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Advances in Atmospheric Sciences 2003年第3期20卷 475-478页

作者： robert e.dickinson Guiling WANG Xubin Zeng 曾庆存 Georgia Institute of Technology Atlanta GA Chinese Academy of Sciences Beijing 100080 University of Connecticut Storrs CT Chinese Academy of Sciences Beijing 100080 University of Arizona Tucson AZ Chinese Academy of Sciences Beijing 100080 Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100080

Water stored as part of the land surface is lost to evapotranspiration and runoff on different time scales, and the partitioning between these time scales is important for modeling soil water in a climate model. Different time scales are imposed on evapotranspiration primarily because it is derived from different reservoirs with different storage capacities, from the very rapid evaporation of canopy stores to the slow removal by transpiration of rooting zone soil moisture. Runoff likewise ranges in time scale from rapid surface terms to the slower base-flow. The longest time scale losses of water determine the slow variation of soil moisture and hence the longer time scale effects of soil moisture on precipitation. This paper shows with a simple analysis how shifting the partitioning of evapotranspiration between the different reservoirs affects the variability of soil moisture and precipitation. In particular, it is concluded that a shift to shorter time scale reservoirs shifts the variance of precipitation from that which is potentially predictable to unpredictable.

关键词： evapotranspiration climate model land surface coupling

evaluating Common Land Model energy Fluxes Using FLUXNeT Data

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Advances in Atmospheric Sciences 2017年第9期34卷 1035-1046页

作者： Xiangxiang ZHANG Yongjiu DAI Hongzhi CUI robert e.dickinson Siguang ZHU Nan WeI Binyan YAN Hua YUAN Wei SHANGGUAN Lili WANG Wenting FU College of Global Change and earth System Science Beijing Normal University School of Atmospheric Sciences Sun Yat-sen University Department of Geological Sciences the University of Texas at Austin

Given the crucial role of land surface processes in global and regional climates, there is a pressing need to test and verify the performance of land surface models via comparisons to observations. In this study, the eddy covariance measurements from 20 FLUXNeT sites spanning more than 100 site-years were utilized to evaluate the performance of the Common Land Model （CoLM） over different vegetation types in various climate zones. A decomposition method was employed to separate both the observed and simulated energy fluxes, i.e., the sensible heat flux, latent heat flux, net radiation, and ground heat flux, at three timescales ranging from stepwise （30 rain） to monthly. A comparison between the simulations and observations indicated that CoLM produced satisfactory simulations of all four energy fluxes, although the different indexes did not exhibit consistent results among the different fluxes, A strong agreement between the simulations and observations was found for the seasonal cycles at the 20 sites, whereas CoLM underestimated the latent heat flux at the sites with distinct dry and wet seasons, which might be associated with its weakness in simulating soil water during the dry season. CoLM cannot explicitly simulate the midday depression of leaf gas exchange, which may explain why CoLM also has a maximum diurnal bias at noon in the summer. Of the eight selected vegetation types analyzed, CoLM performs best for evergreen broadleaf forests and worst for croplands and wetlands.

关键词： model evaluation Common Land Model FLUXNeT

强对流过程对大尺度模式洋面通量加强的参数化研究与进展

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海洋学报 2001年第3期23卷 133-141页

作者：张强 ZeNG Xu-bin robert e.dickinson DANIeL e.Johnson TAO Wei-kuo 中国科学院寒区旱区环境与工程研究所甘肃兰州730000 Department of Atmospheric Sciences The University of ArizonaTucsonArizona Mesoscale Dynamicsand Precipitation Branch NASA/Gaddard Space Flight CenterGoddardGreenbelt

1引言由于地球表面热通量直接决定着大气环流运动,在大气数值模式中如何准确描述地球表面热通量就变处得十分重要.洋面是地球表面最广泛分布的下垫面,它的表面热通量描述尤为被重视.尤其是西赤道太平洋暖池、东赤道太平洋冷舌、ITCZ及... 详细信息

1引言由于地球表面热通量直接决定着大气环流运动,在大气数值模式中如何准确描述地球表面热通量就变处得十分重要.洋面是地球表面最广泛分布的下垫面,它的表面热通量描述尤为被重视.尤其是西赤道太平洋暖池、东赤道太平洋冷舌、ITCZ及信风带等关键区域的洋面热通量的准确估计更是非常重要,这些区域的地表通量变化通常被认为是全球气候变化即eNSO现象的最重要的信号[1].

关键词：中尺度对流系统洋面通量加强大尺度模式参数方案海气相互作用

大气和植被生态及土壤系统水文过程相互作用的一些研究

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大气科学 2005年第1期29卷 7-19页

作者：曾庆存曾晓东王爱慧 robert e.dickinson Xubin Zeng Samuel S.P.Shen 中国科学院大气物理研究所北京100029 中国科学院生物物理研究所北京100101The University of Arizona Tucson AZ USAUniversity of Alberta Edmonton AB Canada 中国科学院大气物理研究所北京100029The University of Arizona Tucson AZ USAUniversity of Alberta Edmonton AB Canada Georgia Institute of Technology Atlanta GA USA The University of Arizona Tucson AZ USA University of Alberta Edmonton AB Canada

综述近年来作者对单变量土壤水分演变模式和由作者提出的几种大气和植被生态及土壤系统水文过程相互作用模式 (给定植被冠层的三层相互作用模式、土壤和植被生态水文相互作用的三变量模式和五变量模式 )所作的理论分析和数值模拟的结果 ... 详细信息

综述近年来作者对单变量土壤水分演变模式和由作者提出的几种大气和植被生态及土壤系统水文过程相互作用模式 (给定植被冠层的三层相互作用模式、土壤和植被生态水文相互作用的三变量模式和五变量模式 )所作的理论分析和数值模拟的结果 ,鲜明和简洁地显示出这些模式能抓住这个复杂的系统最本质最基本的特征。在给定的大气状态情况下 ,这个复杂系统具有鲜明的多时间尺度现象、对输入响应的频率“红移”现象、多平衡态和极限环、分叉、突变、自组织过程、再生现象、“沙漠化”和混沌现象 ,这些都在实际中得到验证。特别是作者提出的植被 (尤其是枯落物 )“遮蔽机制”的减弱可能是过度放牧导致沙漠化在短期内就显效的主要原因 ,而在很长期间或气候变迁所导致的沙漠化过程中 ,则它和Charney提出的“反照率机制”可能同时起作用 ,建议作进一步的数值模拟加以验证。作者还提出了对响应特征时间尺度第一近似进行修正的方法。

关键词：水文过程大气植被冠层反照率响应特征多时间尺度沙漠化土壤系统枯落物定植

Multi-Scale Dilated Convolution Network for SPeCT-MPI Cardiovascular Disease Classification with Adaptive Denoising and Attenuation Correction

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Computer Modeling in engineering & Sciences 2025年第1期142卷 299-327页

作者： A.robert Singh Suganya Athisayamani Gyanendra Prasad Joshi Bhanu Shrestha Department of Computational Intelligence SRM Institute of Science and TechnologyKattankulathur603203Tamil NaduIndia School of Computing Sastra Deemed to be UniversityThanjavur613401Tamil NaduIndia Department of Artificial Intelligence&Software Kangwon National UniversitySamcheok25913Republic of Korea Department of Information Convergence System Graduate School of Smart ConvergenceKwangwoon UniversitySeoul01897Republic of Korea

Myocardial perfusion imaging(MPI),which uses single-photon emission computed tomography(SPeCT),is a well-known estimating tool for medical diagnosis,employing the classification of images to show situations in coronary artery disease(CAD).The automatic classification of SPeCT images for different techniques has achieved near-optimal accuracy when using convolutional neural networks(CNNs).This paper uses a SPeCT classification framework with three steps:1)Image denoising,2)Attenuation correction,and 3)Image *** denoising is done by a U-Net architecture that ensures effective image *** correction is implemented by a convolution neural network model that can remove the attenuation that affects the feature extraction process of ***,a novel multi-scale diluted convolution(MSDC)network is *** merges the features extracted in different scales and makes the model learn the features more *** scales of filters with size 3×3 are used to extract *** three steps are compared with state-of-the-art *** proposed denoising architecture ensures a high-quality image with the highest peak signal-to-noise ratio(PSNR)value of *** proposed classification method is compared with the five different CNN models,and the proposed method ensures better classification with an accuracy of 96%,precision of 87%,sensitivity of 87%,specificity of 89%,and F1-score of 87%.To demonstrate the importance of preprocessing,the classification model was analyzed without denoising and attenuation correction.

关键词： SPeCT-MPI CAD MSDC denoising attenuation correction classification

Three-Stage Transfer Learning with AlexNet50 for MRI Image Multi-Class Classification with Optimal Learning Rate

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Computer Modeling in engineering & Sciences 2025年第1期142卷 155-183页

作者： Suganya Athisayamani A.robert Singh Gyanendra Prasad Joshi Woong Cho School of Computing Sastra Deemed to be UniversityThanjavur613401India Department of Computational Intelligence SRM Institute of Science and TechnologyKattankulathur603203India Department of AI and Software engineering Kangwon National UniversitySamcheok25913Republic of Korea Department of electronics Information and Communication EngineeringKangwon National UniversitySamcheok25913Republic of Korea

In radiology,magnetic resonance imaging(MRI)is an essential diagnostic tool that provides detailed images of a patient’s anatomical and physiological *** is particularly effective for detecting soft tissue ***,radiologists manually interpret these images,which can be labor-intensive and time-consuming due to the vast amount of *** address this challenge,machine learning,and deep learning approaches can be utilized to improve the accuracy and efficiency of anomaly detection in MRI *** manuscript presents the use of the Deep AlexNet50 model for MRI classification with discriminative learning *** are three stages for learning;in the first stage,the whole dataset is used to learn the *** the second stage,some layers of AlexNet50 are frozen with an augmented dataset,and in the third stage,AlexNet50 with an augmented dataset with the augmented *** method used three publicly available MRI classification datasets:Harvard whole brain atlas(HWBA-dataset),the School of Biomedical engineering of Southern Medical University(SMU-dataset),and The National Institute of Neuroscience and Hospitals brain MRI dataset(NINS-dataset)for *** hyperparameter optimizers like Adam,stochastic gradient descent(SGD),Root mean square propagation(RMS prop),Adamax,and AdamW have been used to compare the performance of the learning ***-dataset registers maximum classification *** evaluated the performance of the proposed classification model using several quantitative metrics,achieving an average accuracy of 98%.

关键词： MRI tumors classification AlexNet50 transfer learning hyperparameter tuning optimizer

Human endogenous retrovirus type-W and multiple sclerosis–related smoldering neuroinflammation

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Neural Regeneration Research 2025年第3期20卷 813-814页

作者： Joel Gruchot Laura Reiche Andrew Chan robert Hoepner Patrick Küry Department of Neurology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neurology InselspitalBern University Hospital and University of BernBernSwitzerland

Introduction to human endogenous retrovirus type-W(HeRV-W): Genomic inheritance from the past includes retroviral sequences that have been stably incorporated into our genomes and account for up to 8% of human DNA.

关键词： endogenous inflammation Human

Lipid droplets in the nervous system:involvement in cell metabolic homeostasis

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Neural Regeneration Research 2025年第3期20卷 740-750页

作者： Yuchen Zhang Yiqing Chen Cheng Zhuang Jingxuan Qi robert Chunhua Zhao Jiao Wang School of Life Sciences Shanghai UniversityShanghaiChina School of Medicine Shanghai UniversityShanghaiChina Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic MedicinePeking Union Medical CollegeBeijingChina Center of excellence in Tissue engineering Chinese Academy of Medical SciencesBeijingChina Beijing Key Laboratory of New Drug Development and Clinical Trial of Stem Cell Therapy BeijingChina

Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous *** droplet formation begins with the synthesis of neutral lipids in the endoplasmic ***,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous *** addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress ***,lipid droplets exhibit specific functions in neurons and glial *** of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system *** review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and ***,it will explore the association between lipid droplets and neurodegenerative *** the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

关键词： Alzheimer's disease lipid droplet biogenesis lipid droplets lipid metabolism nervous system neurodegenerative disorders oxidative stress Parkinson's disease

Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen robert J.Thomas M.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

Climate Change:No Going Back

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China Today 2025年第1期74卷 42-44页

作者： robert WALKeR Beijing Normal University Royal Society of Arts Academy of Social Sciences in the U.K

With a commitment to reduce emissions,and its investment in green technology bringing down global costs,China is emerging as the leader in fighting climate *** knows that our world is getting *** also know *** out po... 详细信息

关键词： investment bringing fighting