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Effects of dielectric stoichiometry on the photoluminescence properties of encapsulated WSe2 monolayers

Nano Research 2018年第3期11卷 1399-1414页

作者： javier martfn-sanchez Antonio Mariscal Marta De Luca Aitana Tarazaga Martin-Luengo Georg Gramse Alma Halilovic Rosalia Serna Alberta Bonanni Ilaria Zardo Rinaldo Trotta Armando Rastelli Institute of Semiconductor and Solid State Physics Johannes Kepler University Linz Altenbergerstrasse 69 A-4040 Linz Austria Laser Processing Group Instituto de Optica CSIC C/Serrano 121 28006 Madrid Spain Department of Physics University of Basel Klingelbergstrasse 82 4056 Basel Switzerland Institute for Biophysics Johannes Kepler University Linz Gruberstrasse 40 A-4020 Linz Austria

Two-dimensional transition metal dichalcogenide semiconductors have emerged as promising candidates for optoelectronic devices with unprecedented properties and ultra-compact footprints. However, the high sensitivity of atomically thin materials to the surrounding dielectric media imposes severe limitations on their practical applicability. Hence, to enable the effective integration of these materials in devices, the development of reliable encapsulation procedures that preserve their physical properties is required. Here, the excitonic photoluminescence （at room temperature and 10 K） is assessed on mechanically exfoliated WSe2 monolayer flakes encapsulated with SiOx and AlxOy layers by means of chemical and physical deposition techniques. Conformal coating on untreated and non- functionalized flakes is successfully achieved by all the techniques examined, with the exception of atomic layer deposition, for which a cluster-like oxide coating is formed. No significant compositional or strain state changes in the flakes are detected upon encapsulation, independently of the technique adopted. Remarkably, our results show that the optical emission of the flakes is strongly influenced by the stoichiometry quality of the encapsulating oxide. When the encapsulation is carried out with slightly sub-stoichiometric oxides, two remarkable phenomena are observed. First, dominant trion （charged exciton） photoluminescence is detected at room temperature, revealing a clear electrical doping of the monolayers. Second, a strong decrease in the optical emission of the monolayers is observed, and attributed to non-radiative recombination processes and/or carrier transfer from the flake to the oxide. Power- and temperature-dependent photoluminescence measurements further confirm that stoichiometric oxides obtained by physical deposition lead to a successful encapsulation, opening a promising route for the development of integrated two-dimensional devices.

关键词： two dimensional （2D）materials,dielectric encapsulation,transition metaldichalcogenides,semiconductors,photoluminescence,WSe2

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Genomic selection in plant breeding:Key factors shaping two decades of progress

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Molecular Plant 2024年第4期17卷 552-578页

作者： Admas Alemu Johanna Astrand Osval A.Montesinos-López Julio Isidro y sanchez javier Fernandez-Gónzalez Wuletaw Tadesse Ramesh R.Vetukuri Anders S.Carlsson Alf Ceplitis JoséCrossa Rodomiro Ortiz Aakash Chawade Department of Plant Breeding Swedish University of Agricultural SciencesAlnarpSweden Lantmannen Lantbruk SvalövSweden Facultad de Telematica University de ColimaColimaColima 28040Mexico Centro de Biotecnología y Genómica de Plantas(CBGP UPM-INIA)Universidad Politécnica de Madrid(UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria(INIA)Campus de Montegancedo-UPM28223 MadridSpain International Center for Agricultural Research in the Dry Areas(ICARDA) RabatMorocco International Maize and Wheat Improvement Center(CIMMYT) Km 45Carretera México-VeracruzTexcocoMéxico 52640Mexico

Genomic selection,the application of genomic prediction(GP)models to select candidate individuals,has significantly advanced in the past two decades,effectively accelerating genetic gains in plant breeding.This article provides a holistic overview of key factors that have influenced GP in plant breeding during this period.We delved into the pivotal roles of training population size and genetic diversity,and their relationship with the breeding population,in determining GP accuracy.Special emphasis was placed on optimizing training population size.We explored its benefits and the associated diminishing returns beyond an optimum size.This was done while considering the balance between resource allocation and maximizing prediction accuracy through current optimization algorithms.The density and distribution of single-nucleotide polymorphisms,level of linkage disequilibrium,genetic complexity,trait heritability,statistical machine-learning methods,and non-additive effects are the other vital factors.Using wheat,maize,and potato as examples,we summarize the effect of these factors on the accuracy of GP for various traits.The search for high accuracy in GP—theoretically reaching one when using the Pearson’s correlation as a metric—is an active research area as yet far from optimal for various traits.We hypothesize that with ultra-high sizes of genotypic and phenotypic datasets,effective training population optimization methods and support from other omics approaches(transcriptomics,metabolomics and proteomics)coupled with deep-learning algorithms could overcome the boundaries of current limitations to achieve the highest possible prediction accuracy,making genomic selection an effective tool in plant breeding.

关键词： genomic selection genetic gain genomic prediction optimization deep learning training population optimization

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Contributions to data transmission at critical moments on unmanned aerial vehicles

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Chinese Journal of Aeronautics 2023年第8期36卷 247-257页

作者： Jose Enrique RODRIGUEZ David SEGURADO Manuel sanchez Jose javier MARTINEZ Rafael GONZALEZ National Institute of Aerospace Technology Madrid 28850Spain Department of Computer Science University of AlcalaAlcala de HenaresMadrid 28054Spain

As for unmanned aircraft, the knowledge of the aircraft performance is directly related with the navigation, guidance, and control system programming. Therefore, the measured data in each phase of the flight must be sufficiently precise to obtain a good characterization of aircraft.This article proposes new methods of sending information to ground, which make it possible to know the aircraft behavior accurately, and for this purpose, four contributions have been made for ALO(Avión Ligero de Observación, Spanish acronym for Light Observation Aircraft). Currently, the characterization is based on data obtained at ten samples per second, insufficient to acquire detailed knowledge of what happened during the whole flight of an aircraft. As a result of these contributions, many more samples per second of accelerations and angular velocities are obtained at the most critical moments of the flight, such as takeoff or landing. Among the improvements included are data compression techniques, providing references to locate the measured data in time and identifying labels of each parameter.

关键词： Critical moments Data transmission Datacompression tech-niques Radio-modem Recommended Standard 232(RS-232) Unmannedaerial vehicle

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Taxonomy-based differences in feeding guilds of fish

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Current Zoology 2020年第1期66卷 51-56页

作者： javier sanchez-HERNANDEZ Departamento de Zooloxla Xenetica e Antropoloxfa FlsicaFacultade de BioloxfaUniversidade de Santiago de CompostelaCampus Vida s/nSantiago de CompostelaEspana

It has been taken for granted that feeding guilds and behavior in animals are linked to the taxonomic relatedness of species,but empirical evidence supporting such relationship is virtually missing.To examine the importance of taxonomy on trophic ecology,I here present the first well-resolved dietary taxonomy analysis based on feeding guilds(predation,herbivory,and filtering)among families and genera within the fish order Perciformes.Taxonomic relatedness in feeding did not vary with ecosystem dimension(marine vs.freshwater).Although predation dominates among Perciformes fishes,this study shows that in most cases taxonomic units(family or genus)are composed by species with several feeding guilds.Related species are more similar in feeding compared with species that are taxonomically more distant demonstrating that there is a greater variation of feeding guilds within families than genera.Thus,there is no consistency in feeding guilds between family-and genus-level taxonomy.This study provides empirical support for the notion that genera are more informative than families,underlining that family-level taxonomy should be avoided to infer feeding habits of fish species at finer taxonomic resolution.Thus,the choice of taxonomic resolution(family or genus level)in ecological studies is key to avoid information loss and misleading results.I conclude that high-rank taxonomic units(i.e.,above the generic level)are not appropriate to test research hypotheses about the feeding of fish.

关键词： aquatic systems clades FishBase global datasets taxonomic sufficiency trophic ecology

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Colorectal cancer screening and surveillance in patients with inflammatory bowel disease in 2021

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World Journal of Gastroenterology 2022年第5期28卷 502-516页

作者： Jose Maria Huguet Luis Ferrer-Barceló Patrícia Suárez Eva sanchez Jose David Prieto Victor Garcia javier Sempere Department of Digestive Disease General University Hospital of ValenciaValencia 46014Spain

The detection of dysplasia in patients with inflammatory bowel disease(IBD)continues to be important given the increased risk of colorectal cancer in this population.Therefore,in 2017,we performed a review and update of the recommendations for the management and follow-up of patients with IBD based on the clinical practice guidelines of various scientific societies.The present manuscript focuses on new aspects of the detection,follow-up,and management of dysplasia according to the latest studies and recommendations.While chromoendoscopy with targeted biopsy continues to be the technique of choice for the screening and detection of dysplasia in IBD,the associated difficulties mean that it is now being compared with other techniques(virtual chromoendoscopy),which yield similar results with less technical difficulties.Furthermore,the emergence of new endoscopy techniques that are still being researched but seem promising(e.g.,confocal laser endomicroscopy and full-spectrum endoscopy),together with the development of devices that improve endoscopic visualization(e.g.,Endocuff Vision),lead us to believe that these approaches can revolutionize the screening and follow-up of dysplasia in patients with IBD.Nevertheless,further studies are warranted to define the optimal follow-up strategy in this patient population.

关键词： Colitis surveillance Colitis screening Chromoendoscopy Colorectal cancer Inflammatory bowel disease Ulcerative colitis

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The cold-induced factor CBF3 mediates root stem cell activity,regeneration,and developmental responses to cold

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Plant Communications 2023年第6期4卷 197-211页

作者： Pablo Perez-Garcia Ornella Pucciariello Alvaro sanchez-Corrionero javier Cabrera Cristina del Barrio Juan Carlos del Pozo Mariano Perales Krzysztof Wabnik Miguel A.Moreno-Risueno Centro de Biotecnologíay Genómica de Plantas(Universidad Politécnica de Madrid(UPM)–Instituto Nacional de Investigacióny Tecnología Agraria y Alimentaria–CSIC(INIA-CSIC)) MadridSpain

Plant growth and development involve the specification and regeneration of stem cell niches(SCNs).Although plants are exposed to disparate environmental conditions,how environmental cues affect developmental programs and stem cells is not well understood.Root stem cells are accommodated in meristems in SCNs around the quiescent center(QC),which maintains their activity.Using a combination of genetics and confocal microscopy to trace morphological defects and correlate them with changes in gene expression and protein levels,we show that the cold-induced transcription factor(TF)C-REPEAT BINDING FACTOR 3(CBF3),which has previously been associated with cold acclimation,regulates root development,stem cell activity,and regeneration.CBF3 is integrated into the SHORT-ROOT(SHR)regulatory network,forming a feedback loop that maintains SHR expression.CBF3 is primarily expressed in the root endodermis,whereas the CBF3 protein is localized to other meristematic tissues,including root SCNs.Complementation of cbf3-1 using a wild-type CBF3 gene and a CBF3 fusion with reduced mobility show that CBF3 movement capacity is required for SCN patterning and regulates root growth.Notably,cold induces CBF3,affecting QC activity.Furthermore,exposure to moderate cold around 10℃–12℃promotes root regeneration and QC respecification in a CBF3-dependent manner during the recuperation period.By contrast,CBF3 does not appear to regulate stem cell survival,which has been associated with recuperation from more acute cold(-4℃).We propose a role for CBF3 in mediating the molecular interrelationships among the cold response,stem cell activity,and development.

关键词： stem cells regeneration organ patterning protein movement cell fate low temperature

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基于计算缩放的光滑粒子水动力学方法模拟飞机油箱剧烈晃动问题

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Acta Mechanica Sinica 2023年第2期39卷 39-48页

作者： Calderon-sanchez javier Martinez-Carrascal Jon Gonzalez Leo Miguel CEHINAV Model Basin ETSI NavalesUniversidad Politécnica de MadridMadrid28040Spain

大型民用飞机的机翼设计用于承受从大气阵风到湍流到着陆冲击的各种载荷,机翼是需要进一步研究的重要结构.改进机翼设计的主要方法之一是分析晃动对承载液体的柔性机翼状结构动力学的阻尼效应.这将通过开发实验装置来实现,该装置将有助... 详细信息

大型民用飞机的机翼设计用于承受从大气阵风到湍流到着陆冲击的各种载荷,机翼是需要进一步研究的重要结构.改进机翼设计的主要方法之一是分析晃动对承载液体的柔性机翼状结构动力学的阻尼效应.这将通过开发实验装置来实现,该装置将有助于建立和再现涉及物理领域的数值模型.因此,本工作的目的是使用数值方法光滑粒子流体动力学(SPH)作为主要数值工具,分析晃动在降低飞机结构设计载荷方面的影响.本研究中的一个关键因素是对比例实验的需求,这是评估计算工具是否能够准确近似不同比例的注册测量值的必要步骤.为此,建立了一个垂直振动水槽的数值模型,该模型是一个完全耦合的流固耦合问题.该结构通过质量-弹簧-阻尼器系统建模,对于内部流体,使用δ-SPH方法.特别是,研究了两个开放性问题:第一个问题是,当储罐的初始加速度是标准重力值的十倍时,重力对阻尼和能量耗散现象的影响程度;第二种问题旨在确认,当根据量纲分析对问题参数进行缩放时,SPH方程正确地再现了缩放定律.

关键词： SPH Sloshing Gravity Computational scaling

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Prevalence of meeting 24-Hour Movement Guidelines from pre-school to adolescence: A systematic review and meta-analysis including 387,437 participants and 23 countries

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Journal of Sport and Health Science 2022年第4期11卷 427-437页

作者： Miguel Angel Tapia-Serrano javier Sevil-Serrano Pedro Antonio sanchez-Miguel Jose Francisco Lopez-Gil Mark STremblay Antonio Garcıa-Hermoso Department of Didactics of Musical Plastic and Body ExpressionFaculty of Teaching TrainingUniversity of ExtremaduraAvenida de la UniversidadS/NCaceres 10071Spain Department of Physical Activity and Sport Faculty of Sport ScienceUniversity of Murcia(UM)San Javier 30720Spain Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario(CHEO)Research InstituteOttawaON K1H 8L1Canada Navarrabiomed Public University of Navarra(UPNA)Health Research Institute of Navarra(IdiSNA)Navarra Hospital Complex(CHN)Pamplona 310008Spaia

Background:Meeting the 24-Hour Movement Guidelines(physical activity,screen time,and sleep duration) has been associated with positive health indicators.However,there are no previous meta-analyses that have examined the overall adherence to the 24-Hour Movement Guidelines from pre-school to adolescence across the world.Therefore,the main purpose of this systematic review and meta-analysis was to examine the overall(non)adherence to the 24-Hour Movement Guidelines among preschoolers,children,and adolescents worldwide.Methods:Four electronic databases(MEDLINE,Scopus,Web of Science,and Cochrane Database of Systematic Reviews) were searched for quantitative studies published in Spanish and English between January 2016 and May 2021.Studies that were conducted with apparently healthy participants and reported the overall(non)adherence to the 24-Hour Movement Guidelines in preschoolers and/or children and/or adolescents were included.Results:Sixty-three studies comprising 387,437 individuals(51% girls) aged 3-18 years from 23 countries were included.Overall,7.12%(95%confidence interval(95%CI):6.45%-7.78%) of youth met all three 24-Hour Movement Guidelines,and 19.21%(95%CI:16.73%-21.69%)met none of the 3 recommendations.Concerning sex,adherence to all recommendations was significantly lower in girls(3.75%,95%CI:3.23%-4.27%) than in boys(6.89%,95%CI:5.89%-7.89%)(p <0.001).However,there were no sex differences regarding adherence to any of the 3 individual recommendations(girls,15.66%,95%CI:8.40%-22.92%;boys,12.95%,95%CI:6.57%-19.33%).In terms of age group,adherence to the 3 recommendations was 11.26%(95%CI:8.68%-13.84%),10.31%(95%CI:7.49%-13.12%),and 2.68%(95%CI:1.78%-3.58%) in preschoolers,children,and adolescents,respectively.Conversely,8.81%(95%CI:5.97%-11.64%) of preschoolers,15.57%(95%CI:11.60%-19.54%) of children,and 28.59%(95%CI:22.42%-34.75%) of adolescents did not meet any of the recommendations.South America was the region with the lowest adherence(all:2.93%;none:31.72%).Overall adherence to the 24-Hour Movement

关键词： Exercise Lifestyle Movement behaviors Sedentary behaviors Youth

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MEC-based architecture for interoperable and trustworthy internet of moving things

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Digital Communications and Networks 2023年第1期9卷 270-279页

作者： Jesus sanchez-Gomez Rafael Marin-Perez Ramon sanchez-Iborra Miguel Angel Zamora Department of Information and Communications Engineering University of MurciaMurciaSpain Odin Solutions S.L. MurciaSpain University Center of Defense San Javier Air Force BaseMurciaSpain

The expansion of the Internet of Moving Things(IoMT)leads to limitless and continuous working playgrounds exploited by highly dynamic end devices.This requires the adoption of multi-Radio Access Technologies(RATs)-based strategies to provide IoMT units with ubiquitous connectivity.To this end,the development of secure bootstrapping and authentication mechanisms is necessary to permit the secure operation of end devices.Given the transmission and power limitations of these elements,current cryptographic solutions do not address these stringent requirements.For that reason,in the study we present a Multi-Access Edge Computing(MEC)-based endto-end architecture that enables an efficient and secure authentication and key agreement between end devices and network servers over heterogeneous resource-limited networks such as the Low Power Wide Area Networks(LPWANs).Our proposal is based on the Authentication,Authorization,and Accounting(AAA)architecture and the recent Internet Engineering Task Force initiatives Static Context Header Compression and Low-Overhead CoAP-EAP.The results obtained from experimental tests reveal the validity of the proposal as it enables constrained IoMT devices to gain IPv6 connectivity as well as performs end-to-end secure authentication with notable reliability and controlled latency.

关键词： Internet of moving things LPWAN Authentication LO-CoAP-EAP SCHC

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Transcriptional Programs Related to Phytochrome A Function in Arabidopsis Seed Germination

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Molecular Plant 2013年第4期6卷 1261-1273页

作者： Silvia E. Ibarra Gabriela Auge Rodolfo A. sanchez javier F. Botto IFEVA Facultad de Agronomfa Universidad de Buenos Aires y Consejo Nacional de Investigaciones Cientificas y Tecnicas Av. San Martin 4453 C1417DSECiudad de Buenos Aires Argentina

In Arabidopsis seeds, germination is promoted only by phytochromes, principally phytochrome B （phyB） and phytochrome A （phyA）. Despite the abundant information concerning the molecular basis of phyB signaling downstream of PIF1/PIL5, the signaling network inducing germination by phyA is poorly known. Here, we describe the influence of phyA on the transcriptome of Arabidopsis seeds when germination is induced by a far-red （FR） pulse. The expression of 11% of the genome was significantly regulated by phyA. Most of the genes were up-regulated and the changes noted late （i.e. 5 h after a FR pulse）, whereas changes in down-regulated genes were more abundant earlier （i.e. 0.5 h after a FR pulse）. Auxin- and GA-associated elements were overrepresented in the genes that were modified by phyA. A significant number of genes whose expression was affected by phyA had not been previously reported to be dependent on PIL5. Among them, homozygotic mutant seeds of MYB66, a SAUR-like protein, PIN7, and GASA4 showed an impaired promo- tion of germination by phyA. Natural variation at the transcriptional level was found in early signaling and GA metabolic genes, but not in ABA metabolic and expansin genes between Columbia and Landsberg erecta accessions. Although phyA and phyB/PIL5 signaling pathways share some molecular components, our data suggest that phyA signaling is partially independent of PIL5 when germination is promoted by very low fluences of light.

关键词： transcriptome germination light Arabidopsis seeds PIF1/PIL5 phytochrome A （phyA） phytochrome B （phyB）.

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