Integrated learning of production engineering software applications in a shipbuilding context

Acourse focused on the acquisition of integration competencies in ship production engineering, organized in collaboration with selected industry partners, is presented in this paper. The first part of the course is dedicated to Project Management: the students acquire skills in defining, using MS-PROJECT, the work breakdown structure (WBS), and the organization breakdown structure (OBS) in Engineering projects, through a series of examples of increasing complexity with the final one being the construction planning of a vessel. The second part of the course is dedicated to the use of a database manager, MS-ACCESS, in managing production related information.Aseries of increasing complexity examples is treated, the final one being the management of the piping database of a real vessel. This database consists of several thousand pipes, for which a production timing frame is defined connecting this part of the course with the first one. Finally, the third part of the course is devoted to working withFORAN,an Engineering Production application developed bySENERand widely used in the shipbuilding industry. With this application, the structural elements where all the outfittings will be located are defined through cooperative work by the students, working simultaneously in the same 3D model. In this paper, specific details about the learning process are given. Surveys have been posed to the students in order to get feedback from their experience as well as to assess their satisfaction with the learning process, compared to more traditional ones. Results from these surveys are discussed in the paper.

Descriptive study of production factors affecting performance traits in growing-finishing pgis in Spain.

The objective of this study was to build up a data set including productive performance and production factors data of growing-finishing (GF) pigs in Spain in order to perform a representative and reliable description of the traits of Spanish growing-finishing pig industry. Data from 764 batches from 452 farms belonging to nine companies (1,157,212 pigs) were collected between 2008 and 2010 through a survey including five parts: general, facilities, feeding, health status and performance. Most studied farms had only GF pigs on their facilities (94.7%), produced ‘industrial’ pigs (86.7%), had entire male and female (59.5%) and Pietrain-sired pigs (70.0%), housed between 13-20 pigs per pen (87.2%), had  50% of slatted floor (70%), single-space dry feeder (54.0%), nipple drinker (88.7%) and automatic ventilation systems (71.2%). A 75.0% of the farms used three feeding phases using mainly pelleted diets (91.0%), 61.3% performed three or more antibiotic treatments and 36.5% obtained water from the public supply. Continuous variables studied had the following average values: number of pigs placed per batch, 1,515 pigs; initial and final body weight, 19.0 and 108 kg; length of GF period, 136 days; culling rate, 1.4%; barn occupation, 99.7%; feed intake per pig and fattening cycle, 244 kg; daily gain, 0.657 kg; feed conversion ratio, 2.77 kg kg-1 and mortality rate, 4.3%. Data reflecting the practical situation of the Spanish growing and finishing pig production and it may contribute to develop new strategies in order to improve the productive and economic efficiency of GF pig units.

Molecular physiology of nickel and cobalt homeostasis in Rhizobium leguminosarum.

Transition metals such as Fe, Cu, Mn, Ni, or Co are essential nutrients, as they are constitutive elements of a significant fraction of cell proteins. Such metals are present in the active site of many enzymes, and also participate as structural elements in different proteins. From a chemical point of view, metals have a defined order of affinity for binding, designated as the Irving-Williams series (Irving and Williams, 1948) Mg2+ menor que Mn2+ menor que Fe2+ menor que Co2+ menor que Ni2+ menor que Cu2+mayor queZn2+ Since cells contain a high number of different proteins harbouring different metal ions, a simplistic model in which proteins are synthesized and metals imported into a ?cytoplasmic soup? cannot explain the final product that we find in the cell. Instead we need to envisage a complex model in which specific ligands are present in definite amounts to leave the right amounts of available metals and protein binding sites, so specific pairs can bind appropriately. A critical control on the amount of ligands and metal present is exerted through specific metal-responsive regulators able to induce the synthesis of the right amount of ligands (essentially metal binding proteins), import and efflux proteins. These systems are adapted to establish the metal-protein equilibria compatible with the formation of the right metalloprotein complexes. Understanding this complex network of interactions is central to the understanding of metal metabolism for the synthesis of metalloenzymes, a key topic in the Rhizobium-legume symbiosis. In the case of the Rhizobium leguminosarum bv viciae (Rlv) UPM791 -Pisum sativum symbiotic system, the concentration of nickel in the plant nutrient solution is a limiting factor for hydrogenase expression, and provision of high amounts of this element to the plant nutrient solution is required to ensure optimal levels of enzyme synthesis (Brito et al., 1994).

Physiological features of Schizosaccharomyces pombe of interest in the making of white wines

This work studies the physiology of Schizosaccharomyces pombe strain 938 in the production of white wine with high malic acid levels as the sole fermentative yeast, as well as in mixed and sequential fermentations with Saccharomyces cerevisiae Cru Blanc. The induction of controlled maloalcoholic fermentation through the use of Schizosaccharomyces spp. is now being viewed with much interest. The acetic, malic and pyruvic acid concentrations, relative density and pH of the musts were measured over the entire fermentation period. In all fermentations in which Schizo. pombe 938 was involved, nearly all the malic acid was consumed and moderate acetic concentrations produced. The urea content and alcohol level of these wines were notably lower than in those made with Sacch. cerevisiae Cru Blanc alone. The pyruvic acid concentration was significantly higher in Schizo. pombe fermentations. The sensorial properties of the different final wines varied widely.

Utilizing the Internet of Things to promote energy awareness and efficiency at discrete production processes: Practices and methodology

El actual contexto de fabricación, con incrementos en los precios de la energía, una creciente preocupación medioambiental y cambios continuos en los comportamientos de los consumidores, fomenta que los responsables prioricen la fabricación respetuosa con el medioambiente. El paradigma del Internet de las Cosas (IoT) promete incrementar la visibilidad y la atención prestada al consumo de energía gracias tanto a sensores como a medidores inteligentes en los niveles de máquina y de línea de producción. En consecuencia es posible y sencillo obtener datos de consumo de energía en tiempo real proveniente de los procesos de fabricación, pero además es posible analizarlos para incrementar su importancia en la toma de decisiones. Esta tesis pretende investigar cómo utilizar la adopción del Internet de las Cosas en el nivel de planta de producción, en procesos discretos, para incrementar la capacidad de uso de la información proveniente tanto de la energía como de la eficiencia energética. Para alcanzar este objetivo general, la investigación se ha dividido en cuatro sub-objetivos y la misma se ha desarrollado a lo largo de cuatro fases principales (en adelante estudios). El primer estudio de esta tesis, que se apoya sobre una revisión bibliográfica comprehensiva y sobre las aportaciones de expertos, define prácticas de gestión de la producción que son energéticamente eficientes y que se apoyan de un modo preeminente en la tecnología IoT. Este primer estudio también detalla los beneficios esperables al adoptar estas prácticas de gestión. Además, propugna un marco de referencia para permitir la integración de los datos que sobre el consumo energético se obtienen en el marco de las plataformas y sistemas de información de la compañía. Esto se lleva a cabo con el objetivo último de remarcar cómo estos datos pueden ser utilizados para apalancar decisiones en los niveles de procesos tanto tácticos como operativos. Segundo, considerando los precios de la energía como variables en el mercado intradiario y la disponibilidad de información detallada sobre el estado de las máquinas desde el punto de vista de consumo energético, el segundo estudio propone un modelo matemático para minimizar los costes del consumo de energía para la programación de asignaciones de una única máquina que deba atender a varios procesos de producción. Este modelo permite la toma de decisiones en el nivel de máquina para determinar los instantes de lanzamiento de cada trabajo de producción, los tiempos muertos, cuándo la máquina debe ser puesta en un estado de apagada, el momento adecuado para rearrancar, y para pararse, etc. Así, este modelo habilita al responsable de producción de implementar el esquema de producción menos costoso para cada turno de producción. En el tercer estudio esta investigación proporciona una metodología para ayudar a los responsables a implementar IoT en el nivel de los sistemas productivos. Se incluye un análisis del estado en que se encuentran los sistemas de gestión de energía y de producción en la factoría, así como también se proporcionan recomendaciones sobre procedimientos para implementar IoT para capturar y analizar los datos de consumo. Esta metodología ha sido validada en un estudio piloto, donde algunos indicadores clave de rendimiento (KPIs) han sido empleados para determinar la eficiencia energética. En el cuarto estudio el objetivo es introducir una vía para obtener visibilidad y relevancia a diferentes niveles de la energía consumida en los procesos de producción. El método propuesto permite que las factorías con procesos de producción discretos puedan determinar la energía consumida, el CO2 emitido o el coste de la energía consumida ya sea en cualquiera de los niveles: operación, producto o la orden de fabricación completa, siempre considerando las diferentes fuentes de energía y las fluctuaciones en los precios de la misma. Los resultados muestran que decisiones y prácticas de gestión para conseguir sistemas de producción energéticamente eficientes son posibles en virtud del Internet de las Cosas. También, con los resultados de esta tesis los responsables de la gestión energética en las compañías pueden plantearse una aproximación a la utilización del IoT desde un punto de vista de la obtención de beneficios, abordando aquellas prácticas de gestión energética que se encuentran más próximas al nivel de madurez de la factoría, a sus objetivos, al tipo de producción que desarrolla, etc. Así mismo esta tesis muestra que es posible obtener reducciones significativas de coste simplemente evitando los períodos de pico diario en el precio de la misma. Además la tesis permite identificar cómo el nivel de monitorización del consumo energético (es decir al nivel de máquina), el intervalo temporal, y el nivel del análisis de los datos son factores determinantes a la hora de localizar oportunidades para mejorar la eficiencia energética. Adicionalmente, la integración de datos de consumo energético en tiempo real con datos de producción (cuando existen altos niveles de estandarización en los procesos productivos y sus datos) es esencial para permitir que las factorías detallen la energía efectivamente consumida, su coste y CO2 emitido durante la producción de un producto o componente. Esto permite obtener una valiosa información a los gestores en el nivel decisor de la factoría así como a los consumidores y reguladores. ABSTRACT In today‘s manufacturing scenario, rising energy prices, increasing ecological awareness, and changing consumer behaviors are driving decision makers to prioritize green manufacturing. The Internet of Things (IoT) paradigm promises to increase the visibility and awareness of energy consumption, thanks to smart sensors and smart meters at the machine and production line level. Consequently, real-time energy consumption data from the manufacturing processes can be easily collected and then analyzed, to improve energy-aware decision-making. This thesis aims to investigate how to utilize the adoption of the Internet of Things at shop floor level to increase energy–awareness and the energy efficiency of discrete production processes. In order to achieve the main research goal, the research is divided into four sub-objectives, and is accomplished during four main phases (i.e., studies). In the first study, by relying on a comprehensive literature review and on experts‘ insights, the thesis defines energy-efficient production management practices that are enhanced and enabled by IoT technology. The first study also explains the benefits that can be obtained by adopting such management practices. Furthermore, it presents a framework to support the integration of gathered energy data into a company‘s information technology tools and platforms, which is done with the ultimate goal of highlighting how operational and tactical decision-making processes could leverage such data in order to improve energy efficiency. Considering the variable energy prices in one day, along with the availability of detailed machine status energy data, the second study proposes a mathematical model to minimize energy consumption costs for single machine production scheduling during production processes. This model works by making decisions at the machine level to determine the launch times for job processing, idle time, when the machine must be shut down, ―turning on‖ time, and ―turning off‖ time. This model enables the operations manager to implement the least expensive production schedule during a production shift. In the third study, the research provides a methodology to help managers implement the IoT at the production system level; it includes an analysis of current energy management and production systems at the factory, and recommends procedures for implementing the IoT to collect and analyze energy data. The methodology has been validated by a pilot study, where energy KPIs have been used to evaluate energy efficiency. In the fourth study, the goal is to introduce a way to achieve multi-level awareness of the energy consumed during production processes. The proposed method enables discrete factories to specify energy consumption, CO2 emissions, and the cost of the energy consumed at operation, production and order levels, while considering energy sources and fluctuations in energy prices. The results show that energy-efficient production management practices and decisions can be enhanced and enabled by the IoT. With the outcomes of the thesis, energy managers can approach the IoT adoption in a benefit-driven way, by addressing energy management practices that are close to the maturity level of the factory, target, production type, etc. The thesis also shows that significant reductions in energy costs can be achieved by avoiding high-energy price periods in a day. Furthermore, the thesis determines the level of monitoring energy consumption (i.e., machine level), the interval time, and the level of energy data analysis, which are all important factors involved in finding opportunities to improve energy efficiency. Eventually, integrating real-time energy data with production data (when there are high levels of production process standardization data) is essential to enable factories to specify the amount and cost of energy consumed, as well as the CO2 emitted while producing a product, providing valuable information to decision makers at the factory level as well as to consumers and regulators.

Dynamic analysis of physiological properties of Torulaspora delbrueckii in wine fermentations and its incidence on wine quality

This work examines the physiology of a new commercial strain of Torulaspora delbrueckii in the production of red wine following different combined fermentation strategies. For a detailed comparison, several yeast metabolites and the strains implantation were measured over the entire fermentation period. In all fermentations in which T. delbrueckii was involved, the ethanol concentration was reduced; some malic acid was consumed; more pyruvic acid was released, and fewer amounts of higher alcohols were produced. The sensorial properties of final wines varied widely, emphasising the structure of wine in sequential fermentations with T. delbrueckii. These wines presented the maximum overall impression and were preferred by tasters. Semi-industrial assays were carried out confirming these differences at a higher scale. No important differences were observed in volatile aroma composition between fermentations. However, differences in mouthfeel properties were observed in semi-industrial fermentations, which were correlated with an increase in the mannoprotein content of red wines fermented sequentially with T. delbrueckii.

Improved ore processing assessed by digital image análisis of the ores: a key to the sustainable development of the Iberian Pyrite Belt

Mining in the Iberian Pyrite Belt (IPB), the biggest VMS metallogenetic province known in the world to date, has to face a deep crisis in spite of the huge reserves still known after ≈5 000 years of production. This is due to several factors, as the difficult processing of complex Cu-Pb-Zn-Ag- Au ores, the exhaustion of the oxidation zone orebodies (the richest for gold, in gossan), the scarce demand for sulphuric acid in the world market, and harder environmental regulations. Of these factors, only the first and the last mentioned can be addressed by local ore geologists. A reactivation of mining can therefore only be achieved by an improved and more efficient ore processing, under the constraint of strict environmental controls. Digital image analysis of the ores, coupled to reflected light microscopy, provides a quantified and reliable mineralogical and textural characterization of the ores. The automation of the procedure for the first time furnishes the process engineers with real-time information, to improve the process and to preclude or control pollution; it can be applied to metallurgical tailings as well. This is shown by some examples of the IPB.

Assessment of Hydrogen as suistinable clean energy

The progressive depletion of fossil fuels and their high contribution to the energy supply in this modern society forces that will be soon replaced by renewable fuels. But the dispersion and alternation of renewable energy production also undertake to reduce their costs to use as energy storage and hydrogen carrier. It is necessary to develop technologies for hydrogen production from all renewable energy storage technologies and the development of energy production from hydrogen fuel cells and cogeneration and tri generation systems. In order to propel this technological development discussed where the hydrogen plays a key role as energy storage and renewable energy, the National Centre of Hydrogen and Fuel Cell Technology Experimentation in Spain equipped with installations that enable scientific and technological design, develop, verify, certify, approve, test, measure and, more importantly, the facility ensures continuous operation for 24 hours a day, 365 days year. At the same time, the system is scalable so as to allow continuous adaptation of new technologies are developed and incorporated into the assembly to verify integration at the same time it checks the validity of their development. The transformation sector can be said to be the heart of the system, because without neglecting the other sectors, this should prove the validity of hydrogen as a carrier - energy storage are important efforts that have to do to demonstrate the suitability of fuel cells or internal combustion systems to realize the energy stored in hydrogen at prices competitive with conventional systems. The multiple roles to meet the fuel cells under different conditions of operation require to cover their operating conditions, many different sizes and applications. The fourth area focuses on integration is an essential complement within the installation. We must integrate not only the electricity produced, but also hydrogen is used and the heat generated in the process of using hydrogen energy. The energy management in its three forms: hydrogen chemical, electrical and thermal integration requires complicated and require a logic and artificial intelligence extremes to ensure maximum energy efficiency at the same time optimum utilization is achieved. Verification of the development and approval in the entire production system and, ultimately, as a demonstrator set to facilitate the simultaneous evolution of production technology, storage and distribution of hydrogen fuel cells has been assessed.

Nutritional impact on health and performance in intensively reared rabbits

The present work summarizes research related to the definition of nutrient recommendations for feeds used in the intensive production of rabbit's meat. Fibre is the main chemical constituent of rabbit diets that typically contain 320 to 360 and 50 to 90 g/kg of insoluble and soluble fibre, respectively. Instead, the dietary contents of cereal grains (∼120 to 160 g/kg), fat (15 to 25 g/kg) and protein concentrates (150 to 180 g/kg) are usually low with respect to other intensively reared monogastric animals. Cell wall constituents are not well digested in rabbits, but this effect is compensated by its stimulus of gut motility, which leads to an increasing rate of passage of digesta, and allows achieving an elevated dry matter intake. A high feed consumption and an adequate balance in essential nutrients are required to sustain the elevated needs of high-productive rabbits measured either as reproductive yield, milk production or growth rate in the fattening period. Around weaning, pathologies occur in a context of incomplete development of the digestive physiology of young rabbits. The supply of balanced diets has also been related to the prevention of disorders by means of three mechanisms: (i) promoting a lower retention time of the digesta in the digestive tract through feeding fibre sources with optimal chemical and physical characteristics, (ii) restricting feed intake after weaning or (iii) causing a lower flow of easily available substrates into the fermentative area by modifying feed composition (e.g. by lowering protein and starch contents, increasing its digestibility or partially substituting insoluble with soluble fibre), or by delaying age at weaning. The alteration in the gut microbiota composition has been postulated as the possible primary cause of these pathologies.

A generator of efficient abstract machine implementations and its application to emulator minimization

The implementation of abstract machines involves complex decisions regarding, e.g., data representation, opcodes, or instruction specialization levéis, all of which affect the final performance of the emulator and the size of the bytecode programs in ways that are often difficult to foresee. Besides, studying alternatives by implementing abstract machine variants is a time-consuming and error-prone task because of the level of complexity and optimization of competitive implementations, which makes them generally difficult to understand, maintain, and modify. This also makes it hard to genérate specific implementations for particular purposes. To ameliorate those problems, we propose a systematic approach to the automatic generation of implementations of abstract machines. Different parts of their definition (e.g., the instruction set or the infernal data and bytecode representation) are kept sepárate and automatically assembled in the generation process. Alternative versions of the abstract machine are therefore easier to produce, and variants of their implementation can be created mechanically, with specific characteristics for a particular application if necessary. We illustrate the practicality of the approach by reporting on an implementation of a generator of production-quality WAMs which are specialized for executing a particular fixed (set of) program(s). The experimental results show that the approach is effective in reducing emulator size.

Sensing colour stability and mixtures of powder paprika using optical reflectance and image analysis.

The production and industry of paprika present several problems related to quality and to production costs. One of the main difficulties is to obtain an objective and quick method for predicting quality. Quality in powder paprika involves: quantity of carotenoids and the appearance and stability of colour. The method used currently for determining quality is the measurement of absorbance at 460 nm wavelength, of an acetone extract of carotenoids, but there is no information about the appearance of the paprika or the stability of its colour with time. " Another important problem is the presence of mixtures of powdered paprika produced in the Spanish region of "La Vera", which has a peculiar way of production, with a high '' quality and price, with other products of lower quality. It is necessary to obtain methods which are able to detect the fraud.

Fish physiology put into practice: A robotic fish model

Underwater creatures are capable of high performance movements in water. Thus, underwaterrobot design based on the mechanism of fish locomotion appears to be a promising approach.Over the past few years, researches have been developing underwater robots based on underwatercreatures swimming mechanism.

Integration of physical, chemical and biological tactics against insect pests and virus diseases in horticultural crops

Actualmente, la gestión de sistemas de Manejo Integrado de Plagas (MIP) en cultivos hortícolas tiene por objetivo priorizar los métodos de control no químicos en detrimento del consumo de plaguicidas, según recoge la directiva europea 2009/128/CE ‘Uso Sostenible de Plaguicidas’ (OJEC, 2009). El uso de agentes de biocontrol como alternativa a la aplicación de insecticidas es un elemento clave de los sistemas MIP por sus innegables ventajas ambientales que se utiliza ampliamente en nuestro país (Jacas y Urbaneja, 2008). En la región de Almería, donde se concentra el 65% de cultivo en invernadero de nuestro país (47.367 ha), MIP es la principal estrategia en pimiento (MAGRAMA, 2014), y comienza a serlo en otros cultivos como tomate o pepino. El cultivo de pepino, con 8.902 ha (MAGRAMA, 2013), tiene un protocolo semejante al pimiento (Robledo et al., 2009), donde la única especie de pulgón importante es Aphis gossypii Glover. Sin embargo, pese al continuo incremento de la superficie de cultivo agrícola bajo sistemas MIP, los daños originados por virosis siguen siendo notables. Algunos de los insectos presentes en los cultivos de hortícolas son importantes vectores de virus, como los pulgones, las moscas blancas o los trips, cuyo control resulta problemático debido a su elevada capacidad para transmitir virus vegetales incluso a una baja densidad de plaga (Holt et al., 2008; Jacas y Urbaneja, 2008). Las relaciones que se establecen entre los distintos agentes de un ecosistema son complejas y muy específicas. Se ha comprobado que, pese a que los enemigos naturales reducen de manera beneficiosa los niveles de plaga, su incorporación en los sistemas planta-insecto-virus puede desencadenar complicadas interacciones con efectos no deseables (Dicke y van Loon, 2000; Jeger et al., 2011). Así, los agentes de biocontrol también pueden inducir a que los insectos vectores modifiquen su comportamiento como respuesta al ataque y, con ello, el grado de dispersión y los patrones de distribución de las virosis que transmiten (Bailey et al., 1995; Weber et al., 1996; Hodge y Powell, 2008a; Hodge et al., 2011). Además, en ocasiones el control biológico por sí solo no es suficiente para controlar determinadas plagas (Medina et al., 2008). Entre los métodos que se pueden aplicar bajo sistemas MIP están las barreras físicas que limitan la entrada de plagas al interior de los invernaderos o interfieren con su movimiento, como pueden ser las mallas anti-insecto (Álvarez et al., 2014), las mallas fotoselectivas (Raviv y Antignus, 2004; Weintraub y Berlinger, 2004; Díaz y Fereres, 2007) y las mallas impregnadas en insecticida (Licciardi et al., 2008; Martin et al., 2014). Las mallas fotoselectivas reducen o bloquean casi por completo la transmisión de radiación UV, lo que interfiere con la visión de los insectos y dificulta o impide la localización del cultivo y su establecimiento en el mismo (Raviv y Antignus, 2004; Weintraub, 2009). Se ha comprobado cómo su uso puede controlar los pulgones y las virosis en cultivo de lechuga (Díaz et al., 2006; Legarrea et al., 2012a), así como la mosca blanca, los trips y los ácaros, y los virus que estos transmiten en otros cultivos (Costa y Robb, 1999; Antignus et al., 2001; Kumar y Poehling, 2006; Doukas y Payne, 2007a; Legarrea et al., 2010). Sin embargo, no se conoce perfectamente el modo de acción de estas barreras, puesto que existe un efecto directo sobre la plaga y otro indirecto mediado por la planta, cuya fisiología cambia al desarrollarse en ambientes con falta de radiación UV, y que podría afectar al ciclo biológico de los insectos fitófagos (Vänninen et al., 2010; Johansen et al., 2011). Del mismo modo, es necesario estudiar la compatibilidad de esta estrategia con los enemigos naturales de las plagas. Hasta la fecha, los estudios han evidenciado que los agentes de biocontrol pueden realizar su actividad bajo ambientes pobres en radiación UV (Chyzik et al., 2003; Chiel et al., 2006; Doukas y Payne, 2007b; Legarrea et al., 2012c). Otro método basado en barreras físicas son las mallas impregnadas con insecticidas, que se han usado tradicionalmente en la prevención de enfermedades humanas transmitidas por mosquitos (Martin et al., 2006). Su aplicación se ha ensayado en agricultura en ciertos cultivos al aire libre (Martin et al., 2010; Díaz et al., 2004), pero su utilidad en cultivos protegidos para prevenir la entrada de insectos vectores en invernadero todavía no ha sido investigada. Los aditivos se incorporan al tejido durante el proceso de extrusión de la fibra y se liberan lentamente actuando por contacto en el momento en que el insecto aterriza sobre la malla, con lo cual el riesgo medioambiental y para la salud humana es muy limitado. Los plaguicidas que se emplean habitualmente suelen ser piretroides (deltametrina o bifentrín), aunque también se ha ensayado dicofol (Martin et al., 2010) y alfa-cipermetrina (Martin et al., 2014). Un factor que resulta de vital importancia en este tipo de mallas es el tamaño del poro para facilitar una buena ventilación del cultivo, al tiempo que se evita la entrada de insectos de pequeño tamaño como las moscas blancas (Bethke y Paine, 1991; Muñoz et al., 1999). Asimismo, se plantea la necesidad de estudiar la compatibilidad de estas mallas con los enemigos naturales. Es por ello que en esta Tesis Doctoral se plantea la necesidad de evaluar nuevas mallas impregnadas que impidan el paso de insectos de pequeño tamaño al interior de los invernaderos, pero que a su vez mantengan un buen intercambio y circulación de aire a través del poro de la malla. Así, en la presente Tesis Doctoral, se han planteado los siguientes objetivos generales a desarrollar: 1. Estudiar el impacto de la presencia de parasitoides sobre el grado de dispersión y los patrones de distribución de pulgones y las virosis que éstos transmiten. 2. Conocer el efecto directo de ambientes pobres en radiación UV sobre el comportamiento de vuelo de plagas clave de hortícolas y sus enemigos naturales. 3. Evaluar el efecto directo de la radiación UV-A sobre el crecimiento poblacional de pulgones y mosca blanca, y sobre la fisiología de sus plantas hospederas, así como el efecto indirecto de la radiación UV-A en ambas plagas mediado por el crecimiento de dichas planta hospederas. 4. Caracterización de diversas mallas impregnadas en deltametrina y bifentrín con diferentes propiedades y selección de las óptimas para el control de pulgones, mosca blanca y sus virosis asociadas en condiciones de campo. Estudio de su compatibilidad con parasitoides. ABSTRACT Insect vectors of plant viruses are the main agents causing major economic losses in vegetable crops grown under protected environments. This Thesis focuses on the implementation of new alternatives to chemical control of insect vectors under Integrated Pest Management programs. In Spain, biological control is the main pest control strategy used in a large part of greenhouses where horticultural crops are grown. The first study aimed to increase our knowledge on how the presence of natural enemies such as Aphidius colemani Viereck may alter the dispersal of the aphid vector Aphis gossypii Glover (Chapter 4). In addition, it was investigated if the presence of this parasitoid affected the spread of aphid-transmitted viruses Cucumber mosaic virus (CMV, Cucumovirus) and Cucurbit aphid-borne yellows virus (CABYV, Polerovirus) infecting cucumber (Cucumis sativus L). SADIE methodology was used to study the distribution patterns of both the virus and its vector, and their degree of association. Results suggested that parasitoids promoted aphid dispersal in the short term, which enhanced CMV spread, though consequences of parasitism suggested potential benefits for disease control in the long term. Furthermore, A. colemani significantly limited the spread and incidence of the persistent virus CABYV in the long term. The flight activity of pests Myzus persicae (Sulzer), Bemisia tabaci (Gennadius) and Tuta absoluta (Meyrick), and natural enemies A. colemani and Sphaerophoria rueppellii (Weidemann) under UV-deficient environments was studied under field conditions (Chapter 5). One-chamber tunnels were covered with cladding materials with different UV transmittance properties. Inside each tunnel, insects were released from tubes placed in a platform suspended from the ceiling. Specific targets were located at different distances from the platform. The ability of aphids and whiteflies to reach their targets was diminished under UV-absorbing barriers, suggesting a reduction of vector activity under this type of nets. Fewer aphids reached distant traps under UV-absorbing nets, and significantly more aphids could fly to the end of the tunnels covered with non-UV blocking materials. Unlike aphids, differences in B. tabaci captures were mainly found in the closest targets. The oviposition of lepidopteran T. absoluta was also negatively affected by a UV-absorbing cover. The photoselective barriers were compatible with parasitism and oviposition of biocontrol agents. Apart from the direct response of insects to UV radiation, plant-mediated effects influencing insect performance were investigated (Chapter 6). The impact of UV-A radiation on the performance of aphid M. persicae and whitefly B. tabaci, and growth and leaf physiology of host plants pepper and eggplant was studied under glasshouse conditions. Plants were grown inside cages covered by transparent and UV-A-opaque plastic films. Plant growth and insect fitness were monitored. Leaves were harvested for chemical analysis. Pepper plants responded directly to UV-A by producing shorter stems whilst UV-A did not affect the leaf area of either species. UV-A-treated peppers had higher content of secondary metabolites, soluble carbohydrates, free amino acids and proteins. Such changes in tissue chemistry indirectly promoted aphid performance. For eggplants, chlorophyll and carotenoid levels decreased with supplemental UVA but phenolics were not affected. Exposure to supplemental UV-A had a detrimental effect on whitefly development, fecundity and fertility presumably not mediated by plant cues, as compounds implied in pest nutrition were unaltered. Lastly, the efficacy of a wide range of Long Lasting Insecticide Treated Nets (LLITNs) was studied under laboratory and field conditions. This strategy aimed to prevent aphids and whiteflies to enter the greenhouse by determining the optimum mesh size (Chapter 7). This new approach is based on slow release deltamethrin- and bifenthrin-treated nets with large hole sizes that allow improved ventilation of greenhouses. All LLITNs produced high mortality of M. persicae and A. gossypii although their efficacy decreased over time with sun exposure. It was necessary a net with hole size of 0.29 mm2 to exclude B. tabaci under laboratory conditions. The feasibility of two selected nets was studied in the field under a high insect infestation pressure in the presence of CMV- and CABYV-infected cucumber plants. Besides, the compatibility of parasitoid A. colemani with bifenthrin-treated nets was studied in parallel field experiments. Both nets effectively blocked the invasion of aphids and reduced the incidence of both viruses, however they failed to exclude whiteflies. We found that our LLITNs were compatible with parasitoid A. colemani. As shown, the role of natural enemies has to be taken into account regarding the dispersal of insect vectors and subsequent spread of plant viruses. The additional benefits of novel physicochemical barriers, such as photoselective and insecticide-impregnated nets, need to be considered in Integrated Pest Management programs of vegetable crops grown under protected environments.

Exploring the economic value of personal information from firms' financial statements

Currently personal data gathering in online markets is done on a far larger scale and much cheaper and faster than ever before. Within this scenario, a number of highly relevant companies for whom personal data is the key factor of production have emerged. However, up to now, the corresponding economic analysis has been restricted primarily to a qualitative perspective linked to privacy issues. Precisely, this paper seeks to shed light on the quantitative perspective, approximating the value of personal information for those companies that base their business model on this new type of asset. In the absence of any systematic research or methodology on the subject, an ad hoc procedure is developed in this paper. It starts with the examination of the accounts of a number of key players in online markets. This inspection first aims to determine whether the value of personal information databases is somehow reflected in the firms’ books, and second to define performance measures able to capture this value. After discussing the strengths and weaknesses of possible approaches, the method that performs best under several criteria (revenue per data record) is selected. From here, an estimation of the net present value of personal data is derived, as well as a slight digression into regional differences in the economic value of personal information.

Can small horticulture crops improve family farm incomes in mountains areas of Central America?

Small family farm in mountain areas can found in horticulture one alternative to increase incomes. Horticulture crop required more labour and increased the land intensification. Market of production will be the key factor in the future of this family farms.