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Review of plant biogeographic studies in Brazil

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Journal of Systematics and Evolution 2009年第5期47卷 477-496页

作者： pedro FIASCHI José R.PIRANI Department of Biology Virginia Commonwealth University Departamento de Botanica Instituto de BiocienciasUniversidade de So Paulo

Molecular phylogenetic studies have become a major area of interest in plant systematics,and their impacts on historical biogeographic hypotheses are not to be *** Brazil,most historical biogeographic studies have relied on animal phylogenies,whereas plant biogeographic studies have largely lacked a phylogenetic component,having a limited utility for historical *** country,however,is of great importance for most biogeographic studies of lowland tropical South America,and it includes areas from a number of biogeographic regions of the *** biogeographic reports have been published as part of phylogenetic studies,taxonomic monographs,and regional accounts for small areas or phytogeographic domains,but the available information is subsequently scattered and sometimes hard to *** this paper we review some relevant angiosperm biogeographic studies in *** we briefly discuss the importance of other continents as source areas for the South American *** we present a subdivision of Brazil into phytogeographic domains,and we cite studies that have explored the detection of biogeographic units(areas of endemism) and how they are historically related among those *** of plant taxa that could be used to test some biogeographic hypotheses are provided throughout,as well as taxa that exemplify several patterns of endemism and disjunction in the Brazilian angiosperm flora.

关键词： angiosperms biogeography Brazil disjunction distribution patterns endemism.

Employing electrochemically derived pH gradients for Lab-on-PCB protein preconcentration devices

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Microsystems & Nanoengineering 2024年第1期10卷 79-87页

作者： grace Maxted pedro Estrela Despina Moschou Department of Electronic and Electrical Engineering University of BathBath BA27AYUK Centre for Bioengineering and Biomedical Technologies(CBio) University of BathBath BA27AYUK

Protein preconcentration is an essential sample preparation step for analysis in which the targeted proteins exist in low concentrations,such as bodily fluids,water,or ***,very few practical implementations of miniaturized protein preconcentration devices have been demonstrated in practice,and even fewer have been integrated with other microanalytical *** approaches rely heavily on additional chemicals and reagents and introduce complexity to the overall *** this paper,we propose a novel miniaturized isoelectric focusing-based protein preconcentration screening device based on electrochemically derived pH gradients rather than existing chemical reagent *** this way,we reduce the need for additional chemical reagents to zero while enabling device incorporation in a seamlessly integrated full protein analysis microsystem via Lab-on-PCB *** apply our previously presented Lab-on-PCB approach to quantitatively control the pH of a solution in the vicinity of planar electrodes using electrochemical acid generation through redox-active self-assembled *** presented device comprises a printed circuit board with an array of gold electrodes that were functionalized with 4-aminothiophenol;this formed a self-assembled monolayer that was electropolymerized to improve its electrochemical *** preconcentration was performed in two *** first was open and needed the use of a holder to suspend a well of fluid above the electrodes;the second used microfluidic channels to enclose small volumes of *** here are the resulting data for protein preconcentration in both these forms,with a quantitative concentration factor shown for the open form and qualitative proof shown for the microfluidic.

关键词： electrochemical proof qualitative

A Study on Modeling and Optimization of Memory Systems

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Journal of Computer Science & Technology 2021年第1期36卷 71-89页

作者： Jason Liu pedro Espina Xian-He Sun School of Computing and Information Sciences Florida International UniversityMiamiFL 33199U.S.A Department of Computer Science Illinois Institute of TechnologyChicagoIL 60616U.S.A

Accesses Per Cycle(APC),Concurrent Average Memory Access Time(C-AMAT),and Layered Performance Matching(LPM)are three memory performance models that consider both data locality and memory assess *** APC model measures the throughput of a memory architecture and therefore reflects the quality of service(QoS)of a memory *** C-AMAT model provides a recursive expression for the memory access delay and therefore can be used for identifying the potential bottlenecks in a memory *** LPM method transforms a global memory system optimization into localized optimizations at each memory layer by matching the data access demands of the applications with the underlying memory system *** three models have been proposed separately through prior *** paper reexamines the three models under one coherent mathematical *** specifically,we present a new memorycentric view of data *** divide the memory cycles at each memory layer into four distinct categories and use them to recursively define the memory access latency and concurrency along the memory *** new perspective offers new insights with a clear formulation of the memory performance considering both locality and ***,the performance model can be easily understood and applied in engineering *** such,the memory-centric approach helps establish a unified mathematical foundation for model-driven performance analysis and optimization of contemporary and future memory systems.

关键词： performance modeling performance optimization memory architecture memory hierarchy concurrent average memory access time

Conformational dynamics as an intrinsic determinant of prion protein misfolding and neurotoxicity

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Neural Regeneration Research 2024年第10期19卷 2095-2096页

作者： Alessandro Cembran pedro Fernandez-Funez Department of Chemistry and Biochemistry University of Minnesota DuluthDuluthMNUSA Department of Biomedical Sciences University of Minnesota Medical SchoolDuluth CampusDuluthMNUSA

The prion protein(PrP) is the key molecular and pathological mediator of prion diseases,a heterogeneous group of brain disorders with fatal *** diseases are rare but deserve special attention because of their unique f... 详细信息

关键词： folding intrinsic dynamics

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t-SNE:A study on reducing the dimensionality of hyperspectral data for the regression problem of estimating oenological parameters

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Artificial Intelligence in Agriculture 2023年第1期7卷 58-68页

作者： Rui Silva pedro Melo-Pinto CITAB-Centre for the Research and Technology of Agro-Environmental and Biological Sciences Inov4Agro-Institute for InnovationCapacity Building and Sustainability of Agri-Food ProductionUniversidade de Trás-os-Montes e Alto DouroQuinta dos PradosVila Real 5000-801Portugal Departamento de Engenharias Escola de Ciências e TecnologiaUniversidade de Trás-os-Montes e Alto DouroQuinta dos PradosVila Real 5000-801Portugal

In recent years there is a growing importance in using machine learning techniques to improve procedures in precision agriculture:in this work we perform a study on models capable of predicting oenological parameters from hyperspectral images of wine grape berries,a specially relevant topic to boost production tasks for ***,we explore the capabilities of a novel technique mostly used for visualization,t-Distributed Stochastic Neighbor Embedding(t-SNE),for reducing the dimensionality of the highly complex hyperspectral data and compare its performance with Principal Component Analysis(PCA)method,which despite the introduction of many nonlinear dimensionality reduction techniques over the years,had achieved the best results for real-world data across several studies in *** we explore the potential of Kernel t-SNE,an extension to the t-SNE method that allows for the usage of the technique in streaming data or online *** results show that,in a direct comparison,t-SNE achieves better metrics than PCA for most of the data sets in this work and that the regressor(Support Vector Regression,SVR)performs better with the t-SNE reduced features as inputs,accomplishing better predictions with lower error *** the results with current literature,our shallow learning model paired with t-SNE achieves either better or on par results than those reported,even competing with more advanced models that use deep learning techniques,which should propel the introduction of t-SNE in more studies that require dimensionality reduction.

关键词： Hyperspectral images Dimensionality reduction Regression T-SNE Support vector machines Wine grape berries

One DOF mechanism for the mechanical harvest of vines in an arbor structure and the validation of the acceleration of grape berry harvesting

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Frontiers of Mechanical Engineering 2015年第3期10卷 221-232页

作者： pedro BOCCA Facultad de Ingenieria Universidad Nacional de San Juan San Juan5400 Argentina

In the mechanized harvest of vines, grape berries are detached through the vibration to the structure supporting the clusters. According to the kind of guide selected, the clusters require one or two vibration directions in the structure. For guiding in parral structures, vibration is necessary in two directions or planes： One perpendicular to the other. The guide branches producing the clusters develop in these planes, and the guiding is called H-guiding. Mechanism theory indicates that a mechanism has as many degrees of freedom as its actuators, and an actuator is needed to achieve a certain vibration. Having the smallest number of possible actuators is beneficial in reducing moving parts and achieving more compact and easily controllable mecha- nisms. In this case, a single degree-of-freedom mechanism is proposed. It is capable of generating vibrations on two planes： One perpendicular to the other. This mechanism is the sum of two link mechanisms on perpendicular planes with a common outlet located at the output rod of the mechanism where the actuator is found. As the distance between the soil and the elements containing the clusters is not constant, a system has been designed to measure the accelerations at the bars and the rocker to validate the acceleration values that detach the grape berries in a prototype in a lab experiment, to ensure that the acceleration needed for pulling the grape berries are produced at any contact point of the bar.

关键词： harvest mechanisms one DOF vibration

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Effect of the Coulomb and dielectric forces on the onset of Rayleigh-Bénard convection

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Acta Mechanica Sinica 2024年第6期40卷 64-77页

作者： Zhonglin Du pedro A.Vázquez Jian Wu School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China Heilongjiang Key Laboratory of Micro-and Nano-scale Fluid Flow and Heat Transfer Harbin150001China Departamento de Física Aplicada III ETSIIUniversidad de SevillaSevilla41092Spain

In this paper,the effect of Coulomb and dielectric forces on the onset of Rayleigh-Bénard convection(RBC)in a dielectric liquid layer contained between two parallel electrode plates has been numerically *** different operating conditions have been considered in electrohydrodynamic(EHD)conduction:ohmic and saturation,and variations in the physical properties of the dielectric fluid with *** electric equations and the state equations based on the Boussinesq approximation are integrated in the framework of OpenFOAM buoyantBoussinesqPimpleFoam *** results show that in the ohmic regime,the combined effect of Coulomb and dielectric forces promotes the onset of RBC flow,while in the saturation state,the inhibition of RBC flow by Coulomb force is more *** value of the critical Rayleigh number Ra decreases with increasing electric Reynolds number ReE in the ohmic regime,whereas in the saturation state,the critical Ra increases with increasing *** the saturation regime,the flow field always has a steady flow in the range of parameters ***,the onset of the RBC flow promoted by the dielectric force is more pronounced in the ohmic *** to the presence of the dielectric force,the flow field exhibits periodic oscillatory flow at low electric Reynolds numbers for the range of parameters considered.

关键词： EHD conduction Dielectric force Rayleigh-Bénard convection OpenFOAM

High-Efficiency DC-DC Converter for Large Input-Voltage Fluctuations in Solar Applications

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Chinese Journal of Electronics 2015年第3期24卷 502-507页

作者： AgUILLON-gARCIA Jacobo BANUELOS-SANCHEZ pedro SIST Sun Yat-sen University

In the solar energy systems the solar irradiance variation is partially engaged, limiting the converter’s transformation rate for a certain input amount and leaving the rest of energy unconverted. In order to utilize at its maximum the energy provided from a Photovoltaic(PVP) system, this manuscript proposed a topology that can cope with marginal input voltage variations from 60V(DC) up to 1050V(DC) for a steady output voltage of 700V(DC). This output voltage value is suitable for any interlink post-regulation architecture. Based on previous observations, this paper presents a wide-input voltage high-efficiency non-isolated single-control topology. Analysis, operating stages, simulations and experimental results for a 3k W prototype are presented.

关键词： DC-DC power converters Energy conversion Photovoltaic system Power conditioning Solar generation

Colletotrichum species and complexes:geographic distribution,host range and conservation status

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Fungal Diversity 2021年第5期110卷 109-198页

作者： pedro Talhinhas Riccardo Baroncelli LEAF-Linking Landscape EnvironmentAgriculture and Food-Research CentreAssociated Laboratory TERRAInstituto Superior de AgronomiaUniversidade de LisboaTapada da Ajuda1349-017 LisbonPortugal Department of Agricultural and Food Sciences(DISTAL) University of BolognaBolognaItaly

The taxonomy of the genus Colletotrichum has undergone tremendous changes over the last decade,with over 200 species being currently recognised and species complexes being informally used to cluster those *** of these species are important plant pathogens,some rather polyphagous and others host-specific,but several occur seldomly and some may in fact be ecologically *** mainly on literature from the past decade,in this work we review the occurrence,geographic distribution and host spectrum of currently recognised Colletotrichum species under phylogenetic,pathologi-cal/agronomic and ecological perspectives,providing a list arranged by Colletotrichum species and species complexes.A total of 257 species are listed and grouped into 15 species *** this work we have recorded 1353 unique host species-Colletotrichum species association records from 720 hosts,with the Fabaceae as the family with higher number of hosts(52 host species)but with the Rosaceae as the family with the highest number of host species-Colletotrichum species association records(118 association records).According to occurrence data,88 species are common in nature,128 were considered as data deficient and 41 are threatened,some of which are likely extinct from nature and preserved only in cul-ture *** species are relevant plant pathogens,in some cases geographically confined and thus of potential quarantine *** on the major changes that occurred on Colletotrichum taxonomy over the last decade,this work provides a comprehensive overview of occurrence data of Colletotrichum species,compiling host range and geographical distribution,with relevance for plant pathology and conservation *** current taxonomic framework in Colle-totrichum is revealing numerous species but poses challenges to the employment of standard criteria for the evaluation of biological conservation of these *** advocate that conservation mycology and taxonomy should

关键词： Colletotrichum Species complex Taxonomy Host range geographic distribution Conservation mycology