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New insight into the origin and evolution of the flora and fauna of Hainan Island, China

Science China Earth Sciences 2025年第1期 52-61页

作者： Hua zhu Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Yunnan International Joint Laboratory of Southeast Asia Biodiversity Conservation Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants

The origin of the biota of Hainan Island, China, remains a fundamental scientific problem. Comparative studies on the biota, geological tectonics, and paleomagnetism proposed that during the Eocene, Hainan Island connected Vietnam and Guangxi, and then moved to the southeast to reach its present location. This review mainly discusses its biota origin from molecular phylogeny and palaeobotanical research. The formation and evolution of the biological groups of Hainan Island were identified via research on their genomes, phylogeny, and molecular biogeography. This research showed that the genera and species that appeared and diverged early in their evolution(i.e., before the Miocene) can be explained by the land connection between Hainan Island, Vietnam, and Guangxi during the Eocene-Oligocene. According to Southeast Asian tectonic theory, in the Middle Miocene(at about 15 million years ago), Hainan Island had moved to its present position. The population and genetic divergence of species with late divergence times(after 15 Ma) can be reasonably explained by the close proximity(or land connection) between Hainan Island and the Leizhou Peninsula, enabling genetic communication between Hainan Island and the Chinese mainland, but have exceptional cases. Conclusions have been obtained through palaeobotanical studies, showing that in the Eocene-Oligocene period, southwest China and Hainan Island had subtropical vegetation and flora. However, the fossil group in southeast China(in Maoming, near present-day Hainan Island) in the Late Eocene indicated a tropical rainforest vegetation and flora. This suggests that in the Paleogene, Hainan Island may have been located near or on the southwest border of Guangxi and northern Vietnam, rather than in its present location. The floristic division of the flora of Hainan Island basically presents a northeast-southwest inclined distribution pattern. This pattern can be explained by the counterclockwise rotation of Hainan Island during i

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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期 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.

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Review of precipitation strengthening in ultrahigh-strength martensitic steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 256-269页

作者： Zhihao Tian Chunlei Shang Chaolei Zhang Xiaoye Zhou Honghui Wu Shuize Wang Guilin Wu Junheng Gao Jiaming zhu Xinping Mao Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Institute of Steel Sustainable Technology Liaoning Academy of MaterialsShenyang 110004China Department of Materials Science and Engineering Shenzhen MSU-BIT UniversityShenzhen 518172China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China School of Civil Engineering Shandong UniversityJinan 250061China

Martensite is an important microstructure in ultrahigh-strength steels,and enhancing the strength of martensitic steels often involves the introduction of precipitated phases within the martensitic *** considerable research efforts devoted to this area,a systematic summary of these advancements is *** review focuses on the precipitates prevalent in ultrahigh-strength martensitic steel,primarily carbides(e.g.,MC,M_(2)C,and M_(3)C)and intermetallic compounds(e.g.,Ni Al,Ni_(3)X,and Fe_(2)Mo).The precipitation-strengthening effect of these precipitates on ultrahigh-strength martensitic steel is discussed from the aspects of heat treatment processes,microstructure of precipitate-strengthened martensite matrix,and mechanical ***,a perspective on the development of precipitation-strengthened martensitic steel is presented to contribute to the advancement of ultrahigh-strength martensitic *** review highlights significant findings,ongoing challenges,and opportunities in the development of ultrahigh-strength martensitic steel.

关键词： ultrahigh-strength martensitic steel precipitation strengthening mechanical property carbide intermetallic compound

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多中心临床观察铝碳酸镁四联与铋剂四联根除幽门螺杆菌的疗效及安全性

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胃肠病学和肝病学杂志 2022年第6期31卷 648-655页

作者：贾燕潘元明盛剑秋朱云清刘改芳郭晓峰范如英王萍吴婧张丽敏中国人民解放军总医院第七医学中心消化内科北京100700 陕西省人民医院消化内科河北省人民医院消化内科山西省人民医院消化内科

目的探讨并比较铝碳酸镁四联与铋剂四联根除幽门螺杆菌(Helicobacter pylori,***)的疗效及安全性。方法采用前瞻性随机对照多中心临床研究,对象为^(13)C尿素呼气试验阳性者,于2018年3月至2020年1月共入组400例,最终符合统计标准的患者35... 详细信息

目的探讨并比较铝碳酸镁四联与铋剂四联根除幽门螺杆菌(Helicobacter pylori,***)的疗效及安全性。方法采用前瞻性随机对照多中心临床研究,对象为^(13)C尿素呼气试验阳性者,于2018年3月至2020年1月共入组400例,最终符合统计标准的患者357例(剔除因个人原因和未按要求服药的14例及失访的29例),其中铝碳酸镁四联组179例,铋剂四联组178例。铝碳酸镁四联组:铝碳酸镁1000 mg tid+雷贝拉唑钠10 mg bid+阿莫西林1000 mg bid+克拉霉素500 mg bid;铋剂四联组:胶体果胶铋300 mg bid+雷贝拉唑钠10 mg bid+阿莫西林1000 mg bid+克拉霉素500 mg bid,疗程均为10 d。治疗结束至少28 d后所有患者均接受^(13)C尿素呼气试验检测,评估并比较两组***根除率、症状缓解情况及安全性(不良反应发生率)。结果(1)***根除率:铝碳酸镁四联组为77.7%,铋剂四联组为82.0%,两组比较差异无统计学意义(P>0.05)。(2)影响***根除失败的单因素分析或多因素分析发现,***根除率在吸烟者中为71.8%,不吸烟者为82.1%,两组比较差异有统计学意义(P0.05)。透射电镜结果显示铝碳酸镁四联组对保持胃亚细胞器结构(尤其是线粒体结构)的完整性优于铋剂四联组,扫描电镜发现感染***的胃黏膜组织经根除***后腺管开口均一,渗出消失,其中铝碳酸镁四联组较铋剂四联组恢复更好(P=0.035)。(4)不良反应发生率:铝碳酸镁四联组为10.6%(19/179),铋剂四联组为27.0%(48/178);单纯因铝碳酸镁四联组治疗方案引起的不良反应占比4.5%(8/179),铋剂四联组治疗方案引起的不良反应为21.3%(38/178),两组比较差异均有统计学意义(P<0.05)。结论吸烟可能影响***根除疗效;铝碳酸镁四联与铋剂四联根除***疗效相当,但不良反应率更低,可能与铝碳酸镁保护胃黏膜线粒体亚细胞器相关。

关键词：胃黏膜感染幽门螺杆菌铝碳酸镁药物组合疗法根除率

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Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Lithium-sulfur batteries Staged dendrite suppression Shuttle effect Surface-negatively-charged nanodiamond

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Nanoparticles for the treatment of spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1665-1680页

作者： Qiwei Yang Di Lu Jiuping Wu Fuming Liang Huayi Wang Junjie Yang Ganggang Zhang Chen Wang Yanlian Yang Ling zhu Xinzhi Sun Department of Orthopedic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Key Laboratory for Biomedical Effects of Nanomaterials and NanosafetyCAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijingChina University of Chinese Academy of Sciences BeijingChina Department of Neurosurgery The First Affiliated Hospital of Chongqing Medical UniversityChongqingChina

Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development.

关键词： antioxidants axon regeneration biocompatible materials drug carriers nanoparticles nerve regeneration neuroinflammatory diseases neuroprotection spinal cord injury stem cells

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EZH2-dependent myelination following sciatic nerve injury

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Neural Regeneration Research 2025年第8期20卷 2382-2394页

作者： Hui zhu Li Mu Xi Xu Tianyi Huang Ying Wang Siyuan Xu Yiting Wang Wencong Wang Zhiping Wang Hongkui Wang Chengbin Xue Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityKey Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo-innovation Center of NeuroregenerationNMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina Medical School of Nantong University NantongJiangsu ProvinceChina Department of Neurology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Rehabilitation Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Critical Care Medicine Nantong Fourth People’s HospitalNantongJiangsu ProvinceChina

Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve ***,the gene regulatory network of regenerated myelin differs from that of native *** of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of Schwann cells in *** further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in Schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were *** results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain *** highlights the crucial role of Ezh2 in initiating Schwann cell ***,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type *** suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and *** conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve *** EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.

关键词： demyelination EZH2 myelination peripheral nerve injury PRC2 remyelination Schwann cells sciatic nerve crush sciatic nerve transection

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基于大数据和无线网络的采摘机器人定位技术研究

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农机化研究 2025年第1期47卷 194-198页

作者：朱雯曦绍兴职业技术学院信息工程学院浙江绍兴312000

分析了5G无线网络定位原理,提出了单基站定位技术和加权质心的5G定位技术,设计了采摘机器人定位系统硬件部分,并基于大数据和无线网络实现了采摘机器人定位系统。试验结果表明:系统具有较好的定位精度,优于单基站定位方法精度,且其定位... 详细信息

分析了5G无线网络定位原理,提出了单基站定位技术和加权质心的5G定位技术,设计了采摘机器人定位系统硬件部分,并基于大数据和无线网络实现了采摘机器人定位系统。试验结果表明:系统具有较好的定位精度,优于单基站定位方法精度,且其定位曲线与北斗定位设备曲线拟合度非常高,稳定性较好。

关键词：采摘机器人 5G无线网络定位单基站加权质心大数据

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基于人工神经网络和机器视觉的棉花分拣系统研究

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农机化研究 2025年第4期47卷 208-212页

作者：朱西方河南工业职业技术学院河南南阳473000

首先,介绍了卷积神经网络的原理,并基于双目视觉搭建了棉花分拣视觉系统;然后,基于3×3窗口、Sobel和Hough等算法,实现了棉花图像的边缘检测和特征提取功能;最后,基于卷积神经网络对棉花图像进行特征提取和优劣分类,并利用双目视觉对识... 详细信息

首先,介绍了卷积神经网络的原理,并基于双目视觉搭建了棉花分拣视觉系统;然后,基于3×3窗口、Sobel和Hough等算法,实现了棉花图像的边缘检测和特征提取功能;最后,基于卷积神经网络对棉花图像进行特征提取和优劣分类,并利用双目视觉对识别的棉花进行空间定位。实验结果表明:棉花分拣系统的准确率为96.50%,能够有效地满足实际应用的要求。

关键词：棉花分拣系统卷积神经网络双目视觉 Sobel Hough

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Buried interface bridging for inverted cesium-formamidinium triiodide perovskite solar cells with long operational stability

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Science China Chemistry 2025年第01期 163-173页

作者： Chenhui Zhang Chunjun Liang Fulin Sun Ting zhu Xinghai Huang Yuzhu Guo Xinyu Guo Kunyang Ge Dan Li Fangtian You Zhiqun He Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic TechnologyBeijing Jiaotong University Department of Physics School of Physical Science and Engineering Beijing Jiaotong University

In the field of perovskite solar cells(PSCs), the research on defects in the buried interface has been relatively limited due to its non-exposure; however, this interface significantly impacts the performance enhancement of inverted PSCs. This study employs phenylethylammonium chloride(PEACl) molecules as a buffer layer to modify the buried interface of p-i-n structured PSCs,aiming to enhance the uniformity of self-assembled monolayers(SAMs) and facilitate the uniform nucleation and growth of perovskite films on the substrate. Furthermore, the introduction of the PEACl buffer layer effectively passivates defects at the bottom of the perovskite layer and notably enhances the crystal quality of the perovskite film by mitigating residual stress,thereby reducing nonradiative recombination loss. Following these optimizations, the MA-free PSCs treated with PEACl achieve a power conversion efficiency(PCE) of 24.11%, with significant improvements in storage, thermal stability, and operational stability. Particularly noteworthy is the device's performance in an unencapsulated state, whereas after 1,500 hours of continuous light operation stability testing, it retains 97% of its original efficiency. This study not only enriches the systematic understanding of the characteristics of the buried interface in PSCs but also contributes significantly to advancing the commercial production of perovskite photovoltaic technology.

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