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The Finite-dimensional Decomposition Property in Non-Archimedean Banach Spaces

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Acta Mathematica Sinica,English Series 2014年第11期30卷 1833-1845页

作者： Albert KUBZDELA Cristina perez-garcia Institute of Civil Engineering Poznań University of TechnologyUl.Piotrowo 561-138 PoznańPoland Department of Mathematics Facultad de CienciasUniversidad de CantabriaAvda.de los Castros s/n39071SantanderSpain

A non-Archimedean Banach space has the orthogonal finite-dimensional decomposition property（OFDDP） if it is the orthogonal direct sum of a sequence of finite-dimensional *** property has an influence in the non-Archimedean Grothendieck＇s approximation theory,where an open problem is the following： Let E be a non-Archimedean Banach space of countable type with the OFDDP and let D be a closed subspace of *** D have the OFDDP？ In this paper we give a negative answer to this question; we construct a Banach space of countable type with the OFDDP having a one-codimensional subspace without the *** we prove that,however,for certain classes of Banach spaces of countable type,the OFDDP is preserved by taking finite-codimensional subspaces.

关键词： Non-Archimedean Banach spaces finite-dimensional decomposition property orthogonal base

Attosecond twisted beams from high-order harmonicgeneration driven by optical vortices

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High Power Laser Science and Engineering 2017年第1期5卷 12-19页

作者： Carlos Hernandez-garcia Laura Rego Julio San roman Antonio Picon Luis Plaja Grupo de Investigacion en Aplicaciones del Laser y Fotonica Departamento de Fisica AplicadaUniversity of SalamancaE-37008SalamancaSpain Argonne National Laboratory Argonne1L 60439USA

Optical vortices are structures of the electromagnetic field with a spiral phase ramp about a point-phase singularity,carrying orbital angular momentum(OAM). Recently, OAM has been imprinted to short-wavelength radiation through high-order harmonic generation(HHG), leading to the emission of attosecond twisted beams in the extreme-ultraviolet(XUV) regime. We explore the details of the mapping of the driving vortex to its harmonic spectrum. In particular, we show that the geometry of the harmonic vortices is convoluted, arising from the superposition of the contribution from the short and long quantum paths responsible of HHG. Finally, we show how to take advantage of transverse phase-matching to select twisted attosecond beams with different spatiotemporal properties.

关键词： attosecond science extreme-ultraviolet vortices high harmonic generation orbital angular momentum twisted beams vortexbeams

Design of functional biomaterials as substrates for corneal endothelium tissue engineering

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Regenerative Biomaterials 2022年第1期9卷 1018-1036页

作者： Begona M.Bosch Elia Bosch-Rue Marina Perpiñan-Blasco roman A.perez Bioengineering Institute of Technology(BIT) Universitat Internacional de CatalunyaBarcelona 08195Spain Basic Sciences Department Universitat Internacional de CatalunyaBarcelona 08195Spain

Corneal endothelium defects are one of the leading causes of blindness *** actual treatment is transplantation,which requires the use of human cadaveric donors,but it faces several problems,such as global shortage of ***,new alternatives are being developed and,among them,cell therapy has gained interest in the last years due to its promising results in tissue ***,the direct administration of cells may sometimes have limited success due to the immune response,hence requiring the combination with extracellular mimicking *** this review,we present different methods to obtain corneal endothelial cells from diverse cell sources such as pluripotent or multipotent stem ***,we discuss different substrates in order to allow a correct implantation as a cell sheet and to promote an enhanced cell *** this reason,natural or synthetic matrixes that mimic the native environment have been *** matrixes have been optimized in terms of their physicochemical properties,such as stiffness,topography,composition and *** further enhance the matrixes properties,these can be tuned by incorporating certain molecules that can be delivered in a sustained manner in order to enhance biological ***,we elucidate future directions for corneal endothelial regeneration,such as 3D printing,in order to obtain patient-specific substrates.

关键词： corneal endothelium tissue engineering cell therapy biomaterials

CECRE:Supervision and Control of Spanish Renewable Energies in the Last 15 years

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Journal of Modern Power Systems and Clean Energy 2022年第2期10卷 269-276页

作者： Gema garcia Platero Mayte garcia Casado Marta perez garcia Paula Junco Madero David Alvira Baeza the Red Electrica de Espafia MaridSpain

From its commissioning in 2006 to the present,the Spanish Control Centre for Renewable Energies(CECRE)has been a worldwide pioneer and reference centre in the integration of renewable energies in the electrical *** the last 15 years,CECRE has allowed a high penetration of renewable energies in Spanish electrical system by means of the supervision and control of renewable facilities,while ensuring the power supply *** paper defines the bases of renewable en-ergy operation in CECRE and introduces forecasting systems for renewable ***,this paper describes the participation of renewable energies in balancing services and congestion ***,new challenges for Spanish transmission system operator(TSO)are presented for the integration of renewable energies along with the energy transition and decarbonization.

关键词： Balancing services controllability forecasting system observability Control Centre for Renewable Energies(CECRE) renewable energy photovoltaic(PV) wind.

Driving Factors for Forest Fire Occurrence in Durango State of Mexico:A Geospatial Perspective

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Chinese Geographical Science 2010年第6期20卷 491-497页

作者： Diana Avila-Flores Marin Pompa-garcia Xanat Antonio-Nemiga Dante A Rodriguez-Trejo Eduardo Vargas-perez Javier Santillan-perez Forestry Division University of Chapingo Faculty of Forestry Juarez University of the State of DurangoRio Papaloapan and Durango Blvd Faculty of Geography Autonomous University of Mexico StateCerro de Coatepec s/nCiudad Universitaria

Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management *** the driving factors and understanding the contribution of each factor are essential for the management of forest fire *** objective of this study is to identify variables that are spatially related to the occurrence and incidence of the forest fire in the State of Durango,*** this purpose,data from forest fire records for a five-year period were *** spatial correlations between forest fire occurrence and intensity of land use,susceptibility of vegetation,temperature,precipitation and slope were tested by Geographically Weighted Regression(GWR) method,under an Ordinary Least Square *** show that the spatial pattern of the forest fire in the study area is closely correlated with the intensity of land use,and land use change is one of the main explanatory *** addition,vegetation type and precipitation are also the main driving *** fitting model indicates obvious link between the *** fire was found to be the consequence of a particular combination of the environmental factors,and when these factors coexist with human activities,there is high probability of forest fire *** regulation of human activities is a key strategy for forest fire prevention.

关键词： forest fire Geographically Weighted Regression(GWR) land use forest management Durango State Mexico

Empowered Stakeholders: Female University Students’ Leadership During the COVID-19-Triggered On-campus Evictions in Canada and the United States

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International Journal of Disaster Risk Science 2021年第4期12卷 581-592页

作者： Haorui Wu Marla perez-Lugo Cecilio Ortiz garcia Frances Gonzalez Crespo Adriana Castillo Canada Research Chair in Resilience School of Social WorkDalhousie UniversityHalifaxNSB3H 4R2Canada Natural Hazards Center University of Colorado BoulderBoulderCO80309USA Department of Social Sciences University of Puerto Rico MayagüezMayagüezPR00682USA The RISE Network MayagüezPR00680USA

The study of disaster-specific leadership of female university students has been largely neglected,especially during on-campus emergency eviction and *** on the COVID-19-triggered,on-campus evictions across Canada and the United States,this cross-national partnership examined the out-of-province/state and international female university students’leadership during the entire eviction *** in-depth interviews,this study revealed the female university students’leadership behaviors during three stages:(1)pre-eviction:their self-preparedness formed an emotional foundation to support others;(2)peri-eviction:their attitude and leadership behavior enabled them to facilitate(psychologically and physically)their peers’eviction process;and(3)post-eviction:they continued to support their peers virtually and raised the general public’s awareness regarding the plight of vulnerable and marginalized *** article argues that the female university students’leadership that emerged during the eviction process became complementary to and even augmented the universities’official efforts and *** leadership represents empirical evidence that contributes to the existing literature on gender and leadership by demonstrating female youth as empowered stakeholders rather than as merely passive *** studies could develop detailed stratification of gender and age dimensions in order to portray a more comprehensive picture of the younger generation’s leadership in hazards and disaster research and practice.

关键词： Canada COVID-19 Female leadership Gender and disaster On-campus evictions United States University students

Preparation of Rod-like Aluminum Doped Zinc Oxide Powders by Sol-gel Technique Using Metal Chlorides and Acetylacetone Precursors

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Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1293-1297页

作者： KESHTKAR Javad VARGAS garcia Jorge Roberto GALAVIZ perez Jorge MARTINEZ TRINIDAD José Escuela Superior de Ingenieria Mecánica y Eléctrica Instituto Politécnico NacionalMéxico07738CDMXMéxico Escuela Superior de Ingenieria Quimica e Industrias Extractivas Instituto Politécnico NacionalMéxico07738CDMXMéxico Universidad Juárez Autònoma de Tabasco DivisiònAcadémica Multidisciplinaria de Jalpa de MéndezRibera AltaJalpa de MéndezTabasco86205México

Al-doped ZnO(AZO) powders were prepared by using metal chloride precursors and the sol-gel technique. IR peaks observed at 1590 cm-1 and 1620 cm-1indicated the formation of metal chelate as a consequence of the addition of acetylacetone to the metal chloride solution. TG-DSC analysis of the AZO gels confirmed the formation of metal chelate as evidenced by the development of several weight loss peaks accompanied by the introduction of new endothermic peaks. The resulting AZO gels were annealed at 500, 600, and 800 ℃ to study the effect of annealing temperature. XRD and SEM results showed that crystallization of AZO gels takes place around 600 ℃. Hexagonal wurtzite structure was identified as the main phase for all the samples. In addition, small shift of the XRD(002) peak coupled with XPS results from the AZO powders confirmed the successful doping of the ZnO powders. Micron sized rod-like AZO powders were uniform in dimension and morphology and remained stable even at 800 ℃.

关键词： aluminum doped ZnO rod-like metal chloride sol gel acetylacetone

Crystalline retinopathy and optical coherence tomography angiography:new insights in pathogenesis

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Annals of Eye Science 2020年第3期5卷 19-29页

作者： Jaclyn L.Kovach Diley perez garcia Bascom Palmer Eye Institute Miller School of MedicineUniversity of MiamiNaplesFLUSA

Optical coherence tomography angiography(OCTA)is a fast,non-invasive imaging modality that provides detailed information on retinal and choroidal vascular flow and macular *** offers an accurate three-dimensional view of the individual retinal vascular plexuses and the choriocapillaris which facilitates the detection of the microvascular abnormalities in a variety of macular *** perfusion indices(vessel density and flow index)are valuable parameters evaluated by OCTA that allow a quantitative interpretation of changes in the retinal vasculature that can reflect the severity of *** retinopathy encompasses a group of conditions whose distinctive feature is the presence of retinal crystals often located in the posterior *** crystalline retinopathies also demonstrate retinal vascular abnormalities as *** that the OCTA is a novel imaging modality and crystalline retinopathies are relatively rare conditions,there are currently few reports of OCTA findings associated with crystalline *** advent of OCTA allows visualization of vascular and structural changes in crystalline retinopathies that are unique and cannot be appreciated on other imaging modalities,including fluorescein angiography(FA).This article reviews novel OCTA findings which provide new insights in the pathogenesis of crystalline retinopathies,including Bietti crystalline retinopathy,talc retinopathy,macular telangiectasia type 2,tamoxifen retinopathy,and Sjögren-Larsson Syndrome maculopathy.

关键词： Crystalline retinopathy optical coherence tomography angiography(OCTA) multimodal imaging

Recurrent anal fistulae:Limited surgery supported by stem cells

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World Journal of Gastroenterology 2015年第11期21卷 3330-3336页

作者： Damian garcia-Olmo Hector Guadalajara Ines Rubio-perez Maria Dolores Herreros Paloma de-la-Quintana Mariano garcia-Arranz Hospital Fundación Jimenez Díaz Colorectal Surgery Unit University Hospital Fundación Jiménez Díaz Colorectal Surgery Unit La Paz University Hospital Cell Therapy Laboratory University Hospital Fundación Jiménez Díaz

AIM:To study the results of stem-cell therapy under a Compassionate-use Program for patients with recurrent anal ***:Under controlled circumstances,and approved by European and Spanish laws,a Compassionate-use Program allows the use of stem-cell therapy for patients with very complex anal *** had previously undergone multiple surgical interventions that had failed to resolve the fistulae,and presented symptomatic *** intervention consisted of limited surgery(with closure of the internal opening),followed by local implant of stem cells in the fistula-tract *** expanded adipose-derived stem cells were the main cell type selected for *** first evaluation was performed on the 8th postoperative week;outcome was classified as response or partial *** one year after the intervention confirmed if complete healing of the fistula was ***:Ten patients(8 male)with highly recurrent and complex fistulae were treated(mean age:49years,range:28-76 years).Seven cases were nonCrohn’s fistulae,and three were Crohn’s-associated *** surgical attempts ranged from 3to *** patients presented with preoperative incontinence(Wexner scores of 12 and 13 points).After the intervention,six patients showed clinical response on the 8th postoperative week,with a complete cessation of suppuration from the *** patients presented a partial response,with an evident decrease in suppuration.A year later,six patients(60%)remained healed,with complete reepithelization of the external *** Wexner Scores were 0 in six *** two patients with previous incontinence improved their scores from12 to 8 points and from 13 to 5 *** adverse reactions or complications related to stem-cell therapy were reported during the study ***:Stem cells are safe and useful for treating anal *** can be achieved in severe cases,sparing fecal incontinence risk,and impr

关键词： Adipose-derived stem cells Cell therapy Compassion