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Soil and climate equally contribute to changes in the species compositions of Brazilian dry forests across 300 km

Journal of Plant Ecology 2020年第2期13卷 171-176页

作者： Daniel M.Arruda Luiz F.S.Magnago ricardo r.c.solar reinaldo Duque-Brasil Priscyla M.S.rodrigues rubens M.Santos carlos E.G.r.Schaefer Instituto de Geociências Universidade Federal de Minas GeraisBelo HorizonteMinas GeraisBrazil centro de Formação em ciências e Tecnologias Agroflorestais Universidade Federal do Sul da BahiaItabunaBahiaBrazil Instituto de ciências Biológicas Universidade Federal de Minas GeraisBelo HorizonteMinas GeraisBrazil Instituto de ciências da Vida Universidade Federal de Juiz de ForaGovernador ValadaresMinas GeraisBrazil colegiado de Ecologia Universidade Federal do Vale do São FranciscoSenhor do BonfimBahiaBrazil Departamento de ciências Florestais Universidade Federal de LavrasLavrasMinas GeraisBrazil Departamento de Solos Universidade Federal de ViçosaViçosaMinas GeraisBrazil

Aims Understanding the factors that control biodiversity distributions at different spatial scales has been a key challenge for conservation *** biodiversity,reflected in differences in species compositions among sites(beta diversity),can be derived from species replacement(turnover)and is driven by multiple ***,we sought to tackle this issue through two questions related to threatened Brazilian seasonally dry forests:(i)what is the contribution of species turnover to beta diversity?and(ii)which factors drive variations in species compositions among forest patches?Methods We sampled tree species and environmental variables(soils and climate)in 17 dry forest patches spaced almost 300 km *** used the beta diversity partitioning framework to determine the contribution of *** used redundancy analysis,with properly controlled spatial structure,to assess the contributions of the environmental and spatial factors to the variations of the species *** Findings Beta diversity among the patches was mainly represented by the turnover component(98.2%),with Simpson dissimilarity superior to other regions of the country(means of 0.89 and 0.71 in multiple site and pairwise measures,respectively).The environmental factors measured explained more than space,representing 30.3%of the variation of the species composition,of which 28.1%was nonspatially *** suggest that 300 km represents a threshold at which edaphic and climatic predictors have similar effects in determining community turnover(14.9%and 12.6%,respectively,without spatial structure).Thus,conservation strategies should be considered across landscapes to effectively protect tropical forest diversity,as even considering the different climatic aspects covered by the scale,landscaped edaphic varieties are important drivers of species turnover.

关键词： beta diversity environmental filter habitat fragmentation landscape structure phytogeography

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Navigating the dynamic landscape of alpha-synuclein morphology: a review of the physiologically relevant tetrameric conformation

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Neural regeneration research 2020年第3期15卷 407-415页

作者： Heather r.Lucas ricardo D.Fernández Department of chemistry Virginia Commonwealth University

N-acetylatedα-synuclein(αSyn)has long been established as an intrinsically disordered protein associated with a dysfunctional role in Parkinson’s *** recent years,a physiologically relevant,higher order conformation has been identified as a helical tetramer that is tailored by buried hydrophobic interactions and is distinctively aggregation *** canonical mechanism by which the tetramer assembles remains *** novel biochemical approaches,computational methods,pioneering purification platforms,and powerful imaging techniques continue to develop,puzzling information that once sparked debate as to the veracity of the tetramer has now shed light upon this new counterpart inαSyn *** magnetic resonance and computational studies on multimericαSyn structure have revealed that the protein folding propensity is controlled by small energy barriers that enable large scale ***,familial mutations ablate tetramerization and reconfigure polymorphic *** this review,we will discuss the dynamic landscape ofαSyn quaternary structure with a focus on the tetrameric conformation.

关键词： alpha-synuclein amyloid fibrils intrinsically disordered protein multimer N-acetylation oligomer Parkinson’s disease protein folding protein structure tetramer

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Updates in penile prosthesis infections

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Asian Journal of Andrology 2020年第1期22卷 28-33页

作者： Amanda r Swanton ricardo M Munarriz Martin S Gross Department of Surgery Section of UrologyDartmouth-Hitchcock Medical CenterLebanonNH 03766USA Department of Urology Boston Medical CenterBostonMA02118USA

Inflatable penile prostheses are an important tool in the treatment of medically refractory erectile *** of the major complications associated with these prostheses is infections,which ultimately require device explanation and placement of a new *** the past several decades,significant work has been done to reduce infection rates and optimize treatment strategies to reduce patient *** article reviews the current state of knowledge surrounding penile prosthesis infections,with attention to the evidence for methods to prevent infection and best practices for device reimplantation.

关键词： erectile dysfunction infection penile prosthesis

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Deep material network via a quilting strategy: visualization for explainability and recursive training for improved accuracy

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npj computational Materials 2023年第1期9卷 1023-1038页

作者： Dongil Shin ryan Alberdi ricardo A.Lebensohn rémi Dingreville center for Integrated Nanotechnologies Sandia National LaboratoriesAlbuquerqueNM 87185USA Simulation Modeling Sciences Sandia National LaboratoriesAlbuquerqueNM 87185USA Theoretical Division Los Alamos National LaboratoryLos AlamosNM 87845USA

recent developments integrating micromechanics and neural networks offer promising paths for rapid predictions of the response of heterogeneous materials with similar accuracy as direct numerical *** deep material network is one such approaches,featuring a multi-layer network and micromechanics building blocks trained on anisotropic linear elastic *** trained,the network acts as a reduced-order model,which can extrapolate the material’s behavior to more general constitutive laws,including nonlinear behaviors,without the need to be ***,current training methods initialize network parameters randomly,incurring inevitable training and calibration ***,we introduce a way to visualize the network parameters as an analogous unit cell and use this visualization to“quilt”patches of shallower networks to initialize deeper networks for a recursive training *** result is an improvement in the accuracy and calibration performance of the network and an intuitive visual representation of the network for better explainability.

关键词： networks Deep network

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Outcome of varicocele repair in men with nonobstructive azoospermia： systematic review and meta-analysis

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Asian Journal of Andrology 2016年第2期18卷 246-253,J0005,J0006页

作者： Sandro c Esteves ricardo Miyaoka Matheus roque Ashok Agarwal ANDrOFErT Center for Male Reproduction Av. Dr. Heitor Penteado 1464 Campinas SP 13075-460 Brazil OrLGEN Center for Reproductive MedicineRio de Janeiro Aw Rodolfo de Amoedo 140 Rio de Janeiro RJ 22620-330 Brazil American center for reproductive Medicine 10681. Carnegie Avenue X-11Cleveland OH 44195 USA.

The objective of this systemic review was to evaluate the benefit of repairing clinical varicocele in infertile men with nonobstructive azoospermia （NOA）. The surgically obtained sperm retrieval rate （Srr） and pregnancy rates following assisted reproductive technology （ArT） with the use of retrieved testicular sperm were the primary outcomes. The secondary outcomes included the presence of viable sperm in postoperative ejaculate to avoid the testicular sperm retrieval and pregnancy rates （both assisted and unassisted） using postoperative ejaculated sperm. An electronic search to collect the data was performed using the MEDLINE and EMBASE databases until April 2015. Eighteen studies were included in this systematic review and accounted for 468 patients who were diagnosed with NOA and varicocele. These patients were subjected to either surgical varicocele repair or percutaneous embolization. Three controlled studies evaluating sperm retrieval outcomes indicated that in patients who underwent varicocelectomy, Srr increased compared to those without varicocele repair （Or： 2,65; 95% cl. 1.69-4.14; P 〈 0.001）. Although pregnancy rates with the use of testicular sperm favored the varicocelectomy group, results were not statistically significant （clinical pregnancy rate Or： 2.07; 95% cI： 0.92-4.65; P = 0.08; live birth rate Or： 2.19; 95% cI： 0.99-4.83; P = 0.05）. The remaining fifteen studies reported postoperative semen analysis results. In 43.9% of the patients （range： 20.8%-55.0%）, sperm were found in postoperative ejaculates. Pregnancy rates for unassisted and assisted （after IVF/IcSI） were 13.6% and 18.9% in the group of men with sperm in postoperative ejaculates, respectively. Our findings indicate that varicocelectomy in patients with NOA and clinical varicocele is associated with improved Srr. In addition, approximately 44% of the treated men will have enough sperm in the ejaculate to avoid sperm retrieval. Limited data on pregnancy outcomes with both postoperative

关键词： azoospermia male infertility meta-analysis sperm retrieval systematic review varicocele varicocelectomy

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ISOPErIMETrIc PrOBLEMS OF THE cALcULUS OF VArIATIONS WITH FrAcTIONAL DErIVATIVES

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Acta Mathematica Scientia 2012年第2期32卷 619-630页

作者： ricardo Almeida rui A.c.Ferreira Delfim F.M.Torres center for research and Development in Mathematics and Applications Department of MathematicsUniversity of Aveiro3810-193 AveiroPortugal Department of Mathematics Faculty of Engineering and Natural SciencesLusophone University of Humanities and Technologies1749-024 LisbonPortugal

In this article, we study isoperimetric problems of the calculus of variations with left and right riemann-Liouville fractional derivatives. Both situations when the lower bound of the variational integrals coincide a... 详细信息

关键词： calculus of variations fractional derivatives isoperimetric problems

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Stand-level biomass models for predicting c stock for the main Spanish pine species

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Forest Ecosystems 2021年第2期8卷 387-402页

作者： Ana Aguirre Miren del río ricardo ruiz-Peinado Sonia condés Department of Natural Systems and resources School of Forest Engineering and Natural ResourcesUniversidad Politécnica de MadridMadridSpain INIA Forest Research CenterDepartment of Forest Dynamics and ManagementMadridSpain iuFOr Sustainable Forest Management Research InstituteUniversity of Valladolid and INIAValladolidSpain

Background:National and international institutions periodically demand information on forest indicators that are used for global *** other aspects,the carbon accumulated in the biomass of forest species must be *** this purpose,one of the main sources of data is the National Forest Inventory(NFI),which together with statistical empirical approaches and updating procedures can even allow annual estimates of the requested ***:Stand level biomass models,relating the dry weight of the biomass with the stand volume were developed for the five main pine species in the Iberian Peninsula(Pinus sylvestris,Pinus pinea,Pinus halepensis,Pinus nigra and Pinus pinaster).The dependence of the model on aridity and/or mean tree size was explored,as well as the importance of including the stand form factor to correct model ***,the capability of the models to estimate forest carbon stocks,updated for a given year,was also ***:The strong relationship between stand dry weight biomass and stand volume was modulated by the mean tree size,although the effect varied among the five pine *** humidity,measured using the Martonne aridity index,increased the biomass for a given volume in the cases of Pinus sylvestris,Pinus halepensis and Pinus *** that consider both mean tree size and stand form factor were more accurate and less biased than those that do *** models developed allow carbon stocks in the main Iberian Peninsula pine forests to be estimated at stand level with biases of less than 0.2 Mg·ha^(-1).conclusions:The results of this study reveal the importance of considering variables related with environmental conditions and stand structure when developing stand dry weight biomass *** described methodology together with the models developed provide a precise tool that can be used for quantifying biomass and carbon stored in the Spanish pine forests in specific years when no field data are available.

关键词： Martonne aridity index Dry weight biomass carbon stock National Forest Inventory Peninsular pine forest Biomass expansion factor

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Engineering Geological Investigations for the Foundations of Large Structures-Examples of a concrete Dam and a long Bridge in Portugal

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Journal of Mountain Science 2011年第2期8卷 296-306页

作者： ricardo OLIVEIrA cOBA and New University of Lisbon Portugal

The safety of large structures requires adequate foundations, which implies a good knowledge of the geological and geotechnical conditions of the respective ground. In general, that is only possible through engineering geological studies which include proper site investigation techniques, adapted to the nature of the ground (rock mass or soil) and to the associated engineering problems. The paper illustrates the studies carried out for the design of the foundations of ribeiradio 76 m high concrete gravity dam in a difficult rock mass and of Vasco da Gama Bridge, 13 km long, crossing the Tagus river in Lisbon, Portugal, through piles 75 m deep.

关键词： Geological investigation Foundations concrete dam Bridge

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characterization and application of tourmaline and beryl from Brazilian pegmatite in adsorption process with divalent metals

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International Journal of Mining Science and Technology 2012年第5期22卷 711-718页

作者： Denis L.Guerra Silze P.Oliveira ricardo A.r.Silva Victor Leidens Adriano c.Batista Federal University of Mato Grosso DRM-ICET-UFMTCuiabá 78060900Brazil Universidade Estadual do Norte Fluminense Rio de Janeiro 2801302Brazil

In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian *** objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate samples,towards divalent metals(Pb 2+,Mn 2+,and Zn 2+) in ethanol solution has been studies by a batch *** ciclosilicate samples were characterized by elemental analysis,Fourier transform infrared spectroscopy,helium picnometry,mercury porosity,and nitrogen *** Langmuir expression for adsorption isotherm was applied in order to determine the adsorption capacity to form a monolayer and the constant related to the adsorption *** aqueous solution there was a significant adsorption increase with the temperature and pronounced synergistic effects were *** maximum number of moles adsorbed was determined to be 12.48 and 11.49 mmol/g for systems Pb 2+ /beryl and Pb 2+ /tourmaline,*** energetic effects caused by metal cations adsorption were determined through calorimetric *** indicated the existence of favorable conditions for such Pb 2+-,Mn 2+-,and Zn 2+-OH interactions.

关键词： Industrial minerals Environmental Pollution Surface modification Wasteprocesing

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The influence of different exercise intensities on kicking accuracy and velocity in soccer players

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Journal of Sport and Health Science 2017年第4期6卷 462-467页

作者： ricardo Ferraz roland van den Tillar Mario c. Marques Department of Sports Sciences University of Beira Interior Convento de St Antonio Covilha 6200-001 Portugal research center in Sport Sciences Health Sciences and Human Development CIDESD Vila Real 5000-801 Portugal Department of Teacher Education Nord Trondelag University College Levanger 7600 Norway

Purpose: The aim of this study was to investigate the influence of different exercise intensities induced by a soccer specific protocol on kicking performance in soccer ***: Twelve semi-professional male soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol to determine the influence of different intensities upon kicking ball velocity and the target-hitting ***: Analysis of variance designs with repeated measures showed that maximal ball velocity was affected only after the most intense circuit(F(6, 66) = 2.3; p = 0.041; η2= 0.18), while accuracy was not affected in the protocol(F(6, 66) = 0.19; p = 0.98; η2= 0.02). Low and moderate intensities did not affect accuracy or kicking ball ***: These findings suggest that kicking ball velocity is influenced by high-exercise intensities. Low and moderate exercise intensities do not affect the performance of the kick, and intensity does not influence accuracy. Otherwise, it is possible that other mechanisms(not only physiological) may influence players during the exercise.

关键词： Exercise intensity Fatigue Kicking soccer Pacing

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