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Phenotypic changes of Schwann cells on the proximal stump of injured peripheral nerve during repair using small gap conduit tube

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Neural Regeneration Research 2017年第9期12卷 1538-1543页

作者： Shi-jun Zhang Wen-liang Wu Kai-yun Yang Yun-zhen Chen hai-chun liu Department of Orthopedics Qilu Hospital of Shandong University Laboratory of Ears Nose and Throat Oral and Maxillofacial Surgery Qilu Hospital of Shandong University

Dedifferentiation of Schwann cells is an important feature of the response to peripheral nerve injury and specific negative myelination reg- ulators are considered to have a major role in this process. However, most experiments have focused on the distal nerve stump, where the Notch signaling pathway is strongly associated with Schwann cell dedifferentiation and repair of the nerve. We observed the phenotypic changes of Schwann cells and changes of active Notch signaling on the proximal stump during peripheral nerve repair using small gap conduit tubulization. Eighty rats, with right sciatic nerve section of 4 mm, were randomly assigned to conduit bridging group and control group （epineurium suture）. Glial fibrillary acidic protein expression, in myelinating Schwann cells on the proximal stump, began to up-reg- ulate at 1 day after injury and was still evident at 5 days. Compared with the control group, Notchl mRNA was expressed at a higher level in the conduit bridging group during the first week on the proximal stump. Hesl mRNA levels in the conduit bridging group significantly increased compared with the control group at 3, 5, 7 and 14 days post-surgery. The change of the Notch intracellular domain shared a simi- lar trend as Hesl mRNA expression. Our results confirmed that phenotypic changes of Schwann cells occurred in the proximal stump. The differences in these changes between the conduit tubulization and epineurium suture groups correlate with changes in Notch signaling. This suggests that active Notch signaling might be a key mechanism during the early stage of neural regeneration in the proximal nerve stump.

关键词： nerve regeneration Schwann cells nerve injury small gap conduit therapy chitin peripheral nerve injury Notch signaling Notch 1 Hes1 glial fibrillary acidic protein S100 neural regeneration

Design,synthesis and biological evaluation of indole derivatives as novel inhibitors targeting B-Raf kinase

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Chinese Chemical Letters 2014年第2期25卷 351-354页

作者： Zeng Wu Ming Yan Shi-He Hu Zhi-Cheng Yu Yong Zhu Ya-Dong Cheng hai-chun liu Yan-Min Zhang Si-Hui Yao Wei-Fang Tang Tao Lu Department of Organic Chemistry China Pharmaceutical University National Nanjing Center for Drug Screening China Pharmaceutical University Laboratory of Molecular Design and Drug Discovery School of SciencesChina Pharmaceutical University State Key laboratory of Natural Medicines China Pharmaceutical University The Headmaster's Office China Pharmaceutical University

A series of novel indole derivatives were designed and synthesized and their inhibitory activity against B-Raf and HepG2 cell were also described. Among them, compounds 7a and 7b exhibited excellent potency, which sho... 详细信息

关键词： B-Raf kinase inhibitors Receptor-based drug discovery Indole derivatives Biological evaluation

Potential dependence in electrocatalysis: a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu liu Zhaoming Xia Zeyu Wang Yinjuan Chen hai Xiao Department of Chemistry Tsinghua University Fundamental Science Center of Rare Earths Ganjiang Innovation Academy Chinese Academy of Sciences Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation Center Changzhou University

Electrocatalysis is a key technology for the new energy era and sustainable development, serving as the interface for interconversion of electrical and chemical energies, which spans a wide spectrum of applications in sustainable energy and environmental engineering. Electrocatalytic reactions including electrochemical CO2reduction reaction （eCO2RR）, hydrogen evolution reaction （HER）, and oxygen evolution/reduction reactions （OER/ORR）, hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

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微博网络中用户主题兴趣相关性及主题信息扩散研究

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电子科技大学学报 2017年第2期46卷 458-468页

作者：罗春海刘红丽胡海波华东理工大学商学院上海徐汇区200237

运用Twitter-LDA主题模型对新浪微博数据进行了主题分析,基于用户主题兴趣相关性的研究表明用户间的主题兴趣具有三度相关性,同一主题兴趣下三度以内粉丝的发文数随用户发文数增加而波动式增加,各度粉丝与用户主题兴趣的相似度随粉丝度... 详细信息

运用Twitter-LDA主题模型对新浪微博数据进行了主题分析,基于用户主题兴趣相关性的研究表明用户间的主题兴趣具有三度相关性,同一主题兴趣下三度以内粉丝的发文数随用户发文数增加而波动式增加,各度粉丝与用户主题兴趣的相似度随粉丝度数的增加而下降。通过分析比较不同主题类别微博的扩散差异,发现生活情感类的信息最受用户欢迎,不同主题类别微博被转发的概率存在显著差异,平均转发数相差可达10倍,微博信息扩散树中各类主题在微博信息扩散深度、扩散时间间隔和用户的扩散能力方面都表现出不同的特征。

关键词：信息扩散微博网络主题分析用户行为

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

Propagating subduction initiation of the Caroline Plate at the Mussau Trench

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Science China Earth Sciences 2025年第1期68卷 253-269页

作者： chun-Feng LI Yongkang DENG Tao WU Dongdong DONG Guoliang ZHANG Jiazheng ZHANG Yutao liu Yaqing LI Fugui TANG Lulu ZHANG Department of Marine Sciences Zhejiang University Laboratory of Marine Mineral Resources Laoshan Laboratory Key Lab of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Key Lab of Ocean and Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Science & Technology on Integrated Information System Lab Institute of Software Chinese Academy of Sciences

New seismic imaging from the Mussau Trench confirms that, under horizontal compression on an oceanic plate boundary, it is within the young and weak oceanic plate that a trench will develop, and it is the young plate, not so long after its birth, that starts to subduct toward the old plate. The Mesozoic Pacific Plate cannot easily bend, under the joint horizontal compression and vertical gravity pull, even with a pre-existing weak zone in place and with a large age offset across the plate boundary. The bending of the Caroline Plate near the northern end of the Mussau Trench started only after a long-time span of trench migration, and/or after a prolonged transition from initial compression to trench development. Highly contrasting trench deformation and sedimentary accretion between two parallel seismic sections support an evident migration of underthrusting or significant longitudinal heterogeneity along the trench. The swift transition from underthrusting to non-thrusting can be explained by a counter-clockwise rotation of the Caroline Plate. That miniature accretionary wedges develop even before the subduction initiates imply strong compression and uplifting before the underthrusting can kick-start. Rotation of the Caroline Plate have been halted as the Mussau Trench is seismically rather quiet and the Lyra Trough to the east shows relaxational extension.

关键词： Mussau Trench Subduction initiation Seismic reflection Caroline Plate

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Structure and corrosion resistance of modified micro-arc oxidation coating on AZ31B magnesium alloy

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Transactions of Nonferrous Metals Society of China 2016年第3期26卷 814-821页

作者：崔学军杨瑞嵩刘春海余祖孝林修洲四川理工学院材料科学与工程学院自贡643000 四川理工学院材料腐蚀与防护四川省重点实验室自贡643000

A hydrophobic surface was fabricated on a micro-arc oxidation (MAO) treated AZ31 Mg alloys via surface modification with myristic acid. The effects of modification time on the wettability of the coatings were investigated using the contact angle measuring device. The surface morphologies and structure of the coatings were evaluated using SEM, XRD and FT-IR. The corrosion resistance was investigated by potentiodynamic polarization curves and long-term immersion test. The results showed that the water contact angle (CA) increases gradually with modification time from 0 to 5 h, the highest CA reaches 138° after being modified for 5 h, and the number and size of the micro pores are decreased. The modification method hardly alters crystalline structure of the MAO coating, but improves the corrosion resistance based on the much positive potential and low current density. Moreover, the corrosion resistance and hydrophobicity can be enhanced with increasing the alkyl chain. The wetting and spreading for the alkylcarboxylate with low surface energy become easier on the micro-porous surface, and alkylcarboxylate monolayer will be formed through bidentate bonding, which changes the surface micropores to a sealing or semi-sealing structure and makes the MAO coating dense and hydrophobic. All the results demonstrate that the modification process improves the corrosion protection ability of the MAO coating on AZ31B Mg alloy.

关键词： magnesium alloys micro-arc oxidation plasma electrolytic oxidation hydrophobicity myristic acid corrosion resistance

Effects of water level variations on the water quality of Huayang Lakes, China

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Journal of Geographical Sciences 2025年第1期35卷 173-188页

作者： AN Lesheng liu chun FAN Zhongya LIAO Kaihua WANG Wencai WANG Nan School of Resources and Environment Anqing Normal University South China Institute of Environmental Sciences Ministry of Ecology and Environment The Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyCAS

To explore water level variations and their dynamic influence on the water quality of Huayang Lakes, the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend test, box plots, and violin plots. The results show a notable hydrological rhythm of water level alternation between dry and flood seasons in Huayang Lakes, with an average water level of 12.82 m and a monthly range of 11.21–17.24m. Since 2017, the water level of Huayang Rivers has shown a decreasing trend of –0.02 m/*** phosphorus(TP) has become the primary pollutant. The TP concentrations in Longgan Lake(the largest lake) during the dry, rising, flood, and retreating seasons from 2015 to 2023were 0.083, 0.061, 0.050, and 0.059 mg/L, respectively. The effect of water level on TP was mainly observed during the low-water period. When the water level in the dry season rose to 12.25 and 13.00 m, the percentage of TP exceeding 0.1 mg/L in Longgan Lake decreased to 55.8% and 33.3%, respectively. During the dry season, wind and wave disturbances caused the release of endogenous phosphorus in Huayang Lakes. This led to drastic fluctuations in TP concentration, reducing the correlation between water level and TP. When external control is limited, the water level during the dry season should be maintained between 12.25 and 13.0 m. Additionally, it is necessary to accelerate the restoration of submerged macrophyte species(such as Hydrilla verticillata and Vallisneria natans) in the Huayang Rivers.

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基于概率统计及查询质量的数据源选择策略

计算机科学 2004年第11期31卷 102-104页

作者：张春海刘群李华中国海洋大学计算机科学系青岛266071

数据源选择策略对提高异构数据集成效率具有重要意义。综合考虑概率统计信息和数据源相对执行质量,提出一种新的数据源选择策略。概率统计信息通过分析查询日志得到,包括针对频繁主题类的数据源覆盖度和数据源集合重叠度。数据源相对执... 详细信息

数据源选择策略对提高异构数据集成效率具有重要意义。综合考虑概率统计信息和数据源相对执行质量,提出一种新的数据源选择策略。概率统计信息通过分析查询日志得到,包括针对频繁主题类的数据源覆盖度和数据源集合重叠度。数据源相对执行质量包括查询价格、执行时延、数据源可靠性和用户满意度。给出基于以上标准的数据源选择贪心算法,并通过实验原型验证算法有效性。

关键词：数据源查询异构数据集成日志贪心算法验证算法时延选择策略执行用户满意度