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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 249-256页

作者： qing-yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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Sex-dependent alterations in extracellular vesicles linking chronic spinal cord injury to brain neuroinflammation and neurodegeneration

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Neural Regeneration Research 2025年第2期20卷 483-484页

作者： yun Li Junfang Wu Department of Anesthesiology&Shock Trauma and Anesthesiology Research(STAR)CenterUniversity of Maryland School of MedicineBaltimoreMDUSA

Traumatic spinal cord injury(SCI)is a devastating exogenous injury with long-lasting consequences and a leading cause of death and disability *** in assistive technology,rehabilitative interventions,and the ability to identify and intervene in secondary conditions have significantly increased the long-term survival rate of SCI patients,with some people even living well into their seventh or eighth *** survival changes have led neurotrauma researchers to examine how SCI interacts with brain *** health and epidemiological data showed that patients with long-term SCI can have a lower life expectancy and quality of life,along with a higher risk of comorbidities and complications.

关键词： alterations inflammation injury

Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang Yi-De Zhang Jie Chen Hai-di Fan Wan Wang Bin Wang Ju-yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian Guo Jian-Gang Shen Su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang qing Shi Guofan Zhang Yuxuan Zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

Physarum polycephalum-inspired adaptive optimization design of artificial microtubular networks

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Science China Chemistry 2025年

作者： Si-Min Zeng di-Wei Zheng Ting Pan Xing-Lan ding yun Zhang Chi-Hui Yang Si-Xue Cheng Xian-Zheng Zhang Key Laboratory of Biomedical Polymers of Ministry of Education&Department of Chemistry Wuhan University

Natural biological microtubular networks have undergone adaptive evolutionary selection and may offer viable solutions to design challenges in artificial microtubular networks. The plasmodium of the slime mold Physarum polycephalum(P. polycephalum) extends continuously to form a protoplasmic microtubular network structure, directly connecting food *** simulations revealed that the formation of this adaptive P. polycephalum microtubular network could be captured by a mathematical algorithm. Inspired by the P. polycephalum microtubular networks, we propose an adaptive optimization design method for artificial microtubular networks. Specifically, we utilized hydrogels with biodegradable and tissue-adhesive properties to replicate the P. polycephalum microtubular networks via photomask. In Rhodamine B diffusion and glucosecatalyzed reaction experiments, we found that the P. polycephalum microtubular networks exhibited significantly enhanced efficiency compared to vascular and artificial networks. Furthermore, we demonstrated the potential for uric acid(UA) degradation of the hydrogels with a real P. polycephalum microtubular network loaded with urate oxidase(UOx) in a rodent model of hyperuricemia. And this network achieved more than double the effect of the artificial network. This underscores the potential of natural microtubular networks to replace artificial microtubular networks.

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Domain generalization with semi-supervised learning for people-centric activity recognition

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Science China(Information Sciences) 2025年第1期68卷 171-188页

作者： Jing LIU Wei ZHU di LI Xing HU Liang SONG Academy for Engineering & Technology Fudan University Shanghai East-bund Research Institute on Networking Systems of AI School of Optoelectronic Information and Computer Engineering University of Shanghai for Science & Technology

People-centric activity recognition is one of the most critical technologies in a wide range of real-world applications,including intelligent transportation systems, healthcare services, and brain-computer interfaces. Large-scale data collection and annotation make the application of machine learning algorithms prohibitively expensive when adapting to new tasks. One way of circumventing this limitation is to train the model in a semi-supervised learning manner that utilizes a percentage of unlabeled data to reduce the labeling burden in prediction tasks. Despite their appeal, these models often assume that labeled and unlabeled data come from similar distributions, which leads to the domain shift problem caused by the presence of distribution gaps. To address these limitations, we propose herein a novel method for people-centric activity recognition,called domain generalization with semi-supervised learning(DGSSL), that effectively enhances the representation learning and domain alignment capabilities of a model. We first design a new autoregressive discriminator for adversarial training between unlabeled and labeled source domains, extracting domain-specific features to reduce the distribution gaps. Second, we introduce two reconstruction tasks to capture the task-specific features to avoid losing information related to representation learning while maintaining task-specific consistency. Finally, benefiting from the collaborative optimization of these two tasks, the model can accurately predict both the domain and category labels of the source domains for the classification task. We conduct extensive experiments on three real-world sensing datasets. The experimental results show that DGSSL surpasses the three state-of-the-art methods with better performance and generalization.

关键词： activity recognition deep learning domain generalization semi-supervised learning adversarial training

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A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi yun-Hao Xu Ming-Hui Chen Peng Zhao Wen-Bo Deng Ji Xiong Kai Guo Ya-qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

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IoT Empowered Early Warning of Transmission Line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： Zhe Li yun Liang Jinyu Wang Yang Gao State Grid Henan Electric Power Company Electric Power Scientific Research Institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism

Recent progress in constructing fluorinated solid-electrolyte interphases for stable lithium metal anodes

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 270-291页

作者： di Zhang Pengfei Lv Wei Qin Xin He Yuanhua He Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province College of Civil Aviation Safety EngineeringCivil Aviation Flight University of ChinaGuanghan 618307China School of Chemical Engineering Sichuan UniversityChengdu 610065China

Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.

关键词： LiF lithium metal anodes solid-electrolyte interphase interface cycling stability