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Neural Regeneration Research 2021年第8期16卷 1564-1565页

作者： Paulina Troncoso-Escudero Claudio Hetz rene l.vidal Biomedical Neuroscience Institute Faculty of MedicineUniversity of ChileSantiagoChile Center for Geroscience Brain Health and MetabolismSantiagoChile Program of Cellular and Molecular Biology Institute of Biomedical SciencesUniversity of ChileSantiagoChile Center for Integrative Biology Faculty of SciencesUniversity MayorChile Buck Institute for Research on Aging NovatoCAUSA

Huntington's disease(HD) is an inherited autosomal dominant neurodegenerative disorder characterized by the development of adult-onset motor dysfunction,psychiatric disturbances and intellectual *** is associated with an expansion of CAG repeat sequence in the huntingtin gene(Htt).Exon 1 of Htt normally contains between 6 to 35 CAG repeats,whereas in patients affected with HD it contains more than 40 trinucleotides.

关键词： Huntington Therapeutic stasis

High pressure responsive luminescence of flexible Eu^(3+) doped PVDF fibrous mats

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Journal of Materials Science & Technology 2021年第7期66卷 103-111页

作者： Carlos Hernandez San tosh K.Gupta Jose P.Zuniga Jorge vidal rene Galvan Hector Guzman lilian Chavez Karen lozano Yuanbing Mao Department Department of Chemistry University of Texas Rio Grande Valley1201 West University DriveEdinburgTX 78539USA Radiochemistry Division Bhabha Atomic Research CentreTrombayMumbai400085USA Department of Electrical Engineering University of Texas Rio Grande ValleyEdinburgTX 78539USA Department of Chemistry Illinois Institute of Technology3105 South Dearborn StreetChicagoIL 60616USA

Exploring lanthanide doped materials and their high-pressure optical properties is important from the perspective of designing pressure sensors, piezoelectric materials, scintillators, and optoelectronic devices, just to mention a few. Understanding the high-pressure optical properties of polymeric fibrous mats provides significant advantages in terms of flexibility, tunability, facile processability, and malleability. In this work, we have developed flexible polyvinylidene difluoride(PVDF) fibrous mats doped with an Eu^(3+) source of Eu(NO_(3))_(3)·5H_(2)O(EN-PF) or Eu_(2)(SO_(4))_(3)(ES-PF) by a Forcespinning■ method. Microstructural analysis of these two systems indicates that Eu(NO_(3))_(3)·5H_(2)O and Eu_(2)(SO_(4))_(3) are homogeneously distributed and dispersed into the PVDF matrix. Fiber formation promotes a β-phase PVDF. Eu^(3+) doping increases the β-phase. Its fraction is larger for the ES-PF mats. To understand their high-pressure optical properties, their photoluminescence spectra have been taken at various pressures up to 58 GPa in a diamond anvil cell. High-pressure luminescence illustrates a clear change in asymmetry ratio, peak intensity, peak breadth, color coordinate, and color temperature of Eu^(3+) ions from both EN-PF and ES-PF with a different extent of changes. Specifically, Eu^(3+) ions in the ES-PF mats switch from asymmetric to symmetric environment as pressure increases. Those in the EN-PF mats present symmetric environment for all tested pressures. Both of the Eu^(3+) doped PVDF systems present irreversible changes. Therefore,the EN-PF fibrous mats present an opportunity to make pressure induced red-orange-yellow tunable phosphors for multifunctional applications.

关键词： Polyvinylidene difluoride Europium Fiber High pressure luminescence

Hybrid Triboelectric-Electromagnetic Nanogenerators for Mechanical Energy Harvesting:A Review

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Nano-Micro letters 2021年第12期13卷 163-220页

作者： Joao V.vidal Vladislav Slabov Andrei l.Kholkin Marco P.Soares dos Santos Department of Physics and CICECO-Aveiro Institute of Materials University of Aveiro3810-193 AveiroPortugal Department of Physics and I3N University of Aveiro3810-193 AveiroPortugal laboratory of Functional low-Dimensional Structures National University of Science and Technology MISISMoscowRussia Department of Mechanical Engineering Centre for Mechanical Technology and Automation(TEMA)University of Aveiro3810-193 AveiroPortugal

Motion-driven electromagnetictriboelectric energy generators(E-TENGs) hold a Hybrid triboelectric-electromagnetic generators C A Bgreat potential to provide higher voltages,higher currents and wider operating bandwidths than Cantilever generators1 μm both electromagnetic and triboelectric generators Rotating generatorsSliding generators standing alone. Therefore,they are promising solutions to autonomously supply a broad range of Flexible blade generators Magnetoelectric highly sophisticated devices. This paper provides generators a thorough review focused on major recent breaklinear generators Multidimensional generators throughs in the area of electromagnetic-triboelectric vibrational energy harvesting. A detailed Pendulum generators analysis was conducted on various architectures including rotational,pendulum,linear,sliding,cantilever,flexible blade,multidimensional and 1 cm magnetoelectric,and the following hybrid technologies. They enable highly e cient ways to harvest electric energy from many forms of vibrational,rotational,biomechanical,wave,wind and thermal sources,among others. Open-circuit voltages up to 75 V,short-circuit currents up to 60 mA and instantaneous power up to 144 mW were already achieved by these nanogenerators. Their transduction mechanisms,including proposed models to make intelligible the involved physical phenomena,are also overviewed here. A comprehensive analysis was performed to compare their respective construction designs,external excitations and electric outputs. The results highlight the potential of hybrid E-TENGs to convert unused mechanical motion into electric energy for both large-and small-scale ***,this paper proposes future research directions toward optimization of energy conversion e ciency,power management,durability and stability,packaging,energy storage,operation input,research of transduction mechanisms,quantitative standardization,system integration,miniaturization and multi-energy hybrid cells.

关键词： E-TENG Hybrid triboelectric-electromagnetic Nanogenerators Energy harvesting

SYNTHESIS AND PROPERTIES OF HOMOPOlYMER AND COPOlYMERS OBTAINED FROM 1-OCTADECENE WITH ZIRCONOCENE CATAlYSTS

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Chinese Journal of Polymer Science 2000年第3期18卷 249-254页

作者： Raul Quijada Juan l.Guevara rene Rojas Franco M.Rabagliati Departamento de Ingenieria Quimica Facultad de Ciencias Fisicasy MatematicasUniversidad de ChileCasilla 2777SantiagoChile Departamento Ciencias Quimicas Facultad Quimicay BiologiaUniversidad de Santiago de ChileCasilla 40SantiagoChile

Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be *** metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-Me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization *** show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest *** lower temperatures(≤30℃)thedifferences are *** the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-Me_(2)Si(Ind)_(2)ZrCl_(2)were *** results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NMR analysis shows that thecomposition of the copolymerization products depends on the catalytic *** obtained with rac-Me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer *** analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization *** homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-Me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not *** type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower *** measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关键词： Homopolymerization Copolymerization Metallocene Catalytic activity Poly-l-octadecene

Isla San Pedro Nolasco as a late Miocene intrusive record at the eastern margin of the Gulf of California:Insights from geological,geochemical and geochronological studies

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Geoscience Frontiers 2022年第3期13卷 100-114页

作者： l.A.Velderrain-Rojas J.R.vidal-Solano l.M.Alva-Valdivia R.Vega-Granillo M.lópez-Martinez Departamento de Geología División de Ciencias Exactas y NaturalesUniversidad de SonoraC.P.83000 HermosilloSonoraMexico laboratorio de Paleomagnetismo Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación CientíficaC.P.04510 MéxicoD.F.Mexico Departamento de Geología División de Ciencias de la TierraCentro de Investigación Científica y de Educación Superior de EnsenadaBaja CaliforniaMexico

Isla San Pedro Nolasco(ISPN)is a structural high bounded by inactive dextral oblique-slip faults in the east-central part of the Gulf of California rift zone and is composed of intrusive rocks not exposed on other Gulf of California *** we present the reconnaissance results from geological mapping,as well as first geochemical and geochronological data for the ISPN intrusive *** intrusive rocks compose a sheet-like body of intermediate and felsic composition intruded by an intermediate and acidic dike *** intrusive rocks(host and dikes)range in age from ca.9 Ma to 10 Ma(^(40)Ar/^(39)Ar)and show a hydrous ferromagnesian mineral association(amphibole and biotite)with a calc-alkalic and transitional *** hydrated mineralogical association has not been recognized in the coeval rocks along the onshore western margin of the North American plate(coastal Sonora).However,such hydrous mineralogical association is found in the coeval rift transitional volcanic rocks from the Baja California Microplate at Santa Rosalía and Bahía de losÁngeles–Bahía de lasÁ*** ISPN continental block,at least 40 km long,has been pulled apart by transtensional faulting of the late Miocene Gulf of California shear zone before the westward migration of the North America-Pacific plate boundary at ca.3–2 ***,ISPN became isolated as an island during the late Miocene flooding of the Gulf of California seaway.

关键词： PAC-NAM plate boundary Gulf of California Intrusive rocks Isla San Pedro Nolasco

Direct quantification of topological protection in symmetry-protected photonic edge states at telecom wavelengths

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light(Science & Applications) 2021年第1期10卷 5-11页

作者： Sonakshi Arora Thomas Bauer rene Barczyk Ewold Verhagen l.Kuipers Kavli Institute of Nanoscience Delft University of Technology2600 GA DelftThe Netherlands Center for Nanophotonics AMOLFScience Park 1041098 XG AmsterdamThe Netherlands

Topological on-chip photonics based on tailored photonic crystals(PhCs)that emulate quantum valley-Hall effeas has recently gained widespread interest owing to its promise of robust unidirectional transport of classical and quantum *** present a direct quantitative evaluation of topological photonic edge eigenstates and their transport properties in the telecom wavelength range using phase-resolved near-field optical *** visualizing the detailed sub-wavelength structure of these modes propagating along the interface between two topologically non-trivial mirror-symmetric lattices allows us to map their dispersion relation and differentiate between the contributions of several higher-order Bloch *** probing of forward-and backward-propagating modes as defined by their phase velocities enables direct quantification of topological *** near-field propagation in controlled defects allows us to extract upper limits of topological protection in on-chip photonic systems in comparison with conventional PhC *** find that protected edge states are two orders of magnitude more robust than modes of conventional PhC *** direct experimental quantification of topological robustness comprises a crucial step toward the application of topologically protected guiding in integrated photonics,allowing for unprecedented error-free photonic quantum networks。

关键词： protected quantum symmetry

High efficiency gas-liquid separation system for pumped wells

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Petroleum 2019年第2期5卷 178-182页

作者： l.Enrique Ortiz-vidal Marcel C.Barbosa Oscar M.H.Rodriguez Industrial Multiphase Flow laboratory(lEMI) Mechanical Engineering DepartmentS~ao Carlos School of EngineeringUniversity of S~ao Paulo(USP)13563-120Sao CarlosSPBrazil

Gas-liquid separation is a very common process in industrial plants,where often high Efficiency of Gas Separation(EGS)is *** the upstream oil industry,gas separation is also crucial for the proper operation of Electrical Submergible Pumps(ESP).Recent studies report the excellent performance of a gravitational separator known as Inverted-Shroud separator(IS-separator).laboratory results indicate that this kind of separator can achieve total gas separation for a wide range of operation conditions under continuous two-phase *** original intent is to use the IS-separator for downhole gas separation in oil production ***,by account of its simple design and relatively compact size,it may be suitable for using in industrial *** this paper,we present the IS-separator in details,including geometry characteristics and *** equipment performance is also *** addition,the challenges related to the deep understanding of the gas separation process inside the IS-separator and the possible practical solutions are outlined.

关键词： separation pumped details

Anti-inflammatory properties of the short-chain fatty acids acetate and propionate:A study with relevance to inflammatory bowel disease

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World Journal of Gastroenterology 2007年第20期13卷 2826-2832页

作者： Sofia Tedelind Fredrik Westberg Martin Kjerrulf Alexander vidal Department of Molecular Pharmacology AstraZeneca R&DMlndalSweden

AIM： To compare the anti-inflammatory properties of butyrate with two other SCFAs, namely acetate and propionate, which have less well-documented effects on inflammation. METHODS： The effect of SCFAs on cytokine release from human neutrophils was studied with EHSA. SCFA- dependent modulation of NF-κB reporter activity was assessed in the human colon adenocarcinoma cell line, Colo320DM. Finally, the effect of SCFAs on gene expression and cytokine release, measured with RT-PCR and ElISA, respectively, was studied in mouse colon organ cultures established from colitic mice. RESUlTS： Acetate, propionate and butyrate at 30 mmol/l decreased lPS-stimulated TNFα release from neutrophils, without affecting Il-8 protein release. All SCFAs dose dependently inhibited NF-κB reporter activity in Colo320DM cells. Propionate dose-dependently suppressed Il-6 mRNA and protein release from colon organ cultures and comparative studies revealed that propionate and butyrate at 30 mmol/l caused a strong inhibition of immune-related gene expression, whereas acetate was less effective. A similar inhibition was achieved with the proteasome inhibitor MG-132, but not the p38 MAPK inhibitor SB203580. All SCFAs decreased Il-6 protein release from organ cultures. CONClUSION： In the present study propionate and butyrate were equipotent, whereas acetate was less effective, at suppressing NF-κB reporter activity, immune-related gene expression and cytokine release in vitro. Our findings suggest that propionate and acetate, in addition to butyrate, could be useful in the treatment of inflammatory disorders, including IBD.

关键词： Neutrophils Epithelial cells Colitis Infla- mmation Short-chain fatty acids Acetate Propionate Butyrate NF-KB Cytokines

Experimental control of optical helicity in nanophotonics

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light(Science & Applications) 2014年第1期3卷 166-172页

作者： Nora Tischler Ivan Fernandez-Corbaton Xavier Zambrana-Puyalto Alexander Minovich Xavier vidal Mathieu l Juan Gabriel Molina-Terriza ARC Centre for Engineered Quantum Systems Department of Physics&AstronomyMacquarie UniversitySydneyNSW 2109Australia Department of Physics&Astronomy Macquarie UniversitySydneyNSW 2109Australia Nonlinear Physics Centre and Centre for Ultrahigh-bandwidth Devices for Optical Systems(CUDOS) Research School of Physics and EngineeringThe Australian National UniversityCanberraACT 0200Australia

An analysis of light–matter interactions based on symmetries can provide valuable insight,particularly because it reveals which quantities are conserved and which ones can be transformed within a physical *** this context,helicity can be a useful addition to more commonly considered observables such as angular *** question arises how to treat helicity,the projection of the total angular momentum onto the linear momentum direction,in practical *** this paper,we put forward a simple but versatile experimental treatment of *** then apply the proposed method to the scattering of light by isolated cylindrical nanoapertures in a gold *** allows us to study the helicity transformation taking place during the interaction of focused light with the *** particular,we observe from the transmitted light that the scaling of the helicity transformed component with the aperture size is very different to the direct helicity component.

关键词： helicity nanoaperture nanophotonics optics symmetry

The importance of the bite angle of metal(Ⅲ) salen catalysts in the sequestration of CO_(2) with epoxides in mild conditions

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Green Chemical Engineering 2022年第2期3卷 180-187页

作者： Anna vidal-lopez Sergio Posada-Perez Miquel Sola Valerio D'Elia Albert Poater Institut de Quimica Computacional i Catalisi and Departament de Quimica Universitat de GironaC/Maria Aurelia Capmany6917003GironaCataloniaSpain Department of Chemistry Universitat Autonoma de BarcelonaCerdanyola del VallesCatalonia08193Spain Department of Materials Science and Engineering School of Molecular Science and EngineeringVidyasirimedhi Institute of Science and Technology(VISTEC)21210PayupnaiWang ChanThailand

located in the middle of the fever to solve the problem of CO_(2)emissions in the environment,CO_(2)sequestration by reaction with epoxides is one of the key tools,as it not only fixes CO_(2),but also makes it functional by leading to cyclic ***,the results are focused specifically on the formation of cyclic organic carbonates catalyzed by metal-salen complexes,previously achieved with yttrium and scandium,that are compared with those of analogous complexes containing metals from the first transition series,such as cobalt or *** functional theory(DFT)calculations allow to determine whether this switch of metals will be feasible and provide the basis for instigating future experimental efforts in this *** calculations analyzing the structure and electronics of the catalysts allow us to give not only a clear picture of whether these catalysts will be efficient,but also allow us to assess which metal center is the most convenient and/or whether the catalytic reaction will occur under mild *** buried volume calculations with the SambVca packages shed light on the different catalytic pockets of monometallic first row transition metals *** III salen *** predictive catalysis results show that the bite O-M-O angle plays an essential role in the catalysis.

关键词： CO_(2)fixation Salen catalyst CO_(2)functionalization Cyclic carbonate DFT calculations Predictive catalysis