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Neuroprotective effects of Boswellia extract in animal models of ischemic stroke,Parkinson's disease,and Alzheimer's disease:a systematic review and meta-analysis
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作者 Meng-Ye Zhang Yu-Cheng Liao +7 位作者 Shan Liang Ji-Ping Yu Qian Meng Yi-Wen Wang Xing-F ang Zhang Wei Quan Ya-Jun Shi Yi Ding 《Traditional Medicine Research》 2026年第2期56-68,共13页
Background:Neurological disorders(NDs),including ischemic stroke(IS),Parkinson’s disease(PD),and Alzheimer’s disease(AD),are major contributors to global morbidity and mortality.Boswellia extract has demonstrated ne... Background:Neurological disorders(NDs),including ischemic stroke(IS),Parkinson’s disease(PD),and Alzheimer’s disease(AD),are major contributors to global morbidity and mortality.Boswellia extract has demonstrated neuroprotective properties,yet a comprehensive systematic review assessing its efficacy remains absent.This study aims to evaluate the efficacy of Boswellia extract in treating NDs,with a particular focus on its effects in AD and its potential for long-term neurorestoration,thereby supporting further investigation into Boswellia’s therapeutic role in ND management.Methods:A systematic literature search was performed in PubMed,Web of Science,ScienceDirect,and Google Scholar for English-language studies published up to March 2024.Eighteen studies met the inclusion criteria and were included in the meta-analysis.The study protocol was registered on PROSPERO(CRD42024524386).Eligible studies involved rodent models of IS,PD,or AD with post-operative interventions using Boswellia extract.Data extraction focused on mechanisms of action,dosages,treatment durations,and therapeutic outcomes.Studies were excluded if they involved non-ND models,combined treatments,or had incomplete data.Two researchers independently conducted literature screening and data extraction.Statistical analyses were conducted using Stata(version 17)and RevMan(version 5.4),employing fixed or random-effects models based on heterogeneity assessments.Result s:Boswellia extract significantly improved the mean effect size for NDs(ES=1.28,95%CI(1.05,1.51),P<0.001).Specifically,it reduced cerebral infarct volume in IS(SMD=−2.87,95%CI(−3.42,−2.32))and enhanced behavioral outcomes in AD(SMD=3.26,95%CI(2.07,5.14))and PD(SMD=5.37,95%CI(3.93,6.80)).Subgroup analyses revealed that Boswellia extract exhibited superior efficacy in AD when administered orally and via intra-cerebroventricular injection.Long-term treatment with Boswellia extract suggested potential neurorestorative effects.Additionally,Boswellia extract was more effective than its monomeric constituents,highlighting its promising role in ND treatment.Conclusion:Boswellia extract demonstrates significant neuroprotective effects across various NDs,particularly in AD and in promoting long-term neurorestoration.These findings support the need for further research into Boswellia’s potential as a therapeutic agent in the management of neurological disorders. 展开更多
关键词 Boswellic acid Boswellia extract ischemic stroke Parkinson’s disease Alzheimer’s disease META-ANALYsIs
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Short-chain fatty acids mediate enteric and central nervous system homeostasis in Parkinson’s disease:Innovative therapies and their translation 被引量:1
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作者 Shimin Pang Zhili Ren +1 位作者 Hui Ding Piu Chan 《Neural Regeneration Research》 2026年第3期938-956,共19页
Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’... Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease. 展开更多
关键词 ALPHA-sYNUCLEIN blood-brain barrier blood circulation central nervous system ENDOCRINE enteric nervous system glial cell gut-brain axis gut microbiota intestinal barrier neuron Parkinson’s disease short chain fatty acids vagus nerve
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积石山M_(S)6.2、乌什M_(S)7.1地震前后地电场变化特征研究
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作者 范莹莹 安张辉 +1 位作者 吴优 林毅 《地震工程学报》 北大核心 2026年第1期197-204,共8页
利用积石山M_(S)6.2地震和乌什M_(S)7.1地震震中周围的地电场台站观测数据,研究地震发生前后地电场能谱值变化。结果表明:(1)在积石山M_(S)6.2地震发生前,武胜驿、松山和平凉等台观测到地电场低频成分能谱值有显著增大的现象;(2)乌什M_(... 利用积石山M_(S)6.2地震和乌什M_(S)7.1地震震中周围的地电场台站观测数据,研究地震发生前后地电场能谱值变化。结果表明:(1)在积石山M_(S)6.2地震发生前,武胜驿、松山和平凉等台观测到地电场低频成分能谱值有显著增大的现象;(2)乌什M_(S)7.1地震发生前,乌什、温泉和乌鲁木齐等台均观测到地电场低频成分能谱值先增大后降低的明显变化;(3)初步分析认为,地震前地电场异常现象主要是由于震源孕育过程中激发的低频电磁辐射传播至台站所致。然而,测区地下介质的形变也可能激发局部区域的低频电磁辐射,这一因素同样不容忽视。 展开更多
关键词 积石山M_(s)6.2地震 乌什M_(s)7.1地震 地电场 能谱 变化特征
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2022年云南红河M_(S)5.0地震震源参数测定
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作者 李姣 姜金钟 +1 位作者 顾慧冬 叶泵 《地震研究》 北大核心 2026年第2期177-189,共13页
针对2022年云南红河M_(S)5.0地震震源深度测定结果存在显著差异的问题,基于云南地震台网记录的宽频带数字波形和区域一维速度模型,利用CAP方法反演了红河地震序列中M_(S)5.0和M_(S)3.5两次地震的震源机制解和最佳震源深度,然后采用sPL... 针对2022年云南红河M_(S)5.0地震震源深度测定结果存在显著差异的问题,基于云南地震台网记录的宽频带数字波形和区域一维速度模型,利用CAP方法反演了红河地震序列中M_(S)5.0和M_(S)3.5两次地震的震源机制解和最佳震源深度,然后采用sPL深度震相进一步测定其震源深度,最后综合震源深度、震源机制解和区域构造地质情况初步探讨了此次地震的发震机理。结果表明:2022年红河M_(S)5.0地震是以右旋走滑型为主、兼具少量逆冲分量的地震,最佳双力偶机制解为节面Ⅰ:33°/75°/18°,节面Ⅱ:298°/73°/164°,震源深度为3~4 km;M_(S)3.5地震最佳双力偶机制解为节面Ⅰ:31°/83°/7°,节面Ⅱ:300°/83°/173°,震源深度为7~8 km。综合此次M_(S)5.0主震震源深度较浅,以及红河断裂带南段断层构造相对北段较为简单等因素,初步分析认为是上地壳断层浅部区域应力积累导致M_(S)5.0主震的发生,主震后的应力调整导致了较深处的M_(S)3.5余震的发生,同时,由于震源区断层构造较为平直简单、应力积累区域较为集中,两次较大地震发生后余震很少。 展开更多
关键词 红河M_(s)5.0地震 震源深度 震源机制解 sPL震相 构造意义
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基于改进YOLOv5s的水稻秸秆量识别检测方法
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作者 葛宜元 孙修涵 +3 位作者 孟庆祥 梁秋艳 马浏轩 杜爽 《农机化研究》 北大核心 2026年第2期116-123,共8页
水稻秸秆腐解周期是衡量秸秆还田效果的重要指标。为提升水稻秸秆腐解效果,准确测量留于田间的秸秆量,将水稻收割后的田间秸秆状态分为铺放于田间的堆叠秸秆和根茎留于原位的留茬秸秆两种,并提出了一种基于改进YOLOv5s的水稻秸秆量识别... 水稻秸秆腐解周期是衡量秸秆还田效果的重要指标。为提升水稻秸秆腐解效果,准确测量留于田间的秸秆量,将水稻收割后的田间秸秆状态分为铺放于田间的堆叠秸秆和根茎留于原位的留茬秸秆两种,并提出了一种基于改进YOLOv5s的水稻秸秆量识别算法。采用色彩追踪算法结合HSV模型,对堆叠秸秆量进行检测;通过深度学习算法、OpenCV算法结合HSV模型和注意力模块,对留茬秸秆进行检测;引入CBAM注意力模块,同时通过非极大值抑制去除重叠锚定框,以消除重复计数的影响,从而实现对秸秆量的精准检测。通过训练模块对2174张水稻秸秆图片进行深度学习,识别精确率可达92.092%,召回率为96.144%,目标检测损失值为2.397%。实际田间秸秆检测时,正确检出率可达85.85%。改进后的算法可有效检出留茬秸秆并通过串口返回秸秆数量,为秸秆腐解剂的精量施放和还田模式的建立提供更为精确的数据支持。 展开更多
关键词 水稻秸秆量识别 改进YOLOv5s 注意力机制 图像处理 非极大值抑制
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S31608奥氏体不锈钢换热器腐蚀泄漏原因
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作者 吕渊 《理化检验(物理分册)》 2026年第1期42-45,50,共5页
某换热器发生泄漏,采用宏观观察、化学成分分析、扫描电镜和能谱分析、X射线衍射分析、金相检验等方法对泄漏原因进行分析。结果表明:换热器管程或壳程中的氯硅烷介质发生水解,生成了具有腐蚀性的氯离子,导致壳体内壁与管道在腐蚀性介... 某换热器发生泄漏,采用宏观观察、化学成分分析、扫描电镜和能谱分析、X射线衍射分析、金相检验等方法对泄漏原因进行分析。结果表明:换热器管程或壳程中的氯硅烷介质发生水解,生成了具有腐蚀性的氯离子,导致壳体内壁与管道在腐蚀性介质、工作应力及焊接残余应力的共同作用下发生应力腐蚀开裂,最终引起管道泄漏。 展开更多
关键词 换热器 s31608奥氏体不锈钢 应力腐蚀 残余应力 泄漏
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S100止血绫对TURP手术患者止血及促进创面愈合的效果分析
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作者 何綦琪 《首都食品与医药》 2026年第1期46-48,共3页
目的观察S100止血绫对经尿道前列腺电切术(TURP)的效果。方法选取186例患者进行研究,选取时间在2024年1月-2025年1月之间,均为在我院进行经尿道前列腺电切术(TURP)的患者。采用随机数表法对患者进行分组,每组93例,分别为对照组、实验组... 目的观察S100止血绫对经尿道前列腺电切术(TURP)的效果。方法选取186例患者进行研究,选取时间在2024年1月-2025年1月之间,均为在我院进行经尿道前列腺电切术(TURP)的患者。采用随机数表法对患者进行分组,每组93例,分别为对照组、实验组,对照组采用的方法为常规止血,实验组采用的止血方法为S100止血绫,比较两组患者的止血时间、住院时间和并发症等相关数据。结果应用S100止血绫的实验组患者在止血时间、引流管拔除时间、住院时间等方面均优于应用传统止血材料的患者,数据之间对比有统计学意义(P<0.05)。对照组并发症发生率高于实验组,数据对比,有统计学意义(P<0.05)。结论S100止血绫在经尿道前列腺电切术中止血效果良好,值得在临床中广泛推广和应用。 展开更多
关键词 s100止血绫 经尿道前列腺电切术 止血 分析 效果
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血清分形趋化因子、S100钙结合蛋白A8与老年重症肺炎合并呼吸衰竭患者预后的关系
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作者 王莉 沈德栋 《中国临床医生杂志》 2026年第1期40-43,共4页
目的探讨血清分形趋化因子(FKN)、S100钙结合蛋白A8(S100A8)与老年重症肺炎(SP)合并呼吸衰竭患者预后的相关性。方法前瞻性选取2022年6月至2024年6月在中国医科大学附属盛京医院进行治疗的老年SP合并呼吸衰竭患者104例为研究对象,根据... 目的探讨血清分形趋化因子(FKN)、S100钙结合蛋白A8(S100A8)与老年重症肺炎(SP)合并呼吸衰竭患者预后的相关性。方法前瞻性选取2022年6月至2024年6月在中国医科大学附属盛京医院进行治疗的老年SP合并呼吸衰竭患者104例为研究对象,根据预后分为存活组(n=81)和死亡组(n=23)。酶联免疫吸附试验检测患者血清FKN、S100A8水平;利用Cox回归模型评估患者预后的影响因素;构建受试者操作特征(ROC)曲线评估预测患者预后准确性。结果死亡组急性生理学和慢性健康状况评价Ⅱ评分、血清C反应蛋白、降钙素原及血清FKN、S100A8水平均高于存活组(P<0.05),上述指标升高均是影响患者死亡的危险因素(P<0.05)。血清FKN、S100A8联合预测患者预后的曲线下面积优于二者单独检测(Z_(联合-FKN)=2.767,Z_(联合-S100A)=2.029,P<0.05)。结论老年SP合并呼吸衰竭患者血清FKN、S100A8表达水平上升,二者联合预测在患者预后方面具有更高的价值。 展开更多
关键词 重症肺炎 呼吸衰竭 分形趋化因子 s100钙结合蛋白A8 预后
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2021年青海玛多M_(S)7.4地震震后余滑有限元数值模拟
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作者 魏巍 谭凯 +3 位作者 熊维 鲁小飞 张彩红 李承涛 《地震研究》 北大核心 2026年第1期92-99,共8页
2021年青海玛多发生的M_(S)7.4地震,是近30年来巴颜喀拉块体内唯一的1次强地震,震后形变显著,对区域构造运动和地震活动有很大的影响。采用速率强化摩擦准则的应力驱动余滑模型,建立玛多M_(S)7.4地震断层的三维有限元网格模型,以震后6个... 2021年青海玛多发生的M_(S)7.4地震,是近30年来巴颜喀拉块体内唯一的1次强地震,震后形变显著,对区域构造运动和地震活动有很大的影响。采用速率强化摩擦准则的应力驱动余滑模型,建立玛多M_(S)7.4地震断层的三维有限元网格模型,以震后6个月GPS形变资料为约束,研究震后形变的动力学参数。首先计算玛多M_(S)7.4地震断层的同震剪切应力,以此作为震后余滑的驱动源,正演震后余滑,探究震后断层最佳参考滑动速率和摩擦参数。结果表明:余滑与同震破裂在空间分布上有一定的互补关系,余滑主要集中在同震滑动的下倾区域,10~20 km深度范围内的余滑约占震后余滑总量的80%,最大滑动量达到1.1 m。最佳参考滑动速率V_(0)=400 mm/a,摩擦本构参数aσ=0.4 MPa。 展开更多
关键词 玛多M_(s)7.4地震 震后余滑 应力驱动 有限元数值模拟
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基于图像信息算法的2024年新疆乌什M_(S)7.1地震回溯性预测研究
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作者 袁伏全 黄浩 +2 位作者 徐玮阳 张晓清 刘兴盛 《地震研究》 北大核心 2026年第2期198-206,共9页
使用1970年以来新疆天山地震带及邻区的地震目录资料,基于图像信息(PI)算法,计算得到2016—2028年该地区逐年滑动的预测窗PI热点分布图像,并使用工作特征图表法(ROC)和R值评分法对PI算法的预测效能进行了检验。结果表明:①在2020—2024... 使用1970年以来新疆天山地震带及邻区的地震目录资料,基于图像信息(PI)算法,计算得到2016—2028年该地区逐年滑动的预测窗PI热点分布图像,并使用工作特征图表法(ROC)和R值评分法对PI算法的预测效能进行了检验。结果表明:①在2020—2024年回溯性预测图像中,2024年新疆乌什M_(S)7.1地震震中区域存在PI热点,具有较强的发震地点指示意义。②在5个回溯性预测时间窗(2016—2020年、2017—2021年、2018—2022年、2019—2023年、2020—2024年)内的PI热点图像演化过程中,乌什M_(S)7.1地震震中附近PI热点表现为“出现—逐步密集增强”,发震概率增大,该热点附近发震紧迫性和地震危险性增强。③ROC检验和R值评分显示,PI算法优于随机预测方法。④综合热点信息演化图像分析得到,南天山地震带的西南端强震危险性较高。 展开更多
关键词 乌什M_(s)7.1地震 PI算法 回溯性预测 地震热点 ROC检验
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Hyperspectral Image Reconstruction for Interferometric Spectral Imaging System with Degradation Synthesis
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作者 Yuansheng Li Xiangpeng Feng +2 位作者 Siyuan Li Geng Zhang Ying Fu 《Journal of Beijing Institute of Technology》 2025年第1期42-56,共15页
Among hyperspectral imaging technologies, interferometric spectral imaging is widely used in remote sening due to advantages of large luminous flux and high resolution. However, with complicated mechanism, interferome... Among hyperspectral imaging technologies, interferometric spectral imaging is widely used in remote sening due to advantages of large luminous flux and high resolution. However, with complicated mechanism, interferometric imaging faces the impact of multi-stage degradation. Most exsiting interferometric spectrum reconstruction methods are based on tradition model-based framework with multiple steps, showing poor efficiency and restricted performance. Thus, we propose an interferometric spectrum reconstruction method based on degradation synthesis and deep learning.Firstly, based on imaging mechanism, we proposed an mathematical model of interferometric imaging to analyse the degradation components as noises and trends during imaging. The model consists of three stages, namely instrument degradation, sensing degradation, and signal-independent degradation process. Then, we designed calibration-based method to estimate parameters in the model, of which the results are used for synthesizing realistic dataset for learning-based algorithms.In addition, we proposed a dual-stage interferogram spectrum reconstruction framework, which supports pre-training and integration of denoising DNNs. Experiments exhibits the reliability of our degradation model and synthesized data, and the effectiveness of the proposed reconstruction method. 展开更多
关键词 hyperspectral imaging degradation modeling data synthesis spectral reconstruction
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Three-dimensional measurement enabled by single-layer all-in-one transmitting-receipting optical metasystem
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作者 Xiaoli Jing Qiming Liao +5 位作者 Misheng Liang Bo Wang Junjie Li Yongtian Wang Rui You Lingling Huang 《Opto-Electronic Advances》 2025年第6期17-25,共9页
Optical three-dimensional(3D)measurement is a critical tool in micro-nano manufacturing,the automotive industry,and medical technology due to its nondestructive nature,high precision,and sensitivity.However,passive li... Optical three-dimensional(3D)measurement is a critical tool in micro-nano manufacturing,the automotive industry,and medical technology due to its nondestructive nature,high precision,and sensitivity.However,passive light field system still requires a refractive primary lens to collect light of the scene,and structured light can not work well with the highly refractive object.Meta-optics,known for being lightweight,compact,and easily integrable,has enabled advancements in passive metalens-array light fields and active structured light techniques.Here,we propose and experimentally validate a novel 3D measurement metasystem.It features a transmitting metasurface generating chromatic line focuses as depth markers and a symmetrically arranged receiving metasurface collecting depth-dependent spectral responses.A lightweight,physically interpretable algorithm processes these data to yield high-precision depth information efficiently.Experiments on metallic and wafer materials demonstrate a depth accuracy of±20μm and lateral accuracy of±10μm.This single-layer optical metasystem,characterized by simplicity,micro-level accuracy,easy installation and scalability,shows potential for diverse applications,including process control,surface morphology analysis,and production measurement. 展开更多
关键词 metasystem 3D reconstruction dispersion engineering
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A Structural Dynamic Response Reconstruction Method for Continuous System Based on Kalman Filter
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作者 LI Hongqiu JIANG Jinhui MOHAMED M Shadi 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第2期250-260,共11页
The structural dynamic response reconstruction technology can extract unmeasured information from limited measured data,significantly impacting vibration control,load identification,parameter identification,fault diag... The structural dynamic response reconstruction technology can extract unmeasured information from limited measured data,significantly impacting vibration control,load identification,parameter identification,fault diagnosis,and related fields.This paper proposes a dynamic response reconstruction method based on the Kalman filter,which simultaneously identifies external excitation and reconstructs dynamic responses at unmeasured positions.The weighted least squares method determines the load weighting matrix for excitation identification,while the minimum variance unbiased estimation determines the Kalman filter gain.The excitation prediction Kalman filter is constructed through time,excitation,and measurement updates.Subsequently,the response at the target point is reconstructed using the state vector,observation matrix,and excitation influence matrix obtained through the excitation prediction Kalman filter algorithm.An algorithm for reconstructing responses in continuous system using the excitation prediction Kalman filtering algorithm in modal space is derived.The proposed structural dynamic response reconstruction method evaluates the response reconstruction and the load identification performance under various load types and errors through simulation examples.Results demonstrate the accurate excitation identification under different load conditions and simultaneous reconstruction of target point responses,verifying the feasibility and reliability of the proposed method. 展开更多
关键词 dynamic load identification structural response reconstruction excitation identification Kalman filter continuous system
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The Measurement of Volume and Surface Area of the Middle Ear Pneumatic System and Its Clinical Significance
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作者 Wendi Zhang Xu Bie Shen Yu 《Journal of Otology》 2025年第3期185-189,共5页
Background The middle ear pneumatic system(MEPS)supports pressure balance,essential for sound conduction.Its volume and surface area are key indicators of pneumatization and ventilation,yet their specific contribution... Background The middle ear pneumatic system(MEPS)supports pressure balance,essential for sound conduction.Its volume and surface area are key indicators of pneumatization and ventilation,yet their specific contributions to pressure regulation need further exploration.Objective To evaluate the accuracy and sensitivity of parameters characterizing the MEPS,including volume(V),surface area(S),and surface-area-to-volume ratio(S/V),in normal ears.Materials and Methods We collected CT images of the temporal bone from 63 normal ears for this study.The volume(V),surface area(S),and surface-area-to-volume ratio(S/V)of the MEPS were measured and calculated using three-dimensional reconstruction technology.Statistical methods were used to process the data and determine the 95%reference range for the S,V,and S/V of the MEPS in the normal ear.At the same time,we analyzed the impact of differences in gender and the left and right sides on the measurements.Results The 95%reference values for the S,V,and S/V of the MEPS in normal ears were 1057.10~18239.16 mm²,609.16~9854.11 mm^(3),and 1.39~2.52 mm^(-1) respectively.There were no significant differences in the measurements between genders and between the left and right sides.Conclusions and Significance This study has established the 95%reference values for the S,V,and S/V of the MEPS in normal ears,which were 1057.10-18239.16 mm²,609.16-9854.11 mm^(3),and 1.39-2.52 mm^(-1) respectively.We found that while there is a wide variation in the V values among normal ears,there is less variability in the S/V values.This structural characteristic suggests that changes in the S/V value may have a more significant impact on the balance of middle ear pressure,and it provides important reference data for the construction and functional reconstruction of three-dimensional models of the MEPS.These findings may aid in diagnosing middle ear disorders,such as otitis media with effusion,and guide interventions to restore pressure balance. 展开更多
关键词 Middle Ear Pneumatic system Three-Dimensional Reconstruction surface Area-to-Volume Ratio
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Interference Suppression Based on Angular Reciprocity and Covariance Matrix Reconstruction in Satellite Communication Systems
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作者 Luo Jie Fan Jiancun +2 位作者 Liu Hongji Luo Xinmin Jiao Libin 《China Communications》 2025年第11期40-49,共10页
Satellite communication plays an important role in 6G systems.However,satellite communication systems are more susceptible to intentional or unintentional interference signals than other communication systems because ... Satellite communication plays an important role in 6G systems.However,satellite communication systems are more susceptible to intentional or unintentional interference signals than other communication systems because of their working mechanism of transparent forwarding.For the purpose of eliminating the influence of interference,this paper develops an angle reciprocal interference suppression scheme based on the reconstruction of interferenceplus-noise covariance matrix(ARIS-RIN).Firstly,we utilize the reciprocity between the known beam central angle and the unknown signal arrival angle to estimate the angle of arrival(AOA)of desired signal due to the multi-beam coverage.Then,according to the priori known spatial spectrum distribution,the interferenceplus-noise covariance matrix(INCM)is reconstructed by integrating within the range except the direction of desired signal.In order to correct the estimation bias of the first two steps,the worst-case performance optimization technology is adopted in the process of solving the beamforming vector.Numerical simulation results show that the developed scheme:1)has a higher output signal-to-interference-plus-noise ratio(SINR)under arbitrary signal-to-noise ratio(SNR);2)still has good performance under small snapshots;3)is robuster and easier to be realized when comparing with minimum variance distortionless response(MVDR)and the traditional diagonal loading algorithms. 展开更多
关键词 angle reciprocity covariance matrix reconstruction interference suppression satellite communications worst-case performance optimization
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Double tract reconstruction in proximal gastric tumors:A systematic review of clinical and functional outcomes
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作者 Enver Ilhan Gökalp Okut 《World Journal of Gastrointestinal Surgery》 2025年第9期355-366,共12页
BACKGROUND Proximal gastrectomy(PG)with double tract reconstruction(DTR)has recently emerged as a function-preserving alternative to total gastrectomy(TG)with Rouxen-Y(RNY)reconstruction in patients with proximally lo... BACKGROUND Proximal gastrectomy(PG)with double tract reconstruction(DTR)has recently emerged as a function-preserving alternative to total gastrectomy(TG)with Rouxen-Y(RNY)reconstruction in patients with proximally located gastric cancer.AIM To evaluate the current evidence comparing PG-DTR with TG-RNY in terms of perioperative outcomes,long-term survival,complication rates,nutritional status and reflux esophagitis.METHODS A systematic literature search was conducted using PubMed,MEDLINE,Web of Science and the Cochrane Library for studies published between 2010 and January 2025.Search terms included gastric cancer,DTR and TG.Trials comparing PGDTR with TG-RNY or PG-esophagogastrostomy(EG)were included.Data on operative details,lymph node yield,complications(Clavien-Dindo≥III),nutritional markers and incidence of reflux were extracted.Nineteen trials met the inclusion criteria.The review followed the PRISMA guidelines.RESULTS PG-DTR was found to have comparable long-term oncological outcomes to TGRNY,despite a lower extent of lymph node dissection.Operative time and intraoperative blood loss were generally similar,with some studies favouring PGDTR.Rates of major postoperative complications were comparable between techniques.Notably,PG-DTR showed a significantly lower incidence of reflux esophagitis than PG-EG and was comparable or superior to TG-RNY in reflux control.Nutritionally,PG-DTR was associated with better post-operative weight maintenance and biochemical parameters such as haemoglobin,albumin and vitamin B12 levels compared to TG-RNY.No significant nutritional differences were observed between PG-DTR and PG-EG.PG-DTR appears to offer a balanced approach to the surgical treatment of proximal gastric cancer,combining oncological safety with functional and nutritional benefits.CONCLUSION Its superiority over TG-RNY in postoperative nutrition and reflux prevention,together with comparable complication rates and survival,supports its consideration as a preferred reconstruction method in selected patients. 展开更多
关键词 Nutritional outcomes Reflux esophagitis Gastric cancer Total gastrectomy Double tract reconstruction Proximal gastrectomy
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S Zorb装置中吸附剂流化状态对脱硫性能的影响
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作者 王文寿 王煦烨 +2 位作者 张文吉 刘玉良 朱丙田 《石油炼制与化工》 北大核心 2026年第1期36-43,共8页
针对工业S Zorb汽油脱硫装置出现吸附剂脱硫性能下降、反应器横管及卸剂线卸出的吸附剂粒径及性质出现明显差异的情况,在小型固定床反应器上,考察了S Zorb装置吸附剂粒径对其脱硫活性的影响,结果表明:吸附剂粒径大小对催化裂化汽油脱硫... 针对工业S Zorb汽油脱硫装置出现吸附剂脱硫性能下降、反应器横管及卸剂线卸出的吸附剂粒径及性质出现明显差异的情况,在小型固定床反应器上,考察了S Zorb装置吸附剂粒径对其脱硫活性的影响,结果表明:吸附剂粒径大小对催化裂化汽油脱硫活性影响不大。利用计算流体力学(CFD)仿真手段模拟了吸附剂粒径、反应器藏量、吸附剂密度及进料分布器堵塞等对吸附剂流化状态的影响,结果表明:在吸附剂总质量相同的情况下,吸附剂粒径变大,使得反应器的密相床层高度降低,稀相空间内以颗粒半径小于40μm的吸附剂为主;吸附剂藏量减少或者吸附剂堆密度增加,导致吸附剂密相床层料位降低;当密相床层料位低于反应器中上部的转剂横管时,密相床层内的大颗粒吸附剂不能正常参与反应-再生循环,参与反应-再生循环的吸附剂以稀相床层中的小颗粒吸附剂为主,脱硫反应器整体脱硫效率降低。通过调整反应参数提高反应器密相床层料位较好地解决了装置脱硫效率低的问题。 展开更多
关键词 s ZORB 吸附脱硫 粒径 密相床层 稀相床层
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Sphincter-preserving surgical techniques in low rectal cancer management:A systematic review of contemporary evidence
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作者 Song Wang A-Jian Li +2 位作者 Hui-Hong Jiang Yin Lin Hai-Bo Ding 《World Journal of Gastrointestinal Surgery》 2025年第7期41-52,共12页
Rectal cancer ranks as the third most prevalent malignancy globally,with an estimated 1.9 million incident cases reported in 2020.The management of low rectal cancer presents significant therapeutic challenges due to ... Rectal cancer ranks as the third most prevalent malignancy globally,with an estimated 1.9 million incident cases reported in 2020.The management of low rectal cancer presents significant therapeutic challenges due to its anatomical complexity,and substantially impacts patients'quality of life.While abdominoperineal resection(Miles procedure)ensures oncological radicality,the morbidity associated with permanent colostomy has driven innovations in sphincter-preserving surgical techniques.This review synthesizes current evidence on sphincter-preserving surgical approaches for low rectal cancer.The implementation of total mesorectal excision(TME)principles and enhanced understanding of circumferential resection margin have facilitated the evolution of diverse sphincter-preserving surgical modalities.These include local excision,low anterior resection(Dixon procedure),intersphincteric resection,pull-through procedures,transanal TME,and conventional sphincter-preserving operation.Minimally invasive approaches,particularly laparoscopic and robotic platforms,alongside natural orifice transluminal endoscopic surgery,have demonstrated improved surgical precision and enhanced postoperative recovery outcomes.Novel functional perineal reconstruction techniques offer promising alternatives for patients requiring posterior pelvic exenteration.Nevertheless,the high incidence of low anterior resection syndrome(LARS)and its chronic sequelae remain clinically notable.Evidence indicates that long-course neoadjuvant radiotherapy and TME constitute significant risk factors for LARS development.Contemporary sphincter-preserving surgery for low rectal cancer is advancing toward minimally invasive,personalized,and precision-based approaches.The increasing incidence of early-onset rectal cancer necessitates individualized treatment strategies that balance oncological efficacy with functional preservation.Future directions should focus on standardizing surgical indications,optimizing postoperative rehabilitation protocols,and enhancing treatment outcomes through multidisciplinary integration and technological innovation. 展开更多
关键词 Low rectal cancer sphincter-preserving surgery Minimally invasive techniques Functional reconstruction Quality of life
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Oilfield sustainability and management:An optimization model for the reconstruction of oil and gas gathering systems based on potential location mining
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作者 Jie Chen Wei Wang +2 位作者 Wen-Yuan Sun Dong Li Yu-Bo Jiao 《Petroleum Science》 2025年第2期935-955,共21页
The carbon emissions and cost during the construction phase are significant contributors to the oilfield lifecycle.As oilfields enter the late stage,the adaptability of facilities decreases.To achieve sustainable deve... The carbon emissions and cost during the construction phase are significant contributors to the oilfield lifecycle.As oilfields enter the late stage,the adaptability of facilities decreases.To achieve sustainable development,oilfield reconstruction was usually conducted in discrete rather than continuous space.Motivated by economic and sustainability goals,a 3-phase heuristic model for oilfield reconstruction was developed to mine potential locations in continuous space.In phase 1,considering the process characteristics of the oil and gas gathering system,potential locations were mined in continuous space.In phase 2,incorporating comprehensive reconstruction measures,a reconstruction model was established in discrete space.In phase 3,the topology was further adjusted in continuous space.Subsequently,the model was transformed into a single-objective mixed integer linear programming model using the augmented ε-constraint method.Numerical experiments revealed that the small number of potential locations could effectively reduce the reconstruction cost,and the quality of potential locations mined in phase 1 surpassed those generated in random or grid form.Case studies showed that cost and carbon emissions for a new block were reduced by up to 10.45% and 7.21 %,respectively.These reductions were because the potential locations mined in 1P reduced the number of metering stations,and 3P adjusted the locations of metering stations in continuous space to shorten the pipeline length.For an old oilfield,the load and connection ratios of the old metering station increased to 89.7% and 94.9%,respectively,enhancing operation efficiency.Meanwhile,recycling facilitated the diversification of reconstruction measures and yielded a profit of 582,573 ¥,constituting 5.56% of the total cost.This study adopted comprehensive reconstruction measures and tapped into potential reductions in cost and carbon emissions for oilfield reconstruction,offering valuable insights for future oilfield design and construction. 展开更多
关键词 Oilfield reconstruction sustainable development Optimization model Potential location3-phase heuristic model
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PLayer: a plug-and-play embedded neural system to boost neural organoid 3D reconstruction
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作者 Yuanzheng Ma Davit Khutsishvili +7 位作者 Zihan Zang Wei Yue Zhen Guo Tao Feng Zitian Wang Liwei Lin Shaohua Ma Xun Guan 《Advanced Photonics Nexus》 2025年第3期79-91,共13页
Neural organoids and confocal microscopy have the potential to play an important role in microconnectome research to understand neural patterns.We present PLayer,a plug-and-play embedded neural system,which demonstrat... Neural organoids and confocal microscopy have the potential to play an important role in microconnectome research to understand neural patterns.We present PLayer,a plug-and-play embedded neural system,which demonstrates the utilization of sparse confocal microscopy layers to interpolate continuous axial resolution.With an embedded system focused on neural network pruning,image scaling,and post-processing,PLayer achieves high-performance metrics with an average structural similarity index of 0.9217 and a peak signal-to-noise ratio of 27.75 dB,all within 20 s.This represents a significant time saving of 85.71%with simplified image processing.By harnessing statistical map estimation in interpolation and incorporating the Vision Transformer–based Restorer,PLayer ensures 2D layer consistency while mitigating heavy computational dependence.As such,PLayer can reconstruct 3D neural organoid confocal data continuously under limited computational power for the wide acceptance of fundamental connectomics and pattern-related research with embedded devices. 展开更多
关键词 neural connectivity 3D reconstruction deep learning ORGANOIDs confocal microscopy embedded neural network
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