Els paisatges del Montgó i del seu entorn. Aspectes geomorfològics i evolució quaternària.

Maria Pilar Fumanal - No aparece en el registro de usuarios

The quest for rationalizing the magnetism in purely organic semiquinone-bridged bisdithiazolyl molecular magnets

Semiquinone-bridged bisdithiazolyl-based radicals (XBBO) are appealing purely organic magnetic building blocks for the synthesis of new functional materials. Remarkably, for the phenyl-derivative PhBBO, the rationalization of its magnetism becomes a proof of concept that DFT can dramatically fail to evaluate JAB magnetic interactions between purely organic radical pairs. Instead, wavefunction-based methods are required. Once JAB's are fully characterized, the magnetic topology of PhBBO is disclosed to consist of ferromagnetic FM π-stacks that are very weakly coupled (by FM and AFM JAB interactions). The magnetic susceptibility χT(T) and magnetization M(H) of PhBBO are then calculated using a first-principles bottom-up approach. The study of the unit cell contraction upon cooling from room temperature to zero-Kelvin is relevant to propose a suitable model for the phase transition that occurs at 4.5 K. A simplistic picture tells us that the antiparallel-aligned 1D-FM-chains convert into domains of weakly either FM- or AFM-coupled 1D-FM-chains. Accordingly, the presence of these domains may introduce geometrical spin frustration below 4.5 K

Origin of bistability in the butyl-substituted spirobiphenalenyl-based neutral radical material

One of the most remarkable bistable materials reported so far is made of pi dimers of a butyl-substituted spirobiphenalenyl boron radical (butyl-SBP). The phase transition of this material, which is accompanied by changes in its optical, conductive, and magnetic properties, occurs with a hysteretic loop 25 K wide centered at 335 K. Herein, a computational study is presented aimed at deciphering the origin of this hysteresis. The phase transition of butyl-SBP consists of a spin transition of the constituent pi dimers coupled with an order-disorder transition involving the butyl chains linked to the nitrogen atoms of the superimposed phenalenyl rings of the pi dimer. Below 335 K, the terminal methyl group of the butyl chains adopts a gauche conformation with respect to the methylene unit bonded to the nitrogen atom. Above 335 K, the methyl group is in an anti conformation and exhibits dynamic disorder. The gauche -> anti conformational rearrangement triggers the spin transition of the pi dimers and is responsible for the hysteretic behavior of butyl-SBP. Specifically, the onset of the phase transition in the heating mode, and thus, the width of the hysteresis loop, are governed by the high energy cost and strong structural cooperative effects associated with this conformational change. Our results show that coupling a spin switch with a conformational switch in a molecular crystal provides a promising strategy in the design of new bistable materials

Thermal spin crossover in Fe(ii) and Fe(iii). Accurate spin state energetics at the solid state

The thermal spin crossover (SCO) phenomenon refers to an entropy-driven spin transition in some materials based on d6-d9 transition metal complexes. While its molecular origin is well known, intricate SCO behaviours are increasingly common, in which the spin transition occurs concomitantly to e.g. phase transformations, solvent absorption/desorption, or order-disorder processes. The computational modelling of such cases is challenging, as it requires accurate spin state energies in the solid state. Density Functional Theory (DFT) is the best framework, but most DFT functionals are unable to balance the spin state energies. While a few hybrid functionals perform better, they are still too expensive for solid-state minima searches in moderate-size systems. The best alternative is to dress cheap local (LDA) or semi-local (GGA) DFT functionals with a Hubbard-type correction (DFT+U). However, the parametrization of U is not straightforward due to the lack of reference values, and because ab initio parametrization methods perform poorly. Moreover, SCO complexes undergo notable structural changes upon transition, so intra- and inter-molecular interactions might play an important role in stabilizing either spin state. As a consequence, the U parameter depends strongly on the dispersion correction scheme that is used. In this paper, we parametrize U for nine reported SCO compounds (five based on FeII, 1-5 and four based on FeIII, 6-9) when using the D3 and D3-BJ dispersion corrections. We analyze the impact of the dispersion correction treatments on the SCO energetics, structure, and the unit cell dimensions. The average U values are different for each type of metal ion (FeIIvs. FeIII), and dispersion correction scheme (D3 vs. D3-BJ) but they all show excellent transferability, with mean absolute errors (MAE) below chemical accuracy (i.e. MAE <4 kJ mol−1). This enables a better description of SCO processes and, more generally, of spin state energetics, in materials containing FeII and FeIII ions

Combinations of Affinity Functions for Different Community Detection Algorithms in Social Networks

Social network analysis is a popular discipline among the social and behavioural sciences, in which the relationships between different social entities are modelled as a network. One of the most popular problems in social network analysis is finding communities in its network structure. Usually, a community in a social network is a functional sub-partition of the graph. However, as the definition of community is somewhat imprecise, many algorithms have been proposed to solve this task, each of them focusing on different social characteristics of the actors and the communities. In this work we propose to use novel combinations of affinity functions, which are designed to capture different social mechanics in the network interactions. We use them to extend already existing community detection algorithms in order to combine the capacity of the affinity functions to model different social interactions than those exploited by the original algorithms

Difuminando niveles: desde la normativa al aula

Este Trabajo Fin de Máster es un análisis crítico y reflexivo a partir de dos actividades realizadas durante el Máster en profesorado: la memoria del Prácticum I y la elaboración de la Unidad Didáctica del módulo de Formación y Orientación Laboral. El nexo de unión entre los dos trabajos académicos seleccionados son los niveles de concreción curricular. El objetivo del trabajo es demostrar que se han alcanzado las competencias que me capacitan para ejercer la docencia. Consta de cuatro epígrafes, en el primero se realiza una breve introducción sobre la Formación Profesional en España. En el segundo punto se pone de manifiesto la importancia de trabajar por competencias, tanto en la Formación Profesional como en el Máster en profesorado. En el tercer punto se realiza una reflexión crítica de las actividades académicas seleccionadas con las competencias adquiridas del Máster y se exponen dos propuestas innovadoras para mejorar la docencia teniendo en cuenta las Tecnologías de la Información y de la Comunicación. Por último, se termina concluyendo la necesidad de aprender a aprender y la importancia de una formación a lo largo de la vida, tanto de los docentes como del alumnado.<br /

Towards the tailored design of benzotriazinyl-based organic radicals displaying a spin transition

The mechanism of the phase transition of 1-phenyl-3-trifluoromethyl- 1,4-dihydrobenzo[e][1,2,4]triazin-4-yl (1), the first reported triazinyl radical to present such a feature, is unveiled. In so doing, we identify the key ingredients that are crucial to enable the phase transition in this family of radicals, and how those can be exploited by a rational design of the spin-carrying units

Fisioterapia en un caso de quemadura eléctrica en la mano

Estudio intrasujeto n=1 con modelo AB, de tipo caso clínico de intervención en fisioterapia. Varón que sufrió quemadura eléctrica de 2º grado en la mano izquierda en horario de trabajo. Es valorado y tratado con fisioterapia

Replacement of Metaphylactic Antimicrobial Therapy by Oral Administration of Ligilactobacillus salivarius MP100 in a Pig Farm

Antibiotic use in swine production contributes to the emergence and spread of resistant bacteria, which poses a threat on human health. Therefore, alternative approaches must be developed. The objective of this work was the characterization of the probiotic properties of a Ligilactobacillus salivarius strain isolated from sow's milk and its application as an inoculated fermented feed to pregnant sows and piglets. The study was carried in a farm in which metaphylactic use of antimicrobials (including zinc oxide) was eliminated at the time of starting the probiotic intervention, which lasted for 2 years. Feces from 8-week-old piglets were collected before and after the treatment and microbiological and biochemical analyses were performed. The procedure led to an increase in the concentrations of clostridia and lactobacilli-related bacteria. Parallel, an increase in the concentration of butyrate, propionate and acetate was observed and a notable reduction in the presence of antibiotic resistant lactobacilli became apparent. In conclusion, replacement of antimicrobials by a microbiota-friendly approach was feasible and led to positive microbiological and biochemical changes in the enteric environment

Una apuesta desde la docencia: la comunicación intercultural

El Trabajo Fin de Máster (TFM) a exponer a continuación, muestra mi transcurso por el Máster Universitario en Profesorado de Educación Secundaria Obligatoria, Bachillerato, Formación Profesional y Enseñanzas de Idiomas, Artísticas y Deportivas. Así, ofrezco un análisis y reflexión sobre la consecución de las distintas competencias obtenidas tras la superación del Máster. En primer lugar, redacto una introducción donde me presento y planteo un encuadre del Sistema Educativo, así como de la Formación Profesional, la Educación Infantil y la Educación Primaria. Posteriormente, explico las competencias adquiridas y presento dos de los proyectos realizados durante el Máster, con el propósito de hacer visible la adquisición de dichas competencias a través de la elaboración de ambos. También expongo una reflexión donde profundizo, en mayor medida, sobre los aprendizajes obtenidos, así como planteo una posible propuesta educativa. Por último, durante la conclusión reflejo mi visión del Máster y las inquietudes surgidas tras él.<br /