Desarrollo de membranas híbridas dieléctricas de tipo Nafión con óxidos de zirconio, hafnio y lantano

En el presente trabajo se realizó la síntesis de membranas híbridas tipo Nafion/(MxOy)n donde M=Zr, Hf o La y n=1wt%. Las membranas fueron preparadas mediante el proceso Sol-Gel. Tres nuevas membranas fueron obtenidas con espesores de 61, 67 y 300 μm respectivamente. Cada membrana fue caracterizada mediante espectroscopia infrarroja, análisis termogravimétrico y microscoía electrónica de barrido. Obteniendo que las membranas híbridas presentan mayor resistencia térmica que el polimero por si solo adquiriendo 40ºC más, lo que da como resultado una temperatura de trabajo de 120ºC, además en los espectros de infrarrojo se evidencia la presencia del efecto del material inorgánico sobre el incremento en el carácter autohumidificante de la membrana híbrida, finalmente la microscopía electrónica de barrido nos permite identificar la obtención de la membrana híbrida mediante las micrografías así como el espesor de las mismas

Collaborative lifelong learning and professional transfer. Case study: ECO European Project

This research reviews the formative model of the sMOOCs (social MOOC) characterized by the interaction and the implication of the participants who, relying on collective intelligence, look for the co-creation of knowledge in every educational action. The fieldwork focuses on the analysis of the “Step by Step” sMOOC of ECO Project (the second and third editions), that aims at the training of e-teachers and the transfer of learning to the professional field. The research methodology is mixed, with quantitative and qualitative techniques: it uses a semi-structured questionnaire, in order to compare possible bivariate correlations between the different variables; it conducts a content analysis of the fragments of messages written by the participants in the forums of the course. One of the most significant conclusions is the high degree of satisfaction of the participants with regard to the value of the course for their professional life. This form of transfer of the learning process leads to the proposal of a new modality for MOOCs, the tMOOC as “transferMOOC”

The relationship between perceived social support and psychological distress in carers of older relatives: A longitudinal cross-lagged analysis

BACKGROUND AND OBJECTIVES: Although a large body of research has examined the relationship between social support and psychological health of family carers of frail older people, the exact nature and direction of this relationship is not well understood with most research to date being cross-sectional. This longitudinal study explored the relationship between perceived social support and psychological distress in carers of older relatives. METHODS: We used data from two longitudinal cohorts which included a total of 332 family carers of frail older people. We used cross-lagged panel analysis to investigate the longitudinal association between perceived social support and carer psychological distress controlling for a number of covariates over time. RESULTS: Fully-adjusted Generalised Estimating Equations (GEE) and cross-lagged models indicated that higher social support was significantly associated with lower carer psychological distress over time (regression coefficient [B] = -0.178, standard error [SE] = 0.028), with levels of perceived social support exerting an effect on psychological distress rather than vice versa (β = 0.03, p = 0.32). LIMITATIONS: All observations were based on self-report data, and there may be other variables that may explain the results that we did not account for. DISCUSSION AND IMPLICATIONS: Our study finds that the directionality of the relationship appears to be from perceived social support to carer psychological distress suggesting that social support directly affects carer psychological health but not vice versa. This finding has important implications for the provision of social support interventions for carers of frail older people at risk of experiencing psychological distress

The mediating role of sense of coherence on mental health outcomes in carers of older dependent relatives: a longitudinal study

Background: Sense of coherence (SOC) is an important protective factor for carer well‐being but research to date remains cross‐sectional, focusing primarily on the direct effects of SOC on carers’ mental health. The study's aim was to investigate the mediating role of SOC in the longitudinal relationship between caregiver strain and carers’ psychological health, and its stability over time. / Methods: Prospective longitudinal study conducted in Jaén (Spain) with a probabilistic sample of 132 carers of older people, with data collected at baseline and at one‐year follow‐up. We measured SOC, caregiver strain, anxiety and depressive symptoms, and several care recipient characteristics and intensity of care provided. We used multiple linear regression modelling and the Sobel test to analyse mediation effects. / Results: SOC was significantly negatively longitudinally associated with both anxiety (β= ‐0.38, p= 0.001) and depressive symptoms (β= ‐0.28, p= 0.023), after controlling for several confounders. SOC mediated both the relationship between caregiver strain and anxiety and caregiver strain and depressive symptoms (Sobel test; p< 0.001 for anxiety and p< 0.001 for depressive symptoms). Differences between baseline and one‐year follow‐up SOC scores were not statistically significant (p= 0.617). / Conclusions: SOC appears to buffer the impact of caregiver strain on symptoms of depression and anxiety in informal carers of older people. Our data showed that SOC is an important psychological resource for carers that remained relatively stable under non‐experimental conditions over a period of one year in this sample. Findings suggest that interventions aimed at strengthening SOC may protect carer psychological well‐being

The parasporal crystals of Bacillus pumilus strain 15.1: a potential virulence factor?

Bacillus pumilus strain 15.1 was previously found to cause larval mortality in the Med-fly 27 Ceratitis capitata and was shown to produce crystals in association with the spore. As 28 parasporal crystals are well-known as invertebrate-active toxins in entomopathogenic 29 bacteria such as Bacillus thuringiensis (Cry and Cyt toxins) and Lysinibacillus sphaericus (Bin 30 and Cry toxins), the B. pumilus crystals were characterised. The crystals were composed of a 31 45 kDa protein that was identified as an oxalate decarboxylase by peptide mass 32 fingerprinting, N-terminal sequencing and by comparison with the genome sequence of strain 33 15.1. Synthesis of crystals by a plasmid-cured derivative of strain 15.1 (produced using a 34 novel curing strategy), demonstrated that the oxalate decarboxylase was encoded 35 chromosomally. Crystals spontaneously solubilized when kept at low temperatures and the 36 protein produced was resistant to trypsin treatment. The insoluble crystals produced by 37 B. pumilus 15.1 did not show significant toxicity when bioassayed against C. capitata larvae, 38 but once the OxdD protein was solubilized, an increase of toxicity was observed. We also 39 demonstrate that the OxdD present in the crystals has oxalate decarboxylate activity as the 40 formation of formate was detected, which suggests a possible mechanism for B. pumilus 15.1 41 activity. To our knowledge, the characterization of the B. pumilus crystals as oxalate 42 decarboxylase is the first report of the natural production of parasporal inclusions of an 43 enzyme

Modelling the Interaction Levels in HCI Using an Intelligent Hybrid System with Interactive Agents: A Case Study of an Interactive Museum Exhibition Module in Mexico

Technology has become a necessity in our everyday lives and essential for completing activities we typically take for granted; technologies can assist us by completing set tasks or achieving desired goals with optimal affect and in the most efficient way, thereby improving our interactive experiences. This paper presents research that explores the representation of user interaction levels using an intelligent hybrid system approach with agents. We evaluate interaction levels of Human-Computer Interaction (HCI) with the aim of enhancing user experiences. We consider the description of interaction levels using an intelligent hybrid system to provide a decision-making system to an agent that evaluates interaction levels when using interactive modules of a museum exhibition. The agents represent a high-level abstraction of the system, where communication takes place between the user, the exhibition and the environment. In this paper, we provide a means to measure the interaction levels and natural behaviour of users, based on museum user-exhibition interaction. We consider that, by analysing user interaction in a museum, we can help to design better ways to interact with exhibition modules according to the properties and behaviour of the users. An interaction-evaluator agent is proposed to achieve the most suitable representation of the interaction levels with the aim of improving user interactions to offer the most appropriate directions, services, content and information, thereby improving the quality of interaction experienced between the user-agent and exhibition-agent

Heavy metal anomalies in lagoon sediments related to intensive agriculture in Altata-Ensenada del Pabellón coastal system

Abstract Heavy metal concentrations were examined in surface sediments from 79 sites within the Altata-Ensenada del Pabello Ân lagoon system. Data were normalized to separate natural from anthropogenic factors using aluminum and lithium as conservative elements and following two different discriminating criteria. For the normalization process, the natural metal concentrations were assumed to vary consistently with aluminum and lithium, unless the metal contents were of human origin. Strong linear correlations ( P &lt; .001) were observed between the conservative elements and the metals measured. According to Szefer&apos;s normalizing criteria, about 90% of the polluted sites, for at least one metal, occurred near agricultural discharge drains. In accordance with the Mu Èller [Umschau 79 (1979) 778.] scale, this lagoon system is subject to pollutant effects only with regard to Pb (moderately to strongly polluted). It was concluded that either Al and Li could be useful to normalize granulometric variability in heavy metal studies of these lagoon sediments, and that Summers&apos; normalization criterion proved more rigorous than Szefer&apos;s for these types of sediments.