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Synthesis and Self-assembly of a Linear Coil-Coil-Rod ABC Triblock Copolymer

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Chinese Journal of Polymer Science 2014年第11期32卷 1524-1534页

作者： Ling-ying Shi Yu Pan qi-kai zhang Yu Zhou Xing-he Fan 沈志豪 Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

An interesting order-order transition between two different complex nanostructures was observed in a new liquid crystalline linear coil-coil-rod ABC triblock copolymer（tri BCP）. First, the ABC tri BCP, poly（dimethylsiloxane）-bpolystyrene-b-poly{2,5-bis[（4-methoxyphenyl）oxycarbonyl]styrene}（PDMS-b-PS-b-PMPCS）, was synthesized through sequential atom transfer radical polymerization. The degrees of polymerization of PDMS, PS, and PMPCS blocks are 58, 159, and 106, and the corresponding volume fractions of PDMS, PS, and PMPCS are 0.09, 0.29, and 0.62, respectively. The phase behaviors of the PDMS-b-PS diblock copolymer precursor and the final triblock copolymer were studied by smallangle X-ray scattering, one-dimensional wide-angle X-ray scattering, and transmission electron microscopy experiments. The PDMS-b-PS precursor self-assembles into hexagonally packed cylinders with a relatively small periodic size after thermal annealing. When the triblock copolymer is annealed at a relatively low temperature（120 ○C） at which the PMPCS block is in the amorphous state, the tri BCP forms core-shell hexagonally packed cylinders（CSH） with a relativly large periodic size. After the tri BCP is annealed above 140 ○C at which the PMPCS block transforms to the liquid crystalline（LC） phase, the nanophase-separated structure transforms to a three-phase four-layer lamellar structure（LAM-3P4L）. Thus, accompanied with the transition of the PMPCS blocks from the amorphous state to the LC phase, the order-order transition from CSH to LAM-3P4 L occurs in the PDMS-b-PS-b-PMPCS ABC tri BCP.

关键词： Coil-coil-rod triblock copolymer Self-assembly Order-order transition Liquid crystalline polymer Complex nanostructures.

GAM:A GPU-Accelerated Algorithm for MaxRS Queries in Road Networks

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Journal of Computer Science & Technology 2022年第5期37卷 1005-1025页

作者： Jian Chen kai-qi zhang Tian Ren Zhen-qing Wu Hong Gao School of Computer Science and Technology Harbin Institute of TechnologyHarbin150001China

In smart phones,vehicles and wearable devices,GPS sensors are ubiquitous and collect a lot of valuable spatial data from the real *** a set of weighted points and a rectangle r in the space,a maximizing range sum(MaxRS)query is to find the position of r,so as to maximize the total weight of the points covered by r(i.e.,the range sum).It has a wide spectrum of applications in spatial crowdsourcing,facility location and traffic *** of the existing research focuses on the Euclidean space;however,in real life,the user’s moving route is constrained by the road network,and the existing MaxRS query algorithms in the road network are *** this paper,we propose a novel GPU-accelerated algorithm,namely,GAM,to tackle MaxRS queries in road networks in two phases *** phase 1,we partition the entire road network into many small cells by a grid and theoretically prove the correctness of parallel query results by grid shifting,and then we propose an effective multi-grained pruning technique,by which the majority of cells can be pruned without further *** phase 2,we design a GPU-friendly storage structure,cell-based road network(CRN),and a two-level parallel framework to compute the final result in the remaining ***,we conduct extensive experiments on two real-world road networks,and the experimental results demonstrate that GAM is on average one order faster than state-of-the-art competitors,and the maximum speedup can achieve about 55 times.

关键词： road network maximizing range sum GPU acceleration pruning strategy

Implementation of a cusp-like for real-time digital pulse shaper in nuclear spectrometry

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Nuclear Science and Techniques 2017年第7期28卷 79-84页

作者： Jun Liu Jian Yang Guo-qiang Zeng kai-qi zhang Shi-Long Wei Liang-Quan Ge Chengdu University of Technology Chengdu 610059 China

Pulse shaping,which improves signal-to-noise ratio excellently,has been extensively used in nuclear signal *** paper presents a cusp-like pulse-shaping technique developed through the recursive difference equation in time *** can be implemented in field programmable gate array hardware *** flat-topped cusp-like shaper is developed to optimize the time constant of pulse shaping and reduce the influence of ballistic *** methods of both baseline restoration and pile-up rejection are *** ^(137)Cs energy spectra measured with the digital cusp-like shaper are 6.6% energy resolution,while those by traditional analog pulse shaper are 7.2% energy resolution,under the same *** technique offers flexibility,too,in adjusting the pulse shaper parameters.

关键词：脉冲整形器现场可编程门阵列能量分辨率尖点实时谱仪递归差分方程整形技术

Secondary Structurc in Solution of an Analog of Salmon Calcitonin:[Val^1, Ala^7]sCT

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Chinese Chemical Letters 1999年第7期10卷 555-558页

作者： Bin YANG Hou Li JIANG Zhen kai DING qi kai zhang(Beijing Institute of Pharmacology and Toxicology Beijing 100850National Center of Biomedical Analysis. Beijing 100850) Beijing Inst. Pharmacol. Toxicol. Beijing 100850 China Natl. Center of Biomedical Analysis Beijing 100850 China

Secondary structure of [Val. Ala]sCT- an analog of salmon calcitonin (sCT) not containing an N-terminal disultide bridge. was investigated by circular dichroism (CD) and Fourier-transform intrared spectroscopy (FTIR) methods. Both CD and FTIR results show that the main contbrmational structure of [Val Ala']sCT in aqueous solution is random coil structure. while in trifluorethanol (TFE) it displays a strong α-helical structure. The relationship between the biological activity and the conformational structure of [Val, Ala] sCT is als0 discussed.

关键词： Salmon calcitonin analog CD FTIR peptide secondary structure

A novel approach to predict green density by high-velocity compaction based on the materials informatics method

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 194-201页

作者： kai-qi zhang Hai-qing Yin Xue Jiang Xiu-qin Liu Fei He Zheng-hua Deng Dil Faraz Khan qing-jun Zheng Xuan-hui Qu Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Beijing Key Laboratory of Materials Genome Engineering Beijing Laboratory of Metallic Materials and Processing for Modern Transportation School of Mathematics and Physics University of Science and Technology Beijing Chongqing Engineering Technology Research Center for Light Alloy and Processing Department of Physics University of Science and Technology Bannu Kennametal Inc

High-velocity compaction is an advanced compaction technique to obtain high-density compacts at a compaction velocity of ≤10 m/s. It was applied to various metallic powders and was verified to achieve a density greater than 7.5 g/cm^3 for the Fe-based powders. The ability to rapidly and accurately predict the green density of compacts is important, especially as an alternative to costly and time-consuming materials design by trial and error. In this paper, we propose a machine-learning approach based on materials informatics to predict the green density of compacts using relevant material descriptors, including chemical composition, powder properties, and compaction energy. We investigated four models using an experimental dataset for appropriate model selection and found the multilayer perceptron model worked well, providing distinguished prediction performance, with a high correlation coefficient and low error values. Applying this model, we predicted the green density of nine materials on the basis of specific processing parameters. The predicted green density agreed very well with the experimental results for each material, with an inaccuracy less than 2%. The prediction accuracy of the developed method was thus confirmed by comparison with experimental results.

关键词： powder metallurgy high-velocity compaction green density data mining multilayer perceptron

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang Bing zhang Lanfang Li Xiaomei Tang Jinyu Zeng Yige Song Chao Xu kai Zhao Guoqiang Liu Youming Lu Xinyan Li kai Shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

Therapeutic effect of transcatheter arterial chemoembolization and percutaneous injection of acetic acids on primary liver cancer

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Hepatobiliary & Pancreatic Diseases International 2004年第1期3卷 55-57页

作者： Hong-Bin Chen, Yue Huang, Dong-Ling Dai, Xia zhang, Zhong-Wen Huang, qi-kai zhang, Hui-Hua Wang, Jun-Su zhang and Ge Pan Sanming, China Departments of Gastroenterology , Interventional Therapy , Ultrasonography and CT , Sanming Municipal First Hospital, Sanming 365000, China Department of Gastroenterology, Second Affiliated Hospital, Chongqing Medical University, Chongqing 400000, China Department of Gastroenterology Sanming Municipal First Hospital Sanming 365000 China. smchb@***

BACKGROUND: The resection rate of primary liver tumor in China is only about 20%. A lot of patients with moderate and advanced liver tumor may lose the chance of opera- tion. The objective of present research was to study the ef- ficacy of transcatheter arterial chemoembolization (TACE) combined with percutaneous injection of chemical agents and acetic acids in the treatment of patients with primary liver cancer (PLC). METHODS: Thirty-three patients with middle and ad- vanced stage of PLC were divided into two groups: percu- taneous injection of chemical agents and acetic acids (15 patients, group A) and TACE (18 patients, group B). RESULTS: Tumor diameter and serum AFP level reduced to 86.6% and 83.3% in group A, and 55.5% and 40% in group B, respectively. There was significant difference be- tween the two groups ( P < 0 . 0 1 ) . The 1-, 2-, 3-, 4-year survival rates of group A were 96.7%, 86.6%, 51.3%, 33.3%, respectively and in group B were 66.7%, 44.4%, 16.7%, 0%, respectively (P<0.01). CONCLUSION: TACE combined with percutaneous injec- tion of chemical agents and acetic acids is efficacious to in- crease the survival rate of patients with PLC.

关键词： primary liver cancer liver artery chemoembolization chemical drug injection acetic acid

Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury

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Neural Regeneration Research 2025年第10期20卷 2807-2822页

作者： Xizi Song Ruixin Li Xiaolei Chu qi Li Ruihua Li qingwen Li kai-Yu Tong Xiaosong Gu Dong Ming Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Haihe Laboratory of Brain-Machine Interface and Human-Machine Fusion TianjinChina Department of Rehabilitation Tianjin University Tianjin HospitalTianjinChina Department of Hand Microsurgery Tianjin University Tianjin HospitalTianjinChina School of Exercise and Health Tianjin University of SportTianjinChina Department of Biomedical Engineering the Chinese University of Hong KongHong Kong Special Administrative RegionChina

Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and *** on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target *** has led to restrictions on current therapeutic *** this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target *** peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal *** nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury *** damage to target organs can occur,including skeletal muscle atrophy and sensory receptor *** then provide a brief review of the research advances in therapeutic approaches to peripheral nerve *** main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical ***,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ ***,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.

关键词： central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach

Lipid droplets in the nervous system:involvement in cell metabolic homeostasis

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Neural Regeneration Research 2025年第3期20卷 740-750页

作者： Yuchen zhang Yiqing Chen Cheng Zhuang Jingxuan qi Robert Chunhua Zhao Jiao Wang School of Life Sciences Shanghai UniversityShanghaiChina School of Medicine Shanghai UniversityShanghaiChina Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic MedicinePeking Union Medical CollegeBeijingChina Center of Excellence in Tissue Engineering Chinese Academy of Medical SciencesBeijingChina Beijing Key Laboratory of New Drug Development and Clinical Trial of Stem Cell Therapy BeijingChina

Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous *** droplet formation begins with the synthesis of neutral lipids in the endoplasmic ***,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous *** addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress ***,lipid droplets exhibit specific functions in neurons and glial *** of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system *** review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and ***,it will explore the association between lipid droplets and neurodegenerative *** the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

关键词： Alzheimer's disease lipid droplet biogenesis lipid droplets lipid metabolism nervous system neurodegenerative disorders oxidative stress Parkinson's disease