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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou Wei-jin Jiang Ji Yu Mao-Jun Yao Yun-Tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(uRE),and ultrasonic assistance in boiling water extraction(uBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(Pultrasound-assisted extraction significantly increased the DMY content of the extracts(PuRE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in uRE and uBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,uRE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

High-resolution subsurface articular cartilage imaging based on Fourier-domain common-path optical coherence tomography

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Chinese Optics Letters 2010年第2期8卷 167-169页

作者： Jae-Ho Han Xuan Liu.jin u. Kang Chul Gyu Song Department of Electrical and Computer Engineering Johns Hopkins University 3400 N. Charles St. Baltimore MD 21218 USA Division of Electronics and Information Engineering Center for Advanced Image and Information Technology Chonbuk National University Deokjin-Dong Jeonju 561-756 Korea

We demonstrate the subsurface imaging of an articular cartilage using Fourier-domain common-path optical coherence tomography. The bare fiber probe integrated with a hypodermic needle provides the rigidness required to perform lateral scanning with less microscale bending. By submerging both the probe and the specimen into saline solution, we not only reduce the beam divergence, but also increase the signal-to-noise ratio compared with the measurement in free space. Our system can differentiate the characteristic cartilage zones and identity various micro-structured defects in an ex vivo chicken knee cartilage, thus demonstrating that it could be used to conduct early arthritis diagnosis and intraoperative endo-microscopy.

关键词： High-resolution subsurface articular cartilage imaging based on Fourier-domain common-path optical coherence tomography

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing Yang Si Liu YiHua He Chang Yang YuYue jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation(AKR)is a common radio emission,which can contribute to the magnetosphere−ionosphere−atmosphere *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500−4500 km and invariant latitude(|ILAT|)=60°−80°has been analyzed.63045 AKR samples have been identified with~48%(52%)samples on the dayside(nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05−08 and 18−22(02−05 and 12−17)in the northern(southern)*** distinct MLT asymmetry is associated with the direction of Bxof the interplanetary magnetic *** addition,the occurrence rate on the nightside clearly increases as the index *** study further enriches *** and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

Bending Stiffness of Concrete-Filled Steel Tube and Its Influence on Concrete Placement Timing of Composite Beam-String Structure

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Structural Durability & Health Monitoring 2025年第1期19卷 55-75页

作者： Zhenyu Zhang Quan jin Haitao Zhang Zhao Liu Yuyang Wu Longfei Zhang Renzhang Yan CCCC Third Highway Engineering Co. Ltd.Beijing101300China School of Civil Engineering Chongqing Jiaotong UniversityChongqing400074China

When the upper chord beam of the beam-string structure(BSS)is made of concrete-filled steel tube(CFST),its overall stiffness will change greatly with the construction of concrete placement,which will have an impact on the design of the tensioning plans and selection of control measures for the *** order to accurately obtain the bending stiffness of CFST beam and clarify its impact on the mechanical properties of composite BSS during construction,the influence of some factors such as height-width ratio,wall thickness of steel tube,elasticity modulus of concrete,and friction coefficient on the bending stiffness are analyzed parametrically by the numerical simulation technology based on an actual *** calculation formula of the equivalent bending stiffness of CFST is also established through mathematical statistical ***,the equivalent bending stiffness is introduced into the construction and use stages of the composite BSS,respectively,and the mechanical properties such as prestress-tensioning control value,structural deformation,and internal force of key members are comparatively analyzed when adopting two different construction ***,the optimal construction plan of concrete placement first and then prestress-tensioning is proposed.

关键词： Concrete panels freeze-thaw damage compression-shear crack tension-shear crack

Nanocarrier-mediated siRNA delivery:a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2538-2555页

作者： Jie jin Hu.jing Zhang Qianying Lu Linqiang Tian Sanqiao Yao Feng Lai Yangfan Liang Chuanchuan Liu Yujia Lu Sijia Tian Yanmei Zhao Wenjie Ren Institute of Disaster and Emergency Medicine Tianjin UniversityTianjinChina Key Laboratory for Disaster Medicine Technology TianjinChina Henan Medical Key Laboratory for Research of Trauma and Orthopedics The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina Clinical Medical Center of Tissue Engineering and Regeneration Xinxiang Medical UniversityXinxiangHenan ProvinceChina Institutes of Health Central Plain Xinxiang Medical UniversityXinxiangHenan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiangHenan ProvinceChina

Traumatic brain injury and Alzheimer's disease share pathological similarities,including neuronal loss,amyloid-βdeposition,tau hyperphosphorylation,blood-brain barrier dysfunction,neuroinflammation,and cognitive ***,traumatic brain injury can exacerbate Alzheimer's disease-like pathologies,potentially leading to the development of Alzheimer's *** offer a potential solution by facilitating the delive ry of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease.u nlike traditional approaches to neuro regeneration,this is a molecula r-targeted strategy,thus avoiding non-specific drug *** review focuses on the use of nanocarrier systems for the efficient and precise delive ry of siRNAs,discussing the advantages,challenges,and future *** principle,siRNAs have the potential to target all genes and non-targetable protein s,holding significant promise for treating various *** the various therapeutic approaches currently available for neurological diseases,siRNA gene silencing can precisely"turn off"the expression of any gene at the genetic level,thus radically inhibiting disease progression;however,a significant challenge lies in delivering siRNAs across the blood-brain *** have received increasing attention as an innovative drug delive ry tool fo r the treatment of brain *** are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier,targeted drug delivery,enhanced drug stability,and multifunctional *** use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective *** this strategy is still in the preclinical exploration stage,it is expected to achieve clinical translation in the future,creating a new field of molecular tar

关键词： blood-brain barrier cognitive dysfunction exosomes gene silencing immunotherapy inorganic nanomaterials liposome nanoparticles neuroinflammation polymer nanoparticles stem cells

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SnO高压结构稳定性和电学性能研究

光谱学与光谱分析 2025年第1期45卷 82-87页

作者：刘涛黄宇轩高金金王世霞上海理工大学材料与化学学院上海200093

近年来氧化亚锡(SnO)在光、电等方面的应用日益广泛,为了拓宽SnO的应用范围,采用拉曼光谱原位测试和第一性原理计算对高压条件下SnO的结构性能和电子性质进行研究。SnO表征结果:扫描电子显微镜结果显示,所选取SnO样品为具有横向尺寸的... 详细信息

近年来氧化亚锡(SnO)在光、电等方面的应用日益广泛,为了拓宽SnO的应用范围,采用拉曼光谱原位测试和第一性原理计算对高压条件下SnO的结构性能和电子性质进行研究。SnO表征结果:扫描电子显微镜结果显示,所选取SnO样品为具有横向尺寸的片状堆叠,整体呈花状;X射线衍射图谱表明,SnO样品在常温常压下晶体结构为四方晶系结构(空间群P4/nmm)。采用Mao-Bell型金刚石压腔结合原位拉曼光谱探究了SnO样品在高压下的结构性能变化,结果显示:SnO在常压有四种拉曼振动模式(A_(1g)、B_(1g)、E_(1g)和E_(2g)),分别位于211、350、113和460 cm^(-1)波数附近,其中113和211 cm^(-1)为SnO拉曼特征峰。随SnO样品体系加压至12.5 GPa,压力使Sn分子间和原子间距不断减小,导致Sn-O键长缩短,当原子发生伸缩振动时,缩短的键长使得键能增大,因此活性拉曼振动模(E_(1g)和A_(1g))均向高频方向移动;随着体系压力的继续增大,晶格发生畸变进而使得非弹性散射强度降低,峰型宽化;当加压至8 GPa时,125和216 cm^(-1)附近振动模峰急剧减小;加压至10 GPa时两个特征峰完全消失,在非静水压环境下8~10 GPa时该物质发生了非晶化;当体系加压至12.5 GPa时,谱图中仍未出现新峰,表明高压下非晶化状态稳定。随后体系进行卸压,卸压至3 GPa后SnO的E_(1g)和A_(1g)模重新出现表明样品恢复低压下的晶体结构,卸至常压特征峰强度明显分别为110和209 cm^(-1)处与加压前吻合,证明了SnO高压相变行为具有可逆性。为进一步了解压力对SnO电学性能影响,使用第一性原理方法计算了SnO在常压和实验非晶化压力(8 GPa)下的电子性质,通过非晶化前后SnO的带隙宽度变化,探究压力对SnO导电性能的影响。结果显示,在常压下SnO为具有0.43 eV带隙的间接带隙半导体,在费米能级附近态密度没有发生重叠,8 GPa时SnO显示金属性质,由于SnO O-p、Sn-s和Sn-p轨道的态密度在费米能级处重叠,导致带隙的闭合,材料发生金属化。研究结果表明SnO高压下可能产生非晶化及压力所导致的非晶化行为可逆,同时高压导致SnO发生半导体到金属的转变,拓展了SnO高压结构和电学性质的探究,为SnO高压下的应用提供进一步帮助。

关键词： SnO 拉曼光谱金刚石压腔第一性原理电子性质

Fiber-optic Fourier-domain common-path OCT

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Chinese Optics Letters 2008年第12期6卷 899-901页

作者： Xuan Liu Xiaolu Li Do-Hyun Kim Ilko Ilev jin u. Kang Department of Electrical and Computer Engineering Johns Hopkins University 3400 N. Charles Street Baltimore MD 21218 USA Center for Devices and Radiological Health FDA 10903 New Hampshire Avenue Silver Spring MD 20993-0002 USA

We experimentally and theoretically investigated the performance of a fiber-optic based Fourier-domain common-path optical coherence tomography （OCT）. The fiber-optic common-path OCT operated at the 840-nm center wavelength. The resolution of the system was 8.8 μm （in air） and the working depth using a bare fiber probe was approximately 1.5 mm. The signal-to-noise ratio （SNR） of the system was analyzed. OCT images obtained by the system were also presented.

关键词： Fast Fourier transforms Image display Light emitting diodes Multiple scattering Optical coherence tomography Optical devices

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu.jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

“寒门贵子”是“补偿”还是“选拔”出来的?——对两所精英大学2018—2023年高校专项计划招生的追踪研究

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华东师范大学学报（教育科学版） 2025年第1期43卷 113-126页

作者：金文旺柳夕浪北京师范大学中国教育与社会发展研究院北京100875 山东师范大学教育学部济南250014

高校专项计划是我国促进高质量教育公平、破解农村学生上好大学难而出台的一项入学机会补偿政策。综合运用描述性统计方法,本研究对两所精英大学2018—2023年间高校专项计划的选录情况进行了持续追踪研究。从初审、降分、录取人数的总... 详细信息

高校专项计划是我国促进高质量教育公平、破解农村学生上好大学难而出台的一项入学机会补偿政策。综合运用描述性统计方法,本研究对两所精英大学2018—2023年间高校专项计划的选录情况进行了持续追踪研究。从初审、降分、录取人数的总体规模及变化趋势看,近几年高校专项计划政策力度不断加大,越来越多的寒门子弟进入精英高校。同时,精英大学高校专项计划实际招生呈现“补偿不均,选拔有余”的鲜明特点,经济欠发达、教育发展水平薄弱省域的农村学生和学校在该计划中并未获得更多优质高校入学机会的补偿,一个重要原因在于他们在高校自主选拔和高考选拔中处于劣势。为此,应调整高校专项计划招生办法及相关政策,确立“补偿为主,兼顾选拔”的价值导向并切实付诸实践,推进“实质的公平”。

关键词：高校专项计划补偿选拔教育公平精英大学