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Global and Regional Surface Nitrogen Balances in Intensive Agricultural production Systems for the period 1970-2030

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pedosphere 2005年第2期15卷 137-155页

作者： A. F. BOUWMAN G.Van DRECHT k. W. Van der HOEk Netherlands Environmental Assessment Agency Netherlands Environmental Assessment AgencyLaboratory for Environmental Monitoring National Institute for Public Health and the EnvironmentP .O. Box 13720 BA Bilthoven (The Netherlands)National Institute for Public Health and the EnvironmentP .O. Box 13720 BA Bilthoven (The Netherlands)National Institute for Public Health and the EnvironmentP. O. Box 13720 BA Bilthoven (The Netherlands)

Global nitrogen (N) budgets for intensive agricultural systems were compiled for a 0.5 by 0.5 degree resolution. These budgets include N inputs (N fertilizer, animal manure, biological N fixation and atmospheric N deposition) and outputs (N removal from the field in harvested crops and grass and grass consumption by grazing animals, ammonia volatilization,denitrification and leaching). Data for the historical years 1970 and 1995 and a projection for 2030 were used to study changes in the recovery of N and the different loss terms for intensive agricultural systems. The results indicate that the overall system N recovery and fertilizer use efficiency slowly increased in the industrialized countries between 1970 and 1995, the values for developing countries have decreased in the same period. For the coming three decades our results indicate a rapid increase in both the industrialized and developing countries. High values of ＞ 80% for fertilizer use efficiency may be related to surface N balance deficits, implying a depletion of soil N and loss of soil fertility. The projected intensification in most developing countries will cause a gradual shift from deficits to surpluses in the coming *** projected fast growth of crop and livestock production, and intensification and associated increase in fertilizer inputs will cause a major increase in the surface N balance surplus in the coming three decades. This implies increasing losses of N compounds to air (ammonia, nitrous oxide and nitric oxide), and groundwater and surface water (nitrate).

关键词： animal manure fertilizer intensive agriculture nitrogen surface balance

Hyperactive learning for data-driven interatomic potentials

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npj Computational Materials 2023年第1期9卷 599-612页

作者： Cas van der Oord Matthias Sachs Dávid péter kovács Christoph Ortner Gábor Csányi University of Cambridge Cambridge CB21PZUK University of Birmingham Birmingham B152TTUK University of British Columbia VancouverBC V6T 1Z2Canada

Data-driven interatomic potentials have emerged as a powerful tool for approximating ab initio potential energy *** most time-consuming step in creating these interatomic potentials is typically the generation of a suitable training *** aid this process hyperactive learning(HAL),an accelerated active learning scheme,is presented as a method for rapid automated training database *** adds a biasing term to a physically motivated sampler(*** dynamics)driving atomic structures towards uncertainty in turn generating unseen or valuable training *** proposed HAL framework is used to develop atomic cluster expansion(ACE)interatomic potentials for the AlSi10 alloy and polyethylene glycol(pEG)polymer starting from roughly a dozen initial *** HAL generated ACE potentials are shown to be able to determine macroscopic properties,such as melting temperature and density,with close to experimental accuracy.

关键词： starting generating consuming

Ion Beam Extracted from a 14GHz ECRIS of CApRICE Type

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Chinese physics C 2007年第S1期31卷 192-195页

作者： p.Spdtke I J.Mder J.Roβbach k.Tinschert J.Stetson GSI DarmstadtGermany MSU-NSCL MichiganUSA

An ion beam extracted from an ECRIS suffers from the inhomogeneous distribution of cold electrons within the minimum B configuration,necessary to confine the *** for higher ion currents,the space charge force is not negligible any more,and because of the nonlinear force,emittance growth will occur. Measurements of the profile and the emittance of the beam directly behind the source show the complicated correlation between extraction voltage and plasma *** emittance has been measured with a pepper pot device to account for the inhomogeneous azimuthal distribution of the *** results indicate that further information about the profile is *** visualize the beam profile a tantalum foil with a thickness of 20μm has been used for an electrical beam power between 10 and *** on the back side of the foil with a CCD camera it is possible to record the profile in real *** a more sensitive diagnostic tool viewing targets made from BaF has been used. Three dimensional computer simulations have been used to identify the reason for the structures,observed in measurements.

关键词： ECRIS extraction extraction simulation beam profile

Expansion of traditional land-use and deforestation:a case study of an adat forest in the kandilo Subwatershed,East kalimantan,Indonesia

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Journal of Forestry Research 2018年第2期29卷 488-506页

作者： Hunggul Y.S.H.Nugroho Anne van der Veen Andrew k.Skidmore Yousif A.Hussin Department of pGM Faculty of Geo-Information Science and Earth ObservationUniversity of TwenteP.O.Box 2177500 AE EnschedeThe Netherlands Environment and Forestry Research and Development Institute of Macassar(Bp2LHk Makassar) Jl.Perintis Kemerdekaan Km.165 SudiangMakassarSulawesi SelatanIndonesia Department of Natural Resources Faculty of Geo-Information Science and Earth ObservationUniversity of TwenteP.O.Box 2177500 AE EnschedeThe Netherlands

Deforestation issues are more problematic when indigenous(adat) communities,living within a forest,have lived there for many *** adat communities,who employ traditional land-use,are frequently accused of encroaching on the *** understand existing and future trends in the spatial patterns of the expansion of traditional land-use and deforestation,we conducted a case study in the kandilo Subwatershed using mixed methods with image interpretation,spatial modelling and sociocultural surveys to examine the interrelationships between physical conditions,community characteristics and traditional land-use *** investigated community characteristics through household interviews,communication with key informants,and discussions with *** using an area production model,we were able to analyze the effect of improved farming systems,policy intervention and law enforcement on traditional land-use expansion and *** on our examination of a 20-year period of traditional land-use activities in adat forests,the evidence indicated that the steeper the slope of the land and the farther the distance from the village,the lower the rate of *** study found that customary law,regulating traditional land-use,played an important role in controlling deforestation and land *** conclude that the integration of land allocation,improved farming practices and enforcement of customary law are effective measures to improve traditional land productivity while avoiding deforestation and land degradation.

关键词： Adat people Agriculture expansion Area production model(ApM) Customary law Deforestation Traditional land-use

The influence of mobility among high-risk populations on HIV transmission in Western kenya

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Infectious Disease Modelling 2018年第1期3卷 97-106页

作者： Anna Bershteyn kennedy k.Mutai Adam N.Akullian Daniel J.klein Britta L.jewell Samuel M.Mwalili Institute for Disease Modeling 3150139th Ave.SEBellevueWA 98005USA National Aids Control Council P.O.Box 61307-00200Argwings Kodhek RdNairobiKenya Department of Medicine University of California and San FranciscoZuckerberg San Francisco General Hospital1001 Potrero AvenueSan FranciscoCA 94110USA Centers for Disease Control and prevention PO Box 606Village MarketNairobi00621Kenya

Western kenya suffers a highly endemic and also very heterogeneous epidemic of human immunodeficiency virus(HIV).Although female sex workers(FSW)and their male clients are known to be at high risk for HIV,HIV prevalence across regions inWestern kenya is not strongly correlated with the fraction of women engaged in commercial *** agentbased network model of HIV transmission,geographically stratified at the county level,was fit to the HIV epidemic,scale-up of interventions,and populations of FSW in Western kenya under two assumptions about the potential mobility of FSW *** the first,all clients were assumed to be resident in the same geographies as their interactions with *** the second,some clients were considered non-resident and engaged only in interactions with FSW,but not in longer-term non-FSW partnerships in these *** both assumptions,the model successfully reconciled disparate geographic patterns of FSW and HIV *** patterns in the model suggest a greater role for FSW in local transmission when clients were resident to the counties,with 30.0%of local HIV transmissions attributable to current and former FSW and clients,compared to 21.9%when mobility of clients was ***,the overall epidemic drivers remained similar,with risky behavior in the general population dominating transmission in highprevalence *** modeling suggests that co-location of high-risk populations and generalized epidemics can further amplify the spread of HIV,but that large numbers of formal FSW and clients are not required to observe or mechanistically explain high HIV prevalence in the general population.

关键词： prevalence client stratified

Effect of impinging angle and rotating speed on erosion behavior of aluminum

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Transactions of Nonferrous Metals Society of China 2011年第1期21卷 32-38页

作者： A.k.JHA R.BATHAM M.AHMED A.k.MAJUM der O.p.MODI S.CHATURVEDI A.k.GUpTA Advanced Materials and processes Res earch Institute

Commercial aluminum（grade 1900） in rotary motion was exposed to slurry of sand in *** were mounted at various angles and rotated at different *** rate was calculated using mass loss *** results show that wear rates increase with increasing impingement angle up to 90°.Contrary to the conventional understanding of maximum loss of ductile material at about 45° impingement angle,maximum wear rate was observed in case of the aluminum sample fixed at 90°.However,increasing rotation speed of the samples results in exponential increase in wear *** findings are substantiated with the metallographic study of worn surface.

关键词： aluminum slurry erosion impinging wear

Effects of undigested protein-rich ingredients on polarised small intestinal organoid monolayers

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Journal of Animal Science and Biotechnology 2020年第4期11卷 1026-1032页

作者： Soumya k.kar Bart van der Hee Linda M.p.Loonen Nico Taverne Johanna J.Taverne-Thiele Dirkjan Schokker Mari A.Smits Alfons J.M.Jansman Jerry M.Wells Host Microbe Interactomics Group Wageningen University&ResearchDe Elst 16708 WD WageningenThe Netherlands Laboratory of Microbiology Wageningen University&ResearchStippeneng 46708 WE WageningenThe Netherlands Wageningen Livestock Research Wageningen University&ResearchDe Elst 16708 WD WageningenThe Netherlands

Here, we describe the use of monolayers of intestinal epithelial cells derived from intestinal organoids and transcriptomics to investigate the direct effects of dietary protein sources on epithelial function. Mechanically dissociated 3 D organoids of mouse duodenum were used to generate a polarized epithelium containing all cell types found in the tissue of origin. The organoid-derived cell monolayers were exposed to 4%(w/v) of ‘undigested(non-hydrolysed)-soluble' fraction of protein sources used as feed ingredients [soybean meal(SBM) and casein], or alternative protein sources(spray dried plasma protein, and yellow meal worm), or controls for 6 h prior to RNA isolation and transcriptomics. All protein sources altered expression of unique biological processes in the epithelial cells. Exposure of intestinal organoids to SBM downregulated expression of retinol and retinoid metabolic processes as well as cholesterol and lipid biosynthetic pathways, consistent with the reported hypotriglyceridaemic effect of soy protein in vivo. These findings support the use of intestinal organoids as models to evaluate complex interactions between dietary ingredients and the intestinal epithelium and highlights some unique host effects of alternative protein sources in animal feed and potentially human food.

关键词： Alternative protein sources Casein Intestinal organoids Organoids Soybean meal Spray dried plasma protein Transcriptomics Yellow meal worm

First-principles search of hot superconductivity in La-X-H ternary hydrides

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npj Computational Materials 2022年第1期8卷 1-8页

作者： Simone Di Cataldo Wolfgang von der Linden Lilia Boeri Institute of Theoretical and Computational physics Graz University of TechnologyNAWI Graz8010GrazAustria Dipartimento di Fisica Sapienza Universitàdi Roma00185RomaItaly Centro Ricerche Enrico Fermi Via Panisperna89a00184RomaItaly

Motivated by the recent claim of hot superconductivity with critical temperatures up to 550 k in La + x hydrides,we investigate the high-pressure phase diagram of compounds that may have formed in the experiment,using first-principles calculations for evolutionary crystal structure prediction and *** from the hypothesis that the observed T_(c) may be realized by successive heating upon a pre-formed LaH_(10) phase,we examine plausible ternaries of lanthanum,hydrogen and other elements present in the diamond anvil cell: boron,nitrogen,carbon,platinum,gallium,*** find that only boron and,to a lesser extent,gallium form metastable superhydride-like structures that can host high-T_(c) superconductivity,but the predicted T_(c)’s are incompatible with the experimental *** results indicate that,while the claims of hot superconductivity should be reconsidered,it is very likely that unknown H-rich ternary or multinary phases containing lanthanum,hydrogen,and possibly boron or gallium may have formed under the reported experimental conditions,and that these may exhibit superconducting properties comparable,or even superior,to those of currently known hydrides.

关键词： hydrides boron superconductivity

performance of the Montreal classification for inflammatory bowel diseases

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World Journal of Gastroenterology 2014年第41期20卷 15374-15381页

作者： Lieke M Spekhorst Marijn C Visschedijk Rudi Alberts Eleonora A Festen Egbert-Jan van der Wouden Gerard Dijkstra Rinse k Weersma Department of Gastroenterology and Hepatology University of Groningen and University Medical Centre Groningen Department of Genetics University of Groningen and University Medical Centre Groningen Department of Gastroenterology Isala Clinics Zwolle

AIM: To validate the Montreal classification system for Crohn’s disease (CD) and ulcerative colitis (UC) within the Netherlands.

关键词： Crohn’ s disease Ulcerative colitis Montreal classification phenotypes- inter-observer agreement