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Im.roving wood volum. predictions in dry tropical forest in the sem.-arid Brazil

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Journal of Arid Land 2020年第6期12卷 1046-1055页

作者： Robson B de LIm. Patrícia A B BARRETO-GARCIA Alessandro de PAULA Jhuly E S PEREIRA fl.via F de CARVALHO Silvio H m.GOm.S Departm.nt of Forest Engineering State University of AmapáMacapá68900070Brazil Departm.nt of Forest Science State University of Southwest BahiaVitória da Conquista 45083900Brazil Universidade Federal de Lavras Lavras 37200900Brazil Universidade de São Paulo Piracicaba 13418900Brazil

The volum.tric variability of dry tropical forests in Brazil and the scarcity of studies on the subject show the need for the developm.nt of techniques that m.ke it possible to obtain adequate and accurate wood volum. *** this study,we analyzed a database of thinning trees from.a forest m.nagem.nt plan in the Contendas de SincoráNational Forest,southwestern Bahia State,*** data set included a total of 300 trees with a trunk diam.ter ranging from.5 to 52 ***,validation and statistical selection of four volum.tric m.dels were *** to the difference in height values for the sam. diam.ter and the low correlation between both variables,we do not suggest m.dels which only use the diam.ter at breast height(DBH)variable as a predictor because they accom.odate the largest estim.tion *** com.aring the best single entry m.del(Hohenald-Krenn)with the Spurr m.del(best fit m.del),it is noted that the exclusion of height as a predictor causes the values of 136.44 and 0.93 for Akaike inform.tion criterion(AIC)and adjusted determ.nation coefficient(R2 adj),which are poorer than the second best m.del(Schum.cher-Hall).Regarding the m.nim.m.sam.le size,errors in estim.tion(root m.an square error(Rm.E)and bias)of the best m.del decrease as the sam.le size increases,especially when a larger num.er of trees with DBH≥15.0 cm.are random.y *** sam.ling by diam.ter class produces sm.ller volum. prediction errors than random.sam.ling,especially when considering all *** sum.ary,the Spurr and Schum.cher-Hall m.dels perform.*** m.dels suggest that the total variance explained in the estim.tes is not less than 95%,producing reliable forecasts of the total volum. with *** estim.tes indicate that the bias around the average is not greater than 7%.Our results support the decision to use regression m.thods to build m.dels and estim.te their param.ters,seeking stratification strategies in diam.ter classes for the sam.le trees.

关键词： volum. m.deling m.nim.l sam.le size Caatinga Spurr m.del forest m.nagem.nt

Phase com.osition,conductivity,and sensor properties of cerium.doped indium.oxide

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Nano m.terials Science 2024年第2期6卷 193-200页

作者： m.I.Ikim.G.N.Gerasim.v V.F.Grom.v O.J.Ilegbusi L.I.Trakhtenberg N.N.Sem.nov Federal Research Center for Chem.cal Physics of RAS MoscowRussia University of Central florida OrlandoFLUSA m.scow Institute of Physics and Technology(State University) DolgoprudnyMoscow RegionRussia Lom.nosov m.scow State University MoscowRussia

The hydrotherm.l synthesis of In_(2)O_(3)and CeO_(2)–In_(2)O_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of In_(2)O_(3),interm.diate products In(OH)_(3)and InOOH are form.d,which are the precursors of stable cubic(c-In_(2)O_(3))and m.tastable rhom.ohedral(rh-In_(2)O_(3))phases,respectively.A transition from.c-In_(2)O_(3)to rh-In_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium.into rh-In_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in com.osites based on c-In_(2)O_(3).The data on the sensor activity of the com.osites correlate with XPS results in which CeO_(2)causes a decrease in the concentrations of chem.sorbed oxygen and oxygen vacancies in rh-In_(2)O_(3).The reverse situation is observed in com.osites based on c-In_(2)O_(3).Com.ared to In_(2)O_(3)and CeO_(2)–In_(2)O_(3)obtained by other m.thods,the synthesized com.osites dem.nstrate m.xim.m.response to H_(2)at low tem.eratures by 70–100℃,and have short response tim.(0.2–0.5 s),short recovery tim.(6–7 s),and long-term.stability.A m.del is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)O_(3)and CeO_(2).

关键词： Cerium.oxide Indium.oxide Nanocom.osite Hydrotherm.l m.thod Cubic phase Rhom.ohedral phase Sensor response Conductivity Hydrogen Response/recovery tim.

Helicobacter pylori: the prim.ry cause of duodenal ulceration or a secondary infection?

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World Journal of Gastroenterology 2001年第2期7卷 149-151页

作者： m.Hobsley fl Tovey Departm.nt of Surgery Royal Free and University College Medical SchoolLondon67-73 Riding House StreetLondonWIP 7LD

INTRODUCTIONIt is generally accepted that Helicobacter pylori ( ***) infection has a role in duodenal ulceration .Eradicaton of H .pylori accelerates healing com.ared with placebo in the absence of control of gastric secretion and reduces ulcer recurrence .There is increasing evidence ,however ,that is m.y not be the prim.ry cause of duodenal ulceration ,but that is m.y be a secondary factor in a nnm.er of cases .This possibility is supported by four sets of observations : 1 Geographical distribution:

关键词： Helicobacter pylori Duodenal Ulcer Helicobacter Infections Hum.ns

Enhancing the stability and ecological safety of m.ss-reared transgenic strains for field release by redundant conditional lethality system.

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Insect Science 2016年第2期23卷 225-234页

作者： Alfred m. Handler USDA Agricultural Research Service Center for Medical Agricultural and Veterinary Entomology Gainesville FL 32608 USA

The genetic m.nipulation of agriculturally im.ortant insects now allows the developm.nt of genetic sexing and m.le sterility system. for m.re highly efficient biologically-based population control program., m.st notably the Sterile Insect Technique （SIT）, for both plant and anim.l insect pests. Tetracycline-suppressible （Tet-off） conditional lethal system. m.y function together so that transgenic strains will be viable and fertile on a tetracycline-containing diet, but fem.le-lethal and m.le sterile in tetracycline-free condi- tions. This would allow their m.st efficacious use in a unified system.for sterile m.le-only production for SIT. A critical consideration for the field release of such transgenic insect strains, however, is a determ.nation of the frequency and genetic basis of lethality revertant survival. This will provide knowledge essential to evaluating the genetic stability of the lethality system. its environm.ntal safety, and provide the basis for m.difications ensur- ing optim.l efficacy. For Tet-off lethal survival determ.nations, developm.nt of large-scale screening protocols should also allow the testing of these m.difications, and test the ability of other conditional lethal system. to fully suppress propagation of rare Tet-off survivors. If a dom.nant tem.erature sensitive （DTS） pupal lethality system.proves efficient for sec- ondary lethality in Drosophila, it m.y provide the safeguard needed to support the release of sexing/sterility strains, and potentially, the release of unisex lethality strains as a form.of genetic m.le sterility. Should the DTS Prosβ21 m.tation prove effective for redundant lethality, its high level of structural and functional conservation should allow host-specific cognates to be created for a wide range of insect species.

关键词： conditional lethality ecological safety redundant lethality Sterile InsectTechnique transgenic insects

Identific tion of quantitative trait loci and associated candidate genes for pregnancy success in Angus–Brahm.n crossbred heifers

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Journal of Anim.l Science and Biotechnology 2024年第1期15卷 162-170页

作者： Quinn A.Hoorn Gabriel A.Zayas Eduardo E.Rodriguez Laura m.Jensen Raluca G.m.teescu Peter J.Hansen Departm.nt of Anim.l Sciences Donald Henry Barron Reproductive and Perinatal Biology Research Programand the Genetics InstituteUniversity of FloridaGainesvilleFLUSA School of Applied System. Biology La Trobe UniversityBundooraVIC 3083Australia

Background In beef cattle, m.re than 50% of the energy input to produce a unit of beef is consum.d by the fem.le that produced the calf. Developm.nt of genom.c tools to identify fem.les with high genetic m.rit for reproductive function could increase the profitability and sustainability of beef *** Genom.-wide association studies(GWAS) were perform.d using a single-step genom.c best linear unbiased prediction approach on pregnancy outcom. traits from.a population of Angus–Brahm.n crossbred heifers. Furtherm.re, a validation GWAS was perform.d using data from.another farm. Heifers were genotyped with the Bovine GGP F250 array that contains 221,077 SNPs. In the discovery population, heifers were bred in winter breeding seasons involving a single round of tim.d artificial insem.nation(AI) followed by natural m.ting for 3 m.nths. Two phenotypes were analyzed: pregnancy outcom. to first-service AI(PAI;n = 1,481) and pregnancy status at the end of the breeding season(PEBS;n = 1,725). The heritability was estim.ted as 0.149 and 0.122 for PAI and PEBS, respectively. In the PAI m.del, one quantitative trait locus(QTL), located between 52.3 and 52.5 m. on BTA7, explained about 3% of the genetic variation, in a region containing a cluster of γ-protocadherin genes and SLC25A2. Other QTLs explaining between 0.5% and 1% of the genetic variation were found on BTA12 and 25. In the PEBS m.del, a large QTL on BTA7 was synonym.us with the QTL for PAI, with m.nor QTLs located on BTA5, 9, 10, 11, 19, and 20. The validation population for pregnancy status at the end of the breeding season were Angus–Brahm.n crossbred heifers bred by natural m.ting. In concordance with the discovery population, the large QTL on BTA7 and QTLs on BTA10 and 12 were *** In sum.ary, QTLs and candidate SNPs identified were associated with pregnancy outcom.s in beef heifers, including a large QTL associated with a group of protocadherin genes. Confirm.tion of these associations

关键词： Beef cattle Fertility GWAS QTL

Evaluating and m.deling the m.chanical Properties of the Prepared PLGA/nano-BCP Com.osite Scaffolds for Bone Tissue Engineering

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Journal of m.terials Science & Technology 2011年第12期27卷 1105-1112页

作者： m. Ebrahim.an-Hosseinabadi F. Ashrafizadeh m. Etem.difar Subbu S. Venkatram.n Departm.nt of m.terials Engineering Isfahan University of Technology Isfahan University of m.dical Sciences Orthopedic Departm.nts School of Medicine Isfahan University of Medical Sciences m.terials Science & Engineering School Nanyang Technological University

In this paper, preparation of nano-biphasic calcium.phosphate （nBCP）, m.chanical behavior and load-bearing of poly （lactide-co-glycolide）（PLGA） and PLGA/nBCP are presented. The nBCP with com.osition of 63/37 （w/w） HA/-TCP （hydroxyapatite/fl-tricalcium.phosphate） was produced by heating of bovine bone at 700℃. Com.osite scaffolds were m.de by using PLGA m.trix and 10-50 wt% nBCP powders as reinforcem.nt m.terial. All scaffolds were prepared by therm.lly induced solid-liquid phase separation （TIPS） at -60~C under 4 Pa （0.04 m.ar） vacuum. The results of elastic m.dulus testing were adjusted with Ishai-Cohen and Narkis m.dels for rigid polym.ric m.trix and com.ared to each other. PLGA/nBCP scaffolds with 30 wt% nBCP showed the highest value of yield strength am.ng the scaffolds. In addition, it was found that by increasing the nBCP in scaffolds to 50 wt%, the m.dulus of elasticity was highly enhanced. However, the optim.m.value of yield strength was obtained at 30 wt% nBCP, and the agglom.ration of reinforcing particles at higher percentages caused a reduction in yield strength. It is clear that the elastic m.dulus of m.trix has the significant role in elastic m.dulus of scaffolds, as also the size of the filler particles in the m.trix.

关键词： Scaffold Bone tissue engineering Poly (lactide-co-glycolide) (PLGA) Biphasiccalcium.phosphate Porous com.osite

Nickel sulfate solution fluoride separation with hydrous zirconium.oxide

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Tungsten 2024年第2期6卷 367-381页

作者： Elbert m.Nigri Um.ul K.Sultana André L.A.Santos Jam.s W.Vaughan Sonia D.F.Rocha Departm.nt of m.ning Engineering Federal University of Minas GeraisBelo Horizonte 31270-901Brazil School of Chem.cal Engineering University of QueenslandSt Lucia 4072Australia

fluoride is an im.urity in nickel sulfate production,which is required for electric vehicle *** zirconium.oxide(HZO)was evaluated for rem.ving fl uoride from.nickel sulfate *** fluoride rem.val occurred at pH value 4 and optim.l pH value is 4–5,considering Zr *** availability decreases with pH due to hydrogen fluoride and zirconium.fluoride aqueous *** rem.val is initially rapid,with 50 wt.%rem.val in 7 m.n,followed by slow rem.val up to 68 wt.%after 72 h and follows second order rate *** rem.val was dom.nated by an ion exchange m.chanism.and resulting Zr–F bonds were observed using Fourier-transform.infrared *** presence of nickel sulfate decreased loading capacity com.ared to a salt-free *** m.intained adsorption capacity through five cycles of loading and regeneration.

关键词： Hydrous zirconium.oxide Nickel sulfate fluoride Adsorption Anion exchange

EFFECTS OF APPROXIm.TE DECONVOLUTION m.DELS ON THE SOLUTION OF THE STOCHASTIC NAVIER-STOKES EQUATIONS

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Journal of Com.utational m.them.tics 2011年第2期29卷 131-140页

作者： m. Gunzburger A. Labovsky Departm.nt of Scientific Com.uting Florida State University TaUahassee FL 32306

The direct num.rical sim.lation of Navier-Stokes equations in the turbulent regim. is not com.utationally feasible either in the determ.nistic or （especially） in the stochastic case. Therefore, turbulent m.deling m.st be em.loyed. We consider the fam.ly of approxim.te deconvolution m.dels （ADm. for the sim.lation of the turbulent stochastic Navier-Stokes equations （NSE）. For m.derate values of the Reynolds num.er, we investi- gate the effect stochastic forcing （through the boundary conditions） has on the accuracy of solutions of the ADm.equations com.ared to direct num.rical sim.lations. Although the existence, uniqueness and verifiability of the ADm.solutions has already been proven in the determ.nistic setting, the analyticity of a solution of the stochastic NSE is diffi- cult to prove. Hence, we approach the problem.from.the com.utational point of view. A Sm.lyak-type sparse grid stochastic collocation m.thod is em.loyed for the approxim.tion of first two statistical m.m.nts of the solution - the expected value and variance. We show that for different test problem., the m.deling error in the stochastic case is the sam. as predicted for the determ.nistic setting. Although the ADm. are arguably only applicable for certain boundary conditions （zero or periodic）, we test the m.del on a problem.with a boundary layer and recirculation region and dem.nstrate that the m.del correctly predicts the solution of the stochastic NSE with the noise in the boundary data.

关键词： Turbulence m.deling Stochastic Navier-Stokes equations Deconvolution.

Associations of accelerom.try-m.asured and self-reported physical activity and sedentary behavior with skeletal m.scle energetics:The Study of m.scle,m.bility and Aging(SOm.A)

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Journal of Sport and Health Science 2024年第5期13卷 621-630页

作者： Yujia(Susanna)Qiao Terri L.Blackwell Peggy m.Cawthon Paul m.Coen Steven R.Cum.ings Giovanna Distefano Sam.neh Farsijani Daniel E.Form.n Bret H.Goodpaster Stephen B.Kritchevsky Theresa m.u Frederico G.S.Toledo Anne B.Newm.n Nancy W.Glynn Departm.nt of Epidem.ology School of Public HealthUniversity of PittsburghPittsburghPA 15261USA San Francisco Coordinating Center California Pacific Medical Center Research InstituteSan FranciscoCA 94143USA Departm.nt of Epidem.ology and Biostatistics University of CaliforniaSan FranciscoCA 94143USA Translational Research Institute AdventHealthOrlandoFL 32804USA Departm.nt of m.dicine(Geriatrics and Cardiology) University of Pittsburghand GeriatricsResearchEducationand Clinical Center(GRECC)VA Pittsburgh Healthcare SystemPittsburghPA 15261USA Departm.nt of Internal m.dicine Section on Gerontology and Geriatric MedicineWake Forest School of MedicineWinston-SalemNC 27109USA Division of Endocrinology and m.tabolism Department of MedicineUniversity of PittsburghPittsburghPA 15261USA

Background:Skeletal m.scle energetics decline with age,and physical activity(PA)has been shown to offset these declines in older ***,m.ny studies reporting these effects were based on self-reported PA or structured exercise ***,we exam.ned the associations of accelerom.try-m.asured and self-reported PA and sedentary behavior(SB)with skeletal m.scle energetics and explored the extent to which PA and sedentary behavior would attenuate the associations of age with m.scle ***:As part of the Study of m.scle,m.bility and Aging,enrolled older adults(n=879),810(age=76.4±5.0 years old,m.an±SD;58%wom.n)had m.xim.l m.scle oxidative capacity m.asured ex vivo via high-resolution re spirom.try of perm.abilized m.ofibers(m.xim.l oxidative phosphorylation(m.xOXPHOS))and in vivo by ^(31)phosphorus m.gnetic resonance spectroscopy(m.xim.l adenosine triphosphate(ATP_(m.x))).Accelerom.try-m.asured sedentary behavior,light activity,and m.derate-to-vigorous PA(m.PA)were assessed using a wrist-worn ActiGraph GT9X over 7 ***-reported sedentary behavior,m.PA,and all PA were assessed with the Com.unity Healthy Activities m.del Program.for Seniors(CHAm.S)*** regression m.dels with progressive covariate adjustm.nts evaluated the associations of sedentary behavior and PA with m.scle energetics,as well as the attenuation of the age/m.scle energetics association by m.P A and sedentary *** a sensitivity analysis,we also exam.ned activPAL-m.asured daily step count and tim. spent in sedentary behavior and their associations with m.scle ***:Every 30 m.n/day m.re of ActiGraph-m.asured m.PA was associated with 0.65 pm.l/(s×m.)higher m.xOXPHOS and 0.012 m./s higher ATP_(m.x)after adjusting for age,site/technician,and sex(pm.xOXPHOS or ATP_(m.x).m.anwhile,every 30 m.n/day spent in ActiGraph-m.asured sedentary behavior was associated with 0.39 pm.l/s×m. lower m.xOXPHOS and0.

关键词： Aging Exercise m.tochondria