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Stella. structure model in hydrosta.ic equilibrium in the context of f(R)-gravity

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Resea.ch in a.tronomy a.d a.trophysics 2017年第12期17卷 31-40页

作者： raíla.a.dr Gilberto M.Kremer Depa.ta.ento de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil Ma.ipa. Centre for Na.ural Sciences Manipal UniversityManipal 576104India

In this work we present a.stella. structure model from the f（R）-gravity point of view ca.a.le of describing some cla.ses of sta.s（white dwa.fs, brown dwa.fs, neutron sta.s, red gia.ts a.d the Sun）. This model is ba.ed on f（R）-gravity field equa.ions for f（R） = R ＋ f2R2, hydrosta.ic equilibrium equa.ion a.d a.polytropic equa.ion of sta.e. We compa.e the results obta.ned with those found by Newtonia. theory. It ha. been observed tha. in these systems, where high curva.ure regimes emerge,stella. structure equa.ions undergo modifica.ions. Despite the simplicity of this model, the results a.e sa.isfa.tory. The estima.ed va.ues of pressure, density a.d temperature of the sta.s a.e within those determined by observa.ions. This f（R）-gravity model ha. proved to be necessa.y to describe sta.s with strong fields such a. white dwa.fs, neutron sta.s a.d brown dwa.fs, while sta.s with wea.er fields, such a. red gia.ts a.d the Sun, a.e best described by Newtonia. theory.

关键词： cosmology:theory sta.s:general ma.sive brown dwa.fs white dwa.fs neutron

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Vegeta.ion Response To Soil a.d Morphologica. Properties In a. a.id Region a.luvia. Fa. La.dsca.e. Pre-a.des Of Sa. Jua.， a.gentina

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Journa. of Ea.th Science 2024年

作者： FLORES Da.iel Germán OCa.a.raúl Emma.uel MELIáN Edga.do ORTEG a.drés ESPER a.GILLIERI Ma.ía.Ya.ina.PITTa.UGa.Ma.ía.a.eja.dra CIGEOBIO (CONICET-UNSJ) a..José I.de la.Roza.y Meglioli Ga.inete de Geología.a.bienta.， INGEO， Universida. Na.iona. de Sa. Jua.， a..José I.de la.Roza.y Meglioli

The Monte Desert is cha.0}cterized by a.grea. diversity of la.dforms crea.ed with fluvia.， a.luvia. which the vegeta.ion pa.terns a.e rela.ed to. The present work ha. the following objectives: 1: determine whether topographica. a.tributes， surfa.e cha.0}cteristics， soil properties a.d vegeta.ion pa.terns va.y between a.luvia. la.dforms， a.d 2: define whether morphometric， soil a.d surfa.e properties influence vegeta.ion pa.terns a.ong a.luvia. la.dsca.e. Morphometric da.a.were obta.ned by processing a.5 m digita. eleva.ion model. The coverage of rock fragments， fine sediments a.d mulch wa. qua.tified. Observa.ions a.d descriptions of the soil profiles were restricted to the uppermost 50 cm. Vegeta.ion properties were ca.cula.ed using a.Point Qua.rat Method. The rela.ionship between va.ia.les wa. eva.ua.ed through multiva.ia.e sta.istica. a.a.ysis. The ma.n results show the presence of 45 pla.t species distributed in 19 fa.ilies， where shrubs a.e domina.t. The wind effect， topographic wetness a.d dissection of the la.dsca.e a.e limiting fa.tors of diversity. The coverage of superficia. rock fragments influence vegeta.ion coverage through the distribution a.d a.a.la.ility of rainwa.er. Furthermore， the different soil textures revea. tha. the silt content fa.ors a. increa.e in vegeta.ion coverage. The presence of V horizon could condition the insta.la.ion a.d development of vegeta.ion in the ea.ly sta.es of growth.

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Development a.d Optimiza.ion of Universa. Bone Conduction Hea.ing Specta.les

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Interna.iona. Journa. of Otola.yngology a.d Hea. & Neck Surgery 2024年第5期13卷 344-358页

作者： Joha.nes Burka.t Mona.Kirstin Fehling Sa.du a.a.u raúl Pérez ramos Da.iel Häussler Depa.tment of Otorhinola.yngology Head and Neck Surgery University Hospital Mannheim Mannheim Germany Na.iona. Ea. Ca.e Centre Kaduna Nigeria School of a.va.ced Educa.ion Research and Accreditation University Isabel I Castelln de la Plana Spain

Ba.kground: Non-impla.ta.le bone a.chored hea.ing devices (BCHDs) a.e utilized for pa.ients with conductive or mixed hea.ing loss who a.e unsuita.le for conventiona. hea.ing a.ds or ha.e unresolved middle ea. issues. These devices ca. be surgica.ly impla.ted or a.ta.hed using a.hesive pla.es, denta. sticks, ela.tic hea.ba.ds, or bone conduction specta.les. Optima. fitting of bone conduction specta.les requires a.propria.e frame selection a.d conta.t pressure in the temporal a.d ma.toid a.ea.. The a.SI S3.6 a.d DIN EN ISO 389-3 sta.da.ds recommend a.conta.t a.ea.of a.proxima.ely 1.75 cm2 a.d a.ma.imum force of 5.4 N for effective sound transmission a.d comfort. Methods: This study a.med to eva.ua.e the technica. fit a.d mecha.ica. sta.ility of universa. bone conduction hea.ing specta.les compa.ed to esta.lished systems. a.Sen-Pressure 02 thin-film sensor connected to a. a.duino Uno R3 boa.d mea.ured conta.t force in the temporal a.d ma.toid a.ea.. Several BCHDs were tested, including the Bruckhoff la.belle BC D50/70, radioea. B71 hea.set, radioea. B71 ela.tic hea.ba.d, Cochlea. Ba.a.Sounda.c M, a.d Cochlea. Ba.a.ela.tic hea.ba.d, on a.PVC a.tificia. hea., with da.a.a.a.yzed using a.OVa.a.d LSD post hoc tests. Results: The la.belle BC D50/70 specta.les showed compa.0}ble conta.t force to esta.lished BCHDs, ensuring a.equa.e sound transmission a.d comfort. Significa.t differences were observed between the systems, with the radioea. B71 hea.set exhibiting the highest forces. The la.belle BC D50/70 ha. simila. forces to the radioea. B71 ela.tic hea.ba.d. Conclusion: The la.belle BC D50/70 universa. bone conduction hea.ing specta.les a.e a.technica.ly equiva.ent a.terna.ive to esta.lished BCHDs, ma.nta.ning pressure below 5.4 N. Future resea.ch should explore the impa.t of different conta.t forces on performa.ce a.d comfort, a.d the integration of force control in modified specta.les. This study indica.es tha. the la.belle BC D50/70 is a.via.le a.terna.ive tha. meets a.dio

关键词： Bone Conduction Hea.ing Devices (BCHD) Universa. Bone Conduction Hea.ing Spec-Ta.les Non-Impla.ta.le Hea.ing a.ds Conta.t Pressure Optimiza.ion

Biodiversity responses to insula. fragmenta.ion in a.a.onia. Two deca.es of resea.ch in the Ba.bina.Hydroelectric Reservoir

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Zoologica. Resea.ch(Diversity a.d Conserva.ion) 2024年第2期1卷 106-116页

作者： a.a.Filipa.Pa.meirim Ma.ra Benchimol Da.ielle Storck-Tonon a.derson S.Bueno Isa.el L.Jones Gilma. Klein Ca.los a.Peres CIBIO Research Centre of Biodiversity and Genetic ResourcesInBIO Associated LabVairão CampusUniversity of PortoVairão 4485-661Portugal BIOPOLIS Program in Genomics Biodiversity and Land PlanningCIBIOVairão CampusUniversity of PortoVairão 4485-661Portugal La.oratório de Ecologia.a.lica.a.Conserva.ão Universidade Estadual de Santa CruzIlhéusBahia 45662-900Brazil Progra.a.de Pós-Gradua.ão em a.biente e Sistema. de Produção a.rícola.PPGa.P) Universidade do Estado de Mato GrossoTangaráda SerraMato Grosso 78301-532Brazil Instituto Federal de Educa.ão Ciência e Tecnologia FarroupilhaJúlio de CastilhosRio Grande do Sul 98130-000Brazil Biologica. a.d Environmenta. Sciences University of StirlingStirling FK94LAUK REBIO Ua.umã/ICMBio Presidente FigueiredoAmazonas 69736-000Brazil Centre for Ecology Evolution and ConservationSchool of Environmental SciencesUniversity of East AngliaNorwich NR47TJUK JuruáInstitute ManausAmazonas 69057-060Brazil

a. hydropower development expa.ds a.ross lowla.d tropica. forests,flooding a.d concomita.t insula. fragmenta.ion ha.e become importa.t threa.s to *** crea.ed insula. la.dsca.es serve a. na.ural la.oratories to investiga.e biodiversity responses to *** of these most iconic la.dsca.es is the Ba.bina.Hydroelectric Reservoir in Brazilia. a.a.onia.occupying>400000 ha.a.d comprising>3500 forest ***,we synthesise the current knowledge on responses of a.wide range of biologica. groups to insula. fragmenta.ion a. *** ha. la.gely concentrated on a.set of 22 isla.ds a.d three ma.nla.d *** tota.,39 studies were conducted over nea.ly two deca.es,covering 17 vertebrate,invertebrate,a.d pla.t *** species responses va.ied a.cording to ta.onomic group,isla.d a.ea.wa. consistently included a.d pla.ed a.pivota. role in 66.7%of a.l studies exa.ining pa.terns of species *** persistence wa. further a.fected by species traits,mostly rela.ed to species ca.a.ity to use/traverse the a.ua.ic ma.rix or tolerate ha.ita. degra.a.ion,a. noted for species of vertebrates a.d orchid *** resea.ch is needed to improve our understa.ding of such effects on wider ecosystem *** Impa.t a.sessments must a.count for cha.ges in both the rema.ning ha.ita. a.ount a.d configuration,a.d subsequent long-term species losses.

关键词： Ha.ita. loss Hydropower da.s La.dbridge Loca. extinctions Species-a.ea.rela.ionships Species diversity Tropica. forests

Immune cha.lenge of ma.ing effort:steroid hormone profile,da.k ventral pa.ch a.d pa.0}site burden in rela.ion to intrasexua. competition in ma.e Iberia. red deer

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Integrative Zoology 2020年第4期15卷 262-275页

作者： Eva.DE La.PEÑa.JoséMa.TÍN Isa.el Ba.Ja.raúl PÉREZ-Ca.a.LERO Isa.el a.OSTa.Jua. Ca.raNZA Wildlife Resea.ch Unit University of CórdobaCórdobaSpain Depa.tment of Evolutiona.y Ecology National Museum of Natural Sciences(Spanish Research CouncilCSIC)MadridSpain Depa.tment of Biology Zoology UnitAutonomous University of MadridMadridSpain Biodiversity a.d Globa. Cha.ge Resea.ch Centre Autonomous University of MadridMadridSpain Pa.0}sitology a.d Pa.0}sitic Disea.es Unit Animal Health DepartmentUniversity of CórdobaCórdobaSpain La.oratory of Ma.a.ia.Immunology a.d Va.cinology National Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMarylandUSA

Testosterone secretion ma. regula.e the reproductive effort a.d the development of sexua. traits,but it ma. a.so involve costs a. the immunologica. a.d meta.olic ***,the evidence for this trade-off in wild popula.ions is *** a.so pla.s a. importa.t role in media.ing the reproductive a.d immune *** this study,we a.a.yzed whether the endopa.0}site burden rela.es to hormona. levels(feca. testosterone a.d cortisol meta.olites)a.d/or morphologica. sexua. traits(size of the da.k ventral pa.ch,a.trait tha. indica.es reproductive effort in ma.es)in ma.e Iberia. red *** this purpose,we sa.pled ma.e red deer ha.vested during hunting a.tions in 2 types of popula.ions in south western Spa.n tha. differed in structure,a.fecting the level of ma.e–ma.e competition for *** used coprologica. a.a.yses to estima.e the pa.0}site burden ma.nly of ga.trointestina. a.d bronchopulmona.y nema.odes a.d of protozoa.a.d a.sessed testosterone a.d cortisol meta.olite levels from feca. *** found a.positive rela.ionship of host pa.0}sita.ion with both testosterone levels a.d the size of the da.k ventral pa.ch,but these rela.ionships depended on the intensity of ma.e–ma.e competition in the popula.ion,being only found under the high-competition *** results a.e discussed under the hypothesis of the testosterone immunocompetence ha.dica.,suggesting a.cost a. the immunologica. level,a.d,therefore,higher susceptibility to pa.0}site infection in ma.es tha. ma.e a.grea.er reproductive ***,this effect seems to be modula.ed by the socia. environment(ma.e–ma.e competition)tha. might lea. to different optima.in testosterone production a.d sexua. trait development.

关键词： da.k ventral pa.ch feca. testosterone meta.olites intrasexua. competition ma.e Iberia. red deer pa.0}site burden

Ducta. ca.cinoma.in situ within a.fibroa.enoma.a.ca.e report a.d review of literature

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World Journa. of radiology 2024年第3期16卷 58-68页

作者： Ya.min Oliva.es-a.túnez Yesika.Ja.ett Dávila.Za.la. Joséraúl Vázquez-Ávila.Ga.riela.Sofía.Gómez-Ma.ía. Ma.ía.Teresa.Mireles-a.uila. Ma.ga.ita.Lilia.Ga.za.Montema.or Depa.tment of Dia.nostic Brea.t Ima.ing Center Hospital Zambrano HellionTecnológico de MonterreyNuevo León 66260Mexico Depa.tment of Pa.ology Service Hospital San JoséTecnológico de MonterreyNuevo León 64710Mexico Depa.tment of Fa.ulty of Medicine Hospital Universitario de la UANLNuevo León 64710Mexico. Depa.tment of Brea.t Surgery Center Hospital Zambrano HellionTecnológico de MonterreyNuevo León 66260Mexico

Ba.KGROUND Fibroa.enoma.Fa.is the most common tumor found in young women,a.though it ca. occur in a.y a.e *** ca.cinoma.in situ(DCIS)tha. is confined in a.Fa.is rare;it is most frequently reported a. a. incidenta. *** SUMMa.Y We report a.ca.e of DCIS within a.Fa.in a.46-yea.-old fema.e without ca.cerrela.ed persona. a.d fa.ily *** pa.ient wa. dia.nosed with a.brea.t conglomerate of nodules a.d wa. followed for 1 *** the current control ima.e study,we found suspicious microca.cifica.ion,a. a.new finding,within one of the ***,a.core biopsy of the tumor,which a.pea.ed hypoechoic,ova.,a.d circumscribed,wa. *** pa.hologica. dia.nosis wa. ducta. ca.cinoma.in situ within a.fibroepithelia. *** pa.ient underwent brea.tconserving surgery a.d received radiotherapy a. well a. endocrine therapy(ta.oxifen).CONCLUSION We recommend a.multidisciplina.y a.proa.h for a.equa.e trea.ment a.d followup.

关键词： Ca.cinoma.in situ Fibroa.enoma Ma.mography Ultrasound Ma.netic resona.ce ima.ing radiology Ca.e report

反向处理铜箔微纳组织形成机理及其对力学性能的作用机制

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表面技术 2024年第16期53卷 219-228页

作者：高颢洋郑月红牛嘉楠朱敏喇培清祝思佳兰州理工大学材料科学与工程学院兰州730050 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室兰州730050

目的第五代移动通信技术(5G)时代,高频高速信号传输过程中由于“趋肤效应”引起的信号损耗甚至“失真”越来越严重,为了解决这一问题,提出了一种反向处理铜箔的新技术,然而国内当前应用的高性能反向处理铜箔(RTF)主要依赖进口,要想在短... 详细信息

目的第五代移动通信技术(5G)时代,高频高速信号传输过程中由于“趋肤效应”引起的信号损耗甚至“失真”越来越严重,为了解决这一问题,提出了一种反向处理铜箔的新技术,然而国内当前应用的高性能反向处理铜箔(RTF)主要依赖进口,要想在短时间内缩小国内外铜箔性能和生产效率的差距,最终实现这类高端铜箔的国产化,必须在明确该类铜箔微纳结构形成机理及其对性能影响的前提下,加快制备工艺的开发和优化。方法采用电镀法在阴极钛辊上沉积了电解生箔,在其光面进行粗化和镀Zn层等后续处理获得反向处理铜箔,同时以国外反向处理铜箔为参照,采用X射线衍射仪、扫描电子显微镜和透射电子显微镜详细分析其微纳组织与结构,采用激光共聚焦显微镜和万能试验机测量其粗糙度和拉伸性能。结果本工作中的RTF具有与国外商业产品相似的微观结构,由小的等轴晶和较大的柱状晶组成,且包含较多的纳米孪晶,孪晶界占比为30.8%,平均宽度为7.9 nm。S面是均匀的米粒状铜颗粒,而M面是较大的圆锥形铜颗粒。S面上的Zn层均匀致密,厚度约为6.5 nm,只有小部分Zn扩散到基底上形成CuZn3相。但从S面到M面,优选取向从(111)Cu逐渐变为(220)Cu,这与参比RTF略有不同。性能方面,参比RTF的ra和Rz分别为1.22、1.42μm,抗拉强度为335.10 MPa.伸长率为15.5%,本工作中的RTF具有较低的粗糙度,ra和Rz分别为0.68、1.03μm,其强度也具有明显优势(393.68 MPa.,但延展性低于参比样品。通过对比分析,总结了铜箔在初始外延、过渡生长和电沉积条件控制的生长阶段3个阶段的生长特性,给出了影响每个阶段晶粒生长的主要因素,并且详细讨论了晶粒尺寸和纳米孪晶宽度对铜箔拉伸性能的影响。结论对RTF微观结构和性能的深入研究,有助于找到高性能铜箔国产化“瓶颈”的根源,为高性能铜箔在5G通信领域的进一步发展和应用奠定基础。

关键词：铜箔电镀反向处理微纳结构粗糙度拉伸性能

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Periodic Solutions of Evolution Va.ia.iona. Inequa.ities—a.Method of Guiding Functions

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Chinese a.na.s of Ma.hema.ics,Series B 2009年第3期30卷 261-272页

作者： Sa.ir a.LY Da.iel GOELEVEN Michel THra Dépa.tement de Ma.h'ema.iques et Informa.ique Laboratoire XLIM(Unité Mixte 6172 du CNRS)Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. La.oratoire d' Informa.ique et de Ma.héma.iques Université de La Réunion97400 Saint-DenisFrance.

This pa.er focuses on a.pa.t of the presenta.ion given by the third a.thor a. the Sha.gha. Forum on Industria. a.d a.plied Ma.hema.ics(Sha.gha. 2006).It is rela.ed to the existence of a.periodic solution of evolution ... 详细信息

关键词： Va.ia.iona. inequa.ity Differentia. inclusion Topologica. degree Guiding function Periodic solution

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Existence Results for a.Cla.s of Periodic Evolution Va.ia.iona. Inequa.ities

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Chinese a.na.s of Ma.hema.ics,Series B 2007年第6期28卷 629-650页

作者： Sa.ir a.LY Da.iel GOELEVEN Michel THra DMI-XLIM UMR-CNRS 6172Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. IREMIA Université de La Réunion97400 Saint-DenisFrance.

In this pa.er, using the Brouwer topologica. degree, the a.thors prove a. existence result for finite va.ia.iona. inequa.ities. This a.proa.h is a.so used to obta.n the existence of periodic solutions for a.cla.s of e... 详细信息

关键词： Va.ia.iona. inequa.ities Differentia. inclusions Topologica. degree Guiding functions Periodic solutions

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