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Long-ter. monitor.ng of cycles in Clethr.onomys r.tilus in the Yukon bor.al for.st

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Integr.tive Zoology 2024年第1期19卷 27-36页

作者： Char.es j.Kr.BS Alice j.KENNEY B.Scott gILBEr. r.dy BOONSTr. Depar.ment of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada r.newable r.sour.es Management Pr.gr.m Yukon UniversityWhitehorseYukonCanada Depar.ment of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada

Baseline studies of small r.dent populations in undistur.ed ecosystems ar. *** r.por. her. 50 year. of mon-itor.ng and exper.mentation in Yukon of a dominant r.dent species in the Nor.h Amer.can bor.al for.st,the r.d-backed vole Clethr.onomys *** voles br.ed in summer.weigh 20–25 g,and r.ach a maximum density of 20 to 25 per.*** populations have shown consistent 3–4-year.cycles for.the last 50 year. with the only change being that peak densities aver.ged 8/ha until 2000 and 18/ha since that *** the last 25 year.,we have measur.d food r.sour.es,pr.dator.number.,and winter.weather.and for.1-year.social inter.ctions,to estimate their.contr.bution to changes in the r.te of summer.incr.ase and the r.te of over.inter.*** these potential limiting factor. could contr.bute to changes in density,and we measur.d their.r.lative contr.butions statistically with multiple *** r.te of winter.decline in density was r.lated to both food supply and winter.*** r.te of summer.incr.ase was r.lated to summer.ber.y cr.ps and white spr.ce cone *** measur. of pr.dator.number. was r.lated to winter.or.summer.changes in vole *** was a lar.e signal of climate change effects in these *** is no density dependence in summer.population gr.wth and only a weak one in winter.population *** of our.r.sults pr.vide a clear.under.tanding of what gener.tes 3–4-year.cycles in these voles,and the maj.r.missing piece may be an under.tanding of social inter.ctions at high density.

关键词： bor.al for.st climate change density dependence population cycles pr.dation winter.sever.ty

Bianchi Type-Ⅲ Cosmological Models with gr.vitational Constant g and the Cosmological Constant A

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Chinese Physics Letter. 2007年第12期24卷 3325-3327页

作者： j. P. Singh r. K. Tiwar. Pr.tibha Shukla Depar.ment of Mathematical Sciences A.P.S. University Rewa (MP) India Depar.ment of Mathematics Govt. Model Science College Rewa (MP) India

Einstein field equations with var.able gr.vitational and cosmological constants ar. consider.d in the pr.sence of per.ect fluid for.the Bianchi type-Ⅲ univer.e by assuming conser.ation law for.the ener.y-momentum tensor. Exact solutions of the field equations ar. obtained by using the scalar.of expansion pr.por.ional to the shear.scalar.θ∝σ, which leads to a r.lation between metr.c potential B = Cn, wher. n is a constant. The cor.esponding physical inter.r.tation of the cosmological solutions ar. also discussed.

关键词： Cosmological Models Cosmological Constant

Or.anochlor.des Mediate Oxidation r.actions Induced by Low Dose Ionizing r.diation

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CCS Chemistr. 2024年第7期6卷 1712-1720页

作者： j.ncheng Liu Tobias g.Br.vé Bing Xu Peter.Leon Hagedoor. Antonia g.Denkova r.enk Eelkema Depar.ment of r.diation Science and Technology Delft University of Technology2629 JB Delft Depar.ment of Chemical Engineer.ng Delft University of Technology2629 HZ Delft Depar.ment of Biotechnology Delft University of Technology2629 HZ Delft

The contr.lled r.lease of dr.gs using local ionizing r.diation pr.sents a pr.mising appr.ach for.tar.eted cancer.tr.atment,par.icular.y when applied in concur.ent *** these appr.aches,r.diation-gener.ted r.active species often play an impor.ant ***,the r.active species that can be used to tr.gger.r.lease have low yield and lack ***,we demonstr.te the gener.tion of highly oxidative species when aqueous solutions containing low concentr.tions of or.anochlor.des(such as chlor.for.)ar. ir.adiated with ionizing r.diation at ther.peutically r.levant *** r.active species wer. identified as per.xyl r.dicals,which for.ed in a r.action cascade between or.anochlor.des and aqueous *** employed stilbene-based pr.bes to investigate the oxidation pr.cess,showing double bond oxidation and *** tr.nslate this r.activity into a r.diation-sensitive mater.al,we synthesized a micelle-for.ing amphiphilic block copolymer.that has stilbene as the linker.between two *** exposur. to ionizing r.diation,the oxidation of stilbene led to the cleavage of the polymer.which induces the dissociation of the block-copolymer.micelles and the r.lease of loaded dr.gs.

关键词： dr.g deliver. micelles r.diation chemistr. r.active oxygen species ionizing r.diation r.action mechanisms

Analysis of Mobile and Inter.et Networ. Cover.ge: Pr.pagation of Electr.magnetic Waves and Concept of Digital Divide in Bur.ndi

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Open j.ur.al of Antennas and Pr.pagation 2024年第1期12卷 1-18页

作者： Apollinair. Bigir.mana j.r.mie Ndikumagenge Sami Tabbane r.meo Nibitanga Hassan Kibeya Center.for.r.sear.h in Infr.str.ctur. Environment and Technology (CRIET) Doctoral School of the University of Burundi Bujumbura Burundi Center.for.r.sear.h in Infr.str.ctur. Environment and Technology (CRIET) University of Burundi Bujumbura Burundi Higher.School of Communications of Tunis Technological City of Communications Ariana Tunisia Faculty of Engineer.ng Sciences Universit du Burundi Bujumbura Burundi

Mobile and Inter.et networ. cover.ge plays an impor.ant r.le in digital tr.nsfor.ation and the exploitation of new ser.ices. The evolution of mobile networ.s fr.m the fir.t gener.tion (1g) to the 5th gener.tion is still a long pr.cess. 2g networ.s have developed the messaging ser.ice, which complements the alr.ady oper.tional voice ser.ice. 2g technology has r.pidly pr.gr.ssed to the thir. gener.tion (3g), incor.or.ting multimedia data tr.nsmission techniques. It then pr.gr.ssed to four.h gener.tion (4g) and LTE (Long Ter. Evolution), incr.asing the tr.nsmission speed to impr.ve 3g. Cur.ently, developed countr.es have alr.ady moved to 5g. In developing countr.es, including Bur.ndi, a member.of the East Afr.can Community (ECA) wher. mor. than 80% ar. connected to 2g technologies, 40% ar. connected to the 3g networ. and 25% to the 4g networ. and ar. not yet connected to the 5g networ. and then still a pr.cess. The obj.ctive of this ar.icle is to analyze the cover.ge of 2g, 3g and 4g networ.s in Bur.ndi. This analysis will make it possible to identify possible deficits in or.er.to r.duce the digital divide between connected ur.an ar.as and r.mote r.r.l ar.as. Fur.her.or., this analysis will dr.w the attention of decision-maker. to the need to deploy networ.s and cover.ge to allow the population to access mobile and Inter.et ser.ices and thus enable the digitalization of the population. Finally, this ar.icle shows the level of cover.ge, the digital divide and an over.iew of the deployment of base stations (BTS) thr.ughout the countr. to pr.mote the tr.nsfor.ation and digital inclusion of ser.ices.

关键词： Cover.ge of Mobile Networ.s and Inter.et Digital Divide r.r.l and Isolated Ar.as Antenna Connectivity and Digital Inclusion

Statistical evaluation of 571 gaAs quantum point contact tr.nsistor. showing the 0.7 anomaly in quantized conductance using cr.ogenic on-chip multiplexing

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Chip 2024年第3期3卷 21-28页

作者： Pengcheng Ma Kaveh Delfanazar. r.uben K.Puddy j.ahui Li Moda Cao Teng Yi j.nathan P.gr.ffiths Har.ey E.Beer. David A.r.tchie Michael j.Kelly Char.es g.Smith Cavendish Labor.tor. Department of PhysicsUniversity of CambridgeCambridge CB30HEUK j.mes Watt School of Engineer.ng University of GlasgowGlasgow G128QQUK Electr.cal Engineer.ng Division University of CambridgeCambridge CB30FAUK

Themass pr.duction and the pr.ctical number.of cr.ogenic quantum devices pr.ducible in a single chip ar. limited to the number.of electr.cal contact pads and wir.ng of the cr.ostat or.dilution *** is,ther.for.,beneficial to contr.st themeasur.ments of hundr.ds of devices fabr.cated in a single chip in one cooldown pr.cess to pr.mote the scalability,integr.bility,r.liability,and r.pr.ducibility of quantum devices and to save evaluation time,cost and ***,we used a cr.ogenic on-chip multiplexer.ar.hitectur. and investigated the statistics of the 0.7 anomaly obser.ed on the fir.t thr.e plateaus of the quantized conductance of semiconductor.quantum point contact(QPC)*** single chips contain 256 split gate field-effect QPC tr.nsistor.(QFET)each,with two 16-br.nch multiplexed sour.e-dr.in and gate pads,allowing individual tr.nsistor. to be selected,addr.ssed and contr.lled thr.ugh an electr.static gate voltage pr.cess.A total of 1280 quantum tr.nsistor. with nano-scale dimensions ar. patter.ed in 5 differ.nt chips of gaAs *** the measur.ments of 571 functioning QFETs taken at temper.tur.s T[1.4 K and T[40 mK,it is found that the spontaneous polar.sation model and Kondo effect do not fit our.***,some of the featur.s in our.data lar.ely agr.ed with van Hove model with shor.-r.nge *** appr.ach pr.vides fur.her.insight into the quantum mechanical pr.per.ies and micr.scopic or.gin of the 0.7 anomaly in QFETs,paving the way for.the development of semiconducting quantum cir.uits and integr.ted cr.ogenic electr.nics,for.scalable quantum logic contr.l,r.adout,synthesis,and pr.cessing applications.

关键词： Cr.ogenic chip Cr.ogenic quantum multiplexer Semi-conductor.quantum integr.ted cir.uit Quantumﬁeld effect tr.nsistor. Quantum point contacts Chip-scale cr.ogenic electr.nics

Per.or.ance and calibr.tion of quar./gluon-j.t tagger. using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAS detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： g. Aad B. Abbott K. Abeling N.j. Abicht S.H. Abidi A. Aboulhor.a H. Abr.mowicz H. Abr.u Y. Abulaiti B.S. Achar.a C. Adam Bour.ar.os L. Adamczyk S.V. Addepalli M.j. Addison j. Adelman A. Adiguzel T. Adye A.A. Affolder.Y. Afik M.N. Agar.s j. Agar.ala A. Aggar.al C. Agheor.hiesei A. Ahmad F. Ahmadov W.S. Ahmed S. Ahuj. X. Ai g. Aielli A. Aikot M. Ait Tamlihat B. Aitbenchikh I. Aizenber. M. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar.K. Al Khour. g.L. Alber.hi j. Alber. P. Albicocco g.L. Albouy S. Alder.eir.ldt M. Aleksa I.N. Aleksandr.v C. Alexa T. Alexopoulos F. Alfonsi M. Algr.n M. Alhr.ob B. Ali H.M.j. Ali S. Ali S.W. Alibocus M. Aliev g. Alimonti W. Alkakhi C. Allair. B.M.M. Allbr.oke j.F. Allen C.A. Allendes Flor.s P.P. Allpor. A. Aloisio F. Alonso C. Alpigiani M. Alvar.z Estevez A. Alvar.z Fer.andez M. Alves Car.oso M.g. Alviggi M. Aly Y. Amar.l Coutinho A. Ambler.C. Amelung M. Amer. C.g. Ames D. Amidei S.P. Amor.Dos Santos K.r. Amos V. Ananiev C. Anastopoulos T. Andeen j.K. Ander. S.Y. Andr.an A. Andr.azza S. Angelidakis A. Anger.mi A.V. Anisenkov A. Annovi C. Antel M.T. Anthony E. Antipov M. Antonelli F. Anulli M. Aoki T. Aoki j.A. Apar.si Pozo M.A. Apar. L. Aper.o Bella C. Appelt A. Apyan N. Ar.nzabal S.j. Ar.iol Val C. Ar.angeletti A.T.H. Ar.e E. Ar.na j.F. Ar.uin S. Ar.yr.poulos j.-H. Ar.ing O. Ar.aez H. Ar.old g. Ar.oni H. Asada K. Asai S. Asai N.A. Asbah j. Assahsah K. Assamagan r. Astalos S. Atashi r.j. Atkin M. Atkinson H. Atmani P.A. Atmasiddha K. Augsten S. Aur.cchio A.D. Aur.ol V.A. Austr.p g. Avolio K. Axiotis g. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia M. Bahmani A.j. Bailey V.r. Bailey j.T. Baines L. Baines O.K. Baker.E. Bakos D. Bakshi gupta V. Balakr.shnan r. Balasubr.manian E.M. Baldin P. Balek E. Ballabene F. Balli L.M. Baltes W.K. Balunas j. Balz E. Banas M. Bandier.monte A. Bandyopadhyay S. Bansal L. Bar.k M. Bar.kat E.L. Bar.er.o D. Bar.er.s M. Bar.er. M.Z. Bar.l K.N. Bar.nds T. Bar.llar. M-S. Bar.sits T. Bar.low P. Bar.n D.A. Bar.n Mo The ATLAS Collabor.tion

The identification of j.ts or.ginating fr.m quar.s and gluons,often r.fer.ed to as quar./gluon tagging,plays an impor.ant r.le in var.ous analyses per.or.ed at the Lar.e Hadr.n Collider.as Standar. Model measur.ments and sear.hes for.new par.icles decaying to quar.s often r.ly on suppr.ssing a lar.e gluon-induced *** paper.descr.bes the measur.ment of the efficiencies of quar./gluon tagger. developed within the ATLAS Collabor.tion,using √s=13 TeV pr.ton–pr.ton collision data with an integr.ted luminosity of 140 fb^(-1) collected by the ATLAS *** tagger. with high per.or.ances in r.j.cting j.ts fr.m gluon over.j.ts fr.m quar.s ar. studied:one tagger.is based on r.quir.ments on the number.of inner.detector.tr.cks associated with the j.t,and the other.combines sever.l j.t substr.ctur. obser.ables using a boosted decision tr.e.A method is established to deter.ine the quar./gluon fr.ction in data,by using quar./gluon-enr.ched subsamples defined by the j.t *** in tagging efficiency between data and simulation ar. pr.vided for.j.ts with tr.nsver.e momentum between 500 geV and 2 TeV and for.multiple tagger.wor.ing points.

关键词： ATLAS j.T QUAr. gLUON TAggINg

Metamater.al-based gr.phene ther.al emitter

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Nano r.sear.h 2018年第7期11卷 3567-3573页

作者： Cheng Shi Nathan H. Mahlmeister.Isaac j. Luxmoor. geoffr.y r. Nash College of Engineer.ng Mathematics and PhysicaI Sciences University of Exeter Exeter EX4 4QF UK

A ther.al emitter.composed of a fr.quency-selective sur.ace metamater.al layer.and a hexagonal bor.n nitr.de-encapsulated gr.phene filament is demonstr.ted. The br.adband ther.al emission of the metamater.al （consisting of r.ng r.sonator.） was tailor.d into two discr.te bands, and the measur.d r.flection and emission spectr. agr.ed well with the simulation r.sults. The high modulation fr.quencies that can be obtained in these devices, coupled with their.oper.tion in air. confir. their.feasibility for.use in applications such as gas sensing.

关键词： gr.phene hexagonal bor.n nitr.de ther.al emitter infr.r.d metamater.al

Scales of snow depth var.ability in high elevation r.ngeland sagebr.sh

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Fr.ntier. of Ear.h Science 2017年第3期11卷 469-481页

作者： Molly E. TEDESChe Steven r. FASSNACHT Paul j. MEIMAN Water.hed Science Department of Ecosystem Science and Sustainability Colorado State University Fort Collins CO 80523-1476 USA Intemational Ar.tic r.sear.h Center Water & Environmental Research Center Institute of Northern Engineering University of Alaska Fairbanks Fairbanks AK 99775 USA Cooper.tive Institute for.r.sear.h in the Atmospher. Fort Collins CO 80523-1375 USA Natur.l r.sour.es Ecology Labor.tor. Fort Collins CO 80523-1499 USA Abt. Kar.ogr.phie GIS & Femerkundung Geographisches Institut Georg-August-Universitat Gottingen 37077 Gottingen Germany r.ngeland Ecosystem Science Department of Forest and Rangeland Stewardship Colorado State University Fort Collins CO 80523 USA

In high elevation semi-ar.d r.ngelands, sage- br.sh and other.shr.bs can affect tr.nspor. and deposition of wind-blown snow, enabling the for.ation of snowdr.fts. Datasets fr.m thr.e field exper.ments wer. used to investigate the scales of spatial var.ability of snow depth ar.und big mountain sagebr.sh （Ar.emisia tr.dentata Nutt.） at a high elevation plateau r.ngeland in Nor.h Par., Color.do, dur.ng the winter. of 2002, 2003, and 2008. Data wer. collected at multiple r.solutions （0.05 to 25 m） and extents （2 to 1000 m）. Finer.scale data wer. collected specifically for.this study to examine the cor.elation between snow depth; sagebr.sh micr.topogr.- phy, the gr.und sur.ace, and the snow sur.ace, as well as the tempor.l consistency of snow depth patter.s. Var.o- gr.ms wer. used to identify the spatial str.ctur. and the Mor.n＇s I statistic was used to deter.ine the spatial cor.elation. r.sults show some tempor.l consistency in snow depth at sever.l scales. Plot scale snow depth var.ability is par.ly a function of the natur. of individual shr.bs, as ther. is some cor.elation between the spatial str.ctur. of snow depth and sagebr.sh, as well as between the gr.und and snow depth. The optimal sampling r.solution appear. to be 25-cm, but over.a lar.e ar.a, this would r.quir. a multitude of samples, and thus a r.ndom str.tified appr.ach is r.commended with a fine measur.ment r.solution of 5-cm.

关键词： snow hydr.logy high elevation r.ngelands,spatial statistics var.ogr.ms snow pack spatial var.ability,snow dr.fts

Factor. Associated with Over.eight among Wor.er. of the Ministr. of Labor.and Public Ser.ice in Benin in 2023

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Open j.ur.al of Inter.al Medicine 2024年第3期14卷 299-318页

作者： Lucile T. S. Bedie Toïhen gér.ud Padonou Char.es j.r.me Sossa Bayédj. Evr.r. Koutchor. Sègnon Eur.dice Elvir. Dj.ssou Coovi Nonwanou Ignace Tokpanoude Badir.u Aguemon Ministr. of Labor.and Public Ser.ice Cotonou Benin Faculty of health Sciences (FSS) University of Abomey-Calavi (UAC) Cotonou Benin health Pr.motion Depar.ment Regional Institute of Public Health Ouidah Benin

Intr.duction: The pr.blem of excess weight is pandemic and affects the maj.r.ty of nations, r.gar.less of their.level of development. However. the pr.valence of over.eight among wor.er. in Benin is ver. poor.y documented. To fill this gap, the pr.sent study aimed to deter.ine the pr.valence and factor. associated with over.eight among wor.er. of the Ministr. of Labor.and Public Ser.ice (MTFP) in 2023 in Benin. Mater.als and Methods: This is a descr.ptive cr.ss-sectional study with analytical pur.oses car.ied out fr.m August 16 to December.17, 2023, among MINISTr. OF LABOr.AND PUBLIC SEr.ICE staff. The var.ables studied wer. over.eight, sociodemogr.phic, occupational and dietar. char.cter.stics, lifestyle, anthr.pometr.c factor. and family histor. of obesity. An exhaustive r.cr.itment of wor.er. meeting our.inclusion cr.ter.a and a questionnair. sur.ey was car.ied out. Data wer. analyzed using r.4.0.4 softwar.. A bivar.ate analysis followed by a multivar.able analysis made it possible to identify the factor. associated with over.eight at the p r.sults: In total, 379 wor.er. wer. included in our.study. The aver.ge age of the sur.eyed wor.er. was 44.86 year. ± 7.67 year., with 202 (53.30%) wor.er. at least 45 year. old. Men pr.dominated with a number.of 228 (60.16%). The pr.valence of over.eight was 63.32% (95% CI: [58.23 - 68.15]) and the associated factor. after.multivar.ate analysis wer.: female sex (Or. = 4.00;95% CI [2.11 - 7.76];p Conclusion: The pr.valence of over.eight is high among ministr. of labor.and public ser.ice wor.er.. Education and awar.ness in the pr.fessional envir.nment on the pr.vention and management of r.sk factor. ar. essential for.a long-ter. impact on a notable r.gr.ssion of this public health phenomenon.

关键词： Over.eight Associated Factor. Wor.er.-Benin