Guía turística deportiva de Zahara de la Sierra (Cádiz, Andalucía)

Universidad de Sevilla. Grado en Turism

Preparación y caracterización de un material compuesto poli(uretano)/hidroxiapatita mediante separación de fases

Recientemente se han utilizado materiales porosos para la regeneración del tejido óseo, uno de los aspectos más importantes es contar con una morfología controlada la cual sirva como base y guía para el crecimiento del tejido. En este trabajo se han preparado poliuretanos y compositos poliuretano/hidroxiapatita por una separación de fase inducida térmicamente; por medio de la cual se pudieron producir materiales porosos con una morfología controlada y reproducible. La microestructura fue controlada por la variación en la concentración del polímero, temperatura de congelamiento, relación solvente/no solvente y co-solvente utilizado. Usando está técnica se pueden obtener materiales con un tamaño de poros desde unas cuantas micras hasta 200 mm. Debido a la porosidad interconectada y a la bioactividad que proporciona la hidroxiapatita pueden ser una alternativa para la regeneración del tejido óseo.Peer Reviewe

Effect of pH and nanoclay content on the morphology and physicochemicalproperties of soy protein/montmorillonite nanocomposite obtained byextrusion

The present work attempts to clarify the influence of montmorillonite nanoclay content and pH on the me-chanical properties of extruded soy protein nanocomposites. The mechanical behaviour is dominated by theformation of positive synergies between protein and nanoclay above a nanoclay concentration threshold.Moreover, the presence of nanoclay can improve water uptake. The pH also exerts a strong influence on me-chanical and water absorption properties, although montmorillonite tend to reduce this effect.Eventually, this study put forward the feasibility of using a combination of soy protein and montmorillonite toobtain potentially attractive biodegradable nanocomposite materials, processed by means of a simple and easilyscalable twin-screw extruder.Junta de Andalucía (project TEP-6134)Ministerio de Economía y Competitividad (CTQ2015-71164-P

Emulsifying properties of legume proteins at acidic conditions: Effect of protein concentration and ionic strength

Postprint de http://freepaper.me/PDF/?pdfURL=aHR0cHM6Ly9mcmVlcGFwZXIubWUvbi9qNTdpWjNMejV0OXhlNzYxS1diN09BL1BERi85ZS85ZWIyMzBmYWU2ZWI1ZDg2OGIyM2FjM2U4MDA3NGEyNy5wZGY=&doi=10.1016/j.lwt.2015.10.051This work is focused on emulsifying properties of pea, chickpea and lentil protein isolates at acidic conditions (pH 3), as affected by protein concentration and ionic strength. Emulsions characteristics and stability (droplet size distribution, flocculation, coalescence and creaming) were determined. The microstructure of selected emulsions was also studied. Results indicated that emulsifying properties (ability and stability) are dependent to protein concentration and highly sensitive to ionic strength. In our conditions, the best emulsifying properties are found around 1.5% of protein, and at less than 50 mM of NaCl. Clearly, ionic strength affects emulsions microstructure. Thus, this study indicated that pea, chickpea and lentil proteins would have great potential as emulsifiers in acidic food formulations.Universidad de BéjaiaUniversidad de SevillaMicroscopy Service (CITIUS-Universidad de Sevilla

Fitting Nonlinear Calibration Curves: No Models Perfect

The study of the calibration of a series of compounds of environmental concern (six perfluoroalkyl compounds (perfluorooctane sulfonic acid and five perfluoroalkyl carboxylic acids), three preservatives (methyl-, ethyl- and propylparabens) and the brominated flame retardant hexabromocyclododecane) by LC-MS/MS has been carries out, with a view to their simultaneous determination in samples of environmental interest. In some cases nonlinear calibration curves are obtained, but restricting the concentration range a linear model may be used to fit the data. Residual analysis has been performed in order to verify which models fit the data better, opting for a compromise decision given the apparent complexity of residuals plots. As Box states there are no perfect models (but models that work better than others)

Habilidades gerenciales y toma de decisiones en la gestión de la Municipalidad Provincial de Huaraz, 2015

El presente trabajo de investigación titulada Habilidades gerenciales y toma de decisiones en la gestión de la Municipalidad Provincial de Huaraz, 2015, tuvo como problema general, ¿Cuál es la relación entre las habilidades gerenciales y la toma de decisiones en la gestión de la Municipalidad Provincial de Huaraz, 2015? y como objetivo principal determinar la relación que existe entre las habilidades gerenciales y la toma de decisiones en la gestión de la Municipalidad Provincial de Huaraz, 2015. La muestra de estudio estuvo conformada por 157 trabajadores de la Municipalidad Provincial de Huaraz, 2015. Como instrumentos de diagnóstico se utilizaron dos cuestionarios tipo escala de Likert. La investigación se ha elaborado bajo los procedimientos metodológicos del enfoque cuantitativo, diseño de investigación no experimental, del tipo correlacional. Los datos obtenidos del instrumento aplicado fueron procesados mediante un software estadístico denominado SPSS versión 21 en los casos de las variables de habilidades gerenciales y toma de decisiones. En cuanto a los resultados podemos mencionar que sometidos los resultados de las encuestas a la prueba estadística de Rho de Spearman, se aprecia que sí existe relación significativa entre habilidades gerenciales y toma de decisiones, hallándose un valor calculado donde p = 0.000 a un nivel de significancia de 0.05 (bilateral), y un nivel de correlación de 0.701; lo cual indica que la correlación es positiva intensa

Rice Bran-Based Bioplastics: Effects of Biopolymer Fractions on Their Mechanical, Functional and Microstructural Properties

Rice bran is an underutilized by-product of rice production, containing proteins, lipids and carbohydrates (mainly starches). Proteins and starches have been previously used to produce rice bran-based bioplastics, providing a high-added-value by-product, while contributing to the development of biobased, biodegradable bioplastics. However, rice bran contains oil (18–22%), which can have a detrimental effect on bioplastic properties. Its extraction could be convenient, since rice bran oil is becoming increasingly attractive due to its variety of applications in the food, pharmacy and cosmetic industries. In this way, the aim of this work was to analyze the effect of the different components of rice bran on the final properties of the bioplastics. Rice bran refining was carried out by extracting the oil and fiber fractions, and the effects of these two procedures on the final properties were addressed with mechanical, functional and microstructural measures. Results revealed that defatted rice bran produced bioplastics with higher viscoelastic moduli and better tensile behavior while decreasing the water uptake capacity and the soluble matter loss of the samples. However, no significant improvements were observed for systems produced from fiber-free rice bran. The microstructures observed in the SEM micrographs matched the obtained results, supporting the conclusions drawn

Influence of the plasticizer on rice bran-based eco-friendly bioplastics obtained by injection moulding

The manufacture of eco-friendly bioplastic materials from renewable resources to replace petroleum-based plastics has attracted increasing attention. For many years, proteins, lipids and polysaccharides have been proposed as natural biopolymers sources to obtain biodegradable plastic materials. As by-product from the rice industry, rice bran, is an available and non-expensive resource of both proteins and starches, food groups that, properly processed, can be employed in the development of bioplastics. Plasticizers are essential for the manufacture of bioplastics and, when carbohydrate/protein mixtures are used, an adequate selection of plasticizers must be addressed. By these means, a material suitable for thermo-mechanical processing methods is obtained if starches are subjected to shear forces under high temperatures and water excess (gelatinisation). Moreover, additional polyol-based plasticizers, such as glycerol and sorbitol, allow obtaining reinforced products with improved elasticity when protein-based bioplastics are processed. The aim of the present study was to analyse the plasticizing effect of water combined with different proportions of glycerol or sorbitol, as well as their influence on the final bioplastic properties. Results indicate that higher water ratios produce stiffer bioplastics with improved viscoelastic moduli, maximum stress and Young´s modulus, while increasing the glycerol and sorbitol content leads to higher elasticities and water uptake capacities in general. Moreover, sorbitol seems to provide more suitable bioplastics with better tensile (up to 500% in Young´s modulus) and functional properties compared to glycerol.Ministerio de Ciencia e Innovación y FEDER RTI2018-097100-B-C2

Skills in end-of-degree project: Development and assessment

Desde la entrada de los nuevos títulos de Grado, se requiere la realización de Trabajos Fin de Grado (TFG) cuyo foco, según la especialización, puede tener un carácter teórico o práctico. En la experiencia presentada, los requisitos de la titulación exigen un trabajo eminentemente práctico por lo que los alumnos se encuentran una oportunidad inmejorable, no sólo de desarrollar las competencias propias de esta asignatura sino que también de poner en prácticas distintas competencias adquiridas a lo largo de su titulación. Este trabajo desarrolla una nueva metodología de trabajo, basada en la autonomía del estudiante y que, mediante un sistema de retroalimentación, permite la mejora continua.Since the entry into force of new degrees, end-of-degree projects, whose goal could be theoretical or practical, is required to obtain a degree qualification. In this work, degree rules compel to carry out a highly practical proposal. Furthermore, pupils have a great opportunity not only for developing degree skills but also for implementing different acquired skills for their degree studies. This study develops a new work methodology, based on student autonomy, in which the continuing improvement is achieved through a feed-back system