More is Different: Modern Computational Modeling for Heterogeneous Catalysis

La combinació d'observacions experimentals i estudis de la Density Functional Theory (DFT) és un dels pilars de la investigació química moderna. Atès que permeten recopilar informació física addicional d'un sistema químic, difícilment accessible a través de l'entorn experimental, aquests estudis es fan servir àmpliament per modelar i predir el comportament d'una gran varietat de compostos químics en entorns únics. A la catàlisi heterogènia, els models DFT s'utilitzen habitualment per avaluar la interacció entre els compostos moleculars i els catalitzadors, vinculant aquestes interpretacions amb els resultats experimentals. Tanmateix, l'alta complexitat trobada tant als escenaris catalítics com a la reactivitat, implica la necessitat de metodologies sofisticades que requereixen automatització, emmagatzematge i anàlisi per estudiar correctament aquests sistemes. Aquest treball presenta el desenvolupament i la combinació de múltiples metodologies per avaluar correctament la complexitat d'aquests sistemes químics. A més, aquest treball mostra com s'han utilitzat les tècniques proporcionades per estudiar noves configuracions catalítiques d'interès acadèmic i industrial.La combinación de observaciones experimentales y estudios de la Density Functional Theory (DFT) es uno de los pilares de la investigación química moderna. Dado que permiten recopilar información física adicional de un sistema químico, difícilmente accesible a través del entorno experimental, estos estudios se emplean ampliamente para modelar y predecir el comportamiento de una gran variedad de compuestos químicos en entornos únicos. En la catálisis heterogénea, los modelos DFT se emplean habitualmente para evaluar la interacción entre los compuestos moleculares y los catalizadores, vinculando estas interpretaciones con los resultados experimentales. Sin embargo, la alta complejidad encontrada tanto en los escenarios catalíticos como en la reactividad, implica la necesidad de metodologías sofisticadas que requieren de automatización, almacenamiento y análisis para estudiar correctamente estos sistemas. Este trabajo presenta el desarrollo y la combinación de múltiples metodologías con el objetivo de evaluar correctamente la complejidad de estos sistemas químicos. Además, este trabajo muestra cómo las técnicas proporcionadas se han utilizado para estudiar nuevas configuraciones catalíticas de interés académico e industrial.The combination of Experimental observations and Density Functional Theory studies is one of the pillars of modern chemical research. As they enable the collection of additional physical information of a chemical system, hardly accessible via the experimental setting, Density Functional Theory studies are widely employed to model and predict the behavior of a diverse variety of chemical compounds under unique environments. Particularly, in heterogeneous catalysis, Density Functional Theory models are commonly employed to evaluate the interaction between molecular compounds and catalysts, lately linking these interpretations with experimental results. However, high complexity found in both, catalytic settings and reactivity, implies the need of sophisticated methodologies involving automation, storage and analysis to correctly study these systems. Here, I present the development and combination of multiple methodologies, aiming at correctly asses complexity. Also, this work shows how the provided techniques have been actively used to study novel catalytic settings of academic and industrial interest

Estudio computacional de radicales orgánicos de interés tecnológico en magnetismo basado en moléculas

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2017, Tutora: Mercè Deumal SoléA new magnetic crystal composed of an anthranol/anthroxyl unit has been synthesized and characterized.[1] The crystal, which is composed by anthroxyl radicals, appears to undergo a magnetic phase transition when it reaches a temperature of ca. 100 K. The anthranol/anthroxyl pairs found in the 100 K and 200 K structures (see Figure I) characterized by X-rays, show large differences in the position of the central hydrogen between the two oxygens in each pair. While in the structure at 100 K the hydrogen is bonded to the oxygen of the anthranol molecule, in the structure at 200 K the hydrogen seems to be delocalized between the two oxygens of the pair, thus forming two semi-radicals. Upon phase transition, a proton coupled electron transfer (PCET) reaction takes place.This work performs a computational study on the PCET reaction taking place inside the crystal as well as the topological changes leading the magnetic transition that occurs at ca. 100 K. The study of the reaction is carried out in the gas phase through different anthranol/anthroxyl pairs extracted from the X-Ray crystal data. A study of the energies, the topology and the differences between the anthranol/anthroxyl pairs in the gas phase, as well as a search of the transition state for a better understanding of the reaction in the crystal is carried out.The energy barrier for the proton coupled electron transfer (PCET) in gas phase has found to be 11.11 kcal mol-1. It is believed that accounting for the anthranol/anthroxyl solid state environment would lead to a decrease of this barrier. For a better characterization of the magnetic behavior of the system, a study of the distribution of spin density on both structures Figure I (a) and (b), is performed, in which the semi-radical nature of the 200 K structure can be observed. To carry out the magnetic analysis, different pairs of anthranol/anthroxyl dimers extracted from the two X-ray diffraction structures, at 100 K and 200 K, will be used. The magnetic coupling interaction of these dimers is calculated to be able to build the magnetic topology of the crystal. Once known, magnetic models are used to calculate the magnetic susceptibility of both structures and compare them with the value obtained experimentally. The results obtained suggest that the structure at 100 K behaves diamagnetically. At 200 K, however, a dynamic behavior is observed since the structure found experimentally could be a statistical average of a set of structures belonging to the reaction path. Finally, we have investigated whether electron-donor or withdrawing substituents can give rise to new anthranol/anthroxyl pairs with enhanced proton coupled electron transfer capabilities

Barreras comunicativas en la atención sanitaria a la población inmigrante = Communication barriers in health to immigrants

Resumen: España tiene una elevada proporción de población inmigrante e igualmente recibe un elevado número de turistas; ambos factores suponen la atención sanitaria de población con barrera idiomática y la repercusión que ello tiene en la atención prestada. Objetivos: El objetivo general que se pretende es conocer las principales dificultades que nos encontramos en la prestación de atención sanitaria a la población inmigrante con idioma diferente. Métodos: Revisión bibliográfica narrativa en las bases de datos de Cuiden, ScienceDirect, CINAHL y MEDLINE utilizando los descriptores “comunicación” and “inmigrante” en el periodo comprendido entre 2009 y 2014 y desarrollados en el contexto sanitario español. Resultados: Las principales categorías de análisis emergentes fueron: acceso y utilización del Sistema Nacional de Salud, barreras lingüísticas y medios facilitadores, diferencias culturales, problemas psicosociales de la población inmigrante y formación de profesionales sanitarios en aspectos culturales e idiomáticos; todas ellas interrelacionadas con los aspectos comunicativos en el proceso de atención. Conclusiones: La barrera idiomática presente entre los profesionales sanitarios y la población inmigrante interfiere en la calidad de la atención prestada desde el acceso y utilización de los servicios sanitarios hasta la continuidad de cuidados y abordaje de problemas psicosociales, siendo necesaria una formación lingüística y cultural de los profesionales sanitarios.Palabras clave: Atención, barreras, calidad, comunicación, idioma, inmigrantes, saludAbstract: Spain has a high proportion of immigrants and also receives a high number of tourists; then his professionals have to attend a population with communication barrier and the impact that this has on the care provided. Objectives: The general objective is to know the main difficulties we encountered in the provision of health care to immigrants with different language. Methods: Literature review in the databases Cuiden, ScienceDirect, CINAHL and MEDLINE using the descriptors "Communication" and "immigrant" in the period between 2009 and 2014 and developed in the context of Spanish Health System. Results: The main categories of emerging analysis were: access to and use of the National Health System, linguistic barriers and facilitators media, cultural differences, psychosocial problems of the immigrant population and training of health professionals in cultural and language issues; all interrelated with the communicative aspects in the care process. Conclusions: The language barrier between healthcare professionals and immigrants interferes in the quality of care provided from the access and use of health services to the continuity of care and addressing psychosocial issues, language and cultural training are necessary in health professionals.Keywords: Barriers, care, communications, health, immigrans, language, qualit

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.

An embedding technique to determine ττ backgrounds in proton-proton collision data

An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

Peer reviewe

Search for Physics beyond the Standard Model in Events with Overlapping Photons and Jets

Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with hadrons. The analyzed proton-proton collision data were collected by the CMS experiment at the LHC, in 2016 at root s = 13 TeV, and correspond to an integrated luminosity of 35.9 fb(-1). The spectra of total transverse hadronic energy of candidate events are examined for deviations from the standard model predictions. No statistically significant excess is observed over the expected background. The first cross section limits on new physics processes resulting in such events are set. The results are interpreted as upper limits on the rate of gluino pair production, utilizing a simplified stealth supersymmetry model. The excluded gluino masses extend up to 1.7 TeV, for a neutralino mass of 200 GeV and exceed previous mass constraints set by analyses targeting events with isolated photons.Peer reviewe

Measurement of b jet shapes in proton-proton collisions at root s=5.02 TeV

We present the first study of charged-hadron production associated with jets originating from b quarks in proton-proton collisions at a center-of-mass energy of 5.02 TeV. The data sample used in this study was collected with the CMS detector at the CERN LHC and corresponds to an integrated luminosity of 27.4 pb(-1). To characterize the jet substructure, the differential jet shapes, defined as the normalized transverse momentum distribution of charged hadrons as a function of angular distance from the jet axis, are measured for b jets. In addition to the jet shapes, the per-jet yields of charged particles associated with b jets are also quantified, again as a function of the angular distance with respect to the jet axis. Extracted jet shape and particle yield distributions for b jets are compared with results for inclusive jets, as well as with the predictions from the pythia and herwig++ event generators.Peer reviewe

Calibration of the CMS hadron calorimeters using proton-proton collision data at root s=13 TeV

Methods are presented for calibrating the hadron calorimeter system of theCMSetector at the LHC. The hadron calorimeters of the CMS experiment are sampling calorimeters of brass and scintillator, and are in the form of one central detector and two endcaps. These calorimeters cover pseudorapidities vertical bar eta vertical bar ee data. The energy scale of the outer calorimeters has been determined with test beam data and is confirmed through data with high transverse momentum jets. In this paper, we present the details of the calibration methods and accuracy.Peer reviewe