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Accessibility and Homology bounded Strong Unstable Foliation for Anosov Diffeomorphisms on 3-torus

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Acta Mathematica Sinica,English Series 2017年第1期33卷 71-76页

作者： Yan REN shao bo gan Peng Fei ZHANG School of Mathematical Sciences Peking University Department of Mathematics and Statistics Universityof Massachusetts

We give three equivalent conditions for non-accessibility of an Anosov diffeomorphism on the 3-torus with a partially hyperbolic splitting. Since accessibility is an open property, this gives a negative answer to Hammerlindl＇s question about homology boundedness of strong unstable foliation. Keywords Partially hyperbolic, accessible, homology bounded

关键词： Partially hyperbolic accessible homology bounded

Geometric-like imaginarity:Quantification and state conversion

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 13-22页

作者： Meng-Li Guo bo Li shao-Ming Fei School of Science East China University of TechnologyNanchang 330006China School of Computer and Computing Science Hangzhou City University Hangzhou 310015China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

From the perspective of resource-theoretic approach,this study explores the quantification of imaginary in quantum *** propose a well defined measure of imaginarity,the geometric-like measure of *** with the usual geometric imaginarity measure,this geometric-like measure of imaginarity exhibits smaller decay difference under quantum noisy channels and higher *** applications,we show that both the optimal probability of state transformations from a pure state to an arbitrary mixed state via real operations,and the maximal probability of stochastic-approximate state transformations from a pure state to an arbitrary mixed state via real operations with a given fidelity f,are given by the geometric-like measure of imaginarity.

关键词： quantum resource theory imaginarity geometric-like channels state transformations

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元宇宙视域下的图书馆多模态知识流通范式

图书馆论坛 2025年第1期45卷 87-95页

作者：傅爱雯邵波南京大学信息管理学院南京大学图书馆

随着元宇宙图书馆发展,知识不断迭代、转化和重构,多模态知识被纳入知识服务过程。为避免知识冗余、信息不完备、信息价值缺失等知识发展弊端出现,文章梳理元宇宙图书馆和多模态知识流通发展现状,总结图书馆内数据流通问题,归纳元宇宙... 详细信息

随着元宇宙图书馆发展,知识不断迭代、转化和重构,多模态知识被纳入知识服务过程。为避免知识冗余、信息不完备、信息价值缺失等知识发展弊端出现,文章梳理元宇宙图书馆和多模态知识流通发展现状,总结图书馆内数据流通问题,归纳元宇宙知识流通范式建设原则,从知识关联、知识组织到知识服务三个角度构建元宇宙视域下图书馆多模态知识流通范式(AOS),试图改善元宇宙环境下知识服务运行机制,为元宇宙图书馆各实践模型提供底层知识流动范式,为数字技术赋能以图书馆为代表的知识情报领域工作提供借鉴。

关键词：元宇宙图书馆多模态知识流通范式

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东北典型盐碱湿地碳排放的水深临界阈值及其温度依赖性

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湖泊科学 2025年第1期37卷 159-170,I0015-I0017页

作者：李姝臻刘强甘罗扬武海涛王波北京师范大学环境学院水环境模拟国家重点实验室北京100875 北京师范大学环境学院教育部水沙科学重点实验室北京100875 中国科学院长春分院长春130022 吉林莫莫格国家级自然保护区白城137316

作为全球重要的碳库,湿地在缓解气候变化方面发挥了重要作用。然而在全球变暖背景下,湿地的碳排放(尤其是甲烷(CH_(4))排放)存在高度变异性和不确定性,极大地削弱了湿地碳库功能的发挥。为了探究不同水深梯度下东北盐碱湿地碳排放通量... 详细信息

作为全球重要的碳库,湿地在缓解气候变化方面发挥了重要作用。然而在全球变暖背景下,湿地的碳排放(尤其是甲烷(CH_(4))排放)存在高度变异性和不确定性,极大地削弱了湿地碳库功能的发挥。为了探究不同水深梯度下东北盐碱湿地碳排放通量的特征,本研究以莫莫格湿地为主要研究区,选取5种代表性植被(芦苇(Phragmites australis)、扁秆藨草(bolboschoenus planiculmis)、三江藨草(Schoenoplectus nipponicus)、香蒲(Typha orientalis ***)和碱蓬(Suaeda glauca)),布设Marsh Organ中型实验生态系统模拟不同水深生境,揭示CH_(4)和二氧化碳(CO_(2))排放通量变化及其环境影响因子。结果表明,莫莫格湿地-10~50 cm水深范围内5种代表性植被生长季CH_(4)排放通量范围为0.07~86.74 mg/(m^(2)·h),平均值为8.89 mg/(m^(2)·h),其主要环境影响因素为水深、气温和表层10 cm土壤含水量;在研究水深范围内,代表性植被生长季CO_(2)排放通量范围为10.59~1891.08 mg/(m^(2)·h),平均值为450.12 mg/(m^(2)·h),其主要环境影响因素为水深、气温和表层10 cm土壤含水量。不同植被对碳排放的贡献量有所差异,具体来说,芦苇和香蒲的CH_(4)排放通量最高,而藨草的CO_(2)排放通量最高。碳排放随水深变化呈现分段规律,CH_(4)排放随水深变化呈现先增加后减少的趋势,而CO_(2)则呈现相反规律,随水深变化先减小后增加,其水深临界阈值均出现在22 cm处。在不同水深范围内,CO_(2)排放对于水深的敏感性均大于CH_(4),且当水深大于22 cm时,CH_(4)和CO_(2)均呈现出更高的水深敏感性。碳排放在不同水深范围对温度的敏感程度不同,当水深小于22 cm时,CH_(4)和CO_(2)均呈现出更高的温度敏感性,然而当水深大于22 cm时,二者对温度均不敏感。结果表明升温背景下,东北典型盐碱湿地水陆过渡区关键生态系统在不同水深范围内呈现出不对称的响应模式,频繁的水位波动会极大地改变湿地碳排放格局,从而影响到湿地碳功能的稳定发挥。

关键词：碳排放水深温度依赖性莫莫格湿地阈值

Primary parenchymal squamous cell carcinoma of the kidney:A case report

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World Journal of Clinical Cases 2025年第4期13卷 34-40页

作者： Zhi-Hui Zheng bo shao Chao-Min Xu Ke Wang Jia-Zhu Wen Li-Kang Luo Jia-Cheng Guan Department of Ultrasound The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Radiology Shulan(Quzhou)HospitalQuzhou 324000Zhejiang ProvinceChina Department of Radiology The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Pathology The Second people’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina

BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases *** SUMMARY This study reports a 51-year-old man with primary SCC of the renal *** patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross *** antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated *** patient underwent laparoscopic unilateral nephrectomy and lymph node *** pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and *** pathological stage was *** months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena *** patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease *** We report a case of primary SCC of the renal parenchyma,a rare renal *** clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis *** to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.

关键词： Renal tumor Renal parenchyma Squamous cell carcinoma Renal calculi Computed tomography Case report

MIL-53(Fe、Al)/PSf共混膜的制备与性能研究

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现代化工 2025年第1期45卷 190-194页

作者：张梅李博甘磊尤涵博赵维雪东北石油大学化学化工学院黑龙江大庆163318

通过溶剂热法合成了双金属有机框架MIL-53(Fe、Al)亲水性材料,与聚砜(PSf)共混并通过非溶剂致相分离法制备MIL-53(Fe、Al)/PSf共混膜。探究了MIL-53(Fe、Al)的添加质量分数对共混膜的结构和亲水性、渗透性、截留性以及抗污染性能的影响... 详细信息

通过溶剂热法合成了双金属有机框架MIL-53(Fe、Al)亲水性材料,与聚砜(PSf)共混并通过非溶剂致相分离法制备MIL-53(Fe、Al)/PSf共混膜。探究了MIL-53(Fe、Al)的添加质量分数对共混膜的结构和亲水性、渗透性、截留性以及抗污染性能的影响。结果表明,当MIL-53(Fe、Al)的添加质量分数为0.3%时,与原膜相比,水接触角降低了28.81°,达到54.78°;纯水通量提高了10.21倍,达到179.15 L/(m^(2)·h·bar)。MIL-53(Fe、Al)的加入,显著提高了PSf超滤膜的亲水性和抗污染性能。

关键词：双金属有机框架聚砜共混膜亲水性抗污染性

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车辆荷载对黄土隧道作用标准值的计算与分析

公路 2025年第1期70卷 305-312页

作者：张博关少钰杨绍战中交第一公路勘察设计研究院有限公司西安市710075

结合北方某黄土隧道工程实例,深入研究车辆荷载作用下竖向土压传递和扩散变化规律,基于分布角法选取最不利轴重布置对多埋深、多路宽、多形式下车辆荷载进行分析,结合构件宽度对车辆荷载标准值进行优化修正,并建立标准轮压曲线、超小断... 详细信息

结合北方某黄土隧道工程实例,深入研究车辆荷载作用下竖向土压传递和扩散变化规律,基于分布角法选取最不利轴重布置对多埋深、多路宽、多形式下车辆荷载进行分析,结合构件宽度对车辆荷载标准值进行优化修正,并建立标准轮压曲线、超小断面轮压修正曲线以及隧道结构轮压修正曲线,对比轮压曲线标准值、超小断面轮压曲线修正值以及隧道结构轮压曲线修正值可知:隧道结构修正值<标准值<超小断面修正值。当传递深度大于2.8 m时,对任意下伏结构可统一考虑20 kPa地面超载,不再额外计算车辆荷载。对比分析结构跨度和重叠度对车辆荷载的影响,结果表明:竖向车辆荷载与结构宽度内最大并行车辆数呈正相关,当最大车辆并行数一定时,板跨越大,同深度下竖向车辆荷载越小,当下部结构宽度大于10 m后,竖向车辆荷载对板跨敏感性大大降低。对比同深度下隧道结构轮压修正曲线可知,竖向车辆荷载值随着重叠率的增大而显著增大,当重叠度低于20%时,可不额外计算车辆荷载,选取超载20 kPa,当重叠度为50%时,建议按照100%重叠度的一半取值。

关键词：黄土隧道车辆荷载浅覆土传递规律分布角法

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Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： Yi Wang Yuning Li Yakun Gu Wei Ma Yuying Guan Mengyuan Guo Qianqian shao Xunming Ji Jia Liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

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直接反射在线可视铁谱暗场显微成像特性分析

西安交通大学学报 2025年第2期59卷 189-200页

作者：李博袁勋尹智吴伟邵军马富银西安石油大学机械工程学院西安710065 西安交通大学机械工程学院西安710049

为评估直接反射在线可视铁谱(OLVF)暗场显微成像特性,提出了一种磨粒暗场显微成像模型。基于朗伯余弦和光后向散射理论建立了直接反射OLVF显微成像系统的反射光辐照度叠加模型,以实现磨粒暗场显微成像质量的定量评价;仿真计算互补金属... 详细信息

为评估直接反射在线可视铁谱(OLVF)暗场显微成像特性,提出了一种磨粒暗场显微成像模型。基于朗伯余弦和光后向散射理论建立了直接反射OLVF显微成像系统的反射光辐照度叠加模型,以实现磨粒暗场显微成像质量的定量评价;仿真计算互补金属氧化物半导体(CMOS)像面的反差透视比,分析了光学倍率、油液衰减系数和后向散射角变化对磨粒暗场显微成像清晰度的影响规律,确定了磨粒暗场显微成像的最优光学倍率为2.2和油液衰减系数大于2.0;明确CMOS像面的反差透视比在0.210~0.846范围内变化,直接反射OLVF可通过暗场显微成像获得较高清晰度的磨粒图像,其磨粒探测精度约为10μm。磨粒图像采集实验测试结果表明:直接反射OLVF暗场显微成像不仅能够从油液衰减系数大于2.28的原油、柴油机油中可靠捕获磨粒视觉信息,而且可从油液衰减系数小于2.0的液压油、齿轮油中获取磨粒谱片图像,解决了不同油液中金属磨粒探测问题,为在线监测采油装备磨损提供了可能性。

关键词：直接反射在线可视铁谱暗场显微成像反差透视比原油磨粒