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Seasonal exports of phosphorus from intensively fertilised nested grassland catchments

Journal of Environmental Sciences 2013年第9期25卷 1847-1857页

作者： Ciaran Lewis Rashad Rafique Nelius Foley Paul Leahy Gerard morgan john Albertson Sandeep Kumar Gerard Kiely Department of Civil and Environmental Engineering University College Cork Department of Microbiology and Plant Biology University of Oklahoma Environmental Research Institute University College Cork Aquatic Services Unit Environmental Research Institute University College Cork Department of Civil and Environmental Engineering Duke University Department of Plant Science South Dakota State University

we carried out a one year （2002） study of phosphorus （P） loss from soil to water in three nested grassland catchments with known P input in chemical fertilizer and animal liquid slurry applications. Chemical fertilizer was applied to the grasslands between March and September and animal slurry was applied over the twelve months. The annual chemical P fertilizer applications for the 17 and 211 ha catchments were 16.4 and 23.7 kg P/ha respectively and the annual slurry applications were 10.7 and 14.0 kg P/ha, respectively. The annual total phosphorus （TP） export in stream-flow was 2.61, 2.48 and 1.61 kg P/ha for the 17, 211 and 1524 ha catchments, respectively, compared with a maximum permissible （by regulation） annual export of ca. 0.35 kg P/ha. The export rate （ratio of P export to P in land applications） was 9.6% and 6.6% from the 17 and 211 ha catchments, respectively. On average, 70% of stream flow and 85% of the P export occurred during the five wet months （October to February） indicating that when precipitation is much greater than evaporation, the hydrological conditions are most favourable for P export. However the soil quality and land use history may vary the results. Particulate P made up 22%, 43% and 37% of the TP export at the 17, 211 and 1524 ha catchment areas, respectively. As the chemical fertilizer was spread during the grass growth months （March to September）, it has less immediate impact on stream water quality than the slurry applications. we also show that as the catchment scale increases, the P concentrations and P export decrease, confirming dilution due to increasing rural catchment size. In the longer term, the excess P from fertilizer maintains high soil P levels, an antecedent condition favourable to P loss from soil to water. This study confirms the significant negative water quality impact of excess P applications, particularly liquid animal slurry applications in wet winter months. The findings suggest that restricted P application in w

关键词： phosphorus fertilizer slurry exports grassland land management water quality eutrophication

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Two-way communication: Volatile emission and uptake occur through the same barriers

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Molecular Plant 2023年第1期16卷 1-3页

作者： Joshua R.widhalm Meng-Ling Shih john A.morgan Natalia Dudareva Department of Horticulture and Landscape Architecture Purdue UniversityWest LafayetteIN 47907USA Center for Plant Biology Purdue UniversityWest LafayetteIN 47907USA avidson School of Chemical Engineering Purdue UniversityWest LafayetteIN 47907USA Department of Biochemistry Purdue UniversityWest LafayetteIN 47907USA

Volatile organic compounds(VOCs)are released from aboveground organs into the atmosphere and/or from roots into the soil,allowing plants to communicate and interact with their environment,including with each ***-plant communication via VOCs includes intra-and inter-species signaling as well as within-plant *** some recipient tissues,for example,VOC perception encompasses storing the modified VOC for direct defense against herbivores(Sugimoto et al.,2014)or increasing tolerance to abiotic stresses(Zhao et al.,2020).In addition,or alternatively,perceived VOCs may initiate signaling cascades that prime plant defenses(Brosset and Blande,2022).In all cases,plant VOCs are first released into the environment before being taken up and perceived by the same or neighboring *** significant progress has been made over the last several years to elucidate how VOCs are released from plant cells,these studies have also revealed new questions about how communicated VOCs are imported across cellular *** reviews(Loreto and D’Auria,2022;wang and Erb,2022)and a special issue(Vlot and Rosenkranz,2022)have proposed mechanisms for VOC perception and *** this Opinion piece,we shed light on the gaps in knowledge about VOC import and offer perspectives for future research aiming at understanding the molecular mechanisms underlying VOC-mediated communication in plants.

关键词： communicate soil barriers

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Helicobacter pylori recurrence after eradication in Latin America:Implications for gastric cancer prevention

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world Journal of Gastrointestinal Oncology 2017年第4期9卷 184-193页

作者： Juan E Corral Robertino Mera Corey w Dye Douglas R morgan Division of Gastroenterology and Hepatology Mayo Clinic Division of Gastroenterology Hepatologyand NutritionVanderbilt University Department of Medicine University of Miami Miller School of Medicine

To estimate Helicobacter pylori (H. pylori) recurrence rate in Latin America, a region with a significant H. pylori prevalence and gastric cancer burden. METHODSPubMed, LILACS, SciELO, Cochrane databases and abstracts from relevant meetings were reviewed. Information collected included: Participants’ characteristics, recruitment strategy, diagnostic modality, treatment arms, follow-up and recurrence rates. Recurrence was calculated using 100-patients-year rates, and data were pooled using a random effects model. The I2 statistic assessed between study heterogeneity. Meta-regression analyses evaluated for effect modifying variables. RESULTSLiterature search yielded 163 articles. Twelve studies involving 4848 patients from 9 countries met inclusion criteria. Four hundred and thirty-two reinfections were recorded in 5487 person-years of follow-up. Pooled analysis showed a recurrence rate of 7.9 cases per 100 person-years (95%CI: 5.3-10.5). Meta-regression revealed that neither the antibiotic schema, a second antibiotic course, nor the diagnostic modality had an impact on the observed risk of recurrence. The recurrence rate in the first year after treatment, predominantly recrudescence, was 11.2 (6.1-16.4) per 100 patient years. Recurrence in subsequent years, was only 6.2 (3.8-8.7). CONCLUSIONH. pylori recurrence rates in Latin America are significant, and with geographic variability, yet are acceptable based upon the current literature for consideration of large scale intervention trials. Further research in Latin America is warranted to evaluate the efficacy, cost-effectiveness, and potential adverse outcomes of proposed eradication programs.

关键词： Gastric cancer Reinfection Hispanic Helicobacter pylori Latin America

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Climate change effects on rangelands and rangeland management:affirming the need for monitoring

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Ecosystem Health and Sustainability 2017年第3期3卷 1-14页

作者： Daniel w.McCollum john A.Tanaka Jack A.morgan john E.Mitchell william E.Fox Kristie A.Maczko Lori Hidinger Clifford S.Duke Urs P.Kreuter Rocky Mountain Research Station USDAForest Service240 W.Prospect RoadFort CollinsColorado 80526 USA James C.Hageman Sustainable Agriculture Research and Extension Center University of WyomingDept 33541000 E.University AvenueLaramieWyoming 82071 USA USDA ARS Rangelands Resources Research Unit8408 Hildreth RoadCheyenneWyoming 82009 USA Texas A&M AgriLife Research Ecosystem Science&Management720 E.Blackland RoadTempleTexas 76502 USA Consortium for Science Policyand OutcomesArizona State UniversityPO Box 875603TempeArizona 85287 USA Ecological Society of America 1990 M StreetNWSuite 700WashingtonD.C.20036 USA Ecosystem Science and Management Texas A&M University2138 TAMUCollege StationTexas 77843 USA

Uncertainty as to the extent and magnitude of changes in conditions that might occur due to climate change poses a problem for land and resource managers as they seek to adapt to changes and mitigate effects of climate *** illustrate using scenarios of projected future conditions on rangelands in the Northern Great Plains and Desert Southwest of the United *** two regions are different in the ways climate change is projected to affect the *** of a longer and warmer growing season in the Northern Great Plains could lead to increased forage production and land *** uncertain effects on summer monsoons that primarily control rangeland productivity in the Desert Southwest,combined with the possibility of more intense and/or frequent drought events,could present land managers with challenges stemming from decreased forage production and land *** projections,though uncertain,provide land managers with basic insight into future conditions they might *** need more.A focus on vulnerability and resilience,with explicit recognition of interactions between ecological and socio-economic factors,coupled with systematic monitoring and assessment of observable conditions on the land to supplement information based on climate projections,will more effectively provide critical and specific information managers need to adaptively manage rangelands under uncertain climate futures.

关键词： adaptive management climate change indicators monitoring rangelands resilience uncertainty vulnerability

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China Scholars issue Personal Invitation to British Youth

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海外华文教育动态 2011年第12期 135-136页

作者： By john morgan

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Luminescence of Er^(3+) in Oxyfluoride Transparent Glass-Ceramics

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Journal of Rare Earths 2006年第6期24卷 699-705页

作者： Akira Ueda Steven H morgan Richard Mu Department of Physics Fisk University NashvilleTN 37208 USA

Erbium doped silicate, germanate, and tellurium-germanate oxyfluoride glasses were prepared in a bulk form. Through appropriate heat treatment of the as-prepared glasses, transparent glass-ceramics （TGCs） were obtained with the formation of β-PbF2：Er^3＋ nanocrystals in the glass matrix were confirmed by X-ray ***-defined diffraction peaks were observed in the samples after heat-treatment. The average crystal diameter of these precipitated crystals from full-width at half-maximum （FwHM） of the diffraction peak was estimated to be between 8 and 13 nm. Optical absorption, photoluminescence, and upconversion luminescence were measured on as-prepared glass and glass-ceramics. Luminescence spectra in the TGC samples revealed well-resolved, sharp stark-splitting peaks, which indicates that a majority of Er^3＋ ions has been incorporated into the crystalline phase of the nanocrystals. The intensity of the visible and near infrared luminescence mostly increases in TSG compared to that in the as-prepared glass. In 1.53 μm absorption and emission bands, the maximum absorption peak is blue-shifted from 1531 to 1507 nm, whereas the maximum emission peak is redshifted from 1535 to 1543 nm in TGC, as compared with that in glass. The bandwidth at half-maximum （BwHM） of the emission band is significantly broader in TGC than in glass, which is beneficial to the erbium-doped fiber amplifier （EDFA）. Upconversion luminescence was measured using 800 nm near-infrared light excitation. Drastically increased upconversion 1 was observed from the TGC as compared to that from their corresponding as-prepared glasses. In addition to a strong green emission centered at 545 nm because of ^4S3/2→^4I15/2 transition and a weaker red emission centered at 662 nm because of ^4F9/2→^4I15/2 transition, generally seen from the Er^3＋ doped glasses, two violet emissions centered at 410 nm because of ^2H9/2→^4I15/2 transition and centered at 379 nm because of ^4G11/2→^4I15/2 transition were also o

关键词： luminescence transparent glass-ceramics rare earths

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Interannual dynamics of stemwood nonstructural carbohydrates in temperate forest trees surrounding drought

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Journal of Forestry Research 2023年第1期34卷 77-86页

作者： Meghan J.Blumstein morgan E.Furze Department of Organismic and Evolutionary Biology Harvard University26 Oxford StCambridgeMA 02138USA Civil and Environmental Engineering Massachusetts Institute of Technology77 Massachusetts AveRoom 1-290CambridgeMA 02139USA Department of Botany and Plant Pathology Department of Forestry and Natural ResourcesPurdue University915 W State StreetWest LafayetteIN 47907USA

Interactions between water and carbon dynamics underlie drought-related tree *** whole-tree water relations have been shown to play a key role in the response to and recovery from drought,the role of nonstructural carbohydrates(NSC) and how their storage and allocation changes surrounding drought events deserves further attention and is critical for understanding tree ***,we quantified in situ NSC responses of temperate forest trees to the 2016 drought in the northeastern United *** and starch concentrations were measured in the stemwood of five tree species from 2014 to 2019,which allowed us to monitor NSCs in relation to climatic conditions before,during,and after the natural *** found that immediately following the drought,measured stemwood NSC concentrations ***,NSC concentrations rebounded quickly within three ***,trees allocated proportionally more to starch than to sugars following the 2016 *** winter 2017,starch comprised 45% of total stemwood stores,whereas starch made up only 1-2% in other ***,we modeled and assessed the climatic drivers of total NSC concentrations in the *** in total NSC concentrations was significantly predicted by the previous year’s temperature,precipitation,and standardized precipitation-evapotranspiration index(SPEI),with stemwood concentrations decreasing following hotter,drier periods and increasing following cooler,wetter ***,our work provides insight into the climatic drivers of NSC storage and highlights the important role that a tree’s carbon economy may play in its response and recovery to environmental stress.

关键词： Drought Nonstructural carbohydrates Starch metabolism Forest trees

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低能氦等离子体低温条件下钨材料的表面形貌

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原子能科学技术 2016年第11期50卷 2027-2033页

作者：贾玉振刘伟 T.w.morgan 清华大学材料学院北京100084 荷兰基础能源研究所

为研究氦等离子体在钨表面造成的表面纳米结构,利用荷兰基础能源研究所Pilot-PSI直线等离子体发生装置在673K温度下,对钨材料进行了低能(40eV)高束流强度(4×1023 m-2·s-1)氦等离子体辐照。实验结果表明,辐照后钨材料表面出现了多种不... 详细信息

为研究氦等离子体在钨表面造成的表面纳米结构,利用荷兰基础能源研究所Pilot-PSI直线等离子体发生装置在673K温度下,对钨材料进行了低能(40eV)高束流强度(4×1023 m-2·s-1)氦等离子体辐照。实验结果表明,辐照后钨材料表面出现了多种不同形态的纳米结构,表面纳米结构和晶粒的表面法向之间存在明显关联。在表面法向为[111]的晶粒表面出现三角形的纳米结构,在[110]取向的晶粒表面出现条带状的纳米结构,而在[001]取向的晶粒表面没有明显的结构出现。晶粒表面的纳米结构尺寸在50nm左右,高度起伏在5nm以下。另外,氦等离子体辐照会造成晶界处的高度差,在25nm左右。分析推测氦等离子体辐照造成的晶粒表面和晶界的形貌可能是由近表面的气泡所导致的。

关键词：氦等离子体钨表面形貌晶体取向

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Protease supplementation reduced the heat increment of feed and improved energy and nitrogen partitioning in broilers fed maize-based diets with supplemental phytase and xylanase

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Animal Nutrition 2022年第3期10卷 19-25页

作者： Klint w.McCafferty Mingan Choct Sosthene Musigwa Natalie K.morgan Aaron J.Cowieson Amy F.Moss USDA-ARS Poultry Research Unit School of Environmental and Rural SciencesMississippi State39762United States University of New England ArmidaleNSW2351Australia DSM Nutritional Products Kaiseraugst4303Switzerland

An experiment was conducted to explore the effects of digestible amino acid(dAA)concentrations and supplemental protease on live performance and energy partitioning in *** 308 male broilers(n?288)were distributed into 24 floor pens and offered 1 of 4 dietary treatments with 6 replicates from 1 to 35 d of *** treatments consisted of a 2×2 factorial arrangement with dAA concentrations(standard and reduced[34 g/kg below standard])and supplemental protease(without or with)as the main *** 1,15,28,and 35 d of age,feed and broilerswereweighed to determine live ***20 to 23 d of age,a total of 32 birds(2 birds/chamber,4 replicates)were placed in closed-calorimeter chambers to determine respiratory exchange(heat production,HP),apparent metabolisable energy(AME),retained energy(RE),and net energy(NE).From 29 to 35 d of age,supplemental protease in the reduced-dAA diet decreased broiler feed conversion ratio(FCR)by 5.6 points,whereas protease supplementation in the standard-dAA diet increased FCR by 5.8 *** indirect calorimetry assay revealed that supplemental protease decreased(Pwith supplemental protease had a higher daily body weight gain(BwG)(t10.4%),N intake(t7.1%),and N retention(t8.2%)than those offered the standard-dAA with supplemental *** offered the reduced-dAA without supplemental protease exhibited a 3.6%higher AME-to-crude protein(CP)ratio than those offered other *** supplementation in the standard-and reduced-dAA diets resulted in 2.7%and 5.6%lower AME intake-to-N retention ratios,respectively,compared with the unsupplemented ***-dAA increased(P<0.05)AME intake(t4.8%),RE(t9.8%),NE intake(t5.8%),NE intake-to-CP ratio(t3.0%),and RE fat-to-RE ratio(t8.6%).Protease supplementation increased(P<0.05)respiratory quotient(t1.2%)and N retention-to-N intake ratio(t2.2%),

关键词： Exogenous enzyme Mono-component protease Net energy Amino acid

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Extreme hyperbilirubinemia: An indicator of morbidity and mortality in sickle cell disease

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world Journal of Hepatology 2019年第3期11卷 287-293页

作者： john Paul Haydek Cesar Taborda Rushikesh Shah Preeti A Reshamwala morgan L McLemore Fuad El Rassi Saurabh Chawla Department of Medicine Emory University School of Medicine Division of Digestive Diseases Department of Medicine Emory University School of Medicine Department of Hematology and Medical Oncology Emory University School of Medicine

BACKGROUND Sickle cell disease(SCD) is a disorder that results in increased hospitalizations and higher mortality. Advances in management have resulted in increases in life expectancy and led to increasing awareness of sickle cell hepatopathy(SCH).However, its impact in patients on the natural history and outcomes of SCD is not known. Our study aims to describe the prevalence of extreme hyperbilirubinemia(EH), one form of SCH, its effect on morbidity and mortality,and correlations between sickle cell genotype and SCH type. we hypothesize that EH is associated with higher morbidity and *** To investigate the effects of EH on morbidity and mortality among patients with *** This retrospective cohort study was performed using a database of patients with SCD treated at Grady Memorial Hospital between May 2004 and January *** with EH(defined as total bilirubin above 13.0 mg/dL) were identified. A control group was identified from the same database with patients with total serum bilirubin ≤ 5.0 mg/dL. Electronic medical records were used to extract demographic information, laboratory values, radiology results, current medications, need for transfusions and mortality data. Two samples T-test, chi-squared test and Fisher's exact test were then used to compare the parameters between the two *** Out of the database, fifty-seven charts were found of patients with bilirubin > 13 mg/dL. Prevalence of severe SCH as defined by EH was 4.8%(57/1172). There were no demographic differences between patients with and without *** genotypic differences existed between the two groups, with hemoglobin SS SCD being much higher in the EH group(P with severe EH had a significant elevations in alanine aminotransferase(157.0 ± 266.2 IU/L vs 19.8 ± 21.3 IU/L, P < 0.001), aspartate aminotransferase(256.5 ± 485.9 U/L vs 28.2 ± 14.7 U/L, P < 0.001) and alkaline phosphatase(218.0 ± 176.2 IU/L vs 85.9 ± 68.4 IU/L, P < 0.001). Patients

关键词： Sickle cell disease Sickle cell hepatopathy Liver diseases Extreme hyperbilirubinemia Mortality

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