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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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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 *** 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 *** relatedness in feeding did not vary with ecosystem dimension(marine ***).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 *** 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 ***,there is no consistency in feeding guilds between family-and genus-level *** 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 ***,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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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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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 *** 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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Back-table surgery pancreas allograft for transplantation:Implications in complications

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World Journal of Transplantation 2021年第1期11卷 1-6页

作者： javier Briceño Juan Manuel Sánchez-Hidalgo Alvaro Arjona-sanchez Department of General and Digestive Surgery Reina Sofia University HospitalCordoba 14004Spain

To describe the main aspects of back-table surgery in pancreatic graft and the problems arising from poor ***-table surgery for pancreatic graft is a complex,meticulous and laborious technique on which the success of implant surgery and perioperative results *** technique can be described in the following steps:Preparation of the sterile table,ex-situ inspection of the pancreasspleen block,management of the duodenum,identification of the bile duct,preparation of the portal vein,preparation of the own graft arteries and anastomosis to the arterial graft,spleen management and graft preservation prior to implantation in the recipient.A careful inspection of the pancreas-spleen block should be *** is important to identify the stump of the main bile duct,the portal vein cuff,and the arrangement of the superior mesenteric artery and splenic *** redundant duodenum must be *** availability of a good venous cuff facilitates the portal vein anastomosis and the positioning of the graft,two key points to prevent *** section line of the arteries must be clean,without atherosclerosis,to prevent arterial *** superior and splenic mesenteric arteries are generally separated by dense fibrolymphatic *** artery can be reconstructed by interposing a"Y"graft from the donor iliac artery;or with an end-to-end anastomosis between the splenic artery and the superior mesenteric *** exquisite technique of bench work helps to prevent the most feared complications of pancreas transplantation:Thrombosis and graft pancreatitis.

关键词： Pancreas transplantation Back-bench work Pancreas thrombosis Graft pancreatitis Arterial reconstruction Pancreas allograft

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Hybrid Security Assessment Methodology for Web Applications

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Computer Modeling in Engineering & Sciences 2021年第1期126卷 89-124页

作者： Roddy A.Correa Juan Ramon Bermejo Higuera javier Bermejo Higuera Juan Antonio SiciliaMontalvo Manuel sanchez Rubio A.Alberto Magrenan Universidad Tecnica Particular de Loja San Cayetano AltoLojaEcuador Escuela Superior de Ingenieria y Tecnologia Universidad Internacional de La RiojaLogrono26006Spain Universidad de la Rioja Logrono26006Spain

This study presents a methodology to evaluate and prevent security vulnerabilities issues for web *** analysis process is based on the use of techniques and tools that allow to perform security assessments of white box and black box,to carry out the security validation of a web application in an agile and precise *** objective of the methodology is to take advantage of the synergies of semi-automatic static and dynamic security analysis tools and manual *** one of the phases contemplated in the methodology is supported by security analysis tools of different degrees of coverage,so that the results generated in one phase are used as feed for the following phases in order to get an optimized global security analysis *** methodology can be used as part of other more general methodologies that do not cover how to use static and dynamic analysis tools in the implementation and testing phases of a Secure Software Development Life Cycle(SSDLC).A practical application of the methodology to analyze the security of a real web application demonstrates its effectiveness by obtaining a better optimized vulnerability detection result against the true and false positive *** analysis with manual checking is used to audit the results,24.6 per cent of security vulnerabilities reported by the static analysis has been checked and it allows to study which vulnerabilities can be directly exploited *** phase is very important because it permits that each reported vulnerability can be checked by a dynamic second tool to confirm whether a vulnerability is true or false positive and it allows to study which vulnerabilities can be directly exploited *** analysis finds six(6)additional critical *** control analysis finds other five(5)important vulnerabilities such as Insufficient Protected Passwords or Weak Password Policy and Excessive Authentication Attacks,two vulnerabilities that permit brute force at

关键词： Web applications security vulnerability weakness security analysis white box black box interactive application security testing static application security testing dynamic application security testing

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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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Gastrointestinal stromal tumors:a multidisciplinary challenge

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World Journal of Gastroenterology 2018年第18期24卷 1925-1941页

作者： Juan Manuel sanchez-Hidalgo Manuel Duran-Martinez Rafael Molero-Payan Sebastian Rufian-Pena Alvaro Arjona-sanchez Angela Casado-Adam Antonio Cosano-Alvarez javier Briceno-Delgado Department of General and Digestive Surgery Reina Sofia University HospitalAvda.Menéndez Pidal s/nCordoba 14004Spain Department of Intern Medicine Reina Sofia University HospitalAvda.Menéndez Pidal s/nCordoba 14004Spain Lipids and Atherosclerosis Research Unit IMIBIC/Hospital Universitario Reina Sofía/Universidad de CórdobaCordoba 14004Spain

Gastrointestinal stromal tumors(GISTs) are the most common mesenchymal tumors located in the alimentary tract. Its usual manifestation is gastrointestinal bleeding. However, small asymptomatic lesions are frequently detected as incidental finding. Characteristically, most GISTs(> 95%) are positive for the KIT protein(CD117) by IHC staining and approximately 80%-90% of GISTs carry a mutation in the c-KIT or PDGFRA genes. Mutational analysis should be performed when planning adjuvant and neoadjuvant therapy, due to its possible resistance to conventional treatment. The arise of tyrosine kinase inhibitor has supposed a revolution in GISTs treatment being useful as adjuvant, neoadjuvant or recurrence disease treatment. That is why a multidisciplinary approach to this disease is required. The correct characterization of the tumor at diagnosis(the diagnosis of recurrences and the evaluation of the response to treatment with tyrosine kinase inhibitors) is fundamental for facing these tumors and requires specialized Endoscopist, Radiologists and Nuclear Medicine Physician. Surgery is the only potentially curative treatment for suspected resectable GIST. In the case of high risk GISTs, surgery plus adjuvantImatinib-Mesylate for 3 years is the standard treatment. Neoadjuvant imatinib-mesylate should be considered to shrink the tumor in case of locally advanced primary or recurrence disease, unresectable or potentially resectable metastasic tumors, and potentially resectable disease in complex anatomic locations to decrease the related morbidity. In the case of Metastatic GIST under Neoadjuvant treatment, when there are complete response, stable disease or limited disease progression, complete cytoreductive surgery could be a therapeutic option if feasible.

关键词： Gastrointestinal stromal tumors Surgery Oncology Radiology Endoscopy Nuclear medicine Pathology Disease management Tyrosine kinase inhibitors Gastroenterology

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Long-term data from a small mammal community reveal loss of diversity and potential effects of local climate change

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Current Zoology 2017年第5期63卷 515-523页

作者： Simone SANTORO Cristina sanchez-SUAREZ Carlos Rouco L. javier PALOMO M. Carmen FERNANDEZ Maura B. KUFNER Sacramento MORENO Ethology and Biodiversity Conservation Department DoSana Biological Station-CSIC Americo Vespucio s/n Seville 41092 Spain Departamento de Zoologfa Campus de Rabanales Universidad de Cordoba Cordoba 14071 Spain Wildlife Ecology and Management Team Private Bag 1930 Dunedin 9054 New Zealand Departamento de Biologia Animal Universidad de Malaga Malaga 29071 Spain Diego de 0norato 67 Barrio Uritorco Cordoba 5003 Argentina

Climate change affects distribution and persistence of species. However, forecasting species＇ re-sponses to these changes requires long-term data series that are often lacking in ecological *** used 15 years of small mammal trapping data collected between 1978 and 2015 in 3 areas atDoSana National Park （southwest Spain） to （i） describe changes in species composition and （ii） test theassociation between local climate conditions and size of small mammal populations. Overall, 5 specieswere captured： wood mouse Apodemus sylvaticus, algerian mouse Mus spretus, greater white-toothed shrew Crocidura russula, garden dormouse Eliomys quercinus, and black rat Rattus rattus. Thetemporal pattern in the proportion of captures of each species suggests that the small mammal diver-sity declined with time. Although the larger species （e.g., E. quercinus）, better adapted to colder cli-mate, have disappeared from our trapping records, M. spretus, a small species inhabiting southwestEurope and the Mediterranean coast of Africa, currently is almost the only trapped species. We used 2-level hierarchical models to separate changes in abundance from changes in probability of captureusing records of A. sylvaticus in all 3 areas and of Mo spretus in 1. We found that heavy rainfall and lowtemperatures were positively related to abundance of A. sylvaticus, and that the number of extremelyhot days was negatively related to abundance of M. spretus. Despite other mechanisms are likely to beinvolved, our findings support the importance of climate for the distribution and persistence of thesespecies and raise conservation concerns about potential cascading effects in the Donana ecosystem.

关键词： climate change, count data, N-mixture models, rodents, spain.

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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 ***,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 *** present manuscript focuses on new aspects of the detection,follow-up,and management of dysplasia according to the latest studies and *** 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 ***,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 ***,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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