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j.urnal of Geoscience and Environment Protection 2021年第12期9卷 244-264页

作者： Wali Elekwachi Philip O. Phil-Eze Etiese A. Etuk collins H. Wizor Chinedu j. Onyishi Department of Geography University of Nigeria University Road Nsukka Enugu State Nigeria Clean Nigeria Associates Limited/Gte Arcon Shed 1 Nigeria Ports Authority Port Harcourt Rivers State Nigeria Department of Geography and Environmental Management University of Port-Harcourt Choba Port-Harcourt Nigeria

Wetlands are classified as essential and valuable components of the ecosystem. Wetlands are significant for ecosystem services such as nutrient cycles, soil formation and water treatment. Nearly half of the world’s wetlands have vanished in the last century because of anthropogenic activities, agricultural land use, and urban development, one of such places that are faced with the challenges of sustainability is the wetland habitats. This study aimed at assessing the spatial temporal characteristics of wetlands ecosystem in the Niger Delta Region of Nigeria from 1986-2016. The secondary data include raw satellite imageries obtained from the archive of the United States Geological Survey and Earth Explorer. The data set includes a notable period of four years landsat images for, 1986, 1996, 2006 and 2016. The maps were proj.cted using Universal Transverse Mercator (UTM) proj.ction system and datum WGS 84 of zone 32. Satellite images of the study area were acquired from the United States Geological Survey (USGS). The USGS uses the LandSat5 Thematic Mapper (TM) Landsat7 Thematic Mapper, Enhanced Thematic Mapper (ETM+), Thermal Infrared Sensor (TIRS) and Landsa8 Operational Land Imager (OLI) to generate high resolution images that are useful for this type of study. The satellite imageries were also analyzed using GIS and Remote Sensing techniques by computing of Normalized Differential Vegetation Index (NDVI) values for the entire study area by conversion of spectral reflectance values into NDVI values. The satellite images covering the area were acquired and analyzed using ArcGIS10.6. A total area of 25,053.93 (km2) was delineated in the study area. After processing the imagery, five land use/land cover (LULC) classes were developed in ArcGIS environment, such as Built-up area, Fallow land, Vegetation, Wetland and Waterbody.

关键词： Wetland Ecosystem Land Cover Multiple Linear Regression Analysis GIS Remote Sensing

Artificial intelligence and remote sensing for spatial prediction of daily air temperature:case study of Souss watershed of Morocco

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Geo-Spatial Information Science 2022年第2期25卷 244-258页

作者： Modeste Meliho Abdellatif Khattabi Driss Zej.i collins Ashianga Orlando Caleb E.Dansou Ecole Nationale des Sciences Appliquées Kénitra-Laboratoire Ingénierie des Systèmes Avancés(ISA) UniversitéIbn TofailKenitraMorocco Ecole Nationale Forestière d’Ingénieurs SaléMorocco Ecole Nationale des Sciences Appliquées Kénitra-Laboratoire Ingénierie des Systèmes Avancés(ISA) SaléMorocco Sciences de données École des sciences de l’information(ESI)RabatMorocco

Air temperature(Tair)is a fundamental variable in climate research and climate impact *** field observations do not accurately capture its spatial distribution due to the sparse and uneven distribution of weather stations,especially in remote areas where the local variability is *** circumvent this problem,in this study,remote sensing and weather station data were used to estimate Tair in the Souss watershed in *** statistical methods,including linear regression and partial least squares(PLS),and four machine learning algorithms,namely k-nearest neighbors,random forest(RF),extreme gradient boost,and Cubist,were used for modeling and predicting Tair and its performance were evaluated using random subsets and *** resolution imaging spectroradiometer predictors,including Terra band 32 emissivity,Terra nighttime land surface temperature,Terra local time of night observation,Aqua band 31 emissivity,Aqua daytime land surface tempera-ture,and Aqua nighttime land surface temperature(ALSTN),and auxiliary inputs,including sky-view,elevation,slope,and hillshade,were used as inputs for *** results showed that the Cubist and RF were the most accurate models(RMSE=2.09°C and 2.13°C,R2=0.91 and 0.90,respectively),while PLS had the lowest predictive power(RMSE=2.71°C;R2=0.83).The overall performance of the models for estimating Tair in the study area was generally satisfac-tory,with RMSE limited to less than 3°C for all ***,the station data reliability was still an issue,with only four of the seven stations marked by complete meteorological data.

关键词： Air temperature remote sensing machine learning Morocco

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冠状动脉外科的现状

国外医学.心血管疾病分册 1979年第1期 70-71页

作者： j.hn j. collins j. 麻省波士顿彼得本伯利根医院胸外科主任

我所讲的题目是冠状动脉疾病的外科,而不是心绞痛的治疗,对冠状动脉阻塞性疾病手术治疗的争论,很大一部份是由于把心绞痛作为一种疾病。心绞痛不是一种疾病,仅是疾病的一种症状,实际上约20％心绞痛病人无显著冠状动脉阻塞性疾病。在心... 详细信息

我所讲的题目是冠状动脉疾病的外科,而不是心绞痛的治疗,对冠状动脉阻塞性疾病手术治疗的争论,很大一部份是由于把心绞痛作为一种疾病。心绞痛不是一种疾病,仅是疾病的一种症状,实际上约20％心绞痛病人无显著冠状动脉阻塞性疾病。在心绞痛而无冠状动脉阻塞的病人,其预期寿命正常。Cleveland医院的材料显示,单支血管病变的五年生存率为83.4％,二支血管病变为62.6％,三支血管病变为46.2％,但也有人

关键词：冠状动脉病人手术后心绞痛冠心病外科血管病变

Distribution,structure and biosynthetic gene families of(1,3;1,4)-β-glucan in Sorghum bicolor

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j.urnal of Integrative Plant Biology 2015年第4期57卷 429-445页

作者： Riksfardini A.Ermawar Helen M.collins Caitlin S.Byrt Natalie S.Betts Marilyn Henderson Neil j.Shirley j.lian Schwerdt j.lle Lahnstein Geoffrey B.Fincher Rachel A.Burton Australian Research Council Centre of Excellence in Plant Cell Walls University of Adelaide

In cereals, the presence of soluble polysaccharides including（1,3;1,4）-b-glucan has downstream implications for human health, animal feed and biofuel applications. Sorghum bicolor（L.） Moench is a versatile crop, but there are limited reports regarding the content of such soluble ***, the amount of（1,3;1,4）-b-glucan present in sorghum tissues was measured using a Megazyme assay. Very low amounts were present in the grain, ranging from 0.16%–0.27%（w/w）, while there was a greater quantity in vegetative tissues at 0.12–1.71%（w/w）. The fine structure of（1,3;1,4）-b-glucan, as denoted by the ratio of cellotriosyl and cellotetraosyl residues,was assessed by high performance liquid chromatography（HPLC） and ranged from 2.6–3：1 in the grain, while ratios in vegetative tissues were lower at 2.1–2.6：1. The distribution of（1,3;1,4）-b-glucan was examined using a specific antibody and observed with fl uorescence and transmission electron microscopy. Micrographs showed a variable distribution of（1,3;1,4）-b-glucan in fl uenced by temporal and spatial factors. The sorghum orthologs of genes implicated in the synthesis of（1,3;1,4）-b-glucan in other cereals, such as the Cellulose synthase-like（Csl） F and H gene families were de *** pro filing of these genes across sorghum tissues was carried out using real-time quantitative polymerase chain reaction, indicating that, as in other cereals, Csl F6 transcripts dominated.

关键词： Cellulose synthase-like genes cell wall composition mixed-linkage glucan grain sorghum

Relationship between nitrate headache and outcome in patients with acute stroke: results from the efficacy of nitric oxide in stroke (ENOS) trial

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Stroke & Vascular Neurology 2021年第2期6卷 180-186页

作者： Lucy Beishon Lisa j.Woodhouse Daniel Bereczki Hanne K Christensen Ronan collins j.hn Gommans Christina Kruuse George Ntaios Serefnur Ozturk Stephen Phillips Stuart Pocock Szabolcs Szatmari j.anna Wardlaw Nikola Sprigg Philip M Bath Stroke Trials Unit Division of Clinical NeuroscienceUniversity of NottinghamNottinghamUK Department of Neurology Semmelweis UniversityBudapestHungary Bispebj.rg Hospital and University of Copenhagen University of CopenhagenCopenhagenDenmark Department of Geriatric and Stroke Medicine Adelaide and Meath HospitalDublinIreland Department of Medicine Hawke's Bay HospitalCamberleyNew Zealand Department of Neurology Herlev Gentofte HospitalUniversity of CopenhagenCopenhagenDenmark Department of Medicine Larissa University HospitalUniversity of ThessalyVolosGreece Department of Neurology Selcuk University Medical FacultyKonyaTurkey Department of Neurology Queen Elizabeth II Health Sciences CentreHalifaxNova ScotiaCanada Medical Statistics Unit London School of Hygiene&Tropical MedicineLondonUK Department of Neurology George Emil Palade University of MedicinePharmacyScience and Technology of Târgu MureșTargu MuresRomania Centre for Clinical Brain Sciences University of EdinburghEdinburghUK Stroke Nottingham University Hospitals NHS TrustNottinghamUK

Introduction Nitrate-induced headache is common and may signify responsive cerebral *** assessed the relationship between nitrate headache and outcome in patients with acute *** and methods Patients were those randomised to glyceryl trinitrate(GTN)versus no GTN in the efficacy of nitric oxide in stroke *** of headache by end of treatment(day 7),and functional outcome(modified Rankin Scale,primary outcome)at day 90,were *** are adj.sted for baseline prognostic factors and give OR and mean difference(MD)with 95%*** In 4011 patients,headache was more common in GTN than control(360,18.0% vs 170,8.5%;p<0.001).Nitrate-related headache was associated with:younger age,female sex,higher diastolic blood pressure,non-total anterior circulation syndrome,milder stroke and absence of dysphasia(p<0.05).Nitrate headache was not associated with improved functional outcome(OR 0.90,95% CI 0.73 to 1.10,p=0.30)or death(day 90)(HR 0.64,95% CI 0.40 to 1.02,p=0.062),but reduced death or deterioration(day 7)(OR 0.45,95% CI 0.25 to 0.82),death in hospital(OR 0.44,95% CI 0.22 to 0.88)and improved activities of daily living(Barthel index,MD 3.7,95% CI 0.3 to 7.1)and cognition(telephone interview cognitive screen,MD 2.0,95% CI 0.7 to 3.3)(day 90).Non-nitrate headache was not associated with death,disability or *** and conclusion Development of a nitrate headache by day 7 after stroke may be associated with improved activities of daily living and cognitive impairment at day 90,which was not seen with non-nitrate headache.

关键词： headache patients nitrate

Environment-dependent attack rates of cryptic and aposematic butterflies

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Current Zoology 2018年第5期64卷 663-669页

作者： Brett M. SEYMOURE Andrew RAYMUNDO Kevin j. MCGRAW W. OWEN MCMILLAN Ronald L, RUTOWSKI Department of Biology Colorado State University Fort Collins CO 80523 USA School of Life Sciences Arizona State University Tempe AZ 85287 USA Smithsonian Tropical Research Institute Panama City Panama

Many organisms have evolved adaptive coloration that reduces their risk of predation. Cryptic colo- ration reduces the likelihood of detection/recognition by potential predators, while warning or aposematic coloration advertises unprofitability and thereby reduces the likelihood of attack. Although some studies show that aposematic coloration functions better at decreasing attack rate than crypsis, recent work has suggested and demonstrated that crypsis and aposematism are both successful strategies for avoiding predation. Furthermore, the visual environment （e.g., ambient lighting, background） affects the ability for predators to detect prey. We investigated these 2 related hypoth- eses using 2 well-known visually aposematic species of Heliconius butterflies, which occupy differ- ent habitats （open-canopy vs. closed-canopy）, and one palatable, cryptic, generalist species j.nonia coenia. We tested if the differently colored butterflies differ in attack rates by placing plasti- cine models of each of the 3 species in 2 different tropical habitats where the butterflies naturally occur： disturbed, open-canopy habitat and forested, closed-canopy habitat. The cryptic model had fewer attacks than one of the aposematic models. Predation rates differed between the 2 habitats, with the open habitat having much higher predation. However, we did not find an interaction between species and habitat type, which is perplexing due to the different aposematic phenotypes naturally occurring in different habitats. Our findings suggest that during the Panamanian dry sea- son avian predation on perched butterflies is not a leading cause in habitat segregation between the 2 aposematic species and demonstrate that cryptically colored animals at rest may be better than aposematic prey at avoiding avian attacks in certain environments.

关键词： avian attacks camouflage Heliconius j.nonia light environment plasticine models predation warning coloration.

Effect of calcination temperature on steam reforming activity of Ni-based pyrochlore catalysts

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j.urnal of Rare Earths 2020年第7期38卷 711-718,I0002页

作者： Daniel j.Haynes Dushyant Shekhawat David Berry Amitava Roy j.mes j.Spivey National Energy Technology Laboratory U.S.Department of Energy3610 Collins Ferry RdMorgantownWV26507 USA Louisiana State University Cain Department of Chemical Engineering3307 Patrick Taylor HallBaton RougeLA70803USA

This work served as the second part of a study evaluating the effect of calcination temperature(700-1000℃) on Ni-based lanthanum zirconate pyrochlore catalysts for methane steam reforming.A previous study(Haynes et ***.2017(43) 16744) provided a thorough characterization of the material properties for the catalysts used here,and this study focuses on the evaluation of catalytic *** activity was assessed by two different experimental studies:the effect of reaction temperature using a temperature programmed surface reaction(TPSR),and the effect of reaction *** results demonstrate a complex interaction between the Ni particles and surface LaOx species under the methane steam reforming ***,the material calcined at the lowest temperature(700℃) possesses the highest activity and selectivity,which is attributed to smaller and more welldispersed Ni particles on the surface,and,more importantly,a lesser degree La enrichment at the *** catalysts were deactivated by steam to NiO under all conditions tested,but at certain low reaction pressure(p=0.23 MPa) conditions the materials calcined at 700-900℃ are able to completely recover equilibrium activity in-situ that is then robust and stable under both low and high reaction pressures(p=1.8 MPa) suggesting the formation of a synergistic relationship between Ni and La for syngas ***,exposure of a fresh material to high reaction pressures leads to a rapid and irreversible loss in both CH4 conversion and syngas selectivity whether in the fresh(no pretreatment),or pretreated(steam,H2 or Ar only at 800℃) form for any *** mechanism for deactivation appears to be due to the presence of LaOx species that become mobile,possibly by the formation of La-OH,and covers the active Ni particles and inhibits sites responsible for the CH4 decomposition.

关键词： Nickel Pyrochlore Methane Steam reforming Catalyst Lanthanum enrichment

Massive energy storage systems enable secure electricity supply from renewables

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j.urnal of Modern Power Systems and Clean Energy 2016年第4期4卷 659-667页

作者： Alan j.SANGSTER School of Engineering and Physical Sciences Heriot-Watt UniversityRiccarton CampusEdinburgh EH144ASUK

Climate change is mainly attributed to the burning of fossil *** solve the problem,current inhabitants have to dispense with fossil fuels as a source of *** has been demonstrated that this can be secured before 2050 by transitioning to renewable sources of *** energy storage(mes)incorporated into long distance high voltage direct current(HVDC)transmission systems is the key technology for the *** paper describes the current state-of-the-art in electricity grid *** demonstrates how mes,and other back-up local electricity storage schemes represent a natural way of buffering electricity consumers from the intermittency of inherent in the primary renewable ***,it can solve the base-load issues and facilitate a global transition to 100%renewable energy sources over the next fifteen to twenty years.

关键词： Electricity grid Energy storage Pumpedhydro Lagoon storage Hydraulic piston Climate change

Rock characterization while drilling and application of roof bolter drilling data for evaluation of ground conditions

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j.urnal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 273-281页

作者： j.mal Rostami Sair Kahraman Ali Naeimipour Craig collins Department of Energy and Mineral Engineering Pennsylvania State University Mining Engineering Department Hacettepe University j.H. Fletcher & Co.

Despite recent advances in mine health and safety, roof collapse and instabilities are still the leading causes of inj.ry and fatality in underground mining operations. Improving safety and optimum design of ground support requires good and reliable ground characterization. While many geophysical methods have been developed for ground characterizations, their accuracy is insufficient for customized ground support design of underground workings. The actual measurements on the samples of the roof and wall strata from the exploration boring are reliable but the related holes are far apart, thus unsuitable for design purposes. The best source of information could be the geological back mapping of the roof and walls, but this is disruptive to mining operations, and provided information is only from rock *** of the data obtained from roof bolt drilling can offer a good and reliable source of information that can be used for ground characterization and ground support design and evaluations. This paper offers a brief review of the mine roof characterization methods, followed by introduction and discussion of the roof characterization methods by instrumented roof bolters. A brief overview of the results of the preliminary study and initial testing on an instrumented drill and summary of the suggested improvements are also discussed.

关键词： Roof bolter Rock characterization Three-dimensional(3D) visualization of ground Ground support optimization