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The stable Auslander-Reiten components of certain monomorphism categories

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Science China Mathematics 2024年第3期67卷 505-526页

作者： Rasool Hafezi yi zhang School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China

Let Λ be an Artin algebra and let Gprj-Λ denote the class of all the finitely generated Gorenstein projective Λ-modules. In this paper, we study the components of the stable Auslander-Reiten quiver of a certain subcategory of the monomorphism category S(Gprj-Λ) containing boundary vertices. We describe the shape of such components. It is shown that certain components are linked to the orbits of an auto-equivalence on the stable category Gprj. In particular, for the finite components, we show that under certain mild conditions,their cardinalities are divisible by 3. We see that this three-periodicity phenomenon reoccurs several times in the paper.

关键词： monomorphism category almost split sequence Auslander-Reiten quiver Gorenstein projective module

Different El Niño Flavors and Associated Atmospheric Teleconnections as Simulated in a Hybrid Coupled Model

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Advances in Atmospheric Sciences 2024年第5期41卷 864-880页

作者： Junya HU Hongna WANG chuan GAO Rong-Hua zhang Key Laboratory of Ocean Circulation and Waves Institute of Oceanologyand Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Laoshan Laboratory Qingdao 266237China

A previously developed hybrid coupled model(HCM)is composed of an intermediate tropical Pacific Ocean model and a global atmospheric general circulation model(AGCM),denoted as *** this study,different El Niño flavors,namely the Eastern-Pacific(EP)and Central-Pacific(CP)types,and the associated global atmospheric teleconnections are examined in a 1000-yr control simulation of the *** HCMAGCM indicates profoundly different characteristics among EP and CP El Niño events in terms of related oceanic and atmospheric variables in the tropical Pacific,including the amplitude and spatial patterns of sea surface temperature(SST),zonal wind stress,and precipitation *** SST budget analysis indicates that the thermocline feedback and zonal advective feedback dominantly contribute to the growth of EP and CP El Niño events,*** to the shifts in the tropical rainfall and deep convection during EP and CP El Niño events,the model also reproduces the differences in the extratropical atmospheric responses during the boreal *** particular,the EP El Niño tends to be dominant in exciting a poleward wave train pattern to the Northern Hemisphere,while the CP El Niño tends to preferably produce a wave train similar to the Pacific North American(PNA)*** a result,different climatic impacts exist in North American regions,with a warm-north and cold-south pattern during an EP El Niño and a warm-northeast and cold-southwest pattern during a CP El Niño,*** modeling result highlights the importance of internal natural processes within the tropical Pacific as they relate to the genesis of ENSO diversity because the active ocean–atmosphere coupling is allowed only in the tropical Pacific within the framework of the HCMAGCM.

关键词： hybrid coupled model tropical Pacific Ocean global atmosphere Eastern/Central-Pacific El Niño atmospheric teleconnections

Alkyl Radical Initiated Cyclization/Cascade for Synthesizing Lactam-Substituted Alkyl Sulfones

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Chinese Journal of Chemistry 2024年第16期42卷 1853-1859页

作者： Li-Jun Wu Kai-yi zhang Pei Yang chuan-Chong Peng Jin-Hui Liu Qing Li Da-Zhi Sun Shuangfeng yin College of Sciences Central South University of Forestry and TechnologyChangshaHunan410004 China School of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhotInner Mongolia010021 China

An alkyl radical initiated cyclization/tandem reaction of alkyl bromides and alkyl electrophiles by using potassium metabisulphite(K_(2)S_(2)O_(5))as a connector is developed for the synthesis of various lactam-substituted alkyl ***,this process does not require a metal catalyst or metal powder reductant,highlighting its environmentally friendly *** reaction demonstrates outstanding substrate adaptability and a high tolerance towards diverse functional ***,the biologically active molecules and commercially available drugs with a late-stage modification are also highly compatible with this *** studies revealed that the reaction proceeds through a single-step process involving intramolecular radical cyclization,"SO_(2)"insertion,and external alkyl incorporation.

关键词： Alkyl radical Metal-free catalyzed Cyclization/cascade Potassium metabisulphite Electrophiles Alkyl sulfones Lactams Alkyl bromides Sodium formate

Crystalline-amorphous M@MN_x(M=Co,Fe,Ni)encapsulated in nitrogen-doped carbon for enhanced efficient and durable hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1547-1556页

作者： Yang Yang Xiao-chuan Duan Shao-Hui Guo Xian-Ming zhang College of Materials Science and Engineering College of ChemistryKey Laboratory of Interface Science and Engineering in Advanced MaterialsTaiyuan University of TechnologyYuci030600China

Developing earth-abundant electrocatalysts for hydrogen evolution reaction(HER)is important for the sustainable energy ***,efficient and stable heterocatalysts consisting of crystalline-amorphous M@MN_(x)(M=Co,Fe,Ni)encapsulated in N-doped carbon layers supported with N-doped graphene sheets(denoted as M@MN_(x)@NC-NG)are synthesized by facile hydrothermal reaction and nitridation *** the nitriding process,metal ions in M(tzbc)_2(H_(2)O)_4(tzbc=4-(1H-1,2,4-triazol-1-yl)benzoic acid)complexes are reduced to crystalline M cores,accompanied by the formation of amorphous MN_(x)shells;the tzbc ligands are insitu carbonized to form outermost N-doped carbon(NC)layers that connect with inner MN_(x)via M-N-C motifs inherited from the complex precursors and inhibit the transition of MN_(x)from amorphous to crystalline *** Co@CoN_(x)@NC-NG catalyst exhibits excellent HER activity with small overpotentials of 45 and 64 mV at a cathode current density of 10 mA·cm^(-2)and low Tafel slopes of 40 and 85 mV·dec^(-1)in 0.5 mol·L^(-1)H_(2)SO_4 and1.0 mol·L^(-1)KOH electrolytes,*** Co@CoN_(x)@NC-NG retains 97%of the initial overpotential after 100,000 s in both acidic and alkaline *** outstanding HER performance originates from the crystalline-amorphous Co@CoN_(x)that redistributes electrons around the heterointerfaces,facilitating the conversion process of H^(+)/H_(2)O to hydrogen and thereby promoting HER *** outermost NC layers serve as the armor of Co@CoN_(x),and graphene nanosheets act as carriers of egg-like Co@CoN_(x)@NC and conduction paths for electron shuttles,ensuring stable and continuous electrocatalytic hydrogen production.

关键词： Hydrogen evolution reaction Electrocatalysts Iron group metals Heterojunction Crystalline-amorphous structure

Cordyceps as potential therapeutic agents for atherosclerosis

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Journal of Integrative Medicine 2024年第2期22卷 102-114页

作者： yi zhang Si-jing Liu School of Marxism Chengdu University of Traditional Chinese MedicineChengdu 61137Sichuan ProvinceChina College of Medical Technology Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina Chongqing Key Laboratory of Sichuan-Chongqing Co-construction for Diagnosis and Treatment of Infectious Diseases with Integrated Chinese and Western Medicine Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina

Atherosclerosis is a leading cause of mortality and morbidity *** the challenges in managing atherosclerosis,researchers continue to investigate new treatments and complementary *** is a traditional Chinese medicine that has recently gained attention as a potential therapeutic agent for *** studies have demonstrated the effectiveness of cordyceps in treating atherosclerosis through various pharmacological actions,including anti-inflammatory and antioxidant activities,lowering cholesterol,inhibiting platelet aggregation,and modulating apoptosis or autophagy in vascular endothelial ***,the current misuse of the terms cordyceps and Ophiocordyceps sinensis has caused confusion among researchers,and complicated the current academic research on *** review focuses on the chemical composition,pharmacological actions,and underlying mechanisms contributing to the anti-atherosclerotic effects of cordyceps and the mycelium of Ophiocordyceps *** review provides a resource for the research on the development of new drugs for atherosclerosis from cordyceps.

关键词： Atherosclerosis Cordyceps Ophiocordyceps sinensis

Gene therapy for monogenic disorders: challenges, strategies, and perspectives

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Journal of Genetics and Genomics 2024年第2期51卷 133-143页

作者： yi zhang Zhi-ying Wu Department of Medical Genetics and Center for Rare Diseases Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China Department of Neurology Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China Key Laboratory of Medical Neurobiology of Zhejiang Province HangzhouZhejiang 310009China

Monogenic disorders refer to a group of human diseases caused by mutations in single genes. While disease-modifying therapies have offered some relief from symptoms and delayed progression for some monogenic diseases, most of these diseases still lack effective treatments. In recent decades, gene therapy has emerged as a promising therapeutic strategy for genetic disorders. Researchers have developed various gene manipulation tools and gene delivery systems to treat monogenic diseases. Despite this progress, concerns about inefficient delivery, persistent expression, immunogenicity, toxicity, capacity limitation, genomic integration, and limited tissue specificity still need to be addressed. This review gives an overview of commonly used gene therapy and delivery tools, along with the challenges they face and potential strategies to counter them.

关键词： Gene therapy Monogenic diseases Geneediting Genedelivery Challenges

Policy Network-Based Dual-Agent Deep Reinforcement Learning for Multi-Resource Task Offloading in Multi-Access Edge Cloud Networks

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China Communications 2024年第4期21卷 53-73页

作者： Feng chuan zhang Xu Han Pengchao Ma Tianchun Gong Xiaoxue School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Institute of Intelligent Communication and Network Security Chongqing University of Posts and TelecommunicationsChongqing 400065China Key Laboratory of Big Data Intelligent Computing Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Information Engineering Guangdong University of TechnologyGuangzhou 510006China

The Multi-access Edge Cloud(MEC) networks extend cloud computing services and capabilities to the edge of the networks. By bringing computation and storage capabilities closer to end-users and connected devices, MEC networks can support a wide range of applications. MEC networks can also leverage various types of resources, including computation resources, network resources, radio resources,and location-based resources, to provide multidimensional resources for intelligent applications in 5/***, tasks generated by users often consist of multiple subtasks that require different types of resources. It is a challenging problem to offload multiresource task requests to the edge cloud aiming at maximizing benefits due to the heterogeneity of resources provided by devices. To address this issue,we mathematically model the task requests with multiple subtasks. Then, the problem of task offloading of multi-resource task requests is proved to be NP-hard. Furthermore, we propose a novel Dual-Agent Deep Reinforcement Learning algorithm with Node First and Link features(NF_L_DA_DRL) based on the policy network, to optimize the benefits generated by offloading multi-resource task requests in MEC networks. Finally, simulation results show that the proposed algorithm can effectively improve the benefit of task offloading with higher resource utilization compared with baseline algorithms.

关键词： benefit maximization deep reinforcement learning multi-access edge cloud task offloading

Different Types of Bone Fractures Observed by Terahertz Time-Domain Spectroscopy

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Acta Mechanica Solida Sinica 2024年第3期37卷 468-477页

作者： Minghao zhang Xianjia Meng Zhiyong Wang chuanyong Qu chuan Qu Donghui Fu Department of Mechanics Tianjin UniversityTianjin300072China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin300072China

Microcracks are common in compact bone,but their continued propagation can lead to macroscopic *** microcracks cannot be visualized radiographically,necessitating alternative noninvasive methods to identify excessive microcracking and prevent *** this study,terahertz time-domain spectroscopy(THz-TDS)was used to examine bone interiors near cracks resulting from loading in bovine tibia *** loading configurations,such as impact,quasi-static loading,and fatigue loading,known to induce different types of micro-scale damage,were *** values of refractive index and absorption coefficient of the bone samples were then determined from the THz-TDS spectra acquired before loading and after *** study revealed that different loading configurations led to varying terahertz optical coefficients associated with various types of bone ***,the refractive index notably increased under fatigue loading but remained relatively stable during quasi-static *** absorption coefficient of bone decreased only under fatigue ***,samples were subjected to axial and radial impacts without sustaining *** indicated that in the undamaged state,the change in refractive index was smaller compared to after impact failure,while the change in absorption coefficient remained consistent after *** radial impact loading,changes in refractive index and absorption coefficient were significantly more pronounced than under axial *** to loading,the measured value of refractive index was 2.72±0.11,and the absorption coefficient was 6.33±0.09 mm^(−1)at 0.5 THz.

关键词： Terahertz time-domain spectroscopy Bone Microdamage Noninvasive method

An analytical model of hot rolling force for a thick plate by combining globally optimal approximation yield criterion and egg-circular velocity field

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Journal of Iron and Steel Research International 2024年第3期31卷 647-659页

作者： Shun-hu zhang yi zhang Wen-hao Tian Yan Li Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

For the sake of solving the problem that it is difficult to be integrated for the Mises specific plastic power due to its nonlinearity,a new linear criterion,named the globally optimal approximation criterion,is constructed by the polygonal approximation to the Mises *** new criterion is proved to be the linear function of the principal stress componentsσ1,σ2 andσ3 and the trajectory of it on theπ-plane is a non-equiangular but equilateral dodecagon intersecting the Mises *** theoretical results of the current criterion described by the Lode stress parameters are in excellent accordance with the experimental ***,according to the trend that the metallic flow velocity between rollers aggrandizes gradually from the inlet to the outlet during the hot rolling of a thick plate,a biomimetic velocity field is proposed in which the horizontal velocity component fits the egg-circular curve *** velocity field and its simulated results agree quite ***,using the determined linear criterion,energy analysis of the constructed velocity field is utilized to obtain the interior deformation power,while the vector decomposition approach is utilized to obtain the frictional power and shear *** this basis,the overall power is obtained and the analytical solutions are generated for the rolling torque,rolling force and the coefficient of the stress state under different egg curves by minimizing the neutral ***,the parameter optimization of the characteristic parameterρwhich affects the slope of the egg-circular curve is carried out and the best egg-circular curve which can minimize the energy consumption is *** best agreement between the theoretical and observed values of rolling force and rolling torque is under this curve,and the mean relative errors of the rolling torque and rolling force are no more than 2.93%,while the maximum error is no more than 8.35%.

关键词： yield criterion Plastic deformation Rolling force Velocity field Analytical solution