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Climate and land-use change in wetlands:a dedication

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Ecosystem Health and Sustainability 2017年第9期3卷 1-3页

作者： Beth A.middleton U.S.Geological Survey Wetland and Aquatic Research CenterLafayetteLAUSA

Future climate and land-use change may wreak havoc on wetlands,with the potential to erode their values as harbors for biota and providers of human *** are important to protect,particularly because these provide a var... 详细信息

关键词： harbor change climate

Current and near-term advances in Earth observation for ecological applications

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Ecological Processes 2021年第1期10卷 1-57页

作者： Susan L.Ustin Elizabeth M.middleton John Muir Institute of the Environment University of CaliforniaDavisCA 95616USA NASA/Goddard Space Flight Center(Emerita) GreenbeltMD 20771USA.

there is an unprecedented array of new satellite technologies with capabilities for advancing our understanding of ecological processes and the changing composition of the Earth’s biosphere at scales from local plots to the whole *** identified 48 instruments and 13 platforms with multiple instruments that are of broad interest to the environmental sciences that either collected data in the 2000s,were recently launched,or are planned for launch in this *** have restricted our review to instruments that primarily observe terrestrial landscapes or coastal margins and are available under free and open data *** focused on imagers that passively measure wavelengths in the reflected solar and emitted thermal *** suite of instruments we describe measure land surface characteristics,including land cover,but provide a more detailed monitoring of ecosystems,plant communities,and even some species then possible from historic *** newer instruments have potential to greatly improve our understanding of ecosystem functional relationships among plant traits like leaf mass area(LMA),total nitrogen content,and leaf area index(LAI).they provide new information on physiological processes related to photosynthesis,transpiration and respiration,and stress detection,including capabilities to measure key plant and soil biophysical *** include canopy and soil temperature and emissivity,chlorophyll fluorescence,and biogeochemical contents like photosynthetic pigments(e.g.,chlorophylls,carotenoids,and phycobiliproteins from cyanobacteria),water,cellulose,lignin,and nitrogen in foliar *** data will enable us to quantify and characterize various soil properties such as iron content,several types of soil clays,organic matter,and other *** of these satellites are in low Earth orbit(LEO),but we include a few in geostationary orbit(GEO)because of their potential to measure plant physiological traits over diurnal periods,impro

关键词： terrestrial ecosystems Earth Observing Satellites Ecosystem processes Physiological functions Multispectral Hyperspectral thermal LiDAR Radar imagers Biochemistry Soil properties Species mapping Change detection 3D canopy structure topography

transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMRAN t.ASGHAR Z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

this paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. the influence of magnetic fields is also inspected in terms of their physical characteristics. to depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).the effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： hybrid nanofluid oscillating curved stretchable sheet gyrotactic microorganism Cattaneo-Christov heat and mass flux chemical reaction analytical solution O368

tracking desertification on the Mongolian steppe through NDVI and field-survey data

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International Journal of Digital Earth 2011年第1期4卷 50-64页

作者： troy Sternberg Renchin tsolmon Nicholas middleton David thomas School of Geography Oxford UniversitySouth Parks RoadOxford OX13QYUK UNESCO Remote Sensing Lab National University of MongoliaMain Building 1Bag Toru AvenueUlaan BaatarMongolia

Changing environmental and socio-economic conditions make land degradation,a major concern in Central and East *** satellite imagery,particularly Normalized Difference Vegetation Index(NDVI)data,has proved an effective tool for monitoring land cover *** study examines 33 grassland water points using vegetation field studies and remote sensing techniques to track desertification on the Mongolian *** established a significant correlation between same-year field observation(line transects)and NDVI data,enabling an historical land cover perspective to be developed from 1998 to *** show variable land cover patterns in Mongolia with a 16%decrease in plant density over the time *** in cover identified by NDVI suggests degradation;however,continued annual fluctuation indicates desertificationirreversible land cover changehas not ***,in situ data documenting greater cover near water points implies livestock overgrazing is not causing degradation at water *** combination of the two research methodsremote sensing and field surveysstrengthen findings and provide an effective way to track desertification in dryland regions.

关键词： desertification NDVI piosphere Mongolia overgrazing digital earth

Effects of water level alteration on carbon cycling in peatlands

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Ecosystem Health and Sustainability 2020年第1期6卷 199-227,198页

作者： Yehui Zhong Ming Jiang Beth A.middleton Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchunJilinPR China University of Chinese Academy of Sciences BeijingPR China Jilin Provincial Joint Key Laboratory of Changbai Mountain Wetland and Ecology ChangchunJilinPR China U.S.Geological Survey Wetlands and Aquatic Research CenterLafayetteLAUSA

Globally,peatlands play an important role in the carbon(C)*** water level is a key factor in maintaining C storage in peatlands,but water levels are vulnerable to climate change and anthropogenic *** review examines literature related to the effects of water level alteration on C cycling in peatlands to summarize new ideas and uncertainties emerging in this *** ecosystems maintain their function by altering plant community structure to adapt to changing water *** primary production,woody plants are more productive in unflooded,well-aerated conditions,while Sphagnum mosses are more productive in wetter *** responses of sedges to water level alteration are *** peat decomposition is faster in unflooded,well aerated conditions,increased plant production may counteract the C loss induced by increased ecosystem respiration(ER)for a period of *** contrast,rising water table maintains anaerobic conditions and enhances the role of the peatland as a C ***,changes in DOC flux during water level fluctuation is complicated and depends on the interactions of flooding with ***,vegetation also plays a role in C flux but particular species vary in their ability to sequester and transport *** ecosystems have a greater resilience to water level alteration than fens,due to differences in biogeochemical responses to *** full understanding of the role of peatlands in global C cycling deserves much more study due to uncertainties of vegetation feedbacks,peat-water interactions,microbial mediation of vegetation,wildfire,and functional responses after hydrologic restoration.

关键词： Peatlands carbon cycling climate change anthropogenic disturbance water level

Broken connections of wetland cultural knowledge

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Ecosystem Health and Sustainability 2016年第7期2卷 1-3页

作者： Beth A.middleton U.S.Geological Survey Wetland and Aquatic Research Center700 Cajundome BoulevardLafayetteLouisiana 70506 USA

As global agriculture intensifies,cultural knowledge of wetland utilization has eroded as natural resources become more stressed,and marginal farmers move away from the *** excellent paper by Fawzi et al.(2016)documents a particularly poignant case of traditional knowledge loss among the Marsh Arab women of *** interviews,the authors document the breakdown of skill transfer from the older to younger generation of *** authors link the loss of their cultural knowledge with the loss of wetlands in the *** can no longer provide support for their families using wetland products,and along with that,their ancient knowledge of plant usage is *** ancient skills included medicinal uses,and reed harvesting for both weaving and water buffalo ***,the majority of the Mesopotamian Marshes have dried,this way of life is being forgotten(Fawzi et al.2016).the global tragedy is that while the careful alliance of wetlands and people have sustained human cultures for millennia,degraded wetlands lose their ability to provide these services(Maltby 1986).

关键词： younger sustained wetland

the 12th International Geological Congress, toronto, 1913

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Episodes 2007年第4期30卷 290-295页

作者： Gerard V. middleton School of Geography and Earth Sciences McMaster University Hamilton ON L8S 4K1 Canada

Canada made its first bid for the 1906 IGC, but was successful seven years later. As it happened, this was a lucky chance because in the intervening years the economy had improved, due in part to the discovery of new mineral resources and the development of hydroelectric power in Ontario. the Geological Survey of Canada had been reorganized, and Provincial Departments of Mines were established in Ontario and Quebec. Research and graduate studies had developed in the three leading universities （McGill, toronto and Queen ＇s）.

关键词： 1913年全球地质学大会加拿大多伦多国际会议

the impact of alpha-fetoprotein (AFP), child-turcotte-pugh (CtP) score and disease staging on the survival of hepatocellular carcinoma (HCC) patients: a retrospective cohort from single oncology center

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Oncology research 2025年第1期33卷 149-160页

作者： Nasser Mulla Yousef Katib Asim M Almughamsi Duaa S Alkhayat Mohamed Mosaad Samir t Alfotih Rawan Alaofi Department of Internal Medicine Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Radiology Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Surgery Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Endemic and Infectious Diseases Suez Canal University Ismailia 41522 Egypt. King Salman bin Abdulaziz Medical City Madinah 42311 Saudi Arabia. Prince Mohammed Bin Abdulaziz Hospital Madinah 41511 Saudi Arabia.

Background:Hepatocellular carcinoma (HCC) is the most common cause of cancer-related death in Saudi Arabia. Our study aimed to investigate the patterns of HCC and the effect of tNM staging, Alfa-fetoprotein (AFP), and Child-turcotte Pugh (CtP) on patients' overall survival (OS).Methods:A retrospective analysis was conducted on 43 HCC patients at a single oncology center in Saudi Arabia from 2015 to 2020. All patients had to fulfill one of the following criteria: (a) a liver lesion reported as definitive HCC on dynamic imaging and/or (b) a biopsy-confirmed diagnosis.Results:the mean patient age of all HCC cases was 66.8 with a male-to-female ratio of 3.3:1. All patients were stratified into two groups: viral HCC (n = 22, 51%) and non-viral HCC (n = 21, 49%). Among viral-HCC patients, 55% were due to HBV and 45% due to HCV. Cirrhosis was diagnosed in 79% of cases. Age and sex did not significantly statistically differ in OS among viral and non-viral HCC patients (-value > 0.05). About 65% of patients had tumor size >5 cm during the diagnosis, with a significant statistical difference in OS (-value = 0.027). AFP was >400 ng/ml in 45% of the patients. there was a statistically significant difference in the OS in terms of AFP levels (-value = 0.021). A statistically significant difference was also observed between the CtP score and OS (-value = 0.02). CtP class B had the longest survival. BSC was the most common treatment provided to HCC patients followed by sorafenib therapy. there was a significant statistical difference in OS among viral and non-viral HCC patients (-value = 0.008).Conclusions:the most common predictors for OS were the underlying cause of HCC, AFP, and tumor size. Being having non-viral etiology, a tumor size >5 cm, an AFP > 400 ng/mL, and a CtP score class C were all negatively associated with OS.

关键词： Alpha-fetoprotein (AFP) Child-turcotte-pugh Hepatocellular carcinoma Pattern Progression free survival

A review of microfluidic approaches for investigating cancer extravasation during metastasis

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Microsystems & Nanoengineering 2018年第1期4卷 400-412页

作者： Yu-Heng Vivian Ma Kevin middleton Lidan You Yu Sun Institute of Biomaterials and Biomedical Engineering University of Toronto164 College StreetRoom 407TorontoON M5S 3G9Canada Department of Mechanical and Industrial Engineering University of Toronto5 King’s College RoadRoom 105TorontoON M5S 3G8Canada

Metastases,or migration of cancers,are common and severe cancer *** the 5-year survival rates of primary tumors have greatly improved,those of metastasis remain below 30%,highlighting the importance of investigating specific mechanisms and therapeutic approaches for *** devices have emerged as a powerful platform for drug target identification and drug response screening and allow incorporation of complex interactions in the metastatic microenvironment as well as manipulation of individual *** this work,we review microfluidic devices that have been developed to study cancer cell migration and extravasation in response to mechanical(section‘Microfluidic investigation of mechanical factors in cancer cell migration’),biochemical(section‘Microfluidic investigation of biochemical signals in cancer cell invasion’),and cellular(section‘Microfluidic metastasis-on-a-chip models for investigation of cancer extravasation’)*** highlight the device characteristics,discuss the discoveries enabled by these devices,and offer perspectives on future directions for microfluidic investigations of cancer metastasis,with the ultimate aim of identifying the essential factors for a‘metastasis-on-a-chip’platform to pursue more efficacious treatment approaches for cancer metastasis.

关键词： biochemical signal cancer cell migration cancer cell extravasation metastasis-on-a-chip cellular signal microfluidic mechanical signal