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BIOcELL 2022年第8期46卷 1867-1873页

作者： ana m.cárdenas I.GALLO FERNANDO D.mARENGO centro Interdisciplinario de Neurociencia de Valparaíso Facultad de CienciasUniversidad de ValparaísoValparaíso2360102Chile Instituto de Fisiología Biología Molecular y NeurocienciasCONICET.Departamento de Fisiología y Biología Molecular y CelularFacultad de Ciencias Exactas y Naturales Universidad de Buenos AiresBuenos Aires1428Argentina

The cortical actin network is a mesh of filaments distributed beneath the plasmalemma that dynam.cally reacts in response to *** dynam.c network of cortical filaments,together with motor myosin partners,adjusts the plasmalemma tension,organizes membrane protein m.crodomains,remodels the cell surface and drives vesicle motion in order to fine-tune exocytosis,endocytosis and recycling of secretory *** this review,we discuss how these m.chanisms work in secretory cells.

关键词： cortical actin Neuroendocrine cell chromaffin cell Exocytosis Endocytosis

Assessment and monitoring Damage by <i>coraebus florentinus</i>(coleoptera: Buprestidae) in mediterranean Oak Forests

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Open Journal of Ecology 2018年第5期8卷 324-338页

作者： ana m. cárdenas Patricia Gallardo Department of Zoology University of Córdoba Córdoba Spain

coraebus florentinus (Herbst) is a wood borer beetle that damages the most abundant Quercus species making up the mediterranean forests. Damage is due to the feeding activity of the larvae which cuts the sap flow into the branch where it develops, drying it. In the last decades, the geographical range and the damage records of this species have expanded northwardly as a result of the climate global change since warmer conditions favor higher reproduction and quicker development of this species. On this paper, historical series of data after ten years evaluating damages by c. florentinus in Hornachuelos Natural Park (Southern Spain) are analyzed under the perspective of the environmental temperature increase linked to the global climate change. The assessment was done between 2007 and 2017, in two sampling plots of mediterranean mixed-oak forests where holm and cork oaks are the predominant tree species. Results show that the infestation levels of this species at the beginning of the assessment period were higher than those described previously in the nineties and that they increased progressively during the monitoring time. The results also agree with the expansion of its distribution areas noticed in other areas of Europe. The foreseeable rising of damages of c. florentinus is discussed, at greater scale, under the perspective of future scenery of environmental warming and oaks decaying by losing fitness due to higher soil aridity.

关键词： Buprestidae coleoptera coraebus florentinus Damage mediterranean monitoring Oak Forests

Ni/Al Intermetallics Plasma Transferred Arc Processing

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材料热处理学报 2004年第05B期25卷 948-951页

作者： Veronica A. B. Almeida ana Sofia c. m. D'Oliveira master student - PIPE Federal University of Parana Curitiba/BrazilMechanical Engineering Department Federal University of Parana Curitiba/Brazil

In-situ alloy development during surface processing allows for a limitless materials selection to protect components exposed to severe service conditions. In fact surface alloying offers the possibility to strengthen surface components with alloys that would not be possible to process otherwise. This work used Plasma transferred arc (PTA) hardfacing for surface alloying. Different amounts of aluminium powder, 5-25%, were added to a Ni based superalloy, from Hastealloy c family, in the atomized form. The mixture was homogeneized in a ball mill and PTA deposited on carbon steel substrate. The influence of different processing parameters on the final surface alloy was evaluated as current intensity and depositing velocity were varied. coatings were characterized by optical and scanning electronic m.croscopy, X-ray diffraction and Vickers m.crohardness profiles, under a 500g load. Results showed that PTA hardfacing is an adequate surface alloying. For the conditions tested increasing hardness was obtained by solid solution for the lower amounts of Al added and due to the new intermetallic phases for the richer Al mixture.

关键词： PTA合金等离子转移电弧 Ni/Al金属互化物表面处理

Thermal properties and high-temperature ablation of high-entropy (Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating on graphite substrate

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Journal of Advanced ceram.cs 2024年第8期13卷 1268-1281页

作者： ana c.Feltrin Daniel Hedman Farid Akhtar Division of materials Science Lulea University of TechnologyLulea 97187Sweden center for multidimensional carbon materials(cmcm) Institute for Basic Science(IBS)Ulsan 44919Republic of Korea

An entropy-stabilized multicomponent ultrahigh-temperature ceram.c(UHTc)coating,(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2),on a graphite substrate was in-situ sintered by spark plasma sintering(SPs)from.constituent transition metal diboride ***(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating had a hardness of 31.2±2.1 GPa and resisted 36.9 GPa of stress before delamination,as observed at the *** temperature-dependent thermal properties of the multicomponent diboride(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) were obtained by molecular dynam.cs(mD)simulations driven by a m.chine learning force field(mLFF)trained on density functional theory(DFT)*** thermal conductivity,density,heat capacity,and coefficient of thermal expansion obtained by the mD simulations were used in time-dependent thermal stress finite element model(FEm)*** low thermal conductivity(m^(-1)·K^(-1))of the multicomponent diboride coupled with its similar coefficient of thermal expansion to that of graphite indicated that stresses of less than 10 GPa were generated at the interface at high temperatures,and therefore,the coating was m.chanically resistant to the thermal stress induced during *** experiments at 220℃ showed that the multicomponent diboride coating was resistant to thermal stresses with no visible cracking or *** ablation m.chanisms were m.chanical denudation and evaporation of B_(2)O_(5) and light V-Ti oxides,which caused a decrease in the mass and thickness of the coating and resulted in mass and linear ablation rates of-0.51 mg·s^(-1) and -1.38μm·s^(-1),respectively,after 60 *** findings demonstrated the thermal and m.chanical stability of multicomponent entropy-stabilized diborides as coatings for carbon materials in engineering components under extreme environments.

关键词： entropy-stabilized diborides ultrahigh temperature ceram.cs molecular dynam.cs(mD)simulations density functional theory(DFT) ablation properties

Symmetry and Transitive Properties of monohedral f-triangulations of the Riemannian Sphere

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Acta mathematica Sinica,English Series 2009年第10期25卷 1609-1616页

作者： ana m.BREDA J.m.SIGARRETA Department of mathematics University of Aveiro Facultad de matematicas Universidad Autonoma de Guerrero

Here we give the complete description of the symmetry group and transitive properties of the set of all of monohedral triangulations of the Riemannian sphere by f-tilings. We shall also show that each monohedral f-tiling of the Riemannian sphere can be seen, up to a spherical isometry, as the singular set of a spherical isometric folding.

关键词： isometric folding monohedral tiling graphs combinatoric

Bendable tube-shaped supercapacitor based on reduced graphene oxide and Prussian blue coated carbon fiber yarns for energy storage

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Journal of Energy chemistry 2018年第3期27卷 866-873页

作者： mohd.Khalid ana m.B.Honorato Department of m.cromolecular Science and Engineering Case Western Reserve University

carbon fiber yarns（cFY） are promising as a new type of flexible building blocks for the construction of flexible architectures for the energy storage applications. The main hurdle with cFY is how to make them high energy and power capable by using econom.cally and environmentally viable materials. Here,we report reduced graphene oxide（r GO） and Prussian blue（PB） coated cFY, derived from a facile electrochem.cal process at room temperature for supercapacitor electrodes. The PB coated cFY and r GO coated cFY electrodes exhibit the excellent gravimetric capacitance of 339 F/g and 160.2 F/g, respectively, in aqueous Kcl electrolyte in three-electrode cell configuration. When we coupled these electrodes inside the flexible plastic tube and separated by the electrolyte wet filter paper in order to construct flexible architecture, the resulting device delivers excellent specific energy of 52.1 Wh/kg and 26.5 Wh/kg with offering specific power of 3100 W/kg and 14400 W/kg respectively, under a wide operating potential of1.8 V with excellent rate capability. The device shows high tolerance towards bending, and retained its efficiency to the capacitance after being bent at an angle of 360° for 200 bending cycles.

关键词： carbon fiber yarns Bendable supercapacitor Energy density Power density

Degradation of duloxetine: Identification of transformation products by UHPLc-ESI(+)-HRmS/mS,in silico toxicity and wastewater analysis

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Journal of Environmental Sciences 2019年第8期31卷 113-123页

作者： Rodrigo A.Osawa ana P.carvalho Olinda c.monteiro m.conceicao Oliveira m.Helena Florêncio centro de Quím.ca e Bioquím.ca Faculdade de Ciências Universidade de Lisboa Laboratório de FTIcR e Espectrometria de massa Estrutural Faculdade de Ciências Universidade de Lisboa centro de Quím.ca Estrutural Instituto Superior Técnico Universidade de Lisboa

Duloxetine(DUL), an antidepressant drug, has been detected in surface water and wastewater effluents, however, there is little information on the formation of its transformation products(TPs). In this work, hydrolysis, photodegradation(UV irradiation) and chlorination experiments were performed on spiked distillated water, under controlled experimental conditions to simulate abiotic processes that can occur in the environment and wastewater treatment plants(WWTPs). Eleven TPs, nine from reaction with UV light and two from.chlorine contact, were formed and detected by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry, and nine of them had their chem.cal structures elucidated upon analyses of their fragmentation patterns in mS/mS spectra. The formation and degradation of the TPs were observed. The parent compound was completely degraded after30 min in photodegradation and after 24 hr in chlorination. Almost all TPs were completely degraded in the experiments. The ecotoxicity and mutagenicity of the TPs were predicted based on several in silico models and it was found that a few of these products presented more ecotoxicity than DUL itself and six TPs showed positive mutagenicity. Finally, wastewater samples were analyzed and DUL and one TP, possibly formed by chlorination process, were detected in the effluent, which showed that WWTP not only did not remove DUL, but also formed a TP.

关键词： High resolution mass spectrometry Duloxetine Degradation processes Transformation products Wastewater analysis In silico toxicity

The Influence of High Temperature Exposure on the Wear Performance of a Ni Based Alloy PTA coating

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材料热处理学报 2004年第5期25卷 152-156页

作者： Karin Graf ana Sofia c.m. d'OIiveira m.chanical Department of Universidade Federal do Parana Curitiba BrazilMechanical Department of Universidade Federal do Parana Curitiba Brazil

Degradation phenomena like wear and corrosion, may have their effects accelerated as components operate at high temperature. The aim of this work is to make an indirect evaluation of the influence of high temperature exposure on wear behavior of Ni coatings. A Ni-cr-mo-W alloy, was deposited with Plasma Transferred Arc (PTA) process. An indirect approach based on the Ahrrenius relationship was used to evaluated long time exposures at high temperatures. To simulate longer exposures at lower temperatures, coatings were exposed to higher temperatures for the same time interval. So coatings were soaked in an air furnace at 650°c, 1000°c and 1200°c. metal/metal wear behavior was evaluated by pin-on-disc tests. Pins were removed from the coatings by eletrodischarge m.chining and rubbed against a Vc31 quenched and tempered tool steel. Two sets of wear tests were run at 2m/s, for different loads (0.5, 1.0, 2.0 and 3.0Kg) and for different sliding distances (120, 720, 1080, 1440 and 1800m).coatings characterization was done by scanning electronic m.croscopy and Vickers m.crohardness. Results showed as temperature is increased, coatings wear performance is altered, and this is associated with m.crostructural changes.

关键词：磨损 Ni合金 PTA 高温曝露

Impact of tropospheric modelling on GNSS vertical precision:an empirical analysis based on a local active network

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International Journal of Digital Earth 2018年第9期11卷 880-896页

作者： mªSelmira Garrido m.clara de Lacy ana mªRojas Department of cartographic Geodetic and Photogrammetric EngineeringUniversity of JaénJaenSpain center for Advanced Studies in Earth Sciences University of JaénJaenSpain Research group RNm282–m.crogeodesia Jaén University of JaénJaenSpain

The troposphere affects Global Navigation Satellite System(GNSS)signals due to the variability of the refractive *** delay is a function of the satellite elevation angle and the altitude of the GNSS receiver and depends on the atmospheric *** the residual tropospheric delay is not modelled carefully a bias error will occur in the vertical *** order to analyse the precise altimetric positioning based on a local active network,four scenarios in Southern Spain with different topographical,environmental,and meteorological conditions are presented,considering both favourable and non-favourable *** use of surface meteorological observations allows us to take into account the tropospheric conditions instead of a standard atmosphere,but introduces a residual tropospheric bias which reduces the accuracy of precise GNSS ***,with short observation times it is recommended not to estimate troposphere parameters,but to use an a priori model together with the standard *** results confirm that it is possible to achieve centimetre-scale vertical accuracy and precision with real time kinematic positioning even with large elevation differences with respect to the nearest reference *** numerical results may be taken into consideration for improving the altimetric configuration of the local active network.

关键词： Altimetry GNSS meteorological data active network tropospheric refraction

Tropical dendrochronology applied to invasive tree species in the Brazilian Atlantic Forest

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Journal of Forestry Research 2021年第1期32卷 91-101页

作者： carolina Nogueira Xavier Daniela Granato-Souza ana carolina m.c.Barbosa JoséReinaldo moreira da Silva Forest Sciences Department Federal University of Lavras(UFLA)C.P.3037Lavras 37200-000Brazil Department of Geosciences University of ArkansasFayettevilleAR 72701USA

The Atlantic Forest is one of the largest and most biodiverse rainforests of South America but anthropogenic activities are drastically changing these *** invasion of alien or exotic species is one of the greatest threats to *** are few studies of invasive species in tropical Brazilian *** research examines growth and ecological aspects of Syzygium.cumini and clitoria fairchildiana,two invasive tree species in the Pedra Branca State Park,an Atlantic Forest remnant in southeastern *** species were successfully dated,indicating an average age of 58 and 31 years,respectively.A positive relationship between growth and precipitation of the previous growing season suggests an ecological adaptive strategy,which could be facilitating their invasion into the *** growth diameter curves indicate slow and fast growth rates for *** and ***,*** release episodes detected in the tree rings indicate increased anthropogenic disturbances over the last 50 years.

关键词： Atlantic Forest biome Invasive species Protected areas Tree rings