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IMITATIO ALEXANDRI–THE IMAGE OF DRUSUS MINOR ON BRASS TOKENS OF THE MüNZKABINETT,STAATLICHE MUSEEN ZU BERLIN
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作者 Alexa Kuter 《Journal of Ancient Civilizations》 2016年第1期85-122,共38页
State of research: characteristics, function, and dating of Roman brass tokens Tokens (tesserae) formed part of everyday material culture of both Greeks and Romans.1 Made of wood, bone, clay, or metal, they facilit... State of research: characteristics, function, and dating of Roman brass tokens Tokens (tesserae) formed part of everyday material culture of both Greeks and Romans.1 Made of wood, bone, clay, or metal, they facilitated, for example, entry into the theatre, identification of soldiers, participation in political meetings, or the receipt of a special amount of grain.2 展开更多
关键词 令牌 亚历山大 黄铜 模仿 形象 柏林 组成部分 物质文化
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全球凋落物与微生物化学计量的差异及其对土壤有机质示踪的启示
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作者 牛宇晨 刘济 +2 位作者 李自民 张慧荟 陈骥 《生态学报》 北大核心 2026年第6期2965-2977,共13页
土壤有机质主要来源于微生物和凋落物,两者在碳(C)、氮(N)、磷(P)含量及其化学计量比上存在显著差异。这种差异为基于输入源差异性的生态化学计量学方法示踪土壤有机质提供了可行性。然而,当前缺乏一个全球范围内的微生物与凋落物化学... 土壤有机质主要来源于微生物和凋落物,两者在碳(C)、氮(N)、磷(P)含量及其化学计量比上存在显著差异。这种差异为基于输入源差异性的生态化学计量学方法示踪土壤有机质提供了可行性。然而,当前缺乏一个全球范围内的微生物与凋落物化学计量比数据库来支持这一方法的应用。通过全球整合分析,收集了4357条凋落物和3107条微生物的生态化学计量特征数据,涵盖森林、草地和农田生态系统。研究结果表明,全球凋落物的平均原子比为C∶N∶P=2880∶47∶1,而全球微生物的平均原子比为C∶N∶P=108∶7.3∶1。不同生态系统中,凋落物的化学计量比呈现显著差异,其中农田生态系统的凋落物C∶N比最高(77.5),草地生态系统的凋落物C∶P比最高(4148),而草地生态系统的凋落物N∶P比最高(64.8)。微生物的化学计量比在不同生态系统间也存在显著差异,森林生态系统的微生物C∶N比最高(19.9),森林生态系统的微生物C∶P比最高(131),草地生态系统的微生物N∶P比最高(8.7)。同时,在同一生态系统下,凋落物和微生物的化学计量比存在显著差异,这为利用两者化学计量比差异进行土壤有机质示踪提供了可行性和科学依据。 展开更多
关键词 生态化学计量 生态系统功能 养分循环 土壤养分 土壤碳
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Impacts as Triggers for Weather-Related Decision Making: Observations at the Berlin Fire Brigade Control and Dispatch Center 被引量:1
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作者 Thomas Kox Catharina Lüder 《International Journal of Disaster Risk Science》 SCIE CSCD 2021年第4期610-615,共6页
This article presents the results of a series of ethnographic observations at the Berlin fire brigade control and dispatch center during routine and severe weather situations.The weather-related challenges of a fire b... This article presents the results of a series of ethnographic observations at the Berlin fire brigade control and dispatch center during routine and severe weather situations.The weather-related challenges of a fire brigade lie between the anticipation of events and their potential consequences,and the ad hoc reactions to actual impacts of weather.The results show that decisions and actions related to high impact weather are not necessarily motivated by weather warnings alone.Instead,they are reactions to the experience of impacts,for example,an increased number of missions or emergency calls.Impacts are the main trigger for the decision making.Weather is one additional external factor that influences the operational capability of a fire brigade.While commanding officers in a fire brigade control and dispatch center experience weather primarily through technical equipment,verified by ground truth,observations showed that direct personal contact with the regional weather service and colleagues on the ground takes on a greater role in actual severe weather situations.The observations point to the need for increased interagency communication between the emergency services,the weather service,and other organizations to integrate weather information,impacts,and non-weather-related tasks into coherent weather-related decision making. 展开更多
关键词 Berlin Emergency services Fire brigades Impact-based emergency response Interagency communication Weather-related decision making
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评审感言
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作者 鲍里斯·沙德-宾索夫 尼可拉·博尔曼 +4 位作者 曹嘉明 胡越 蓝冰可 李存东 张悦 《世界建筑》 2026年第1期6-7,共2页
鲍里斯·沙德-宾索夫柏林《建筑世界》主编。我观察到一个极具说服力的趋势:建筑师正在普遍地对既有结构进行大胆的叠加。这种改造不再是修修补补,而是创造性覆盖——在旧肌理上生长出新的功能层级。这其中蕴含的未来乐观主义深深... 鲍里斯·沙德-宾索夫柏林《建筑世界》主编。我观察到一个极具说服力的趋势:建筑师正在普遍地对既有结构进行大胆的叠加。这种改造不再是修修补补,而是创造性覆盖——在旧肌理上生长出新的功能层级。这其中蕴含的未来乐观主义深深打动了我:那些曾经承载沉重记忆的旧空间,被转化为服务于年轻一代的、色彩斑斓的公共场所。通过灵活性重塑,让旧躯壳回应新问题,这种跨代际的对话能力,是当下建筑学最迷人的特质。 展开更多
关键词 创造性覆盖 未来乐观主义 建筑师 叠加
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阳宗海沉积物粒度端元揭示的末次冰消期以来水文气候与人类活动演变
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作者 李华勇 段立曾 +5 位作者 李华玉 祖奎红 孙启发 赵芳 Frank Riedel 张虎才 《地理科学》 北大核心 2026年第2期314-325,共12页
对采自云南阳宗海的沉积岩芯(YZH-1)进行AMS^(14)C测年,在建立可靠年代序列的基础上,分析钻孔粒度端元(end-member,EM)组分并探究其环境指示意义,恢复了区域13300 cal.a B.P.以来水文气候演化和人类活动。结果表明:EM1(5.0μm)与区域红... 对采自云南阳宗海的沉积岩芯(YZH-1)进行AMS^(14)C测年,在建立可靠年代序列的基础上,分析钻孔粒度端元(end-member,EM)组分并探究其环境指示意义,恢复了区域13300 cal.a B.P.以来水文气候演化和人类活动。结果表明:EM1(5.0μm)与区域红壤粒度特征相似,反映流域侵蚀强度;EM2(15.1μm)和EM3(30.2μm)反映湖泊水深,分别指示深湖相和浅湖相沉积。末次冰消期以来阳宗海水文气候和流域侵蚀演变过程可以分为5个阶段,阶段Ⅰ~Ⅳ[(13300—650) cal.a B.P.]阳宗海总体呈收缩趋势,与区域湿度变化规律一致;人类活动强度很低,流域侵蚀较弱,并具有先减小后增大特征,转折点出现在5500 cal.a B.P.前后,响应气候由暖湿向暖偏干转型。自1300年(阶段Ⅴ)以来EM1含量急剧升高,成为阳宗海沉积物的绝对优势粒度端元,反映快速增长的人口和农业规模破坏了植被,导致流域侵蚀加剧,与元朝1276年在西南边疆设“云南行中书省”,实行屯田制度,鼓励外省移民和农业生产的历史背景相吻合。自此,阳宗海流域环境的演变脱离了自然轨道,人类活动成为塑造地表景观、影响侵蚀强度的主要地质营力。 展开更多
关键词 阳宗海 全新世 粒度端元 环境演化 人类活动 流域侵蚀
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基于AERONET的喜马拉雅地区污染物气溶胶组成及时空变化研究
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作者 张傲楠 董志文 +2 位作者 李芳洲 焦晓瑜 江聪 《中国环境科学》 北大核心 2026年第2期618-626,共9页
本文建立了气溶胶5成分模型(黑碳BC、吸收性有机碳BrC、硫酸铵AS、粉尘DU和水分AW),利用AERONET数据对喜马拉雅山及周边地区的气溶胶组分进行了反演计算.结果显示:多年平均来看,各个站点成分柱质量浓度占比相似,其中AS、DU、AW、BrC和A... 本文建立了气溶胶5成分模型(黑碳BC、吸收性有机碳BrC、硫酸铵AS、粉尘DU和水分AW),利用AERONET数据对喜马拉雅山及周边地区的气溶胶组分进行了反演计算.结果显示:多年平均来看,各个站点成分柱质量浓度占比相似,其中AS、DU、AW、BrC和AW依次占比53.49%、29.33%、10.63%、5.27%、1.28%.同时,喜马拉雅山南坡地区的气溶胶柱质量浓度(年平均390mg/m^(2))显著高于北坡(年平均49mg/m^(2)),主要原因是高海拔山脉大量阻挡了南亚污染物气溶胶跨越喜马拉雅的传输(仅通过约13%).总体上,喜马拉雅地区春季(多年平均)气溶胶柱质量浓度最高,而夏,秋,冬季表现出大幅降低,这主要是由于春季季风前大气污染物排放的不断累积效应,以及南亚沙漠释放的粉尘气溶胶大量传输造成的,而在夏天季风期随着大量降水的淋洗而大量降低.年际变化来看,2015~2024期间的气溶胶平均柱质量浓度(南坡平均370.83mg/m^(2))略低于较早的2006~2015年期间(南坡平均453.26mg/m^(2)),这反映出南亚地区近期污染状况有所改善,然而总体大气污染状况仍然十分严重.由于黑碳和棕碳等吸收性气溶胶可以显著影响冰川积雪的加速消融,南亚地区持续的高污染气溶胶排放,预估未来会继续影响喜马拉雅山冰川变化. 展开更多
关键词 AERONET 气溶胶组分 喜马拉雅山 污染排放 时空变化
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Phase-field simulation of the dendrite fragmentation by electromagnetic stirring in AA5754 aluminum alloy laser beam welding
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作者 Chunliang Yang Fan Yang +3 位作者 Xiangmeng Meng Stephen Nugraha Putra Marcel Bachmann Michael Rethmeier 《China Welding》 2026年第1期57-68,共12页
A phase-field model including magnetic field induced dendrite fragmentation was established and applied to the cases with different initial crystal nuclear positions for AA5754 aluminum alloy electromagnetic laser bea... A phase-field model including magnetic field induced dendrite fragmentation was established and applied to the cases with different initial crystal nuclear positions for AA5754 aluminum alloy electromagnetic laser beam welding.Compare the calculated results that include dendrite fragmentation caused by the thermal electromagnetic Lorentz force with the results that consider only the thermal electromagnetic Lorentz force,without fragmentation,at the characteristic time instants.Both in the early and late stages,the small fragmentation at the dendrite tip promotes the number of higher-order branches and their growth,especially in the direction perpendicular to the solidification.The later stage fragmentation has the possibility of breaking one grain into several,which verifies the possibility of grain refinement caused by dendrite fragmentation.The fracture surface caused by fragmentation also makes more solid-liquid interfaces and their growth.In addition,the cases with different initial nuclear positions were compared.The grain growth in the low-temperature zone can be inhibited by the equiaxed grains'fragmentation at the high-temperature area(179.8μm^(2) and 14.7% start at the center,115.4μm^(2) and 9.4% start at the high-temperature corner,134.3μm^(2) and 10.9%start at the low-temperature corner),which is another kind of grain refinement by the dendrite fragmentation.This kind of inhibition effect on grain growth in the low-temperature region will be enhanced with the increasing time interval between the two crystal nuclei’appearance(179.8μm^(2) and 14.7%when virtual grains appear at t=4.3803 s and t=4.3803 s,134.3μm^(2) and 10.9%at t=4.0977 s and t=3.9564 s,and 115.4μm^(2) and 9.4%at t=3.8151 s and t=3.5325 s). 展开更多
关键词 Laser beam welding ELECTROMAGNETIC Aluminum alloys Phase field method Equiaxed grain Dendrite fragmentation
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论史前环南海文化的中华起源
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作者 郑漫 程志敏 《南海学刊》 2026年第2期61-68,共8页
综合考古学、历史语言学与群体遗传学成果,以南岛语族起源与扩展为线索,可界定出以南海周缘为核心,向太平洋与印度洋延展的“史前环南海文化带”及其外延传播通道。中国内地东南沿海-台湾走廊是该文化带形成与扩散中的关键枢纽。研究发... 综合考古学、历史语言学与群体遗传学成果,以南岛语族起源与扩展为线索,可界定出以南海周缘为核心,向太平洋与印度洋延展的“史前环南海文化带”及其外延传播通道。中国内地东南沿海-台湾走廊是该文化带形成与扩散中的关键枢纽。研究发现,中国台湾地区的物质文化与农业技术同福建、广东、广西等地的新石器传统呈现可追踪的连续性。南岛语族的“老家”在中国台湾,根系在华南,更深的文化底子则在长江-黄河流域。史前南方文明依托多点互动、跨海迁移与共享机制,在长时段与大空间尺度上受中华文明早期发展脉络的影响。环南海文明的核心要素及早期互联机制,为认识世界文明起源格局和人类社会共同体的史前生成基础提供了历史依据。 展开更多
关键词 南岛语族 史前环南海文化 中华起源 中国台湾地区 南方文化传播之路
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2025世界未来城市计划
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作者 鲍里斯·沙德-宾索夫 《世界建筑》 2026年第1期4-5,共2页
世界未来城市计划(IUPA)于2019年正式启动。自那时起,《世界建筑》期刊(北京)与《建筑世界》杂志(柏林)每年联合颁发该奖项,旨在表彰那些将建筑与城市规划真正融合、产生积极社会影响的杰出实践。没有建筑的城市发展是不可想象的;同样,... 世界未来城市计划(IUPA)于2019年正式启动。自那时起,《世界建筑》期刊(北京)与《建筑世界》杂志(柏林)每年联合颁发该奖项,旨在表彰那些将建筑与城市规划真正融合、产生积极社会影响的杰出实践。没有建筑的城市发展是不可想象的;同样,脱离了规划与设计语境的建筑,亦将沦为孤立的物体——一种悬浮于现实之外、缺乏意义的“不明飞行物”。城市规划是对建筑的组织与协调,它决定了城市的整体品质。这一认知已成为全球建筑师与城市规划师之间的普遍共识,并在全球宜居且繁荣的城市中得以具体呈现。正因如此,本奖项面向全球开放征集。 展开更多
关键词 世界建筑期刊 世界未来城市计划 建筑世界杂志
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石墨/陶瓷复合电阻材料的制备与性能
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作者 聂京凯 韩钰 +6 位作者 周明瑜 姬军 祝志祥 李阳林 马金旭 杜君莉 何强 《陶瓷学报》 北大核心 2026年第1期113-121,共9页
碳陶瓷电阻材料因具有导电性能良好、抗脉冲能力强、过载能力出色和散热能力强等优点,已成为国外高性能合闸电阻产品的主要材料。本文在分析国外某产品的基础上,以高纯度氧化铝和氧化硅为主要原料,以石墨为导电填料,设计并制备了一系列... 碳陶瓷电阻材料因具有导电性能良好、抗脉冲能力强、过载能力出色和散热能力强等优点,已成为国外高性能合闸电阻产品的主要材料。本文在分析国外某产品的基础上,以高纯度氧化铝和氧化硅为主要原料,以石墨为导电填料,设计并制备了一系列样品,并对其物相组成、气孔率、体积密度和电阻率进行了分析与测试。同时,实验结合分析测试结果,系统研究了氧化铝/氧化硅质量比、烧结助剂种类、石墨粒度及其加入量对样品物相组成和性能的影响。结果表明,与氧化铁相比,碳酸钙更有助于石英向方石英的晶型转变,并促进莫来石的生成。在氧化铝/氧化硅质量比为3∶1、添加3%碳酸钙为烧结助剂、掺入11%~15%的800目石墨为导电填料的条件下,可制得以刚玉、方石英、莫来石、石墨为主要物相的复合电阻材料,其开口气孔率为33.2%~35.5%、体积密度为1.99 g·cm^(-3)~2.10 g·cm^(-3)、电阻率为0.11Ω·m~4.66Ω·m。本文的研究结果有望为碳陶瓷复合电阻材料研究提供数据支撑。 展开更多
关键词 石墨 陶瓷 物相组成 电阻材料 电阻率
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“双减”背景下甘肃“影子教育”治理的现实挑战与破解路径
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作者 武宇轩 《陇东学院学报》 2026年第1期128-133,共6页
“双减”政策旨在减轻义务教育阶段学生过重的作业负担和校外培训负担,推动教育回归育人本质。以西部欠发达省份甘肃为研究对象,深入剖析了“双减”背景下其“影子教育”治理的现实困境与破解路径。研究发现,甘肃“影子教育”呈现出鲜... “双减”政策旨在减轻义务教育阶段学生过重的作业负担和校外培训负担,推动教育回归育人本质。以西部欠发达省份甘肃为研究对象,深入剖析了“双减”背景下其“影子教育”治理的现实困境与破解路径。研究发现,甘肃“影子教育”呈现出鲜明的城乡二元特征:城市地区隐形变异培训屡禁不止,而农村地区则充斥着师资薄弱、监管困难的家庭作坊式补课。治理挑战主要源于多元主体协同不足、监管政策执行存在偏差、技术手段滞后以及部分家长教育焦虑未消等复杂因素。对此,强化政府主导下的多元协同治理机制,完善契合地方实际的法律法规;运用数字技术提升对隐形变异形态的监管效能;深化教育综合改革,提升校内教育质量、均衡资源配置及加强家校共育,从源头上疏导社会对“影子教育”的过度需求。 展开更多
关键词 “影子教育” “双减”政策 教育治理
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A comparison of porous sandstone fracturing induced by increasing fluid pressure or decreasing confining pressure:Stress-path and rate-dependence effects
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作者 Xu Han Lei Wang +2 位作者 Erik Rybacki Marco Bohnhoff Georg Dresen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期151-165,共15页
When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may aff... When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may affect the initiation and propagation of fractures within brittle materials.Understanding the physical mechanisms leading to failure is crucial for underground engineering applications and geo-energy exploration and storage.We conducted triaxial compression experiments on porous Bentheim sandstone samples at different stress paths and pressure change rates.First,at a constant confining pressure of 35 MPa and pore pressure of 5 MPa,intact cylindrical samples were axially loaded up to about 85%of the peak strength.Subsequently,the axial piston position was fixed,and then either the pore pressure was increased or the confining pressure was decreased at two different rates(0.5 MPa/min or 2 MPa/min),leading to final catastrophic failure.The mechanical results revealed that samples subjected to higher rates of decreasing effective confining pressure exhibited larger stress drop rates,higher slip rates,higher total breakdown work,higher rates of acoustic emissions(AEs)before failure,and higher post-failure AE decay rates.In contrast,the applied stress path did not significantly affect rock failure characteristics.Comparison of located AE events with post-mortem microstructures of deformed samples shows a good agreement.The AE source type determined from the P-wave first-motion polarity shows that shear failure dominated the fracture process when approaching failure.Gutenberg-Richter b-values revealed a significant decrease before failure in all tests.Our results indicate that,in contrast to the stress path,the rate of effective stress change strongly affects fracturing behavior and AE rate changes. 展开更多
关键词 Porous sandstone Fluid injection Effective confining pressure changing rate Stress path
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Lysophosphatidic acid signaling:Transmembrane modulators in the central nervous system
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作者 Alexandra Polyzou Alexandros Κ.Tsiouris +2 位作者 Charalampos Labrakakis Britta J.Eickholt George Leondaritis 《Neural Regeneration Research》 2026年第3期1104-1105,共2页
Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,includi... Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018). 展开更多
关键词 transmembrane modulators cerebrospinal fluidvaries variety lipid species lysophosphatidic acid biological fluidsincluding lysophosphatidic acid lpa saturated unsaturated fatty acids pleiotropic lipid agonist
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Strain localization and time-dependent deformation in granodiorite characterized by distributed optical fiber sensing
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作者 Shuting Miao Arno Zang +3 位作者 Guido Blöcher Yinlin Ji Hannes Hofmann Pengzhi Pan 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期166-178,共13页
A multi-stage stress relaxation test was performed on a granodiorite sample to understand the deformation process prior to the macroscopic failure of brittle rocks,as well as the transient response during stress relax... A multi-stage stress relaxation test was performed on a granodiorite sample to understand the deformation process prior to the macroscopic failure of brittle rocks,as well as the transient response during stress relaxation.Distributed optical fiber sensing was used to measure strains across the sample surface by helically wrapping the single-mode fiber around the cylindrical sample.Close agreement was observed between the circumferential strains obtained from the optical fibers and the extensometer.The reconstructed full-field strain contours show strain heterogeneity from the crack closure phase,and the strains in the later deformation phase are dominantly localized within the former high-strain zone.The Gini coefficient was used to quantify the degree of strain localization and shows an initial increase during the crack closure phase,a decrease during the linear elastic phase,and a subsequent increase during the post-yielding phase.This behavior corresponds to a process of initial localization from an imperfect boundary condition,homogenization,and eventual relocalization prior to the macroscopic failure of the sample.The transient strain rate decay during the stress relaxation phase was quantified using the p-value in the“Omori-like"power law function.A higher initial stress at the onset of relaxation results in a lower p-value,indicating a slower strain rate decay.As the sample approaches macroscopic failure,the lowest p-value shifts from the most damaged zone to adjacent areas,suggesting stress redistribution or crack propagation in deformed crystalline rocks under stress relaxation conditions. 展开更多
关键词 Distributed optical fiber sensing Stress relaxation Strain localization Time-dependent deformation
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Monolithic Integration of Redox-Stable Sn-Pb Halide Perovskite Single-Crystalline Films for Durable Near-Infrared Photodetection
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作者 Rajendra Kumar Gunasekaran Jihoon Nam +9 位作者 Myeong-geun Choi Won Chang Choi Sunwoo Kim Doyun Im Yeonghun Yun Yun Hwa Hong Sang Hyeok Ryou Hyungwoo Lee Kwang Heo Sangwook Lee 《Nano-Micro Letters》 2026年第5期1-14,共14页
Tin-lead(Sn-Pb)halide perovskite single crystals combine narrow bandgaps,long carrier diffusion lengths,and low trap densities,positioning them as ideal candidates for near-infrared(NIR)optoelectronics.However,convent... Tin-lead(Sn-Pb)halide perovskite single crystals combine narrow bandgaps,long carrier diffusion lengths,and low trap densities,positioning them as ideal candidates for near-infrared(NIR)optoelectronics.However,conventional growth strategies rely on bulk crystallization at elevated temperatures,leading to uncontrolled nucleation,Sn^(2+)oxidation,and poor compatibility with planar integration.Here,we develop a coordination-engineered crystallization strategy that enables direct,lowtemperature growth of micrometer-thick Sn-Pb single-crystal thin films on device-compatible substrates.By modulating metal-solvent coordination strength using a low-donor number cosolvent system,we delineate a narrow processing window that stabilizes precursor speciation,lowers the nucleation barrier,and guides directional crystal growth under mild thermal conditions(<40℃).The resulting crystal films exhibit smooth morphology,high crystallinity,compositional uniformity,and ultralow trap densities(~3.98×10^(12)cm^(-3)).When integrated into NIR photodetectors,these films deliver high responsivity(0.51 A W^(-1)at 900 nm),specific detectivity up to 3.6×10^(12)Jones,fast response(~188μs),and>25,000 cycles of ambient operational stability.This approach establishes a scalable platform for redox-stable,low-temperature growth of Sn-Pb perovskite crystal films and expands the processing-structure-function landscape for next-generation infrared optoelectronics. 展开更多
关键词 Tin-lead perovskite Near-infrared photodetectors Single-crystal thin films Coordination chemistry Low-temperature crystallization
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The chicken gut microbiome in conventional and alternative production systems
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作者 Yu-Chieh Cheng Margret Krieger +1 位作者 Anna-Maria Korves Amélia Camarinha-Silva 《Journal of Animal Science and Biotechnology》 2026年第2期637-654,共18页
The poultry gut microbiome plays a key role in nutrient digestion,immune function,and overall health.Differences among various farming systems,including conventional,antibiotic-free,free-range,and organic systems,infl... The poultry gut microbiome plays a key role in nutrient digestion,immune function,and overall health.Differences among various farming systems,including conventional,antibiotic-free,free-range,and organic systems,influence microbial composition and function through variations in diet,genetic selection,environmental exposure,and antibiotic use.Conventional systems typically rely on formulated diets and controlled housing conditions,often with routine antimicrobial use.In contrast,organic systems emphasize natural feed ingredients,including roughage,outdoor access,and strict limitations on the use of antibiotics.These divergent practices shape the gut microbiota differently,with organic systems generally associated with greater exposure to environmental microbes and,consequently,greater microbial diversity.However,the implications of this increased diversity for poultry health and performance are complex,as organic systems may also carry a higher risk of pathogen exposure.This review summarizes current findings on the chicken gut microbiome across conventional and alternative production systems(antibiotic-free,freerange,and organic),focusing on microbial diversity,functional potential,and disease resilience.The need for standardized methodologies and consistent nomenclature in microbiome research is also discussed to improve comparability across studies.Understanding how production systems influence the gut microbiota is essential for improving poultry health and productivity while addressing challenges related to antimicrobial resistance and sustainable farming practices. 展开更多
关键词 Antimicrobial resistance CHICKEN Gut microbiome ORGANIC Production systems
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SNMR with short pulses:Optimizing the kernel calculation by considering the influence of pulse shape and phase
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作者 Tobias Splith Thomas Hiller +1 位作者 Stephan Costabel Mike Müller-Petke 《Magnetic Resonance Letters》 2026年第1期43-52,共10页
In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially satura... In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially saturated soils.The two limiting factors for the sensitivity are the dead time after the excitation pulse and the duration of the pulse itself.To enable short pulses,while also achieving proper depths of investigation,high pulse amplitudes are needed.This makes it necessary to consider the Bloch-Siegert effect,i.e.the counter-rotating component and the parallel component of the excitation field have significant influence on the excitation.If an untuned transmitter circuit is used,the pulse shape will also be non-sinusoidal.In this paper,we demonstrate that this influences SNMR measurements with short pulses in two ways:On one hand,the pulse shape influences the phase of the fundamental frequency oscillation.On the other,at very high pulse amplitudes,other frequency components of the excitation field start to influence the excitation.The behavior of the macroscopic magnetizations in the subsurface during the pulse is simulated by solving the Bloch equations,using the pulse shape as an input.Since these calculations are computational expensive,we propose a lookup scheme that allows a time efficient modeling of the obtained SNMR data. 展开更多
关键词 Surface NMR Pulse shape Numerical modeling Bloch-Siegert effect
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Performance Analysis of Bandwidth Aware Hybrid Powered 5G Cloud Radio Access Network
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作者 Md.Al-Hasan Mst.Rubina Aktar +3 位作者 Fahmid Al Farid Md.Shamim Anower Abu Saleh Musa Miah Md.Hezerul Abdul Karim 《Computers, Materials & Continua》 2026年第4期2146-2160,共15页
The rapid growth in available network bandwidth has directly contributed to an exponential increase in mobile data traffic,creating significant challenges for network energy consumption.Also,with the extraordinary gro... The rapid growth in available network bandwidth has directly contributed to an exponential increase in mobile data traffic,creating significant challenges for network energy consumption.Also,with the extraordinary growth of mobile communications,the data traffic has dramatically expanded,which has led to massive grid power consumption and incurred high operating expenditure(OPEX).However,the majority of current network designs struggle to efficientlymanage a massive amount of data using little power,which degrades energy efficiency performance.Thereby,it is necessary to have an efficient mechanism to reduce power consumption when processing large amounts of data in network data centers.Utilizing renewable energy sources to power the Cloud Radio Access Network(C-RAN)greatly reduces the need to purchase energy from the utility grid.In this paper,we propose a bandwidth-aware hybrid energypowered C-RAN that focuses on throughput and energy efficiency(EE)by lowering grid usage,aiming to enhance the EE.This paper examines the energy efficiency,spectral efficiency(SE),and average on-grid energy consumption,dealing with the major challenges of the temporal and spatial nature of traffic and renewable energy generation across various network setups.To assess the effectiveness of the suggested network by changing the transmission bandwidth,a comprehensive simulation has been conducted.The numerical findings support the efficacy of the suggested approach. 展开更多
关键词 5G BANDWIDTH renewable energy energy efficiency spectral efficiency C-RAN
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The satellite tracking of Great Snipes from European Russia reveals low migratory connectivity
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作者 Tatiana V.Sviridova Anna A.Bazhanova +1 位作者 Stepan M.Soloviev Christoph Zockler 《Avian Research》 2026年第1期46-58,共13页
Great Snipe(Gallinago media) is a shore bird which has a Near Threatened status on the global scale.However,little is known about its migration strategy from the breeding range in Russia.This study is the first one ai... Great Snipe(Gallinago media) is a shore bird which has a Near Threatened status on the global scale.However,little is known about its migration strategy from the breeding range in Russia.This study is the first one aiming to reveal migration routes,stopovers and wintering grounds of adult Great Snipes from their breeding range in Russia using GPS devices.We also analyzed connectivity of Great Snipes from different breeding populations of this species during non-breeding season.In 2021,we equipped seven males and three females with satellite transmitters,ICARUS Basic Tags,in the breeding range in central European Russia(56°75′N,37°65 E).One female appeared later in tundra of north-eastern Europe.In the second half of July to early September,birds migrated to Africa in a fairly wide front and made stopovers in Europe before crossing seas and the Sahara.Our data allowed to suppose high mortality of birds on migration,especially during the trans-Saharan flight.Only four Great Snipes reached Africa alive during southward migration.These birds spread over across wide area from Eritrea to Ghana after the trans-Saharan flight,after which they moved in a general westward direction and made final prolonged stopovers in Ghana or to the south of Chad Lake.In October/December birds relocated to wintering grounds in Sub-Equatorial Afrotropics as far as the south of Democratic Republic of the Congo and Zambia;with intermediate winter sites in low and middle reaches of the Congo Basin.Together with other published results,our data showed wide overlap of African non-breeding grounds of birds coming from lowland Eastern European and mountain Scandinavian breeding populations.The results also indicated insufficient conservation status of migration stopovers and wintering sites,used by Great Snipes,and demonstrated high importance of West Africa for conservation of this species. 展开更多
关键词 Geographical population Great Snipe ICARUS Basic Tags Migration mortality Satellite tracking Southward migration Wintering grounds
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Ligand- complex-based quantification of β2- integrin-mediated affinity and avidity of murine T cells
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作者 M.Therre A.A.Kuhnle +3 位作者 H.M.Arndt N.Frey M.H.Konstandin N.V.Bogert 《Animal Models and Experimental Medicine》 2026年第2期319-328,共10页
Background:Integrins facilitate binding to the extracellular matrix and other cells.Their subunit β2 is exclusively expressed by leukocytes,binds to the intercellular cell adhesion molecule 1(ICAM-1),and is pivotal f... Background:Integrins facilitate binding to the extracellular matrix and other cells.Their subunit β2 is exclusively expressed by leukocytes,binds to the intercellular cell adhesion molecule 1(ICAM-1),and is pivotal for their recruitment to sites of inflammation such as the atherosclerotic plaque.Methods:To investigate β2-integrin-mediated adhesiveness,a well-established assay for human whole blood was adapted for the analysis of murine T cell subsets.Changes in avidity and affinity were assessed by incubation of murine complexes ICAM-1 in murine whole blood and consecutive stimulation with PMA and Mg^(2+)/EGTA.Underlying signaling pathways in β2-integrin-mediated adhesiveness upon chemokine stimulation with CCL-19 were identified by incubation with reducing substances,and a Ca^(2+)chelator and ROS and Ca^(2+)measurements were carried out.Results:Incubation of murine whole blood with PMA leads to 30-fold and Mg^(2+)/EGTA to 65-fold increase in β2-integrin-mediated adhesiveness of T cells.Specificity of the assay was proven by preincubation of a blocking antibody,leading to a 60%reduction in adhesion capacity.ROS species and Ca^(2+)are crucial for chemokine-mediated β2-integrin activation.In vivo relevance was proven by induction of T cell adhesiveness in whole blood of mice upon myocardial infarction.Conclusions:Our assay allows specific quantification of β2-integrin-mediated affinity and avidity of T cells in whole blood samples.In congruence to human adhesion,these mechanisms are ROS and Ca^(2+)dependent and significantly elevated after myocardial infarction.Our refined and robust assay may be of particular use in phenotyping involved mechanisms in T cell activation in atherosclerotic cardiovascular disease. 展开更多
关键词 AFFINITY AVIDITY ICAM-1 T cells T helper cells β2-integrin
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