Simulación numérica del sistema circulatorio

Proyecto de Graduación (Licenciatura en Ingeniería en Electrónica) Instituto Tecnológico de Costa Rica. Escuela de Ingeniería Electrónica, 2011.Este documento presenta el estudio realizado para la implementación de una simulación del sistema circulatorio. El estudio se enfoca en el modelado matemático basado en parámetros concentrados. Durante el desarrollo del proyecto se revisaron varios modelos matemáticos existentes y se implementaron seis de ellos en la versión MATLAB/Simulink R2011a. Para construir estos modelos se utilizó la biblioteca “Cardiovascular Simulation Toolbox”. Esta biblioteca fue desarrollada en MATLAB/Simulink R14 por O. Barnea y sus colaboradores en la Universidad de Tel Aviv [1]. La biblioteca original presentaba problemas de compatibilidad con las versiones más recientes del programa, por lo que primero fue necesario reescribir la biblioteca para hacerla compatible, y luego desarrollar los modelos requeridos. Se escogió un modelo del sistema cardiovascular completo con el propósito de simular el comportamiento del sistema circulatorio en condiciones normales de salud, y en este proyecto se ajustaron los parámetros del sistema cardiovascular para poder simular la insuficiencia cardíaca sistólica, que no era parte del modelo inicial. Además se presenta un modelo sencillo para simular el comportamiento teórico de un dispositivo de asistencia ventricular. Con este modelo se implementó una simulación del corazón acoplado al VAD y se comprobó que el aparato ejerce succión en el ventrículo izquierdo. __________________________________________________________________________ Abstract This report contains an academic research to implement a simulation of the cardiovascular system. The study is based on mathematical modeling using lumped parameters. On this project, some existent mathematical models were reviewed, and six of them were implemented on MATLAB/Simulink R2011a. The models are based on the “Cardiovascular Simulation Toolbox” library. This library was developed by O. Barnea and his collaborators at the Tel-Aviv University, using MATLAB/Simulink R14 [1]. The original library presented compatibility problems with the current version of the software, so in this project the library was updated to be compatible with the newer versions of MATLAB, and then it is used for the implementation of some models. We selected one mathematical model of the complete cardiovascular system able to produce simulations of the healthy circulatory system with normal hemodynamics. The input parameters of this model were adjusted to obtain another simulation, aimed to generate the hemodynamic parameters of a person with systolic heart failure. Also a theoretical model of a ventricular assist device is presented, able to produce a constant blood flow. With this model we implemented a simulation of the effects of the VAD in the circulatory system, and observed the suction produced by the VAD on the left ventricle

Simulación numérica del sistema circulatorio

Proyecto de Graduación (Licenciatura en Ingeniería Electrónica). Instituto Tecnológico de Costa Rica. Escuela de Ingeniería Electrónica, 2011.Este documento presenta el estudio realizado para la implementación de una simulación del sistema circulatorio. El estudio se enfoca en el modelado matemático basado en parámetros concentrados. Durante el desarrollo del proyecto se revisaron varios modelos matemáticos existentes y se implementaron seis de ellos en la versión MATLAB/Simulink R2011a. Para construir estos modelos se utilizó la biblioteca “Cardiovascular Simulation Toolbox”. Esta biblioteca fue desarrollada en MATLAB/Simulink R14 por O. Barnea y sus colaboradores en la Universidad de Tel Aviv [1]. La biblioteca original presentaba problemas de compatibilidad con las versiones más recientes del programa, por lo que primero fue necesario reescribir la biblioteca para hacerla compatible, y luego desarrollar los modelos requeridos. Se escogió un modelo del sistema cardiovascular completo con el propósito de simular el comportamiento del sistema circulatorio en condiciones normales de salud, y en este proyecto se ajustaron los parámetros del sistema cardiovascular para poder simular la insuficiencia cardíaca sistólica, que no era parte del modelo inicial. Además se presenta un modelo sencillo para simular el comportamiento teórico de un dispositivo de asistencia ventricular. Con este modelo se implementó una simulación del corazón acoplado al VAD y se comprobó que el aparato ejerce succión en el ventrículo izquierdo

Mediation of endoevaporitic microbial communities in early replacement of gypsum by dolomite: a case study from Miocene lake deposits of the Madrid basin, Spain

Based on petrographic, mineralogical, isotope, and facies assemblage analysis, a microbial origin is established for the formation of dolomite associated with gypsum in Miocene evaporite lake deposits of the Madrid Basin, central Spain. In these deposits, dolomite is present as both intercalated carbonate beds, locally showing domal stromatolite structures between packages of selenite Christmas tree-like gypsum, and patches replacing macrocrystalline gypsum. Texture of the dolomite is characterized by crystal aggregates showing a variety of crystal sizes and morphologies, e.g., platelets, rhombs, micro-rods, and rings, whilst larger crystals are commonly spherical and/or wheat-grain shaped. Organic remains, in the form of filaments, shrubs, micro-fibrils, and strands, are also common and contain significant amounts of carbon. These textural features are also recognized in dolomite replacing gypsum, where Fe oxide and sulfide as well as celestite are ubiquitous mixed with the dolomite groundmass. The dolomite, whether primary or replacing gypsum, is poorly ordered and slightly Ca-rich, thus non stoichiometric. Stable-isotope compositions are characterized by negative values for both oxygen and carbon. Dolomite beds featuring domal stromatolites have ð18O values ranging from 22.99‰ and 23.79‰ and ð13C values ranging from 24.67‰ and 27.35‰, whilst ð13C values determined in the dolomite replacive of gypsum shows a small range of variation between 25.70‰ and 26.96‰. By contrast, ð18O values of replacive dolomite oscillate in a wider range (from 23.04‰ to 27.99‰). Formation of the dolomite was associated mainly with microbial mats, having taken place in relatively diluyed lake water. Further evaporative concentration resulted in precipitation of gypsum crystals sealing the mats and creating endoevaporitic microenvironments in which endolithic cyanobaterial activity produced extensive boring and corrosion of the gypsum crystals. Hiatuses in gypsum growth caused an intensification of the corrosion process and favored the precipitation of dolomite mediated by microbes, resulting in pervasive replacement of the sulfate

Lower Miocene gypsum palaeokarst in the Madrid Basin (central Spain): dissolution diagenesis, morphological relics and karst end-products

The Miocene sedimentary record of the Madrid Basin displays several examples of palaeokarstic surfaces sculpted within evaporite formations. One of these palaeokarstic surfaces represents the boundary between two main lithostratigraphic units, the Miocene Lower and Intermediate units of the Madrid Basin. The palaeokarst formed in lacustrine gypsum deposits of Aragonian age and corresponds to a surface palaeokarst (epikarst), further buried by terrigenous deposits of the overlying unit. Karst features are recognized up to 5.5 m beneath the gypsum surface. Exokarst and endokarst zones are distinguished by the spatial distribution of solution features, i.e. karren, dolines, pits, conduits and caves, and collapse breccias, sedimentary fills and alteration of the original gypsum across the karst profiles. The development of the gypsum palaeokarst began after drying out of a saline lake basin, as supported by recognition of root tubes, later converted to cylindrical and funnel-shaped pits, at the top of the karstic profiles. The existence of a shallow water table along with low hydraulic gradients was the main factor controlling the karst evolution, and explains the limited depth reached by both exokarst and endokarst features. Synsedimentary fill of the karst system by roughly laminated to massive clay mudstone with subordinate carbonate and clastic gypsum reflects a punctuated sedimentation regime probably related to episodic heavy rainfalls typical of arid to semi-arid climates. Duration of karstification is of the order of several thousands of years, which is consistent with previous statements that gypsum karstification can develop rapidly over geologically short time periods

Towards happiness in workplace: taking care of motivations and eliminating «digital fears»

Considerando la motivación como integrante básico de la gestión de la felicidad en el trabajo, se analiza la valoración de determinados componentes de la misma en la era digital a partir del concepto de factor motivacional e higiénico de Herzberg. Se comprobará si existe alguna asociación entre el perfil sociodemográfico del trabajador y ciertos factores a «higienizar». Se realiza un cuestionario en muestra de empresas de la Bahía de Algeciras, en la provincia de Cádiz (España), en el Estrecho de Gibraltar, zona ésta que resulta de especial relevancia estratégica al ser ruta de tránsito mundial principal de personas y de mercancías, y punto de encuentro de dos continentes, dos mares y dos culturas. Mediante cuestionario validado, se recogen las opiniones de trabajadores sobre los factores establecidos como motivadores y desmotivadores (temores). Los datos, depurados, son tratados con el programa SPSS.25. Se confirma que los factores motivacionales propuestos son altamente valorados. La falsedad de datos, el miedo a ser sustituidos en las tareas y la «despersonalización» del trabajo son las cuestiones más temidas, cuya ausencia hay que procurar. Se percibe también, asociación de determinadas variables sociodemográficas del trabajador con el grado en que se manifiestan alguno de esos temores. La originalidad principal de este trabajo estriba en que se aportan y analizan factores motivacionales e higiénicos de nueva aparición en lo laboral, que, como tales, habrán de ser gestionados.Motivation is a basic element of the ‘Happiness Management’ model at work. Its components are analyzed in the digital era under the Herzberg Theory of the motivational and hygienic factors, to verify if an association between worker sociodemographic profile and these factors is detected, which would allow the managers to «sanitize» them. In a group of companies in Algeciras Bay, province of Cádiz (Spain), in the Strait of Gibraltar, a survey has been done. This area is of special strategic relevance, being the main transit route for people and merchandise worldwide, and a meeting point for two continents, two seas and two cultures. By a validated questionnaire, the opinions of workers are collected about the issues that have been established as motivating and demotivating factors (fears). Refined data are treated with SPSS.25 program. It is confirmed that the motivational factors are highly valued. Falsity of the data, fear of being substituted at job, and depersonalization because automation are the most feared topics. An association of worker sociodemographic variables and the level to which some of these fears are manifested is found out. The main originality of this paper lies in the contribution and analysis of new factors, motivational and hygienic, of digital age in workplace, which must be managed

Valorization of chloromethanes by hydrodechlorination with metallic catalysts

The performance of Pd, Pt, Rh and Ru based catalysts in the hydrodechlorination of chloromethanes to obtain ethane and ethylene was evaluated by means of computational analysis and hydrodechlorination experiments. A computational analysis using density functional theory (DFT) was developed to obtain preliminary insight on the potential catalytic mechanisms for the reactions involved using palladium, platinum, rhodium and ruthenium metallic clusters. Stable catalytic intermediates were obtained by quantum-chemical calculations in the hydrodechlorination of dichloromethane on Pd6and Rh6clusters, presenting [rad][rad]CH2and [rad]CH3radicals and C2H4, C2H6and CH4products. On the contrary, it was not possible to obtain all these stable intermediates using Pt6and Ru6clusters. Theoretical analysis revealed lower desorption energies for ethane and ethylene products in Pd6than in Rh6clusters, what indicates a favorable selectivity of Pd-based catalyst for desired C2products. Then, carbon supported catalysts containing these four metals were prepared and experimentally evaluated in the hydrodechlorination of dichloromethane (DCM) and trichloromethane (TCM) at low H2excess and a reaction temperature range of 150-400 °C. In agreement with computational results, in experimental tests, the Pd based catalyst showed the best performance for the hydrodechlorination of chloromethanes to obtain C2products, followed by Rh, Ru and Pt have a poor performance, in special Pt based catalyst, which shows almost no selectivity to C2products. This computational and experimental study emphasizes, for the first time, the good performance (high activity and selectivity) of Pd carbon supported catalysts in the valorization of chloromethane compounds to obtain C2hydrocarbon productsThe authors gratefully acknowledge financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) through the project CTM 2014-53008 and to the “Centro de Computación Científica de la Universidad Autónoma de Madrid” for computational facilitie

Density Functional Theory Analysis of Dichloromethane andHydrogen Interaction with Pd Clusters: First Step toSimulate Catalytic Hydrodechlorination

A density functional theory (DFT) analysis hasbeen conducted for the gas-phase hydrodechlorination (HDC) ofdichloromethane (DCM) with palladium catalyst to achieve abetter knowledge of the reaction mechanism involved in the HDCprocess, which constitutes an emerging technology for the treat-ment of organochlorinated contaminants. The computationalstudy included the effect of size, oxidation state, and spin config-uration of Pd cluster on the adsorption of H2and DCM reactantson the catalyst surface. Calculations described the activation of H2by Pd clusters through a dissociative adsorption with low enthalpy values. In addition, partially and fully dissociated DCMintermediates on Pd surface were predicted by DFT calculations. Remarkably, the dissociative adsorption of DCM on Pd active sitesoccurs via the scission of C Cl bonds, promoted by the formation of C Pd linkages, implying high adsorption enthalpy. Thecomputational results showed that DCM can be also molecularly adsorbed on both zerovalent and electrodeficient Pd species.However, the nondissociative adsorption of DCM over electrodeficient Pd cluster is remarkably favored in energy, with adsorptionenthalpies (∼ 50 kcal/mol) corresponding to chemisorption. Current theoretical evidence explained the deactivation of Pd/ACcatalyst as a consequence of the selective poisoning of electrodeficient Pd active centers by chlorinated hydrocarbons, in goodagreement with our previous experimental findingsWe are grateful to the Spanish “Ministerio de Ciencia e Innovacion”and“Comunidad de Madrid ”for financial support (CTQ2008-04751, CTQ2008-05641, and S2009/PPQ-1545). We are also very grateful to “Centro de Computacion Científica de la Universidad Aut onoma de Madrid” for computational facilitie

Hydrodechlorination of chloromethanes with Pd on activated carbon catalysts for the treatment of residual gas streams

Laboratory-prepared Pd/C catalysts have been investigated in the deep gas-phase hydrodechlorination (HDC) of monochloromethane (CH3Cl), dichloromethane (CH2Cl2) and trichloromethane (CHCl3). The catalysts were found to be active in HDC, the reactivity following the order CHCl3 > CH2Cl2 > CH3Cl. Selectivities to non-chlorinated compounds were found to be higher than 90% in most cases. The results obtained with the catalyst prepared from PdCl2 suggest that all the reaction products are primary products. The CH4, CH3Cl and CH2Cl2 come from the hydrogenation of the corresponding adsorbed chloride radical, while hydrocarbons of more than one carbon atoms are formed by reaction and subsequent hydrodechlorination of two radicals adsorbed in neighbouring active centers. The catalyst undergoes a significant deactivation which appears to be due to the poisoning of active centers with chlorinated hydrocarbons. The use of Pd(NO3)2 as Pd precursor leads to a decrease in the activity due to its lower Pd dispersion and a lower proportion of electrodeficient Pd speciesThe authors gratefully acknowledge financial support from the Spanish MEC through the project CTQ2005-07579. M.A. Álvarez Montero also wishes to thank the Spanish MEC for her research gran

Rewiring Vascular Metabolism Prevents Sudden Death due to Aortic Ruptures-Brief Report.

The goal of this study was to determine whether boosting mitochondrial respiration prevents the development of fatal aortic ruptures triggered by atherosclerosis and hypertension. Ang-II (angiotensin-II) was infused in ApoE (Apolipoprotein E)-deficient mice fed with a western diet to induce acute aortic aneurysms and lethal ruptures. We found decreased mitochondrial respiration and mitochondrial proteins in vascular smooth muscle cells from murine and human aortic aneurysms. Boosting NAD levels with nicotinamide riboside reduced the development of aortic aneurysms and sudden death by aortic ruptures. Targetable vascular metabolism is a new clinical strategy to prevent fatal aortic ruptures and sudden death in patients with aortic aneurysms.This study was supported by the Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI16/188, PI19/855), the European Regional Development Fund (ERDF), and the European Commission through H2020-EU.1.1 and European Research Council grant ERC-2016-StG 715322-EndoMitTalk. This work was partially supported by Comunidad de Madrid (S2017/ BMD-3867 RENIM-CM), co-financed by European Structural and Investment Fund. M. Mittelbrunn is supported by the Miguel Servet Program (CP 19/014, Fundación de Investigación del Hospital 12 de Octubre). J. Oller and E. Gabandé-Rodríguez are supported by Juan de la Cierva (IJC2019-040152-I and IJC2018-036850-I respectively). Support was also provided by Ministerio de Ciencia e Innovación grants (RTI2018-099246-B-I00, Comunidad de Madrid and Fondo Social Europeo funds (AORTASANA-CM; J. Miguel Redondo), J. Miguel Redondo was also funded by Fundación La Caixa (HR18-00068), The Marfan Foundation USA and the CIBER-CV of Ministerio de Ciencia e Innovación (CB16/11/00264).S

Superhydrophobic supported Ag-NPs@ZnO-nanorods with photoactivity in the visible range

In this article we present a new type of 1D nanostructures consisting of supported hollow ZnO nanorods (NRs) decorated with Ag nanoparticles (NPs). The 3D reconstruction by high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) electron tomography reveals that the Ag NPs are distributed along the hollow interior of the ZnO NRs. Supported and vertically aligned Ag-NPs@ZnO-NRs grow at low temperature (135 °C) by plasma enhanced chemical vapour deposition on heterostructured substrates fabricated by sputtered deposition of silver on flat surfaces of Si wafers, quartz slides or ITO. The growth mechanisms of these structures and their wetting behavior before and after visible light irradiation are critically discussed. The as prepared surfaces are superhydrophobic with water contact angles higher than 150°. These surfaces turn into superhydrophilic with water contact angles lower than 10° after prolonged irradiation under both visible and UV light. The evolution rate of the wetting angle and its dependence on the light characteristics are related to the nanostructure and the presence of silver embedded within the ZnO NRs. ÂEuropean Union NMP3-CT-2006- 032583Ministerio de Ciencia e Innovación MAT2010-21228, MAT2010-18447, CSD2008-00023Junta de Andalucía P09-TEP-5283, CTS-518