Electron Emission of Pt: Experimental Study and Comparison With Models in the Multipactor Energy Range

"(c) 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works."Experimental data of secondary emission yield (SEY) and electron emission spectra of Pt under electron irradiation for normal incidence and primary energies lower than 1 keV are presented. Several relevant magnitudes, as total SEY, elastic backscattering probability, secondary emission spectrum, and backscattering coefficient, are given for different primary energies. These magnitudes are compared with theoretical or semiempiricalThis work was supported in part by the Ministerio de Economia y Competitividad under Project TEC2013-47037-C5-4-R, and in part by MICIIN through the Space Programme under Project AYA2012-39832-C02-01/02. The review of this paper was arranged by Editor M. Thumm.Bronchalo, E.; Coves, A.; Mata Sanz, R.; Gimeno Martinez, B.; Montero, I.; Galán, L.; Boria Esbert, VE.... (2016). Electron Emission of Pt: Experimental Study and Comparison With Models in the Multipactor Energy Range. IEEE Transactions on Electron Devices. 63(8):3270-3277. https://doi.org/10.1109/TED.2016.2580199S3270327763

Cellular vaccines in listeriosis: role of the Listeria antigen GAPDH

The use of live Listeria-based vaccines carries serious difficulties when administrated to immunocompromised individuals. However, cellular carriers have the advantage of inducing multivalent innate immunity as well as cell-mediated immune responses, constituting novel and secure vaccine strategies in listeriosis. Here, we compare the protective efficacy of dendritic cells (DCs) and macrophages and their safety. We examined the immune response of these vaccine vectors using two Listeria antigens, listeriolysin O (LLO) and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH), and several epitopes such as the LLO peptides, LLO189-201 and LLO91-99 and the GAPDH peptide, GAPDH1-22. We discarded macrophages as safe vaccine vectors because they show anti-Listeria protection but also high cytotoxicity. DCs loaded with GAPDH1-22 peptide conferred higher protection and security against listeriosis than the widely explored LLO91-99 peptide. Anti-Listeria protection was related to the changes in DC maturation caused by these epitopes, with high production of interleukin-12 as well as significant levels of other Th1 cytokines such as monocyte chemotactic protein-1, tumor necrosis factor-α, and interferon-γ, and with the induction of GAPDH1-22-specific CD4(+) and CD8(+) immune responses. This is believed to be the first study to explore the use of a novel GAPDH antigen as a potential DC-based vaccine candidate for listeriosis, whose efficiency appears to highlight the relevance of vaccine designs containing multiple CD4(+) and CD8(+) epitopes

Biomarker tools to Design Clinical Vaccines Determined from a study of annual Listeriosis Incidence in Northern spain

Two regions of northern Spain, Gipuzkoa, and Cantabria present high annual incidence of listeriosis (1.86 and 1.71 cases per 100,000 inhabitants, respectively). We report that the high annual incidences are a consequence of infection with highly virulent Listeria monocytogenes isolates linked to fatal outcomes in elderly patients with cancer. In addition, listeriosis patients with cancer present low IL-17A/IL-6 ratios and significantly reduced levels of anti-GAPDH1?22 antibodies, identified as two novel biomarkers of poor prognosis. Analysis of these biomarkers may aid in reducing the incidence of listeriosis. Moreover, GAPDH1?22-activated monocyte-derived dendritic cells of listeriosis patients with cancer seem useful tools to prepare clinical vaccines as they produce mainly Th1 cytokines

A Novel Therapy for Melanoma Developed in Mice: Transformation of Melanoma into Dendritic Cells with Listeria monocytogenes

Listeria monocytogenes is a gram-positive bacteria and human pathogen widely used in cancer immunotherapy because of its capacity to induce a specific cytotoxic T cell response in tumours. This bacterial pathogen strongly induces innate and specific immunity with the potential to overcome tumour induced tolerance and weak immunogenicity. Here, we propose a Listeria based vaccination for melanoma based in its tropism for these tumour cells and its ability to transform in vitro and in vivo melanoma cells into matured and activated dendritic cells with competent microbicidal and antigen processing abilities. This Listeria based vaccination using low doses of the pathogen caused melanoma regression by apoptosis as well as bacterial clearance. Vaccination efficacy is LLO dependent and implies the reduction of LLO-specific CD4+ T cell responses, strong stimulation of innate pro-inflammatory immune cells and a prevalence of LLO-specific CD8+ T cells involved in tumour regression and Listeria elimination. These results support the use of low doses of pathogenic Listeria as safe melanoma therapeutic vaccines that do not require antibiotics for bacterial removal

Listeria effective vaccines against melanoma

La hipótesis principal de este estudio es que Listeria monocytogenes tiene propiedades adyuvantes antitumorales que la convierten en un vector para una vacuna terapéutica efectiva contra el cáncer, en este caso, el melanoma. El objetivo principal de este trabajo ha sido el diseño y desarrollo de una vacuna terapéutica basada en células dendríticas y gliconanopartículas de oro (GNP) con péptidos de la bacteria intracelular Listeria monocytogenes que fuese eficaz de generar regresión del melanoma en nuestro propio modelo de melanoma murino, el melanoma B16F10 en ratones C57BL/6.Máster en Biología Molecular y Biomedicin

Experimental Study of the Multipactor Effect in a Partially Dielectric-Loaded Rectangular Waveguide

This letter presents the experimental study of the multipactor threshold in a partially dielectric-loaded rectangular waveguide, whose results validate a multipactor model recently developed by the authors, which includes the charge distribution appearing on the dielectric surface during the multipactor discharge. First, the variation of the multipactor RF voltage threshold has been theoretically analyzed in different waveguide configurations: in an empty waveguide, and also in the cases of a one-sided and two-sided dielectric-loaded waveguides. To reach this aim, an in-house Monte Carlo simulation tool has been developed. The Secondary Electron Yield (SEY) of the metallic and dielectric materials used in the numerical simulations have been measured experimentally. Finally, an aluminum WR-75 symmetric E-plane rectangular waveguide transformer has been designed and fabricated, in which several multipaction tests have been carried out to validate the in-house software tool, demonstrating an excellent agreement between the simulation results and the experimental data.This work was supported by the Agencia Estatal de Investigaci´on (AEI) and by the Uni´on Europea through the Fondo Europeo de Desarrollo Regional - FEDER - “Una manera de hacer Europa” (AEI/FEDER, UE), under the Research Projects TEC2016-75934-C4-2-R and TEC2016-75934-C4-1-R

Estudio de selectividad frente a disoluciones multicomponente de sensores de glucosa mediante tecnología planar de microondas

Resumen Durante los últimos años, el desarrollo de sensores de concentración de glucosa a través de resonadores planares de microondas ha llamado la atención de una considerable parte de la comunidad científica. Tras mostrar algunos resultados prometedores, los sensores experimentales actuales se enfrentan a ciertos desafíos primordiales. Entre ellos, el más crítico parece ser la selectividad a la concentración de glucosa frente a las variaciones de las concentraciones de otros componentes o parámetros. En este artículo estudiamos la selectividad experimental de sensores basados en resonadores de microondas al medir disoluciones multicomponente. Evaluamos minuciosamente el funcionamiento de estos sensores al medir disoluciones de agua pura, NaCl, albúmina y glucosa, analizando el impacto de las variaciones simultáneas de las concentraciones de glucosa y albúmina. Los resultados muestran una clara influencia de la concentración de albúmina en las medidas de la concentración de glucosa, lo que apunta a una falta de selectividad para estos los sensores. Hemos modelado esta influencia, y a partir de ella proponemos estrategias para afrontar el desafío de la selectividad con este tipo de sensores

On the Selectivity of Planar Microwave Glucose Sensors with Multicomponent Solutions

The development of glucose concentration sensors by means of microwave planar resonant technology is an active field attracting considerable attention from the scientific community. Although showing promising results, the current experimental sensors are facing some fundamental challenges. Among them, the most critical one seems to be the selectivity of glucose concentration against the variations of the concentrations of other components or parameters. In this article, we investigate the selectivity of microwave planar resonant sensors when measuring multicomponent solutions. Three sensors are involved, two of them having been designed looking for a more simplified system with a reduced size, and the third one has been specially developed to improve the sensitivity. The performance of these sensors is thoroughly assessed with a large set of measurements involving multicomponent solutions composed of pure water, NaCl, albumin at different concentrations and glucose at different concentrations. The impact of the simultaneous variations of the concentrations of glucose and albumin on the final measurements is analyzed, and the effective selectivity of the sensors is discussed. The results show a clear influence of the albumin concentration on the measurements of the glucose concentration, thereby pointing to a lack of selectivity for all sensors. This influence has been modeled, and strategies to manage this selectivity challenge are inferred

Study of the selectivity of planar microwave glucose sensors against multicomponent solutions

[Resumen] Durante los últimos años, el desarrollo de sensores de concentración de glucosa a través de resonadores planares de microondas ha llamado la atención de una considerable parte de la comunidad científica. Tras mostrar algunos resultados prometedores, los sensores experimentales actuales se enfrentan a ciertos desafíos primordiales. Entre ellos, el más crítico parece ser la selectividad a la concentración de glucosa frente a las variaciones de las concentraciones de otros componentes o parámetros. En este artículo estudiamos la selectividad experimental de sensores basados en resonadores de microondas al medir disoluciones multicomponente. Evaluamos minuciosamente el funcionamiento de estos sensores al medir disoluciones de agua pura, NaCl, albúmina y glucosa, analizando el impacto de las variaciones simultáneas de las concentraciones de glucosa y albúmina. Los resultados muestran una clara influencia de la concentración de albúmina en las medidas de la concentración de glucosa, lo que apunta a una falta de selectividad para estos los sensores. Hemos modelado esta influencia, y a partir de ella proponemos estrategias para afrontar el desafío de la selectividad con este tipo de sensores.[Abstract] During the last years, the development of glucose concentration sensors with microwave planar resonators has raised the attention of a notable part of the academic community. After showing some promising results, the current experimental sensors are facing certain key challenges. Particularly, the selectivity to the glucose concentration against the changes in the concentrations of other solutes or variables is one of the most worrying ones. In this paper we perform a close scrutiny of the experimental selectivity found in microwave resonant sensors when making measurements with multicomponent solutions. We painstakingly evaluate the performance of these sensors while measuring solutions of pure water, NaCl, albumin and glucose, and we analyze the influence of the simultaneous variations of the glucose and albumin concentrations. The results reveal an evident influence of the albumin concentration on the identification of the glucose concentration, therefore indicating a weak selectivity. We have modelled this effect, and we thereby propose strategies for dealing with this selectivity issue.Ministerio de Ciencia e Innovación; PID2019-111023RB-C32Generalitat Valenciana; CIAPOS/2021/26