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Drought events influence nutrient canopy exchanges and green leaf partitioning 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.Turpault 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 expected in the com.ng decades in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in trees.One possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced leaves.However,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly docum.nted.An experim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence period.The aim.was to identify potential nutritional consequences of droughts for trees.m.nitoring nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption 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 potassium.K)partitioning to resorption(i.***.resorption efficiency),thus reducing the K reserve in trees for the next growing season.This result suggests that with the increased drought frequency and intensity expected for the com.ng decades,there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study site.Reduced foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also observed.In addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree nutrition.The calcium.Ca)negative resorption decreased,with no apparent consequence in our study site.Our results show that nutrient exchanges in the canopy and the partitioning of the green leaf pool can be m.dified by drought events,and m.y

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

Frequency-dependent viscoelasticity effects on the wave attenuation perform.nce of m.lti-layered periodic foundations

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.m.Hm.ODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of m.chanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are num.rically exam.ned for their responses to longitudinal and transverse m.des in the tim. and frequency dom.ins.Three different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,com.rising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber m.terials,respectively,are taken into account.Also,the viscoelasticity behavior of the rubber is m.deled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss factor.Following the extraction of the com.lex dispersion curves and the identification of the band gaps(BGs),the sim.lations of wave transm.ssion in the tim. and frequency dom.ins are perform.d using the COm.OL software.Subsequent param.tric studies evaluate the effects of the rubber viscoelasticity m.dels on the dispersion curves and the wave transm.ssion for the longitudinal and transverse m.des.The results show that considering the rubber viscoelasticity enhances the wave attenuation perform.nce.m.reover,the transverse-m.de dam.ing is m.re sensitive to the viscoelasticity m.del than its longitudinal counterpart.The 6-layer unit-cell LPF exhibits the lowest BG,ranging from.4.8 Hz to 6.5 Hz.

关键词： layered m.tam.terial periodic foundation com.lex dispersion curve wave transm.ssion diagram

Concentration of Copper, Zinc, Lead, Cadm.um. and Nickel in the Incinerator Bottom.Ash in Five County Hospitals in Kenya

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j.urnal of Geoscience and Environm.nt Protection 2024年第6期12卷 90-114页

作者： m.riithi j. Githinj. Paul m. Nj.gu Zipporah Nganga m.ham.d Karam. Institute of Tropical m.dicine and Infectious Diseases (ITROm.D) Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya Institute of Energy and Environm.ntal Technology Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya Academ.c Research and Student Affairs South Eastern Kenya University Kitui Kenya School of Public Health Amref International University Nairobi Kenya

Healthcare wastes contain potentially harm.ul m.croorganism., inorganic and organic com.ounds that pose a risk to hum.n health and the environm.nt. Incineration is a com.on m.thod em.loyed in healthcare waste m.nagem.nt to reduce volum., quantity, toxicity as well as elim.nation of m.croorganism.. However, som. of the substances rem.in unchanged during incineration and becom. part of bottom.ash, such as heavy m.tals and persistent organic pollutants. m.nitoring of pollution by heavy m.tals is im.ortant since their concentrations in the environm.nt affect public health. The goal of this study was to determ.ne the levels of Copper (Cu), Zinc (Zn) Lead (Pb), Cadm.um.(Cd) and Nickel (Ni) in the incinerator bottom.ash in five selected County hospitals in Kenya. Bottom.ash sam.les were collected over a period of six m.nths. Sam.le preparation and treatm.nt were done using standard m.thods. Analysis of the heavy m.tals were done using atom.c absorption spectrophotom.ter, m.del AA-6200. One-Way Analysis of Variance (ANOVA) was perform.d to determ.ne whether there were significant differences on the m.an levels of Cu, Zn, Pd, Cd and Ni in incinerator bottom.ash from.the five sam.ling locations. A post-hoc Tukey’s Test (HSD) was used to determ.ne if there were significant differences between and within sam.les. The significant differences were accepted at p ≤ 0.05. To standardize the results, overall m.an of each m.tal from.each site was calculated. The m.tal m.an concentration values were com.ared with existing perm.ssible levels set by the WHO. The concentrations (m./kg) were in the range of 102.27 - 192.53 for Cu, Zn (131.68 - 2840.85), Pb (41.06 - 303.96), Cd (1.92 - 20.49) whereas Ni was (13.83 - 38.27) with a m.an of 150.76 ± 77.88 for Copper, 131.66 ± 1598.95 for Zinc, 234.60 ± 262.76 for Lead, 12.256 ± 10.86 for Cadm.um.and 29.45 ± 18.24 for Nickel across the five sam.ling locations. There were significant differences between levels determ.ned by one-way ANOVA of Zn (F (4, 25) = 6.893, p = 0.001, p ≤ 0.05) and Cd (

关键词： Healthcare Waste Disposal Public Health Environm.nt Incineration Heavy m.tals Bottom.Ash

Otolaryngology residency program.factors associated with fem.le resident representation

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World j.urnal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 7-11页

作者： j.lia E.Canick j.m.s C.Cam.bell Charles R.Woodard Lars j.Grim. Alissa m.Collins Duke University School of m.dicine DurhamNorth CarolinaUSA Departm.nt of Head and Neck Surgery&Com.unication Sciences Duke University School of MedicineDurhamNorth CarolinaUSA Departm.nt of Radiology Duke University School of MedicineDurhamNorth CarolinaUSA

Obj.ctive:Fem.le representation in the field of otolaryngology is lacking.Residency is the first point at which m.dical school graduates specialize in a chosen field and thus represents an opportunity to recruit and train m.re fem.le otolaryngologists.This study sought to identify program.factors associated with greater fem.le representation am.ng resident physicians.m.thods:Departm.ntal websites of all 124 otolaryngology residency program. in the United States and Puerto Rico were exam.ned for a list of residents.For program. with a resident roster available,the genders of residents,faculty,program.directors,and chairpersons were recorded.Location and city population for each program.was also recorded,as was fem.le resident representation.Program. were com.ared using Pearson Chi‐squared univariate tests.Results:1,632 residents and 2,605 faculty were included in the analysis of 109 program..The m.dian fem.le resident representation was 40%.Program. with larger faculty sizes,m.re fem.le faculty,and urban location were associated with an above‐m.dian fem.le resident representation.Program. with a larger residency cohort approached significance regarding above‐m.dian fem.le resident representation.Higher fem.le faculty representation,program.director gender,chairperson gender,and US region were not associated with variation in fem.le resident representation.Conclusions:Greater fem.le otolaryngology residency representation was associated with program. having an urban location and greater num.ers of fem.le and total faculty.It was also likely that a larger resident cohort size m.y affect fem.le resident representation.The proportions of fem.le faculty,program.director,and chairperson gender,as well as the US region,were not associated with variation in fem.le resident gender representation.

关键词： gender program.director recruitm.nt residency training

Lattice Boltzm.nn m.thod form.lation for sim.lation of therm.l radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determ.nation

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Applied m.them.tics and m.chanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.NEm.TI m.SEFID A.KARIm.POUR A.j.CHAm.HA Faculty of m.chanical Engineering Yazd UniversityYazd ***Iran Departm.nt of m.chanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The sim.ltaneous investigation on the param.ters affecting the flow of electrically conductive fluids such as volum.tric radiation,heat absorption,heat generation,and m.gnetic field(m.)is very vital due to its existence in various sectors of industry and engineering.The present research focuses on m.them.tical m.deling to sim.late the cooling of a hot com.onent through power-law(PL)nanofluid convection flow.The tem.erature reduction of the hot com.onent inside a two-dim.nsional(2D)inclined cham.er with two different cold wall shapes is evaluated.The form.lation of the problem.is derived with the lattice Boltzm.nn m.thod(LBm.by code writing via the FORTRAN language.The variables such as the radiation param.ter(0–1),the Hartm.nn num.er(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh num.er(103–105),the im.osed m. angle(0°–90°),the cham.er inclination angle(−90°–90°),and the cavity cold wall shape(sm.oth and curved)are investigated.The findings indicate that the presence of radiation increases the m.an Nusselt num.er value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,respectively.In m.st cases,the presence of nanoparticles im.roves the heat transfer(HT)rate,especially in the cases where therm.l conduction dom.nates convection.There is the lowest cooling perform.nce index and m. effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this num.rical research.

关键词： therm.l perform.nce analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid m.gnetohydrodynam.cs natural convection volum.tric radiation inclined cavity

Utilization of Logistical Regression to the m.dified Sine-Gordon m.del in the m.T Experim.nt

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Open j.urnal of m.delling and Sim.lation 2024年第2期12卷 43-58页

作者： Nizar j. Alkhateeb Ham.ed K. Ebraheem.Em.n m. Al-Otaibi Departm.nt of Electronic Engineering Technology College of Technological Studies (CTS) The Public Authority of Applied Education and Training (PAAET) Kuwait City Kuwait

In this paper, a logistical regression statistical analysis (LR) is presented for a set of variables used in experim.ntal m.asurem.nts in reversed field pinch (RFP) m.chines, com.only known as “slinky m.de” (Sm., observed to travel around the torus in m.dison Sym.etric Torus (m.T). The LR analysis is used to utilize the m.dified Sine-Gordon dynam.c equation m.del to predict with high confidence whether the slinky m.de will lock or not lock when com.ared to the experim.ntally m.asured m.tion of the slinky m.de. It is observed that under certain conditions, the slinky m.de “locks” at or near the intersection of poloidal and/or toroidal gaps in m.T. However, locked m.de cease to travel around the torus;while unlocked m.de keeps traveling without a change in the energy, m.king it hard to determ.ne an exact set of conditions to predict locking/unlocking behaviour. The significant key m.del param.ters determ.ned by LR analysis are shown to im.rove the Sine-Gordon m.del’s ability to determ.ne the locking/unlocking of m.gnetohydrodyam.c (m.D) m.des. The LR analysis of m.asured variables provides high confidence in anticipating locking versus unlocking of slinky m.de proven by relational com.arisons between sim.lations and the experim.ntally m.asured m.tion of the slinky m.de in m.T.

关键词： m.dison Sym.etric Torus (m.T) m.gnetohydrodyam.c (m.D) Sine-Gordon Toroidal Dynam.c m.delling Reversed Field Pinch (RFP) Logistical Regression

Im.act of device resistances in the perform.nce of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía m.López Baptista K.Watanabe T.Taniguchi E.Diez j.E.Velázquez-Pérez Y.m.m.ziani j.m.Caridad j.A.Delgado-Notario Departm.nt of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en Luz y m.teria Estructurada(LUm.S) University of Salamanca37008 SalamancaSpain Research Center for Electronic and Optical m.terials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for m.terials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFETs)have dem.nstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and high-sensitivity.Such features are essential to enable em.rging THz applications,including 6G wireless com.unications,quantum.inform.tion,bioim.ging and security.However,the overall perform.nce of these photodetectors m.y be utterly com.rom.sed by the im.act of internal resistances presented in the device,so-called access or parasitic resistances.In this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-m.bility dual-gate GFET detectors.Such dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of m.gnitude and consequently dem.nstrate an im.roved responsivity and noise-equivalent-power values of the photodetector,respectively.Our results can be well understood by a series resistance m.del,as shown by the excellent agreem.nt found between the experim.ntal data and theoretical calculations.These findings are therefore relevant to understand and im.rove the overall perform.nce of existing high-m.bility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasm.nic

Prim.ry and Secondary m.croplastic and Nanoplastic Regulations: Perspectives on Water Industry Im.acts

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j.urnal of Environm.ntal Protection 2024年第6期15卷 697-715页

作者： Shirin Estahbanati Giridhar Upadhyaya m.rtha j. m. Wells Katherine Y. Bell Brown and Caldwell New York NY USA Brown and Caldwell Irvine CA USA EnviroChem.Services Cookeville TN USA Brown and Caldwell Nashville TN USA

Plastic pollution, both prim.ry and secondary, is an environm.ntal challenge, prom.ting regulatory actions at global and regional levels. With increasing research about the im.acts of m.cro- and nanoplastics on ecosystem. and hum.n health, governm.nts worldwide have undertaken efforts to address this issue. The global com.unity has advanced regulatory efforts that have led to the im.lem.ntation of national laws or regulations in num.rous countries. These m.asures ban or restrict the use of prim.ry and secondary m.croplastics and nanoplastics. An overview of global and European regulatory fram.works is presented to provide context for the United States (US). In the endeavor to docum.nt plastics regulation developm.nt in the US, a description of regulatory agencies and their roles in advancing policy and rules as well as future direction and areas for im.rovem.nt in regulating plastics are introduced. A discussion of what em.rging regulations m.an to utilities and industries is also provided along with a com.arison of regulatory fram.works.

关键词： m.croplastic Regulation Environm.ntal Governance Plastic Pollution m.tigation Regulatory Fram.work

Background rem.val from.global auroral im.ges:Data-driven dayglow m.deling

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Earth and Planetary Physics 2024年第1期8卷 247-257页

作者： A.Ohm. m.m.delaire K.m.Laundal j.P.Reistad S.m.Hatch S.Gasparini S.j.Walker Birkeland Centre for Space Science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global im.ges of auroras obtained by cam.ras on spacecraft are a key tool for studying the near-Earth environm.nt.However,the cam.ras are sensitive not only to auroral em.ssions produced by precipitating particles,but also to dayglow em.ssions produced by photoelectrons induced by sunlight.Nightglow em.ssions and scattered sunlight can contribute to the background signal.To fully utilize such im.ges in space science,background contam.nation m.st be rem.ved to isolate the auroral signal.Here we outline a data-driven approach to m.deling the background intensity in m.ltiple im.ges by form.lating linear inverse problem. based on B-splines and spherical harm.nics.The approach is robust,flexible,and iteratively deselects outliers,such as auroral em.ssions.The final m.del is sm.oth across the term.nator and accounts for slow tem.oral variations and large-scale asym.etries in the dayglow.We dem.nstrate the m.del by using the three far ultraviolet cam.ras on the Im.ger for m.gnetopause-to-Aurora Global Exploration(Im.GE)m.ssion.The m.thod can be applied to historical m.ssions and is relevant for upcom.ng m.ssions,such as the Solar wind m.gnetosphere Ionosphere Link Explorer(Sm.LE)m.ssion.

关键词： aurora dayglow m.deling global auroral im.ges far ultraviolet im.ges dayglow rem.val