structure in Hypoeutectic Cast Iron

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Journal of Iron and Steel Research International 2003年第1期10卷 33-35页

作者： WU xu-min YU Xiao-hua xu Jun ZHANG You-ling Wuhan University of Technology

The solidification of primary austenite in hypocutcctic gray cast iron was studied by stepped grinding and quantitative *** dendrite structure of primary austenite can be described by three models:typical dendrite crystal model,metamorphic dendrite crystal model and network dendrite crystal *** dendrite crystals formed according to 3rd model is much more than those formed according to other models in this *** primary austenites are connected each other,and the primary stems of austenite could be regarded as secondary arms and vice versa.

关键词： hypoeutectic cast iron primary austenite dendrite structure

The formation and repair of DNA double-strand breaks in mammalian meiosis

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Asian Journal of Andrology 2021年第6期23卷 572-579页

作者： Wei Qu Cong Liu Ya-Ting xu Yu-min xu Meng-Cheng Luo Hubei Provincial Key Laboratory of Developmentally Originated Disease School of Basic Medical SciencesWuhan UniversityWuhan 430072China

Programmed DNA double-strand breaks(DSBs)are necessary for meiosis in mammals.A sufficient number of DSBs ensure the normal pairing/synapsis of homologous *** DSB repair undermines meiosis,leading to sterility in *** DSBs that initiate recombination are repaired as crossovers and noncrossovers,and crossovers are required for correct chromosome ***,the placement,timing,and frequency of crossover formation must be tightly ***,mutations in many genes related to the formation and repair of DSB result in infertility in *** mutations cause nonobstructive azoospermia in men,premature ovarian insufficiency and ovarian dysgenesis in ***,we have illustrated the formation and repair of DSB in mammals,summarized major factors influencing the formation of DSB and the theories of crossover regulation.

关键词： azoospermia crossover DSB meiosis recombination

Effect of welding process on the microstructure and properties of dissimilar weld joints between low alloy steel and duplex stainless steel

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International Journal of minerals,Metallurgy and Materials 2012年第6期19卷 518-524页

作者： Jing Wang min-xu Lu Lei Zhang Wei Chang Li-ning xu Li-hua Hu Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China Research Institute of China National Offshore Oil Corporation Beijing 100027 China

To obtain high-quality dissimilar weld joints, the processes of metal inert gas （MIG） welding and tungsten inert gas （TIG） welding for duplex stainless steel （DSS） and low alloy steel were compared in this paper. The microstructure and corrosion morphology of dissimilar weld joints were observed by scanning electron microscopy （SEM）; the chemical compositions in different zones were detected by en- ergy-dispersive spectroscopy （EDS）; the mechanical properties were measured by microhardness test, tensile test, and impact test; the corro- sion behavior was evaluated by polarization curves. Obvious concentration gradients of Ni and Cr exist between the fusion boundary and the type II boundary, where the hardness is much higher. The impact toughness of weld metal by MIG welding is higher than that by TIG weld- ing. The corrosion current density of TIG weld metal is higher than that of MIG weld metal in a 3.5wt% NaC1 solution. Galvanic corrosion happens between low alloy steel and weld metal, revealing the weakness of low alloy steel in industrial service. The quality of joints pro- duced by MIG welding is better than that by TIG welding in mechanical performance and corrosion resistance. MIG welding with the filler metal ER2009 is the suitable welding process for dissimilar metals jointing between UNS $31803 duplex stainless steel and low alloy steel in practical application.

关键词： dissimilar metals welds stainless steel alloy steel microstructure mechanical properties corrosion

Variation of sea ice and perspectives of the Northwest Passage in the Arctic Ocean

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Advances in Climate Change Research 2021年第4期12卷 447-455页

作者： CHEN Jin-Lei KANG Shi-Chang GUO Jun-ming xu min ZHANG Zhi-min State Key Laboratory of Cryosphere Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Centre for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing100101China Gansu Construction Vocational Technology College Lanzhou730000China

The continued warming of the Arctic atmosphere and ocean has led to a record retreat of sea ice in the last *** retreat has increased the probability of the opening of the Arctic Passages in the near *** Northwest Passage(NWP)is the most direct shipping route between the Atlantic and Pacific Oceans,producing notable economic *** variations of sea ice and its influencing factors from a high-resolution unstructured-grid finite-volume community ocean model were investigated along the NWP in 1988-2016,and the accessibility of the NWP was assessed under shared socioeconomic pathways(SSP245 and 585)and two vessel classes with the Arctic transportation acces-sibility model in *** ice thickness has decreased with increasing seawater temperature and salinity,especially within the Canadian Arctic Archipelago(CAA)in 1988-2016,which has facilitated the opening of the *** ship navigation is projected to be possible for polar class 6 ships in August-December in 2021-2025,after when it may extends to July under SSP585 in 2026-2030,while open water ships will not be able to pass through the NWP until September in mid-21st *** navigability of the NWP is mainly affected by the ice within the *** the accessibility of the Parry Channel,the west part is worse than that of the eastern part,especially in the Viscount-Melville Sound.

关键词： Arctic Sea ice Northwest passage Canadian arctic archipelago Strait