Embedded Sensors For The Monitoring Of Durability

Embedded Sensors For The Monitoring Of Durabilit

Recombination processes in unintentionally doped GaTe single crystals

Emission spectra of GaTe single crystals in the range of 1.90–1.38 eV have been analyzed at different temperatures and excitation intensities by photoluminescence, photoluminescence excitation, and selective photoluminescence. A decrease in band gap energy with an increase in temperature was obtained from the redshift of the free exciton recombination peak. The energy of longitudinal optical phonons was found to be 14±1 meV. A value of 1.796±0.001 eV for the band gap at 10 K was determined, and the bound exciton energy was found to be 18±0.3 meV. The activation energy of the thermal quenching of the main recombination peaks and of the ones relating to the ionization energy of impurities and defects was analyzed. The results obtained show the existence of two acceptor levels with ionization energies of 110±5 and 150±5 meV, respectively, and one donor level with an ionization energy of 75±5 meV. The study of chemical composition by inductively coupled plasma-optical emission spectroscopy and x-ray energy dispersion spectroscopy shows the existence of Na, Li, and Si. Sodium and lithium impurities could be associated with acceptor levels at gallium substitutional sites, and silicon ones with a donor level at Ga sites, whose vacancies can also be involved in these electronic [email protected] ; [email protected]

El uso de personajes famosos en las campañas de screening de cáncer de colon

En esta investigación estudiamos la efectividad de la campaña de comunicación sobre la concienciación y prevención del cáncer de colon en España, y los personajes famosos utilizados, con el fin de analizar la idoneidad de su elección. En un experimento con una población mayor de 50 años, encontramos que la imagen de los personajes famosos utilizados no es adecuada. Además el grado de concienciación de la enfermedad no varía ante diferentes estímulos publicitarios. Los resultados de esta investigación deben ayudar a plantear una campaña de comunicación que incremente la tasa de respuesta en el cribado del cáncer de colon.In this research we analyze the effectiveness of the mass media communication campaign on awareness and prevention of colorectal cancer in Spain, also we analyze use and adequacy of celebrities in this campaigns. In an experiment with a population over 50 years, we find that image of celebrities is not such as good as expected. Furthermore, the degree of awareness of the disease don't change to the different advertising. Results from this research, must help us to carry out mass media campaigns in order to increase the response rate in screening for colon cancer

Fluorescence enhancement of fungicide thiabendazole by van der Waals interaction with transition metal dichalcogenide nanosheets for highly specific sensors

Many molecules quench their fluorescence upon adsorption on surfaces. Herein we show that the interaction of thiabendazole, a widespread used fungicide of the benzimidazole family, with nanosheets of transition metal dichalcogenides, particularly of WS2, leads to a significant increase, more than a factor of 5, of the fluorescence yield. This surprising effect is rationalized by DFT calculations and found to be related to the inhibition of the intramolecular rotation between the benzimidazole and thiazole groups due to a bonding rigidization upon interaction with the MoS2 surface. This non-covalent adsorption leads to a redistribution of the molecular LUMO that blocks the non-radiative energy dissipation channel. This unusual behaviour does not operate either for other molecules of the same benzimidazole family or for other 2D materials (graphene or graphene oxide). Moreover, we found that a linear dependence of the emission with the concentration of thiabendazole in solution, which combined with the specificity of the process, allows the development of a highly sensitive and selective method towards thiabendazole determination that can be applied to real river water samples. An excellent detection limit of 2.7 nM, comparable to the best performing reported methods, is obtained with very good accuracy (Er ≤ 6.1%) and reproducibility (RSD ≤ 4.1%) in the concentration range assayedThe authors acknowledge financial support from the Spanish MINECO (MAT2017-85089-C2-1-R, MAT2017-85089-C2-2-R) and the EU via the ERC-Synergy Program (grant ERC-2013-SYG-610256 NANOCOSMOS) and Horizon 2020 Research and Innovation Program (Graphene Flagship-core2 – 785219) and the Comunidad Autónoma de Madrid (P2018/NMT-4349, TRANSNANOAVANSENS-CM and P2018/NMT-4367 FOTOART). J. I. M. acknowledges the support by the “Ramón y Cajal” Program of MINECO (grant RYC-2015-17730

Application of a self-learning methodology for the enhancement of the oral communication student outcome in International Business studies

Effective oral communication is one of the most demanded student outcomes in the labour market, especially for degree students on International Business. Although this outcome is usually evaluated in several subjects along the curriculum, it is barely worked neither inside nor outside the classroom, mainly due to lack of time and to unavailability of proper learning methodologies. The PIMECOE project, an innovation and educational improvement project on this matter, has developed a self-learning methodology on the Effective Oral Communication student outcome, in which auto-diagnosis tests, selflearning tools and peer assessments are conveniently combined to enhance the proficiency level of the students in an autonomous way. As part of this project, and after some previous successful pilot studies, we have run this methodology with International Bussiness' students within the "Learning instruments and techniques" subject during the first semester of the 2018/2019 academic year at the Universitat de València. After carrying out a quantitative analysis of the results, we have found generalised improvements on the proficiency level of the oral communication outcome of the participant students. Satisfaction surveys suggest that the application of this methodology has really helped the student to become conscious of unrealised weaknesses and therefore to boost their oral skills

Understanding the influence of filler type and asphalt binder content on the moisture and fatigue resistance of asphalt mortars

An adequate moisture resistance is a key element to guarantee the durability of asphalt materials. This paper identifies the influence of filler typology and bitumen content on the mechanical response of asphalt mortars before and after water action. Two fillers were evaluated: Portland cement and Calcium carbonate, along with different contents of a penetration bitumen (B35/50). Stiffness, ductility, and fatigue were evaluated through a new protocol for asphalt mortar samples using a 3-point-bending test on DMA (Dynamic Mechanical Analyzer). The use of Portland cement presents higher stiffness, lower ductility, and improved fatigue and water resistance compared to Calcium carbonate. It is also possible to optimize bitumen content based on fatigue results. Content beyond the optimal reduce variations after water action but compromise fatigue resistance. Lower content leads to a poorer performance in both terms. This methodology enables asphalt mortar characterisation as a tool to optimise the design of asphalt materials.La influencia del tipo de polvo mineral y contenido de ligante bituminoso en la resistencia a la humedad y fatiga de morteros bituminosos. La resistencia al agua es clave para garantizar la durabilidad de los materiales asfálticos. Este estudio identifica la influencia del polvo mineral y contenido de betún en la respuesta mecánica de morteros bituminosos antes y después de la humedad. Se evaluaron dos tipos de filler: cemento Portland y carbonato cálcico (filler calizo), junto con distintos contenidos de betún (B35/50). Rigidez, ductilidad y fatiga fueron evaluados mediante un nuevo ensayo de fatiga a tres puntos para morteros empleando DMA (Dynamic Mechanical Analyzer). El cemento presenta más rigidez, menos ductilidad y mayor resistencia al agua y fatiga que el filler calizo. Los resultados de fatiga permiten además optimizar el contenido de betún. Contenidos por encima del óptimo reducen variaciones tras la humedad pero comprometen la resistencia a fatiga. Contenidos menores conllevan un peor comportamiento en ambos términos. Esta metodología permite usar la caracterización de morteros bituminosos para optimizar el diseño de materiales asfálticos

Unveiling the collaborative effect at the cucurbit[8]urilMoS2 hybrid interface for electrochemical melatonin determination

Host-guest interactions are of paramount importance in supramolecular chemistry and in a wide range of applications. Particularly well known is the ability of cucurbit[n]urils (CB[n]) to selectively host small molecules. We show that the charge transfer and complexation capabilities of CB[n] are retained on the surface of 2D transition metal dichalcogenides (TMDs), allowing the development of efficient electrochemical sensing platforms. We unveil the mechanisms of host-guest recognition between the MoS2- CB[8] hybrid interface and melatonin (MLT), an important molecular regulator of vital constants in vertebrates. We find that CB[8] on MoS2 organizes the receptor portals perpendicularly to the surface, facilitating MLT complexation. This advantageous adsorption geometry is specific to TMDs and favours MLT electro-oxidation, as opposed to other 2D platforms like graphene, where one receptor portal is closed. This study rationalises the cooperative interaction in 2D hybrid systems to improve the efficiency and selectivity of electrochemical sensing platform

Standard tests for the characterization of roofing slate pathologies

Las patologías que se originan en pizarra para cubiertas son debidas fundamentalmente a la presencia de materiales alterables (sulfuros de hierro, carbonatos y materia orgánica). Estos minerales pueden llegar a alterarse por efecto de los agentes medioambientales, una vez que la pizarra es puesta en obra. Las patologías están principalmente asociadas a procesos de oxidación y yesificación de las citadas fases minerales. En este trabajo se determinan las patologías potenciales de varias pizarras para cubiertas españolas, utilizando los ensayos definidos en las normas UNE-EN 12326:2005, 14147:2004 y 11597:2007.The pathologies formed in slate roofs are mainly due to the presence of potentially unstable minerals (iron sulfides, carbonates and organic matter). These minerals may become altered by the effect of environmental agents, once the slate roof is finished. The pathologies are mainly associated with oxidation and gypsification processes of the cited mineral phases. In this work, the potential pathologies of several Spanish roofing slates are identified, using the tests defined in the European Norms EN 12326:2005, 14147:2004 and 11597:2007.El presente trabajo se ha desarrollado en el marco del proyecto PERDURABLE: Durabilidad de materiales de piedra natural. Análisis y prevención de patologías. MICINN-09-CIT-380000-2009-25, financiado por el Ministerio de Ciencia e InnovaciónS

Actividad antimicrobiana de germicidas halogenados frente a aislamientos hospitalarios

Antiseptics and disinfectants are extensively used in hospitals and health care settings for a variety of topical and hard-surface applications. In particular, they are essential part of infection control practices and in the prevention of nosocomial infections. Despite this, few is known about the mode of action of these biocides with respect to antibiotics. In general, the antimicrobial activity can be influenced by many factors such as formulation effects, presence of organic matter, synergy, temperature, dilution and test method. The widespread use of antiseptics and disinfectant products has prompted some speculation on the development of microbial resistance, in particular cross-resistance to antibiotics. The aim of this study was to evaluate microbiological resistance to halogenated compounds by studying the behaviour of the grampositive and gramnegative clinical isolates against halogenated biocides usually applied, with and without organic substance and applying distilled water, potable water and water of 300 ppm hardness as dilution means. The results indicate that the hospital microorganisms show a higher resistance to the biocides than the strain Staphylococcus aureus ATCC 6538, although the effective concentration in clean conditions was lesser than the recommended ones, for all the dilution means. In presence of organic matter the antimicrobial activity was reduced in accordance with the bactericidal concentration of each microorganisrn, due to the oxidant action of these disinfectantsLos antisépticos y desinfectantes se emplean en hospitales para una gran variedad de aplicaciones, tanto tópicas como sobre superficies. Estos compuestos son esenciales en el control y la prevención de las infecciones nosocomiales. A pesar de esto, se conoce bastante menos acerca del modo de acción de estos biocidas que de los antibióticos habitualmente empleados en terapéutica. La actividad antimicrobiana puede ser influenciada por muchos factores tales como la formulación, la presencia de materia orgánica, efectos de sinergia, temperatura, dilución e incluso del método de ensayo. El uso tan difundido de productos desinfectantes y antisépticos ha llevado a algunas especulaciones sobre el desarrollo de resistencia microbiana, y particularmente, resistencia cruzada con antibióticos. Con el propósito de estudiar la resistencia microbiana a germicidas halogenados de uso corriente en ,centros asistenciales, se evaluó el comportamiento de aislamientos hospitalarios tanto gram negativos como gram positivos frente a soluciones de hipoclorito de sodio, iodopovidona y tintura de iodo en presencia y ausencia de sustancias interferentes tales como materia orgánica y cationes. Los multados obtenidos indican que los microorganismos hospitalarios presentan mayor resistencia a los bioddas analizados con respecto al microorganismo de ref- erencia Staphylococcus aureus ATCC 6538. Sin embargo, en condiciones limpias este grupe de biocidas posee una alta eficacia, aún muy por debajo de las concentraciones de uso recomendadas, para todos los medios de dilución estudiados. Con la presencia de materia orgánica la actividad germicida disminuyó en todos los casos en relación directamente proporcional a la concentración, debido a la naturaleza predominantemente oxidante de estos compuestos