Substrate influence on the ferroelectric properties of PTCa thin films

[ES] Se han estudiado las propiedades ferroeléctricas de láminas delgadas de titanato de plomo modificado con calcio (Pb0.76Ca0.24)TiO3 (PTCa) preparadas vía sol gel mediante cristalizaciones sucesivas sobre tres tipos de substratos: (A) Pt / Ti / SiO2 / Si (100), (B) Ti / Pt / Ti / SiO2 / Si(100) y (C) Pt / TiO2 / SiO2 /Si (100). Los resultados de la caracterización ferroeléctrica muestran valores del coeficiente piroeléctrico espontáneo entorno a » 5 .10-9 C cm-2 K-1. La baja conmutabilidad de las laminas facilita la estabilización del valor del coeficiente piroeléctrico en el tiempo. Un tratamiento térmico posterior de recocido a 650ºC 1 hora produce cambios en las propiedades ferro-piezoeléctricas que se pueden asociar con modificaciones de la textura en las láminas.[EN] The ferroelectric properties of calcium modified lead titanate (Pb0.76Ca0.24)TiO3 (PTCa) thin films prepared by a sol - gel method with successive crystallisations on three different substrates (A) Pt / Ti / SiO2 / Si (100), (B) Ti / Pt / Ti / SiO2 / Si(100) y (C) Pt / TiO2 / SiO2 /Si (100), have been studied. The results of the ferroelectric characterisation show values of the spontaneous pyroelectric coefficient close to » 5 .10-9 C cm-2 K-1. The low switching properties favour the stabilisation in time of the pyroelectric coefficient value. Alatter annealing thermal treatment (650ºC 1h) produces changes in the ferro - piezoelectric properties that can be related with changes in the texture of the films.Este trabajo ha sido realizado mediante la financiación recibida de los proyectos MAT98 - 1068 (CICYT) y BRPR - CT98 - 0777 (BRITE EURAM de la U.E.).Peer reviewe

Phylogenetic relationships of Chanidae (Teleostei: Gonorynchiformes) as impacted by Dastilbe moraesi, from the Sanfranciscana basin, Early Cretaceous of Brazil

Fossil gonorynchiform fishes range from the Lower Cretaceous to the early Miocene, and are represented by a few dozen living species. The order is currently divided into two major clades: Gonorynchoidei, which includes the families Gonorynchidae and Kneriidae, and Chanoidei, encompassing a single family, Chanidae, with a single recent species, the Indo-Pacific Chanos chanos, and several fossil taxa. Chanidae includes some poorly known taxa, such as Dastilbe moraesi, described from the Aptian (Lower Cretaceous) of the Areado Formation, Sanfranciscana basin, Brazil. This species is currently considered to be a junior synonym of the type species of its genus, Dastilbe crandalli, from Santana Formation, Aptian, northeastern Brazil. The analysis of abundant D. moraesi specimens revealed several new morphological features, many of which had previously been misinterpreted. Dastilbe moraesi was incorporated into a gonorynchiform character matrix as revised and modified for the Chanidae. We obtained a single most parsimonious tree in which D. moraesi is distinct and phylogenetically apart from D. crandalli. According our analysis, D. moraesi forms a sister pair with Chanos, a clade which is closely related to Tharrhias, all composing the tribe ChaniniGonorynchiformes fósseis ocorrem desde do Cretáceo inferior ao Mioceno inferior, e são representados por alguns representantes viventes. A ordem está dividida atualmente em dois clados principais: Gonorynchoidei, que inclui as famílias Gonorynchidae e Kneriidae, e Chanoidei, compreendendo uma única família, Chanidae, com uma única espécie vivente, Chanos chanos, do Indo-Pacífico, além de vários representantes fósseis. Chanidae inclui alguns táxons problemáticos, tais como Dastilbe moraesi, descrito do Aptiano (Cretáceo Inferior) da Formação Areado, bacia Sanfranciscana, Brasil. Esta espécie é atualmente considerada um sinônimo júnior da espécie-tipo de seu gênero, Dastilbe crandalli, da Formação Santana, Aptiano do nordeste do Brasil. A análise de abundante material de D. moraesi revelou várias novas características anatômicas, muitas das quais haviam sido previamente mal interpretadas. Dastilbe moraesi foi incorporado em uma matriz revisada de caracteres da família Chanidae. Nós obtivemos uma única árvore mais parcimoniosa na qual D. moraesi é distinto e filogeneticamente distante de D. crandalli. De acordo com nossa análise, D. moraesi é o grupo-irmão de Chanos, um clado intimamente relacionado a Tharrhias, com todos compondo a tribo ChaniniThis study was supported by CNPq (process # 401818/2010-1) and project CGL2013-42643P, Ministerio de Ciencia e Innovación de Españ

Digital skills, ICTs and students’ needs: a case study in social work degree, University of Zaragoza (Aragón-Spain)

Technological innovations are related to information and communication technologies (ICTs), which in turn have become a fundamental pillar in the field of education. Social work professionals require new approaches to take on the new type of work demanded by the digital society, specializing in research into the innovation of these new forms of action through technology. This article analyses whether university training is in tune with the new skills and abilities required for professional interventions in the twenty-first century. A total of 288 surveys were carried out on 309 students. Each survey consisted of 25 questions on the five digital skills areas. The results indicate that training in digital skills must gain space in university training plans, just as the pandemic became a starting point for the massive use of ICTs. The conclusions point to the importance of improving training in digital competences and skills for future generations of social workers, who, although they are digital natives, will need to know how to use ICTs in their social work

Suicide care from the nursing perspective: a meta‐synthesis of qualitative studies

Aims: to explore nurses' experiences of suicide care and to identify and synthesize the most suitable interventions for the care of people with suicidal behaviour from a nursing perspective. Design: qualitative meta-synthesis. Data sources: comprehensive search of five electronic databases for qualitative studies published between January 2015 and June 2019. Review methods: the PRISMA statement was used for reporting the different phases of the literature search and the Critical Appraisal Skills Programme (CASP) qualitative research checklist was used as an appraisal framework. Data synthesis was conducted using Sandelowski and Barroso's method. Results: seventeen articles met the inclusion criteria. The data analysis revealed 13 subcategories from which four main categories emerged: 'Understanding suicidal behaviour as a consequence of suffering', 'Nurses' personal distress in suicide care', 'The presence of the nurse as the axis of suicide care' and, 'Improving nurses' relational competences for a better therapeutic environment'. Conclusion: further training of nurses on the therapeutic relationship, particularly in non-mental health care work settings, and monitoring of the emotional impact on nurses in relation to suicide is required to promote more effective prevention and care. Impact: this review provides new insights on how suicide is interpreted, the associated emotions, the way suicide is approached and proposals for improving clinical practice from the point of view of nurses. The results demonstrate that the nurse-patient relationship, ongoing assessment, and the promotion of a sense of security and hope are critical in nursing care for patients who exhibit suicidal behaviour. Consequently, to promote an effective nursing care of suicide, nurses should be provided with further training on the therapeutic relationship. Thus, health institutions do not only provide the time and space to conduct an adequate therapeutic relationship, but also, through their managers, they should supervise and address the emotional impact that is generated in nurses caring for patients who exhibit suicidal behaviour

Aquella que ama el silencio : sobre la serpiente en los antiguos cultos egipcios

En un país como Egipto, donde los animales han sido objeto de culto, sorprende a menudo la figura de una cobra, presente en diversas manifestaciones de la vida diaria y religiosa desde época prehistórica. Y aunque sabemos que se ha perdido desde hace mucho tiempo la clave para comprender esta presencia y con ella, las de la religión egipcia la curiosidad nos hizo acercarnos a la figura de este animal, tan temido en la sociedad actual, buscando el por qué de su presencia en la vida egipcia

A New Chanidae (Ostariophysii: Gonorynchiformes) from the Cretaceous of Brazil with Affinities to Laurasian Gonorynchiforms from Spain

Based on specimens originally referred to as “Dastilbe minor”, a nomem-nudum, we describe a new genus of Chanidae †Nanaichthys longipinnus nov. gen. and sp. which exhibits several diagnostic characters such as the absence of orbitosphenoid and basisphenoid, anteriorly displaced quadrate-mandibular articulation, laterally expanded supraneurals, an acute angle between the preopercular limbs, expansion at the angle between the preopercular limbs, and a curved maxillary articular process. Its occurrence and supposed relationship within the Chanidae reinforce the influence of the Mediterranean Tethys over the Gondwanan main rift system prior to the Aptian/Albian highstands

Linseed oil gelled emulsion: a successful fat replacer in dry fermented sausages

Different levels of animal fat replacement by a high omega-3 content carrageenan gelled emulsion in dry fermented sausages were studied in order to improve their fatty acid composition. Percentages of fat replacement were 26.3% (SUB1), 32.8% (SUB2) and 39.5% (SUB3). α-linolenic acid (ALA) content increased up to 1.81, 2.19 and 2.39g/100g (SUB1, SUB2, and SUB3 products) as compared to the Control (0.35g/100g), implying an increment in polyunsaturated fatty acids (PUFA) supply (up to 10.3%) and reductions in omega-6/ omega-3 ratio (75, 82 and 84%, respectively). Peroxides and TBARs values were not affected (P>0.05) by the fat modification and a slight low formation of volatile aldehydes derived from lipid oxidation was detected. Fat replacement did not cause relevant modifications on the instrumental color properties and no sensory differences (P>0.05) were found between Control and SUB2 products (32.8%) for taste and juiciness, pointing out the viability of this formulation for human consumption

Cholesterol and stigmasterol within a sunflower oil matrix: Thermal degradation and oxysterols formation

The characteristics of the lipid matrix surrounding sterols exert a great influence in their thermal oxidation process. The objective of this work was to assess the oxidation susceptibility of equal amounts of cholesterol and stigmasterol within a sunflower oil lipid matrix (ratio 1:1:200) during heating (180 ºC, 0 to 180 min). Remaining percentage of sterols was determined and seven sterol oxidation products (SOPs) were analyzed for each type of sterol along the heating treatment. Evolution of the fatty acid profile and vitamin E content of the oil was also studied. Overall oxidation status of the model system was assessed by means of Peroxide Value (PV) and TBARS. PV remained constant from 30 min onwards and TBARS continued increasing along the whole heating treatment. Degradation of both cholesterol and stigmasterol fitted a first order curve (R2= 0.937 and 0.883, respectively), with very similar degradation constants (0.004 min-1 and 0.005 min-1, respectively). However, higher concentrations of oxidation products were found from cholesterol (79 μg/mg) than from stigmasterol (53 μg/mg) at the end of the heating treatment. Profile of individual oxidation products was similar for both sterols, except for the fact that no 25-hydroxystigmasterol was detected. 7α-hydroxy and 7-ketoderivatives were the most abundant SOPs at the end of the treatment. PUFA and vitamin E suffered a significant degradation along the process, which was correlated to sterols oxidation

A novel approach to monitor the oxidation process of different types of heated oils by using chemometric tools

The oxidative stability of seven oils with different fatty acid profiles was assessed. Oxidation at 0, 2 and 4 h at 180 °C was monitored by measuring the absorbance of thiobarbituric acid reactive substances (TBARS) along the absorption spectrum (300–600 nm), the volatile aldehydes (HS-SPME–GC–MS) and the fatty acid profile (FID-GC). TBARS absorption spectrum behavior depended on the lipid composition of heated oils. Higher absorbance increments during heating were noticed at 390 nm compared to 532 nm (from 2 to 21 fold higher depending on the oil), pointing to its better sensitivity to detect oxidation. Furthermore, a close relationship between ABS390, the loss of polyunsaturated fatty acids and their corresponding oxidation compounds (volatile aldehydes) was revealed by Principal Component Analysis. Multiparametric equations allowed predicting the formation of volatile aldehydes of heated oils by measuring only two parameters: TBARS390 during their heating, and the lipid profile in unheated oils (MUFA, ω-3 and ω-6). Results pointed out the interest of choosing ABS390 when the oxidative evolution of vegetable oils under heating is assessed by the TBARS test

Influencia de la concentración de oxígeno en el agua de riego en la producción de tomate de industria

Póster presentado al XXXVII Congreso Nacional de Riegos, celebrado en Don Benito del 4 al 6 de Junio de 2019 y organizada por la Asociación Española de Riegos y Drenajes y la Universidad de ExtremaduraObjetivo: Análisis de la influencia de la concentración de oxígeno disuelto en agua (ODA) de riego en la producción y en la calidad del fruto en plantaciones de tomate de industria inyectado mediante dispositivos venturi en redes de riego por goteo