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Chinese Journal of Polymer Science 2024年第5期42卷 591-603,I0006页

作者： Qiong-Jun Xu Zhao-Yang Yuan Chang-Cheng Wang Hao liang Yu shi Hai-Tao wu Hu Xu Jing Zheng Jin-Rong wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China

Semi-interpenetrating(semi-IPN)hydrogels formed by the continuous interpenetration of cross-linked polymer network and linear non-crosslinked polymer with multifunctionality are widely used in biomedical and other ***,the negative impact of linear polymer on the homogeneity of the cross-linked network often leads to a decrease in the mechanical properties of semi-IPN hydrogels and severely limits their ***,a bioinspired hydrogen-bonding induced phase separation strategy is presented to construct the tough semi-IPN polyvinylpyrrolidone/polyacrylamide hydrogels(named PVP/PAM hydrogels),including the linear polymer polyvinylpyrrolidone(PVP)and cross-linked polyacrylamide(PAM)*** resultant PVPx/PAM hydrogels exhibit unique phase separation induced by the hydrogen bonding between PVP and PAM and affected by the amount of substance of ***,the phase separation of PVPx/PAM hydrogels results in excellent mechanical properties with a strain of 2590%,tensile strength of 0.28 MPa and toughness of 2.17 MJ/m^(3).More importantly,the hydrogen bonding between PVP and PAM firstly disrupts to dissipate energy under external forces,so the PVPx/PAM hydrogels exhibit good self-recovery properties and outperform chemically cross-linked PAM hydrogels in impact resistance and damping *** is believed that the PVPx/PAM hydrogels with hydrogen-bonding induced phase separation possess more potential application prospects.

关键词： Tough Semi-interpenetrating networks Polyvinylpyrrolidone/polyacrylamide Hydrogels Phase separation

A potential threat from biodegradable microplastics: mechanism of cadmium adsorption and desorption in the simulated gastrointestinal environment

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 63-75页

作者： Timing Jiang Xiang wu Shushan Yuan Changfei Lai shijie Bian Wenbo Yu Sha liang Jingping Hu liang Huang Huabo Duan Yafei shi Jiakuan Yang School of Environmental Science&Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Resources and Environmental Science Hubei UniversityWuhan 430062China Hubei Provincial Engineering Laboratory for Solid Waste Treatment Disposal and Recycling Wuhan 430074China School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan 430068China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China

It has been demonstrated that microplastics (MPs) can accumulate heavy metals from the environment and transfer them into organisms via the food chain. However, adsorption and desorption capacities for biodegradable MPs relative to those for conventional MPs remain poorly understood. In this study, cadmium (Cd(II)) adsorption and desorption characteristics of polylactic acid (PLA), a typical biodegradable MP, were investigated. Two conventional MPs, i.e., polypropylene (PP) and polyamide (PA) were used for comparison. The maximum Cd(II) adsorption capacities of the MPs studied in the adsorption experiments decreased in the order PA (0.96 ± 0.07 mg/g) > PLA (0.64 ± 0.04 mg/g) > PP (0.22 ± 0.03 mg/g). The Pseudo-second-order kinetic model and Freundlich isothermal model described the Cd(II) adsorption behaviors of PLA MPs well. X-ray photoelectron spectroscopy and two-dimensional Fourier transform infrared correlation spectroscopy analysis indicated that oxygen functional groups were the major and preferential binding sites of PLA MPs, which contributed to their high Cd(II) adsorption capacities. Simulated gastric and intestinal fluids both significantly enhanced the desorption capacities of the examined MPs. Notably, degradation of the PLA MPs during in vitro human digestion made the Cd(II) on the PLA MPs more bioaccessible (19% in the gastric phase and 62% in the intestinal phase) than Cd(II) on the PP and PA MPs. These results indicate the remarkable capacities of biodegradable MPs to accumulate Cd(II) and transfer it to the digestive system and show that biodegradable MPs might pose more severe threats to human health than conventional nonbiodegradable MPs.

关键词： Biodegradable microplastics Cadmium Adsorption and desorption Gastrointestinal environment Two-dimensional correlation spectroscopy Bioaccessibility

Research on Credit Default Swaps Pricing Considering Moral Hazard Incentive under Reduce-Form Model

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 311-329页

作者： liang wu Kangjie He Zhe Guo School of Mathematical Science Henan Institute of Science and TechnologyXinxiang453003China Public Front Office Department Industrial and Commercial Bank of ChinaZhengzhou450000China

Equilibrium pricing of credit default swaps(CDS)promotes efficient identification of credit risk in the market,which in turn leads to efficient allocation of ***,even when CDS have been priced in equilibrium,i.e.,when premiums are equal to anticipated payments,the moral hazard incentives of CDS buyers increase with CDS ***,it becomes an interesting research direction to study the impact of moral hazard incentives on the trading mechanism or pricing of derivatives(CDS).Most of the existing literature on the impact of moral hazard incentives in CDS pricing on derivatives trading mechanisms takes a macro perspective and focuses on the agreement risk *** literature exploring the analysis of the impact of moral hazard on the probability of agreement default from a micro perspective is not yet *** this in mind,this paper focuses on the mechanisms by which“fraud”,an extreme manifestation of micro-moral hazard incentives,affects the probability of *** paper introduces for the first time the concept of“claiming fraud”by credit protection buyers,which is different from the macro perspective of moral hazard incentives,and thus defines a specific extreme form of moral hazard ***,to address the intrinsic feature of the lack of economic explanatory power of the reduce-form model,this paper introduces a moral hazard incentive factor into the reduce-form model,and proposes a moral hazard state variable as a function of the asset value of the reference entity,which gives the reduce-form model strong economic explanatory power,and the default predictability is reduced by the description of the reduce-form *** terms of the object of study,this paper considers the issue of moral hazard incentives in the presence of claiming fraud in two reference entities to further explore the impact of moral hazard incentives on default protection at the micro level in terms of cyclic ***,based on the

关键词： Financial engineering moral hazard incentive claiming fraud reduce-form model probability of default calculation CDS pricing

Genesis of the Nuri Cu-W-Mo Deposit,Tibet,China:Constraints from in situ Trace Elements and Sr Isotopic Analysis of Scheelite

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 117-131页

作者： WANG Yiyun wu Zhishan CHEN Wenqing DU Qing’an TANG Liwei shi Hongzhao MA Guotao ZHANG Zhi liang Wei wu Bo MIAO Hengyi Chengdu Center China Geological Survey(Geoscience Innovation Center of Southwest China)Chengdu 610081China The Second Geological Institute of China’s Metallurgical Geology Bureau Fuzhou 351111China

The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,***,the genetic type of this deposit has been controversial since its *** on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,*** LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are *** Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth *** contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and *** normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock *** the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric *** intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a

关键词： trace elements in situ Sr isotopes tungsten mineralization Gangdese metallogenic belt Tibet

Correction of a CADASIL point mutation using adenine base editors in hiPsCsandbloodvessel organoids

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Journal of Genetics and Genomics 2024年第2期51卷 197-207页

作者： Jingwen Wang Lei Zhang Guanglan wu Jinni wu Xinyao Zhou Xiaolin Chen Yongxia Niu Yiren Jiao Qianyi Liu Puping liang Guang shi Xueqing wu Junjiu Huang MOE Key Laboratory of Gene Function and Regulation State Key Laboratory of BiocontrolSchool of Life SciencesSun Yat-sen UniversityGuangzhouGuangdong 510275China Key Laboratory of Reproductive Medicine of Guangdong Province The First Affiliated Hospital and School of Life SciencesSun Yat-sen UniversityGuangzhouGuangdong 510275China Center of Reproductive Medicine Children's Hospital of Shanxi and Women Health Center of ShanxiTaiyuanShanxi 030013China

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a monogenic small vessel disease caused by mutations in the NOTCH3 gene. However, the pathogenesis of CADASIL remains unclear, and patients have limited treatment options. Here, we use human induced pluripotent stem cells (hiPSCs) generated from the peripheral blood mononuclear cells of a patient with CADASIL carrying a heterozygous NOTCH3 mutation (c.1261C>T, p.R421C) to develop a disease model. The correction efficiency of different adenine base editors (ABEs) is tested using the HEK293T-NOTCH3 reporter cell line. ABEmax is selected based on its higher efficiency and minimization of predicted off-target effects. Vascular smooth muscle cells (VSMCs) differentiated from CADASIL hiPSCs show NOTCH3 deposition and abnormal actin cytoskeleton structure, and the abnormalities are recovered in corrected hiPSC-derived VSMCs. Furthermore, CADASIL blood vessel organoids generated for in vivo modeling show altered expression of genes related to disease phenotypes, including the downregulation of cell adhesion, extracellular matrix organization, and vessel development. The dual adeno-associated virus (AAV) split-ABEmax system is applied to the genome editing of vascular organoids with an average editing efficiency of 8.82%. Collectively, we present potential genetic therapeutic strategies for patients with CADASIL using blood vessel organoids and the dual AAV split-ABEmax system.

关键词： CADASIL Induced pluripotent stem cells Adenine base editors AAV Blood vessel Organoid

Resource allocation for D2D-assisted haptic communications

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Digital Communications and Networks 2024年第1期10卷 63-74页

作者： Yan wu Chao Yue Yang Yang liang Ao College of Telecommunication Engineering Army Engineering University of PLANanjing210000China

Haptic communications is recognized as a promising enabler of extensive services by enabling real-time haptic control and feedback in remote environments,e.g.,teleoperation and autonomous *** the strict transmission requirements on reliability and latency,Device-to-Device(D2D)communications is introduced to assist haptic *** particular,the teleoperators with poor channel quality are assisted by auxiliaries,and each auxiliary and its corresponding teleoperator constitute a D2D ***,the haptic interaction and the scarcity of radio resources pose severe challenges to the resource allocation,especially facing the sporadic packet ***,the contentionbased access scheme is applied to achieve low-latency transmission,where the resource scheduling latency is omitted and users can directly access available *** this context,we derive the reliability index of D2D pairs under the contention-based access scheme,i.e.,closed-loop packet error ***,the reliability performance is guaranteed by bidirectional power control,which aims to minimize the sum packet error probability of all D2D *** game theory is introduced to solve the problem with low ***,a distributed power control algorithm based on synchronous log-linear learning is proposed to converge to the optimal Nash *** results demonstrate the superiority of the proposed learning algorithm.

关键词： Haptic communications D2D Power control Contention-based access Potential game

Recent progress in MOFs-based nanozymes for biosensing

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Nano Research 2024年第1期17卷 39-64页

作者： Imamdin Chandio Yongjian Ai Lei wu Qionglin liang MOE Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryLaboratory of Flexible Electronics TechnologyCenter for Synthetic and Systems BiologyTsinghua University-Peking University Joint Centre for Life SciencesTsinghua UniversityBeijing 100084China

Nanozymes are nanomaterials with enzyme-mimicking catalytic *** to natural enzymes,nanozymes show various properties such as easy to manufacture,stable,adjustable,and *** play key roles in biosensing,biocatalysis,and disease *** an important kind of nanozymes,metal-organic framework(MOF)-based nanozymes are receiving a lot of attention due to their structural properties and *** developing MOF with enzymes-like catalytic properties has opened new perspectives in *** review summarizes the up-to-date developments in synthesizing two-dimensional and three-dimensional MOF-based nanozymes and their applications in ***,classification of nanozymes obtained by MOFs is categorized,and different properties of MOF-based nanozymes are ***,the distinctive applications of MOF-based nanozymes in identifying various analytes are thoroughly ***,the recent challenges and progressive directions in this area are highlighted.

关键词： metal-organic frameworks nanozymes metal-organic framework (MOF)-based nanozymes biosensing analytes

Screening of transition metal oxides for electrocatalytic nitrate reduction to ammonia at large currents

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Nano Research 2024年第5期17卷 3902-3910页

作者： Qiongfei wu Weijie Zhu Dongxu Ma Chao liang Zhoucheng Wang Hanfeng liang State Key Laboratory of Physical Chemistry of Solid Surfaces Tan Kah Kee Innovation LaboratoryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China College of Chemical Engineering Tianjin UniversityTianjin 300072China

Electrochemical nitrate reduction reaction(NO_(3)RR)towards ammonia,as an emerging and appealing technology alternative to the energy-intensive Haber-Bosch process and inefficient nitrogen reduction reaction,has recently aroused wide concern and ***,the current research of the NO_(3)RR towards ammonia lacks the overall performance comparison of various *** this,we here make a comparison of 12 common transition metal oxide catalysts for the NO_(3)RR under a high cathodic current density of 0.25 A·cm^(-2),wherein Co_(3)O_(4) catalyst displays the highest ammonia Faradaic efficiency(85.15%)and moderate activity(ca.-0.25 V *** hydrogen electrode).Other external factors,such as nitrate concentrations in the electrolyte and applied potential ranges,have also been specifically investigated for the NO_(3)RR.

关键词： nitrate reduction reaction ammonia production transition metal oxides Co_(3)O_(4)

Linear Viscoelasticity of ABA-type Vitrimer Based on Dioxaborolane Metathesis

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Chinese Journal of Polymer Science 2024年第10期42卷 1495-1504页

作者： shi-Long wu Huan-Huan Yang Quan Chen State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Science University of Science and Technology of China

In this study, we synthesized a series of ABA-type vitrimers by crosslinking the short A moieties of precursors with a bifunctional crosslinker and evaporating the small molecular byproduct. The vitrimer samples thus prepared exhibit linear viscoelasticity dependent on the length of A moiety as well as the content of the crosslinks. When the average number of A monomers per end moiety m=1.1, the crosslinker can only extend the chain but not crosslink the chain. When m becomes 2.8 or higher, introducing a crosslinker first leads to the gelation, whereas excess in crosslinker molecules leads opening of the crosslinking sites and accordingly reentry into the sol regime. Surprisingly, a further increase in the length of the A moieties increases the relaxation time much weaker than the exponential increase seen for the physically crosslinked ABAtype ionomers. We attribute this difference to the distinct relaxation mechanisms:the relaxation of the vitrimer samples is based on relatively independent exchange reactions, which contrasts with the ABA-type ionomers that relax through the collective hopping of connected ionic groups from one ion aggregate to another.

关键词： ABA-type vitrimer Kinetics and thermodynamics Linear viscoelasticity Polymer rheology Relaxation mechanism

Loyal wingman task execution for future aerial combat:A hierarchical prior-based reinforcement learning approach

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Chinese Journal of Aeronautics 2024年第5期37卷 462-481页

作者： Jiandong ZHANG Dinghan WANG Qiming YANG Zhuoyong shi Longmeng JI Guoqing shi Yong wu School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China

In modern Beyond-Visual-Range(BVR)aerial combat,unmanned loyal wingmen are pivotal,yet their autonomous capabilities are *** study introduces an advanced control algorithm based on hierarchical reinforcement learning to enhance these capabilities for critical missions like target search,positioning,and relay *** on a dual-layer model,the algorithm’s lower layer manages basic aircraft maneuvers for optimal flight,while the upper layer processes battlefield dynamics,issuing precise navigational *** approach enables accurate navigation and effective reconnaissance for lead ***,our Hierarchical Prior-augmented Proximal Policy Optimization(HPE-PPO)algorithm employs a prior-based training,prior-free execution method,accelerating target positioning training and ensuring robust target *** paper also improves missile relay guidance and promotes the effective *** integrating this system with a human-piloted lead aircraft,this paper proposes a potent solution for cooperative aerial *** experiments demonstrate enhanced survivability and efficiency of loyal wingmen,marking a significant contribution to Unmanned Aerial Vehicles(UAV)formation control *** advancement is poised to drive substantial interest and progress in the related technological fields.

关键词： Beyond-visual-range Loyal wingmen Hierarchical prior-augmented proximal policy optimization Unmanned aerial vehicles Warfare