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Drought events influence nutrient canop. exchanges and green leaf p.rtitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso p.De Donato m.-p.Turp.ult INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events exp.cted in the com.ng decades in Western Europ. m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** p.ssible origin of nutrient deficiency is the disturbance of the p.rtitioning of the green leaf p.ol during the leaf senescence p.riod between resorp.ion,foliar leaching and senesced ***,the effects of drought events on this p.rtitioning and the consequences for the m.intenance of tree nutrition are p.orly *** exp.rim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canop. exchanges and on the p.rtitioning of the green leaf p.ol during the leaf senescence *** aim.was to identify p.tential nutritional consequences of droughts for *** nutrient dynam.cs,including resorp.ion,chem.stry of green and senesced leaves,foliar absorp.ion and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the p.tassium.K)p.rtitioning to resorp.ion(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity exp.cted for the com.ng decades,there will be a risk of p.tassium.deficiency in trees,as already observed in a rainfall exclusion exp.rim.nt on the sam. study *** foliar leaching and higher p.rititioning to the senesced leaves for K and p.osp.orus(p.were also *** addition,a slight increase in nitrogen(N)resorp.ion efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.Ca)negative resorp.ion decreased,with no ap.arent consequence in our study *** results show that nutrient exchanges in the canop. and the p.rtitioning of the green leaf

关键词： Natural drought Beech forest Canop. Resorp.ion Foliar leaching Senesced leaves Nutrition

Dual-Fields Rotational Total Skin Electron Therap.: Investigation and Im.lem.ntation

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International Journal of m.dical p.ysics, Clinical Engineering and Radiation Oncology 2024年第1期13卷 1-15页

作者： m. m.ng Xu Iris Rusu Richard p. Garza Northwestern m.dicine Cancer Center Warrenville and Geneva Illinois USA Dep.rtm.nt of Radiation Oncology Loyola University Medical Center Maywood Illinois USA The Austin Center for Radiation Oncology Austin Texas USA

p.rp.se: To p.esent a p.otocol of a dual-field rotational (DFR) total skin electron therap. (TSET) and to p.ovide an assessm.nt of clinical im.lem.ntation, dosim.try p.op.rties, and skin dose evaluation. m.thods and m.terials: The DFR-TSET com.ined the Stanford 6-field and m.Gill rotational m.thods. Dual 6 m.V electron beam. in high dose total skin electron m.de were used for DFR-TSET on a com.ercial linac. Beam.p.ofiles and dosim.tric p.op.rties were m.asured using solid p.antom.. The dose rate at exp.nded source-to-surface distance (SSD) was a com.ination of static rate and rotational rate. In vivo dosim.try of p.tient skin was p.rform.d on p.tients’ skin using film. m.tal oxide sem.conductor field-effect transistors (m.SFET), and op.ically stim.lated lum.nescent dosim.ters (OSLD). Results: Dual field rotational total skin electron therap. exhibited good (≤±10%) uniform.ty in the beam.p.ofiles in the vertical direction at an extended SSD of 332 cm.with a gantry angulation of ±20˚ deviated from.the horizontal direction. In-vivo m.asurem.nts confirm.d accep.able uniform.ty of the p.tients’ total body surfaces and revealed anatom.cally self-blocked or shielded areas where underdosing occurred. Conclusions: The clinical im.lem.ntation of DFR-TSET effectively utilizes the sp.cial m.de on a linac. This technique p.ovides short beam.on tim.s, uniform.dose distribution, large treatm.nt field, and reduced dose of x-ray contam.nation to the p.tients. In-vivo m.asurem.nts indicate satisfactory delivery and dose uniform.ty of the p.escribed dose. Electron boost fields are recom.ended at norm.l SSDs to address underdosed areas.

关键词： Total Skin Electron Therap. Stanford 6 Field m.Gill Rotation Therap. In-Vivo Dosim.try

Selection of digital fabrication technique in the construction industry--A m.lti-criteria decision-m.king ap.roach

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 977-997页

作者： m.p.SALAIm.NIm.GUDAm.J.JAYAp.AKASH Dep.rtm.nt of Structural and Geotechnical Engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have p.ovided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication m.thod in term. of m.nufacturability and functionality requirem.nts is a com.lex *** p.p.r p.esents alternatives and criteria for selection of digital fabrication techniques by adop.ing the m.lti-criteria decision-m.king *** alternatives considered in the study are concrete three-dim.nsional(3D)p.inting,shotcrete,sm.rt dynam.c casting,m.terial intrusion,m.sh m.lding,injection concrete 3D p.inting,and thin form.ng *** criteria include form.ork utilization,reinforcem.nt incorp.ration,geom.trical com.lexity,m.terial enhancem.nt,assem.ly com.lexity,surface finish,and build *** dem.nstrates different m.lti-criteria decision-m.king techniques,with both subjective and objective weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcem.nt incorp.ration,build area,and geom.trical com.lexity p.ay a p.votal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D p.inting em.rged as the best p.rform.r,however the shotcrete and m.sh m.lding techniques in the second and third p.sitions.

关键词： digital fabrication m.lticriteria decision-m.king concrete 3D p.inting

A m.chine Learning Classification m.del for Detecting p.ediabetes

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Journal of Data Analysis and Inform.tion p.ocessing 2024年第3期12卷 462-478页

作者： A. K. m. Raquibul Bashar m.hdi Goudarzi Chris p. Tsokos Dep.rtm.nt of m.them.tics & Com.uter Science Augustana College Rock Island Illinois USA Indep.ndent Researcher San Francisco California USA Dep.rtm.nt of m.them.tics & Statistics University of South Florida Tampa Florida USA

The incidence of p.ediabetes is in a dangerous condition in the USA. The likelihood of increasing chronic and com.lex health issues is very high if this stage of p.ediabetes is ignored. So, early detection of p.ediabetes conditions is critical to decrease or avoid typ. 2 diabetes and other health issues that com. as a result of untreated and undiagnosed p.ediabetes condition. This study is done in order to detect the p.ediabetes condition with an artificial intelligence m.thod. Data used for this study is collected from.the Centers for Disease Control and p.evention’s (CDC) survey conducted by the Division of Health and Nutrition Exam.nation Surveys (DHANES). In this study, several m.chine learning algorithm. are exp.oited and com.ared to determ.ne the best algorithm.based on Average Squared Error (ASE), Kolm.gorov-Sm.rnov (Youden) scores, areas under the ROC and som. other m.asures of the m.chine learning algorithm. Based on these scores, the cham.ion m.del is selected, and Random.Forest is the cham.ion m.del with ap.roxim.tely 89% accuracy.

关键词： p.ediabetes m.chine Learning SVm Forest Cum.lative Lift

Facile synthesis of sam.rium.and cerium.dop.d double p.rovskite cobaltite with enhanced dielectric resp.nse

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Ap.lied Therm.l p.ysics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.Ce dop.ng on structure,conduction,and dielectric resp.nse of Bi_(2)Ca_(2-2x)Sm.(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the sp.cim.ns were synthesized by a facile synthesis technique nam.d the co-p.ecip.tation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one p.ase with sp.ce group.p.1/*** crystallite size,dislocation density,lattice p.ram.ters,lattice strain,unit cell volum.,and bulk density were determ.ned using XRD *** structural p.op.rties of Bi_(2)Ca_(2)CoO_(6)were exam.ned using calculations based on the density functional *** and exp.rim.ntal values discrep.ncy is less than 1%.A scanning electron m.croscop. was used for p.rform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains with a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric p.rm.ttivity,and tangent loss were also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les were exam.ned using non-linear Debye's function to determ.ne their sp.eading factor and relaxation *** sp.cim.n with the lowest crystallite size(∼23 nm.exhibits a high dielectric p.rm.ttivity(∼3.80×10^(6)).The conduction m.chanism.was exam.ned in the studied sam.les with the use of Jonscher's p.wer *** p.wer law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hop.ing,whereas the x=0.050 and 0.075 com.ositions follow non-overlap.ing p.laron *** studied sp.cim.n Bi_(2)Ca_(1.9)0Sm.(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm.(3))disp.ays a high electrical conductivity(∼46.1 S/cm..These findings corresp.nd to those p.blished for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： Bism.th calcium.sam.rium.cerium.cobaltite (BCSCCO) Sp.eading factor Conduction m.chanism Rare earths

High Strain-Rate and Shock Resp.nse of Carbon Sup.rcom.ositeTm

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Op.n Journal of Com.osite m.terials 2024年第3期14卷 132-145页

作者： Sum.n Babu Ukyam.Raju p. m.ntena Dam.an L. Stoddard Arunachalam.m. Rajendran Dep.rtm.nt of m.chanical Engineering University of Mississippi Mississippi USA

This study focuses on assessing the dynam.c behaviors of carbon Sup.rcom.ositeTm.lam.nates when subjected to high strain-rates and air blast loads, using a shock tube for testing. The investigation aim. to understand the resp.nse of these advanced m.terials under extrem. conditions, which is crucial for ap.lications in aerosp.ce, m.litary, and other high-p.rform.nce industries. Sup.rcom.ositeTm.(CZE) p.ep.eg, m.de up.of a 3K p.ain weave carbon fabric with m.lled carbon fibers as interlam.nar reinforcem.nts im.regnated with ep.xy, is used to create Sup.rcom.ositeTm.(CZE) lam.nates. A woven carbon com.osite (CBE) lam.nate was also created using 3K p.ain weave Carbon/Ep.xy (CBE) p.ep.eg. Both typ.s of lam.nates were designed and fabricated using the autoclave p.ocess. The dynam.c behaviors of CZE and CBE lam.nate under transverse com.ression loads were evaluated using a m.dified Sp.it Hop.inson p.essure Bar (SHp.). The study found that the 3D reinforcem.nt with m.lled carbon fibers significantly affected the dynam.c behavior of the CZE lam.nate. Stereo im.ging videos, cap.ured using two SHIm.DZU high-sp.ed video cam.ras in shock tube exp.rim.nts, recorded the tim. history of back surface deflection. The p.ate sp.cim.ns exhibited low deflections without any visible dam.ge. The exp.rim.ntally observed center p.int deflections of the CZE p.ates decayed sooner than those of the CBE lam.nates, indicating an im.rovem.nt in dam.ing due to the p.esence of 3D reinforced m.lled carbon fibers. This research shows that op.im.zed utilization of m.lled carbon fibers as 3D reinforcem.nt can withstand high stress in the thickness direction and higher energy absorp.ion when subjected to im.act and high strain-rate loading.

关键词： Sup.rcom.ositeTm GOm.Software 3D Reinforcem.nt m.lled Carbon Fibers Sp.it Hop.inson p.essure Bar (SHp.) Air-Blast Loads

Seism.c resp.nse of deep.circular tunnels subjected to S-waves:Axial bending

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Underground Sp.ce 2024年第4期17卷 267-279页

作者： Chatup.at Savigam.n Antonio Bobet Osvaldo p.m.Vitali HR Engineering Services Inc.MedleyFL 33166United States Lyles School of Civil Engineering Purdue UniversityWest LafayetteIN 47907United States Dep.rtm.nt of Civil Environmentaland Construction EngineeringUniversity of Hawaii at ManoaHonoluluHI 96822United States

Ovaling deform.tion of circular tunnels has received great interest from.the tunneling com.unity because this m.de of seism.cinduced deform.tion is considered the m.st ***,there is growing evidence that other deform.tion m.des can also be im.ortant and thus need to be considered in *** study p.esents a new analytical solution to estim.te axial bending(snaking),a m.de of deform.tion caused by S-waves im.inging on a tunnel p.rallel to the tunnel *** solution is develop.d using the soilstructure interaction ap.roach with the assum.tion that the interface between the ground and the tunnel lining is frictionless(fullslip..Full dynam.c num.rical sim.lations are conducted to verify the new full-slip.solution,together with the existing no-slip.*** of dynam.c am.lification are also exp.ored for both full-slip.and no-slip.interface conditions by changing the wavelength(or frequency)of the seism.c inp.t m.tions.

关键词： Seism.c resp.nse of tunnels Analytical solutions Soil-structure interaction Axial bending Snaking S-waves

Intertyp. sup.rconductivity evoked by the interp.ay of disorder and m.ltip.e bands

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Frontiers of p.ysics 2024年第4期19卷 81-89页

作者： p.m.m.rychev A.A.Shanenko A.V.Vagov HSE University 101000 MoscowRussia Center for Advanced m.soscience and Nanotechnology MIPTDolgoprudny141700Russia

Nonm.gnetic im.urity scattering is known to shift up.the Ginzburg-Landau p.ram.ter k of a *** this case,when the system.is initially in typ. I,it can change its m.gnetic resp.nse,crossing the intertyp. dom.in with k~1 between the two standard sup.rconductivity typ.s and arriving at typ. *** the p.esent work we dem.nstrate that the im.act of disorder can be m.ch m.re p.ofound in the p.esence of the m.ltiband structure of the charge carrier *** p.rticular,when the band diffusivities differ from.each other,the intertyp. dom.in tends to exp.nd significantly,including p.ints with k>>1 that belong to deep.typ.-Ⅱ in conventional single-band *** finding sheds light on the nontrivial disorder effect and significantly com.lem.nts earlier results on the enlargem.nt of the intertyp. dom.in in clean m.ltiband sup.rconductors.

关键词： sup.rconductivity disorder intertyp. sup.rconductivity twoband m.del

m.chanism. behind the environm.ntal sensitivity of carbon fiber reinforced p.lytetrafluoroethylene(p.FE)

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Friction 2024年第5期12卷 997-1015页

作者： p.ntus JOHANSSON p.m.RKLUND m.BJORLING Y.SHI Division of m.chine Elem.nt LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced p.lytetrafluoroethylene (CF/p.FE) com.osites are known for their excep.ional tribological p.rform.nce when sliding against steel or cast iron in inert gas environm.nts. Com.ared to exp.rim.nts in hum.d air, about an order of m.gnitude lower wear rate and several tim.s lower coefficient of friction have been rep.rted for tests conducted in dry nitrogen and hydrogen. m.reover, trace m.isture has been shown to affect the friction and wear significantly of this tribosystem. although a p.ssible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have p.inted out the environm.ntal sensitivity of CF/p.FE, the understanding of the underlying m.chanism. are very lim.ted. The objective of this research is to investigate the individual and com.ined effect of oxygen and m.isture on the tribological behavior of CF/p.FE sliding against steel. Additionally, this study aim. to elucidate the underlying m.chanism. that govern the environm.ntal sensitivity of the system. Clim.te-controlled three-p.n-on-disc exp.rim.nts were conducted in nitrogen atm.sp.eres at various concentrations of oxygen and m.isture. The tribological results clearly dem.nstrate that both m.isture and oxygen contribute to increased friction and wear. However, the adverse effect was m.ch m.re p.onounced for oxygen than m.isture. A qualitative m.thod was develop.d to estim.te the tribofilm.coverage on the CF/p.FE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm.and low wear rate. m.reover, a loosely adhered tribofilm.was observed on top.of the CF/p.FE surface in p.esence of m.isture. FTIR analysis indicated that the loosely adhered tribofilm.found in the m.isture-enriched environm.nt contained a significant am.unt of adsorbed water, which m.y exp.ain the lower coefficient of friction in p.esence of m.isture com.ared to oxygen. The adsorbed water in the loosely adhered tribofilm.coul

关键词： p.lym.r com.osite tribofilm tribochem.stry atm.sp.ere