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含卟啉聚肽的合成及其自组装行为研究

高分子学报 2024年第2期55卷 172-181页

作者：王寅超郑家豪张伟安蔡春华林嘉平华东理工大学材料科学与工程学院上海200237

以带有炔丙基端基的聚(γ-苄基-L-谷氨酸酯)(PBLG)和含单叠氮基团的卟啉衍生物(TFPP-N3)为反应物,利用点击反应,合成了含卟啉聚肽(TFPP-PBLG).运用核磁共振氢谱(1H-NMR)、傅里叶变换红外光谱(FTIR)、紫外-可见光光度计(UV-Vis)和凝胶渗... 详细信息

以带有炔丙基端基的聚(γ-苄基-L-谷氨酸酯)(PBLG)和含单叠氮基团的卟啉衍生物(TFPP-N3)为反应物,利用点击反应,合成了含卟啉聚肽(TFPP-PBLG).运用核磁共振氢谱(1H-NMR)、傅里叶变换红外光谱(FTIR)、紫外-可见光光度计(UV-Vis)和凝胶渗透色谱(GPC)表征了聚合物的结构、分子量及其分布.采用有机共溶剂溶解、选择性溶剂(水)诱导组装并透析的方法,制备得到碗状胶束.通过扫描电子显微镜(SEM)、原子力显微镜(AFM)、透射电子显微镜(TEM)、动态激光光散射(DLS)和小角X射线散射仪(SAXS)表征了组装体的形貌与结构,并探究其自组装机理.结果表明,卟啉基团间的π-π堆叠作用使得胶束具有较为稳定结构;在透析过程中,胶束内部的溶剂向外扩散,导致胶束塌陷形成了纳米碗.增加PBLG链段长度,会进一步提高初始胶束的结构稳定性,导致在透析过程中胶束结构保持完整不能得到纳米碗.初始胶束的结构稳定性是决定其在后续溶剂交换过程中是否发生凹陷从而形成纳米碗的关键.

关键词：聚肽卟啉点击反应自组装碗状胶束

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跨境电商助力“双循环”经济发展研究与探讨

长春金融高等专科学校学报 2024年第3期 61-68页

作者：贾林平郭炬郭雪琪北京经济管理职业学院教务处北京100102 北京经济管理职业学院临空经济管理学院北京100102 澳门科技大学商学院中国澳门999078

近年来,依托互联网技术和数字经济的发展,在国家政策的积极引导和基础设施的全面建设下,跨境电子商务产业发展势头强劲,已成为我国重要的贸易新业态、新模式,也是全球经济增长的新动能、新引擎,在国内国际“双循环”经济发展中扮演着重... 详细信息

近年来,依托互联网技术和数字经济的发展,在国家政策的积极引导和基础设施的全面建设下,跨境电子商务产业发展势头强劲,已成为我国重要的贸易新业态、新模式,也是全球经济增长的新动能、新引擎,在国内国际“双循环”经济发展中扮演着重要角色。然而,当前国际政治大环境的恶化、新冠疫情以及跨境电商自身发展缺陷等因素,都对我国国内国际经济“双循环”的进一步良性发展产生了影响。因此,应积极参与构建经济贸易全球化、完善跨境电商行业监管体系、“校政企行”多方参与专业人才培养、创新拉动内需,从而释放国内经济发展的潜力,提高我国经济在全球范围内的竞争力。

关键词：跨境电商 “双循环”经济贸易全球化行业监管体系 “校政企行”多方合作

Optimizing Photovoltaic Performance by Kinetic Quenching of Layered Heterojunctions

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Chinese Journal of Polymer Science 2022年第1期40卷 29-37页

作者： Li-Feng Xu Zhan-Wen Xu jia-ping lin Li-Quan Wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The mixing morphology control plays a crucial role in photovoltaic power generation,yet this specific effect on device performances remains ***,we employed computational approaches to delineate the photovoltaic properties of layered heterojunction polymer solar cells with tunable mixing ***-step quench and two-step quench strategies were proposed to adjust the mixing morphology by thermodynamic and kinetic *** computation for the one-step quench revealed that modulating interfacial widths and interfacial roughness could significantly promote the photovoltaic performance of layered heterojunction polymer solar *** two-step quench can provide a buffer at a lower temperature before the kinetic quenching,leading to the formation of small-length-scale islands connected to the interface and a further increase in photovoltaic *** discoveries are supported by recent experimental evidence and are anticipated to guide the design of photovoltaic materials with optimal performance.

关键词： Dissipative particle dynamics Drift-diffusion model Polymer solar cells Quench

Normal sperm head morphometric reference values in fertile Asian males

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Asian Journal of Andrology 2024年第3期26卷 315-320页

作者： Ye-lin jia Ying-Bi Wu lin Yu Yan Zheng Ting-Ting Yang Yan-Yun Wang Bin Zhou lin Zhang Fu-ping Li Laboratory of Andrology West China Second University Hospital Human Sperm BankChengdu 610000China Laboratory of Molecular Translational Medicine Center for Translational MedicineChengdu 610061China Key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University) Ministry of EducationChengdu 610061China NHC Key Laboratory of Chronobiology West China Second University HospitalSichuan UniversityChengdu 610000China

Sperm head morphology is crucial for male factor infertility diagnosis and assessment of male reproductive *** are available to analyze sperm head morphology,but they are limited by poor methodology comparability and *** study aimed to explore comprehensive and new normal morphometric reference values for spermatozoa heads infertile Asian *** automated sperm morphology analysis system captured 23152 stained spermatozoa from confirmed *** these samples,1856 sperm head images were annotated by three experienced laboratory technicians as“normal”.Weemployed 14 novel morphometric features to describe sperm head size(head length,head width,length/width ratio,and girth),shape(ellipse intersection over union,girth intersection over union,short-axis symmetry,and long-axis symmetry),area(head,acrosome,postacrosomal areas,and acrosome area ratio),and degrees of acrosome and nuclear *** straight-forwardmethod for the morphometric analysis of sperm by accurate visual measurements is clinically *** measured parameterspresent valuable information to establish morphometric reference intervals for normal sperm heads in fertile Asian *** detailed measurement data will be valuable for interlaboratory comparisons and technician *** vitro fertilizationand andrology laboratory technicians can use these parameters to perform objective morphology evaluation when assessing malefertilization potential.

关键词： fertile Asian males head morphometric reference value normal spermatozoa

Valence-tailored copper-based nanoparticles for enhanced chemodynamic therapy through prolonged ROS generation and potentiated GSH depletion

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Nano Research 2024年第7期17卷 6342-6352页

作者： Xinyang Li Binbin Ding Jing Li Di Han Hao Chen jia Tan Qi Meng Pan Zheng ping’an Ma Jun lin State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Chemodynamic therapy(CDT),an inventive approach to cancer treatment,exploits innate chemical processes to trigger cell death through the generation of reactive oxygen species(ROS).While offering advantages over conventional treatments,the optimization of CDT efficacy presents challenges stemming from suboptimal catalytic efficiency and the counteractive ROS scavenging effect of intracellular glutathione(GSH).In this study,we aim to address this dual challenge by delving into the role of copper valence states in *** the unique attributes of copper-based nanoparticles,especially zero-valent copper nanoparticles(CuPd NPs),we aim to enhance the therapeutic potential of *** experiments reveal that zero-valent CuPd NPs outperform divalent copper nanoparticles(Ox-CuPd NPs)by displaying superior catalytic performance and sustaining ROS generation through a dual approach integrating peroxidase-like(POD-like)activity and Cu+***,zero-valent NPs exhibit enhanced GSH depletion compared to their divalent counterparts,thereby intensifying CDT and inducing ferroptosis,ultimately resulting in high-efficiency tumor growth *** findings reveal the impact of valences on CDT,providing novel insights for the optimization and design of CDT agents.

关键词： CuPd nanoparticle ferroptosis chemodynamic therapy valance tailoring tumor therapy

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： He-xiang Wu jia Qu lin-zhi Wu Key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China School of Civil Engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

Grain refinement of 5A06 aluminum alloy welds caused by tungsten inert gas welding arc characteristics under Ar-He alternating gas supply conditions:a coupled method of water-cooled copper plate test/numerical simulation

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Journal of Iron and Steel Research(International) 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian Miao jia-xin lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Machine Learning Security Defense Algorithms Based on Metadata Correlation Features

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Computers, Materials & Continua 2024年第2期78卷 2391-2418页

作者： Ruchun jia jianwei Zhang Yi lin College of Computer Science Sichuan UniversityChengdu610065China

With the popularization of the Internet and the development of technology,cyber threats are increasing day by *** such as malware,hacking,and data breaches have had a serious impact on *** network security environment in the era of big data presents the characteristics of large amounts of data,high diversity,and high real-time *** security defense methods and tools have been unable to cope with the complex and changing network security *** paper proposes a machine-learning security defense algorithm based on metadata association *** control over unauthorized users through privacy,integrity,and *** user model is established and the mapping between the user model and the metadata of the data source is *** analyzing the user model and its corresponding mapping relationship,the query of the user model can be decomposed into the query of various heterogeneous data sources,and the integration of heterogeneous data sources based on the metadata association characteristics can be *** and classify customer information,automatically identify and perceive sensitive data,build a behavior audit and analysis platform,analyze user behavior trajectories,and complete the construction of a machine learning customer information security defense *** experimental results show that when the data volume is 5×103 bit,the data storage integrity of the proposed method is 92%.The data accuracy is 98%,and the success rate of data intrusion is only 2.6%.It can be concluded that the data storage method in this paper is safe,the data accuracy is always at a high level,and the data disaster recovery performance is *** method can effectively resist data intrusion and has high air traffic control *** can not only detect all viruses in user data storage,but also realize integrated virus processing,and further optimize the security defense effect of user big data.

关键词： Data-oriented architecture metadata correlation features machine learning security defense data source integration

Possible Role of Cellular Polyamine Metabolism in Neuronal Apoptosis

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Current Medical Science 2024年第2期44卷 281-290页

作者： Xin-tong JI Wen-lei YU Meng-jia JIN lin-jie LU Hong-ping YIN Huan-huan WANG School of Basic Medical Sciences Affiliated Hospital of Hangzhou Normal UniversityHangzhou Normal UniversityHangzhou 311121China School of Medicine Chongqing UniversityChongqing 400030China Department of Stomatology Huzhou Wuxing District People's HospitalHuzhou Wuxing District Maternal and Child Health HospitalHuzhou 313008China School of Pharmacy Zhejiang UniversityHangzhou 310030China Department of Stomatology Haining Hospital of Traditional Chinese MedicineJiaxing 314400China

Recent studies have shown that cellular levels of polyamines(PAs)are significantly altered in neurodegenerative *** from in vivo animal and in vitro cell experiments suggests that the cellular levels of various PAs may play important roles in the central nervous system through the regulation of oxidative stress,mitochondrial metabolism,cellular immunity,and ion channel *** of PA metabolism related enzymes also contributes to neuronal injury and cognitive impairment in many neurodegenerative ***,in the current work,evidence was collected to determine the possible associations between cellular levels of PAs,and related enzymes and the development of several neurodegenerative diseases,which could provide a new idea for the treatment of neurodegenerative diseases in the future.

关键词： polyamine apoptosis mitochondria neurodegenerative disease