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Devitrification process in rapidly solidified Al-Ni-Cu-Nd metallic glass

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Journal of Central South University of Technology 2003年第3期10卷 163-167页

作者：肖于德黎文献 D.Jacovkis N.Clavaguera m.T.Clavaguera-mora J.rodriguez-Viejo College of materials Science and Engineering Central South University Changsha 410083 China Grup de Fisica de Materials I Departament de FisicaUniversitat Autonoma de Barcelona 08193 Bellaterra Spain Fisica de l'Estat Solid Facultat de Fisica Universitat de BarcelonaDiagonal 647 08028 Barcelona Spain College of materials Science and Engineering Central South University Changsha 410083 China Grup de Fisica de materials I Departament de Fisica Universitat Autonoma de Barcelona 08193 Bellaterra Spain Fisica de l'Estat Solid Facultat de Fisica Universitat de Barcelona Diagonal 647 08028 Barcelona Spain)

In the present study, rapidly solidified ribbons of Al87 Ni7Cu3 Nd3 metallic glass was prepared by usingmelt spinning. Devitrification process of the totally amorphous ribbons was investigated by high temperature X-raydiffraction analysis, combining with differential scanning calorimetry, under continuous and isothermal heating re-gime. The X-ray diffraction intensity and full width at the half maximum (FWHm) were analyzed to investigate theincrease of crystallized amount and growth of α-Al crystal particles. The results show that under continuous heatingregime, the metallic glass devitrifies via two main stages: primary crystallization, resulting in two-phase mixture ofα-Al plus residual amorphous phase, and secondary crystallization, corresponding to rapid precipitation of some in-ter-metallic phases in the form of dispersion or eutectic mixture. Under isothermal heating regime, only Al crystalprecipitates from the Al-rich amorphous matrix at low temperature, and when heating at 280 ℃ only Al crystal pre-cipitates within a short time, and then Al8 Cu4 Nd forms, followed by Al3 Ni, in the residual amorphous phase. Whenheating at higher temperature or for longer time, Aln Nd3 forms, the amorphous phase disappears, and the ribbonsdevelop into polycrystalline morphologies with multiply phase mixture of a-Al, Al8 Cu4 Nd, Al3 Ni, and Al11 Nd3.

关键词： rapid solidification Al-rich amorphous alloy devitrification process phase transformation

Plant cover as an estimator of above-ground biomass in semi-arid woody vegetation in Northeast Patagonia,Argentina

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Journal of Arid Land 2021年第9期13卷 918-933页

作者： Laura B rodriguez Silvia S TORRES ROBLES marcelo F ARTURI Juan m ZEBERIO Andrés C H GRAND Néstor I GASPARRI National University of Río Negro Atlantic HeadquartersCenter for Environmental Studies from Norpatagonia(CEANPa)Viedma 8500Argentina National Council of Scientific and Technical Research(CONICET) Viedma 8500Argentina Ecological and Environmental Systems Research Laboratory(LISEA) National University of La PlataLa Plata 1900Argentina National Institute of Agricultural Technology(INTA) AER PatagonesCarmen de Patagones 8504Argentina Institute of Regional Ecology(IER) National University of Tucumán(UNT)-National Council of Scientific and Technical Research(CONICET)Tucumán 4000Argentina Faculty of Natural Sciences and miguel Lillo Institute National University of Tucumán(UNT)Yerba Buena 4107Argentina

The quantification of carbon storage in vegetation biomass is a crucial factor in the estimation and mitigation of CO2 ***,arid and semi-arid regions are considered an important carbon ***,they have received limited attention and,therefore,it should be a priority to develop tools to quantify biomass at the local and regional *** plant variables,such as stem diameter and crown area,were reported to be good predictors of individual plant ***-level variables,such as plant cover and mean height,are also easy-to-measure estimators of above-ground biomass(AGB)in dry *** this study,we estimated the AGB in semi-arid woody vegetation in Northeast Patagonia,*** evaluated whether the AGB at the stand level can be estimated based on plant cover and to what extent the estimation accuracy can be improved by the inclusion of other field-measured structure *** also evaluated whether remote sensing technologies can be used to reliably estimate and map the regional mean *** this purpose,we analyzed the relationships between field-measured woody vegetation structure variables and AGB as well as LANDSAT Tm-derived *** obtained a model-based ratio estimate of regional mean AGB and its standard *** plant cover allowed us to obtain a reliable estimation of local AGB,and no better fit was attained by the inclusion of other structure *** stand-level plant cover ranged between 18.7%and 95.2%and AGB between about 2.0 and 70.8 mg/hm^(2).AGB based on total plant cover was well estimated from LANDSAT Tm bands 2 and 3,which facilitated a model-based ratio estimate of the regional mean AGB(approximately 12.0 mg/hm^(2))and its sampling error(about 30.0%).The mean AGB of woody vegetation can greatly contribute to carbon storage in semi-arid ***,plant cover estimation by remote sensing images could be used to obtain regional estimates and map biomass,as well as to assess and monitor the i

关键词： above-ground biomass shrublands ratio estimation carbon storage remote sensing Patagonia

Homotypic Vacuole Fusion Requires VTI11 and Is Regulated by Phosphoinositides

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molecular Plant 2014年第6期7卷 1026-1040页

作者： Sang Won Han maria Fernanda rodriguez-Welsh marcela Rojas-Pierce Department of Plant and microbial Biology North Carolina State University Raleigh NC 27695 USA

most plant cells contain a large central vacuole that is essential to maintain cellular turgor. We report a new mutant allele of VTI11 that implicates the SNARE protein VTI11 in homotypic fusion of protein storage and lytic vacuoles. Fusion of the multiple vacuoles present in vtill mutants could be induced by treatment with Wortmannin and LY294002, which are inhibitors of Phosphatidylinositol 3-Kinase （PI3K）. We provide evidence that Phosphatidylinositol 3-Phosphate （Ptdlns（3）P） regulates vacuole fusion in vtill mutants, and that fusion of these vacuoles requires intact microtubules and actin filaments. Finally, we show that Wortmannin also induced the fusion of guard cell vacuoles in fava beans, where vacuoles are naturally fragmented after ABA-induced stomata closure. These results suggest a ubiquitous role of phosphoinositides in vacuole fusion, both during the development of the large central vacuole and during the dynamic vacuole remodeling that occurs as part of stomata movements.

关键词： vacuole SNARE phosphoinositides membrane fusion Wortmannin.

OTB-morph:One-time Biometrics via morphing

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machine Intelligence Research 2023年第6期20卷 855-871页

作者： mahdi Ghafourian Julian Fierrez Ruben Vera-rodriguez Aythami morales Ignacio Serna Biometrics and Data Pattern Analytics Laboratory(BiDA Lab) Universidad Autonoma de MadridMadrid28049Spain

Cancelable biometrics are a group of techniques to transform the input biometric to an irreversible feature intentionally using a transformation function and usually a key in order to provide security and privacy in biometric recognition *** transformation is repeatable enabling subsequent biometric *** paper introduces a new idea to be exploited as a transformation function for cancelable biometrics aimed at protecting templates against iterative optimization *** proposed scheme is based on time-varying keys(random biometrics in our case)and morphing *** experimental implementation of the proposed scheme is given for face *** results confirm that the proposed approach is able to withstand leakage attacks while improving the recognition performance.

关键词： Biometrics face recognition template protection morphing security

Silk-ELR co-recombinamer covered stents obtained by electrospinning

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Regenerative Biomaterials 2019年第1期6卷 21-28页

作者： m.Putzu F.Causa manuel Parente Israel Gonza´lez de Torre J.C.rodriguez-Cabello P.A.Netti Dipartimento di Ingegneria Chimica dei Materiali e della Produzione Industriale(DICMAPI)University“Federico II”Piazzale Tecchio 8080125 NaplesItaly Interdisciplinary Research Centre on Biomaterials(CRIB) University of Naples Federico IIPiazzale Tecchio 8080125 NapoliItaly Center for Advanced Biomaterials for Health Care@CRIB Istituto Italiano di TecnologiaLargo Barsanti e Matteucci 5380125 NapoliItaly Conic Vascular via Carlo Maderno 236901 LuganoSwitzerland Technical Proteins NanoBioTechnology S.L. Edificio CTTAPaseo de Belen9A47011 ValladolidSpain Networking Research Center on Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)ValladolidSpain Bioforge Lab University of ValladolidEdificio LUCIAPaseo de Belen1947011 ValladolidSpain

In the field of tissue engineering the choice of materials is of great importance given the possibility to use biocompatible polymers produced by means of biotechnology.A large number of synthetic and natural materials have been used to this purpose and processed into scaffolds using Electrospinning *** materials that could be used for the fabrication of scaffold and degradable membranes,natural polymers such as collagen,elastin or fibroin offer the possibility to design structures strictly similar to the extracellular matrix(ECm).Biotechnology and genetic engineering made possible the advent of a new class of biopolymers called protein-based *** example is represented by the silk-elastin-proteins that combine the elasticity and resilience of elastin with the high tensile strength of silk-fibroin and display engineered bioactive *** this work,we use electrospinning technique to produce a fibrous scaffold made of the corecombinamer *** fibres have been characterized from the morphological point of *** and morphology have been explored using Scanning Electron microscopy.A thorough study regarding the influence of Voltage,flow rate and distance have been carried out to determine the appropriate parameters to obtain the fibrous mats without defects and with a good distribution of *** has also been in vitro *** the first time we use the co-recombinamer Silk-ELR for the fabrication of a 2.5 angioplasty balloon *** structure could be useful as a coated scaffold for the regeneration of intima layer of vessels.

关键词： electrospinning silk elastin-like-recombinamers tissue engineering

Novel Fast Operating moving Coil Actuator with Compensation Coil for HVDC Circuit Breakers

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CSEE Journal of Power and Energy Systems 2021年第5期7卷 1041-1050页

作者： Boyuan Yin Xianwu Zeng John F.Eastham Damian Vilchis-rodriguez Xiaoze Pei Department of Electronic&Electrical Engineering.University of Bath.Bath.United Kingdom Department of mechanical Engineering University of Bath.Bath.United Kingdom. Power and Energy Division School of Electrical and Electronic EngineeringThe University of ManchesterManchester M139PLUnited Kingdom.

DC circuit breakers are major enabling components for multi-terminal HVDC *** key design targets are operating speed and *** paper proposes a novel moving coil actuator using a compensation coil topology to operate mechanical circuit *** topology aims to significantly improve the magnetic field saturation and reduce the system inductance,so that the operating speed is *** possible connection methods for the compensation coils are proposed and analyzed using finite element modeling,ensuing simulation results are compared and *** operating speed of the moving coil actuator with compensation coils is significantly improved compared with the original moving coil *** moving coil actuator with compensation coils can open a distance of 5 mm within 2.8 ms and the peak efficiency is 47%.

关键词： Compensation coil DC circuit breaker HVDC mechanical circuit breaker moving coil actuator

Parametrization of mean Radiative Properties of Optically Thin Steady-State Plasmas and Applications

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Communications in Computational Physics 2014年第8期16卷 612-631页

作者： R.rodriguez G.Espinosa J.m.Gil J.G.Rubiano m.A.mendoza P.martel E.minguez Departmento de Fisica Universidad de Las Palmas de Gran Canaria35017Spain. Instituto de Fusion Nuclear Universidad Politecnica de Madrid28006MadridSpain.

Plasma radiative properties play a pivotal role both in nuclear fusion and *** are essential to analyze and explain experiments or observations and also in radiative-hydrodynamics *** computation requires the generation of large atomic databases and the calculation,by solving a set of rate equations,of a huge number of atomic level populations in wide ranges of plasma *** facts make that,for example,radiative-hydrodynamics in-line simulations be almost *** has lead to develop analytical expressions based on the parametrization of radiative ***,most of them are accurate only for coronal or local thermodynamic *** this work we present a code for the parametrization of plasma radiative properties of mono-component plasmas,in terms of plasma density and temperature,such as radiative power loss,the Planck and Rosseland mean opacities and the average ionization,which is valid for steady-state optically thin plasmas in wide ranges of plasma densities and ***,we also present some applications of this parametrization such as the analysis of the optical depth and radiative character of plasmas,the use to perform diagnostics of the electron temperature,the determination of mean radiative properties for multicomponent plasmas and the analysis of radiative cooling instabilities in some kind of experiments on high-energy density laboratory ***,to ease the use of the code for the parametrization,this one has been integrated in a user interface and brief comments about it are presented.

关键词： Parametrization of plasma radiative properties and applications steady-state collisional-radiative model optically thin mono-and multi-component plasmas.

A Direct Link between Abscisic Acid Sensing and the Chromatin-Remodeling ATPase BRAHmA via Core ABA Signaling Pathway ComDonents

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molecular Plant 2016年第1期9卷 136-147页

作者： marta Peirats-Llobet Soon-Ki Han miguel Gonzalez-Guzman Cheol Woong Jeong Lesia rodriguez Borja Belda-Palazon Doris Wagner Pedro L. rodriguez Instituto de Biologia molecular y Celular de Plantas Consejo Superior de Investigaciones Cientfficas-Universidad Politecnica de Valencia 46022 Valencia Spain Department of Biology University of Pennsylvania Philadelphia PA 19104 USA These authors contributed equally to this article

Optimal response to drought is critical for plant survival and will affect biodiversity and crop performance during climate change. mitotically heritable epigenetic or dynamic chromatin state changes have been implicated in the plant response to the drought stress hormone abscisic acid （ABA）. The Arabidopsis SWI/SNF chromatin-remodeling ATPase BRAHmA （BRm） modulates response to ABA by preventing pre- mature activation of stress response pathways during germination. We show that core ABA signaling pathway components physically interact with BRm and post-translationally modify BRm by phosphoryla- tion/dephosphorylation. Genetic evidence suggests that BRm acts downstream of SnRK2.2/2.3 kinases, and biochemical studies identified phosphorylation sites in the C-terminal region of BRm at SnRK2 target sites that are evolutionarUy conserved. Finally, the phosphomimetic BRms17s^D S1762D mutant displays ABA hypersensitivity. Prior studies showed that BRm resides at target loci in the ABA pathway in the presence and absence of the stimulus, but is only active in the absence of ABA. Our data suggest that SnRK2- dependent phosphorylation of BRm leads to its inhibition, and PP2CA-mediated dephosphorylation of BRm restores the ability of BRm to repress ABA response. These findings point to the presence of a rapid phosphorylation-based switch to control BRm activity; this property could be potentially harnessed to improve drought tolerance in plants.

关键词： abscisic acid hormone signaling chromatin remodeling

Paclitaxel-loaded hollow-poly（4-vinylpyridine） nano- particles enhance drug chemotherapeutic efficacy in lung and breast cancer cell lines

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Nano Research 2017年第3期10卷 856-875页

作者： Rafael Contreras-Caceres maria C. Leiva Raul Ortiz Amelia Diaz Gloria Perazzoli miguel A.Casado-rodriguez Consolacion melguizo Jose m. Baeyens Juan m. Lopez-Romero Jose Prados Department of Organic Chemistry Faculty of Science University of Mdlaga 29071 Malaga Spain Institute of Biopathology and Regenerative medicine (IBImER) Center of Biomedical Research (CIBM) University of Granada 18100 Granada Spain Department of Anatomy and Embryology Faculty of Medicine University of Granada 18071 Granada Spain Biosanitary Institute of Granada (IBS. GRANADA) SAS-Universidad de Granada 18014 Granada Spain Department of Health Science University of Jaen 23071 Jadn Spain Department of Pharmacology Institute of Neuroscience Biomedical Research Center (CIBM) University of Granada 18100 Granada Spain

Paclitaxel （PTX）, one of the most effective cytotoxins for the treatment of breast and lung cancer, is limited by its severe side effects and low tumor selectivity. In this work hollow-poly（4-vinylpyridine）（hollow-p4VP） nanoparticles （NPs） have been used for the first time to generate PTX@p4VP NPs, employing a novel technique in which a gold core in the center of the NP is further oxidized to produce the hollow structure into which PTX molecules can be incorporated. The hollow-p4VP NPs exhibit good physicochemical properties and displayed excellent biocompatibility when tested on blood （no hemolysis） and cell cultures （no cytotoxicity）. Interestingly, PTX@p4VP NPs significantly increased PTX cytotoxicity in human lung （A-549） and breast （mCF-7） cancer cells with a significant reduction of PTX ICs0 （from 5.9 to 3.6 nm in A-549 and from 13.75 to 4.71 nm in mCF-7）. In addition, PTX@p4VP caused a decrease in volume of A-549 and mCF-7 multicellular tumor spheroids （mTS）, an in vitro system that mimics in vivo tumors, in comparison to free PTX. This increased antitumoral activity is accompanied by efficient cell internalization and increased apoptosis, especially in lung cancer mTS. Our results offer the first evidence that hollow- p4VP NPs can improve the antitumoral activity of PTX. This system can be used as a new nanoplatform to overcome the limitations of current breast and lung cancer treatments.

关键词： paclitaxel poly(4-vinylpyridine)(p4VP) nanoparticles lung cancer breast cancer cytotoxicity multicellular tumorspheroids