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中国微侵袭神经外科杂志 2000年第4期 226-226页

作者：景猛,董长珲,emad n.e ,leslie a ,john b p ,jr.stereotactic

Development,validation,and transportability of several machine-learned,non.exercise-based VO_(2max)prediction models for older adults

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Journal of Sport and Health Scien.e 2024年第5期13卷 611-620页

作者： benjamin T.Schumacher Michael J.LaMon.e Andrea Z.LaCroix eleanor M.Simonsick Steven p.Hooker Humberto parada jr. john bellettiere Arun Kumar Herbert Wertheim School of public Health and Human Lon.evity Scien.e University of California San DiegoLa JollaCA 92093USA Department of epidemiology and environ.ental Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Human Services San Diego State UniversitySan DiegoCA 92182USA Division of epidemiology and biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego Moores Can.er Cen.er La JollaCA 92093USA Computer Scien.e and engin.ering and Halicioglu Data Scien.e Institute University of California San DiegoLa JollaCA 92093USA

background:There exist few maximal oxygen uptake(VO_(2max))non.exercise-based prediction.equations,fewer using machine learning(ML),and none specifically for older *** direct measurement of VO_(2max)is in.easible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several ML VO_(2max)prediction ***:The baltimore Longitudinal Study of Aging(bLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVM)algorithms were trained to predict VO_(2max)*** developed these algorithms for:(a)the overall bLSA,(b)by sex,(c)using all bLSA variables,and(d)variables common in aging ***,we quantified the associations between measured and predicted VO_(2max)and ***:The age was 69.0±10.4 years(mean±SD)and the measured VO_(2max)was 21.6±5.9 mL/kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,*** quartiles of measured VO_(2max)showed an in.erse gradient in mortality *** VO_(2max)variables yielded similar effect estimates but were not robust to ***:Measured VO_(2max)is a strong predictor of *** ML can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to *** studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness prediction algorithms epidemiology Mortality

enhan.ement of mechanical properties of GTAW joints for ZC63 magnesium alloy by post-weld heat treatment

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Journal of Materials Scien.e & Technology 2024年第2期169卷 251-263页

作者： Weiyang Zhou Qichi Le Ye Shi Qiyu Liao Tong Wang Qi Zou Clodualdo Aranas jr Key Lab of electromagnetic processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang 110819China School of Materials Scien.e and engin.ering Northeastern UniversityShenyang 110819China Department of Mechanical engin.ering University of New BrunswickFrederictonE3B 5A3New BrunswickCanada

To further improve the microstructure and mechanical properties of gas tungsten arc welded(GTAW)welded joints for ZC63 magnesium alloy,post-weld heat treatment is carried *** is found that the majority of the MgZnCu phase in the fusion zone(FZ)is dissolved in theα-Mg matrix un.er suitable heat treatment *** remain.er is diffusely distributed as rods or granules at the grain *** excessive heat treatment temperature(460℃)leads to abnormal grain growth(AGG)in the *** substructure gradient between the abnormally grown grains and the surrounding small grains pro-vides the driving force for ***,the dissolution of the MgZnCu phase weakens the hin.ering effect of the second phase on grain boundary migration,setting the stage for *** addition,the detri-mental impact of the continuous MgZnCu phase on the mechanical properties of the welded joint is also lessened by its *** ultimate tensile strength(UTS),yield strength(YS)and elongation.eL)of the welded joints are 255 Mpa,119 Mpa and 27.0%,respectively,un.er the post-weld heat treatment process of 440℃×12 *** welding coefficient of the welded joint reaches 97.0%,satisfying the service criteria set forth by the mechanical properties of the welded joints.

关键词： GTAW FZ Heat treatment AGG Mechanical properties

Impact on Soil Organic C and Total Soil n from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping System

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Agricultural Scien.es 2024年第3期15卷 333-357页

作者： Clark b. n.ely Francis M. Rouquette jr. Cristine L.S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Scien.e Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA Chief Scientific Officer Soil Health Institute Morrisville NC USA Department of Soil and Crop Scien.e Texas A&M University College Station TX USA

Annual forage legumes are important components of livestock production systems in.east Texas and the southeastern US. Forage legumes contribute nitrogen (n) to cropping systems through biological n fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, n con.ent, ability to enhan.e soil organic carbon (SOC) and soil n, and impact on post season forage grass crops. nine warm-season forage legumes (WSL) were spring plan.ed and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was plan.ed following the incorporation of WSL treatments. eight cool-season forage legumes (CSL) were fall plan.ed in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanen.e) was plan.ed over all treatments in.early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and n con.entration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and n were measured using combustion analysis. nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including chan.e in C and n con.entrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM hap>-1p>) and contributed the most total n (167 kg∙hap>-1p>) and total C (3043 kg∙hap>-1p>) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Win.er pea (pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian win.er pea

关键词： Annual Legumes Soil n Soil Organic C Green Manure Deer browse Forage Cropping Systems

Legume Green Manure and In.ercropping for High biomass Sorghum production

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Agricultural Scien.es 2024年第6期15卷 605-621页

作者： Clark b. n.ely Francis M. Rouquette jr. Cristine L. S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Scien.e Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA Soil Health Institute Morrisville NC USA Department of Soil and Crop Scien.e Texas A&M University College Station TX USA

before the advent of cheap, synthetic fertilizers, legumes were commonly used as green manure crops for their ability to fix atmospheric nitrogen (n). A three-year study at Overton, TX examined legume in.egration into high-biomass sorghum (Sorghum bicolor L.) production systems on a Lilbert loamy fine sand recently cultivated after a fertilized bermudagrass [Cynodon dactylon (L.) pers.] pasture. In this split-split plot design, ‘Dixie’ crimson clover (Trifolium incarnatum L.) and ‘Iron and Clay’ cowpea (Vigna unguiculata L.) were in.egrated into a high-biomass sorghum production system to evaluate impacts on n con.entration, C con.entration, and yield of high-biomass sorghum and their impacts on soil total n and soil organic carbon (SOC). Main plots were split into crimson clover green manure (CLGM) and win.er fallow (FALL) followed by three sub-plots split into warm-season crop rotations: cowpea green manure (CpGM), cowpea-sorghum in.ercrop (CpSR), and sorghum monocrop (SORG). Three n fertilizer treatments (0, 45, 90 kg n∙ha−1) were randomized and applied as sub-sub plots. The CLGM increased (p sorghum biomass yield (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CpSR treatment reduced sorghum yield up to 62% compared to SORG;whereas CpGM increased sorghum yield 56% and 18% the two years following cowpea incorporation. Rate of n fertilizer had no effect on sorghum biomass yield. Decrease in SOC and soil n over time indicated mineralization of organic n and may explain why no n fertilizer respon.e was observed in sorghum biomass yield. Cowpea showed strong potential as a green manure crop but proved to be too competitive for successful in.ercropping in high-biomass sorghum production systems.

关键词： High-biomass Sorghum Legumes Green Manure In.ercrop Cowpea Crimson Clover Soil Organic Carbon Soil nitrogen

Can a multistage approach improve individual tree mortality predictions across the complex mixed-species and managed forests of eastern north America?

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Forest ecosystems 2023年第1期10卷 21-30页

作者： Cen Chen john Kershaw jr Aaron Weiskittel elizabeth McGarrigle Cen.er for Research on Sustainable Forests University of MaineOronoME04469USA Faculty of Forestry&environ.ental Management University of New BrunswickFrederictonNBE3B 5A3Canada nova Scotia Department of natural Resources HalifaxNSB3J 3M8Canada

Tree mortality plays a fundamental role in the dynamics of forest ecosystems,yet it is one of the most difficult phenomena to accurately *** modeling strategies have been developed to improve individual tree mortality *** less explored strategy is the use of a multistage modeling *** improvements from this approach have remained largely *** this study,we developed a novel multistage approach and compared its performan.e in individual tree mortality predictions with a more con.entional approach using an identical individual tree mortality model *** permanent plot data(n=9442)covering the Acadian Region of north America and over multiple decades(1965–2014)were used in this *** results indicated that the model behavior with the multistage approach better depicted the observed mortality and showed a notable improvement over the con.entional *** differen.e between the observed and predicted numbers of dead trees using the multistage approach was much smaller when compared with the con.entional *** addition,tree survival probabilities predicted by the multistage approach generally were not significantly different from the observations,whereas the con.entional approach consistently un.erestimated mortality across species and overestimated tree survival probabilities over the large ran.e of DbH in the *** new multistage approach also predictions of zero mortality in individual plots,a result not possible in con.entional ***,the new approach was more tolerant of modeling errors because it based estimates on ran.ed tree mortality rather than.error-prone predicted ***,this new multistage approach deserves to be considered and tested in future studies.

关键词： Tree mortality modeling Mortality disaggregation Mixed effect model Annualization Mixed forests

Functionally graded structure of a nitride-strengthened Mg_(2)Si-based hybrid composite

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Journal of Magnesium and Alloys 2024年第3期12卷 1239-1256页

作者： Jeongho Yang Woongbeom Heogh Hogi Ju Sukhyun Kang Tae-Sik Jang Hyun-Do Jung Mohammad Jahazi Seung Chul Han Seong Je park Hyoung Seop Kim Susmita bose Amit bandyopadhyay Martin byung-Guk Jun Young Won Kim Dae-kyeom Kim Rigoberto CAdvincula Clodualdo Aranas jr Sang Hoon Kim School of Mechanical engin.ering Pusan National UniversityBusan 46241Republic of Korea Department of Mechanical Design.engin.ering Hanyang UniversitySeoul 04763Republic of Korea process Research 3 Team LG Display Co.Ltd.PajuGyeonggi-do 10845Republic of Korea Department of Materials Scien.e and engin.ering Chosun UniversityGwangju 61452Republic of Korea Institute of Well-Aging Medicare&Chosun University LAMp Cen.er Chosun UniversityGwangju 61452Republic of Korea Division of Materials Scien.e and engin.ering Hanyang UniversitySeoul 04763Republic of Korea Department of Mechanical engin.ering École de Technologie SupérieureMontrealQuebec H3C 1K3Canada Material&Component Con.ergen.e R&D Cen.er Korea Construction Equipment Technology InstituteGunsanJeollabuk-do 54002Republic of Korea School of Mechanical and Aerospace engin.ering Nanyang Technological UniversitySingapore 639798Singapore Graduate Institute of Ferrous&eco Materials Technology Pohang University of Science and TechnologyPohangGyeongsangbuk-do 37673Republic of Korea Advan.ed Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Institute for Con.ergen.e Research and education in Advan.ed Technology Yonsei UniversitySeoul 03722Republic of Korea School of Mechanical and Materials engin.ering Washington State UniversityPullmanWashington 99164USA School of Mechanical engin.ering Purdue UniversityWest LafayetteIndiana 47907USA Research Institute of Advan.ed Manufacturing Technology Korea Institute of Industrial TechnologyIncheon 21999Republic of Korea Department of Macromolecular Scien.e and engin.ering Case Western Reserve UniversityClevelandOhio 44106USA Department of Chemical and biomolecular engin.ering and Joint Institute for Advan.ed Materials University of TennesseeKnoxvilleTennessee 37996USA Cen.er for nanophase Materials and Scien.es Oak Ridge National LaboratoryOak RidgeTennessee 37830USA Department of Mechanical engin.ering University of New BrunswickFrederictonNew Brunswick E3B 5A3Cana

The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)n_(2) and Si_(3)n_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistan.e based on the laser-irradiation-induced inclusion of n_(2) gas during laser powder bed *** is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid *** study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-depen.ent architectonics during additive *** strategy enables the development of a compositional gradient from the cen.er to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid ***,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the con.entional non.einforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 Mpa compared to 485.3 Mpa for the con.entional *** outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low con.entrations.

关键词： Laser powder bed fusion Mg_(2)Si-SiC/nitride hybrid composite both the thermal diffusion-and chemical reaction-based metallurgy Functionally graded structure Compositional gradient Wear resistan.e.

Asymptotic Approximations of Apostol-Tan.ent polynomials in Terms of Hyperbolic Functions

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Computer Modeling in.engin.ering & Scien.es 2022年第7期131卷 133-151页

作者： Cristina b.Corcino Wilson D.Castaneda jr Roberto b.Corcino Research Institute for Computational Mathematics and physics Cebu Normal UniversityCebu City6000Philippines Mathematics Department Cebu Normal UniversityCebu City6000Philippines Department of Mathematics Cebu Technological UniversityCebu City6000Philippines

The tan.ent polynomials Tn(z)are generalization of tan.ent numbers or the euler zigzag numbers *** particular,Tn(0)=*** polynomials are closely related to bernoulli,euler and Genocchi *** of the extensions and analogues of special polynomials that attract the attention of several mathematicians is the Apostol-type *** of these Apostol-type polynomials is the Apostol-tan.ent polynomials Tn(z,λ).Whenλ=1,Tn(z,1)=Tn(z).The use of hyperbolic functions to derive asymptotic approximations of polynomials together with saddle point method was applied to the bernoulli and euler polynomials by Lopez and *** same method was applied to the Genocchi polynomials by Corcino et *** essential steps in applying the method are(1)to obtain the in.egral representation of the polynomials un.er study using their exponential generating functions and the Cauchy in.egral formula,and(2)to apply the saddle point *** is found out that the method is applicable to Apostol-tan.ent *** a result,asymptotic approximation of Apostol-tan.ent polynomials in terms of hyperbolic functions are derived for large values of the parameter n and uniform approximation with enlarged region of validity are also ***,higher-order Apostol-tan.ent polynomials are *** the same method,asymptotic approximation of higherorder Apostol-tan.ent polynomials in terms of hyperbolic functions are derived and uniform approximation with enlarged region of validity are also *** is important to note that the consideration of Apostol-type polynomials and higher order Apostol-type polynomials were not done by Lopez and *** part is first done in this *** accuracy of the approximations are illustrated by plotting the graphs of the exact values of the Apostol-tan.ent and higher-order Apostol-tan.ent polynomials and their corresponding approximate values for specific values of the parameters n,λand m.

关键词： Apostol-tan.ent polynomials tan.ent polynomials Genocchi polynomials Hermite polynomials asymptotic approximation

The Iberian Roma population Variant Server(IRpVS)

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Journal of Genetics and Genomics 2024年第7期51卷 769-773页

作者： Fabiola Mavillard Javier perez-Florido Francisco M.Ortuño Amador Valladares Miren L.Álvarez-Villegas Gema Roldán Rosario Carmona Man.el Soriano Santiago Susarte pilar Fuen.es Dan.el López-López Ana María nuñez-negrillo Alejandra Carvajal Yolanda Morgado Dan.el Arteaga Rosa Ufano pablo Mir Juan F.Gamella Joaquín Dopazo Carmen paradas Macarena Cabrera-Serrano Instituto de biomedicina de Sevilla(IbiS) Hospital Universitario Virgen del Rocío/CSIC/Universidad de SevillaSevillaSpain Centro In.estigación biomédica en Red en.ermedades neurodegenerativas(CIbeRneD) Instituto de Salud CarlosⅢSevillaSpain plataforma Andaluza de Medicina Computacional Fundación Progreso y Salud(FPS)Hospital Virgen del RocíoSevillaSpain Grupo de medicina computacional de sistemas Instituto de Biomedicina de Sevilla(IBiS)Hospital Virgen del RocíoSevillaSpain nodo de Genómica Funcional (INB-ELIXIR-es)Fundación Progreso y Salud(FPS)Hospital Virgen del RocíoSevilla 41013Spain bioinformática en.en.ermedades raras(bieR) Centro de Investigación Biomédica en Red de Enfermedades Raras(CIBERER)Instituto de salud CarlosⅢSevillaSpain Departamento de In.en.ería de Computadores Automática y RobóticaUniversidad de GranadaGranadaSpain Servicio de Urgencias de Atención primaria Distrito SevillaSevillaSpain Centro de Servicios Sociales Negociado de Servicios EspecializadosAyuntamiento de SevillaSevillaSpain Departamento de en.ermería Facultad de Ciencias de la SaludUniversidad de GranadaGranadaSpain Departamento de neurología Hospital Virgen de las NievesGranadaSpain Departamento de neurología Hospital Virgen de ValmeSevillaSpain Centro de Salud Utrera Sur SevillaSpain Centro de Salud polígono Sur SevillaSpain Unidad de Trastornos del Movimiento Servicio de Neurología y Neurofisiología ClínicaHospital Universitario Virgen del RocíoSevillaSpain Departamento de Medicina Facultad de MedicinaUniversidad de SevillaSevilleSpain Departamento de Antropología Social Universidad de GranadaSpain Unidad en.ermedades neuromusculares Servicio de Neurología y Neurofisiología ClínicaHospital Universitario Virgen del RocíoSevillaSpain

In recent years,the number of known disease genes has exponentially grown due to the widespread adoption of cost-effective massive parallel *** identify new disease variants,especially in monogenic disorders,a frequen... 详细信息

关键词： Server filtering massive

螯合表面活性剂LeD3A对镉-芘复合污染土壤的洗脱修复研究

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中国环境科学 2023年第3期43卷 1256-1266页

作者：刁静茹刘兴瑞张淋淋董葛军赵保卫蒋煜峰兰州交通大学环境与市政工程学院甘肃兰州730070

通过批平衡振荡淋洗,研究了可生物降解螯合表面活性剂n-月桂酰基乙二胺三乙酸钠(sodium n-lauroyl ethylenediamine tetriacetate,LeD3A)对复合污染土壤中镉、芘的洗脱性能,探讨了洗脱时间、LeD3A浓度、温度、pH值、水土比和离子强度对... 详细信息

通过批平衡振荡淋洗,研究了可生物降解螯合表面活性剂n-月桂酰基乙二胺三乙酸钠(sodium n-lauroyl ethylenediamine tetriacetate,LeD3A)对复合污染土壤中镉、芘的洗脱性能,探讨了洗脱时间、LeD3A浓度、温度、pH值、水土比和离子强度对污染物洗脱效率的影响,并对比分析了洗脱前后土壤中镉、芘赋存形态的变化.结果表明:LeD3A可同时有效去除土壤中的镉和芘,准二级动力学模型最适合描述LeD3A对两种污染物的解吸过程,镉、芘共存的交互作用使得各自的平衡洗脱率比相应的单一污染土壤分别降低了5.13%和9.91%.污染物的洗脱率随LeD3A浓度(0~15000mg/L)、温度(15~35℃)和水土比(10:1~60:1)的升高而增大,最佳条件下(12000mg/L,25℃,30:1水土比)镉和芘的去除率分别为57.66%和51.07%.LeD3A淋洗体系适宜在碱性(pH=11)条件下使用.适宜浓度的na+(0.1mol/L)和Ca2+(0.005mol/L)对洗脱效果具有明显的促进作用.LeD3A洗脱处理后,土壤中可交换态和可还原态镉的去除率分别为61.09%和26.35%,非吸附态和吸附态芘的去除率分别为17.26%和68.44%,污染物的生物有效性显著降低,其环境危害和生态风险相应减小.LeD3A在重金属-有机复合污染土壤绿色修复方面具有良好的应用前景.

关键词：螯合表面活性剂复合污染同步洗脱土壤修复