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High Spatial Resolution and High Temporal Frequency(30-m/15-day) Fractional Vegetation Cover Estimation over China Using Multiple Remote Sensing Datasets:Method Development and Validation

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Journal of Meteorological Research 2021年第1期35卷 128-147页

作者： Xihan MU Tian ZHAO Gaiyan RUAN Jinling SONG Jindi WANG Guangjian YAN tim rmcvicar Kai YAN Zhan GAO Yaokai LIU Yuanyuan WANG State Key Laboratory of Remote Sensing Science Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Beijing Engineering Research Center for Global Land Remote Sensing Products Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China CSIRO Land and Water ACT2601Australia Department of Earth and Environment Boston UniversityBostonMA 02215USA Jiangsu Institute of Urban Planning and Design Nanjing 210036China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081China

High spatial resolution and high temporal frequency fractional vegetation cover(FVC) products have been increasingly in demand to monitor and research land surface processes. This paper develops an algorithm to estimate FVC at a 30-m/15-day resolution over China by taking advantage of the spatial and temporal information from different types of sensors: the 30-m resolution sensor on the Chinese environment satellite(HJ-1) and the 1-km Moderate Resolution Imaging Spectroradiometer(MODIS). The algorithm was implemented for each main vegetation class and each land cover type over China. First, the high spatial resolution and high temporal frequency normalized difference vegetation index(NDVI) was acquired by using the continuous correction(CC) data assimilation method. Then, FVC was generated with a nonlinear pixel unmixing model. Model coefficients were obtained by statistical analysis of the MODIS NDVI. The proposed method was evaluated based on in situ FVC measurements and a global FVC product(GEOV1 FVC). Direct validation using in situ measurements at 97 sampling plots per half month in 2010 showed that the annual mean errors(MEs) of forest, cropland, and grassland were-0.025, 0.133, and 0.160, respectively, indicating that the FVCs derived from the proposed algorithm were consistent with ground measurements [R2 = 0.809,root-mean-square deviation(RMSD) = 0.065]. An intercomparison between the proposed FVC and GEOV1 FVC demonstrated that the two products had good spatial–temporal consistency and similar magnitude(RMSD approximates 0.1). Overall, the approach provides a new operational way to estimate high spatial resolution and high temporal frequency FVC from multiple remote sensing datasets.

关键词： fractional vegetation cover(FVC) high spatial resolution and high temporal frequency data fusion normalized difference vegetation index(NDVI) pixel unmixing model multiple remote sensing datasets

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Variability and trends of near-surface wind speed over the Tibetan Plateau:The role played by the westerly and Asian monsoon

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Advances in Climate Change Research 2024年第3期15卷 525-536页

作者： Gang-Feng ZHANG Cesar AZORIN-MOLINA Deliang CHEN tim rmcvicar Jose AGUIJARRO Kai-Qiang DENG Lorenzo MINOLA Jaeyeon LEE Seok-Woo SON Heng MA Pei-Jun SHI State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Engineering Center of Desertification and Blown-Sand Control of Ministry of Education Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education Beijing Normal UniversityBeijing 100875China Centro de Investigaciones Sobre Desertificaci'on Consejo Superior de Investigaciones Cientı'ficas(CIDECSIC-UV-Generalitat alenciana)ClimateAtmosphere and Ocean Laboratory(Climatoc-Lab)Moncada 46113Spain Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden CSIRO Environment CanberraACT 2600Australia Australian Research Council Centre of Excellence for Climate Extremes CanberraACT 2600Australia State Meteorological Agency Balearic Islands OfficePalma de Mallorca 07015Spain School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 519082China Interuniversity Department of Regional and Urban Studies and Planning(DIST) Politecnico and University of TurinTurin 10125Italy School of Earth and Environmental Sciences Seoul National UniversitySeoul 08826South Korea Atmospheric and Oceanic Sciences Program Princeton UniversityPrinceton NJ 08544USA Geophysical Fluid Dynamics Laboratory NOAAPrinceton NJ 08544USA

Near-surface wind speed exerts profound impacts on many environmental issues,while the long-term(≥60 years)trend and multidecadal variability in the wind speed and its underlying causes in global high-elevation and mountainous areas(e.g.,Tibetan Plateau)remain largely ***,by examining homogenized wind speed data from 104 meteorological stations over the Tibetan Plateau for 1961-2020 and ERA5 reanalysis datasets,we investigated the variability and long-term trend in the near-surface wind speed and revealed the role played by the westerly and Asian *** results show that the homogenized annual wind speed displays a decreasing trend(-0.091 m s^(−1)per decade,p<0.05),with the strongest in spring(-0.131 m s^(−1)per decade,p<0.05),and the weakest in autumn(-0.071 m s^(−1)per decade,p<0.05).There is a distinct multidecadal variability of wind speed,which manifested in an prominent increase in 1961-1970,a sustained decrease in 1970-2002,and a consistent increase in *** observed decadal variations are likely linked to large-scale atmospheric circulation,and the correlation analysis unveiled a more important role of westerly and East Asian winter monsoon in modulating near-surface wind changes over the Tibetan *** potential physical processes associated with westerly and Asian monsoon changes are in concordance with wind speed change,in terms of overall weakened horizontal air flow(i.e.,geostrophic wind speed),declined vertical thermal and dynamic momentum transfer(i.e.,atmospheric stratification thermal instability and vertical wind shear),and varied Tibetan Plateau *** indicates that to varying degrees these processes may have contributed to the changes in near-surface wind speed over the Tibetan *** study has implications for wind power production and soil wind erosion prevention in the Tibetan Plateau.

关键词： Tibetan Plateau Wind speed Decadal change Atmospheric circulation Physical processes

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Like a G6-nal:transcriptional control of G-protein coupled receptors during oligodendroglial development

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Neural Regeneration Research 2025年第7期20卷 2001-2002页

作者： tim Aberle Michael Wegner Institut für Biochemie Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

Multilayered control of myelination:Quick,saltatory conduction of action potentials along nerve fibers requires the electrical insulation of axons by myelinating *** the central nervous system,this role is taken up by *** are marked by the expression of the lineage determinants Sox10 and Olig2 and arise from oligodendrocyte precursor cells(OPCs)during embryonal *** the majority of OPCs differentiate into mature oligodendrocytes when nearby axonal segments require myelination,a small subpopulation of OPCs persist as a progenitor ***,the timing of myelination and maintenance of the OPC pool both need to be precisely *** transcription factors either positively or negatively affect oligodendrocyte differentiation and maintenance of the OPC pool as components of a complex gene regulatory network(reviewed in Sock and Wegner,2021).Network activity is additionally influenced by extracellular signaling molecules that bind to receptors on the oligodendroglial cell surface and activate intracellular signaling *** the receptors are linked to the network is poorly understood so far,but pivotal to understanding the overall regulation of central nervous system(CNS)myelination in response to environmental *** insights were recently gained for Gpr37(Schmidt et al.,2024),a G-protein coupled receptor(GPCR)with known relevance in differentiating oligodendrocytes(Yang et al,2016).

关键词： gained insulation conduction

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Causes of Winter Persistent Extreme Cold Events in Northeastern China

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Advances in Atmospheric Sciences 2025年第4期42卷 780-793页

作者： Ming YANG Qingjiu GAO tim LI State Key Laboratory of Climate System Prediction and Risk Management/Key Laboratory of Meteorological Disaster Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China Department of Atmospheric Sciences University of Hawaii at ManoaHonoluluHI 96822USA

Persistent(5-day or longer)extreme cold events(ECEs)over northeastern China during the boreal winter of 1979–2020 are investigated using daily minimum temperature(Tmin)from the China Meteorological Data *** extreme cooling area and intensity indices associated with the ECEs exhibit a dominant 10–40-day periodicity,indicating a close link with atmospheric intraseasonal oscillations(ISOs).The ECEs are categorized into W-and *** the former,the low-frequency cooling associated with the ISO first penetrates into the western boundary of the northeastern China domain and later occupies the entire domain at its peak *** upper-tropospheric circulation associated with this type is characterized by a northwest–southeast-oriented Rossby wave train,expanding from the Ural Mountains to the western Pacific *** the latter,the cooling invades the northern boundary first and then penetrates into the entire *** upper tropospheric precursory signal associated with this type is a zonally oriented negative geopotential height anomaly,which slowly moves southward.A downward-propagating signal is observed in the stratospheric potential vorticity field prior to the peak cooling,implying a possible stratospheric *** addition to the W-and N-types,ECEs can also occur in a localized region near either at the northern or southern boundary of the domain.

关键词： extreme cold events low-frequency ISO mode Rossby wave train composite analysis downward propagation potential vorticity

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Insights from an academic endeavor into central nervous system drug discovery

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Neural Regeneration Research 2025年第6期20卷 1717-1718页

作者： Lieve van Veggel An M.Voets tim Vanmierlo Rudy Schreiber BIOMED Biomedical Research Institute Faculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry and Neuropsychology Division of Translational NeuroscienceEuropean Graduate School of NeuroscienceSchool for Mental Health and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands Section of Psychopharmacology Neuropsychology and PsychopharmacologyFaculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands University MS Center(UMSC) Hasselt-PeltBelgium

Historically,"big pharma"did most central nervous system drug discovery R&D ***,in modern times their"management reductionism"resulted in disappointing pipelines and pharma resided to(late)development,regulatory approval,and marketing(Thong,2015).This had significant consequences for financing and executing research,resulting in a larger role for funding by governments and patient-organizations and a shift of research to academia(Mazzucato,2013).

关键词： academic approval consequences

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Effect of dietary fibre on the gastrointestinal microbiota during critical illness:A scoping review

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World Journal of Critical Care Medicine 2025年第1期14卷 49-59页

作者： Angajendra N Ghosh Calum J Walsh Matthew J Maiden tim P Stinear Adam M Deane Department of Intensive Care The Northern HospitalEpping 3076VictoriaAustralia Department of Microbiology and Immunology The Peter Doherty Institute for Infection and ImmunityMelbourne 3052VictoriaAustralia Department of Intensive Care The Royal Melbourne HospitalThe University of MelbourneParkville 3050VictoriaAustralia Department of Intensive Care Medicine The Royal Melbourne HospitalParkville 3050VictoriaAustralia

The systemic effects of gastrointestinal(GI)microbiota in health and during chronic diseases is increasingly *** strategies to modulate the GI microbiota during chronic diseases have demonstrated *** changes in dietary intake can rapidly change the GI microbiota,the impact of dietary changes during acute critical illness on the microbiota remain *** fibre is metabolised by carbohydrate-active enzymes and,in health,can alter GI *** aim of this scoping review was to describe the effects of dietary fibre supplementation in health and disease states,specifically during critical *** controlled trials and prospective cohort studies that include adults(>18 years age)and reported changes to GI microbiota as one of the study outcomes using non-culture methods,were *** show dietary fibres have an impact on faecal microbiota in health and *** fibre,inulin,has a marked and specific effect on increasing the abundance of faecal *** chain fatty acids produced by Bifidobacteria have been shown to be beneficial in other patient *** few trials have evaluated the effect of dietary fibre on the GI microbiota during critical *** research is necessary to establish optimal fibre type,doses,duration of intervention in critical illness.

关键词： Gastrointestinal microbiota Dietary fibre Health Critical illness Short chain fatty acids

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Causes of Winter Persistent Extreme Cold Events in Northeastern China

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Advances in Atmospheric Sciences 2025年第4期 780-793页

作者： Ming YANG Qingjiu GAO tim LI State Key Laboratory of Climate System Prediction and Risk Management/Key Laboratory of Meteorological Disaster Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and Technology Department of Atmospheric Sciences University of Hawaii at Manoa

Persistent（5-day or longer） extreme cold events（ECEs） over northeastern China during the boreal winter of1979–2020 are investigated using daily minimum temperature(Tmin) from the China Meteorological Data Network. The extreme cooling area and intensity indices associated with the ECEs exhibit a dominant 10–40-day periodicity, indicating a close link with atmospheric intraseasonal oscillations（ISOs）. The ECEs are categorized into W-and N-type. In the former,the low-frequency cooling associated with the ISO first penetrates into the western boundary of the northeastern China domain and later occupies the entire domain at its peak phase. The upper-tropospheric circulation associated with this type is characterized by a northwest–southeast-oriented Rossby wave train, expanding from the Ural Mountains to the western Pacific Ocean. In the latter, the cooling invades the northern boundary first and then penetrates into the entire domain. The upper tropospheric precursory signal associated with this type is a zonally oriented negative geopotential height anomaly,which slowly moves southward. A downward-propagating signal is observed in the stratospheric potential vorticity field prior to the peak cooling, implying a possible stratospheric impact. In addition to the W-and N-types, ECEs can also occur in a localized region near either at the northern or southern boundary of the domain.

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Solvable base change and Rankin-Selberg convolutions

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Science China Mathematics 2017年第1期60卷 99-112页

作者： GILLESPIE tim Department of Mathematics St. Ambrose University Davenport IA 52803 USA

Let π and π′ be unitary automorphic cuspidal representations of GL_n(A_E) and GL_m(A_F), and let E and F be solvable Galois extensions of Q of degrees ? and ?′, respectively. Using the fact that the automorphic induction and base change maps exist for E and F, and assuming an invariance condition under the actions of the Galois groups, we attach to the pair(π, π′) a Rankin-Selberg L-function L(s, π×E,Fπ′) for which we prove a prime number theorem. This gives a method for comparing two representations that could be defined over completely different extensions, and the main results give a measure of how many cuspidal components the two representations π and π′ have in common when automorphically induced down to the rational numbers. The proof uses the structure of the Galois group of the composite extension EF and the character groups attached to the fields via class field theory. The second main theorem also gives an indication of when the base change of π up to the composite extension EF remains cuspidal.

关键词： automorphic L-function base change automorphic induction

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Antipredator deception in terrestrial vertebrates

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Current Zoology 2014年第1期60卷 16-25页

作者： tim CARO Department of Wildlife Fish and Conservation Biology and Center of Population Biology University of California Davis CA95616 USA

Abstract Deceptive antipredator defense mechanisms fall into three categories： depriving predators of knowledge of prey＇s presence, providing cues that deceive predators about prey handling, and dishonest signaling. Deceptive defenses in terrestrial vertebrates include aspects of crypsis such as background matching and countershading, visual and acoustic Batesian mimicry, active defenses that make animals seem more difficult to handle such as increase in apparent size and threats, feigning injury and death, distractive behaviours, and aspects of flight. After reviewing these defenses, I attempt a preliminary evaluation of which aspects of antipredator deception are most widespread in amphibians, reptiles, mammals and birds

关键词： Amphibians Birds Defenses Dishonesty Mammals Prey Reptiles

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Male circumcision： towards a World Health Organisation normative practice in resource limited settings

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Asian Journal of Andrology 2010年第5期12卷 628-638页

作者： tim Hargreave Senior Fellow School of Clinical Science Edinburgh University Scotland UK Technical Adviser to the WHO RHR -HRP Africa HIV Prevention Male Circumcision Programme

There is now grade 1 evidence that male circumcision （MC） reduces the risk of a man acquiring HIV. Modelling studies indicate MC could in the next 10 years save up to 2 million lives in those African countries with high HIV prevalence. Several African countries are now scaling up public health MC programmes. The most effective immediate public health MC programmes in Africa will need to target 18-20 years old men. In the longer term there is a need for infant circumcision programmes. In order to implement more widespread MC there is a need to make the surgical procedures as simple as possible so that safe operations can be performed by paramedical staff. The WHO Manual of Male Circumcision under local anaesthetic was written with these objectives in mind. Included in the manual are three adult techniques and four paediatric procedures. The adult procedures are the dorsal slit, the for- ceps guided and the sleeve resection methods. Paediatric methods included are the plastibell technique, the Mogen and Gomco shield method and a standard surgical dorsal slit procedure. Each method is described in a step by step manner with photographic and line drawing illustrations. In addition to the WHO manual of surgical technique a teaching course has been developed and using this course it has been possible in one week to train a circumcision surgeon who has had no or minimal previous surgical experience. Further scaling will require training of circumcision surgeons, monitoring performance, training the trainer workshops as well as advocacy at national, international and government meetings. In addition to proceeding with standardised methods work is in progress to assess novel techniques in adults such as stay on ring devices and policies are being formulated as to how to assess new devices. Also work is in progress to explore efficiencies in surgical processing by task sharing. Proper informed consent and safety remain paramount and great care has to be taken as programmes in

关键词： Africa HIV male circumcision

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