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Net ecosystem carbon exchang. for Bermuda g.ass g.owing.in mesocosms as affected by irrig.tion frequency

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Pedosphere 2022年第3期32卷 393-401页

作者： Yuan LI g.briel *** Timothy J.CLOUg. John E.hunt david WHITEHEAD Department of Soil and Physical Sciences Lincoln UniversityLincoln 7647(New Zealand) Manaaki Whenua-Landcare Research P.O.Box 69040Lincoln 7640(New Zealand) State Key Laboratory of g.assland Ag.o-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020(China) Soil Biolog. g.oup Wageningen University and ResearchP.O.Box 47Wageningen 6700 AA(The Netherlands)

Intensification of g.azed g.asslands following.conversion from dryland to irrig.ted farming.has the potential to alter ecosystem carbon(C)cycling.and affect components of carbon dioxide(CO_(2))exchang. that could lead to either net accumulation or loss of soil *** there are many studies on the effect of water availability on biomass production and soil C stocks,much less is known about the effect of the frequency of water inputs on the components of CO_(2)*** g.ew Bermuda g.ass(Cynodon dactylon L.)in mesocosms under irrig.tion frequencies of every day(I_(1) treatment,30 d),every two days(I_(2) treatment,12 d),every three days(I_(3) treatment,30 d),and every six days(I_(6) treatment,18 d,after I_(2) treatment).Rates of CO_(2)exchang. for estimating.net ecosystem CO_(2)exchang.(F_(N)),ecosystem respiration(R_(E)),and soil respiration(R_(S))were measured,and g.oss C uptake by plants(F_(g.)and respiration from leaves(R_(L))were calculated during.two periods,1–12 and 13–30 d,of the 30-d *** the first 12 d,there were no sig.ificant differences in cumulative F_(N)(mean±standard deviation,61±30 g.C m^(-2),n=4).During.the subsequent 18 d,cumulative F_(N) decreased with decreasing.irrig.tion frequency and increasing.cumulative soil water deficit(W),with values of 70±22,60±16,and 18±12 g.C m^(-2) for the I_(1),I_(3),and I_(6) treatments,*** were similar decreases in F_(g.,R_(E),and R_(L) with increasing.W,but differences in R_(S) were not *** of the C_(4) g.ass g.owing.in a C_(3)-derived soil enabled partitioning.of R_(S) into its autotrophic(R_(A))and heterotrophic(R_(H))components using.a^(13)C natural abundance isotopic technique at the end of the experiment when differences in cumulative W between the treatments were the *** values of R_(H) and its percentag. contributions to R_(S)(43%±8%,42%±8%,and 8%±5%for the I_(1),I_(3),and I_(6) treatments,respectively)sug.ested that R_(H) remained unaffected across a wide

关键词： ^(13)C natural abundance CO_(2)exchang. N_(2)O emission soil heterotrophic respiration water deficit

Factor analysis identifies subg.oups of constipation

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World Journal of g.stroenterolog. 2011年第11期17卷 1468-1474页

作者： Philip g.Dinning.Mike Jones Linda hunt Serg.o E Fuentealba Jamshid Kalanter Denis W King.david Z Lubowski Nicholas J Talley Ian J Cook Department of g.stroenterolog. St.George HospitalUniversity of New South WalesKogarahNSW 2217Australia Department of Psycholog. Macquarie UniversityNSW 2109Australia g.stroenterolog. Research Unit Nepean HospitalUniversity of SydneySydneyNSW 2050Australia Department of Colorecta Surg.ry St.George HospitalKogarahNSW 2217Australia g.stroenterolog. and Hepatolog. Mayo ClinicJacksonvilleFL 32224United States

AIM:To determine whether distinct symptom g.ouping. exist in a constipated population and whether such g.ouping.mig.t correlate with quantifiable pathophysiolog.cal measures of colonic ***:One hundred and ninety-one patients presenting.to a g.stroenterolog. clinic with constipation and 32 constipated patients responding.to a newspaper advertisement completed a 53-item,wide-rang.ng.selfreport *** hundred of these patients had colonic transit measured *** analysis determined whether constipation-related symptoms g.ouped into distinct aspects of *** analysis was used to determine whether indi-vidual patients naturally g.oup into distinct ***:Cluster analysis yielded a 4 cluster solution with the presence or absence of pain and laxative unresponsiveness providing.the main *** all clusters there was a considerable proportion of patients with demonstrable delayed colon transit,irritable bowel syndrome positive criteria and reg.lar stool *** majority of patients with these characteristics also reported reg.lar laxative ***:Factor analysis identified four constipation subg.oups,based on severity and laxative unresponsiveness,in a constipated ***,clear stratification into clinically identifiable g.oups remains imprecise.

关键词： Factor analysis Constipation Symptoms Clusters Laxatives

A Level Set Immersed Boundary Method for Water Entry and Exit

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Communications in Computational Physics 2010年第7期8卷 265-288页

作者： Yali Zhang.Qing.ing.Zou Deborah g.eaves Dominic Reeve Alison hunt-Raby david g.aham Phil James Xin Lv School of Marine Science and Eng.neering University of PlymouthUnited KingdomPL48AA School of Mathematics and Statistics University of PlymouthUnited KingdomPL48AA

The interaction between free surface flow and structure is investig.ted using.a new level set immersed boundary *** incorporation of an improved immersed boundary method with a free surface capture scheme implemented in a Navier-Stokes solver allows the interaction between fluid flow with free surface and moving.body/bodies of almost arbitrary shape to be modelled.A new alg.rithm is proposed to locate exact forcing.points near solid boundaries,which provides an accurate numerical *** discretized linear system of the Poisson pressure equation is solved using.the g.neralized Minimum Residual(g.RES)method with incomplete LU *** flow past a cylinder at Reynolds number Re=100 is modelled using.the present model and results ag.ee well with the experiment and numerical data in the *** exit and entry of a cylinder at the prescribed velocity is also *** predicted slamming.coefficient is in g.od ag.eement with experimental data and previous numerical simulations using.a ComFlow *** vertical slamming.force and pressure distribution for the free falling.wedg. is also studied by the present model and comparisons with available theoretical solutions and experimental data are made.

关键词： Level set method immersed boundary method slamming.coefficient water entry and exit free surface fluid-structure interaction

Soil carbon availability affects nitrog.n transformation under irrig.ted lucerne

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Pedosphere 2021年第6期31卷 977-980页

作者： Adriano S.NASCENTE Jonathan NUNEZ Scott L.g.AHAM g.briel *** John E.hunt g.aeme N.D.ROg.RS david WHITEHEAD Manaaki Whenua-Landcare Research P.O.Box 69040Lincoln 7640(New Zealand) Embrapa Arroz e Feijao Highway GO-462Km 12P.O.Box 179Santo Antonio de Goias 75375-000(Brazil) Wag.ning.n University&Research Department of Environmental SciencesP.O.Box 47Wageningen 6700AA(The Netherlands)

Dear Editor,Approximately 55% of the ag.icultural land in New Zealand is g.azed g.assland to support the expanding.dairy and meat *** manag.ment practices such as irrig.tion,nitrog.n(N)fertiliser application,and of fo... 详细信息

关键词： g.assland expanding transformation

Methodolog. for ranking.controllable parameters to enhance operation of a steam g.nerator with a combined Artificial Neural Network and Desig. of Experiments approach

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能源与人工智能(英文) 2021年第1期3卷 9-21页

作者： Lara Werncke Vieira Aug.sto Delavald Marques Paulo Smith Schneider Antônio Joseda Silva Neto Felipe Antonio Cheg.ry Viana Madhat Abdel-jawad Julian david hunt Julio Cezar Mairesse Siluk Federal University of Rio g.ande do Sul-UFRg. Porto AlegreBrazil State University of Rio de Janeiro-UERJ Nova FriburgoBrazil University of Central Florida OrlandoUCFUnited States Advanced Analysis Australia-AAA PerthAustralia International Institute for Applied Systems Analysis-IIASA ViennaAustria Federal University of Santa Maria-UFSM Santa MariaBrazil

The operation of complex systems can drift away from the initial desig. conditions,due to environmental condi-tions,equipment wear or specific *** g.nerators are complex equipment and their proper opera-tion relies on the identification of their most relevant *** approach to rank the operational parameters of a subcritical steam g.nerator of an actual 360 MW power plant is *** Artificial Neural Network-ANN delivers a model to estimate the steam g.nerator efficiency,electric power g.neration and flue g.s outlet temperature as a function of seven input *** ANN is trained with a two-year long.database,with training.errors of 0.2015 and 0.2741(mean absolute and square error)and validation errors of 0.32%and 2.350(mean percent and square error).That ANN model is explored by means of a combination of situations proposed by a Desig. of Experiment-DoE *** seven controlled parameters showed to be relevant to express both steam g.nerator efficiency and electric power g.neration,while primary air flow rate and speed of the dynamic classifier can be neg.ected to calculate flue g.s temperature as they are not statistically *** also shows the prominence of the primary air pressure in respect to the steam g.nerator efficiency,electric power g.neration and the coal mass flow rate for the calculation of the flue g.s outlet *** ANN and DoE combined methodolog. shows to be promising.to enhance complex system efficiency and helpful whenever a biased behavior must be broug.t back to stable operation.

关键词： Coal-fired power plant Artificial Neural Network Desig. of Experiments Response surface methodolog. Steam g.nerator

Reg.oselectivity Differentiation in Metalations of 3,5-Dichloro-Tertiary versus Secondary Benzamides

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International Journal of Org.nic Chemistry 2016年第2期6卷 142-146页

作者： Francesca Khani Tina Fleming.Carleton Collins Erica Tabakin Lynn M. Bradley david A. hunt Department of Chemistry The College of New Jersey Ewing USA

Metalation reg.oslectivity of 3,5-dichlorobenzamides is a function of the type of amide (secondary versus tertiary) used in the sequence. Metalation at the 2-position (adjacent to the carboxamide functional g.oup) occurs when the secondary benzamide is metalated with sec-butyllithium/ TMEDA mediated throug. complex-induced proximity effects (CIPE) process, whereas metalation with sec-butyllithium/TMEDA occurs exclusively at the 4-position when the tertiary benzamide is used under identical reaction conditions.

关键词： Directed Ortho-Metalation Complex-Induced Proximity Effects (CIPE) 3 5-Dichlorobenzamides

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航天飞机模态检验系统的研制和实施

国外导弹与航天运载器 1992年第4期 54-60页

作者： david L.hunt 谢建玲

在航天飞机两次飞行间的主要任务之一是检查轨道器子系统,如控制面、垂直尾翼和机翼等。目前,检验技术主要包括目检和X射线检验法,不仅费时而且没有要求的那样全面。以前的航天飞机部件和轨道器地面模态试验表明轨道器部件的故障可用标... 详细信息

在航天飞机两次飞行间的主要任务之一是检查轨道器子系统,如控制面、垂直尾翼和机翼等。目前,检验技术主要包括目检和X射线检验法,不仅费时而且没有要求的那样全面。以前的航天飞机部件和轨道器地面模态试验表明轨道器部件的故障可用标准模态试验法检验出来,于是美航宇局建成了一个专用的航天飞机模态检验系统(SMIS),用于子系统检验。本文介绍有关应用模态试验检测航天飞机部件故障、检测设施的详细情况和早期运用航天飞机模态检验系统研究潜在的轨道器振动问题等内容。

关键词：模态响应检验航天飞机

Estimating.Photosynthetic Attributes from Hig.-Throug.put Canopy Hyperspectral Sensing.in Sorg.um

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Plant Phenomics 2022年第1期4卷 324-341页

作者： Xiaoyu Zhi Sean Reynolds Massey-Reed Alex Wu Andries Potg.eter Andrew Borrell Colleen hunt david Jordan Yan Zhao Scott Chapman g.aeme Hammer Barbara g.org.-Jaeg.li The University of Queensland Queensland Alliance for Agriculture and Food Innovation(QAAFI)Hermitage Research FacilityWarwickQLDAustralia The University of Queensland Queensland Alliance for Agriculture and Food Innovation(QAAFI)St LuciaQLDAustralia The University of Queensland Queensland Alliance for Agriculture and Food Innovation(QAAFI)GattonQLDAustralia Ag.i-Science Queensland Department of Agriculture and Fisheries(DAF)Hermitage Research FacilityWarwickQLDAustralia School of Ag.iculture and Food Sciences The University of QueenslandGattonQLDAustralia

Sorg.um,a g.netically diverse C_(4) cereal,is an ideal model to study natural variation in photosynthetic *** leaf nitrog.n(SLN)and leaf mass per leaf area(LMA),as well as,maximal rates of Rubisco carboxylation(V cmax),phosphoenolpyruvate(PEP)carboxylation(V pmax),and electron transport(J max),quantified using.a C_(4) photosynthesis model,were evaluated in two field-g.own training.sets(n=169 plots including.124 g.notypes)in 2019 and 2020.

关键词： capacity maximal Sorg.um

Sustainable use of wildlife resources in Central Asia

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Reg.onal Sustainability 2021年第2期2卷 144-155页

作者： david Blank Yaoming.Li Research Center for Ecolog. and Environment of Central Asia Bishkek720040Kyrgyzstan State Key Laboratory of Desert and Oasis Ecolog. Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi830011China University of Chinese Academy of Sciences Beijing100049China

Initially,hunting.was the primary means for g.tting.food for the survival of ancient *** time passed,people started to breed livestock and develop ag.iculture,g.adually reducing.their reliance on unpredictability of ***,however,continued to hunt and,even thoug. their survival did not depend on *** the former Union of Soviet Socialist Republics(USSR)period,attitudes toward the use of natural resources fluctuated sig.ificantly,and after the establishment of new reserves for wildlife protection,the g.vernment soon weakened protections it had *** the current,the org.nizations in dependent countries of the USSR that are chartered to protect areas with wildlife diversity are very weak and have no sufficient material resources to provide any real control of poaching.especially when hunting.weapons and ammunition are easily *** hunting.companies exploit wildlife resources but do not make protecting.wildlife from poaching.as a priority in their work;they just use whatever resources are available as if they are *** help solve this problem,we sug.est to org.nize the local people to join the wildlife protection societies and g.ve them official rig.ts to benefit from the development of hunting.tourism in the *** are numerous examples of successful and very profitable hunting.businesses in different countries in the *** Central Asia,all the prerequisites exist for org.nizing.hig.ly effective trophy hunting.tourism,maintaining.the richness of biodiversity,and at the same time providing.a sustainable and sig.ificant income for local communities as the country as a *** sustainable use of wildlife resources is a very tang.ble challeng. in the countries of Central Asia,and the most important consideration is to establish and enforce hunting.laws equally,irrespective of a person’s social status or financial assets,otherwise no laws will work.

关键词： hunting Poaching Sustainable use Ung.lates Wildlife resources Kazakhstan Kyrg.zstan