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Differences in drought effects on carbon fluxes in vegetation in arid and humid regions
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作者 Danna Chen Daodao Pan +1 位作者 Enbin Liu Xiaojun Xu 《Journal of Forestry Research》 2026年第1期78-97,共20页
Drought influences carbon fixation by plants.Therefore,elucidating its impact on carbon fluxes in plants at the ecosystem level is crucial for assessing their role in mitigating climate change.Using carbon fluxes and ... Drought influences carbon fixation by plants.Therefore,elucidating its impact on carbon fluxes in plants at the ecosystem level is crucial for assessing their role in mitigating climate change.Using carbon fluxes and environmental factor data from FLUXNET sites,we analyzed the influence of drought on carbon fluxes,their drivers,time-lag effects,and recovery times across various climatic regions and seasons.Results showed drought significantly decreased gross primary production(GPP),ecosystem respiration,and net ecosystem productivity in arid regions but slightly increased carbon sequestration in humid regions.Summer droughts negatively affected vegetation carbon fluxes,partly offset by the positive impact of spring droughts.Nonforest carbon fluxes were more susceptible to drought effects than forest fluxes.Soil water content(SWC)was the main influence on changes in arid regions,whereas vapor pressure deficit(VPD)dominated humid regions.Decreased SWC and increased VPD reduced carbon sequestration in arid regions but increased it in humid regions.Increased VPD reduced GPP,leading to forest carbon loss,whereas decreased SWC reduced GPP,leading to nonforest carbon loss.The lag time of the drought effects on carbon fluxes was longer in humid regions(19.44 d)than in arid regions(14.71 d).Compared to nonforest areas(16.74 d and 57 d for drought lag and recovery time,respectively),forest areas had a longer lag(18.81 d)and recovery time(92 d).The findings revealed discrepancies in the main factors regulating vegetation carbon fluxes during droughts between arid and humid regions and between forest and nonforest ecosystems.These insights provide a new perspective on understanding and simulating carbon-climate feedback.Enhancing ecosystem diversity is a feasible measure to increase drought resistance. 展开更多
关键词 Carbon sequestration Regulatory factor Drought lag time Recovery time Climatic regions
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Spatio-temporal responses of ecological resilience to urbanization in five Great Lakes Regions(GLRs)in China and implications for building resilient GLRs
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作者 Tongning Li Guoen Wei +4 位作者 Minghui Xu Daozheng Li Weifeng Deng Yaobin Liu Bao-Jie He 《Geography and Sustainability》 2026年第1期218-231,共14页
Great Lakes Regions(GLRs)in China often confront landscape fragmentation,wetland degradation,and ecological resilience(ER)losses owing to extensive and intensive urbanization.In GLRs,however,the ER responses to urbani... Great Lakes Regions(GLRs)in China often confront landscape fragmentation,wetland degradation,and ecological resilience(ER)losses owing to extensive and intensive urbanization.In GLRs,however,the ER responses to urbanization remain unclear.This study explored the spatiotemporal evolution of ER and urbanization in five GLRs in China to analyze the ER dynamic patterns along center−lakeside−periphery gradient.The Spatial Durbin Model(SDM)and Panel Threshold Model(PTM)were combined to reveal the spillover and threshold effects of urbanization in five GLRs.The results indicate that the ER in five GLRs declined with a rate of 21%from 2000 to 2020.There was a clear“center-periphery”contraction trend with low ER areas primarily spreading to human activity-concentrated regions such as lakesides,riversides,and road networks.Driven by economic and land urbanization,the average urbanization level increased from 0.06 to 0.13,where lakesides,riversides,and road networks were key areas undergoing expansion.The urbanization showed a noticeable negative spatial spillover effect on ER.Away from central lakes,the negative impacts on ER exhibited a two-phase decrease with the threshold of 81 km.This study contributes to the understanding of human-environment interactions by examining the ecological resilience response process of GLRs under the impact of urbanization.Based on a multidimensional“center−lakeside−periphery”analytical model,this study provides a strategic framework for ecological construction in GLRs in China,promoting sustainable development and adaptive capacity in vulnerable areas. 展开更多
关键词 Ecological resilience URBANIZATION Spatial durbin model Panel threshold model Great Lakes Region
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Predicting the temperature of CRTS III ballastless tracks in cold regions based on a TCN-Track model
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作者 Jie LIANG Shijie DENG +4 位作者 Juanjuan REN Wenlong YE Kaiyao ZHANG Dacheng LI Ronghe ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2026年第1期43-57,共15页
The uneven distribution of the temperature field in the track structure,caused by various meteorological factors such as extremely low temperatures and snowfall,leads to significant temperature loads and is the primar... The uneven distribution of the temperature field in the track structure,caused by various meteorological factors such as extremely low temperatures and snowfall,leads to significant temperature loads and is the primary cause of damage to China Railway Track System(CRTS)III ballastless tracks in cold regions during service.In this study,to predict the temperature of the track structure accurately,we analyzed meteorological data collected from Shenyang,China,and identified the factors that had the most effect on the track temperature field.We propose a temporal convolutional network(TCN)-based temperature field prediction model for ballastless tracks(TCN-Track model),which enhances the ability to extract and fuse local and global features from complex long-term meteorological data.The results indicate that the proposed TCN-Track model performs well in predicting track temperature fields from meteorological data,with a mean absolute error(MAE)ranging from 0.26 to 0.39,a root mean square error(RMSE)ranging from 0.32 to 0.50,and correlation coefficient(R)values ranging from 0.888 to 0.985.Compared with a long short-term memory(LSTM)model,the MAE of the TCN-Track model is reduced by 89.17%and the RMSE by 88.51%.This method offers a new solution for accurately predicting the temperature field of ballastless tracks in cold regions,aiding in predicting and preventing track damage caused by low temperatures. 展开更多
关键词 Cold regions CRTS III ballastless tracks Temperature prediction Meteorological variables Time prediction model
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Ecosystem management and agricultural green development in subtropical regions
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作者 Jinshui Wu Tony G.O’Donnell +4 位作者 Andrew Macrae Hongsong Chen Weiguo Cheng Zhihong Xu Zhengmiao Deng 《Journal of Integrative Agriculture》 2026年第2期399-401,共3页
The United Nations Sustainable Development Goal(SDG) 2 aims to achieve Zero Hunger by 2030.However,global hunger and food insecurity have continued to rise at an alarming rate(UN 2023).Subtropical regions are home to ... The United Nations Sustainable Development Goal(SDG) 2 aims to achieve Zero Hunger by 2030.However,global hunger and food insecurity have continued to rise at an alarming rate(UN 2023).Subtropical regions are home to more than 30% of the world's population,predominantly in developing countries where per capita farmland and food supply are only 40% of those in developed nations(FAO 2018).Meeting the Zero Hunger target amid ongoing population growth in these regions requires a substantial increase in agricultural production while minimizing soil degradation and adverse ecological impacts.This challenge is shared by many countries across South Asia,Africa,and Central and South America. 展开更多
关键词 ecosystem management developing countries subtropical regions sustainable development goal agricultural green development zero hunger sustainable development goal sdg population growth
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一种多普勒匹配搜索的快速TMA方法
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作者 徐景峰 刘建波 +1 位作者 舒象兰 李智忠 《舰船科学技术》 北大核心 2025年第19期162-167,共6页
针对低信噪比和干扰线谱情况下,利用方位和频率测量信息解算目标运动要素存在收敛时间长和解算结果不可靠性的问题。本文提出一种多普勒匹配搜索的快速TMA(Target Motion Analysis)方法,通过对多普勒搜索补偿和相干累积,当目标要素与实... 针对低信噪比和干扰线谱情况下,利用方位和频率测量信息解算目标运动要素存在收敛时间长和解算结果不可靠性的问题。本文提出一种多普勒匹配搜索的快速TMA(Target Motion Analysis)方法,通过对多普勒搜索补偿和相干累积,当目标要素与实际情况完全匹配时,只有目标线谱能得到相干叠加,而噪声和其他干扰线谱均无法得到增强。实验结果表明,该方法无需事先辨认目标线谱和干扰线谱,通过相干累积提升了信噪比,可以快速匹配得到目标运动要素,能适应低信噪比条件且解算收敛速度快,具有较好的应用前景。 展开更多
关键词 tma 线谱 多普勒搜索 相干累积
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黑逍遥散调控TMA/FMO3/TMAO代谢通路抑制神经炎症改善APP/PS1小鼠的认知障碍 被引量:1
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作者 杨娇 陈怡琴 +2 位作者 裴文丽 韩玉梅 王虎平 《中国实验方剂学杂志》 北大核心 2025年第19期171-180,共10页
目的:该研究探讨黑逍遥散通过调控三甲胺(TMA)/肝黄素单加氧酶3(FMO3)/氧化三甲胺(TMAO)代谢通路对APP/PS1小鼠神经炎症的干预作用。方法:选取4月龄SPF级APP/PS1雄性小鼠60只按随机数字表法分为模型组,双歧杆菌四联活菌片组,盐酸多奈哌... 目的:该研究探讨黑逍遥散通过调控三甲胺(TMA)/肝黄素单加氧酶3(FMO3)/氧化三甲胺(TMAO)代谢通路对APP/PS1小鼠神经炎症的干预作用。方法:选取4月龄SPF级APP/PS1雄性小鼠60只按随机数字表法分为模型组,双歧杆菌四联活菌片组,盐酸多奈哌齐组及黑逍遥散高、中、低剂量组,连续灌胃90 d;10只同月龄、同系的雄性野生型C57BL/6J小鼠作为空白组。旷场实验检测小鼠的自主活动,Morris水迷宫实验测试小鼠学习记忆能力,尼色染色观察各组小鼠海马神经元的形态,酶联免疫吸附测定法(ELISA)检测小鼠海马组织中白细胞介素(IL)-1β、IL-18和小鼠血清中tau、磷酸化(p)-tau(Thr181)、p-tau(Thr231)、p-tau(Ser262)、p-tau(Ser396)的表达,液相色谱-质谱联用技术(LC-MS)分析检测小鼠血清中TMAO的水平,蛋白免疫印迹法(Western blot)检测小鼠肝脏中FMO3和海马中NOD样受体蛋白3(NLRP3)、凋亡相关斑点样蛋白(ASC)、胱天蛋白酶-1(Caspase-1)蛋白的表达。结果:与空白组比较,模型组小鼠在旷场实验中总路程、进入中央区次数、中央区域活动路程均减少(P<0.01);第3、4天定位航行实验中逃避潜伏期时间延长而穿越平台次数减少(P<0.01);海马神经元细胞结构异常,尼氏体模糊;海马组织中IL-1β、IL-18及血清中tau、p-tau(Thr181)、p-tau(Thr231)、p-tau(Ser262)、p-tau(Ser396)水平及TMAO含量增加(P<0.05,P<0.01);肝脏组织中FMO3蛋白表达上升及海马组织中NLRP3、ASC、Caspase-1蛋白表达上升(P<0.01)。与模型组比较,双歧杆菌四联活菌片组、盐酸多奈哌齐组、黑逍遥散高剂量组小鼠活动的总路程、中央区域活动路程、第3天和第4天的逃避潜伏期降低(P<0.05,P<0.01),进入中央区次数及穿越平台次数均增加(P<0.05,P<0.01);各给药组中海马神经元损伤得到改善、肝脏组织中FMO3蛋白和海马组织中Caspase-1蛋白表达下降及小鼠海马组织中IL-1β、IL-18和小鼠血清中tau、p-tau(Thr181)、p-tau(Thr231)、p-tau(Ser262)、p-tau(Ser396)水平降低(P<0.05,P<0.01);双歧杆菌四联活菌片组、盐酸多奈哌齐组、黑逍遥散中高剂量组小鼠血清中TMAO含量和海马组织中NLRP3和ASC蛋白表达下降(P<0.05,P<0.01)。结论:黑逍遥散可改善APP/PS1小鼠的认知障碍,其作用机制可能与调控TMA/FMO3/TMAO代谢通路以抑制神经炎症有关。 展开更多
关键词 阿尔茨海默病 黑逍遥散 三甲胺(tma)/肝黄素单加氧酶3(FMO3)/氧化三甲胺(tmaO)代谢通路 神经炎症 认知障碍
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基于肠道菌群驱动TMA/FMO3/TMAO通路探讨健脾化浊调脂方治疗动脉粥样硬化的机制 被引量:2
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作者 黄浪浪 刘中勇 刘言薇 《中国中医基础医学杂志》 2025年第6期998-1004,共7页
目的探讨健脾化浊调脂方抗动脉粥样硬化(atherosclerosis,AS)的可能作用机制。方法采用高胆碱饮食建立AS动物模型。将60只ApoE^(-/-)小鼠随机分为ApoE^(-/-)对照组,模型组,抗生素组,健脾化浊调脂方低、中、高剂量组,每组10只。另取20只C... 目的探讨健脾化浊调脂方抗动脉粥样硬化(atherosclerosis,AS)的可能作用机制。方法采用高胆碱饮食建立AS动物模型。将60只ApoE^(-/-)小鼠随机分为ApoE^(-/-)对照组,模型组,抗生素组,健脾化浊调脂方低、中、高剂量组,每组10只。另取20只C57BL/6J小鼠随机分为空白对照组和胆碱对照组。空白对照组和ApoE^(-/-)对照组给予等体积0.9%氯化钠溶液灌胃,其余各组给予1%氯化胆碱灌胃。造模16周后采用HE染色观察小鼠主动脉病理变化,全自动生化分析仪检测血脂水平,免疫组化检测主动脉C反应蛋白(CRP)、白细胞介素(IL)-6表达情况,16S rRNA测序检测盲肠内容物肠道菌群,液相色谱质谱联用(LC/MS)检测血清三甲胺(TMA)、氧化三甲胺(TMAO)水平,Western blot检测肝脏黄素单加氧酶3(FMO3)蛋白表达,RT-qPCR法检测肝脏FMO3 mRNA变化。结果空白对照组内膜平滑完整,胆碱对照组、ApoE^(-/-)对照组内膜增厚。与模型组比较,抗生素组和健脾化浊调脂方各剂量组斑块脂质沉积程度有所减轻,血脂水平明显改善,主动脉CRP、IL-6和血清TMA、TMAO以及肝脏FMO3 mRNA水平明显降低(P<0.05)。与模型组比较,抗生素组和健脾化浊调脂方中、高剂量组肝脏FMO3蛋白水平明显降低(P<0.01)。肠道菌群测序结果显示,与模型组比较,抗生素组肠道菌群丰度与多样性(Shannon、ACE、Chao1指数)明显降低,健脾化浊调脂方各剂量干预后,肠道菌群丰度与多样性明显升高(P<0.05)。在菌群门水平上,与模型组比较,经健脾化浊调脂方各剂量干预后,厚壁菌门、变形菌门比例明显下降,拟杆菌门比例明显升高。在菌群属水平上,经健脾化浊调脂方各剂量干预后,阿克曼氏菌属、乳杆菌属比例明显升高,葡萄球菌属比例明显下降。结论健脾化浊调脂方可能通过调节肠道菌群结构,抑制TMA/FMO3/TMAO通路,改善体内血清脂质水平,减轻炎症反应,从而延缓AS发生发展。 展开更多
关键词 健脾化浊调脂方 动脉粥样硬化 肠道菌群 tma/FMO3/tmaO通路
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MODELS OF ORE FORMING FOR BASE AND PRECIOUS DEPOSITS IN TECTONIC MAGMATIC ACTIVITY (TMA)REGIONS
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作者 GORZCHEVSKY D.I +1 位作者 KONSTANTINOV M.M 《Geotectonica et Metallogenia》 1994年第Z2期47-47,共1页
关键词 tma)regions MODELS OF ORE FORMING FOR BASE AND PRECIOUS DEPOSITS IN TECTONIC MAGMATIC ACTIVITY
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基于“心合小肠”探讨肠道菌群驱动TMA/FMO3/TMAO通路影响痰瘀互结证急性冠脉综合征大鼠血小板聚集的机制
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作者 张妮 陈彦熹 +1 位作者 李馨雅 陈韦 《中华中医药学刊》 北大核心 2025年第8期76-82,I0019-I0023,共12页
目的基于中医“心合小肠”理论探讨肠道菌群驱动TMA/FMO3/TMAO通路影响痰瘀互结证急性冠脉综合征(Acute coronary syndrome,ACS)大鼠血小板聚集的机制。方法45只SPF级健康SD大鼠,随机分为对照组(CON)、急性冠脉综合征组(ACS)、痰瘀互结... 目的基于中医“心合小肠”理论探讨肠道菌群驱动TMA/FMO3/TMAO通路影响痰瘀互结证急性冠脉综合征(Acute coronary syndrome,ACS)大鼠血小板聚集的机制。方法45只SPF级健康SD大鼠,随机分为对照组(CON)、急性冠脉综合征组(ACS)、痰瘀互结证急性冠脉综合征组(TYACS),每组15只。八通道多导心电图记录大鼠标准肢体Ⅱ导联心电图变化。全自动生化分析仪检测大鼠血清血脂水平。苏木素—伊红(Hematoxylin-eosin staining,HE)染色法观察大鼠心肌组织结构变化。光电比浊法检测血小板花生四稀酸(Arachidonic acid,AA)、二磷酸腺苷(Adenosine diphosphate,ADP)最大聚集率。LC/MS技术检测大鼠血浆三甲胺(Trimethylamine,TMA)、氧化三甲胺(Trimethylamine N-oxide,TMAO)含量,Realtime RT-PCR及Westernblot检测大鼠肝脏含黄素单氧化酶3(Flavin containing monooxygenase 3,FMO3)基因及蛋白表达。Spearman相关分析探讨TMAO与血小板AA、ADP最大聚集率的相关性。宏基因组技术检测大鼠肠道微生物组特征。结果ACS组及TYACS组大鼠心电图改变符合急性冠脉综合征,TYACS组大鼠血清血脂水平符合痰瘀互结证饮食不节改变。HE染色显示CON组大鼠心肌排列整齐、胞质丰富。ACS组及TYACS组大鼠缺血区炎症细胞浸润,心肌细胞核丢失,心肌细胞呈空泡样变,心肌组织紊乱。ACS组和TYACS组大鼠血小板AA和ADP最大聚集率均显著升高(P<0.01)。LC/MS技术检测发现ACS组大鼠TMA、TMAO含量均呈上升趋势。TYACS组大鼠TMA含量呈上升趋势,TMAO含量显著升高(P<0.001)。ACS组和TYACS组大鼠肝脏FMO3 mRNA及蛋白表达水平明显增高(P<0.01)。血小板AA、ADP最大聚集率与TMAO水平呈正相关。宏基因组技术发现ACS组和TYACS组大鼠肠道微生物组特征发生明显改变。CON组大鼠显著差异的物种标志物是拟杆菌门(Bacteroidetes),ACS组大鼠显著差异的物种标志物是厚壁菌门(Firmicutes)、梭杆菌门(Fusobacteria),TYACS组大鼠显著差异的物种标志物是变形杆菌门(Proteobacteria)、放线菌门(Actinobacteria)、螺旋体门(Spirochaetes)。KEGG富集分析发现痰瘀互结证ACS大鼠尤其以花生四烯酸代谢、核黄素的新陈代谢等通路富集的菌群最多,差异最明显。ACS大鼠尤其以花生四烯酸代谢、胰岛素抵抗和核黄素的新陈代谢等通路相关。结论痰瘀互结证ACS大鼠和ACS大鼠肠道微生物组发生显著特征性改变,模型大鼠血小板聚集过程可能与多种差异菌群共同驱动TMA/FMO3/TMAO通路,参与花生四烯酸代谢和核黄素的新陈代谢通路等有关。这一发现可能为探索通过调节菌群森林改善血小板聚集功能,预防ACS的新手段提供理论依据,丰富中医“心合小肠”理论。 展开更多
关键词 心合小肠 痰瘀互结证急性冠脉综合征 血小板聚集 肠道菌群 tma/FMO3/tmaO
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户内粉末涂料用非TMA 50/50环氧固化聚酯树脂性能研究
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作者 王佰佳 廖萍 《中国涂料》 2025年第6期64-69,共6页
利用刚性醇单体三羟甲基丙烷(TMP)复配柔性醇单体二甘醇(DEG)引入酯化醇,间苯二甲酸(PTA)与对苯二甲酸(PIA)复配作为酯化酸,PIA与己二酸(ADA)复配作为封端剂的方法,成功合成了一种透明非TMA50/50环氧固化聚酯树脂。实验固定封端剂中PIA... 利用刚性醇单体三羟甲基丙烷(TMP)复配柔性醇单体二甘醇(DEG)引入酯化醇,间苯二甲酸(PTA)与对苯二甲酸(PIA)复配作为酯化酸,PIA与己二酸(ADA)复配作为封端剂的方法,成功合成了一种透明非TMA50/50环氧固化聚酯树脂。实验固定封端剂中PIA与ADA复配比例,分别探讨了不同刚/柔醇单体比例、酯化酸复配比例以及不同醇酸比对于聚酯树脂理化指标及涂层性能的影响。结果表明:TMP/DEG在醇单体中质量份比为80/50时,利用PTA/PIA以700/427的质量份比进行复配作为酯化酸,PIA/ADA以质量份比为236/22进行复配作为封端剂,合成的聚酯树脂呈无色透明状态,T_(g)为61.19℃,粉末涂层的流平等级可达7级,常压水煮2 h保光率为90%,50 kg·cm正、反冲击均可通过。 展开更多
关键词 聚酯树脂 环氧树脂 tma 粉末涂料
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One tree,three major regions,and 700 fabric samples impress global buyers
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作者 Qiu Shuchen 《China Textile》 2025年第6期12-13,共2页
When the 2025 Intertextile Apparel Fabrics Exhibition(Autumn/Winter)was held in Shanghai,more than 3,700 top exhibitors from 26 countries and regions around the world participated.From September 2nd to 4th,the 2025&qu... When the 2025 Intertextile Apparel Fabrics Exhibition(Autumn/Winter)was held in Shanghai,more than 3,700 top exhibitors from 26 countries and regions around the world participated.From September 2nd to 4th,the 2025"Keqiao Selected"exhibition shone brightly at the event,showcasing the high-end quality of its products and the innovative strength of its regional brands. 展开更多
关键词 fabric samples autumn winter three major regions regional brands TREE shanghai exhibitors intertextile apparel fabrics exhibition
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Circular RNA signatures in vestibular migraine and migraine from cold regions:Preliminary mechanistic insights
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作者 Qihui Chen Jinghan Lin +2 位作者 Qingling Zhai Qijun Yu Yonghui Pan 《Frigid Zone Medicine》 2025年第4期193-205,共13页
Background:Vestibular migraine(VM)is a common disorder characterized by recurrent dizziness or vertigo,often aggravated by cold exposure.This study aimed to identify differentially expressed circular RNAs(circRNAs)in ... Background:Vestibular migraine(VM)is a common disorder characterized by recurrent dizziness or vertigo,often aggravated by cold exposure.This study aimed to identify differentially expressed circular RNAs(circRNAs)in cold-region VM and explore the underlying molecular mechanisms.Methods:Peripheral blood samples from long-term residents of Heilongjiang Province profiled by circRNA microarray,and differentially expressed circRNAs were validated by quantitative reverse transcription polymerase chain reaction(qRT-PCR).A competing endogenous RNA(ceRNA)network and enriched pathways were inferred by bioinformatics.A VM-like mouse model was established using nitroglycerin(NTG)and kainic acid(KA)and confirmed by behavioral testing and western blot.The hsa_circ_0003201/miR-31-5p/triggering receptor expressed on myeloid cells 2(TREM2)axis and related pathways were examined in clinical samples and in the trigeminal nucleus caudalis(TNC)and vestibular nuclei(VN)of mice using qRT-PCR,enzyme-linked immunosorbent assay(ELISA),and western blot.CircRNA microarray profiling also compared expression patterns between VM and migraine patients.Results:Hsa_circ_0003201 was significantly upregulated in cold-region VM patients.Bioinformatic analyses revealed that hsa_circ_0003201 may regulate the miR-31-5p/TREM2 axis and be associated with phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling,pyruvate metabolism,and transient receptor potential(TRP)pathways.Clinical validation confirmed increased hsa_circ_0003201 and TREM2 and decreased miR-31-5p.VM-like mice exhibited central sensitization and vestibular dysfunction,with increased TREM2,decreased miR-31-5p,and PI3K/AKT activation in the TNC and VN.Comparative circRNA analysis between VM and migraine patients indicated distinct expression patterns.Conclusion:Hsa_circ_0003201 shows potential as a diagnostic biomarker for cold-region VM,and the hsa_circ_0003201/miR-31-5p/TREM2 axis may contribute to pathogenesis through PI3K/AKT signaling,pyruvate metabolism,and TRP-related pathways. 展开更多
关键词 circRNA vestibular migraine cold regions
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PELSA:A novel method for highly sensitive identification of protein targets and binding regions
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作者 Jun Xiong Bi-Feng Yuan 《Chinese Chemical Letters》 2025年第12期3-4,共2页
Elucidation of ligand-protein interactions provides new insights into the physiological functions and mechanisms of ligand molecules,enabling new ideas for the treatment of diseases,and drug discovery and development.... Elucidation of ligand-protein interactions provides new insights into the physiological functions and mechanisms of ligand molecules,enabling new ideas for the treatment of diseases,and drug discovery and development.Most ligand-protein binding occurs only in specific regions of proteins.The identification of protein targets and binding regions is crucial for drug discovery and development,as well as for the in-depth study of drug-protein conformational relationships[1]. 展开更多
关键词 drug discovery ligand protein interactions ligand moleculesenabling drug development physiological functions binding regions identification protein targets binding regions protein targets
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Assessing waste classification in rural China:A framework for selecting pilot regions
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作者 CAO Chao-xue 《Ecological Economy》 2025年第3期228-243,共16页
Before nationwide implementation of waste classification programs in rural areas,identifying suitable pilot regions is crucial.This study develops a comprehensive framework for assessing and selecting these pilot regi... Before nationwide implementation of waste classification programs in rural areas,identifying suitable pilot regions is crucial.This study develops a comprehensive framework for assessing and selecting these pilot regions.Data were collected through 654 valid questionnaires and interviews with respondents from rural areas in six provinces across China.Primary assessment criteria included disposal methods for kitchen waste,recyclables,hazardous waste,and residual waste,as well as farmers’willingness to separate hazardous waste when offered compensation and the impact of centralized waste treatment in villages.Secondary criteria focused on disposal methods for agrochemical packages and other hazardous waste.Using the weighted sum of squares method,the study evaluated the suitability of six regions as pilot areas for waste classification.The results identified villages in Jiangsu province and Hebei province as the most suitable pilot regions.Based on the findings,the study provides recommendations to address weaknesses in these regions to enhance the effectiveness of future trials and offers tailored suggestions for other regions to improve their waste classification initiatives. 展开更多
关键词 ASSESSING waste classification rural China pilot regions
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Cryopreservation of bovine sperm causes single‑strand DNA breaks that are localized in the toroidal regions of chromatin
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作者 Jordi Ribas‑Maynou Rodrigo Muiño +1 位作者 Carolina Tamargo Marc Yeste 《Journal of Animal Science and Biotechnology》 2025年第1期92-106,共15页
Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial insemination.While freeze-th... Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial insemination.While freeze-thawing is known to impair sperm DNA integrity,whether the damage induced consists of single-(SSB)or double-strand breaks(DSB)has not been determined.In addition,no previous study has addressed if DNA breaks preferentially reside in specific genome regions such as those forming the toroid linker regions,or are rather spread throughout the regions linked to protamines.The main aim of the present work,therefore,was to elucidate the type and localization of the DNA damage generated by cryopreservation and to evaluate its impact on artificial insemination outcomes in cattle.Results The incidence of SSB and DSB was evaluated in 12 ejaculates before and after cryopreservation with the Comet assay,and the localization of the DNA breaks was assessed using pulsed-field gel electrophoresis(PFGE).Before cryopreservation,the incidence of SSB was 10.99%±4.62%and involved 20.56%±3.04%of sperm cells,whereas these figures significantly(P<0.0001)increased up to 34.11%±3.48%and 53.36%±11.00%in frozen-thawed sperm.In contrast,no significant differences in the incidence of DSB were observed(P>0.990)before and after cryopreservation(before:incidence of 13.91%±1.75%of sperm DNA affecting 56.04%±12.49%of sperm cells;after:incidence of 13.55%±1.55%of sperm DNA involving 53.36%±11.00%of sperm cells).Moreover,PFGE revealed that the percentage of sperm DNA fragments whose length was shorter than a toroid(<31.5 kb)was greater(P<0.0001)after(27.00%±4.26%)than before freeze-thawing(15.57%±4.53%).These differences indicated that the DNA breaks induced by cryopreservation affect the regions condensed in protamines,which are structured in toroids.On the other hand,in vivo fertility rates were associated to the incidence of SSB and DSB in frozen-thawed sperm(P=0.032 and P=0.005),but not with the size of the DNA fragments resulting from these breaks(P>0.05).Conclusion Cryopreservation of bovine sperm generates single-strand DNA breaks,which are mainly located in protamine-condensed toroidal regions.The incidence of DNA breaks in cryopreserved sperm has an impact on cat-tle fertility,regardless of the size of generated fragments. 展开更多
关键词 Cattle DNA damage Fertility SPERM Toroid linker regions
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Simulation of acoustic waves in 2D circular regions using the multi-block structured grid finite-difference method
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作者 Changjiang Fang Zhenguo Zhang +7 位作者 Hengxin Ren Heng Zhang Wenqiang Wang Zhaoyang Lu Qiwei Zhan Wei Zhang Qinghua Huang Xiaofei Chen 《Earthquake Science》 2025年第6期531-544,共14页
Global acoustic simulations are significant in revealing the internal and physical structure of the Earth.However,due to the limited flexibility of grids and the difficulties in handling boundaries,the traditional fin... Global acoustic simulations are significant in revealing the internal and physical structure of the Earth.However,due to the limited flexibility of grids and the difficulties in handling boundaries,the traditional finite-difference method(FDM)is usually less used in global simulations.Nevertheless,these issues can be well resolved by employing a multi-block structured grid to discretize circular regions.In this paper,we propose an O-H grid approach to partition the circular region and utilize the curvilinear grid finite-difference method(CGFDM)to solve the acoustic wave equation within this circular domain.By appropriately stretching the grid,the interconnections between each grid block are sufficiently smooth for stable information exchange.To verify the efficacy of this method,we conducted three numerical experiments,by comparing results with alternative approaches.Our test results demonstrate good agreement between our findings and the reference solutions.Since the proposed algorithm can effectively solve wave propagation problems in circular regions,it can contribute to 2D global simulation,particularly in interpreting the Earth’s interior. 展开更多
关键词 finite-difference method wave propagation multi-block grids circular region
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How do scientists use terminology related to cropland?Examining the disparity across disciplines and regions
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作者 Gehui Jin Yanbing Wei +1 位作者 Qiangyi Yu Wenbin Wu 《Journal of Integrative Agriculture》 2025年第12期4776-4786,共11页
In many existing dictionaries,cropland is defined as land that is suitable for or used to grow crops.It has several synonyms,such as“farmland”,“arable land”,and“cultivated land”.However,in scientific literature,... In many existing dictionaries,cropland is defined as land that is suitable for or used to grow crops.It has several synonyms,such as“farmland”,“arable land”,and“cultivated land”.However,in scientific literature,the nuances of these terms are often overlooked.The inconsistent terminology usage could lead to ambiguity and confusion in research and policy discussions.In particular,it creates difficulties for newcomers and students when they search for precise information in the published literature.Hence,exploring the variations of terminology applications is important for the cropland-related research community.In this study,the differences in six cropland-related terminologies were explored through a review of 5,214 scientific articles,by employing the independence test,clustering approach,and correlation analysis.The results showed that disparities exist across disciplines.For example,biodiversity&conservation studies preferentially use“farmland”to highlight effects from human activities,while studies in geology and computer science use“cropland”.The term“cultivated land”tends to be used in geography research for clear geographical demarcation,while“arable land”is related to engineering studies.Moreover,further disparities based on the geographical affiliations of the authors were found.The correlation between China and“cultivated land”was reliable and a close link was found between“agricultural land”and the USA.The regional variations in cropland terminology can be influenced by multiple factors,including the degree of agricultural mechanization,colonial history,and migration patterns.This study reveals variations in cropland-related terminology across disciplines and regions.The results highlight the importance of standardizing cropland terminology to foster interdisciplinary research,improve data comparability,and support global agricultural and environmental policymaking. 展开更多
关键词 cropland terminology discipline variation regional variation STANDARDIZATION agricultural research
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Effect of temperature and water content on surface albedo of loess in cold regions and the associated mechanisms
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作者 MA Anjing ZHANG Mingli +3 位作者 ZHOU Fengxi ZHOU Zhixiong FENG Wei WANG Zhen 《Journal of Mountain Science》 2025年第4期1306-1325,共20页
Surface albedo,as one of the important properties of the underlying surface,has a significant impact on the surface energy balance in cold regions.However,due to the complexity of the factors affecting surface albedo,... Surface albedo,as one of the important properties of the underlying surface,has a significant impact on the surface energy balance in cold regions.However,due to the complexity of the factors affecting surface albedo,existing calculations still contain inaccuracies.Therefore,this study conducted surface albedo experiments on loess with different water contents and temperatures.By analyzing the surface albedo measurements of samples with varying temperature and water content levels,as well as the soil freezing characteristic curve(SFCC)and soil-water characteristic curve(SWCC)of loess,the study explores the influence of soil temperature and water content on the surface albedo of loess.The results indicate that both the temperature and water content of loess jointly affect surface albedo.During the process of albedo change,there exists a water content threshold that alters the trend of surface albedo.Soil temperature influences surface albedo by affecting the content of pore ice and liquid water within the soil.When the water content of loess is relatively low,the surface albedo decreases as the unfrozen water content decreases.However,this trend changes as the water content of loess increases.Additionally,a decrease in soil temperature lowers the moisture content threshold during the changes in surface albedo.This study provides a reference for exploring and determining the surface energy balance in cold regions under the background of warm and humid climates,as well as for establishing thermal calculation boundaries. 展开更多
关键词 LOESS Cold regions Surface albedo Water content Soil temperature
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Untargeted metabolomics analysis of metabolite changes in gastric cancer patients from plateau regions
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作者 Ling-Hong Zhu Zhao-Xin Jin +6 位作者 Yan-Qing Ma Xiao Feng Cai-Hong Ci Yun-Song Zhou Qiao-Ling Gu Yong-Mei Lan Zi-Long Zhang 《World Journal of Gastrointestinal Oncology》 2025年第9期74-88,共15页
BACKGROUND Metabolomics sequencing technology was used to investigate the changes of intestinal flora and metabolites in gastric cancer patients in plateau areas.AIM To investigate changes in gut microbiota and their ... BACKGROUND Metabolomics sequencing technology was used to investigate the changes of intestinal flora and metabolites in gastric cancer patients in plateau areas.AIM To investigate changes in gut microbiota and their metabolites in patients with gastric cancer from plateau regions using untargeted metabolomic sequencing.METHODS Fresh morning fecal samples were collected from 30 gastric cancer patients diagnosed at a tertiary hospital in Qinghai Province and 30 healthy individuals(controls).Liquid chromatography-tandem mass spectrometry based untargeted metabolomic sequencing was used to analyze metabolite changes and predict metabolic function.RESULTS Metabolomic analysis identified 281 metabolites in samples from both groups.These metabolites were categorized into eight major classes,listed in descending order of abundance:Lipids and lipid-like molecules(35.443%);organic acids and derivatives(29.114%);organic oxygen compounds(15.19%);nucleosides,nucleotides,and analogs(13.924%);organoheterocyclic compounds(2.532%),amino acids and peptides(1.266%);benzenoids(1.266%);and fatty acids(1.266%).Compared with the control group,the top 10 metabolites elevated in the gastric cancer group included:Dethiobiotin,glycylproline,glycine,hydroxyisocaproic acid,tyramine,methionine sulfoxide,5-aminopentanoic acid,citrulline,betonicine,and formiminoglutamic acid and the top 10 decreased were:Cytidine,5'-methylthioadenosine,trehalose,melibiose,lotaustralin,adenosine,inosine,ribothymidine,raffinose,and galactinol.Functional prediction analysis revealed that these differential metabolites were primarily enriched in 12 metabolic pathways,including purine metabolism,cysteine and methionine metabolism,galactose metabolism,lysine degradation,glycine,serine,and threonine metabolism,biotin metabolism,pyrimidine metabolism,arginine and proline metabolism,histidine metabolism,primary bile acid biosynthesis,starch and sucrose metabolism,and tyrosine metabolism.CONCLUSION Significant differences in intestinal microbial metabolites and associated metabolic pathways were observed between gastric cancer patients and healthy controls residing in plateau regions. 展开更多
关键词 Plateau regions Gastric cancer Untargeted metabolomics METABOLITES Metabolic pathways
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Developing branch diameter and length models for the planted Larix kaempferi from different latitude regions in China
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作者 Yiwen Tong Dongsheng Chen +2 位作者 Huilin Gao Yunhui Xie Jiateng Liu 《Journal of Forestry Research》 2025年第5期160-174,共15页
Branch length and branch diameter are important characteristics that determine wood quality and yield.Development of static branch length and diameter models by incorporating individual tree variables,site quality and... Branch length and branch diameter are important characteristics that determine wood quality and yield.Development of static branch length and diameter models by incorporating individual tree variables,site quality and competition have been widely studied,while the climate effect has rarely been reported.In this study,mixed-effects climate-sensitive branch length and diameter models were developed based on 228 sample trees of Larix kaempferi from three latitude regions in China(approximate 42°N in Liaoning Province,33°N in Gansu Province,and 30°N in Hubei Province).Results revealed that diameter at breast height,and crown ratio,sum of the basal areas of trees larger than the subject trees,dominant tree height,mean warmest month temperature,and summer precipitation substantially improved branch length model.Diameter at breast height,and crown ratio,ratio of the sum of DBH in sample plot to the subject tree,dominant tree height,mean warmest month temperature,and spring precipitation significantly improved branch diameter model.Compared with base model,mean square error reduction of mixed-effects branch length and diameter models were 32.9%and 44.1%,respectively.The relative contributions of covariates to branch length model were tree size(59.1%),site quality(25.7%),competition(13.5%),and climate(1.7%),and branch diameter model were tree size(57.0%),competition(21.9%),site quality(18.3%),and climate(2.8%).Relative contributions of covariates on branch length and diameter models from different latitude regions were different.Effects of competition on branch length model in Liaoning and Hubei were larger than climate,whereas climate in Gansu was larger than competition.As for branch diameter model,competition in Liaoning was larger than site quality,whereas site quality in Hubei and Gansu was larger than competition.The present study strengthened the importance of considering climate variables in developing branch length and diameter model.It is desirable to disentangle the different sources of variations in affecting branch length and diameter from different latitude regions to reduce the uncertainty in predicting branch characteristics under the condition of climate changing. 展开更多
关键词 Branch characteristic model Latitude regions CLIMATE Competition index Larix kaempferi
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