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journal of Environmental Sciences 2021年第5期33卷 347-350页

作者： nelson j.O'Driscol Emma Vost Erin Mann Sara Klapstein Robert Tordon Matthew Lukeman Department o f Earth&Environmental Science.Acadia University WolfuilleNova ScotiaCanada B4P 2R62 Environment Canada DartmouthNova Scotia Department of Chemistry Acadia UniversityWolfuilleNova ScotiaCanada B4P 2R6

"Filtered(0.2μm)and unfiltered samples were analyzed for gross photoreduction,gross photooxidation,and net reduction rates of mercury using pseudo first-order curves.

关键词： lakes Mercury dissolved

Spread of common native and invasive grasses and ruderal trees following anthropogenic disturbances in a tropical dry forest

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Ecological Processes 2017年第1期6卷 394-407页

作者： Xavier A.jaime Skip j.Van Bloem Frank H.Koch Stacy A.C.nelson Department of Ecosystem Science and Management Texas A&M University2138 TAMUCollege StationTX 77843-2138USA Belle W.Baruch Institute of Coastal Ecology and Forest Science Clemson UniversityPO Box 596GeorgetownSC 29442USA USDA Forest Service Southern Research Station3041 East Cornwallis RoadResearch Triangle ParkNC 27709USA Center for Geospatial Analytics Department of Forestry and Environmental ResourcesNorth Carolina State UniversityRaleighNC 27695USA.

Introduction:A fundamental challenge to the integrity of tropical dry forest ecosystems is the invasion of nonnative grass *** grasses compete for resources and fuel anthropogenic *** 2012,a bulldozer from the Puerto Rico Electric Power Authority cleared a 570-m trail from a state road into a mature dry forest section of Guánica Forest to control a *** monitored colonization by a non-native invasive grass(Megathyrsus maximus),a highly invasive tree(Leucaena leucocephala),and a native grass(Uniola virgata),as well as natural regeneration,along the bulldozer *** determined whether bulldozing facilitated colonization by these species into the forest and the extent of ***:Distance from propagule source and temporal variations strongly influenced colonization by our three focal *** maximus invaded along the trail from source populations by the state *** establishment of new colonies of *** seedlings went as far as 570 m inside the forest(i.e.,at the end of the bulldozer trail),but we found most new colonies within 270 m of the *** leucocephala exhibited a similar spreading *** disturbance,Uniola virgata was distributed widely across the forest,but the highest densities were found in areas near the latter portion(>401 m)of the bulldozer ***,the species formed new clumps along more than half of the trail(250 to 570 m),apparently colonizing from undisturbed patches ***:Bulldozing facilitated the invasion of non-native *** projected community assemblage will be more fire-prone than before since *** carries fire across the landscape better than ***,emphasizing the capacity of invasive plant colonization to alter local ecological processes after only a single wildfire and bulldoze *** results provide a valuable baseline for short-term vegetation response to anthropogenic disturbances in tropical semi-deciduous dry forests.

关键词： Tropical dry forest Grass invasions Bulldozing Wildfire Leucaena leucocephala Megathyrsus(Panicum)maximus Uniola virgata

Mercury bioaccumulation in aquatic biota along a salinity gradient in the Saint john River estuary

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journal of Environmental Sciences 2018年第6期30卷 41-54页

作者： Bethany L.Reinhart Karen A.Kidd R.Allen Curry nelson j.O’Driscoll Scott A.Pavey Department of Biology and Canadian Rivers Institute University of New Brunswick Saint John Saint John New Brunswick E2L4L5 Canada Department of Biology Forestry and Environmental Management and Canadian Rivers Institute University of New Brunswick Fredericton New Brunswick E3B4A3 Canada Department of Earth and Environmental Sciences Acadia University Wolfville Nova Scotia B4P2R6 Canada Department of Biology and School of Geography & Earth Sciences McMaster University Hamilton Ontario LSS 4K1 Canada

Although estuaries are critical habitats for many aquatic species, the spatial trends of toxic methylmercury（MeHg） in biota from fresh to marine waters are poorly understood. Our objective was to determine if MeHg concentrations in biota changed along a salinity gradient in an estuary. Fourspine Stickleback（Apeltes quadracus）, invertebrates（snails,amphipods, and chironomids）, sediments, and water were collected from ten sites along the Saint john River estuary, New Brunswick, Canada in 2015 and 2016, with salinities ranging from 0.06 to 6.96. Total mercury（proxy for MeHg） was measured in whole fish and MeHg was measured in a subset of fish, pooled invertebrates, sediments, and water. Stable sulfur（δ34S）, carbon（δ13 C）, and nitrogen（δ15N） isotope values were measured to assess energy sources（S, C） and relative trophic level（N）. There were increases in biotic δ13C and δ34S from fresh to more saline sites and these measures were correlated with *** aqueous MeHg was higher at the freshwater than more saline sites, only chironomid MeHg increased significantly with salinity. In the Saint john River estuary, there was little evidence that MeHg and its associated risks increased along a salinity gradient.

关键词： Stickleback Amphipod Methylmercury Biomagnification Stable isotopes Food web

Near-infrared electroluminescence of AlGaN capped InGaN quantum dots formed by controlled growth on photoelectrochemical etched quantum dot templates

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Photonics Research 2022年第1期10卷 33-40页

作者： XIONGLIANG WEI SYED AHMED AL MUYEED HAOTIAN XUE ELIA PALMESE RENBO SONG nelson TANSU jONATHAN j.WIERER,jR. Center for Photonics and Nanoelectronics Department of Electrical and Computer EngineeringLehigh UniversityBethlehemPennsylvania 18015USA School of Electrical and Electronic Engineering The University of AdelaideAdelaideSA 5005Australia Institute for Photonics and Advanced Sensing The University of AdelaideAdelaideSA 5005Australia

Near-infrared electroluminescence of InGaN quantum dots(QDs)formed by controlled growth on photoelectrochemical(PEC)etched QD templates is *** QD template consists of PEC InGaN QDs with high density and controlled sizes,an AlGaN capping layer to protect the QDs,and a GaN barrier layer to planarize the *** transmission electron microscopy(STEM)of Stranski-Krastanov(SK)growth on the QD template shows high-In-content InGaN QDs that align vertically to the PEC QDs due to localized strain.A highAl-content A1_(0.9)Ga_(0.1)N capping layer prevents the collapse of the SK QDs due to intermixing or decomposition during higher temperature GaN growth as verified by *** of low-temperature(830℃)p-type layers is used to complete the p-n junction and further ensure QD ***,electroluminescence shows a significant wavelength shift(800 nm to 500 nm),caused by the SK QDs’tall height,high In content,and strong polarization-induced electric fields.

关键词： AlGaN polarization template

Myocardial Oxygenation Response to Stress Performing a Single-set Compared to Volume-Matched Multiple-Set of Leg Press in Untrained Young Adults

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journal of Science in Sport and Exercise 2023年第2期5卷 174-181页

作者： junhai Xu Arnold G.nelson james j.Tufano juntao Wang School of Kinesiology Louisiana State UniversityBaton RougeLouisianaUSA Faculty of Physical Education and Sport Charles UniversityPragueCzech Republic School of Sport Economic and Management Central University of Finance&EconomicsBeijingP.R.China

Background Debates exist about the preference for single-or multiple-set resistance exercise(RE)on achieving similar training outcome,however,no study examined their effects on the heart,thus,this study was to examine the effect of volume-matched single-and multiple-set RE on the myocardial response through examining rate pressure product(RPP).Methods Fourteen healthy untrained college students performed two leg press exercises(4×10 and 1×40 at 150%body mass)on different days,and each was performed twice in a counterbalanced crossover ***-and post-exercise SBP and HR were measured by auscultatory method,RPP was calculated as SBP×HR×10^(-3),RPP difference(RPPdiff)was calcu-lated by post-exercise RPP subtracting pre-exercise *** Single-set post-exercise RPP(17.48±3.16 mmHg·beats/min),HR(123.86±20.25 beats/min)was significantly greater than multiple-set post-exercise RPP(13.66±3.04 mmHg·beats/min),HR(101.61±19.14 beats/min),*** was no significant difference of SBP(141.07±9.37 vs.134.29±15.16 mmHg)between exercise protocols(P=0.13).The RPPdiff of single-set(6.74±2.86 mmHg·beats/min)was significantly greater than that of multiple-set(3.62±2.90 mmHg·beats/min)(P<0.001).Conclusions Single-set RE exerts a greater myocardial oxygenation response as compared to multiple-set,HR contributed more than SBP to the increase of RPP in *** results indicate that single-set RE can be warranted when wanting to train the heart,while multiple-set RE would appear best for those who should avoid heart stress.

关键词： Myocardial oxygen consumption Rate pressure product Heart rate Systolic blood pressure Resistance exercise

rapid strep testing in children with recently treated streptococcal pharyngitis

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Pediatric Investigation 2019年第1期3卷 27-30页

作者： Amin j.Barakat Coni Evans Monica Gill David nelson Georgetown University Medical Center Washington DCUSA Northern Virginia Pediatric Associates Falls ChurchVAUSA Children’s Medical Associates of Northern Virginia AlexandriaVAUSA

Importance:The use of the rapid antigen-detection test(RADT)has become the standard of care in the early diagnosis of group A beta-hemolytic Streptococcus(GAS)*** has been expressed over increased false positives when the child had been treated recently for GAS pharyngitis,resulting in over use of ***:To determine if the false positive rate for RADT is increased in children recently treated for GAS ***:We conducted a prospective study to evaluate 300 children from a private practice with acute pharyngitis who were treated for GAS pharyngitis within the preceding 28 days(study group)compared to 306 children of comparable age who had not been previously treated(control group).RADT and throat culture were performed on all children presenting with signs and symptoms of acute *** false positive and false negative rates were determined and compared in both ***:The false positive rate of 11.5%(23/200)in the study group was significantly higher than the false positive rate of 0 in the control *** positives were more likely to occur in younger ***:These data would indicate that while RADT is reliable in most children,it can lead to over treatment in children who have been recently treated for *** children treated in the preceding 28 days for GAS pharyngitis,the presence of infection should be determined with a throat culture *** based on a positive RADT should be reserved for children not recently treated for GAS pharyngitis.

关键词： Group A beta-hemolytic Streptococcus rapid antigen-detection test GAS pharyngitis

Indications and surgical options for small bowel, large bowel and perianal Crohn's disease

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World journal of Gastroenterology 2016年第40期22卷 8892-8904页

作者： james WT Toh Peter Stewart Matthew jFX Rickard Rupert Leong nelson Wang Christopher j Young Department of Colorectal Surgery Concord Repatriation General Hospital South Western Sydney Clinical School University of New South Wales Liverpool Hospital School of Medicine Western Sydney University Liverpool Hospital Ingham Institute of Applied Research Liverpool Hospital Discipline of Surgery Sydney Medical School the University of Sydney Department of Gastroenterology Concord Repatriation General Hospital Department of Colorectal Surgery Royal Prince Alfred Hospital

Despite advancements in medical therapy of Crohn's disease(CD), majority of patients with CD will eventually require surgical intervention, with at least a third of patients requiring multiple surgeries. It is important to understand the role and timing of surgery, with the goals of therapy to reduce the need for surgery without increasing the odds of emergency surgery and its associated morbidity, as well as to limit surgical recurrence and avoid intestinal failure. The profile of CD patients requiring surgical intervention has changed over the decades with improvements in medical therapy with immunomodulators and biological agents. The most common indication for surgery is obstruction from stricturing disease, followed by abscesses and fistulae. The risk of gastrointestinal bleeding in CD is high but the likelihood of needing surgery for bleeding is low. Most major gastrointestinal bleeding episodes resolve spontaneously, albeit the risk of re-bleeding is high. The risk of colorectal cancer associated with CD is low. While current surgical guidelines recommend a total proctocolectomy for colorectal cancer associated with CD, subtotal colectomy or segmental colectomy with endoscopic surveillance may be a reasonable option. Approximately 20%-40% of CD patients will need perianal surgery during their lifetime. This review assesses the practice parameters and guidelines in the surgical management of CD, with a focus on the indications for surgery in CD(and when not to operate), and a critical evaluation of the timing and surgical options available to improve outcomes and reduce recurrence rates.

关键词： Surgery Crohn’s disease Major abdominal surgery Perianal Inflammatory bowel disease Colon cancer

Comparative morphometric and chemical analyses of phenotypes of two invasive ambrosia beetles （Euwallacea spp.） in the United States

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Insect Science 2017年第4期24卷 647-662页

作者： Yigen Chen Paul L. Dallara Lori j. nelson Tom W. Coleman Stacy M. Hishinuma Daniel Carrillo Steven j. Seybold Department of Entomology and Nematology University of California Davis USA USDA Forest Service Pacific Southwest Research Station Davis USDA Forest Service Forest Health Protection San Bemardino California USA Tropical Research and Education Center University of Florida Homestead Florida USA

The polyphagous shot hole borer （PSHB）, Euwallacea sp., was first detected in 2003 in Los Angeles County, California, USA. Recently, this invasive species has become a major pest of many hardwood trees in urban and wildland forests throughout southern California. PSHB is nearly identical in morphology and life history to the tea shot hole borer （TSHB）, Euwallaceafornicatus, an invasive pest of hardwoods in Florida, USA and many other parts of the world. However, molecular studies have suggested that the taxa are different species. We conducted morphometric and chemical analyses of the pheno- types of Euwallacea sp. collected in southern California （Los Angeles County） and E. fornicatus collected in Florida （Miami-Dade County）. Our analyses indicated that PSHB has 3 larval instars. The third larval instar was separated from the first 2 instars by head capsule width with 0 probability of misclassification. The body length, head width, and pronotal width of PSHB adult males were significantly less than those of females. Head width and pronotal width of female PSHB were significantly less than those of female TSHB. In contrast, body length, and ratio of body length to pronotal width of female PSHB were significantly greater than those of female TSHB. However, females of these 2 species could not be separated completely by these 4 measurements because of the overlapping ranges. Cuticular hydrocarbons detected in both species were exclusively alkanes （i.e., n-alkanes, monomethylalkanes, dimethylalkanes, and trimethylalkanes）. Cuticular hydro- carbon profiles of PSHB males and females were similar, but they both differed from that of TSHB females. Cuticular hydrocarbons of PSHB were predominantly internally branched dimethylalkanes with backbones of 31 and 33 carbons, whereas cuticular hydro- carbons of TSHB females were dominated by internally branched monomethylalkanes and dimethylalkanes with backbones of 28 and 29 carbons. Multiple compounds within these classes appear

关键词： cuticular hydrocarbons Euwallaceafornicatus larval instars polyphagousshot hole borer Scolytidae tea shot hole borer

Economics and Performance of 10 Gb/s Metro Transport Over Mixed Fiber Plant of G.655 NZDF and G.652.C Zero Water-Peak Fibers

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光学学报 2003年第S1期23卷 717-718页

作者： Hans-jrg Thiele Santanu Das Raymond Boncek Lynn E. nelson OFS 791 Holmdel-Keyport Road Holmdel NJ 07733OFS 19 Schoolhouse Road Somerset NJOFS 2000 Northeast Expressway Norcross GAOFS 791 Holmdel-Keyport Road Holmdel NJ 07733

Using lower-cost lasers, 30% savings are possible for 10-Gb/s uncompensated metro transmission over NZDF, compared to G.652 fiber. We present WDM transmission results for a mixed plant of NZDF rings interconnected to ... 详细信息

关键词： of or on as Economics and Performance of 10 Gb/s Metro Transport Over Mixed Fiber Plant of G.655 NZDF and G.652.C Zero Water-Peak Fibers dBm DML EML WDM

Dissecting the molecular pathophysiology of drug-induced liver injury

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World journal of Gastroenterology 2018年第13期24卷 1373-1385页

作者： Hui Ye Leonard j nelson Manuel Gómez del Moral Eduardo Martínez-Naves Francisco javier Cubero Department of Immunology Ophtalmology and ORLComplutense University School of MedicineMadrid 28040Spain 12 de Octubre Health Research Institute(imas12) Madrid 28041Spain Institute for BioEngineering(Human Liver Tissue Engineering Faraday BuildingThe University of EdinburghThe King BuildingsMayfield RoadEdinburgh EH9 3 JLScotlandUnited Kingdom Department of Cell Biology Complutense University School of MedicineMadrid 28040Spain

Drug-induced liver injury(DILI) has become a major topic in the field of Hepatology and Gastroenterology. DILI can be clinically divided into three phenotypes: hepatocytic, cholestatic and mixed. Although the clinical manifestations of DILI are variable and the pathogenesis complicated, recent insights using improved preclinical models, have allowed a better understanding of the mechanisms that trigger liver damage. In this review, we will discuss the pathophysiological mechanisms underlying DILI. The toxicity of the drug eventually induces hepatocellular damage through multiple molecular pathways, including direct hepatic toxicity and innate and adaptive immune responses. Drugs or their metabolites, such as the common analgesic, acetaminophen, can cause direct hepatic toxicity through accumulation of reactive oxygen species and mitochondrial dysfunction. The innate and adaptive immune responses play also a very important role in the occurrence of idiosyncratic DILI. Furthermore, we examine common forms of hepatocyte death and their association with the activation of specific signaling pathways.

关键词： signaling pathways acetaminophen Drug-induced liver injury cell death reactive oxygen species