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Machine learning-based prediction of sand and dust storm sources in arid Central Asia

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International Journal of Digital Earth 2023年第1期16卷 1530-1550页

作者： Wei Wang Alim Samat Jilili Abuduwaili Philippe De Maeyer tim Van de Voorde State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqiPeople’s Republic of China Research Centre for Ecology and Environment of Central Asia Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqiPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Department of Geography Ghent UniversityGhentBelgium Sino-Belgian Joint Laboratory of Geo-Information GhentBelgium Sino-Belgian Joint Laboratory of Geo-Information UrumqiPeople’s Republic of China

With the emergence of multisource data and the development of cloud computing platforms,accurate prediction of event-scale dust source regions based on machine learning(ML)methods should be considered,especially accounting for the temporal variability in sample and predictor *** Central Asia(ACA)is recognized as one of the world’s primary potential sand and dust storm(SDS)*** this study,based on the Google Earth Engine(GEE)platform,four ML methods were used for SDS source prediction in *** meteorological and terrestrial factors were selected as influencing factors controlling SDS source susceptibility and applied in the modeling ***,the results revealed that the random forest(RF)algorithm performed best,followed by the gradient boosting tree(GBT),maximum entropy(MaxEnt)model and support vector machine(SVM).The Gini impurity index results of the RF model indicated that the wind speed played the most important role in SDS source prediction,followed by the normalized difference vegetation index(NDVI).This study could facilitate the development of programs to reduce SDS risks in arid and semiarid regions,particularly in ACA.

关键词： Susceptibility mapping event scale google earth engine(GEE) remote sensing

Evaluation of freezing state of sandstone using ultrasonic time-frequency characteristics

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 584-599页

作者： Jiwei Zhang Julian Murton tim Cane Vikram Maji Lili Sui Shujie Liu Song Zhang University of Science and Technology Beijing Beijing100083China Permafrost Laboratory Department of GeographyUniversity of SussexBrightonBN19QJUK Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing100083China Department of Earth Sciences Indian Institute of Technology KanpurKanpurIndia North China University of Technology Beijing100041China

Common problems in engineering projects that involve artificial ground freezing of soil or rock include inadequate thickness,strength and continuity of artificial frozen *** is difficult to evaluate the freezing state using only a few thermometer holes at fixed positions or with other existing *** we report a novel experimental design that investigates changes in ultrasonic properties(received waveform,wave velocity V_(p),wave amplitude,frequency spectrum,centroid frequency f_(c),kurtosis of the frequency spectrum KFS,and quality factor Q)measured during upward freezing,compared with those during uniform freezing,in order to determine the freezing state in 150 mm cubic blocks of Ardingly *** content,porosity and density were estimated during upward freezing to ascertain water migration and changes of porosity and density at different *** period of receiving the wave increased substantially and coda waves changed from loose to compact during both upward and uniform *** trend of increasing V_(p) can be divided into three stages during uniform *** upward freezing,V_(p) increased more or less *** frequency spectrum could be used as a convenient and rapid method to identify different freezing states of sandstone(unfrozen,upward frozen,and uniformly frozen).The continuous changes in reflection coefficient r_(φ),refraction coefficient t_(φ) and acoustic impedance field are the major reason for larger reflection and refraction during upward freezing compared with uniform *** velocity V_(p),wave amplitude A_(h),centroid frequency f_(c) and quality factor Q were adopted as ultrasonic parameters to evaluate quantitatively the temperature T of uniformly frozen sandstone,and their application within a radar chart is *** of V_(p) provides a convenient method to evaluate the freezing state and calculate the cryofront height and frozen section thickness of upward frozen sandstone,with

关键词： Frozen sandstone Uniform freezing Upward freezing Ultrasonic testing Freezing state

Antigen unmasking does not improve the visualization of phospholipase C zeta in human spermatozoa

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Asian Journal of Andrology 2022年第4期24卷 345-352页

作者： Xin Meng Celine Jones Pedro Melo Caroline Ross Ginny Mounce tim Child Kevin Coward Nuffield Department of Women's and Reproductive Health University of OxfordOxford OX39DUUK The Women's Centre Oxford University Hospitals NHS Foundation TrustOxford OX39DUUK xford Fertility Oxford Business Park NorthOxford OX42HWUK.

Phospholipase C zeta(PLCζ)is a sperm-specific protein that triggers oocyte *** analysis of PLCζexpression in human spermatozoa can be used as a diagnostic marker for oocyte activation *** laboratory has previously optimized a standard"in-house"assay to determine PLCζexpression in human ***,one study has suggested that an antigen unmasking method(AUM)would be more efficient in visualizing PLCζin human *** study aimed to compare our established assay and AUM(involving HCl,acidic Tyrode's solution[AT],and heat).The mean relative fluorescence(RF)intensity of PLCζin frozen-thawed spermatozoa from fourteen fertile donors stained with the in-house method was significantly higher than three other AUM groups(in-house[mean±standard error of mean]:18.87±2.39 arbitrary units[a.u.]vs non-AUM:11.44±1.61 a.u.,AT-AUM:12.38±1.89 a.u.,and HCl-AUM:12.51±2.16 a.u.,P<0.05,one-way analysis of variance).The mean RF intensity of PLCζin AT-and HCl-treated spermatozoa from 12 infertile males was not significantly different from that of the non-AUM ***,the in-house method resulted in the highest RF intensity(12.11±1.36 a.u.,P<0.01).Furthermore,specificity testing of antibody-antigen binding indicated that the in-house method showed more specific binding than spermatozoa treated by the *** conclusion,our in-house method showed superior visualization and reliability than the AUM,thus supporting the continued use of our in-house assay for clinical research screening.

关键词： antigen unmasking immunofluorescence staining male infertility phospholipase C zeta

Non-invasive Angiographic-based Fractional Flow Reserve:Technical Development,Clinical Implications,and Future Perspectives

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当代医学科学(英文) 2023年第3期43卷 423-433页

作者： Joyce Peper Michiel L.Bots tim Leiner Martin J.Swaans Department of Cardiology St.Antonius HospitalNieuwegein 3435 CMThe Netherlands Department of Radiology University Medical Center UtrechtUtrecht 3508 GAThe Netherlands Julius Center for Health Sciences and Primary Care University Medical Center UtrechtUtrecht 3584 CGThe Netherlands

New non-and less-invasive techniques have been developed to overcome the procedural and operator related burden of the fractional flow reserve(FFR)for the assessment of potentially significant stenosis in the coronary *** FFR-techniques can obviate the need for the additional flow or pressure wires as used for FFR *** review provides an overview of the developments and validation of the virtual FFR-algorithms,states the challenges,discusses the upcoming clinical trials,and postulates the future role of virtual FFR in the clinical practice.

关键词： coronary artery disease quantitative flow ratio fractional flow reserve diagnostic accuracy physiology guided percutaneous coronary intervention

Dominant species of mid-elevation grasslands of the uKhahlamba-Drakensberg Park are predicted to be largely immune to climate change

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山地科学学报(英文) 2023年第9期20卷 2468-2486页

作者： Debbie JEWITT Craig D.MORRIS tim G.O’CONNOR Michelle J.TEDDER Ezemvelo KZN Wildlife Scientific ServicesPO Box 13053Cascades 3202South Africa School of Animal Plant and Environmental SciencesUniversity of the WitwatersrandJohannesburgPrivate Bag X3WITS 2050South Africa Agricultural Research Council-Animal Production(ARC-AP) ℅School of Life Sciences University of KwaZulu-NatalPrivate Bag X01Scottsville 3209PietermaritzburgSouth Africa School of Life Sciences University of KwaZulu-NatalPrivate Bag X01Scottsville 3209PietermaritzburgSouth Africa

Anticipating global change impact on natural vegetation,especially in poorly researched systems,requires an understanding of the environmental factors that most strongly influence the organisation of plant communities at different *** environmental relations of plant communities in the Drakensberg mountains of South Africa remain poorly *** study investigated the influence of selected environmental determinants on the dominant species of plant community organisation in this *** order to provide an overview of the influence of the environment on botanical composition and plant diversity,this study,conducted as four discrete exercises,investigated the interplay of altitude,aspect and slope on the abundance of selected species,and to examine the influence of latitude,geological substrate and local topography on species *** diversity showed no pattern of response to investigated environmental *** composition was related to temperature and solarradiation *** altitude sites facing east were distinct for non-graminoid *** and latitude exerted a pronounced effect on species composition,confounded by longitude and precipitation *** substrate,in concert with slope steepness and orientation,influenced composition,restricting the abundance but not distribution of some *** individualistic responses were found for C_3,C_4,and non-graminoid species in relation to altitude,slope and *** and aspect mediate the effects of altitude and hence temperature for some *** study has demonstrated the complexity of drivers influencing species and compositional distribution in the Drakensberg and permits a preliminary consideration of potential changes in the composition and dominance structure of mid-elevation grasslands in response to climate *** dominant grass species were widespread across environmental gradients,occupying currently warm,cool,moist and dry habitats

关键词： Drakensberg Environmental gradients Grasslands Mountain biodiversity Vegetation

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鸟眼看世界

人与自然 2024年第5期 6-23页

作者：乔纳森·贝利蒂姆·弗拉克(摄影) 林肯(翻译) 不详

在广表无垠的天空中,鸟类以其独特的姿态书写着生命的华章。它们是天空的舞者,用灵动的身姿诠释着自然的韵律。本期跟随菲律宾鹰、吉祥仙鹤、红嘴鸥、巨嘴鸟等天空舞者的脚步,继续探索那神秘而又奇妙的鸟类王国,揭开鸟类世界的面纱,领... 详细信息

在广表无垠的天空中,鸟类以其独特的姿态书写着生命的华章。它们是天空的舞者,用灵动的身姿诠释着自然的韵律。本期跟随菲律宾鹰、吉祥仙鹤、红嘴鸥、巨嘴鸟等天空舞者的脚步,继续探索那神秘而又奇妙的鸟类王国,揭开鸟类世界的面纱,领略它们独特的魅力,共同守护这片美丽的天空家园。

关键词：红嘴鸥菲律宾鹰巨嘴鸟独特的魅力灵动鸟类舞者

A perspective on causality assessment in epigenetic research on neurodegenerative disorders

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Neural Regeneration Research 2023年第2期18卷 331-332页

作者： Philippos Koulousakis Assia Tiane Niels Hellings Jos Prickaerts Daniel van den Hove tim Vanmierlo Department of Psychiatry and Neuropsychology School for Mental Health and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands Department of Neuroscience Biomedical Research InstituteFaculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium University MS Center(UMSC)Hasselt-Pelt HasseltBelgium Department of Immunology and Infection Biomedical Research InstituteFaculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry Psychosomatics and PsychotherapyUniversity of WuerzburgWuerzburgGermany

Epigenetics refers to herita ble and reversible processes regulating gene expression that do not involve a change to the DNA *** modifications include DNA modifications(*** methylation a nd hydroxymethyl at ion),histo... 详细信息

关键词： degenerative sequence modification

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：可解 Galois扩张基础卷积第二基本定理伽罗瓦群 L-函数素数定理

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

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：陆生脊椎动物欺骗性防御机制食肉动物主动防御外观尺寸两栖动物爬行动物