检索结果-南通市图书馆

PRSS50-mediated inhibition of MKP3/ERK signaling is crucial for meiotic progression and sperm quality

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

动物学研究 2024年第5期 1037页

作者： Chun-Xue Niu Jia-Wei Li Xiao-Li Li Lin-Lin Zhang Yan Lang Zhen-Bo Song Chun-Lei Yu Xiao-guang Yang Hai-Feng Zhao Jia-Ling Sun Li-Hua Zheng Xue wang Ying Sun Xiao-Hong Han guan-nan wang Yong-Li Bao National Engineering Laboratory for Druggable Gene and Protein Screening Northeast Normal University China International Joint Research Center for Human Stem Cell Bank Northeast Normal University Jilin Institute for Drug Control

Serine protease 50（PRSS50/TSP50） is highly expressed in spermatocytes. Our study investigated its role in testicular development and spermatogenesis. Initially,PRSS50 knockdown was observed to impair DNA synthesis in spermatocytes. To further explore this, we generated PRSS50 knockout(Prss50-/-) mice（Mus musculus）, which exhibited abnormal spermatid nuclear compression and reduced male fertility. Furthermore,dysplastic seminiferous tubules and decreased sex hormones were observed in 4-week-old Prss50-/-mice,accompanied by meiotic progression defects and increased apoptosis of spermatogenic cells. Mechanistic analysis indicated that PRSS50 deletion resulted in increased phosphorylation of extracellular signal-regulated protein kinases 1 and 2（ERK1/2） and elevated levels of MAP kinase phosphatase 3（MKP3）, a specific ERK antagonist, potentially accounting for testicular dysplasia in adolescent Prss50-/-mice. Taken together, these findings suggest that PRSS50 plays an important role in testicular development and spermatogenesis, with the MKP3/ERK signaling pathway playing a significant role in this process.

关键词：

来源：博看期刊

Numerical simulation of partial-interaction load-deflection behavior of corroded reinforced concrete beams based on a segmental approach and evaluation of reinforcement corrosion level

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第4期21卷 280-293页

作者： Qian FENG guan-nan wang Yong-ping ZHANG Rong-qiao XU College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China School of Mechanics and Engineering Science Shanghai UniversityShanghai 200444China

Corrosion of reinforcement has a significant effect on the deformation of reinforced concrete beams by deteriorating the bond-slip characteristics, diminishing the cross-sectional area of reinforcement, and causing cracking. The traditional way of quantifying the load capacity and simulating deflection is the moment-curvature(M/χ) approach. The problem is that the M/χ approach is semi-empirical after cracking as it is strain-based and cannot allow for tension stiffening. This paper introduces the new displacement-based moment-rotation(M/θ) approach which directly simulates the development of cracks and hence allows for tension stiffening. This M/θ approach is then used to predict the load-deflection behavior of reinforced concrete beams with corrosion effect by incorporating the corrosion-affected bond-slip model. The bond-slip model only considers the corrosion effect but ignores the confinement effect. It is used here as an example to describe the procedure of how to quantify the corrosion effect on reinforced concrete beam behavior. The load-deflection curves obtained from the numerical simulation show a good agreement with test results. For reinforced concrete beams with confinement, the only difference is to replace the bond-slip model with the one which includes both corrosion and stirrup effects. Additionally, the paper shows how to use the M/θ approach with the bond-slip model to predict the real corrosion level of reinforcement in some tests in which only the theoretical corrosion levels are provided.

关键词： Reinforced concrete Corrosion Partial interaction Load-deflection Tension-stiffening Bond-slip

Remaining Useful Life Prediction Method for Multi-Component System Considering Maintenance:Subsea Christmas Tree System as A Case Study

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing CAI Bao-ping FAN Hong-yan wang guan-nan RAO Xi GE Weifeng SHAO Xiao-yan LIU Yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health ***,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating *** complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL *** RUL prediction method for a multi-omponent system based on the Wiener process considering maintenance is *** performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data *** on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance *** example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life Wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

Structural Engineering of Anode Materials for Low-Temperature Lithium-Ion Batteries:Mechanisms,Strategies,and Prospects

在线全文

学校读者我要写书评

暂无评论

nano-Micro Letters 2024年第8期16卷 169-195页

作者： guan wang Guixin wang Linfeng Fei Lina Zhao Haitao Zhang Beijing Key Laboratory of Ionic Liquids Clean Process Institute of Process EngineeringChinese Academy of SciencesBeijing 100190People’s Republic of China School of Chemical Engineering Sichuan UniversityChengdu 610065People’s Republic of China School of Energy Materials and Chemical Engineering Hefei UniversityHefei 230601People’s Republic of China School of Materials Science and Engineering Nanchang UniversityNanchang 330031People’s Republic of China Key Laboratory of Polymer and Catalyst Synthesis Technology of Liaoning Province School of Environmental and Chemical EngineeringShenyang University of TechnologyShenyang 110870People’s Republic of China

The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical ***,extensive efforts have been contributed to explore novel anode materials with high electronic conductivity and rapid Li^(+)diffusion kinetics for achieving favorable low-temperature performance of ***,we try to review the recent reports on the synthesis and characterizations of low-temperature anode ***,we summarize the underlying mechanisms responsible for the performance degradation of anode materials at subzero ***,detailed discussions concerning the key pathways(boosting electronic conductivity,enhancing Li^(+)diffusion kinetics,and inhibiting lithium dendrite)for improving the low-temperature performance of anode materials are ***,several commonly used low-temperature anode materials are briefly ***,recent progress in the engineering of these low-temperature anode materials is summarized in terms of structural design,morphology control,surface&interface modifications,and multiphase ***,the challenges that remain to be solved in the field of low-temperature anode materials are *** review was organized to offer valuable insights and guidance for next-generation LIBs with excellent low-temperature electrochemical performance.

关键词： Low-temperature performance Anode materials Microstructural regulations Surface modifications

Hadoop-based secure storage solution for big data in cloud computing environment

在线全文

学校读者我要写书评

暂无评论

Digital Communications and Networks 2024年第1期10卷 227-236页

作者： Shaopeng guan Conghui Zhang Yilin wang Wenqing Liu School of Information and Electronic Engineering Shandong Technology and Business UniversityYantai264003China

In order to address the problems of the single encryption algorithm,such as low encryption efficiency and unreliable metadata for static data storage of big data platforms in the cloud computing environment,we propose a Hadoop based big data secure storage ***,in order to disperse the NameNode service from a single server to multiple servers,we combine HDFS federation and HDFS high-availability mechanisms,and use the Zookeeper distributed coordination mechanism to coordinate each node to achieve dual-channel ***,we improve the ECC encryption algorithm for the encryption of ordinary data,and adopt a homomorphic encryption algorithm to encrypt data that needs to be *** accelerate the encryption,we adopt the dualthread encryption ***,the HDFS control module is designed to combine the encryption algorithm with the storage *** results show that the proposed solution solves the problem of a single point of failure of metadata,performs well in terms of metadata reliability,and can realize the fault tolerance of the *** improved encryption algorithm integrates the dual-channel storage mode,and the encryption storage efficiency improves by 27.6% on average.

关键词： Big data security Data encryption Hadoop Parallel encrypted storage Zookeeper

Quasi-two-dimensional strong liquid-like dynamics of surface atoms in metallic glasses

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 102-109页

作者： Bing wang Xuanqiao Gao Rui Su Pengfei guan School of Physical Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Innovation Center NPU Chongqing Northwestern Polytechnical UniversityChongqing 401135China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China Northwest Institute for Nonferrous Metal Research Xi'an 710016China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi University Hangzhou 310018China Beijing Computational Science Research Center Beijing 100093China

The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simulation models and laboratory-made samples, the atomic-scale behaviors of the fast surface dynamics of MGs in experiments remain uncertain. Herein, we prepared model MG films with notable variations in thermal stability using a recently developed efficient annealing protocol, and investigated their atomic-scale dynamics systematically. We found that the dynamics of surface atoms remain invariant, whereas the difference in dynamical heterogeneity between surface and interior regions increases with the improvement of thermal stability. This can be associated with the more pronounced correlation between atomic activation energy spectra and depth from the surface in samples with higher thermal stability. In addition, dynamic anisotropy appears for surface atoms, and their transverse dynamics are faster than normal components, which can also be interpreted by activation energy spectra. Our results reveal the presence of strong liquid-like atomic dynamics confined to the surface of laboratory-made MGs, illuminating the underlying mechanisms for surface engineering design, such as cold joining by ultrasonic vibrations and superlattice growth.

关键词： metallic glasses thermal stability invariant surface dynamics potential energy landscape dynamic anisotropy and heterogeneity

Recent advances in the culture-independent discovery of natural products using metagenomic approaches

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Natural Medicines 2024年第2期22卷 100-111页

作者： SHEN Yiping LIU nan wang Zongqiang Laboratory of Microbial Drug Discovery China Pharmaceutical UniversityNanjing 211198China

Natural products derived from bacterial sources have long been pivotal in the discovery of drug ***,the cultivation of only about 1%of bacteria in laboratory settings has left a significant portion of biosynthetic diversity hidden within the genomes of uncultured *** in sequencing technologies now enable the exploration of genetic material from these metagenomes through culture-independent *** approach involves extracting genetic sequences from environmental DNA and applying a hybrid methodology that combines functional screening,sequence tag-based homology screening,and bioinformatic-assisted chemical *** this process,numerous valuable natural products have been identified and synthesized from previously uncharted metagenomic *** paper provides an overview of the recent advancements in the utilization of culture-independent techniques for the discovery of novel biosynthetic gene clusters and bioactive small molecules within metagenomic libraries.

关键词： Metagenomics Culture-independent approach Natural product Functional screening Sequence tag-based homology screening Syn-BNP

Reduced magma generation and its implications for the Pulang giant porphyry Cu-polymetallic deposit in Northwest Yunnan,China

在线全文

学校读者我要写书评

暂无评论

Acta Geochimica 2024年第4期43卷 802-813页

作者： Jingwei guan Tao Ren Lei wang Shenjin guan Lianrong Wu Baosheng Shi Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093People’s Republic of China Diqing Nonferrous Metals Co. LtdShangri-La 674400People’s Republic of China

The Pulang giant porphyry Cu-Mo polymetallic deposit is located in the Zhongdian area in the center of the Sanjiang Tethys tectonic domain,which was formed by the westward subduction of the Garze-Litang oceanic slab beneath the Zhongza ***-pyrrhotite-pyritemolybdenite occurs as disseminations,veins,veinlets,and stockworks distributed in the K-silicate alteration zone in the monzonite porphyry,which is superimposed by *** chemical compositions of biotite and amphibole analyzed by electron probe microanalysis(EPMA)indicate that the ore-forming magma and exsolved fluids experienced a continuous decrease in the oxygen fugacity(fO_(2)).Primary amphibolite and biotite(type I)crystallized at relatively high temperatures(744-827°C)and low fO_(2)(log fO_(2)=−12.26 to−11.91)during the magmatic *** fluids exsolved from the magma have a relatively lower temperature(621-711°C)and fO_(2)(log fO_(2)=−14.36 to−13.32)than the original *** addition,the presence of a high abundance of pyrrhotite and an insufficiency of primary magnetite and sulfate in the ore(i.e.,anhydrite and gypsum)indicate that the deposit may be a reduced porphyry *** and fluid fO_(2)results,combined with previous research on magmatic fO_(2)at the Pulang deposit,indicate that the magma associated with the reduced Pulang ore assemblages was initially generated as a highly oxidized magma that was subsequently reduced by sedimentary rocks of the Tumugou Formation.

关键词： Porphyry deposit Oxygen fugacity(fO_(2)) Contamination of surrounding rock Pulang Zhongdian arc

Utilizing a metal-forging inspired chain combing strategy to enhance properties and expand applications of Nylon 66 plastic via heat inducing

在线全文

学校读者我要写书评

暂无评论

nano Research 2024年第3期17卷 2164-2171页

作者： Junyu Yang Jiangwei Zhang nan wang guangyuan Zhou Division of Energy Materials Daglian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Innovation Center of Energy Material and Chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot 010021China

The mechanical properties of engineering plastics can be enhanced through effective surface mechanical treatment(SMT),which can be applied to various types of engineering plastics,eliminating the limitations of conventional polymer processing and could potentially extend their applications and improve their performance and reliability as structural-functional *** by metal forging,this work proposes a simple and effective SMT strategy to enhance the mechanical properties of polyamide 66(PA66).Tensile tests have shown that SMTed PA66 samples exhibit significant improvements in both Young’s modulus and ultimate tensile strength(UTS),with a 2104 MPa Young’s modulus,almost double that of the pristine samples,and a 35.56%increase in UTS,reaching 183 ***,the modulus within the localized SMTed surface layer could reach up to 14 GPa,which is approximately 14 times higher than that of the pristine *** Vickers hardness within the localized SMTed surface layer can be doubled,reaching 10.72 Hv,and the crystallinity can increase by approximately 20%compared to the untreated ***,force field molecular dynamics(FFMD)simulations were conducted to investigate the ternary relationship between the SMT method,PA66’s molecular structure,and its *** combination of MD simulations and versatile structural characterizations provides evidence that the SMT method’s mechanism,under heat induction,results in a chain-combing procedure that changes the polymer’s molecular morphology microscopically and enhances its mechanical properties macroscopically.

关键词： Nylon 66 mechanical properties hardness crystallinity structural characterizations molecular dynamics simulation