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The Harvesting of the Endangered Palm Euterpe edulis in the Brazilian Atlantic Forest: The Case of Linear Canopy Openings

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Journal of Geoscience and Environment Protection 2023年第12期11卷 151-162页

作者： Pablo josé francisco Pena rodrigues Mariana de Andrade Iguatemy Talita Reis Instituto de Pesquisas Jardim Botanico do Rio de Janeiro Rua Pacheco Le&#227o Rio de Janeiro Brazil

The palm Euterpe edulis was historically very exploited by humans and even today, many individuals are cut down by collectors to harvest the edible palm hearts. The ecological aspects of this anthropogenic pressure and its related effects are poorly understood. Here we investigate if linear canopy openings in a fragment of Brazilian Atlantic Forest can cause edge effects and facilitate predatory harvesting by humans. We sampled in Tinguá Biological Reserve (Southeastern Brazil) native palm populations at forest edges adjacent to two linear canopy openings, and in the forest interior far from any edge. Our 8-year monitoring showed that the linear canopy openings negatively affected the palm populations reducing its density and regeneration mainly on edges, but no local extinction was observed. Thus, the direct human impact from harvesting, adverse survival conditions on edges and interspecific competition causes population declines with no local extinction, so this suggests that E. edulis may resist even under strong anthropogenic pressure.

关键词： Extinction Exploitation Forest Product Species Survival Sustainability

The effect of water-level fluctuations on swamp forest colonization by seedlings of <i>Tabebuia cassinoides</i>DC. (Bignoniaceae)

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Open Journal of Ecology 2011年第3期1卷 63-64页

作者： Mariana de Andrade Iguatemy Pablo josé francisco Pena rodrigues 不详

Establishment of Tabebuia cassinoides seedlings is related to water-level fluctuations in southeastern Brazil swamp forests. Nine years of annual monitoring of 48 individuals established during a drought in November 1997, when the swamp was unflooded, suggested that their establishment depends on this unpredictable event. This conclusion is further sustained by the wide variability of the seedling cohort size structure, and the fascicular root conformation that holds the shoots erect.

关键词： Tropical Rain Forest Wetland Seedling Establishment Safe Site Root Morphology

The emerging role of mesenchymal stem cell-derived extracellular vesicles to ameliorate hippocampal NLRP3 inflammation induced by binge-like ethanol treatment in adolescence

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Neural Regeneration Research 2025年第4期20卷 1153-1163页

作者： Susana Mellado María joséMorillo-Bargues Carla Perpiñá-Clérigues francisco García-García Victoria Moreno-Manzano Consuelo Guerri María Pascual Department of Physiology School of Medicine and DentistryUniversity of ValenciaValenciaSpain Bioinformatics and Biostatistics Unit Príncipe Felipe Research CenterValenciaSpain Neuronal and Tissue Regeneration Laboratory Príncipe Felipe Research CenterValenciaSpain

Our previous studies have reported that activation of the NLRP3(NOD-,LRR-and pyrin domain-containing protein 3)-inflammasome complex in ethanol-treated astrocytes and chronic alcohol-fed mice could be associated with neuroinflammation and brain *** stem cell-derived extracellular vesicles(MSC-EVs)have been shown to restore the neuroinflammatory response,along with myelin and synaptic structural alterations in the prefrontal cortex,and alleviate cognitive and memory dysfunctions induced by binge-like ethanol treatment in adolescent *** the therapeutic role of the molecules contained in mesenchymal stem cell-derived extracellular vesicles,the present study analyzed whether the administration of mesenchymal stem cell-derived extracellular vesicles isolated from adipose tissue,which inhibited the activation of the NLRP3 inflammasome,was capable of reducing hippocampal neuroinflammation in adolescent mice treated with binge *** demonstrated that the administration of mesenchymal stem cell-derived extracellular vesicles ameliorated the activation of the hippocampal NLRP3 inflammasome complex and other NLRs inflammasomes(e.g.,pyrin domain-containing 1,caspase recruitment domain-containing 4,and absent in melanoma 2,as well as the alterations in inflammatory genes(interleukin-1β,interleukin-18,inducible nitric oxide synthase,nuclear factor-kappa B,monocyte chemoattractant protein-1,and C–X3–C motif chemokine ligand 1)and miRNAs(miR-21a-5p,miR-146a-5p,and miR-141-5p)induced by binge-like ethanol treatment in adolescent *** analysis further revealed the involvement of miR-21a-5p and miR-146a-5p with inflammatory target genes and NOD-like receptor signaling *** together,these findings provide novel evidence of the therapeutic potential of MSC-derived EVs to ameliorate the hippocampal neuroinflammatory response associated with NLRP3 inflammasome activation induced by binge drinking in adolescence.

关键词： adolescence binge-like ethanol treatment extracellular vesicles hippocampus mesenchymal stem cells neuroinflammation NOD-,LRR-and pyrin domain-containing protein 3(NLRP3)

Slip-model Performance for Underexpanded Micro-scale Rocket Nozzle Flows

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Journal of Thermal Science 2007年第3期16卷 223-230页

作者： joséA.Morí■igo joséHermidaQuesada francisco Caballero Requena Dept.of Space Programmes Dept.of

In aerospace Micro-Electro Mechanical Systems （MEMS）, the characteristic length scale of the flow approaches the molecular mean free path, thus invalidating the continuum description and enforcing the use of particle methods, like the Direct Simulation Monte Carlo （DSMC）, to deal with the non-equilibrium regions. Within the slip-regime （0.01〈Kn〈-0.1） both approaches, continuum and particle-based, seem to behave well in terms of accuracy. The present study summarizes the implementation and results obtained with a 2nO-order slip boundary condition in a Navier-Stokes solver to address the rarefaction near the nozzle walls. Its assessment and application to a cold-gas micro-scale conical nozzle of 300μm throat diameter, discharging into the low-pressure freestream, constitutes the major aim of the work. The slip-model incorporates the velocity slip with thermal creep and temperature jump, thus permitting to deal with non-isothermal flows as well. Results show that the gas experiences an intense rarefaction in the lip vicinity, pointing to the limits of model validity. Furthermore, a strong Mach deceleration is observed, attributed to the rather thick subsonic boundary layer and supersonic bulk heating caused by the viscous dissipation, in contrast with the expansion to occur in large rocket nozzles during underexpanded operation.

关键词： Slip flow MEMS micronozzles

Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： francisco E Jorge josé R da Costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities

Glyphosate Dissipation in Different Soils Under No-Till and Conventional Tillage

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Pedosphere 2019年第6期29卷 773-783页

作者： Elena OKADA joséLuis COSTA francisco BEDMAR Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Balcarce 7620(Argentina Estación Experimental Agropecuaria Balcarce Instituto Nacional de Tecnología Agropecuaria(INTA)Balcarce 7620(Argentina Facultad de Ciencias Agrarias Universidad Nacional de Mar del PlataBalcarce 7620(Argentina

Glyphosate is the most used herbicide in Argentina, accounting for 62% of the commercialized pesticides on the market. It is used as a weed controller in no-till systems, and it is also applied to various genetically modified crops ( e.g., soybean, corn, and cotton). Although it has a high solubility in water, it tends to adsorb and accumulate in agricultural soils. The main objectives of this work were to compare the dissipation of glyphosate and the accumulation of its metabolite aminomethylphosphonic acid (AMPA) over time in three soils from agricultural areas of Argentina under long-term management with no-till (NT) and conventional tillage (CT) practices. There were no differences in dissipation between NT and CT, indicating that the glyphosate-degrading microflora was not modified by the different tillage managements. Moreover, tillage practices did not alter the general soil properties;therefore, glyphosate bioavailability was not affected by NT or CT practice. Forty percent of the applied glyphosate was degraded within the first three days in all soils, indicating a fast initial dissipation rate. However, the dissipation rate considerably decreased over time, and the degradation kinetics followed a bi-exponential (or two-compartment) kinetic model. No differences were found between tillage practices. Dissipation was not related to the microbial activity measured as soil respiration. The fast decrease in the concentration of glyphosate at the beginning of the dissipation study was not reflected in an increase in the concentration of AMPA. The estimated half-lives for glyphosate ranged between 9 and 38 d. However, glyphosate bioavailability decreases over time, as it is strongly adsorbed to the soil matrix. This increases its residence time, which may lead to its accumulation in agricultural soils.

关键词： Aminomethylphosphonic acid Bioavailability Biodegradation Herbicide Metabolite Pesticide Two-compartment kinetic model

Powder metallurgy with space holder for porous titanium implants:A review

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Journal of Materials Science & Technology 2021年第17期76卷 129-149页

作者： Alejandra Rodriguez-Contreras Miquel Punset joséA.Calero francisco Javier Gil Elisa Ruperez joséMaría Manero Biomaterials Biomechanics and Tissue Engineering Group(BBT)Department of Materials Science and EngineeringUniversitat Politecnica de Catalunya(UPC)Av.Edurad Maristany 1608019BarcelonaSpain Barcelona Research Centre in Multiscale Science and Engineering Technical University of Catalonia(UPC)Av.Eduard Maristany 10-1408019BarcelonaSpain UPC Innovation and Technology Center(CIT-UPC).Technical University of Catalonia(UPC) C.Jordi Girona 3-108034Barcelona.Spain AMES GROUP SA.Carretera Nacional 340 Pol.Ind."Les Fallulles"08620Sant Vicenc dels HortsBarcelonaSpain Bioengineering Institute for Technology Universitat Intemacional de Catalunyac/Josep Trueta s/n08195BarcelonaSpain

One of the biggest challenges in the biocompatibility of implantable metals is the prevention of the stress shielding effect,which is related to the coupling of the bone-metal mechanical *** stress shielding phenomenon provokes bone resorption and the consequent adverse effects on prosthesis ***,it can be inhibited by adapting the stiffness of the implant *** the use of titanium(Ti)porous structures is a great alternative not only to inhibit this effect but also to improve the osteointegration of orthopedic and dental implants,a brief description of the techniques used for their manufacturing and a review of the current commercialized implants produced from porous Ti assemblies are compiled in this *** powder metallurgy(PM)with space holder(SH)is a powerful technology used to produce porous Ti structures,it is here discussed its potential for the fabrication of medical devices from the perspectives of both design and *** most important parameters of the technique such as the size and shape of the initial metallic particles,the SH and binder type of materials,the compaction pressure of the green form,and in the sintering stage,the temperature,atmosphere,and time are reviewed according to the bibliography ***,the importance of the porosity and its types together with the influence of the mentioned parameters in the final porosity and,consequently,in the ultimate mechanical properties of the structure are ***,a few examples of the PM-SH application for the manufacturing of orthopedic implants are presented.

关键词： Powder metallurgy Space holder method Porous titanium structures Medical devices Stress shielding effect Porous materials permeability Interconnected porosity Porous bone substitute materials Open-cell titanium foams Sintering-dissolution technique

COMBINING SINGULAR SPECTRUM ANALYSIS AND PAR(p) STRUCTURES TO MODEL WIND SPEED TIME SERIES

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Journal of Systems Science & Complexity 2014年第1期27卷 29-46页

作者： MENEZES Moises Lima de SOUZA Reinaldo Castro PESSANHA jos francisco Moreira Department of Statistics Fluminense Federal University ( UFI~ Brazil. Email: moisesAima@msn.com.SOUZA Reinaldo Castro Electrical Engineering Department: Pontifical Catholic University of Rio de Janeiro (PUC-Rio) Brazil. Institute of Mathematics and Statistics State University of Rio de Janeiro (UERJ) Brazil.

Singular spectrum analysis （SSA） is a technique that decomposes a time series into a set of components, such as, trend, harmonics, and residuals. Leaving out the residual components and adding up the others, the time series can be smoothed. This procedure has been used to model Brazilian electricity consumption and flow series. The PAR（p）, periodic autoregressive models, has been broadly used in modelling energy series in Brazil. This paper presents an approach of this decomposition method, by fitting the PAR（p）, considering its multivariate version known as multivariate SSA （MSSA）. The method was applied to a vector of two wind speed series recorded at two locations in the Brazilian Northeast region. The obtained results, when compared to the univariate decomposition of each series, were far superior, showing that the spatial correlation between the two series were considered by MSSA decomposition stage.

关键词： MSSA periodic autoregressive model SSA wind speed series.

A numerical assessment of two geometries for reducing elbow erosion

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Particuology 2020年第2期18卷 117-133页

作者： Carlos Antonio Ribeiro Duarte francisco joséde Souza Diego Nei Venturi Martin Sommerfeld Department of Engineering Federal University of Goiás-Regional Catal(a)oAv.Dr.Lamartine Pinto de Avelar1120Catal(a)oGoiásBrazil School of Mechanical Engineering Federal University of Uberl(a)ndiaAv.Joāo Naves de(A)vila2121 Bloco 5PUberl(a)ndiaMinas GeraisBrazil Multiphase Flow Systems(MPS) Otto-von-Guericke-University MagdeburgZeppelinstraβe 1D-06130 Halle(Saale)Germany

Elbows in pneumatic conveying systems are normally prone to the erosive effects of conveyed *** are a number of solutions available to reduce such damage.A widely used geometric alternative for replacing the 90°elbow and reducing erosive wear is the plugged *** option,although less commonly used,is the vortex-chamber *** both cases,the effective reduction in erosion brought about is unclear,as it strongly depends on the operating *** present study assesses relative erosion among the plugged tee,vortex-chamber elbow,and standard elbow for a dilute gas-solid multiphase flow.A numerical model is employed to predict the penetration ratio and validated using experimental data for the plugged *** are run for the standard and vortex-chamber elbows and plugged tee under the same conditions to compare the mechanics involved and the relative erosion *** analysis uses variables relating to particle-wall interactions(impact angle,impact velocity,impact frequency)to illustrate the nature of the erosive process in each pipe *** general,the geometric configurations of both the plugged tee and vortex-chamber elbow promote changes in particle dynamics that reduce the rate of *** the basis of the relative erosion of the standard elbow,the plugged tee proves to be an interesting option in cases of a low mass loading,while the vortex-chamber elbow demonstrates its erosion reduction potential for higher mass loading ***,the advantages and disadvantages of each fitting are highlighted.

关键词： Relative erosion Plugged tee Erosion reduction Pipe fitting Computational fluid dynamics