Uniform and strict persistence in monotone skew-product semiflows with applications to non-autonomous Nicholson systems

Producción CientíficaWe determine sufficient conditions for uniform and strict persistence in the case of skew-product semiflows generated by solutions of non-autonomous families of cooperative systems of ODEs or delay FDEs in terms of the principal spectrums of some associated linear skew-product semiflows which admit a continuous separation. Our conditions are also necessary in the linear case. We apply our results to a noncooperative almost periodic Nicholson system with a patch structure, whose persistence turns out to be equivalent to the persistence of the linearized system along the null solution.MINECO/FEDER MTM2015-6633

Is uniform persistence a robust property in almost periodic models? A well-behaved family: almost periodic Nicholson systems

Producción CientíficaUsing techniques of non-autonomous dynamical systems, we completely characterize the persistence properties of an almost periodic Nicholson system in terms of some numerically computable exponents. Although similar results hold for a class of cooperative and sublinear models, in the general nonautonomous setting one has to consider persistence as a collective property of the family of systems over the hull: the reason is that uniform persistence is not a robust property in models given by almost periodic differential equations.MINECO / FEDER grant MTM2015-66330-

Persistence in non-autonomous quasimonotone parabolic partial functional differential equations with delay

Producción CientíficaThis paper provides a dynamical frame to study non- autonomous parabolic partial differential equations with finite delay. Assuming monotonicity of the linearized semiflow, conditions for the existence of a continuous separation of type II over a minimal set are given. Then, practical criteria for the uniform or strict persistence of the systems above a minimal set are obtained.MINECO/FEDER grant MTM2015-66330-PEuropean Commission under project H2020-MSCA-ITN-2014 643073 CRITIC

Interaction of electrons and positrons with molecular systems of biological interest

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departaemnto de Química. Fecha de lectura: 09-05-2014The aim of this thesis is to study electron and positron interactions with biologically relevant molecules. The study starts with a theoretical investigation on electron collisions with the non-polar targets anthracene and pyrazine and the polar molecules hydrogen-cyanide and pyrimidine, in the gas-phase. Integral and differential electron-molecule cross sections over a broad energy range, typically from 0.1 eV up to 10 keV, are derived using either the R-matrix method or a single-centre expansion-symmetry adapted approach at low energies (below 10 eV), and a screening corrected form of the independent atom model at higher energies. After a critical comparison with the available experimental sources, theoretical self-consistent electron collisional data sets are recommended for the aforementioned molecules. Furthermore, this combined approach has been adapted to study positron-molecule collisions. In particular, positron scattering cross sections by pyrimidine are for the first time reported. The calculated interaction parameters find their main practical application in energy deposition models. Accordingly, this thesis also presents a study of electron and positron transport in water in the liquid state using a custom-programmed molecular-level Monte Carlo code, the Low-Energy Particle Track Simulation. Particular emphasis is given to the low-energy processes which are known to be determinant in radiation damage. In addition, a milestone in the radiation damage field is the investigation of how the fundamental mechanisms of damage are affected and modified under conditions closer to cell. Within this context, an experimental work has been carried out to investigate damage to DNA induced by X-rays and low-energy electrons (LEEs) under standard ambient temperature and pressure (SATP). In particular, thin films of the nucleoside thymidine have been irradiated under dry nitrogen and oxygen. Afterwards, a more complex target, plasmid DNA, has been irradiated under different humidity levels up to solvation. These measurements indicate a much higher efficiency for LEEs relative to X-rays in causing DNA damage under both a hydrated and aerobic environment. This way, this work aims to shed a light on the indirect effects of LEEs. Finally, based on this experimental work, a new experimental apparatus has been designed and constructed which will permit in the future to validate energy deposition models in the condensed phas

Global and cocycle attractors for non-autonomous reaction-diffusion equations. The case of null upper Lyapunov exponent

In this paper we obtain a detailed description of the global and cocycle attractors for the skew-product semiflows induced by the mild solutions of a family of scalar linear-dissipative parabolic problems over a minimal and uniquely ergodic flow. We consider the case of null upper Lyapunov exponent for the linear part of the problem. Then, basically two different types of attractors can appear, depending on whether the linear coefficient in the equations determines a bounded or an unbounded associated real cocycle. In the first case (the one for periodic equations), the structure of the attractor is simple, whereas in the second case (which happens in aperiodic equations), the attractor is a pinched set with a complicated structure. We describe situations in which the attractor is chaotic in measure in the sense of Li-Yorke. Besides, we obtain a non-autonomous discontinuous pitchfork bifurcation scenario for concave equations, applicable for instance to a linear-dissipative version of the Chafee-Infante equation.Ministerio de Economía y CompetitividadFondo Europeo de Desarrollo RegionalEuropean CommissionJunta de Andalucí

La D.O. Ribera de Duero: un distrito en formación

Este trabajo se centra en el estudio de la D.O. Ribera del Duero como un distrito industrial. Esta denominación de origen es una de las más famosas en España, y ahora se está dando a conocer por todo el mundo debido a sus exportaciones. La D.O. Ribera del Duero se trata de una agrupación de bodegas que realizan una misma actividad productiva, la producción de vino, sobre todo tinto. En el siguiente documento se podrá ver un estudio de todos los requisitos necesarios que debe tener una aglomeración de empresas para poder considerarla como distrito industrial. Se analizarán los agentes, el efecto distrito y las economías externas que se deberían dar si de verdad fuese un distrito industrial y, con ello, se verán claramente las carencias que sufre la D.O. Ribera del Duero para ser considerada un distrito industrial.This project focuses on the study of the D. O. Ribera del Duero as an industrial district. This denimination is one of the most famous in Spain and now it is also becoming well- known all over the world due to its exports. D. O. Ribera del Duero is an association of wineries that carry out the same productive activity, the production of wine, especially red wine. In the following document you will be able to see a study of the necessary requirements that a group of companies must meet to be considered an industrial district. Several factors will be analyzed such as the agents, the district effect and the external economies that there should be if it really was an industrial district, and this way, you will clearly see the lacks the D. O. Ribera del Duero has to be considered an industrial district.Departamento de Organización de Empresas y Comercialización e Investigación de MercadosGrado en Administración y Dirección de Empresa

Asymptotic Behaviour for a Class of Non-monotone Delay Differential Systems with Applications

The paper concerns a class of n-dimensional non-autonomous delay differential equations obtained by adding a non-monotone delayed perturbation to a linear homogeneous cooperative system of ordinary differential equations. This family covers a wide set of models used in structured population dynamics. By exploiting the stability and the monotone character of the linear ODE, we establish sufficient conditions for both the extinction of all the populations and the permanence of the system. In the case of DDEs with autonomous coefficients (but possible time-varying delays), sharp results are obtained, even in the case of a reducible community matrix. As a sub-product, our results improve some criteria for autonomous systems published in recent literature. As an important illustration, the extinction, persistence and permanence of a non-autonomous Nicholson system with patch structure and multiple time-dependent delays are analysed.Ministerio de Economía, Industria y Competitividad /FEDER (MTM2015-66330)Fundaçao para a Ciencia e a Tecnologia under project UID/MAT/-04561/201

Inhibition of pneumococcal choline-binding proteins and cell growth by esters of bicyclic amines

Streptococcus pneumoniae is one of the major pathogens worldwide. The use of currently available antibiotics to treat pneumococcal diseases is hampered by increasing resistance levels; also, capsular polysaccharide-based vaccination is of limited efficacy. Therefore, it is desirable to find targets for the development of new antimicrobial drugs specifically designed to fight pneumococcal infections. Choline-binding proteins are a family of polypeptides, found in all S. pneumoniae strains, that take part in important physiologic processes of this bacterium. Among them are several murein hydrolases whose enzymatic activity is usually inhibited by an excess of choline. Using a simple chromatographic procedure, we have identified several choline analogs able to strongly interact with the choline-binding module (C-LytA) of the major autolysin of S. pneumoniae. Two of these compounds (atropine and ipratropium) display a higher binding affinity to C-LytA than choline, and also increase the stability of the protein. CD and fluorescence spectroscopy analyses revealed that the conformational changes of C-LytA upon binding of these alkaloids are different to those induced by choline, suggesting a different mode of binding. In vitro inhibition assays of three pneumococcal, choline-dependent cell wall lytic enzymes also demonstrated a greater inhibitory efficiency of those molecules. Moreover, atropine and ipratropium strongly inhibited in vitro pneumococcal growth, altering cell morphology and reducing cell viability, a very different response than that observed upon addition of an excess of choline. These results may open up the possibility of the development of bicyclic amines as new antimicrobials for use against pneumococcal pathologies

Ten Things Every Psychologist Should Know About Treating Psychological Disorders in Victims of Terrorism

Terrorism remains one of the most serious global problems, affecting a very large number of people, a signifi cant percentage of whom can suffer psychological disorders arising from a terrorist attack. The purpose of this article is to describe the current state of scientifi knowledge about these psychological disorders and their treatment. Method: Systematic narrative or meta-analytical reviews of the scientifi literature on the subject published between 2010 and 2020 were searched for in PsycINFO, MEDLINE, and PTSDpubs. Results: The search located 16 systematic reviews whose findings were analyzed, leading to ten conclusions about the most common psychological disorders and their progression, the type and percentage of victims who will be most affected by them, and the most effective and useful treatments for those disorders during the various phases following an attack. Conclusions: After a terrorist attack, both direct and indirect victims will need shortand mid-term psychological care and follow up. Direct victims, the direct relatives of any deceased, and other victims signifi cantly exposed to the attack or its consequences, will also need long- and very long-term care and follow up. Currently, trauma-focused cognitive-behavioral therapies are the treatment of choice for victims in the rescue, recovery, and returnto-life phases