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ESD内镜术联合益胃四君子汤对慢性萎缩性胃炎癌前期病变黏膜修复血清调节功能及GSH-Px、HIF-1α、VEGF等指标的影响 被引量:5
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作者 宋炜 张佳 +1 位作者 马军伟 郝丹丹 《中华中医药学刊》 北大核心 2025年第2期237-240,共4页
目的探究血管内皮生长因子(ESD)联合益胃四君子汤对慢性萎缩性胃炎(CAG)癌前期病变患者黏膜修复血清调节功能及谷胱甘肽过氧化物酶(GSH-Px)、缺氧诱导因子(HIF)-1α、血管内皮生长因子(VEGF)等指标的影响。方法回顾性分析医院收治的CAG... 目的探究血管内皮生长因子(ESD)联合益胃四君子汤对慢性萎缩性胃炎(CAG)癌前期病变患者黏膜修复血清调节功能及谷胱甘肽过氧化物酶(GSH-Px)、缺氧诱导因子(HIF)-1α、血管内皮生长因子(VEGF)等指标的影响。方法回顾性分析医院收治的CAG癌前病变患者93例分组治疗,对照组46例予以胃复春片治疗,试验组47例予以益胃四君子汤治疗,比较两组治疗前后胃黏膜修复[表皮生长因子(EGF)、表皮生长因子受体(EGFR)]机制、血管生成(HIF-1α、VEGF)机制与血清p53、丙二醛(MDA)、GSH-Px的相关性及临床疗效比较。结果试验组治疗后1个月时的EGF、EGFR表达,HIF-1α、VEGF表达,血清p53、MDA表达显著均低于对照组,GSH-Px表达显著高于对照组(P<0.05),对照组患者总疗效(76.09%,35/46)明显低于试验组(91.49%,43/47)(P<0.05)。结论ESD内镜术联合益胃四君子汤能有效地降低CAG癌前病变患者的胃黏膜修复因子、血管生成因子的过表达,提高GSH-Px表达,有较好的临床疗效。 展开更多
关键词 esd内镜术 益胃四君子汤 慢性萎缩性胃炎癌前期病变 胃黏膜 p53 MDA GSH-PX 血管生成机制
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强化亲情护理在内镜中心行ESD治疗胃结肠息肉患者中的应用对患者满意度的提升效果分析
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作者 仇玕 《中文科技期刊数据库(文摘版)医药卫生》 2025年第2期191-194,共4页
分析在内镜中心行内镜黏膜下剥离术(ESD)治疗胃结肠息肉患者中应用强化亲情护理的效果。方法 研究节点于2023.5-2024.12,选取对象为在内镜中心行ESD治疗胃结肠息肉患者,数量计76例,以数字表随机分组处理,即:对照组(常规护理)、实验组(... 分析在内镜中心行内镜黏膜下剥离术(ESD)治疗胃结肠息肉患者中应用强化亲情护理的效果。方法 研究节点于2023.5-2024.12,选取对象为在内镜中心行ESD治疗胃结肠息肉患者,数量计76例,以数字表随机分组处理,即:对照组(常规护理)、实验组(常规护理联合强化亲情护理)。结果 实验组术后手术时间指标、心理状态、术后并发症、满意度评分更好,P<0.05。结论 为在内镜中心行ESD治疗胃结肠息肉患者实施强化亲情护理,能够更好地稳定患者的心理状态,确保ESD治疗顺利开展,显著提高患者对于临床实施护理措施的满意程度。 展开更多
关键词 胃结肠息肉患者 内镜中心 esd治疗 强化亲情护理
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基于0.18μm BCD工艺的抗辐射ESD防护器件GGNMOS优化设计 被引量:1
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作者 陆素先 程淩 +3 位作者 朱琪 李现坤 李娟 严正君 《电子与封装》 2025年第6期100-105,共6页
栅极接地N型金属氧化物半导体(GGNMOS)器件具有结构简单、响应迅速、泄放高效等多方面的优势,逐渐成为静电放电(ESD)防护结构中最常用的器件。但辐照试验时NMOS器件会受到多种辐射效应的影响,导致器件性能和可靠性下降。因此抗辐射电路... 栅极接地N型金属氧化物半导体(GGNMOS)器件具有结构简单、响应迅速、泄放高效等多方面的优势,逐渐成为静电放电(ESD)防护结构中最常用的器件。但辐照试验时NMOS器件会受到多种辐射效应的影响,导致器件性能和可靠性下降。因此抗辐射电路中GGNMOS器件的保护结构设计尤为困难。基于0.18μm BCD工艺,设计了一款有抗辐射需求的线性稳压器电路。根据各端口电压和工作特点设计该电路全芯片的ESD防护结构,通过试验分析得出GGNMOS保护结构的薄弱点并提出改进方案。实测结果显示,所设计的电路不仅满足100 krad(Si)的总剂量指标,还通过了2.5 kV的人体模型ESD测试。该研究为后续抗辐射电路中ESD器件设计提供了实验依据和理论指导。 展开更多
关键词 esd防护 栅接地NMOS 抗辐射 寄生三极管
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高速ESD保护低电容双向SCR
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作者 马超 贾义睿 +3 位作者 齐钊 陈泓全 魏敬奇 张波 《微电子学》 北大核心 2025年第1期147-152,共6页
针对在ESD防护中的系统设计对数据接口的传输速率与信号频率越来越高的要求,基于0.5μm BCD工艺,设计了一种具备低触发电压和低电容的双向SCR器件(LCDDSCR)。相较于常规的传统双向SCR器件结构(DDSCR),LCDDSCR结构采用临界扩散技术减小了... 针对在ESD防护中的系统设计对数据接口的传输速率与信号频率越来越高的要求,基于0.5μm BCD工艺,设计了一种具备低触发电压和低电容的双向SCR器件(LCDDSCR)。相较于常规的传统双向SCR器件结构(DDSCR),LCDDSCR结构采用临界扩散技术减小了P-well区的面积,实现了器件输入电容的降低。基于SCR器件的齐纳触发特性,通过临界齐纳注入技术引入ZP区使得器件的触发电压降低。传输线脉冲(TLP)测试与电容测试结果表明,LCDDSCR器件的触发电压为7.5 V,维持电压为1.5 V,结电容为0.53 pF,浪涌峰值电流达7 A,即0.53 pF/7 A,满足ESD防护要求的同时具备优秀的低电容与低触发电压特性。 展开更多
关键词 esd保护 SCR 低电容 低触发电压
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双向ESD保护器件电压对称性优化设计
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作者 刘宪成 陈秋芳 +2 位作者 王明辉 喻洋 张晶 《中国集成电路》 2025年第8期56-59,共4页
双向ESD保护器件具有双向保护能力,无论是正向还是反向电压超过其阈值,它都能有效地进行防护。它不仅能够防止来自外部的静电放电冲击,还能保护内部电路免受因信号反射或误操作引起的过压损害,在保护性能方面,双向ESD保护器件具有更高... 双向ESD保护器件具有双向保护能力,无论是正向还是反向电压超过其阈值,它都能有效地进行防护。它不仅能够防止来自外部的静电放电冲击,还能保护内部电路免受因信号反射或误操作引起的过压损害,在保护性能方面,双向ESD保护器件具有更高的灵活性。双向ESD保护器件通常要求双向击穿电压对称,因制造工艺难度较高,实际上较难做到很好的对称。本研究以NPN型双向ESD保护器件为研究对象,通过理论分析提出了一种双层基区的优化设计思路,并通过试验设计和TCAD仿真找到主要影响因素和初步的组合条件,再通过单因子试验确定了一组最优解,最后用数据验证了该方案的有效性。 展开更多
关键词 双向esd保护器件 NPN结构 双层基区
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Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins 被引量:1
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作者 Daiyu Hu Yuanqing Cao +6 位作者 Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan Qiong Lai Zhengliang Gao 《Neural Regeneration Research》 SCIE CAS 2025年第1期242-252,共11页
Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-li... Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies. 展开更多
关键词 cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells NEUROGENESIS NEUROTOXICOLOGY ORGANOIDS stem cells
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T型栅GaN HEMT微波器件ESD特性研究
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作者 倪志远 白霖 +2 位作者 林罡 鲍诚 章军云 《电子技术应用》 2025年第4期40-44,共5页
对Si基GaN HEMT器件在ESD事件下的失效机理与影响因素进行了研究。探究了器件在不同偏置下的失效电压分布情况,并结合微光显微镜定位了引起器件退化的异常点,进行了对应的微区分析。另外,还探究了T型栅几何尺寸如栅脚、栅帽宽度与总栅... 对Si基GaN HEMT器件在ESD事件下的失效机理与影响因素进行了研究。探究了器件在不同偏置下的失效电压分布情况,并结合微光显微镜定位了引起器件退化的异常点,进行了对应的微区分析。另外,还探究了T型栅几何尺寸如栅脚、栅帽宽度与总栅宽等工艺参数对器件抗静电能力的影响并进行相关机理分析,为器件ESD性能、可靠性的优化提供了方向与参考。 展开更多
关键词 GaN HEMT T型栅 esd 栅脚栅帽 总栅宽
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基于ESD算法的舆情研究——以中华传统文化为例
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作者 马丽 赵蕴涵 彭博 《晓庄学院自然科学学报》 北大核心 2025年第5期119-126,共8页
本研究结合Bert情感分析模型(Bidirectional Encoder Representations from Transformers)和LSTM(Long Short-Term Memory)时间序列预测模型,以中华传统文化为载体,构建了文化IP的预测模型。基于文化传播深度、文化影响力、受众反馈等... 本研究结合Bert情感分析模型(Bidirectional Encoder Representations from Transformers)和LSTM(Long Short-Term Memory)时间序列预测模型,以中华传统文化为载体,构建了文化IP的预测模型。基于文化传播深度、文化影响力、受众反馈等文化引导力因素,选取了10个能代表中华传统文化的关键词,运用该预测模型在国内外社交媒体进行相关数据的采集处理和情感分析,并根据爆发指数、情感指数和传播指数得出舆论影响文化IP的关键性指标ESD。结果表明,本研究能够制定适合互联网时代的中华文化传播路径,打造更具活力的文化IP,为新时期新业态的文化传播与出海提供思路。 展开更多
关键词 esd Bert LSTM 中华传统文化
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Challenges and development direction of deep fragmented soft coalbed methane in China 被引量:2
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作者 Yiyu Lu Guilin Zhao +7 位作者 Zhaolong Ge Yunzhong Jia Jiren Tang Tianyi Gong Shan Huang Zhongtan Li Wenyu Fu Jianyu Mi 《Earth Energy Science》 2025年第1期38-64,共27页
Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehens... Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehensive review of commonly employed coalbed methane extraction technologies.It then delves into several critical issues in the current stage of CBM exploration and development in China,including the compatibility of existing technologies with CBM reservoirs,the characteristics and occurrence states of CBM reservoirs,critical desorption pressure,and gas generation mechanisms.Our research indicates that current CBM exploration and development technologies in China have reached an internationally advanced level,yet the industry is facing unprecedented challenges.Despite progress in low-permeability,high-value coal seams,significant breakthroughs have not been achieved in exploring other types of coal seams.For different coal reservoirs,integrated extraction technologies have been developed,such as surface pre-depressurisation and segmented hydraulic fracturing of coal seam roof strata.Additionally,techniques like large-scale volume fracturing in horizontal wells have been established,significantly enhancing reservoir stimulation effects and coalbed methane recovery rates.However,all of these technologies are fundamentally based on permeation.These technologies lack direct methods aimed at enhancing the diffusion rate of CBM,thereby failing to fully reflect the unique characteristics of CBM.Current CBM exploration and development theories and technologies are not universally applicable to all coal seams.They do not adequately account for the predominantly adsorbed state of CBM,and the complex and variable gas generation mechanisms further constrain CBM development in China.Finally,continuous exploration of new deep CBM exploration technologies is necessary.Integrating more effective reservoir stimulation technologies is essential to enhance technical adaptability concerning CBM reservoir characteristics,gas occurrence states,and gas generation mechanisms,ultimately achieving efficient CBM development.We conclude that while China possesses a substantial foundation of deep fractured CBM resources,industry development is constrained and requires continuous exploration of new CBM exploration and development technologies to utilize these resources effectively. 展开更多
关键词 Deep coalbed methane Exploration and development technology Reservoir characteristics Critical desorption pressure Gas production mechanism development direction
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Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development 被引量:1
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作者 Baoqi Hu Rui Wang +8 位作者 Hanyue Zhang Xiou Wang Sijia Zhou Bo Ma Yan Luan Xin Wang Xinlin Chen Zhichao Zhang Qianyan Kang 《Neural Regeneration Research》 SCIE CAS 2025年第3期900-912,共13页
The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and contin... The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation. 展开更多
关键词 bipolar cells differentiation in vivo microglia Müller glia organotypic retinal explant culture postnatal retina development proliferation retinal progenitor cells
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New chapter in reform and development of organ donation and transplantation in China: Embracing past, grounding in national conditions, upholding steadfast belief, and looking forward to future 被引量:3
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作者 Hong-Tao Zhao Shu-Sen Zheng +12 位作者 Jia Fan Jia-Hong Dong Zhong-Hua Chen Wu-Jun Xue Qi-Fa Ye Hai-Bo Wang Jing-Yu Chen Zhe Zheng Feng Huo Xiao-Shun He Miao Pu Jie Zhao Jie-Fu Huang 《Hepatobiliary & Pancreatic Diseases International》 2025年第1期6-13,共8页
The reform stems from honesty and determination. Since 2005, organ donation and transplantation in China has undergone thorough reform, which complies with legislation requirements and ethical principles established b... The reform stems from honesty and determination. Since 2005, organ donation and transplantation in China has undergone thorough reform, which complies with legislation requirements and ethical principles established by the World Health Organization(WHO). Reform in China has demonstrated the unwavering confidence and utmost determination of the Chinese government and the Chinese transplantation community. The year 2015 marked a historic turning point when voluntary donations from Chinese citizens became the sole legitimate source for organ transplantation. Since 2015, China has gradually established and refined the “Chinese Mode” and “China System” for organ donation and transplantation, fulfilling its political pledge of reform, and has garnered international recognition, and fostered a social culture which promotes organ donation. This article reviewed the history of reform on organ donation and transplantation in China, presented a new pattern of establishment of organ donation system in the new era of the country, and the direction of advances in the future. 展开更多
关键词 Reform LEGISLATION Organ donation Organ transplantation Chinese mode High quality development
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Phenanthrene perturbs hematopoietic development and causes hematopoietic defects in zebrafish 被引量:1
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作者 Lingyu Ren Yue Wang +2 位作者 Ying Ren Guangke Li Nan Sang 《Journal of Environmental Sciences》 2025年第5期573-581,共9页
Phenanthrene(Phe)is one of the common polycyclic aromatic hydrocarbons in the environment,and recent studies show that it can cause cardiac developmental toxicity and immunotoxicity.However,it is still unknown whether... Phenanthrene(Phe)is one of the common polycyclic aromatic hydrocarbons in the environment,and recent studies show that it can cause cardiac developmental toxicity and immunotoxicity.However,it is still unknown whether it can affect the hematopoietic development in aquatic organisms.To address this question,zebrafish(Danio rerio)were chronically exposed to Phe at different concentrations.We found that Phe caused structural damage to the renal tubules in the kidney,induced malformed erythrocytes in peripheral blood,and decreased the proportion of myeloid cells in adult zebrafish,suggesting possible negative impacts that Phe posed to hematopoietic development.Then,using in situ hybridization technology,we found that Phe decreased the expression of primitive hematopoietic marker genes,specifically gata1 and pu.1,accompanied by an obstruction of primitive erythrocyte circulation.Furthermore,Phe impaired definitive hematopoiesis,increased aberrations of the transient hematopoietic site(PBI),and reduced the generation of hematopoietic stem cells,ultimately influencing the number of erythrocytes and myeloid cells.The findings suggested that Phe could induce hematopoietic toxicity in zebrafish embryos and pose unknown ecological risks. 展开更多
关键词 PHENANTHRENE ZEBRAFISH Hematopoietic development Hematopoietic defect
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Leucine-Rich Repeat Protein Family Regulates Stress Tolerance and Development in Plants 被引量:1
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作者 HAO Zhiqi WANG Tingyi +4 位作者 CHEN Dongdong SHEN Lan ZHANG Guangheng QIAN Qian ZHU Li 《Rice science》 2025年第1期32-43,共12页
The leucine-rich repeat(LRR)protein family is involved in a variety of fundamental metabolic and signaling processes in plants,including growth and defense responses.LRR proteins can be divided into two categories:tho... The leucine-rich repeat(LRR)protein family is involved in a variety of fundamental metabolic and signaling processes in plants,including growth and defense responses.LRR proteins can be divided into two categories:those containing LRR domains along with other structural elements,which are further subdivided into five groups,LRR receptor-like kinases,LRR receptor-like proteins,nucleotide-binding site LRR proteins,LRR-extensin proteins,and polygalacturonase-inhibiting proteins,and those containing only LRR domains.Functionally,various LRR proteins are primarily involved in plant development and responses to environmental stress.Notably,the LRR protein family plays a central role in signal transduction pathways related to stress adaptation.In this review,we classify and analyze the functions of LRR proteins in plants.While extensive research has been conducted on the roles of LRR proteins in disease resistance signaling,these proteins also play important roles in abiotic stress responses.This review highlights recent advances in understanding how LRR proteins mediate responses to biotic and abiotic stresses.Building upon these insights,further exploration of the roles of LRR proteins in abiotic stress resistance may aid efforts to develop rice varieties with enhanced stress and disease tolerance. 展开更多
关键词 leucine-rich repeat CLASSIFICATION FUNCTION stress tolerance plant development
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A new framework for rural development assessment from a systemic perspective: A case from karst mountainous areas in southwest China 被引量:1
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作者 Zhang Yiyi LI Yangbing 《Journal of Mountain Science》 2025年第4期1169-1188,共20页
The mountainous rural regions of China are undergoing enormous changes in space and time.To a certain extent,this change has increased the difficulties in our understanding of rural development in mountainous areas an... The mountainous rural regions of China are undergoing enormous changes in space and time.To a certain extent,this change has increased the difficulties in our understanding of rural development in mountainous areas and brought challenges to development policies and revitalization strategies in mountainous rural regions,especially in karst mountainous areas.In light of the difficulty in and as the key to the development of China's mountainous rural areas,the scientific and systematic construction of indicators for evaluating the level of rural revitalization development and clarifying the level of rural revitalization development and influential factors in karst mountainous areas are of great significance to the implementation of the development of the strategy for the revitalization of the rural areas in karst mountainous areas in China.This study constructed an evaluation index system of the rural regional system and rural revitalization development(RTSRD)from the perspective of rural regional system theory,assessed the spatial differentiation patterns and influential factors of RTSRD,and refined a typical territorial model of rural revitalization development in karst mountainous areas by taking Guizhou Province,a typical karst mountainous region,as a case study area.The evaluation and spatial analyses show that the RTSRD indices of karst mountainous areas in the system perspective show a linear growth trend in all single dimensions,with industrial revitalization(IR)showing the most significant increase each year.In time,the RTSRD of karst mountainous regions has developed from low to high,with evident improvement;spatially,the RTSRD shows the characteristics of‘high in the middle and low in the surroundings,and low in the plateau and low in the depression,'with apparent spatial heterogeneity.In addition,this study found that the spatial and temporal differences in RTSRD result from a combination of endogenous push and exogenous pull in the rural system.In particular,this study has refined a typical regional model of rural revitalization development in karst mountainous regions,which provides theoretical support and case practice for rural development in other karst mountainous regions.At the same time,it provides a basis for decision-making for the county level government and rural development planning. 展开更多
关键词 Karst mountains Rural development rural regional system Rural revitalization
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The formation,development and classification of rail corrugation:a survey on Chinese metro 被引量:1
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作者 Yang Wang Hong Xiao +3 位作者 Zhihai Zhang Xuhao Cui Yihao Chi Mahantesh M.Nadakatti 《Railway Engineering Science》 2025年第1期43-61,共19页
Investigations into rail corrugation within metro systems have traditionally focused on specific mechanisms,thereby limiting the generalizability of proposed theories.Understanding the commonalities in rail corrugatio... Investigations into rail corrugation within metro systems have traditionally focused on specific mechanisms,thereby limiting the generalizability of proposed theories.Understanding the commonalities in rail corrugation across diverse metro lines remains pivotal for elucidating its underlying mechanisms.The present study conducted extensive field surveys and tracking tests across 14 Chinese metro lines.By employing t-distributed stochastic neighbor embedding(t-SNE)for dimensional reduction and employing the unsupervised clustering algorithm DBSCAN,the research redefines the classification of metro rail corrugation based on characteristic information.The analysis encompassed spatial distribution and temporal evolution of this phenomenon.Findings revealed that floating slab tracks exhibited the highest proportion of rail corrugation at 47%.Notably,ordinary monolithic bed tracks employing damping fasteners were more prone to inducing rail corrugation.Corrugation primarily manifested in curve sections with radii between 300 and 500 m,featuring ordinary monolithic bed track and steel-spring floating slab track structures,with wavelengths typically between 30 and 120 mm.Stick–slip vibrations of the wheel–rail system maybe led to short-wavelength corrugations(40–60 mm),while longer wavelengths(200–300 mm)exhibited distinct fatigue damage characteristics,mainly observed in steel-spring floating slab tracks and small-radius curve sections of ordinary monolithic bed tracks and ladder sleeper tracks.A classification system comprising 57 correlated features categorized metro rail corrugation into four distinct types.These research outcomes serve as critical benchmarks for validating various theories pertaining to rail corrugation formation. 展开更多
关键词 METRO Rail corrugation Formation mechanism development law Field test
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Agricultural biotechnology in China:product development,commercialization,and perspectives 被引量:1
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作者 Jingang Liang Yu Sun +13 位作者 Yanchao Yang Zeyu Wang Han Wu Taotao Gu Ruifu Zhang Xinli Sun Bin Yao Tao Tu Xiaoqing LiuHuiying Luo Guangzhi Tong Yue Jiao Kui Li Jie Zhang Kongming Wu 《aBIOTECH》 2025年第2期284-310,共27页
Meeting the increasing demand for food and industrial products by the growing global population requires targeted efforts to improve crops,livestock,and microorganisms.Modern biotechnology,particularly genetic modific... Meeting the increasing demand for food and industrial products by the growing global population requires targeted efforts to improve crops,livestock,and microorganisms.Modern biotechnology,particularly genetic modification(GM)and genome-editing(GE)technologies,is crucial for food security and environmental sustainability.China,which is at the forefront of global biotechnological innovation and the rapid advancements in GM and GE technologies,has prioritized this field by implementing strategic programs such as the National High-tech Research&Development Program in 1986,the National Genetically Modified Organism New Variety Breeding Program in 2008,and the Biological Breeding-National Science and Technology Major Project in 2022.Many biotechnological products have been widely commercialized in China,including biofertilizers,animal feed,animal vaccines,pesticides,and GM crops such as cotton(Gossypium hirsutum),maize(Zea mays),and soybean(Glycine max).In this review,we summarize progress on the research and utilization of GM and GE organisms in China over the past 3 decades and provide perspectives on their further development.This review thus aims to promote worldwide academic exchange and contribute to the further development and commercial success of agricultural biotechnology. 展开更多
关键词 Agricultural biotechnology China Genetically modified organisms Product development COMMERCIALIZATION PERSPECTIVES
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Coupling and Spatial Disparities of Regional Economy and Ecosystem in High-Quality Town Development 被引量:2
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作者 Xinyi Ren Xiaowen Tan +2 位作者 Dan Luo Rongxin Lu Chien-Chi Chu 《Research in Ecology》 2025年第1期15-29,共15页
This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expan... This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expansion with environmental protection,a comprehensive evaluation index system is constructed,encompassing two key dimensions:regional economy and ecological environment.Using panel data from 2013 to 2022,the coupling coordination degree model is employed to quantify the interactions and synergy between these dimensions.Additionally,spatial econometric methods are applied to calculate both global and local Moran’s Index,revealing spatial clustering patterns,regional disparities,and heterogeneity.The relative development model further identifies critical factors influencing regional coordination,with a focus on the lagging development of basic infrastructure and public services.The findings demonstrate a positive temporal trend toward improved regional coordination and reduced development gaps,with a spatial pattern characterized by higher coupling degrees in eastern and central regions compared to western areas.Based on these results,this study proposes actionable strategies to enhance coordinated development,emphasizing ecological conservation,the establishment of green production and consumption systems,ecological restoration,and strengthened municipal collaboration.This revised abstract emphasizes the study’s purpose,methods,and key findings more clearly while maintaining a professional and concise tone.Finally,based on the above analysis results,the corresponding coordinated development suggestions of regional economy and ecological environment are given from the aspects of ecological environment protection measures,green production and consumption system construction,ecological environment restoration and municipal coordination. 展开更多
关键词 Regional Economies Ecological Environment Coupling Coordination Degree Spatiotemporal Distribution Characteristics Relative development Model
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Dynamic DNA methylation modification in catechins and terpenoids biosynthesis during tea plant leaf development 被引量:1
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作者 Jiahao Chen Yang Hu +3 位作者 Zhangsheng Zhu Peng Zheng Shaoqun Liu Binmei Sun 《Horticultural Plant Journal》 2025年第2期906-920,共15页
DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Ca... DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Camellia sinensis).In this study,we combined the methylome,transcriptome,and metabolome to investigate the dynamic changes in DNA methylation and its potential regulatory roles in secondary metabolite biosynthesis.In this study,the level of genomic DNA methylation increased as leaf development progressed from tender to old leaf.It additionally exhibited a similar distribution across the genomic background at the two distinct developmental stages studied.Notably,integrated analysis of transcriptomic and methylomic data showed that DNA hypermethylation primarily occurred in genes of the phenylpropanoid,flavonoid,and terpenoid biosynthesis pathways.The effect of methylation on transcription of these secondary metabolite biosynthesis genes was dependent on the location of methylation(i.e.,in the promoter,gene or intergenic regions)and the sequence context(i.e.,CpG,CHG,or CHH).Changes in the content of catechins and terpenoids were consistent with the changes in gene transcription and the methylation state of structural genes,such as serine carboxypeptidase-like acyltransferases 1A(SCPL1A),leucoanthocyanidin reductase(LAR),and nerolidol synthase(NES).Our study provides valuable information for dissecting the effects of DNA methylation on regulation of genes involved in secondary metabolism during tea leaf development. 展开更多
关键词 Camellia sinensis DNA methylation leaf development CATECHINS TERPENOIDS Gene regulation
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New aspects of a small GTPase RAB35 in brain development and function
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作者 Ikuko Maejima Ken Sato 《Neural Regeneration Research》 SCIE CAS 2025年第7期1971-1980,共10页
In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting t... In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting the cargo of proteins,lipids,and other molecules to appropriate compartments via transport vesicles or intermediates.These processes are strictly regulated by various small GTPases such as the RAS-like in rat brain(RAB)protein family,which is the largest subfamily of the RAS superfamily.Dysfunction of membrane trafficking affects tissue homeostasis and leads to a wide range of diseases,including neurological disorders and neurodegenerative diseases.Therefore,it is important to understand the physiological and pathological roles of RAB proteins in brain function.RAB35,a member of the RAB family,is an evolutionarily conserved protein in metazoans.A wide range of studies using cultured mammalian cells and model organisms have revealed that RAB35 mediates various processes such as cytokinesis,endocytic recycling,actin bundling,and cell migration.RAB35 is also involved in neurite outgrowth and turnover of synaptic vesicles.We generated brain-specific Rab35 knockout mice to study the physiological roles of RAB35 in brain development and function.These mice exhibited defects in anxiety-related behaviors and spatial memory.Strikingly,RAB35 is required for the precise positioning of pyramidal neurons during hippocampal development,and thereby for normal hippocampal lamination.In contrast,layer formation in the cerebral cortex occurred superficially,even in the absence of RAB35,suggesting a predominant role for RAB35 in hippocampal development rather than in cerebral cortex development.Recent studies have suggested an association between RAB35 and neurodegenerative diseases,including Parkinson's disease and Alzheimer's disease.In this review,we provide an overview of the current understanding of subcellular functions of RAB35.We also provide insights into the physiological role of RAB35 in mammalian brain development and function,and discuss the involvement of RAB35 dysfunction in neurodegenerative diseases. 展开更多
关键词 ENDOCYTOSIS ENDOSOMES hippocampal development neurodegenerative diseases RAB35
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Comprehensive characterization of lncRNA N^(6)-methyladenosine modification dynamics throughout bovine skeletal muscle development 被引量:1
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作者 Cui Mao Wei You +4 位作者 Yuta Yang Haijian Cheng Xin Hu Xianyong Lan Enliang Song 《Journal of Animal Science and Biotechnology》 2025年第3期1025-1040,共16页
Background N^(6)-methyladenosine(m^(6)A)methylation is a key epigenetic modification that can modulate gene expression and strongly affect mammalian developmental processes.However,the genome-wide methylation of long ... Background N^(6)-methyladenosine(m^(6)A)methylation is a key epigenetic modification that can modulate gene expression and strongly affect mammalian developmental processes.However,the genome-wide methylation of long non-coding RNAs(lncRNAs)and its implications for the development of skeletal muscle remain poorly understood.Bovine skeletal muscle samples from five developmental stages were analyzed in this study to establish lncRNA methylome and transcriptomic maps.Results Globally,59.67%of lncRNAs in skeletal muscle with m^(6)A modifications,and this percentage decreased progressively during development.lncRNA expression levels were positively associated with the number of m^(6)A peaks,with lncRNAs possessing 3 or more peaks showing significantly higher expression levels than those with 1 or 2 peaks.Specific lncRNAs involved in skeletal muscle development were identified through two analytical approaches.The first approach employed weighted gene co-expression network analysis(WGCNA)of transcriptomic data to identify correlations between annotated lncRNAs and growth-related traits,resulting in 21 candidate hub lncRNAs.The intersection of these 21 hub lncRNAs with 151 differentially methylated lncRNAs(DM-lncRNAs)identified 10 shared candidate lncRNAs.The second approach integrated MeRIP-seq and RNA-seq data to identify 36 lncRNAs that were both differentially m^(6)A modified and differentially expressed(dme-lncRNAs).GO and KEGG enrichment analyses of cis-target genes associated with these dme-lncRNAs identified eight candidate lncRNAs.Combining the results from the two approaches identified 16 key m^(6)A-modified lncRNAs likely involved in skeletal muscle development.Conclusions These findings highlight the regulatory and functional significance of dynamic lncRNA methylation in skeletal muscle development. 展开更多
关键词 BOVINE LncRNA m^(6)A methylation Muscle development
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