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Vegetation change as related to terrain factors at two glacier forefronts, Glacier National Park, Montana, U.S.A.

Journal of Mountain Science 2020年第1期17卷 1-15页

作者： Callie B.LAMBErT Lynn M・rESLEr Yang SHAO david r.butler Department of Geography Virginia Tech220 Stanger StreetBlacksburgVA24061USA Texas State University Department of GeographySan MarcosTX 78666USA

Glacier recession is a globally occurring trend. Although a rich body of work has documented glacial response to climate warming, few studies have assessed vegetation cover change in recently deglaciated areas, especially using geospatial technologies. Here, vegetation change at two glacier forefronts in Glacier National Park, Montana, *** quantified through remote sensing analysis,fieldwork validation, and statistical ***, we assessed the spatial and temporal patterns of landcover change at the two glacier forefronts in Glacier National Park and determined the role of selected biophysical terrain factors(elevation, slope, aspect, solar radiation, flow accumulation, topographic wetness index, and surficial geology) on vegetation change(from nonvegetated to vegetated cover) at the deglaciated *** imagery of the study locations in 1991, 2003,and 2015 were classified and validated using visual interpretation. Model results revealed geographic differences in biophysical correlates of vegetation change between the study areas, suggesting that terrain variation is a key factor affecting spatialtemporal patterns of vegetation change. At Jackson Glacier forefront, increases in vegetation over some portion or all of the study period were negatively associated with elevation, slope angle, and consolidated bedrock. At Grinnell Glacier forefront,increases in vegetation associated negatively with elevation and positively with solar *** geospatial and field approaches to the study of vegetation change in recently deglaciated terrain are recommended to understand and monitor processes and patterns of ongoing habitat change in rapidly changing mountain environments.

关键词： Land cover change Physical geography Glacial forefronts Vegetation change Glacier National Park Terrain factors

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自然地理学中的混沌理论

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地理译报 1992年第4期11卷 5-9页

作者： George P.Malanson david r.butler Stephen J.Walsh 王云才朱登兴宫新荷

混沌是表述无序中的有序的一个概念:简单确定性系统能产生不可预见的、看起来似乎是些盲目的结果。混沌的概念产生于对非线性动态系统的研究:这类系统代表了大多数自然地理学中的系统。现在系统论作为自然地理学中的理论已被人们广泛接... 详细信息

混沌是表述无序中的有序的一个概念:简单确定性系统能产生不可预见的、看起来似乎是些盲目的结果。混沌的概念产生于对非线性动态系统的研究:这类系统代表了大多数自然地理学中的系统。现在系统论作为自然地理学中的理论已被人们广泛接受,但是“非线性”这一概念并非如此。在自然科学中,由于混沌理论愈来愈引起人们的注意。

关键词：自然地理学混沌理论

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Data-driven systematic analysis of waterborne viruses and health risks during the wastewater reclamation process

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Environmental Science and Ecotechnology 2024年第3期19卷 80-90页

作者： Jia-Xin Ma Xu Wang Yi-rong Pan Zhao-Yue Wang Xuesong Guo Junxin Liu Nan-Qi ren david butler research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing100085China State Key Laboratory of UrbanWater resource and Environment School of Civil and Environmental EngineeringHarbin Institute of TechnologyShenzhenShenzhen518055China University of Chinese Academy of Sciences Beijing100049China Centre for Water Systems College of EngineeringMathematics and Physical SciencesUniversity of ExeterExeterEX44QFUnited Kingdom

Waterborne viral epidemics are a major threat to public *** interest in wastewater reclamation highlights the importance of understanding the health risks associated with potential microbial hazards,particularly for reused water in direct contact with *** study focused on identifying viral epidemic patterns in municipal wastewater reused for recreational applications based on long-term,spatially explicit global literature data during 2000e2021,and modelled human health risks from multiple exposure pathways using a well-established quantitative microbial risk assessment *** median viral loads in municipal wastewater ranged from 7.92×10^(4)to 1.4×10^(6)GC L^(-1)in the following ascending order:human adenovirus(HAdV),norovirus(NoV)GII,enterovirus(EV),NoV GI,rotavirus(rV),and severe acute respiratory syndrome coronavirus 2(SArSCoV-2).Following secondary or tertiary wastewater treatment,NoV GI,NoV GII,EV,and rV showed a relatively higher and more stable log reduction value with medians all above 0.8(84%),whereas SArSCoV-2 and HAdV showed a relatively lower reduction,with medians ranging from 0.33(53%)to 0.55(72%).A subsequent disinfection process effectively enhanced viral removal to over 0.89-log(87%).The predicted event probability of virus-related gastrointestinal illness and acute febrile respiratory illnesses in reclaimed recreational water exceeded the World Health Organization recommended recreational risk benchmark(5%and 1.9%,respectively).Overall,our results provided insights on health risks associated with reusing wastewater for recreational purposes and highlighted the need for establishing a regulatory framework ensuring the safety management of reclaimed waters.

关键词： reclaimed water Waterborne virus recreational Human health Data-driven analysis

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Soil security and global food security

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 297-302页

作者： david r.MONTGOMErY Department of Earth and Space Sciences University of Washington townSeattleWA 98105USA

Over the course of the postglacial period has managed to add degrade a substantial portion of the world's potential agricultural land. The soil loss and degradation that has repeatedly impacted regional societies around the world resulted from agricultural practices that increased the physical loss of soil(erosion), reduced soil organic matter, changed p H(acidification) or salinity,and disrupted or altered communities of soil life. In the coming century, as continued soil degradation threatens global food security while the global population keeps rising it is imperative that farmers develop and adopt soilhealth building(regenerative) practices to solve a problem that has plagued societies throughout history. Growing evidence suggests that agricultural systems that combine cover crops, reduced tillage, and diverse crop rotations can reduce erosion, enhance soil health and rebuild soil organic matter to cultivate beneficial soil life and harvest both economic and environmental benefits. In the coming post-oil world, global food security would benefit from a global effort to promote soil restoration to help addresses the challenge of sustainably feeding the world, increase soil-based carbon sequestration,protect on-farm biodiversity and reduce off-farm water pollution. Because soil security sets a solid foundation for global food security, agricultural policies and subsidies should be reformed to encourage farmers to adopt regenerative,soil-building practices.

关键词： Agriculture soil security food security regenerative

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Comparison of the timing of spring phenological events between phenological garden trees and wild populations

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Journal of Plant Ecology 2024年第2期17卷 49-61页

作者： Calum J.Sweeney Fidelma butler Astrid Wingler School of Biological Earth&Environmental Sciences and Environmental Research InstituteUniversity College CorkDistillery FieldsNorth MallCork T23 TK30Ireland

Phenological research is engaged in monitoring the infuence of climate change on the natural *** International Phenological Gardens(IPG)network provides a valuable dataset of standardized tree phenology records dating back to the mid-20th *** make best use of this actively growing record,it is important to investigate how network data can be applied to predict the timing of phenological events in natural *** study compared clonally propagated IPG downy birch(Betula pubescens Ehrh.)and hazel(Corylus avellana L.)specimens of central European provenance to nearby wild populations at the western-most margin of the IPG network,in the south-west of *** addition to monitoring by trained scientists,observations by citizen scientists were *** order of the timing of phenological events among sites was consistent across 2 years,confrming reproducibility of the *** trees had the earliest *** leaf unfolding and *** fowering dates of the sites *** addition,leaf unfolding occurred later in the wild populations than expected from the temperature responses of the *** and *** IPG *** variation in phenology also exceeded the historical change observed at the IPG site,suggesting a potential genetic basis for climate *** circumference,refecting the age-dependent increase in tree size,was found to infuence *** phenology,with earlier timing of phenological events in larger *** fnding highlights tree size as an important consideration in the management of phenological gardens and tree phenology research in general.

关键词： citizen science downy birch(Betula pubescens) hazel(Corylus avellana) phenological garden spring phenology tree size

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Hybrid LES/rANS Simulations of Compressible Flow in a Linear Cascade of Flat Blade Profiles

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Journal of Thermal Science 2024年第5期33卷 1839-1850页

作者： Jaromír PrIHODA Petr STrAKA david SIMUrDA Petr SIDLOF Jan LEPICOVSKY Institute of Thermomechanics of the Czech Academy of Sciences Dolejskova 1402/518200 Prague 5Czech Republic Aerospace research and Test Centre Beranovych 13019905 PragueCzech Republic Technical University of Liberec Faculty of MechatronicsStudentska 246117 Liberec 1Czech Republic

The paper reports on 3D numerical simulations of unsteady compressible airflow in a blade cascade consisting of flat profiles using a hybrid LES/rANS approach including a transition *** a first step towards simulation of blade flutter in turbomachinery,various incidence angle offsets of the middle blade were *** simulations were run for the flow regime characterized by outlet isentropic Mach number M_(is)=0.5and zero *** results of the LES/rANS simulations(pressure and Mach number distributions)were compared to a baseline rANS model,and to experimental data measured in a high-speed wind *** numerical results show that both methods overpredict flow separation taking place at the leading *** this regard,the hybrid LES/rANS method does not provide superior results compared to the traditional rANS ***,the LES/rANS results also capture vortex shedding from the blunt trailing *** frequency of the trailing edge vortex shedding in CFD simulations matches perfectly the spectral peak recorded during wind tunnel measurements.

关键词： numerical simulation blade cascade hybrid LES/rANS

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Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony r.J.Kucernak david Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOr).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOr activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOr arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

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real-world clinical efficacy of tofacitinib in moderate-to-severe ulcerative colitis

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World Journal of Gastroenterology 2024年第34期30卷 3929-3931页

作者： Sara r Lopes Claudio Martins Madalena Teixeira david Tomás Department of Gastroenterology Unidade Local de Saúde da Arrábida-Hospital de São BernardoSetúbal 2910-446Portugal

Tofacitinib is an oral small-molecule Janus kinase(JAK)inhibitor that preferentially inhibits JAK1 and *** efficacy in inducing and maintaining remission in ulcerative colitis(UC)as well as its safety profile has been demonstrated in multicenter,randomized,double-blind,placebo-controlled ***,real-world studies evaluating the effectiveness and adverse effects of tofacitinib have been conducted,affirming its clinical efficacy in moderate-to-severe UC.

关键词： Ulcerative colitis Tofacitinib real-world studies Inflammatory bowel disease Janus kinase inhibitor

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Late Ordovician Mass Extinction: Earth, fire and ice

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National Science review 2024年第1期11卷 51-65页

作者： david A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

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One-dimensional monotone nonautonomous dynamical systems

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Science China Mathematics 2024年第2期67卷 281-314页

作者： david Cheban Faculty of Mathematics and Computer Science Laboratory of Fundamental and Applied MathematicsMoldova State UniversityChisinau 2009Moldova

This work is devoted to the study of the dynamics of one-dimensional monotone nonautonomous(cocycle) dynamical systems. A description of the structures of their invariant sets, omega limit sets,Bohr/Levitan almost periodic and almost automorphic motions, global attractors, and pinched and minimalsets is given. An application of our general results is given to scalar differential and difference equations.

关键词： one-dimensional dynamics pinched and minimal sets global attractors monotone nonautonomous cocycle almost periodic solutions scalar differential/difference equations

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