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International Journal of Modeling, Simulation, and Scientific Computing 2014年第S1期5卷 137-145页

作者： Velachi Vasumathi José Luis Cagide Fajin Maria Natália dias Soeiro Cordeiro REQUIMTE Department of Chemistry and Biochemistry University of PortoRua do Campo Alegre 6874168-007PortoPortugal

The structures of self-assembled monolayers(SAMs)of short(methyl)and long(hexyl)chain alkyl thiols on the clean gold(111)surface were modeled using for the Au–S interactions either the reactive ReaxFF potential or the well-known nonreactive Morse potential,while for the Au–Au interactions either the ReaxFF potential or an embeddedatom method(EAM).Analysis of the molecular dynamics(Md)trajectories of possible SAM structures suggests that disordering of interfacial Au atoms is definitely driven by the gold–sulphur *** Md results reveal a novel structure where two methanethiol molecules are bound to a gold adatom that has been lifted from the surface at 300 K,and the same kind of RS–Au–SR motif was also observed for hexanethiol at 600 K but not at 300 *** is more,the above motif is only observed for the reactive ReaxFF ***,these results are in clear agreement with recent experiments and more costly first principles-based Md *** findings strongly support the use of reactive potentials such as ReaxFF for gathering an accurate description of Au–S interactions in inexpensive classical Md simulations.

关键词： Reactive potential alkanethiols self-assembled monolayers gold surface Md simulations

In silico modelling of the corrosion of biodegradable magnesium-based biomaterials:modelling approaches,validation and future perspectives

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Biomaterials Translational 2021年第3期2卷 257-271页

作者： Aditya Joshi George dias Mark P.Staiger department of Mechanical Engineering University of CanterburyChristchurchNew Zealand department of Anatomy University of OtagoDunedinNew Zealand

Metallic biomedical implants based on magnesium,zinc and iron alloys have emerged as bioresorbable alternatives to permanent orthopaedic implants over the last two *** corrosion rate of biodegradable metals plays a critical role in controlling the compatibility and functionality of the device in *** broader adoption of biodegradable metals in orthopaedic applications depends on developing in vitro methods that accurately predict the biodegradation behaviour in ***,the physiological environment is a highly complex corrosion environment to replicate in the laboratory,making the in vitro-to-in vivo translation of results very ***,the results from in vitro corrosion tests fail to provide a complete schema of the biodegradation behaviour of the metal in *** silico approach based on computer simulations aim to bridge the observed differences between experiments performed in vitro and vivo.A critical review of the state-of-the-art of computational modelling techniques for predicting the corrosion behaviour of magnesium alloy as a biodegradable metal is presented.

关键词： biomaterial biodegradation corrosion finite element method magnesium modelling

Phylogeny and evolution of Perezia(Asteraceae:Mutisieae:Nassauviinae)

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Journal of Systematics and Evolution 2009年第5期47卷 431-443页

作者： Beryl B.SIMPSON Mary T.K.ARROYO Sandra SIPE Marta dias de MORAES Joshua McdILL Integrative Biology and Plant Resources Center The University of Texas1 University Station A6700AustinTX 78712USA Facultad de Ciencias Universidad de ChileCasilla 653Santiago de ChileChile Universidade Federal do Acre Campus FlorestaCruzeiro do SulAcreBrazil

A molecular phylogenetic analysis of most of the species of Perezia reveals that,as traditionally defined,the genus is not monophyletic with two species more closely related to Nassauvia than to *** addition,our results show that Burkartia(Perezia) lanigera is related to Acourtia and is the only member of that clade in South *** remaining species are monophyletic and show a pattern of an early split between a western temperate and an eastern subtropical clade of *** the western clade,the phylogeny indicates a pattern of diversification that proceeded from southern,comparatively low-elevation habitats to southern high-elevation habitats,and ultimately into more northern high-elevation *** most derived clades are found in the high central Andes,where significant radiation has occurred.

关键词： Andes biogeography Mutisieae Nassauviinae Perezia.

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非线性准则下三维加筋边坡稳定性的上限分析

中国公路学报 2018年第2期31卷 124-132页

作者：侯超群邓欣孙志彬 dias d 许敬叔合肥工业大学汽车与交通工程学院安徽合肥230601 格勒诺布尔-阿尔卑斯大学3SR实验室伊泽尔格勒诺布尔38041 中南大学土木工程学院湖南长沙410006

为了研究非线性摩尔-库仑破坏准则下的三维加筋边坡在均匀加筋和三角形加筋2种加筋模式下的稳定性,采用极限分析上限理论,构建加筋边坡破坏的三维破坏机构,推导不同加筋模式下的筋材内能耗散方程,并根据上限定理将三维加筋边坡的稳定性... 详细信息

为了研究非线性摩尔-库仑破坏准则下的三维加筋边坡在均匀加筋和三角形加筋2种加筋模式下的稳定性,采用极限分析上限理论,构建加筋边坡破坏的三维破坏机构,推导不同加筋模式下的筋材内能耗散方程,并根据上限定理将三维加筋边坡的稳定性问题转化为显式优化问题,得到三维边坡稳定性指标的计算公式。采用MATLAB软件计算,将结果与已有研究成果进行比较,验证了所提出计算方法的正确性,并进一步讨论了非线性参数m、宽高比B/H、不同加筋模式以及不同加筋强度k0对三维边坡稳定性的影响。结果表明:稳定性系数Ns随着m的增加而非线性减小,在坡角较小(不大于60°)的情况下,m对边坡稳定性系数Ns的影响较大,边坡的非线性特性比较明显;稳定性系数Ns随着B/H的增加而减小,在B/H<5尤其B/H<2时,稳定性系数下降速率较快,B/H越接近10时稳定性系数逐渐趋于稳定;三角形加筋模式的加固效果优于均匀加筋模式,稳定系数性Ns随着加筋强度k0的增加而线性增大,但变化规律并不显著。在实际工程中,建议B/H较小时,要对加筋边坡进行三维分析以符合工程实际;坡角较小时需要考虑土体的非线性破坏特征,选取合适的非线性参数可避免不安全的设计;在工程条件允许的情况下,优先选择三角形加筋模式进行边坡加固。

关键词：道路工程三维稳定性分析极限分析三维边坡加筋边坡非线性破坏准则稳定性系数

Attributes of stand-age-dependent forest determine technosol fertility of Atlantic forest re-growing on mining tailings in Mariana,Brazil

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Journal of Forestry Research 2022年第1期33卷 103-116页

作者： Pedro Manuel Villa Sebastião Venâncio Martins Aline Pilocelli Gabriel Correa Kruschewsky Andreia Aparecida dias Fabio Haruki Nabeta Forest Restoration Laboratory Department of Forest EngineeringUniversidade Federal de ViçosaViçosaMinas GeraisBrazil Fundação Renova Belo HorizonteMinas GeraisBrazil

Understanding how soil fertility changes due to environmental conditions and stand-age-dependent forest attributes is important for local-scale forest *** evaluated the effects of stand-age-dependent forest attributes(plant community composition and litter stock)on soil and technosol fertility across two second-growth Atlantic forests(SGF)after the deposition of mining tailings in Mariana,southeastern *** hypothesized that technosol fertility in the SGF tailings is positively affected by plant community composition variability,stand age,and litter *** used total exchangeable bases and organic matter as fertility indicators for technosol and soil,and species composition and litter stock as stand-age-dependent forest *** results showed significant differences in the stand-age-dependent forest attributes and soil chemical properties between the two forest patches(SGF tailing and SGF non-tailing)***,there was a marked gradient of litter storage and fertility between soil and technosol that can be important forest recovery indicators for the affected plant ***,according to the tested models,we corroborated the hypothesis that technosol fertility is positively affected by stand age,plant community composition variability,and litter stock,which may contribute considerably to forest recovery on *** results demonstrate that the fertility predictors analyzed to explain the forest recovery on tailings can also be considered as ecological indicators for assessing forest restoration in areas impacted by mining tailings in Mariana.

关键词： Ecological indicators Forest recovery Litter stock Nutrient recovery Technosol

Modelling ballistic impact on military helmets:The relevance of projectile plasticity

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defence Technology（防务技术） 2021年第5期17卷 1699-1711页

作者： A.Caçoilo R.Mourao F.Teixeira-dias A.Azevedo F.Coghe R.A.F.Valente School of Engineering The University of EdinburghEdinburghEH93FGUK dept.Weapon Systems and Ballistics Royal Military AcademyBrusselsBelgium Centre for Mechanical Technology and Automation Department of Mechanical EngineeringUniversity of AveiroPortugal

The need to develop armour systems to protect against attacks from various sources is increasingly a matter of personal,social and national *** develop innovative armour systems it is necessary to monitor developments being made on the type,technology and performance of the threats(weapons,projectiles,explosives,etc.) Specifically,the use of high protection level helmets on the battlefield is *** development of evaluation methods that can predict injuries and trauma is therefore of major ***,the risk of injuries or trauma that can arise from induced accelerations is an additional *** develop new materials and layouts for helmets it is necessary to study the effects caused by ballistic impacts in the human head on various *** use of numerical simulation is a fundamental tool in this *** work here presented focuses on the use of numerical simulation(finite elements analysis) to predict the consequences of bullet impacts on military helmets on human *** main objectives are to assess the level and probability of head trauma using the Head Injury Criterion,caused by the impact of a 9 mm NATO projectile on a PASGT helmet and to quantify the relevance of projectile plasticity on the whole modelling *** accelerations derived from the impact phenomenon and the deformations caused on the helmet are evaluated using fully three-dimensional models of the helmet,head,neck and *** studies are done at impact angles ranging from 0 to 75°.Results are presented and discussed in terms of HIC and probability of acceleration induced trauma *** comparison analyses are done using a rigid and a deformable projectile and it is observed that plastic deformation of the projectile is a significant energy dissipation mechanism in the whole impact process.

关键词： Ballistic impact Helmet impact Plasticity Finite element analysis Injury Trauma HIC

Addition of respiratory exercises to conventional rehabilitation for children and adolescents with cerebral palsy:a systematic review and meta-analysis

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World Journal of Pediatrics 2023年第4期19卷 340-355页

作者： Thálita Raysa de Lima Crispim Mansueto Gomes Neto Tafnes Rayane Lima Crispim Renivaldo Batista dias Maria déborah Monteiro de Albuquerque Micheli Bernardone Saquetto Paulo André freire Magalhães Research Group of Neonatal and Pediatric Physical Therapy Baby GrUPEPetrolinaPernambucoBrazil Postgraduate Program in Rehabilitation and Functional Performance PPGRDFUniversidade de PernambucoRodovia BR 203Km 2 S/N.Vila EduardoPetrolinaPernambuco56328-900Brazil Research Group of Physiotherapy Department of Physical TherapyUniversidade Federal da BahiaSalvadorBrazil Posgraduate Program in Medicine and Health SalvadorBahiaBrazil

Background Respiratory dysfunctions are an important cause of morbidity and death in cerebral palsy(CP)*** exercises in addition to conventional rehabilitation have been suggested to improve respiratory status in CP *** objective of this systematic review and meta-analysis was to verify the effects of the addition of respiratory exercises to conventional rehabilitation on pulmonary function,functional capacity,respiratory muscle strength,gross motor function and quality of life in children and adolescents with *** We searched for randomized controlled clinical trials in PubMed/Medline,Lilacs,SciELO,EMBASE and Physi-otheraphy Evidence(PEdro)from their inception until July 2022 without language *** that included respiratory exercises(breathing exercise program;feedback respiratory training;incentive spirometer exercise;inspiratory muscle training;and combination of respiratory exercises+incentive spirometer exercise)in combination with conventional rehabilitation for children and adolescents with CP were evaluated by two independent *** mean difference(Md)and 95%confidence interval(CI)were estimated by random effect *** Ten studies met the eligibility criteria,including 324 children aged from 6 to 16 *** meta-analysis showed an improvement in inspiratory muscle strength of 22.96 cmH2O(18.63-27.27,n=55)and pulmonary function of 0.60(0.38-0.82,n=98)for forced vital capacity(L);0.22(0.06-0.39,n=98)for forced expiratory volume at 1 second(L);and 0.50(0.05-0.04,n=98)for peak expiratory flow(L/min).Functional skills in daily living activities improved in the intervention ***'assistance of daily living activities,functional capacity,gross motor function and expiratory muscle strength showed a nonsignificant *** well-being and acceptance and functioning domains improved in only one *** Emerging data show significant enhancements in inspiratory muscle stren

关键词： Breathing exercises Cerebral palsy Inspiratory muscle training Pediatrics Rehabilitation Respiratory exercise

The interplay between leaf water potential and osmotic adjustment on photosynthetic and growth parameters of tropical dry forest trees

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Journal of Forestry Research 2023年第1期34卷 177-186页

作者： Tiago de Sousa Leite Romulo Magno Oliveira de freitas Nildo da Silva dias Jeferson Luiz dallabona dombroski Narjara Walessa Nogueira Federal University of Mato Grosso CuiabáMTBrazil Federal Institute of Education Science and Technology of Rio Grande do NortePau dos FerrosRNBrazil Federal Rural University of the Semi-Arid Region MossoróRNBrazil

Mimosa tenuiflora and Piptadenia stipulacea are commonly accepted as drought-tolerant species but little is known about their response to drought followed by ***,the interplay between leaf water potential and osmotic adjustment on photo synthetic and growth parameters of these species was examined.A greenhouse study was conducted in a split-plot design with two water conditions in the main plots(control;drought followed by rehydration),and eight sampling times in the subplots(1,4and 7 days of drought,and 1,3,6,12,and 17 days of rehydration).Plant water status and biochemical changes were assessed as well as leaf gas exchange and subsequent *** drought stress,both species maintained a low leaf water potential throughout the day by accumulating compatible solutes,thus allowing a rapid and full recovery of water status when *** these plants minimized water loss by closing their stomata,neither showed stomatal limitations to *** inhibition of this process during drought was possibly related to mesophyll limitations as well as to a reversible downregulation of photo systems,along with adjustments of their *** deficits also triggered morphological adaptations at the whole plant level,leading to reduced growth,mainly of the shoots in *** and the roots in ***.

关键词： drought stress Rehydration Gas exchange Plant biomass

软土地面中机械化双叠隧道的三维数值模拟(英文)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第11期15卷 896-913页

作者： Ngoc-Anh dO daniel dias Pierpaolo ORESTE Laboratory LGCIE INSA of LyonUniversity of LyonVilleurbanneFrance Faculty of Civil Engineering Department of Underground and Mining ConstructionHanoi University of Mining and Geology Laboratory LTHE Grenoble Alpes University department of Environmental Land and Infrastructural EngineeringPolitecnico of TorinoTorinoItaly

研究目的:通过三维数值模拟,研究隧道施工过程对双叠隧道的影响。创新要点:使用全三维数值模拟方法研究软土中双叠隧道施工对先挖隧道或地面的影响。研究方法:1.运用FLAC软件创建双叠隧道的三维数值模型(图1);2.分情况模拟机械化双叠隧... 详细信息

研究目的:通过三维数值模拟,研究隧道施工过程对双叠隧道的影响。创新要点:使用全三维数值模拟方法研究软土中双叠隧道施工对先挖隧道或地面的影响。研究方法:1.运用FLAC软件创建双叠隧道的三维数值模型(图1);2.分情况模拟机械化双叠隧道的挖掘过程;3.研究不同情况下的地面沉降,水平地面位移,以及隧道衬砌的法向位移、法向力、纵向力和弯曲力矩等。重要结论:1.新隧道施工对现有的隧道有很大的影响,最大影响出现在先挖上层隧道的情况下;2.一般来说,上层隧道的挖掘会比下层隧道产生更大的地面沉降;3.下层隧道产生的法向力总是比上层隧道大;4.在多数情况下,下层隧道产生的法向位移和弯曲力矩要比上层隧道小。

关键词：三维模型重叠隧道段隧道衬砌衬砌响应地面沉降隧道支护

A co-interaction model of HIV and syphilis infection among gay,bisexual and other men who have sex with men

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Infectious disease Modelling 2020年第1期5卷 855-870页

作者： Jummy Funke david Viviane dias Lima Jielin Zhu fred Brauer department of Mathematics University of British ColumbiaVancouverBCV6T 1Z2Canada British Columbia Centre for Excellence in HIV/AIdS St.Paul’s HospitalVancouverBCV6Z 1Y6Canada department of Interdisciplinary Studies University of British ColumbiaVancouverBCV6T 1Z4Canada department of Medicine Faculty of MedicineUniversity of British ColumbiaVancouverBCV6T 1Z3Canada

We developed a mathematical model to study the co-interaction of HIV and syphilis infection among gay,bisexual and other men who have sex with men(gbMSM).We qualitatively analysed the model and established necessary conditions under which disease-free and endemic equilibria are asymptotically *** gave analytical expressions for the reproduction number,and showed that whenever the reproduction numbers of sub-models and co-interaction model are less than unity,the epidemics die out,while epidemics persist when they are greater than *** presented numerical simulations of the full model and showed qualitative changes of the dynamics of the full model to changes in the transmission *** numerical simulations using a set of reasonable parameter values showed that:(a)both diseases die out or co-exist whenever their reproduction number is less than or exceed unity.(b)HIV infection impacts syphilis prevalence negatively and vice versa.(c)one possibility of lowering the co-infection of HIV and syphilis among gbMSM is to increase both testing and treatment rates for syphilis and HIV infection,and decrease the rate at which HIV infected individuals go off treatment.

关键词： HIV Syphilis Mathematical model gbMSM Reproduction number Testing and treatment Stability