Sensitivity analysis of surface ozone to modified initial and boundary conditions in both rural and industrial zones

International audienceA three-dimensional air quality model based on a set of chemical species mass conservation equations describes the time evolution of chemical species in the atmosphere. In order to solve this set of equations, proper choices of initial and boundary conditions are needed. Ideally, initial and boundary conditions should be determined on the basis of observations. However, since such high-resolution observations are generally not available, it becomes necessary to use other information sources to specify the initial and boundary values. The fact that both the initial and the boundary conditions are specified with some degree of presumption makes it important to evaluate their influence in the model results. In this paper we present a study of the impact of initial and boundary concentrations on the modelled surface ozone concentration over two environments: Huelva and Badajoz, an industrial and a rural zone, respectively. The impacts are analysed for the same meteorological period (10?15 August 2003)

The impact of biogenic VOC emissions on photochemical ozone formation during a high ozone pollution episode in the Iberian Peninsula in the 2003 summer season

Throughout Europe the summer of 2003 was exceptionally warm, especially July and August. The European Environment Agency (EEA) reported several ozone episodes, mainly in the first half of August. These episodes were exceptionally long-lasting, spatially extensive, and associated to high temperatures. In this paper, the 10$ndash;15 August 2003 ozone pollution event has been analyzed using meteorological and regional air quality modelling. During this period the threshold values of the European Directive 2002/3/EC were exceeded in various areas of the Iberian Peninsula. <br><br> The aim of this paper is to computationally understand and quantify the influence of biogenic volatile organic compound (BVOC) emissions in the formation of tropospheric ozone during this high ozone episode. Being able to differentiate how much ozone comes from biogenic emissions alone and how much comes from the interaction between anthropogenic and biogenic emissions would be helpful to develop a feasible and effective ozone control strategy. The impact on ozone formation was also studied in combination with various anthropogenic emission reduction strategies, i.e., when anthropogenic VOC emissions and/or NO<sub>x</sub> emissions are reduced. The results show a great dependency of the BVOC contribution to ozone formation on the antropoghenic reduction scenario. In rural areas, the impact due to a NO<sub>x</sub> and/or VOC reduction does not change the BVOC impact. Nevertheless, within big cities or industrial zones, a NO<sub>x</sub> reduction results in a decrease of the biogenic impact in ozone levels that can reach 85 μg/m<sup>3</sup>, whereas an Anthropogenic Volatile Organic Compound (AVOC) reduction results in a decrease of the BVOC contribution on ozone formation that varies from 0 to 30 μg/m<sup>3</sup> with respect to the contribution at the same points in the 2003 base scenario. On the other hand, downwind of the big cities, a decrease in NO<sub>x</sub> produces a minor contribution of biogenic emissions and a decrease in AVOCs results in greater contributions of BVOCs to the formation of ozone

Security Policies to Mitigate Attacks VLAN Hopping in the Data Link Layer of LA Networks

A proposal of security policies based on the ISO 27002 standard is presented, which allows to mitigate VLAN HOPPING attacks at the data link layer level in LAN networks, as it is evident that network administrators pay more attention to policies to ensure the layers of the OSI model, so that internal users with certain privileges can take advantage of these vulnerabilities to access valuable information of the organization. For this purpose, a base network infrastructure of the companies in the city of Riobamba-Ecuador was determined as a case study. In this scenario, a standard four-phase Pentesting was performed to test VLAN HOPPING attacks (Switch Spoofing and Double Tagging) before and after applying the proposed policies, resulting in a 100% mitigation of the technological vulnerabilities found and 90% of organizational, operational, and physical vulnerabilities.     Keywords: VLAN HOPPING, Security Policies, Vulnerability Mitigation, Security Mechanism

Monolithic CIGS-Perovskite Tandem Cell for an Optimal Light Harvesting Without Current Matching

We present a novel monolithic architecture for optimal light harvesting in multijunction thin film solar cells. In the configuration we consider, formed by a perovskite (PVK) cell overlying a CIGS cell, the current extracted from the two different junctions is decoupled by the insertion of a dielectric nonperiodic photonic multilayer structure. This photonic multilayer is designed by an inverse integration approach to confine the incident sunlight above the PVK band gap in the PVK absorber layer, while increasing the transparency for sunlight below the PVK band gap for an efficient coupling into the CIGS bottom cell. To match the maximum power point voltages in a parallel connection of the PVK and CIGS cells, the latter is divided into two subcells by means of a standard three-laser scribing connection. Using realistic parameters for all the layers in the multijunction architecture we predict power conversion efficiencies of 28%. This represents an improvement of 24% and 26% over the best CIGS and PVK single-junction cells, respectively, while at the same time outperforms the corresponding current-matched standard tandem configuration by more than two percentage points.Peer ReviewedPostprint (author's final draft

Resolución de la Ecuación Diferencial Parcial Hiperbólica de segundo orden con término fuente mediante el Método de D’Alembert-Green

In the present work, we study a non-homogeneous second-order partial hyperbolic differential equation, its canonical form, its resolution using D’Alembert’s formula and Green’s theorem. Only mixed initial conditions that are not homogeneous are required to solve this problem. There are several physical problems that lead to this type of mathematical model, so this technique of resolution contributes to the knowledge of finding explicit solutions of problems such as two-dimensional wave type. Within the results the explicit solution of three cases is generated:regarding the homogeneity and non-homogeneity of the initial conditions and the term source, from the point of view of analytical solution for continuous functions.En el presente trabajo se estudia una Ecuación Diferencial Parcial Hiperbólica con término fuente no homogéneo de segundo orden, su forma canónica, su resolución mediante la fórmula de D’Alembert y el Teorema de Green.Para la resolución de este problema solo se requiere las condiciones iniciales mixtas. Existen diversos problemas físicos que conducen a este tipo de modelo matemático, por lo cual esta técnica de resolución contribuye al conocimiento de encontrar soluciones explícitas de problemas como por ejemplo tipo onda bidimensional sometidos a fuerzas exteriores. Dentro de los resultados se genera la solución explícita de tres casos: respecto a la homogeneidad y no homogeneidad de las condiciones iniciales y del término fuente, desde el punto de vista de solución analítica para funciones de clase C2

GENDER DIFFERENCES in METABOLIC PROFILE and CARDIOVASCULAR RISK AMONG BRAZILIAN HIV-INFECTED PATIENTS ON HAART: RAPID II STUDY

Universidade Federal de São Paulo, São Paulo, BrazilInst Infectol Emilio Ribas, São Paulo, BrazilHosp & Maternidade Celso Pierro, Campinas, SP, BrazilUniv Fed Bahia, Salvador, BA, BrazilBristol Myers Squibb Co, São Paulo, BrazilBristol Myers Squibb Co, Plainsboro, NJ USAHosp Correia Picanco, Recife, PE, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc

Immunostimulatory efficacy and protective potential of putative TgERK7 protein in mice experimentally infected by Toxoplasma gondii

© 2020 The Author(s) The extracellular signal-regulated kinases (ERKs) serve as important determinants of cellular signal transduction pathways, and hence may play important roles during infections. Previous work suggested that putative ERK7 of Toxoplasma gondii is required for efficient intracellular replication of the parasite. However, the antigenic and immunostimulatory properties of TgERK7 protein remain unknown. The objective of this study was to produce a recombinant TgERK7 protein in vitro and to evaluate its effect on the induction of humoral and T cell-mediated immune responses against T. gondii infection in BALB/c mice. Immunization using TgERK7 mixed with Freund's adjuvants significantly increased the ratio of CD3e+CD4+ T/CD3e+CD8a+ T lymphocytes in spleen and elevated serum cytokines (IFN-γ, IL-2, IL-4, IL-10, IL-12p70, IL-23, MCP-1, and TNF-α) in immunized mice compared to control mice. On the contrary, immunization did not induce high levels of serum IgG antibodies. Five predicted peptides of TgERK7 were synthesized and conjugated with KLH and used to analyze the antibody specificity in the sera of immunized mice. We detected a progressive increase in the antibody level only against TgERK7 peptide A (DEVDKHVLRKYD). Antibody raised against this peptide significantly decreased intracellular proliferation of T. gondii in vitro, suggesting that peptide A can potentially induce a protective antibody response. We also showed that immunization improved the survival rate of mice challenged with a virulent strain and significantly reduced the parasite cyst burden within the brains of chronically infected mice. Our data show that TgERK7-based immunization induced TgERK7 peptide A-specific immune responses that can impart protective immunity against T. gondii infection. The therapeutic potential of targeting ERK7 signaling pathway for future toxoplasmosis treatment is warranted

Patterns of media coverage repeated in online abuse on high-profile criminal cases

What relationship do the mainstream media have with online abuse on high-profile criminal cases? This article hopes to make a start at answering this question by examining tweets containing the #McCann hashtag, utilised by a highly engaged community of users to comment on all matters related to the disappearance of British child Madeleine McCann. On #McCann, the child’s parents and other players are often singled out as the perpetrators of her disappearance and other crimes, in a blend of harassment, defamation and insults with conspiracy theories, disinformation and a strong anti-establishment vein typical of the posttruth era. Through an experimental digital ethnography blending elements of content and discourse analysis, this research has observed the #McCann conversation and analysed 500 tweets with the hashtag, observing that some of the most offensive theories posted by users on Twitter reprised themes seen in the mainstream media at the time of the disappearance, which resulted in defamation lawsuits by the McCanns and in complaints about unethical reporting at the Leveson Inquiry. This raises questions about the mainstream media’s responsibility and duty of care towards people they report on in the digital age, and showcases a symbiotic yet diffident relationship between anti-establishment online users and traditional news media

Automatización del proceso de limpieza del filtro tipo canastilla y malla del sistema buque tanques de la terminal marítima Pozos Colorados

The paper presents a technological solution to improve a process in the maritime oil terminal, Pozos Colorados. The objective of the solution is the filter cleaning automation of discharge system an oil tanker ship. The purpose of the solution is to improve the conditions of industrial safety and occupational health of workers who perform this function manually, and optimize the process of receiving hydrocarbons by improving operating times. The methodology is basic and detailed engineering, applied to automation engineering, this contemplating the narrative: process, design and evaluation is used to prepare the proposal. The proposal delivers the design of: the hydraulic system, the electrical system and the control system. The solution includes: capturing water from the storage pool and by means of a controlled pressure electric pump, transporting the fluid to the filtering area; and the filters are cleaned using a sprinkler branch located inside the basket. The washing process is manipulated by means of solenoid valves and a variable speed drive, these are governed by a programmable logic controller, this PLC receives information on the variables involved by means of sensors. The modeling, simulation and evaluations of the proposal support the possibility of implementing automation by making some adjustments to the existing infrastructure and adding electrical, mechanical and electronic elementsEl artículo presenta una solución tecnológica para mejorar un proceso en la terminal marítima petrolera Pozos Colorados. El objetivo de la solución es automatizar el lavado de los filtros tipo canastilla y malla del sistema de filtrado Buquetanque empleado en el recibo de hidrocarburos. El propósito de la solución es mejorar las condiciones de seguridad industrial y salud ocupacional de los trabajadores que realizan esta función de forma manual, y optimizar el proceso de recepción de hidrocarburos al mejorar los tiempos de operación. Para la elaborar la propuesta se emplea la metodología fundamenta en la ingeniería básica y de detalle, aplicada a la ingeniería de automatización, contemplando la narrativa: de proceso, de diseño y de evaluación. La propuesta entrega el diseño de: el sistema hidráulico, el sistema eléctrico y el sistema de control. La solución contempla: captar el agua de la piscina de almacenamiento, y por medio de una electrobomba de presión controlada transportar el fluido hasta la zona del filtrado; y posteriormente limpiar los filtros utilizando un ramal de aspersores ubicados dentro la canasta. El proceso de lavado es manipulado por medio de electroválvulas y un variador de velocidad, estos están gobernadas por un controlador lógico programable, este recibe información de las variables involucradas por medio de sensores. El modelado, simulación y evaluaciones de la propuesta sustentan la posibilidad de implementar la automatización realizando algunas adecuaciones a la infraestructura existente y adicionando unos elementos eléctricos, mecánicos y electrónico