Results on parabolic equations related to some Caffarelli-Kohn-Nirenberg inequalities

We study existence and non existence results for a class of parabolic problems related to some Caffarelli Kohn Nirenberg inequalities, which include the classical Hardy inequality. The paper starts by the results of Baras and Goldstein concerning existence and blow-up for the solution to the heat equation with a critical potential, results which use as essential tool the Hardy inequality

Semilinear problems for the fractional laplacian with a singular nonlinearity

The aim of this paper is to study the solvability of the problem (-Δ)s u = F(x,u) := λ f(x)/uγ + Mup in ω u > 0 in ω, u = 0 in RN \ ω, where Ω is a bounded smooth domain of RN, N > 2s, M ε {0, 1}, 0 0, λ > 0, p > 1 and f is a nonnegative function. We distinguish two cases: - For M = 0, we prove the existence of a solution for every γ > 0 and λ > 0. A1 - For M = 1, we consider f ≡ 1 and we find a threshold ∧ such that there exists a solution for every 0 ∧Work partially supported by project MTM2013-40846-P MINECO. The third author is also supported for the grant BES-2011-044216 associated to MTM2010-1812

Patentades unes fosfines per processos de Química Verda

Els catalitzadors són substàncies que augmenten la velocitat de les reaccions químiques en les quals participen i que són utilitzats en la majoria dels productes químics manufacturats. D'entre els més utilitzats es troben els que es basen en metalls de transició. La UAB ha patentat uns nous lligands fosfina sintetitzats en una tesi doctoral que permeten preparar un nou tipus de catalitzadors per processos de Química Verda. Aquests catalitzadors són solubles en aigua, la qual cosa permet la seva reutilització, i són més efectius que els descrits prèviament.Los catalizadoresson sustancias que aumentan la velocidad de las reacciones químicas en las que participan y que son utilizados en la mayoría de los productos químicos manufacturados. De entre los más utilizados se encuentran los basados en metalesde transición. La UAB ha patentado unos nuevos ligandos fosfina sintetizados en una tesis doctoral que permiten preparar un nuevo tipo de catalizadores por procesos de Química Verde. Estos catalizadores son solubles en agua, lo cual permite su reutilización, y son más efectivos que los descritos previamente

Phase Transformations in the CeO2-Sm2O3System : A Multiscale Powder Diffraction Investigation

The structure evolution in the CeO2-Sm2O3system is revisited by combining high resolution synchrotron powder diffraction with pair distribution function (PDF) to inquire about local, mesoscopic, and average structure. The CeO2fluorite structure undergoes two phase transformations by Sm doping, first to a cubic (C-type) and then to a monoclinic (B-type) phase. Whereas the C to B-phase separation occurs completely and on a long-range scale, no miscibility gap is detected between fluorite and C-type phases. The transformation rather occurs by growth of C-type nanodomains embedded in the fluorite matrix, without any long-range phase separation. A side effect of this mechanism is the ordering of the oxygen vacancies, which is detrimental for the application of doped ceria as an electrolyte in fuel cells. The results are discussed in the framework of other Y and Gd dopants, and the relationship between nanostructuring and the above equilibria is also investigated

Effect of Shot Peening on Oxidation and Precipitation in Inconel 718

In this study, the effect of the surface state on the behaviour of Inconel 718 alloy exposed to 640 ∘ C and 700 ∘ C environments for times varying between one and one hundred hours was investigated. In particular, the focus was set on the evolution of oxidation and precipitation phenomena during thermal exposure. Three surface states were considered: two generated through shot peening treatments featuring different coverage levels, while the third condition is a non-peened one. Shot peening treatments modify the surface condition and introduce higher residual stresses and microhardness values than in the non-treated condition. The morphology of the oxides appears to be different depending on the condition observed. Regarding the kinetics, over time the oxidation process follows a parabolic trend and appears to be influenced by the surface state; in particular, severe shot peening treatment is characterized by the highest intensity of the phenomenon. However, the order of magnitude of the weight gains measured suggests that the observed variations can be neglected, and that the positive effect of shot peening can be exploited without introducing oxidation problems. From the point of view of the microstructural evolution, an increase in the coarsening kinetics of γ ” phase was observed in the shot peened layer

Measures for the assessment of stressful life events in the Spanish adult population: A systematic review

Objetivo: Este estudio pretende identificar y analizar los instrumentos de evaluación de los eventos vitales estresantes creados/adaptados para su uso con población española adulta, publicados en la literatura nacional e internacional, con especial atención en sus propiedades psicométricas y en su asociación con medidas de problemas de salud. Métodos: Se llevó a cabo una revisión sistemática de la literatura de todos los instrumentos publicados a través de los buscadores MEDLINE; ProQuest Health y Medical Complete ProQuest Psychology Journals PsycARTICLES PsycINFO Psicodoc OpenSIGLE desde la fecha de inicio hasta el 31 de enero de 2016. Dos investigadores independientes evaluaron la elegibilidad de todos los artículos, extrajeron los datos y evaluaron sus propiedades psicométricas. Resultados: Se seleccionaron 12 instrumentos que cumplían los criterios de inclusión en el estudio. Las medidas presentaron una gran heterogeneidad. La mayoría no incluían información sobre sus propiedades psicométricas o necesitaban aportar más datos, ya que eran pocas los que evaluaban su estabilidad test-retest y/o su estructura interna. Los cuestionarios creados o adaptados por González de Rivera y Morena (1983), Sandín y Chorot (1987), Fernández y Mielgo (1992), Gracia y Herrero (2004) y Motrico et al. (2013) mostraron asociaciones significativas con variables de problemas de salud. Discusión: Se requieren más estudios sobre la asociación de los instrumentos con variables de problemas de salud mental y física, lo que facilitaría su aplicación clínica. Estos resultados tienen una gran utilidad a la hora de seleccionar un instrumento de evaluación de eventos vitales estresantes en el ámbito clínico y de investigación en España

Characterization of competing distortions in YFe2O4

We report the structural changes of three YFe2O4-δ (δ<0.1) specimens using high resolution synchrotron x-ray powder diffraction between 80 and 300 K. All samples adopt a rhombohedral cell at room temperature (space group R3m). This cell becomes unstable for the three samples on cooling, and the oxygen-poor specimen (δ∼0.1) shows a single transition at 240 K. The nearly stoichiometric (δ≤0.03) compounds exhibit two structural transitions with decreasing temperature at about 240 and 200 K. Each transition is revealed by an anomaly in the heat capacity measurements and a jump in the electric resistivity. Below 240 K, a strong splitting of some diffraction peaks is accompanied by the occurrence of superstructure peaks that follow the propagation vector k=(1/7,-2/7,9/7). The cell symmetry is then triclinic, and the structural transition is characterized by an expansion of the c axis coupled to a contraction of the other two lattice parameters. There are 49 nonequivalent sites for Fe atoms with a maximum charge disproportionation of ∼0.5e-. Upon cooling at 200 K, the previous superstructure peaks begin to vanish, and finally they are replaced by a new set of superstructure peaks following the propagation vector k=(1/4,1/2,1/4) with respect to the rhombohedral cell. The transition is also reflected in sudden changes in the lattice parameters that seem to smooth the changes observed in the previous transition. The new cell is also triclinic, and there are 48 nonequivalent Fe sites with a maximum charge disproportionation of ∼0.7e-. Both phases coexist in a wide temperature range because this second transition is not completed at 80 K. A symmetry mode analysis indicates a complicated pattern for the charge distribution in the Fe sublattice of both distorted structures but clearly discard any bimodal distribution of only two types of Fe cations. Therefore, the sharp jumps in the electric resistivity at the phase transitions are clearly correlated with two different structural changes. Finally, the oxygen stoichiometry seems to be a key factor in the stabilization of the different distorted structures.We are thankful for financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) (Projects No. MAT2012-38213-C02-1-2 and No. MAT2015-68760-C2-1-2, cofunded by the European Regional Development Fund [ERDF] allocated by the European Union) and Diputacion General de Aragón (DGA, project E69).Peer Reviewe

Evaluating destinations' efforts to improve sustainability in tourism using the inter-temporal decomposition of a composite indicator

This work was supported by grants from the Ministry of Economy and Competitiveness [PID2019-104263RB-C41 and PGC2018-095786-B-IOO], from the European Regional Development Fund (FEDER) and from the Ministry of Economy, Knowledge, Business and University, of the Andalusian Government, within the framework of the FEDER Andalusia 2014-2020 operational program. Specific objective 1.2.3. «Promotion and generation of frontier knowledge and knowledge oriented to the challenges of society, development of emerging technologies») within the framework of the reference research project (UPO-1380624). FEDER co-financing percentage 80%. Funding for open access publishing: Universidad Pablo de Olavide/CBUA.UPO-1380624, PID2019-104263RB-C41 and PGC2018-095786-B-IOOSustainable tourism indicators are instruments for measuring tourism sustainability, widely used in the planning and decision-making processes. For this measurement, in recent decades composite indicators have been proposed that provide dynamic evaluations to assess the progress that each destination registers towards more sustainable situations. However, the measures proposed so far do not allow the evaluation of each destination's own effort or the effectiveness of the measures put in place, because the evaluation they provide depends on the decisions made when adding information (weighting, reference situations...). In this study, a dynamic measure of sustainable tourism is proposed, which, through the intertemporal decomposition of a global indicator with multiplicative aggregation, assesses the effort that each destination makes to improve its sustainability situation. The aggregation procedure is carried out in two stages. In the first one, a compensatory synthetic indicator is obtained for each aspect using a weighting scheme determined from information and dispersion criteria. In a second phase, the global composite indicator is obtained with a multiplicative aggregation, setting unique and common weights for all destinations through DEA models and using different benchmarks for each type of destination, in order to take into account their different starting situations.Departmento de Economía, Métodos Cuantitativos e Historia Económica, Universidad Pablo de Olavid