Under which conditions is carrier cooperation possible? A case study in a Seville marketplace

The high volume of traffic originates two well-known problems in many cities: congestion and pollution. In recent years, a social phenomenon is emerging cooperation. This work is aimed at evaluating the circumstances under which transport cooperation is possible between different stakeholders operating in the same geographical area. To this end, a double survey process was conducted in a marketplace situated in the Seville City (Spain) centre. The first survey was designed to know the characteristics of the retailers and their preferences with respect to cooperation and regulations. A relational analysis between retailer features and their willingness to cooperate was carried out. After analysing the motivations for non-cooperation, a mixed proposal was designed and surveyed. Although the research was limited to a marketplace, the relevant data gathered from this double survey process highlights some implications: (a) the importance of personal relations in retailer cooperation; (b) a high volume of freight and the use of vans as on-street warehouses appear as significant motivations for non-cooperation; (c) forcing changes in the statu quo encourages cooperation.Ministerio de Economía y Competitividad (España) TEC2013-47286-C3-3-

Predicción de la frescura del aceite de oliva virgen extra durante el almacenamiento mediante espectroscopía de fluorescencia

Virgin olive oil quality relates to flavor and unique health benefits. Some of these properties are at the most desirable level when the oil is just extracted, since it is not a product that improves with age. On the contrary, the concentrations of many compounds change during its shelf-life. These changes reveal the aging of the oil but do not necessarily mean decay in sensory properties, so in some cases an aged oil from healthy olives may be better qualified than a fresh one from olives affected by fermentation. The aim of this work is to analyze different methodologies proposed for assessing the quality of virgin olive oil with implications in freshness and aging of the oil, and to highlight the possibilities of rapid spectrofluorimetric techniques for assessing oil freshness by checking the evolution of pigments during storage. The observed change in the selected spectral features and mathematical modelling over time was compared with the accepted model for predicting the amount of pyropheophytin a, which is based on isokinetic studies. The best regression was obtained for 655 nm (adjustedR2 = 0.91) wavelength, which matches the distinctive band of pigments. The two mathematical models described in this study highlight the usefulness of pigments in the prediction of the shelf-life of extra virgin olive oil.La calidad del aceite de oliva virgen está relacionada con su flavor y sus beneficios únicos para la salud. Algunas de estas propiedades se encuentran en el nivel más deseable cuando el aceite está recién extraído, ya que no es un producto que mejore con el tiempo. Por el contrario, las concentraciones de muchos compuestos cambian a lo largo de la vida útil. Estos cambios revelan el envejecimiento del aceite, pero no implican necesariamente la alteración de las propiedades sensoriales, por lo que en algunos casos un aceite envejecido procedente de aceitunas sanas puede presentar mejor calidad que uno fresco procedente de aceitunas afectadas por procesos de fermentación. El objetivo de este trabajo es estudiar diferentes metodologías propuestas para evaluar la calidad del aceite de oliva virgen con implicaciones en la frescura y el envejecimiento del aceite, destacando las posibilidades de las rápidas técnicas espectrofluorométricas para evaluar la frescura del aceite verificando la evolución de los pigmentos durante el almacenamiento. El cambio observado en las características espectrales seleccionadas y su modelado matemático a lo largo del tiempo se comparó con el modelo aceptado para predecir la cantidad de pirofeofitina a, que se basa en estudios isocinéticos. Los dos modelos matemáticos descritos en este estudio pusieron de manifiesto la utilidad de los pigmentos en la predicción de la vida útil del aceite de oliva virgen extra. La mejor regresión se obtuvo para 655 nm (R2 -ajustado = 0,91), longitud de onda que coincide con la banda distintiva de pigmentos.Secretaría de Estado de Investigación, Desarrollo e Innovación de España-AGL2015-69320-

Predicción de la frescura del aceite de oliva virgen extra durante el almacenamiento mediante espectroscopía de fluorescencia

Virgin olive oil quality relates to flavor and unique health benefits. Some of these properties are at the most desirable level when the oil is just extracted, since it is not a product that improves with age. On the contrary, the concentrations of many compounds change during its shelf-life. These changes reveal the aging of the oil but do not necessarily mean decay in sensory properties, so in some cases an aged oil from healthy olives may be better qualified than a fresh one from olives affected by fermentation. The aim of this work is to analyze different methodologies proposed for assessing the quality of virgin olive oil with implications in freshness and aging of the oil, and to highlight the possibilities of rapid spectrofluorimetric techniques for assessing oil freshness by checking the evolution of pigments during storage. The observed change in the selected spectral features and mathematical modelling over time was compared with the accepted model for predicting the amount of pyropheophytin a, which is based on isokinetic studies. The best regression was obtained for 655 nm (adjustedR2 = 0.91) wavelength, which matches the distinctive band of pigments. The two mathematical models described in this study highlight the usefulness of pigments in the prediction of the shelf-life of extra virgin olive oil.La calidad del aceite de oliva virgen está relacionada con su flavor y sus beneficios únicos para la salud. Algunas de estas propiedades se encuentran en el nivel más deseable cuando el aceite está recién extraído, ya que no es un producto que mejore con el tiempo. Por el contrario, las concentraciones de muchos compuestos cambian a lo largo de la vida útil. Estos cambios revelan el envejecimiento del aceite, pero no implican necesariamente la alteración de las propiedades sensoriales, por lo que en algunos casos un aceite envejecido procedente de aceitunas sanas puede presentar mejor calidad que uno fresco procedente de aceitunas afectadas por procesos de fermentación. El objetivo de este trabajo es estudiar diferentes metodologías propuestas para evaluar la calidad del aceite de oliva virgen con implicaciones en la frescura y el envejecimiento del aceite, destacando las posibilidades de las rápidas técnicas espectrofluorométricas para evaluar la frescura del aceite verificando la evolución de los pigmentos durante el almacenamiento. El cambio observado en las características espectrales seleccionadas y su modelado matemático a lo largo del tiempo se comparó con el modelo aceptado para predecir la cantidad de pirofeofitina a, que se basa en estudios isocinéticos. Los dos modelos matemáticos descritos en este estudio pusieron de manifiesto la utilidad de los pigmentos en la predicción de la vida útil del aceite de oliva virgen extra. La mejor regresión se obtuvo para 655 nm (R2 -ajustado = 0,91), longitud de onda que coincide con la banda distintiva de pigmentos.Secretaría de Estado de Investigación, Desarrollo e Innovación de España-AGL2015-69320-

A viral system to optimise the daily drayage problem

The intermodal transport chain can become more efficient by means of a good organisation of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. This paper focuses on a new approach to tackle the daily drayage problem by the use of viral system (VS). VS is a novel bio-inspired approach that makes use of a virus-infection biological analogy that is producing very satisfactory results when dealing with complex problems with huge feasibility region.Unión Europea TEC2013-47286-C3-3-

El termómetro de globo en estudios de confort y medioambiente en los edificios

The reasons for the inferior performance of many existing buildings and associated energy systems are diverse, but an important part-cause is insufficient attention to the influence of occupant behaviour. In smart buildings it is necessary to allow for the integration of human behaviour in the HVAC system. In addition, many researchers are limited in their investigation by not having low cost tools that can provide information for their studies. This article is a review of the present state of art about the globe thermometer. It describes how to build your own globe temperature sensor and describes experiments that illustrate the feasibility of using a black globe thermometer with 40 mm diameter.Las razones del rendimiento inferior de muchos de los edificios actuales y sus sistemas energéticos relacionados son diversas y estas son en una parte importante causada por una atención insuficiente a la influencia del comportamiento de los ocupantes. En los edificios inteligentes es necesario implementar nuevas oportunidades para integrar el comportamiento humano en el sistema de climatización. Además, muchos investigadores están limitados en su investigación al no contar con herramientas de bajo coste que puedan proporcionar información a sus estudios. En este artículo se presenta una revisión del estado actual del arte sobre el termómetro de globo, se describe cómo construir su propio sensor de temperatura de globo y los experimentos descritos ilustran la viabilidad de utilizar un termómetro de globo negro con 40 mm de diámetro

Decoloration kinetics of chlorophylls and carotenoids in virgin olive oil by autoxidation

© 2014 Elsevier Ltd. Kinetic models are capable of predicting shelf life in keeping with the different variables that can affect the degradation of the food item. In this work, virgin olive oils (VOOs) extracted from olive fruits at three ripening stages with high, medium and low pigment contents respectively, were thermodegraded to characterize the kinetic and thermodynamic parameters for the oxidation of two pigment fractions: a green fraction (chlorophylls) and a yellow fraction (carotenoids). A first-order kinetic mechanism was appropriate for describing the decoloration processes under non-oxygen thermal auto-oxidation. A marked effect of temperature has been pointed out, with the carotenoids (CARs) being the most affected by heat. The kinetic constants for the CAR degradation were about 3.6 times higher than the respective constants for chlorophylls (CHLs) that showed a more stable structure to decoloration by heat. As well, higher activation energy of CHLs (16.03±0.26kcal·mol-1) as compared to CARs (15.45±0.17kcal·mol-1) implies that a smaller temperature change is needed to increase the kinetic constant of CHLs.Neither isokinetic ratio nor compensation existed between the three VOO matrixes and further, for each pigment fraction (CHLs or CARs) all kinetic constants were explained by a single Arrhenius line. Consequently, the differences between the oily matrixes did not significantly affect the decoloration mechanisms, and moreover, the kinetic parameters obtained as temperature functions according to the Arrhenius model, can be used to develop a prediction mathematical model for decoloration of CHL and CAR pigment fractions in VOO over time and depending on temperature.This work was supported by the Comision Interministerial de Ciencia y Tecnología (CICYT-EU, Spanish and European Governments) under the research project AGL 2012-39714/ALI and by the Junta de Andalucía in the Project AGR 2010-6271 and through the financial support to the group AGR 148-2012. We thank Cooperativa Sor Ángela de la Cruz (Estepa, Sevilla) for supplying the oil samples. The authors are members of the IBERCAROT Network, funded by CYTED (ref. 112RT0445).Peer Reviewe