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Perrault综合征相关耳聋基因HARS2研究进展
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作者 於镇寰 李志祥 庞秀红 《中华耳科学杂志》 北大核心 2025年第9期1068-1072,共5页
Perrault综合征是一种罕见的常染色体隐性遗传病,以感音神经性听力损失和女性卵巢功能障碍为主要临床特征。目前已有研究表明,HARS2、CLPP、ERAL1、GGPS1、HSD17B4、LARS2、RMND1及TWNK等8种基因的突变与该综合征相关。本文系统综述了HA... Perrault综合征是一种罕见的常染色体隐性遗传病,以感音神经性听力损失和女性卵巢功能障碍为主要临床特征。目前已有研究表明,HARS2、CLPP、ERAL1、GGPS1、HSD17B4、LARS2、RMND1及TWNK等8种基因的突变与该综合征相关。本文系统综述了HARS2基因的结构、突变类型及其致病机制,重点探讨了突变对蛋白质稳定性、氨酰化活性及线粒体功能的影响,以期为该综合征的早期诊断与靶向治疗提供理论依据。 展开更多
关键词 hars2 Perrault综合征 感音神经性听力损失 线粒体功能障碍
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HARS2基因突变致以耳聋为表现的Perrault综合征机制的研究 被引量:3
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作者 梁云红 陈曦 +5 位作者 费静 余莉亚 廖娜 庄璐 杨婷钰 李雷激 《中国耳鼻咽喉颅底外科杂志》 CAS 2022年第6期19-26,共8页
目的研究耳聋家系HARS2基因突变位点对HARS2蛋白的影响,为研究HARS2基因突变致Perrault综合征的发病机制奠定基础。方法检测并验证该家系成员样本DNA的HARS2基因。使用软件对蛋白质建模,分析预测Asp117Asn和Leu303Pro突变对HARS2蛋白结... 目的研究耳聋家系HARS2基因突变位点对HARS2蛋白的影响,为研究HARS2基因突变致Perrault综合征的发病机制奠定基础。方法检测并验证该家系成员样本DNA的HARS2基因。使用软件对蛋白质建模,分析预测Asp117Asn和Leu303Pro突变对HARS2蛋白结构稳定性的影响。转染含野生型HARS2基因和HARS2基因Asp117Asn突变、Leu303Pro突变的慢病毒重组质粒以及空载体至HEK 293T细胞(人胚肾细胞)中,分别获得WT细胞组(转染野生型的HEK293T细胞)、Asp117Asn细胞组(转染Asp117Asn突变的HEK293T细胞)、Leu303Pro细胞组(转染Leu303Pro突变的HEK293T细胞)、NC细胞组(转染空病毒载体的HEK293T细胞)。Northern blot检测线粒体tRNAHis氨酰化水平;Western blot检测HARS2蛋白的表达;免疫荧光测定HARS2蛋白表达部位。结果①先证者及其哥哥为耳聋患者,为HARS2 c.349G>A(p.Asp117Asn)和c.908T>C(p.Leu303Pro)复合杂合突变;其父亲为HARS2 c.908T>C(p.Leu303Pro)杂合突变;其外婆、母亲、舅舅为HARS2349G>A(p.Asp117Asn)杂合突变;②突变可能导致HARS2蛋白稳定性下降;③WT细胞组线粒体tRNAHis氨酰化水平高于其余3组(P<0.05);Asp117Asn细胞组较Leu303Pro细胞组线粒体tRNAHis氨酰化水平高(P=0.016);④HARS2蛋白均于线粒体表达;⑤HARS2蛋白在NC细胞组中无明显表达;WT细胞组HARS2蛋白表达与Asp117Asn细胞组无明显差异(P=0.356),高于Leu303Pro细胞组(P=0.000)。结论①明确了HARS2基因2个新突变位点c.349G>A和c.908T>C;②该突变可能通过降低HARS2蛋白氨酰化能力和/或表达,导致线粒体tRNAHis氨酰化能力降低,进而出现线粒体功能障碍,从而导致听力损失。 展开更多
关键词 耳聋 hars2 基因突变 Perrault综合征 氨酰化水平
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Perrault综合征HARS2基因c.349G>A和c.908T>C突变对细胞线粒体功能的影响 被引量:1
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作者 宋坭洁 费静 +3 位作者 廖娜 庄璐 杨婷钰 李雷激 《中国耳鼻咽喉颅底外科杂志》 CAS CSCD 2023年第4期14-19,共6页
目的探讨HARS2基因c.349G>A和c.908T>C两个位点的突变对细胞和线粒体功能的影响,以期揭示HARS2新突变位点的致病机制。方法构建含野生型、c.349G>A突变型、c.908T>C突变型HARS2基因的重组表达载体,使用慢病毒包装系统将质... 目的探讨HARS2基因c.349G>A和c.908T>C两个位点的突变对细胞和线粒体功能的影响,以期揭示HARS2新突变位点的致病机制。方法构建含野生型、c.349G>A突变型、c.908T>C突变型HARS2基因的重组表达载体,使用慢病毒包装系统将质粒转染至HEK 293T细胞中,通过嘌呤霉素筛选获得稳定转染野生型、突变型HARS2基因的细胞系,同时建立稳定转染空病毒载体的细胞系作为对照,对野生组、c.349G>A突变组、c.908T>C突变组和对照组细胞的线粒体功能和细胞增殖能力进行研究。结果重组质粒在预期位点发生了突变,重组载体携带的绿色荧光蛋白(EGFP)稳定表达;两突变组细胞增殖活力较野生组下降,72 h吸光度有显著性差异(P<0.05);c.349G>A突变组MTCO 2蛋白表达量较对照组和野生组均有下降(P<0.05);c.349G>A突变组和c.908T>C突变组的线粒体ATP相对细胞总ATP产率较对照组均有降低(P<0.05);c.349G>A突变组线粒体活性氧自由基(ROS)水平较对照组明显增加(P<0.05);两突变组线粒体膜电位(MMP)较野生组下降(P<0.01)。结论HARS2基因c.349G>A、c.908T>C突变细胞的线粒体存在一定的呼吸功能缺陷,突变细胞增殖能力下降,可能是HARS2基因突变致Perrault综合征的细胞学机制。 展开更多
关键词 Perrault综合征 hars2 基因突变 线粒体
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LARS2和 HARS2基因致病变异所致的Perrault综合征分析 被引量:1
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作者 雷一波 孙淑萍 +4 位作者 毛璐 许红恩 汤文学 潘昭宇 卢伟 《中华耳鼻咽喉头颈外科杂志》 CSCD 北大核心 2023年第12期1191-1197,共7页
目的分析并揭示Perrault综合征患者的分子病因。方法选取郑州大学第一附属医院2021年2月至2022年3月收治的2例以双耳重度感音神经性听力损失为特征的男性Perrault综合征患者,总结患者及其家系的临床表型及基因变异,应用全外显子测序(who... 目的分析并揭示Perrault综合征患者的分子病因。方法选取郑州大学第一附属医院2021年2月至2022年3月收治的2例以双耳重度感音神经性听力损失为特征的男性Perrault综合征患者,总结患者及其家系的临床表型及基因变异,应用全外显子测序(whole exome sequencing,WES)技术对先证者进行致病变异筛选,结合临床表型确定候选基因及致病位点,用Sanger测序法对先证者及其家系成员进行验证。结果WES结果显示家系1的先证者存在LARS2基因(NM_015340.4)c.1565C>A(p.Thr522Asn)和c.1079T>C(p.Ile360Thr)的复合杂合变异,c.1565C>A来自先证者母亲,c.1079T>C来自先证者父亲。其中,c.1565C>A为已报道的致病变异,c.1079T>C为新变异。家系2先证者携带HARS2基因(NM_012208.4)c.1273C>T(p.Arg425Trp)和c.1403G>C(p.Gly468Ala)的复合杂合变异,c.1273C>T来自母亲,c.1403G>C来自父亲,c.1273C>T为新变异,c.1403G>C为已报道可能致病变异。参考美国医学遗传学与基因组学学会基因变异分类标准,上述变异分别评级为致病、意义未明、意义未明和可能致病。结论本研究扩大了LARS2和HARS2基因的突变谱,基因检测在综合征型耳聋的早期诊断中发挥着重要作用。 展开更多
关键词 听觉丧失 感音神经性 LARS2 hars2 Perrault综合征
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基于长期记忆性动态因子的已实现协方差矩阵预测模型
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作者 刘广应 翁求磊 庄子言 《统计与决策》 北大核心 2026年第6期154-159,共6页
高维协方差矩阵的预测建模,对于投资组合和金融风险管理至关重要。文章基于2005—2025年的金融高频数据,得到已实现协方差矩阵,对其进行Cholesky分解,将分解所得下三角矩阵拉直向量化,进而构建动态因子模型(DFM),并对因子向量采用异质... 高维协方差矩阵的预测建模,对于投资组合和金融风险管理至关重要。文章基于2005—2025年的金融高频数据,得到已实现协方差矩阵,对其进行Cholesky分解,将分解所得下三角矩阵拉直向量化,进而构建动态因子模型(DFM),并对因子向量采用异质自回归(HAR)模型,构建长期记忆性动态因子(CDFM-HAR)已实现协方差矩阵预测模型,进一步对模型进行参数估计和预测。对CDFM-HAR已实现协方差矩阵预测模型进行随机模拟和实证研究后发现,估计方法具有良好的准确性,与其他的已实现协方差预测模型相比,CD⁃FM-HAR模型预测更为准确,投资组合表现更优。 展开更多
关键词 高频数据 已实现协方差矩阵 动态因子模型 HAR 投资组合
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MFCCT:A Robust Spectral-Temporal Fusion Method with DeepConvLSTM for Human Activity Recognition
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作者 Rashid Jahangir Nazik Alturki +1 位作者 Muhammad Asif Nauman Faiqa Hanif 《Computers, Materials & Continua》 2026年第2期852-871,共20页
Human activity recognition(HAR)is a method to predict human activities from sensor signals using machine learning(ML)techniques.HAR systems have several applications in various domains,including medicine,surveillance,... Human activity recognition(HAR)is a method to predict human activities from sensor signals using machine learning(ML)techniques.HAR systems have several applications in various domains,including medicine,surveillance,behavioral monitoring,and posture analysis.Extraction of suitable information from sensor data is an important part of the HAR process to recognize activities accurately.Several research studies on HAR have utilizedMel frequency cepstral coefficients(MFCCs)because of their effectiveness in capturing the periodic pattern of sensor signals.However,existing MFCC-based approaches often fail to capture sufficient temporal variability,which limits their ability to distinguish between complex or imbalanced activity classes robustly.To address this gap,this study proposes a feature fusion strategy that merges time-based and MFCC features(MFCCT)to enhance activity representation.The merged features were fed to a convolutional neural network(CNN)integrated with long shortterm memory(LSTM)—DeepConvLSTM to construct the HAR model.The MFCCT features with DeepConvLSTM achieved better performance as compared to MFCCs and time-based features on PAMAP2,UCI-HAR,and WISDM by obtaining an accuracy of 97%,98%,and 97%,respectively.In addition,DeepConvLSTM outperformed the deep learning(DL)algorithms that have recently been employed in HAR.These results confirm that the proposed hybrid features are not only practical but also generalizable,making them applicable across diverse HAR datasets for accurate activity classification. 展开更多
关键词 DeepConvLSTM human activity recognition(HAR) MFCCT feature fusion wearable sensors
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A Hybrid Deep Learning Approach for IoT-Enabled Human Activity Recognition and Advanced Analytics
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作者 Shtwai Alsubai Abdullah Al Hejaili +2 位作者 Najib Ben Aoun Amina Salhi Vincent Karovic 《Computers, Materials & Continua》 2026年第5期1546-1563,共18页
The concept of Human Activity Recognition(HAR)is integral to applications based on Internet of Things(IoT)-enabled devices,particularly in healthcare,fitness tracking,and smart environments.The streams of data from we... The concept of Human Activity Recognition(HAR)is integral to applications based on Internet of Things(IoT)-enabled devices,particularly in healthcare,fitness tracking,and smart environments.The streams of data from wearable sensors are rich in information,yet their high dimensionality and variability pose a significant challenge to proper classification.To address this problem,this paper proposes hybrid architectures that integrate traditional machine learning models with a deep neural network(DNN)to deliver improved performance and enhanced capabilities for HAR tasks.Multi-sensor HAR data were used to systematically test several hybrid models,including:RF+DNN(Random Forest+Deep Neural Network),XGB+DNN(XGBoost+DNN),GB+DNN(Gradient Boosting+DNN),KNN+DNN(K-Nearest Neighbors+DNN),and DT+DNN(Decision Tree+DNN).The RF+DNN model was the most accurate,achieving a 97.03%score with excellent precision,recall,and F1-score.These findings demonstrate that hybrid machine learning and deep learning systems have a promising future in IoT-based HAR applications.The model provides a novel solution for developing smart and trustworthy monitoring systems that support real-time analytics,patient surveillance,and other IoT applications. 展开更多
关键词 Human activity recognition(HAR) Internet of Things(IoT) wearable sensors hybrid models deep neural networks(DNN)
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基于日内收益水平的已实现波动率分解及波动率预测
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作者 瞿慧 上官鹏 《运筹与管理》 北大核心 2025年第11期122-128,共7页
考虑到不同水平的日内收益可能蕴含不同的市场未来波动有益信息,基于日内收益水平将已实现波动分解为高、中、低收益变差,并参考PATTON和SHEPPARD(2015)的HAR-RV-RS模型构建区分高、中、低收益变差贡献的HAR-RV-R模型。采用中国股票指... 考虑到不同水平的日内收益可能蕴含不同的市场未来波动有益信息,基于日内收益水平将已实现波动分解为高、中、低收益变差,并参考PATTON和SHEPPARD(2015)的HAR-RV-RS模型构建区分高、中、低收益变差贡献的HAR-RV-R模型。采用中国股票指数五分钟数据的实证表明,HAR-RV-R模型相比HAR-RV-RS模型在拟合与预测上都有明显改进,证明基于日内收益水平的已实现波动分解更为有效。进一步地,分别考察高、中、低收益变差对指数未来波动的解释能力,实证表明:(1)相对于高、低收益变差,中收益变差具有突出的解释能力;(2)高、中、低收益变差的日、周、月变量解释能力有明显分化,且月变量解释能力最强。最后,考虑到中收益变差本质上也是对波动中跳跃成分的一种剥离,对比其与多种跳跃识别方法下构建的连续波动估计量对未来波动的解释能力,实证指出引入中收益变差的模型具有更强的样本外预测精度,再次说明基于日内收益水平的已实现波动分解虽简单但有效。本文提出的已实现波动分解方法及实证结论对于风险管理与衍生产品定价等金融实务都具有重要价值。 展开更多
关键词 波动率预测 已实现波动率 HAR模型 日内收益水平 波动率分解 跳跃
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基于“家电以旧换新”回收数据评估电子废物产生量估算方法 被引量:18
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作者 童昕 蔡一帆 颜琳 《生态经济》 CSSCI 北大核心 2013年第7期38-42,共5页
比较了基于史坦福(Stanford)模型和保有量系数法对我国电子废物产生量的预测,并与中国家电以旧换新活动试点区域的实际回收统计数据进行对比,结果显示除电视机以外,两种估计方法的预测结果都显著高于以旧换新的实际回收数据。其原因首... 比较了基于史坦福(Stanford)模型和保有量系数法对我国电子废物产生量的预测,并与中国家电以旧换新活动试点区域的实际回收统计数据进行对比,结果显示除电视机以外,两种估计方法的预测结果都显著高于以旧换新的实际回收数据。其原因首先是产品废弃量的变化深受产品技术变化影响,平板显示技术的快速普及导致CRT电视机废弃量出现短期激增,成为"家电以旧换新"实际回收品的主体,而洗衣机、电冰箱等传统大家电的产品实际使用寿命相对较长;其次是废旧产品回收面临非正式回收部门的竞争,以旧换新以较高的政府补贴引导一定数量的废弃产品流向正规处理企业,但还有相当数量的废旧产品流入了非正式的翻新加工和二手销售渠道。特别是空调和电脑,家庭消费占总消费量的比重较小,产品废弃后的材料回收价值和翻新维修价值都较高,补贴对提升回收量的影响相对较小;最后不同区域之间,预测结果与实际回收情况对比也存在明显的差别。考虑到家电以旧换新政策停止以后,新颁布实施的废弃电器电子产品回收处理基金的补助力度大幅下降,有资质的回收处理企业重新陷入发展困境。有必要遵循生产者责任延伸制度的原则,积极鼓励扩大生产者的参与,从产品设计和废弃产品回收的逆向物流两方面提高回收利用系统的效率。同时,合理规划再生处理设施的区位和处理规模,需要根据区域和产品特点,对现有预测方法进行优化调整。 展开更多
关键词 生产者责任延伸制度(EPR) 家电以旧换新项目(hars) 废弃电子电器产品(WEEE) 废弃量预测模型
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Crustal velocity structure and composition of Bayan Har block and surrounding areas
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作者 Jiyan Lin Tao Xu +3 位作者 Zhenyu Fan Yong Qiu Minjie Chen Yonghong Duan 《Earthquake Research Advances》 2025年第3期47-55,共9页
The Bayan Har block,one of China's most seismically active regions,has experienced multiple major earthquakes(≥M 7.0)in recent years.It is a key area for investigating the interactions between the Qinghai-Xizang(... The Bayan Har block,one of China's most seismically active regions,has experienced multiple major earthquakes(≥M 7.0)in recent years.It is a key area for investigating the interactions between the Qinghai-Xizang(Qingzang)Plateau and adjacent blocks,plateau uplift,and strong earthquake mechanisms.P-wave velocity and crustal composition provide key constraints on the properties of distinct tectonic units and their evolutionary modification processes.Based on the results of 8 Deep Seismic Sounding(DSS)profiles completed in the Bayan Har block and surrounding areas over the past 20 years,We constructed one-dimensional P-wave velocity models for the crust of Bayan Har block,Qilian fold belt,Qinling fold belt,Alxa block,Ordos block and Sichuan basin.Furthermore,crustal composition models for different tectonic units were established based on these results.The results reveal that the crustal thickness of the Bayan Har block gradually decreases towards the NNE,NE,and SE directions,while the average crustal velocity increases correspondingly.The felsic layer in the crust accounts for more than half of the total crustal thickness.The mafic content within the crust of different tectonic units exhibits notable variations,which may reflect that the Bayan Har block,Qilian fold belt,and Qinling fold belt have experienced more intensive lithospheric evolution processes compared to Ordos basin and Sichuan basin.The seismicity distribution in this region is significantly controlled by crustal velocity and composition heterogeneity across the Bayan Har block and adjacent areas,which demonstrates that earthquakes within and around the Bayan Har block exhibit both high frequency and larger magnitudes.These seismic characteristics primarily result from intense crustal stress accumulation and release during the outward expansion of the Qingzang Plateau. 展开更多
关键词 NE Qingzang plateau Bayan Har Crustal velocity structure Crustal composition
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ISO Annual Meeting
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《China Standardization》 2025年第4期59-59,共1页
The ISO Annual Meeting is the world’s premier event for the international standards community.This year’s event is hosted by RSB,the national standards body of Rwanda.The theme“United for impact”calls us to harnes... The ISO Annual Meeting is the world’s premier event for the international standards community.This year’s event is hosted by RSB,the national standards body of Rwanda.The theme“United for impact”calls us to harness our collective strength in a world that needs bold,lasting change.The ISO Annual Meeting convenes global leaders and change-makers to explore how international standards can unlock progress,foster trust and drive lasting solutions to our shared challenges. 展开更多
关键词 bold change harness our collective strength international standards global leaders collective strength standards body change makers ISO annual meeting
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Eco-Friendly Particleboards Produced with Banana Tree(Musa paradisiaca)Pseudostem Fibers Bonded with Cassava Starch and Urea-Formaldehyde Adhesives
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作者 Prosper Mensah Rafael Rodolfode Melo +3 位作者 Edgley Alves de Oliveira Paula Alexandre Santos Pimenta Julianade Moura Fernando Rusch 《Journal of Renewable Materials》 2025年第7期1475-1489,共15页
The increase in wood and wood-based products in the construction and furniture sectors has grown exponentially,generating severe environmental and socioeconomic impacts.Particleboard panels have been the main cost-ben... The increase in wood and wood-based products in the construction and furniture sectors has grown exponentially,generating severe environmental and socioeconomic impacts.Particleboard panels have been the main cost-benefit option on the market due to their lightness and lower cost compared to solid wood.However,the synthetic adhesives used in producing traditional particleboard panels cause serious harm to human health.Developing particleboard panels with fibrous waste and natural adhesives could be a sustainable alternative for these sectors.The work aimed to create particleboards with fibrous wastes from the pseudostem of the banana tree(Musa paradisiaca)and different proportions of the natural adhesive cassava starch-CS in replacement of synthetic adhesive urea-formaldehyde-UF.Five experimental groups were manufactured with banana trees and different percentages of UF and CS adhesives,namely(100UF–0%CS),(50%UF–50%CS),(30%UF–70%CS),(10%UF–90%CS)and(0%UF–100%CS).The particleboards had their physical-mechanical properties determined.The apparent density values did not show significant variation between the assessed treatments.Regarding the water absorption and thickness swelling,the best performances were observed for the panels made without the addition of CS(100%UF).For the mechanical properties of static bending strength and Janka hardness,it was identified that adding up to 50%CS did not interfere with the quality of the panels.These analyses show that the particleboard panels produced with wastes of the banana tree bonded with natural CS adhesivemay be an economically viable and environmentally correct alternative,positively strengthening the development of sustainable strategies. 展开更多
关键词 Plant fibers vegetable waste harnessing bioadhesives physical and technological properties sustainable development
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行为金融因子能否提高波动率预测精度?——基于沪铜期货市场的证据
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作者 陈振彪 《中国证券期货》 2025年第3期27-36,共10页
有效市场假说认为金融资产的价格反映一系列有价值的信息,而信息同样对价格波动产生重要影响,对此,引入行为金融因子——投资者关注度和宏观冲击变量对异质自回归HAR族模型进行改进,选用上海期货交易所铜期货5分钟高频数据作为研究样本... 有效市场假说认为金融资产的价格反映一系列有价值的信息,而信息同样对价格波动产生重要影响,对此,引入行为金融因子——投资者关注度和宏观冲击变量对异质自回归HAR族模型进行改进,选用上海期货交易所铜期货5分钟高频数据作为研究样本,分短中长三个时期的已实现波动率做样本内参数估计、样本外预测的数据精度分析及投资决策当中的经济价值分析,最后进行稳健性检验。结果表明,投资者关注度和宏观冲击变量的引入能够提高HAR族模型构造的拟合效度,并且考虑投资者关注度改进的HAR-ES-BI模型和HAR-ES-GI模型较于基准模型有着明显的预测精度和经济价值提升,特别是预测短期波动率;相较于国外投资者,本国投资者关注度发挥更为显著的作用。 展开更多
关键词 HAR模型 投资者关注度 铜期货市场 行为金融 MCS检验 经济价值分析
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Deep Learning and Federated Learning in Human Activity Recognition with Sensor Data:A Comprehensive Review
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作者 Farhad Mortezapour Shiri Thinagaran Perumal +1 位作者 Norwati Mustapha Raihani Mohamed 《Computer Modeling in Engineering & Sciences》 2025年第11期1389-1485,共97页
Human Activity Recognition(HAR)represents a rapidly advancing research domain,propelled by continuous developments in sensor technologies and the Internet of Things(IoT).Deep learning has become the dominant paradigm ... Human Activity Recognition(HAR)represents a rapidly advancing research domain,propelled by continuous developments in sensor technologies and the Internet of Things(IoT).Deep learning has become the dominant paradigm in sensor-based HAR systems,offering significant advantages over traditional machine learning methods by eliminating manual feature extraction,enhancing recognition accuracy for complex activities,and enabling the exploitation of unlabeled data through generative models.This paper provides a comprehensive review of recent advancements and emerging trends in deep learning models developed for sensor-based human activity recognition(HAR)systems.We begin with an overview of fundamental HAR concepts in sensor-driven contexts,followed by a systematic categorization and summary of existing research.Our survey encompasses a wide range of deep learning approaches,including Multi-Layer Perceptrons(MLP),Convolutional Neural Networks(CNN),Recurrent Neural Networks(RNN),Long Short-Term Memory networks(LSTM),Gated Recurrent Units(GRU),Transformers,Deep Belief Networks(DBN),and hybrid architectures.A comparative evaluation of these models is provided,highlighting their performance,architectural complexity,and contributions to the field.Beyond Centralized deep learning models,we examine the role of Federated Learning(FL)in HAR,highlighting current applications and research directions.Finally,we discuss the growing importance of Explainable Artificial Intelligence(XAI)in sensor-based HAR,reviewing recent studies that integrate interpretability methods to enhance transparency and trustworthiness in deep learning-based HAR systems. 展开更多
关键词 Human activity recognition(HAR) machine learning deep learning SENSORS Internet of Things federated learning(FL) explainable AI(XAI)
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Loss of CsPOD7 triggers ROS-induced metabolic collapse and male sterility in cucumber
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作者 Sen Li Yuming Dong +11 位作者 Xi Zhao Li Shan Lin Yang Menghang An Tiantian Pei Muhammad Ahmad Yifan Xu Yibing Zhao Hao Xue Xinyue Ma Xingwang Liu Huazhong Ren 《Horticultural Plant Journal》 2025年第6期2292-2296,共5页
Male sterile lines serve as a pivotal tool in plant breeding,offering an effective strategy for developing hybrid cultivars.In cucumber(Cucumis sativus L.),the creation of male sterile lines,most of which exhibit abno... Male sterile lines serve as a pivotal tool in plant breeding,offering an effective strategy for developing hybrid cultivars.In cucumber(Cucumis sativus L.),the creation of male sterile lines,most of which exhibit abnormal pollen development,is essential for harnessing heterosis.Accumulating evidence suggests that male sterility in plants is linked to the overaccumulation of Reactive Oxygen Species(ROS),which causes oxidative damage to biomolecules and cellular structures,ultimately leading to aberrant anther development(Li et al.,2004). 展开更多
关键词 creation male sterile linesmost abnormal pollen developmentis male sterility reactive oxygen species ros which cspod harnessing heterosisaccumulating male sterile lines developing hybrid cultivarsin
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Good things come in pairs:Crop disease resistance from sensor–helper to sensor–executor pairs
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作者 Brande B.H.Wulff Zhiyong Liu 《The Crop Journal》 2025年第6期1655-1659,共5页
1.Background Crop diseases diminish potential yields by over 20%annually worldwide[1],driving a century-long quest to understand and harness genetic resistance in plants.The genetic basis of disease resistance was fir... 1.Background Crop diseases diminish potential yields by over 20%annually worldwide[1],driving a century-long quest to understand and harness genetic resistance in plants.The genetic basis of disease resistance was first recognized in the early 1900s,when Biffen(1905)demonstrated that resistance to stripe rust in wheat(Triticum aestivum)followed Mendelian rules of inheritance[2].This foundational insight was later expanded by Flor(1942),who formulated the“gene-for-gene”model describing the genetic interplay between host resistance(R)genes and pathogen avirulence(Avr)genes[3]. 展开更多
关键词 sensor executor pairs stripe rust understand harness genetic resistance sensor helper pairs crop diseases mendelian rules inheritance genetic basis disease resistance genetic interplay
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应用全外显子组测序发现儿童罕见综合征耳聋 被引量:3
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作者 曲春燕 周怡 +3 位作者 陈敏 郝津生 倪鑫 刘海红 《罕见病研究》 2022年第3期278-282,共5页
目的探讨全外显子组测序方法对诊断儿童罕见综合征耳聋的意义。方法采用全外显子组测序技术对34例诊断为感音神经性听力损失患儿小家系进行分子病因学的检测和分析。结果19例患儿明确了分子病因,包括罕见的综合征耳聋4例,致病基因分别是... 目的探讨全外显子组测序方法对诊断儿童罕见综合征耳聋的意义。方法采用全外显子组测序技术对34例诊断为感音神经性听力损失患儿小家系进行分子病因学的检测和分析。结果19例患儿明确了分子病因,包括罕见的综合征耳聋4例,致病基因分别是HARS2、USH2A、GATA3和MITF;非综合征耳聋15例,包括GJB2基因突变8例,SLC26A4基因突变5例,MYO15A基因突变2例。HARS2基因的c.435_437del(p.K147del)和c.1403G>C(p.G468A)突变、USH2A基因的c.11389+1del突变、GATA3基因的c.1327delA(p.M443Wfs∗33)突变、MITF基因的c.627C>A(p.C209X)突变和MYO15A基因的c.8033_8057delinsG(p.N2678_D2686delinsS)突变均为首次报道。结论全外显子组测序技术有助于明确耳聋的致聋基因和突变,发现临床表型不明显的罕见综合征耳聋,并提示进一步完善相关系统或器官结构和功能的检查,对于临床诊断的准确性具有重要意义。 展开更多
关键词 全外显子组测序 综合征耳聋 hars2 USH2A GATA3 MITF MYO15A
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HAR族模型与GARCH族模型对不同期限波动率的预测精度比较——基于沪深300指数高频价格的实证分析 被引量:15
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作者 瞿慧 李洁 程昕 《系统工程》 CSSCI CSCD 北大核心 2015年第3期32-37,共6页
以对收益条件方差建模的GARCH族波动率模型,及对高频已实现波动建模的HAR族波动率模型为考察对象,采用滚动时间窗的样本外预测,结合具有Bootstrap特性的SPA检验法,分别使用4种常用的损失函数作为评价指标,比较了13种常用波动率模型对沪... 以对收益条件方差建模的GARCH族波动率模型,及对高频已实现波动建模的HAR族波动率模型为考察对象,采用滚动时间窗的样本外预测,结合具有Bootstrap特性的SPA检验法,分别使用4种常用的损失函数作为评价指标,比较了13种常用波动率模型对沪深300指数短期、中期、长期波动率的预测精度。实证结果表明,对数形式的HAR-RV-CJ模型对短期、中期、长期波动率的样本外预测都具有最高的精度,且对长期波动率预测的优势最为显著;对收益条件方差建模的GARCH族模型即便加入已实现波动作为附加解释变量,其预测精度仍无法超越对已实现波动直接建模的HAR族模型。 展开更多
关键词 波动率预测模型 HAR族模型 GARCH族模型 已实现波动 高频价格 SPA检验法
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中华眼镜蛇蛇毒及复方丹参抑制异种移植免疫排斥的实验研究 被引量:5
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作者 戚峰 王鹏志 +1 位作者 朱理玮 邱宇杰 《中草药》 CAS CSCD 北大核心 2001年第12期1106-1108,共3页
目的 研究中华眼睛蛇蛇毒因子 (CCV)及复方丹参在异种移植中的作用。方法 采用颈部套袖法建立豚鼠对大鼠心脏异种移植模型。于术前 2 4h按 0 .5 mg/ kg ip CCV,术中以复方丹参注射液灌注供心并 iv复方丹参。研究对照组、CCV组和 CCV+... 目的 研究中华眼睛蛇蛇毒因子 (CCV)及复方丹参在异种移植中的作用。方法 采用颈部套袖法建立豚鼠对大鼠心脏异种移植模型。于术前 2 4h按 0 .5 mg/ kg ip CCV,术中以复方丹参注射液灌注供心并 iv复方丹参。研究对照组、CCV组和 CCV+丹参组供心存活时间、复跳时间及血清补体水平的变化。结果  CCV可明显降低血清补体水平 ,延长供心存活时间 ,复方丹参注射液可缩短供心复跳时间。二者合用可进一步延长供心存活时间。结论 在异种移植中补体起着关键的作用 ,CCV通过降低血清补体水平抑制超急性排斥反应 (HAR)的发生 ,复方丹参可减少供心缺血损伤 ,并改善微循环 ,CCV和复方丹参合用对 HAR有良好的抑制效果。 展开更多
关键词 异种移植 中华眼镜蛇蛇毒 CCV 丹参 超急性排斥反应 HAR 补体 实验
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全球金融危机下的股票市场波动跳跃研究——基于高频数据的中美比较分析 被引量:12
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作者 西村友作 孙便霞 门明 《管理工程学报》 CSSCI 北大核心 2012年第1期106-112,共7页
本文以雷曼破产日至2009年1月底这段时期内上证综指、恒生指数以及S&P500指数的日内高频数据作为研究对象,采用跳跃显著性检验方法和扩展HAR模型,对波动跳跃特征进行了实证研究。结果表明:雷曼危机导致股市波动的显著提高,但中国内... 本文以雷曼破产日至2009年1月底这段时期内上证综指、恒生指数以及S&P500指数的日内高频数据作为研究对象,采用跳跃显著性检验方法和扩展HAR模型,对波动跳跃特征进行了实证研究。结果表明:雷曼危机导致股市波动的显著提高,但中国内地股市受到的影响最小;中国香港股市成为波动跳跃发生频率最高、跳跃幅度最大的市场,且波动跳跃主要发生在夜间休市时间内;雷曼危机使得波动率模型的预测精度大大降低,股市风险变得更加难以预测,对于新兴市场来说这一现象更加明显。 展开更多
关键词 雷曼危机 已实现波动率 跳跃扩散过程 跳跃显著性检验 HAR模型
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