A sustainable evaluation of drilling parameters for PEEK-GF30

Producción CientíficaThis paper presents a study of hole quality and energy consumption in the process of drilling a thermoplastic polymeric material, polyether-ether-ketone, reinforced with 30% glass fibers (PEEK-GF30). PEEK-GF30’s capacity to be machined has focused on turning operations. Studies of drilling involving thermoplastic polymeric materials have considered materials with other types of matrices, or reinforcement. In this study, quantities such as maximum and mean surface roughness, delamination, maximum thrust force, maximum momentum, and energy required during the process were determined for three types of drill bits, and the most influential factors for each variable were identified using an ANOVA multifactor analysis. The highest quality and lowest energy consumption were achieved for a drill bit rotation speed of 7000 rpm and a feed rate of 400 mm/min with a tungsten carbide (WC) drill bit coated with titanium aluminum nitride (TiAlN). Although a WC drill bit with a diamond point reduces delamination, the roughness increases, thus, the choice of the drill bit type depends on the roughness allowed. A WC drill bit coated with TiAlN produces a good surface finish that can eliminate subsequent operations and requires less energy; thus, this type of drill bit is the most attractive of the types evaluated.Ministerio de Economía de España y Competitividad, (Proyecto DPI2011-27135)Escuela Técnica Superior de Ingenieros Industriales de la UNE (Project ICF03

Inventario de la vegetación y estudio de la interferencia biocida con los materiales pétreos del yacimiento del cerro de la plaza de armas de Puente Tablas (Jaén)

Las rocas pueden sufrir procesos de alteración de tres tipos: físicos, químicos y biológicos. La alteración biológica se debe a la influencia ejercida por los vegetales, superiores e inferiores, y por los animales. La vegetación puede producir alteraciones por varias causas. El artículo establece un Inventario de la vegetación y estudio de la interferencia biocida con los materiales pétreos del yacimiento del cerro de la plaza de armas de Puente Tablas (Jaén)

Indicators toMeasure Efficiency in Circular Economies

In this paper, a number of indicators are shown to measure economic efficiency in terms of circular economy (CE). The European Union affirms the need for a comprehensive model of indicators relating to CE in order to meet the needs of all participants (individual companies and industry, society, and the nation), to be based on three perspectives: environmental impact, economic benefit, and resource scarcity. Therefore, the objective of this work is to define these indicators and establish models for measuring the efficiency of processes and products of CE (through Data Envelopment Analysis, (DEA)) in its different manifestations. The models will be useful for both organizations and external users in relation to CE in order to facilitate the search for indicators for all users. Following the bibliographic review of official reports and different high impact works, our results demonstrate the ability to obtain information concerning the main indicators of CE and how the efficiency of CE models has been measured through the most frequently used inputs and outputs

Capital público, actividad económica privada y efectos desbordamiento: Un análisis por Comunidades Autónomas de los sectores Industria y Construcción en España

En este trabajo se presenta una valoración del impacto de la infraestructura pública sobre la actividad privada española en los sectores de Industria y Construcción por CC.AA. para el período 1980-1993. El enfoque utilizado consiste en la estimación de una función de costes transcendental logarítmica, obteniendo resultados, entre otros, de la productividad del capital público y privado a corto y a largo plazo. Además, a diferencia de otros estudios, se considera la posible existencia de efectos desbordamiento del capital público entre regiones. Classification-JEL : D21, H54, O47. Infraestructura pública, efectos desbordamiento, función de costes, productividad.

Influence of the sociocultural perspective on the sensory perception of wine consumers in Mexico and Spain

The increasing globalization of companies and markets, including the wine market, makes this study important as a cultural comparison between the sensory perception of wine in Mexico and Spain. Eighty consumers were selected with different consumption habits, and hedonic (Acceptance and Simple Preference) and descriptive (Word Association Task and the Check-All-That-Apply (CATA) method) sensory tests were performed. The results revealed that there were differences in the conceptualization of wine in the Word Association Task. Both populations preferred wines of Spanish origin over those of Mexican origin, especially in the case of red wine.Postprint (published version

Evolution of metakaolin thermal and chemical activation from natural kaolin

In the present paper, we study the combined effect of thermal activation (600 °C/2 h and 750 °C/2 h) and chemical activation with 1% ZnO on the reactivity of metakaolinite (MK) obtained from natural kaolin. The phases are identified by chemical (ICP/MS), mineralogical (XRD), and morphological (SEM/EDX) characterization of all products, as well as the evolution and stability over time of the hydrated phases generated during the reaction, to determine their use as pozzolan in the manufacture of cements. The stability analysis for the kaolin/lime system activated chemically and thermally at 600 °C/2 h shows that the C-S-H gels are thermodynamically stable after one day of reaction, evolving the system to the stability field of stratlingite for the other analyzed times. At 750 °C/2 h, the thermodynamically stable reaction phases are C-S-H gels. Calcination at 600 °C/2 h and the addition of 1% ZnO are the optimal conditions for thermal and chemical activation, to improve the pozzolanic reaction and promote the replacing part of the cement for developing secondary reaction products

Down-regulation of a pectin acetylesterase gene modifies strawberry fruit cell wall pectin stracture and increases fruit firmness

Antisense-mediated down-regulation of several fruit-specific genes has previously demonstrated how the cell wall disassembly in strawberry fruit is mediated by a series of enzymes that act sequentially (Posé et al. 2011). An interesting example, the silencing of the polygalacturonase gene FaPG1, was also related with a significant increase of the post-harvest strawberry fruit firmness (Posé et al. 2013). Our research group has isolated a pectin acetylesterase gene, FaPAE1, which expression is enhanced during strawberry ripening. The main goal of this work was to elucidate the role of the degree of acetylation in cell wall integrity and fruit firmness through the antisense-mediated down-regulation of FaPAE1 in strawberry plants. Several transgenics lines were generated and 5 of them produced fruits 5-15% firmer than controls. Cell wall from ripe fruits was isolated from two independent transgenic lines and a control line, and sequentially extracted with different solvents (PAW, H2O, CDTA, Na2CO3). Modifications in fraction yield, its sugar composition and the degree of acetylation in each fraction were determined. Higher amounts of CDTA and Na2CO3 fractions were obtained in transgenic fruits, suggesting a decreased pectin solubilization as results of FaPAE1 silencing. Accordingly, the degree of acetylation of the Na2CO3-soluble pectins was greater in the transgenic lines than the control, but the opposite result was found in pectins from the CDTA fraction. These results suggest that PAE is preferentially active in pectis that are tightly bound to the cellulose-hemicellulose network and its activity could reduce the complexity of the cell wall structure, allowing that other hydrolytic enzymes could access the pectin chains. Thus, the increased fruit firmness observed in the transgenic FaPAE1 lines could be attributed to the direct effect of the silencing of the PAE enzyme and also to the indirect effect that the increase of the degree of acetylation of pectins has on the activity of other enzymes involved in the cell wall degradation. * Posé et al. (2011). Genes, Genomes and Genomics, 5 (Special Issue 1):40-48 * Posé et al. (2013). Plant Physiology, 150: 1022-1032 We acknowledge support from the Spanish Ministry of Economy and competitivity and Feder EU Funds (grant reference AGL2011-24814), FPI fellowships support for SP (BES-2006-13626) and CP (BES-2009027985), and grant "Ramón y Cajal" support for AJMA (RYC-2011-08839).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Training with videogames for improving sustained attention in children with a high risk of learning disorders

Most studies examine the effects of videogames on the cognitive abilities of young and adult players in experimental situations or for rehabilitation purposes. The aim of the present study is to evaluate the use of computerized commercial games for training sustained attention in primary school children at a high risk of learning disorders. A continuous performance task was used to assess sustained attention in a pre- and post-intervention classical paradigm. The training was organized in groups according to the children's age and grade and planned in 30-minute sessions twice weekly for 12 weeks. The Student's t-test was statistically significant for the mean reaction times, showing lower response times after training. It was demonstrated that more than twelve videogame sessions are needed to decrease the reaction time (mean RT) as significant relationship with sustained attention. Statistically significant results by age and grade were achieved before training, while at the end of the intervention only age had the same significance in the three age groups in relation to the mean RT. The results of the study suggest the need to continue exploring videogames in children at high risk of learning disorders.La majoria dels estudis examinen els efectes dels videojocs sobre les capacitats cognitives dels joves jugadors i adults en situacions experimentals o amb finalitats de rehabilitació. L'objectiu de l'estudi és avaluar l'ús de jocs comercials informatitzats per a la formació d'atenció sostinguda en nens amb un alt risc de trastorns de l'aprenentatge en una mostra de 32 escolars de primària. Es va utilitzar una tasca d'execució contínua per avaluar l'atenció sostinguda en un paradigma clàssic pre- i postintervenció. La formació es va organitzar en grups d'edat i grau i es va planificar en sessions bisetmanals de 30 minuts durant 12 setmanes. La prova t de Student va ser estadísticament significativa per a la mitjana dels temps de reacció després de la formació. Es va demostrar que es necessiten més de 12 sessions de videojocs per reduir el temps mitjà de reacció com a indicador de l'atenció sostinguda. Es van obtenir resultats estadísticament significatius per edat i nota abans de la formació, mentre que al final de la intervenció només l'edat va guanyar la mateixa importància. Els resultats de l'estudi suggereixen la necessitat de continuar explorant l'ús de videojocs en nens amb un alt risc de trastorns de l'aprenentatge.La mayoría de los estudios examinan los efectos de los videojuegos sobre las habilidades cognitivas de jugadores jóvenes y adultos en situaciones experimentales o con fines de rehabilitación. El objetivo del estudio es evaluar el empleo de juegos comerciales informatizados para el entrenamiento de la atención sostenida en niños con alto riesgo de trastornos del aprendizaje en una muestra de 32 escolares de primaria. Se utilizó una tarea de ejecución continua para evaluar la atención sostenida en un paradigma clásico pre- y postintervención. El entrenamiento se organizó en grupos según la edad y el grado y se planificó en sesiones bisemanales de 30 minutos durante 12 semanas. La prueba t de Student fue estadísticamente significativa para la media de los tiempos de reacción después del entrenamiento. Se demostró que se necesitan más de 12 sesiones de videojuegos para reducir el tiempo promedio de reacción como indicador de la atención sostenida. Se obtuvieron resultados estadísticamente significativos para la edad y el grado antes del entrenamiento, mientras que, al concluir la intervención, solo la edad obtuvo igual significación. Los resultados del estudio sugieren la necesidad de continuar explorando el uso de videojuegos en niños con alto riesgo de trastornos del aprendizaje

ELEMENTOS DE LOS MODELOS DETERMINANTES DEL CLIMA ORGANIZACIONAL

From importing the organizational climate has with in organizations, since it is the perception of human capital in relationtotheenvironment in which it is developed and share dwithco workers, is considered as a factor that reflects the facilities or obstaclesfacedby the worker to work in the employment context, for this reasonis considered extremely important and essential to have instrumentsto determine thelevel of organization alclimateperceivedby workers. There for edocumentaryre search, is ananalysis of the various existing measurement instruments in the literature regarding the organizational climate in differentareas (private companies, educational organizations, government agencies, health care organizations, and others) purpose. The importance of the analysis of the seinstruments is that they are indispensable to assessthe climate with in organization stool, there by generating strategies to directthea ctions, in orderto balance and achieve organizational behavior, group and individual positive. To measure the organizational climate has been identified in the literature to develop a largenumber of measuring instruments, amongwhichmay be mentione distheonepreparedby Mellado (2004), Chiang (2003), Brown and Leigh (1996) between other. They consider different dimensions of the work environment, such as individual responsibility, remuneration, risk and decisionmaking, support, tolerance, conflict, amongothers. The methodology consisted of literature review to identify various measurement instruments developed. Of which the definitions of organization alclimate addressed by the authors, measuring instruments, the oretical approaches, dimensions and values of validity and reliability in each were analyzed to determine if they are useful and feasible to apply to the Mexican contextd etermined by the investigat or according to the irinterests, stillarises at theend of the presentres earch findings and recommend ations for the selection and analysis instruments forme asuringorganizational climate, according to the type of organization, purposesassessment and identified organizational problems