1,552 research outputs found
The influence of career choice intentions on new venture creation in Algeria, Sierra Leone, and South Africa
This paper analyses the influence that career choice intentions, including entrepreneurial intentions, have on new venture creation among African university students. In addition to that, we explore how social context may affect new venture creation, considering the inner circle of entrepreneurs, the organizational environment and the broader environment. To test our hypotheses, we used data from the 2018 Global University Entrepreneurial Spirit Students’ Survey (GUESSS), focusing on university students from Algeria, Sierra Leone and South Africa. Our findings provide evidence that, in these countries, career choice intentions to become an entrepreneur —either immediately after graduation or five years after graduation— are a good predictor of current new venture creation by university students. We also found an important role of the effectiveness of entrepreneurship education courses for determining new venture creation. Our investigation contributes to filling the gap in the link between career choice intentions and entrepreneurial behavior in Africa.info:eu-repo/semantics/acceptedVersio
Evaluation of alternative policies of water price for the agricultural use in Alentejo Region
Irrigation is economically important in many regions of Mediterranean Europe such as the Portuguese region of
Alentejo. The new Water Law proposed by the European Commission, pointing out that water management
might be based on the principle of payment by users. These issues have some effect on the cost pattern of the
farmers, when considering the water cost. However, the implementation of water tariff policies can provide a
very important policy instrument, in order to promote an efficient use of water in agricultural sector as well as to
avoid, at least partially, the loss of farm incomes. The main objective of this study is to evaluate the effects of
alternative policies of water price for agriculture use in the farm income and the production pattern, having in
account the recovery of the public investment and the operating costs with irrigation infrastructures. The
methodology used is based, on the one hand, on the estimate of farm water demand and, on the other hand on
the determination of the investment and on the current costs of the irrigation infrastructures. This study was
applied to irrigated areas of Odivelas, in the South of Portuga
Generate disaggregated soil allocation data using a Minimum Cross Entropy Model
Montado ecosystem in the Alentejo Region, south of Portugal, has enormous agro-ecological and economics heterogeneities. A definition of homogeneous sub-units among this heterogeneous ecosystem was made, but for them is disposal only partial statistical information about soil allocation agro-forestry activities. The paper proposal is to recover the unknown soil allocation at each homogeneous sub-unit, disaggregating a complete data set for the Montado ecosystem area using incomplete information at sub-units level. The methodological framework is based on a Generalized Maximum Entropy approach, which is developed in thee steps concerning the specification of a r order Markov process, the estimates of aggregate transition probabilities and the disaggregation data to recover the unknown soil allocation at each homogeneous sub-units. The results quality is evaluated using the predicted absolute deviation (PAD) and the "Disagegation Information Gain" (DIG) and shows very acceptable estimation errors
Influencia del tipo de derivado celulósico sobre la textura y la estabilidad oxidativa y térmica de oleogeles de aceite de soja
The use oleogels (defined as edible oils entrapped in a three-dimensional network employing a self-assembled structuring agent) has recently been proposed to replace saturated fat or trans-fats in foods. In this work the effects of different cellulose derivative mixtures (Avicel, ethyl cellulose and α-cellulose) on lipid stability, glass transition temperature and the texture of soybean oil oleogels were determined by employing a mixture design approach. Avicel affected lipid stability, increasing the oxidative rancidity and peroxide values of oleogels. Oleogels with higher proportions of Avicel also presented higher transition temperatures. A higher percent of ethyl cellulose and α-cellulose in the oleogel mixture resulted in a more stable system with lower oil rancidity and lower glass transition temperatures. In addition, Avicel resulted in a softer and less tacky texture, an important characteristic to consider for food applications.Recientemente, ha sido propuesto el uso de oleogeles (definido como aceites comestibles atrapados en una red tridimensional que ocupa un agente estructurante de auto-ensamblado) como substituto de grasa saturada o grasas trans en alimentos. En este trabajo el efecto de mezclas de diferentes derivados celulósicos (Avicel, etil celulosa y α-celulosa) sobre la estabilidad de lípidos, temperaturas de transición térmica y textura de oleogeles de aceite de soja fueron determinados utilizando un diseño de mezclas. Avicel afectó la estabilidad de lípidos, aumentando la rancidez oxidativa y valores de peróxido en los oleogeles. Oleogeles con mayores proporciones de Avicel también presentaron temperaturas de transición térmica más altas. Porcentajes más altos de etil celulosa y α-celulosa resultaron en un sistema más estable con menor rancidez oxidativa y menores temperaturas de transición térmica. Sin embargo, Avicel resultó en una textura más suave y menos pegajosa, una característica importante a considerar para su aplicación en alimentos
Performance of Iris pseudacorus and Typha domingensis for furosemide removal in a hydroponic system
The potential of Iris pseudacorus and Typha domingensis to remove the pharmaceutical active compound
(PhAC) Furosemide from a nutrient solution was assessed. Both plants were exposed to
2mg L 1 of furosemide during 21 days and the removal of furosemide was monitored. Vessels
without furosemide were also implemented as control systems for plants development. Likewise,
unplanted vessels with furosemide were employed to assess abiotic removal mechanisms. All vessels
were covered with aluminum foil to avoid photodegradation of the compound. Both plants
showed potential to remove Furosemide, attaining, at the end of the experiment, a removal of
42.0–66.9% and 40.5–57.8%, for Typha and Iris, respectively. The plants do not presented a visible
negative stress response to the exposure to furosemide, having a positive growth rate at the end
of the experiment. Biodegradation seems to play an important role in furosemide removal, being
enhanced by the presence of the plants. The two macrophytes presented different removal behaviors,
particularly in the first 48 h of contact time. FUR removal by Iris follows a pseudo-first order
while by Typha is divide in different phases. These results indicate that different plants species
seem to have different mechanisms to remove pollutants from waterinfo:eu-repo/semantics/publishedVersio
Assessing impacts of Common Agricultural Policy changes on regional use patterns with a decision support system. An application in Southern Portugal
This paper discusses research aiming at assessing Common Agricultural Policy impacts on agriculture and
forestry. For this purpose an approach is developed that includes a linear programming model to estimate
the Positive Mathematical Programming production cost function coefficients of current agricultural–
forestry activities. It further includes a heuristic — simulated annealing — to generate solutions for each
policy scenario. This model base approach is integrated within a decision support system (DSS) for testing
purposes. The DSS further encompasses a relational database that stores agricultural–forestry technical and
economic data and a geographic information system that stores topological data of regional farm-type land
units. The DSS Graphical User Interface provides tabular and geographical reporting capabilities. Results are
discussed for an application to the Alentejo region in Southern Portugal. Results demonstrate the usefulness
and relevance of the proposed approach to assess the impact of changes in prices and in agricultural policy
on land use patterns and on forestr
Estrategias pasivas de optimización energética de la vivienda social en clima mediterráneo
The main goals of Horizon 2020 have led to the updating of the Basic Document on Energy Saving of the Technical Building Code in 2013. The demands of the new model, based on technological and construction parameters, are associated with a more extensive assessment of the architectural conditions of buildings.
This study aims to analyse the repercussion of the new regulations on Mediterranean social housing in climate zone B4. It proposes energy analysis on a basic model of a single linear block, adding different individual passive strategies relating to compactness, envelope material, solar control, solar accumulation and ventilation, analysing the improvement in energy demand, energy rating and indoor comfort. The main energy improvement actions used take into account orientation as well as the combined improvement in energy performance of the thermal envelope, ventilation rate and suitable solar protection. These lead to major reductions in energy demand and CO2 emissions while improving indoor comfort conditions.Los objetivos prioritarios del Horizonte 2020 han llevado a la actualización del Documento Básico de Ahorro de la Energía del CTE en 2013, introduciendo un nuevo modelo en las exigencias, basado en parámetros tecnológicos y constructivos, asociado a una mayor valoración de las condiciones arquitectónicas del edificio.
Este trabajo pretende analizar la repercusión del nuevo marco normativo en la vivienda social del área mediterránea, en la zona climática B4. Se plantea el análisis energético en un modelo base de bloque lineal entre medianeras al que se incorporan individualmente, distintas estrategias pasivas asociadas a la compacidad, materialidad de la envolvente, control solar, acumulación solar y ventilación, analizando la mejora de la demanda de energía, la calificación energética y el confort interior. La consideración de la orientación, junto con la combinación de la mejora de las prestaciones energéticas de la envolvente térmica, de la tasa de ventilación y de la adecuada protección solar constituyen las principales acciones de mejora energética que permiten conseguir importantes reducciones de la demanda energética, de las emisiones de CO2 y mejora del confort interior
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