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Stellar structure model in hydrostatic equilibrium in the context of f(R)-gra.ity

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Research in Astronomy and Astrophysics 2017年第12期17卷 31-40页

作者： raíla Andr Gilberto M.Kremer Departamento de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil Manipal Centre for Natural Sciences Manipal UniversityManipal 576104India

in this work we present a stellar structure model from the f（R）-gra.ity point of view capable of describing some classes of stars（white dwarfs, brown dwarfs, neutron stars, red giants and the Sun）. This model is based on f（R）-gra.ity field equations for f（R） = R ＋ f2R2, hydrostatic equilibrium equation and a polytropic equation of state. We compare the results obtained with those found by Newtonian theory. it has been observed that in these systems, where high curvature regimes emerge,stellar structure equations undergo modifications. Despite the simplicity of this model, the results are satisfactory. The estimated values of pressure, density and temperature of the stars are within those determined by observations. This f（R）-gra.ity model has proved to be necessary to describe stars with strong fields such as white dwarfs, neutron stars and brown dwarfs, while stars with weaker fields, such as red giants and the Sun, are best described by Newtonian theory.

关键词： cosmology:theory stars:general massive brown dwarfs white dwarfs neutron

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Vegetation Response To Soil And Morphological Properties in An Arid Region Alluvial Fan landscape. Pre-Andes Of San Juan， Argentina

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Journal of Earth Science 2024年

作者： FLORES Daniel Germán OCA?A raúl Emmanuel MELiáN Edgardo ORTEG Andrés ESPER ANGiLLiERi María Yanina PiTTALUGA María Alejandra CiGEOBiO (CONiCET-UNSJ) Av.José i.de la Roza y Meglioli Gabinete de Geología Ambiental， iNGEO， Universidad Nacional de San Juan， Av.José i.de la Roza y Meglioli

The Monte Desert is characterized by a great diversity of landforms created with fluvial， alluvial which the vegetation patterns are related to. The present work has the following objectives: 1: determine whether topographical attributes， surface characteristics， soil properties and vegetation patterns vary between alluvial landforms， and 2: define whether morphometric， soil and surface properties influence vegetation patterns along alluvial landscape. Morphometric data were obtained by processing a 5 m digital elevation model. The coverage of rock fragments， fine sediments and mulch was quantified. Observations and descriptions of the soil profiles were restricted to the uppermost 50 cm. Vegetation properties were calculated using a Point Quadrat Method. The relationship between variables was evaluated through multivariate statistical analysis. The main results show the presence of 45 plant species distributed in 19 families， where shrubs are dominant. The wind effect， topographic wetness and dissection of the landscape are limiting factors of diversity. The coverage of superficial rock fragments influence vegetation coverage through the distribution and availability of rainwater. Furthermore， the different soil textures reveal that the silt content favors an increase in vegetation coverage. The presence of V horizon could condition the installation and development of vegetation in the early stages of growth.

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Development and Optimization of Universal Bone Conduction Hearing Spectacles

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international Journal of Otolaryngology and Head & Neck Surgery 2024年第5期13卷 344-358页

作者： Johannes Burkart Mona kirstin Fehling Saadu Adamu raúl Pérez ramos Daniel Häussler Department of Otorhinolaryngology Head and Neck Surgery University Hospital Mannheim Mannheim Germany National Ear Care Centre Kaduna Nigeria School of Advanced Education Research and Accreditation University Isabel I Castelln de la Plana Spain

Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. These devices can be surgically implanted or attached using adhesive plates, dental sticks, elastic headbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in the temporal and mastoid areas. The ANSi S3.6 and DiN EN iSO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. Methods: This study aimed to evaluate the technical fit and mechanical stability of universal bone conduction hearing spectacles compared to established systems. A Sen-Pressure 02 thin-film sensor connected to an Arduino Uno R3 board measured contact force in the temporal and mastoid areas. Several BCHDs were tested, including the Bruckhoff la belle BC D50/70, ra.ioear B71 headset, ra.ioear B71 elastic headband, Cochlear Baha SoundArc M, and Cochlear Baha elastic headband, on a PVC artificial head, with data analyzed using ANOVA and LSD post hoc tests. Results: The la belle BC D50/70 spectacles showed comparable contact force to established BCHDs, ensuring adequate sound transmission and comfort. Significant differences were observed between the systems, with the ra.ioear B71 headset exhibiting the highest forces. The la belle BC D50/70 had similar forces to the ra.ioear B71 elastic headband. Conclusion: The la belle BC D50/70 universal bone conduction hearing spectacles are a technically equivalent alternative to established BCHDs, maintaining pressure below 5.4 N. Future research should explore the impact of different contact forces on performance and comfort, and the integra.ion of force control in modified spectacles. This study indicates that the la belle BC D50/70 is a viable alternative that meets audio

关键词： Bone Conduction Hearing Devices (BCHD) Universal Bone Conduction Hearing Spec-Tacles Non-implantable Hearing Aids Contact Pressure Optimization

Biodiversity responses to insular fragmentation in Amazonia: Two decades of research in the Balbina Hydroelectric Reservoir

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Zoological Research(Diversity and Conservation) 2024年第2期1卷 106-116页

作者： Ana Filipa Palmeirim Maíra Benchimol Danielle Storck-Tonon Anderson S.Bueno isabel L.Jones Gilmar Klein Carlos 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 laboratório de Ecologia AplicadaàConservação Universidade Estadual de Santa CruzIlhéusBahia 45662-900Brazil Programa de Pós-Graduação em Ambiente e Sistemas de Produção Agrícola(PPGASP) Universidade do Estado de Mato GrossoTangaráda SerraMato Grosso 78301-532Brazil instituto Federal de Educação Ciência e Tecnologia FarroupilhaJúlio de CastilhosRio Grande do Sul 98130-000Brazil Biological and Environmental Sciences University of StirlingStirling FK94LAUK REBiO Uatumã/iCMBio Presidente FigueiredoAmazonas 69736-000Brazil Centre for Ecology Evolution and ConservationSchool of Environmental SciencesUniversity of East AngliaNorwich NR47TJUK Juruáinstitute ManausAmazonas 69057-060Brazil

As hydropower development expands across lowland tropical forests,flooding and concomitant insular fragmentation have become important threats to *** created insular landscapes serve as natural laboratories to investigate biodiversity responses to *** of these most iconic landscapes is the Balbina Hydroelectric Reservoir in Bra.ilian Amazonia,occupying>400000 ha and comprising>3500 forest ***,we synthesise the current knowledge on responses of a wide range of biological groups to insular fragmentation at *** has largely concentrated on a set of 22 islands and three mainland *** total,39 studies were conducted over nearly two decades,covering 17 vertebrate,invertebrate,and plant *** species responses varied according to taxonomic group,island area was consistently included and played a pivotal role in 66.7%of all studies examining patterns of species *** persistence was further affected by species traits,mostly related to species capacity to use/traverse the aquatic matrix or tolerate habitat degradation,as noted for species of vertebrates and orchid *** research is needed to improve our understanding of such effects on wider ecosystem *** impact Assessments must account for changes in both the remaining habitat amount and configura.ion,and subsequent long-term species losses.

关键词： Habitat loss Hydropower dams landbridge Local extinctions Species-area relationships Species diversity Tropical forests

immune challenge of mating effort:steroid hormone profile,dark ventral patch and para.ite burden in relation to intrasexual competition in male iberian red deer

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integra.ive Zoology 2020年第4期15卷 262-275页

作者： Eva DE la PEÑA JoséMARTÍN isabel BARJA raúl PÉREZ-CABALLERO isabel ACOSTA Juan CARraNZA Wildlife Research Unit University of CórdobaCórdobaSpain Department of Evolutionary Ecology National Museum of Natural Sciences(Spanish Research CouncilCSIC)MadridSpain Department of Biology Zoology UnitAutonomous University of MadridMadridSpain Biodiversity and Global Change Research Centre Autonomous University of MadridMadridSpain Para.itology and Para.itic Diseases Unit Animal Health DepartmentUniversity of CórdobaCórdobaSpain laboratory of Malaria immunology and Vaccinology National Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMarylandUSA

Testosterone secretion may regulate the reproductive effort and the development of sexual traits,but it may also involve costs at the immunological and metabolic ***,the evidence for this trade-off in wild populations is *** also plays an important role in mediating the reproductive and immune *** this study,we analyzed whether the endopara.ite burden relates to hormonal levels(fecal testosterone and cortisol metabolites)and/or morphological sexual traits(size of the dark ventral patch,a trait that indicates reproductive effort in males)in male iberian red *** this purpose,we sampled male red deer harvested during hunting actions in 2 types of populations in south western Spain that differed in structure,affecting the level of male–male competition for *** used coprological analyses to estimate the para.ite burden mainly of gastrointestinal and bronchopulmonary nematodes and of protozoa,and assessed testosterone and cortisol metabolite levels from fecal *** found a positive relationship of host para.itation with both testosterone levels and the size of the dark ventral patch,but these relationships depended on the intensity of male–male competition in the population,being only found under the high-competition *** results are discussed under the hypothesis of the testosterone immunocompetence handicap,suggesting a cost at the immunological level,and,therefore,higher susceptibility to para.ite infection in males that make a greater reproductive ***,this effect seems to be modulated by the social environment(male–male competition)that might lead to different optima in testosterone production and sexual trait development.

关键词： dark ventral patch fecal testosterone metabolites intrasexual competition male iberian red deer para.ite burden

Ductal carcinoma in situ within a fibroadenoma:A case report and review of literature

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World Journal of ra.iology 2024年第3期16卷 58-68页

作者： Yazmin Olivares-Antúnez Yesika Janett Dávila-Zablah Joséraúl Vázquez-Ávila Gabriela Sofía Gómez-Macías María Teresa Mireles-Aguilar Margarita Lilia Garza-Montemayor Department of Diagnostic Breast imaging Center Hospital Zambrano HellionTecnológico de MonterreyNuevo León 66260Mexico Department of Patology Service Hospital San JoséTecnológico de MonterreyNuevo León 64710Mexico Department of Faculty of Medicine Hospital Universitario de la UANLNuevo León 64710Mexico. Department of Breast Surgery Center Hospital Zambrano HellionTecnológico de MonterreyNuevo León 66260Mexico

BACKGROUND Fibroadenoma(FA)is the most common tumor found in young women,although it can occur in any age *** carcinoma in situ(DCiS)that is confined in a FA is rare;it is most frequently reported as an incidental *** SUMMARY We report a case of DCiS within a FA in a 46-year-old female without cancerrelated personal and family *** patient was diagnosed with a breast conglomerate of nodules and was followed for 1 *** the current control image study,we found suspicious microcalcification,as a new finding,within one of the ***,a core biopsy of the tumor,which appeared hypoechoic,oval,and circumscribed,was *** pathological diagnosis was ductal carcinoma in situ within a fibroepithelial *** patient underwent breastconserving surgery and received ra.iotherapy as well as endocrine therapy(tamoxifen).CONCLUSiON We recommend a multidisciplinary approach for adequate treatment and followup.

关键词： Carcinoma in situ Fibroadenoma Mammography Ultrasound Magnetic resonance imaging ra.iology Case report

Effectiveness of menstruation hygiene skills training for adolescents with autism

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World Journal of Psychiatry 2023年第11期13卷 958-966页

作者： Meltem Kaydırak Büşra Yılmaz Merve Azak Çiğdem Bilge Department of Women Health and Gynecologic Nursing Istanbul University-CerrahpaşaFlorence Nightingale Faculty of NursingIstanbul 34381Türkiye Department of Pediatric Nursing Istanbul University-CerrahpaşaFlorence Nightingale Faculty of NursingIstanbul 34381Türkiye Department of Obstetrics and Women's Health Nursing Muğla SıtkıKoçman UniversityFaculty of Health SciencesMuğla 48000Türkiye

BACKGROUND Adolescents with autism spectrum disorder(ASD)may encounter many difficulties with their menstrual *** challenges that adolescents with ASD may face include understanding physical changes,coping with symptoms,emotional sensitivity,communication,personal care,and *** To evaluate the effect of menstrual hygiene skills training given to adolescents with ASD on their menstrual hygiene *** The study was conducted with 15 adolescents diagnosed with ASD by the single group pre-test and post-test model in three special education centers in Tü*** were collected with the Adolescent and Parent information Form and the Adolescent-Specific Menstrual Hygiene Skill Registra.ion *** While the mean age of adolescents was 16.06±0.88 years,the mean age of individuals responsible for adolescent care was 43.66±5.56 *** 60.0%of the adolescents noticed the onset of bleeding before training,this rate was 93.3%after *** Adolescent-Specific Menstrual Hygiene Skill Registra.ion Form showed a statistically significant increase in the application steps after the *** difference between the menstrual hygiene skill scores of adolescents CONCLUSiON The menstrual hygiene skills training given to adolescents with ASD was beneficial in increasing their menstrual hygiene *** individuals must take responsibility during menstruation and independently manage their continuous care activities.

关键词： Autism Adolescent Menstruation Hygiene Training

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 Variational inequalities—a Method of Guiding Functions

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Chinese Annals of Mathematics,Series B 2009年第3期30卷 261-272页

作者： Samir ADLY Daniel GOELEVEN Michel THra Département de Math'ematiques et informatique Laboratoire XLIM(Unité Mixte 6172 du CNRS)Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. laboratoire d' informatique et de Mathématiques Université de La Réunion97400 Saint-DenisFrance.

This paper focuses on a part of the presentation given by the third author at the Shanghai Forum on industrial and Applied Mathematics(Shanghai 2006).it is related to the existence of a periodic solution of evolution ... 详细信息

关键词： Variational inequality Differential inclusion Topological degree Guiding function Periodic solution

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