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Impact of device resistances in the performance of graphene-based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期 89-99页

作者： óscar Castelló sofía m.lópez baptista Kenji Watanabe Takashi Taniguchi Enrique Diez Jesús Enrique Velázquez-Pérez Yahya m.meziani José m.Caridad Juan A.Delgado-Notario Department of Applied Physics University of Salamanca Unidad de Excelencia en luz y materia Estructurada(lUmES) University of Salamanca Research Center for Electronic and Optical materials National Institute for Materials Science Research Center for materials Nanoarchitectonics National Institute for Materials Science Nanotechnology Group USAL–Nanolab University of Salamanca

In recent years, graphene field-effect-transistors(GFETs) have demonstrated an outstanding potential for terahertz(THz) photodetection due to their fast response and high-sensitivity. Such features are essential to enable emerging THz applications, including 6G wireless communications, quantum information, bioimaging and security. However, the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device, so-called access or parasitic resistances. In this work, we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET detectors. Such dual-gate architectures allow us to fine tune(decrease) the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector, respectively. Our results can be well understood by a series resistance model, as shown by the excellent agreement found between the experimental data and theoretical calculations. These findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

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Standardizing mI-TlIF, a Proposal for a Reproducible Technique

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Open Journal of modern Neurosurgery 2024年第2期14卷 91-103页

作者： Iván Ulises Sámano lópez Jesús Alberto Pérez Contreras Emmanuel Cantú Chávez Diana Chávez lizárraga Ana sofía Peña Blesa Thania Karina Gutiérrez Anchondo Á ngeles Pedregal Ciudad de México México

Background: minim.lly invasive transforaminal lumbar interbody fusion (mI TlIF) is a widely known and performed technique, however its versatility among different physicians continues to hinder its replication and results. Therefore, this study aimed to provide a step-by-step surgical guide to perform a safe mI-TlIF, based on the results obtained in patients operated on by a single surgeon over a period of 12 years. Patients and methods: A retrospective, single center, longitudinal, and observational cohort study was conducted with 931 patients who underwent mI TlIF by a single surgeon between 2010 and 2022 using the technique described on this paper, each with a minimum follow-up of 12 months. Criteria included Schizas classification, listhesis according to meyerding classification, number of levels treated, cage size, and com.lications (screw repositioning or cerebrospinal fluid leak). Patient clinical outcomes were assessed using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) for pre- and postoperative radicular pain. Thin slice CT scans were used to assess the progression of the fusion using the Bridwell classification. In the statistical analysis, percentages, median, and interquartile range (IQR) were calculated. Results: Nine hundred and thirty one patients underwent mI TlIF using the technique described, eight hundred and eighty (94.5%) had a single level treated and fifty one (5.5%) had a 2 level procedure (982 levels), an 8mm cage was placed on five hundred and seventeenlevels (52.7%), six hundred and sixty three levels(67.6%) achieved grade I fusion, two hundred and sixty six levels (27.1%) achieved grade II fusion, 52 levels (5.3) achieved grade III fusion and one level (0.1) achieved a grade IV fusion or non-union. Revision surgery was performed on 3 patients (0.3%) for screw repositioning, cerebrospinal fluid leak was present on 2 patients during surgery and treated before closure. VAS scores and ODI were improved at 12 months postop (V

关键词： mITlIF lumbar Interbody Fusion Technique Pain Relief and Disability

Academic Stress Assessment Using Virtual Reality as an Educational Tool in Spine Surgery

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Open Journal of modern Neurosurgery 2024年第2期14卷 114-123页

作者： Diana Chávez lizárraga Jesús Alberto Pérez Contreras Fernando Alvarado Gómez Evelyn Quintero medina Emmanuel Cantú Chávez Iván Ulises Sámano lópez Ana sofía Peña Blesa Department of Neurosurgery ángeles Pedregal Ciudad de México México Department of Traumatology and Orthopedics Hospital Santa Fe Bogotá Colombia

Introduction: The evaluation of academic stress in medical students and residents is a topic of significant interest, given the considerable challenges they face during their learning process with traditional teaching methods. The use of technologies like virtual reality presents an opportunity to enhance their skills through sim.lations and training. The main objective of this study is to qualitatively assess the stress levels experienced by medical students and residents by integrating virtual reality into their current learning methods, aiming to improve their ability to manage stressors in their practice. material and methods: A questionnaire was conducted with 12 medical students and 12 Traumatology and orthopedics residents. The purpose of the questionnaire was to evaluate the levels of academic stress using the SISCO inventory. The stress levels were calculated by transforming average values into percentages, and the following criteria were assigned: 0 to 33% for m.ld Stress, 34 to 66% for moderate Stress, and 67 to 100% for Deep Stress. Then, a virtual reality class focused on spine surgery was provided. Both medical students and residents were trained using the Non Nocere SharpSurgeon software platform and Oculus Quest 2 virtual reality glasses. At the end of the session, a second questionnaire related to the practice with virtual reality was conducted with the same evaluation criteria and a comparative analysis was carried out. Results: 12 undergraduate students from Hospital Angeles mexico, CDmX and 12 traumatology and orthopedics residents at Hospital Santa Fe, Bogota were evaluated. The students in CDmX reported an average qualitative stress of 28.50% during habitual practices, which decreased to an average of 14.67% after virtual reality practice. Residents in Bogotá experienced an average qualitative stress of 30.50% with their current learning methods but this reduced to an average of 13.92% after using virtual reality. These findings indicate that t

关键词： Virtual Reality Academic Stress learning Strategies Spine Surgery Training

Hydrogeochemical Studies in Drought Scenarios: Canelones, Uruguay Case Study

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Journal of Geoscience and Environment Protection 2024年第5期12卷 188-217页

作者： Karina Pamoukaghlian Elena Alvareda mariano Cáceres Rebeca Panzl marcelo Aboy sofìa Da Rocha Pablo Gamazo maría Paula Collazo Instituto de Ciencias Geoló gicas Facultad de Ciencias Universidad de la Rep&#250blica Montevideo Uruguay Departamento del Agua Centro Universitario Regional Litoral Norte Universidad de la Rep&#250blica Salto Uruguay Á rea Toxicolog&#237a Departamento Estrella Campos Facultad de Qu&#237mica Universidad de la Rep&#250blica Montevideo Uruguay

The water scarcity in quality and quantity is becoming more noticeable and an urgent concern around the world. In Uruguay, these issues become exacerbated by the need to obtain drinking water in coastal areas, influenced by the climate change. Basic and structural geologies are strong conditioners in heterogeneous coastal aquifers. The objective of this study is to characterize the hydrochemistry of the fractured aquifers after having identified the main bearing fractures and the causes of aleatoreous water scarcity and quality problems, for hydric resources sustainable management. Identification of water bearing fracture, hydrogeochemical analysis and water quality evaluation are specific objectives. Some strategies were performed: 1) a base map in QGIS software;2) fracture photointerpretation;3) geological correlation;4) statistical analysis of the background geochemistry data;5) ions analysis of strategically located wells. There were found water bearing fractures corresponding to 28 m3/h maximum flow rate for the NW-SE and 12 m3/h maximum flow rate for the NE-SW fracture direction, respectively. Besides, there could be a problem related to the high Sodium (Na) and Chloride (Cl) levels. In this respect, having previous data from 25 well sam.les, ions geochemical analysis has been carried out for 14 wells from Costa Azul and surrounding to have a first approach about the possible cause for the high values of Na (max. 385 mg/l) and Cl (max. 381 mg/l). The selected area for this study has a particular characteristic, because it corresponds to a heterogeneous fractured aquifer, which makes it difficult to catch water with enough flow rates and water quality to meet the population demand.

关键词： Water Bearing Fractures Hydrogeochemistry Water Quality Sustainable management

Infrastructure for collaborative science and societal applications in the Columbia River estuary

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Frontiers of Earth Science 2015年第4期9卷 659-682页

作者： Antonio m. baptista NSF Science and Technology Center for Coastal margin Observation & Prediction Oregon Health & Science University Portland Oregon 97239 USA Oregon Health & Science University Astoria Oregon 97103 USA Portland State University Portland Oregon 97201 USA Applied Physics laboratory of the University of Washington Seattle Washington 98105 USA Oregon State University Corvallis Oregon 97331 USA Formerly University of maryland Center for Environmental Studies Maryland 21613 USA

To meet societal needs, modem estuarine science needs to be interdisciplinary and collaborative, combine discovery with hypotheses testing, and be responsive to issues facing both regional and global stakeholders. Such an approach is best conducted with the benefit of data-rich environments, where information from sensors and models is openly accessible within convenient timeframes. Here, we introduce the operational infrastruc- ture of one such data-rich environment, a collaboratory created to support （a） interdisciplinary research in the Columbia River estuary by the m.lti-institutional team of investigators of the Science and Technology Center for Coastal margin Observation ＆ Prediction and （b） the integration of scientific knowledge into regional decision making. Core components of the operational infrastructure are an observation network, a modeling system and a cyber-infrastructure, each of which is described. The observation network is anchored on an extensive array of long-term stations, many of them interdisciplinary, and is com.lemented by on-demand deployment of temporary stations and mobile platforms, often in coordinated field campaigns. The modeling system is based on finite- element unstructured-grid codes and includes operational and process-oriented sim.lations of circulation, sediments and ecosystem processes. The flow of information is managed through a dedicated cyber-infrastructure, con- versant with regional and national observing systems.

关键词： estuaries observations numerical modeling,cyber-infrastructure Columbia River

Effect of Fe_(3)O_(4) nanoparticles on magnetic xerogel composites for enhanced removal of fluoride and arsenic from aqueous solution

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Water Science and Engineering 2022年第4期15卷 305-317页

作者： Sasirot Khamkure Victoria Bustos-Terrones Nancy Jakelin Benitez-Avila maría Fernanda Cabello-lugo Prócoro Gamero-m.lo sofía Esperanza Garrido-Hoyos Juan marcos Esparza-Schulz Postgraduate Department National Council for Science and Technology(CONACyT)-Mexican Institute of Water TechnologyMorelos 62574Mexico Department of Environmental Technology Engineering Polytechnic University of the State of MorelosMorelos 62550Mexico Department of Sustainability of Natural Resources and Energy Center for Research and Advanced Studies of the National Polytechnic InstituteCoahuila 25900Mexico Department of Chemistry Metropolitan Autonomous University Campus IztapalapaMexico City 09340Mexico

Fe_(3)O_(4)magnetic xerogel composites were prepared by polycondensation of resorcinol(R)-form.ldehyde reaction via a sol-gel process in an aqueous solution through varying the m.lar ratio of Fe_(3)O_(4)nanoparticles(mNPs),catalyst(C),and water(W)*** were obtained by co-precipitation(mC),oxidation of iron salts(mO),or solvotherm.l synthesis(mS).Both mNPs and magnetic xerogels were examined regarding the performance of arsenic and fluoride removal in a batch *** mC-based mNPs had higher adsorption capacities for both fluoride(202.9 mg/g)and arsenic(3.2 mg/g)than other mNPs in optimum *** X-ray diffraction,Fourier transform infrared spectroscopy,and energy-dispersive X-ray spectroscopy confirmed that Fe was composed into the polymeric matrix of magnetic xerogels that contained 0.59%-4.42%of Fe with a m.lar ratio of mNPs(m)to R between 0.01 and *** low R/C and optimum m/R ratios,an increase in the surface area of magnetic xerogels affected the fluoride and arsenic adsorption *** magnetic xerogel composites with the mC-based mNPs prepared at a fixed R/C ratio(100)and at different R/W(0.05-0.06)and m/R(0.07-0.10)ratios had a high arsenic removal efficiency of 100%at an As(V)concentration of 0.1 mg/l and pH of *** maximum adsorption capacities of magnetic xerogels were approximately five times higher than those of the xerogels without mNP ***,Fe_(3)O_(4)nanoparticles enhanced the adsorption of arsenate and *** variations of alkaline catalyst and water content significantly affected the resulting properties of textural and surface chemistry of magnetic xerogel composites.

关键词： Adsorption Arsenic Fluoride Composite magnetite nanoparticles Xerogel

CD300a inhibits CD16-mediated NK cell effector functions in HIV-1-infected patients

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Cellular & m.lecular Immunology 2019年第12期16卷 940-942页

作者： Joana Vitallé Iñigo Terrén Ane Orrantia Raquel Pérez-Garay Francesc Vidal JoséA.Iribarren Carmen Rodríguez Ana m.lópez lirola Enrique Bernal Olatz Zenarruzabeitia Francisco Borrego Immunopathology Group Biocruces Bizkaia Health Research InstituteBarakaldoSpain Hospital Universitari de Tarragona Joan XXIII IISPVUniversitat Rovira i VirgiliTarragonaSpain Servicio de Enfermedades Infecciosas Hospital Universitario DonostiaInstituto de Investigación Sanitaria BiodonostiaDonostia-San SebastiánSpain Centro Sanitario Sandoval Hospital Clínico San CarlosInstituto de Investigación Sanitaria San CarlosMadridSpain Hospital Universitario de Canarias Santa Cruz de TenerifeSpain Department of Clinical medicine Universidad de Murcia and Hospital General Universitario Reina SofíaMurciaSpain Ikerbasque Basque Foundation for ScienceBilbaoSpain

Natural killer(NK)cell-mediated antibody-dependent cellular cytotoxicity(ADCC)through CD16 plays a critical role in antihuman immunodeficiency virus(HIV)responses.1–3 CD300a is a surface receptor highly expressed on NK cells that has the capacity to inhibit NK cell-mediated cytotoxicity in healthy donors.4 The CD300a m.lecule has been related to several viral infections and is able to diminish the NK cell killing of pseudorabies-infected cells through interactions with its ligands phosphatidylserine and phosphatidylethanolamine.5 In addition,CD300a expression on B and CD4+T lymphocytes is altered during HIV-1 infection,and combined antiretroviral therapy(cART)does not restore nonpathological expression levels.5,6 However,the expression and function of CD300a on NK cells during HIV-1 infection is still *** have determined the surface expression of CD300a on different NK cell subsets and the capacity of this receptor to inhibit CD16-induced NK cell effector functions in healthy and HIV-1 infected individuals.

关键词： CD16 CD30 ADCC

Information Transmission in Phase Synchronous Chaotic Arrays

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Chinese Physics letters 2006年第3期23卷 560-563页

作者： m. S. baptista C. Zhou J. Kurths Universitat Potsdam Institut for Physik Am Neuen Palais 10 D-14469 Potsdam Deutschland

We show many versatile phase synchronous configurations that emerge in an array of coupled chaotic elements due to the presence of a periodic stim.lus. Then, we explain the relevance of these configurations to the understanding of how information about such a stim.lus is transmitted from one side to the other in this array. The stim.lus actively creates the ways to be transmitted, by making the chaotic elements to phase synchronize.

关键词： NEURAl SPIKE TRAINS SYNCHRONIZATION

Pollution of Airborne Fungi in Naturally Ventilated Repositories of the Provincial Historical Archive of Santiago de Cuba (Cuba)

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Journal of Atmospheric Science Research 2022年第2期5卷 13-32页

作者： sofía Borrego Alian m.lina Yuneisis Bonne Anyilena González lidiersy méndez Conservation Preventive laboratory National Archive of the Republic of CubaHavana cityCuba Conservation Department Provincial Historic Archive of Santiago de CubaSantiago de Cuba cityCuba

Environmental fungi can damage the documentary heritage conserved in archives and affect the personnel’s health if their concentrations,thermo-hygrometric parameters and ventilation conditions are not adequate,problems that can be accentuated by Climate *** aims of this work were to identify and to characterize the airborne fungal pollution of naturally ventilated repositories in the Provincial Historical Archive of Santiago de Cuba and predict the risk that these fungi pose to the staff’s *** air of three repositories of this archive and the outdoor air were sam.led in an occasion every time in 2015,2016 and 2017 using a SAS *** obtained fungal concentrations varied from 135.6 CFU/m^(3) to 421.1 CFU/m^(3) and the indoor/outdoor ratios fluctuated from 0.7 to 4.2,evidencing a variable environmental quality over time,but in the third sam.ling the repositories environments showed good *** and Cladosporium were the predominant genera in these *** was a prevailed species in indoor air,while *** and *** were the species that showed the greatest sim.larities with the outdoor *** and Talaromyces genera as well as the species Aspergillus uvarum,Alternaria ricini and Cladosporium staurophorum were the first findings for environments of Cuban *** species(***,***,***,***)indicators of moisture problems in the repositories were detected;they are also opportunistic pathogens and toxigenic species but their concentrations were higher than the recommended,demonstrating the potential risk to which the archive personnel is exposed in a circumstantial way.

关键词： Archive environments Fungal pollution Indoor air Environmental quality Ventilated repositories Toxigenic species