999 resultados para Trails -- Catalonia -- Vallès
Resumo:
The trails formed by many ant species between nest and food source are two-way roads on which outgoing and returning workers meet and touch each other all along. The way to get back home, after grasping a food load, is to take the same route on which they have arrived from the nest. In many species such trails are chemically marked by pheromones providing orientation cues for the ants to find their way. Other species rely on their vision and use landmarks as cues. We have developed a method to stop foraging ants from shuttling on two-way trails. The only way to forage is to take two separate roads, as they cannot go back on their steps after arriving at the food or at the nest. The condition qualifies as a problem because all their orientation cues-chemical, visual or any other - are disrupted, as all of them cannot but lead the ants back to the route on which they arrived. We have found that workers of the leaf-cutting ant Atta sexdens rubropilosa can solve the problem. They could not only find the alternative way, but also used the unidirectional traffic system to forage effectively. We suggest that their ability is an evolutionary consequence of the need to deal with environmental irregularities that cannot be negotiated by means of excessively stereotyped behavior, and that it is but an example of a widespread phenomenon. We also suggest that our method can be adapted to other species, invertebrate and vertebrate, in the study of orientation, memory, perception, learning and communication.
Resumo:
In a recent ecological study of the ticks on animal trails within an area of Atlantic rainforest in south-eastern Brazil, Amblyomma aureolatum, A. brasiliense, A. incisum, A. ovale and Haemaphysalis juxtakochi were found questing on the vegetation. Most of the ticks recorded by a small, man-made dam on the forest border were A. dubitatum but a few A. brasiliense and A. cajennense, one A. incisum and one H. juxtakochi were also found. The seasonal activity of the ticks indicated that A. incisum and A. brasiliense had one generation/year. On the animal trails, most tick species and stages quested on the vegetation at a height of 30-40 cm above ground level. The questing larvae and adults of A. incisum tended to be found higher, however, with the greatest numbers recorded 40-50 cm (larvae) or 60-70 cm (adults) above ground level. Most of the adult ticks (81.1% -100%), nymphs (78.6%-100%) and larval clusters (100%) found on a forest trail remained questing at the same location over a 24-h period. Carbon-dioxide traps in the rainforest attracted, 50% of the ticks observed questing on the nearby vegetation and, curiously, the CO(2) traps set deep in the forest attracted far fewer ticks than similar traps set by the dam. The ecological relationships between the ticks, their hosts and the rainforest environment are discussed.
Resumo:
In order to evaluate the efficiency of different mammalian survey methods, we compared traditional sampling techniques (use of camera-traps on roads and artificial trails, track censuses, and direct field visualization) with an alternative sampling design (camera-traps positioned in natural areas such as natural trails and shelters). We conducted the study in a deciduous Atlantic-Forest park in southern Brazil, and additionally compared our results with a previous intensive study carried out in the same area. Our considerably smaller sampling effort (example: 336 trap.day for our camera-traps versus 2,154 trap.day for the earlier study) registered the presence of 85% of the local known species, with camera-traps being 68% efficient. Moreover, shelter camera-traps revealed a different species composition regarding most of other sampling methods. This sampling strategy involving natural forest sites was therefore able to effectively optimize the chances of evaluating species composition in a shorter period, especially with respect to lower-density and cryptic species, as well as to detect species that avoid open, disturbed sites such as roads and man-made forest trails.
Resumo:
Recent trends in technology transfer show an intensification of spin-off creation as a modality of university research commercialisation, complementary to the conventional ones, contract research and licensing. In this paper we analyse the evolution, objectives, resources and activities of a specialised unit –Technological Trampoline (TT) - in charge of new venture creation at the University of Girona (Catalonia-Spain). Based on two theoretical frameworks, Resource-based-view and Institutional Theory, we adopt a multi-dimensional approach to study the strategy of spinning-off new ventures at the University of Girona in terms of resources and activities, how this process is organised and if the outputs fit with this UdG’s objectives and the local environment. Our main contribution is an in-depth analysis of the spin-off creation unit with special emphasis on its variety of resources and activities. The results have a series of implications and recommendations at both university and TT level.
Resumo:
The spread of milk consumption was a significant change in the diet of Europeans, however it is one that has not been greatly studied with regard to the populations of Mediterranean Europe. In this article we shall analyse the ain circumstances that conditioned that process in Catalonia between the middle of the 19th century and 1936. In our study we shall argue that the consumption of milk in this area was only relevant in the 19th century in situations of illness or old age, and that it subsequently increased and acquired a new significance as a result of various factors. In particular, we shall emphasise: (a) the scientific advances in microbiology and nutrition, (b) the activities carried out by doctors and various public institutions to promote the consumption of fresh milk, and (c) the technological innovations in the milk producing sector. In Appendix 1 we show two maps representing the main territorial references that we shall mention.
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In this note we quantify to what extent indirect taxation influences and distorts prices. To do so we use the networked accounting structure of the most recent input-output table of Catalonia, an autonomous region of Spain, to model price formation. The role of indirect taxation is considered both from a classical value perspective and a more neoclassical flavoured one. We show that they would yield equivalent results under some basic premises. The neoclassical perspective, however, offers a bit more flexibility to distinguish among different tax figures and hence provide a clearer disaggregate picture of how an indirect tax ends up affecting, and by how much, the cost structure.
Resumo:
Estudi elaborat a partir d’una estada a la School of Modern Languages de la University of London, Gran Bretanya, entre agost i desembre del 2006. L’objectiu de la recerca consisteix en exposar el moviment empirista a través de Hume, Locke, Berkeley i altres filòsofs del segle XVIII. A més, s’analitza la filosofia escocesa del sentit comú, ja que va influenciar la filosofia catalana durant la “Renaixença”. El seu fundador, Thomas Reid, és conegut perquè va introduir una filosofia que no seguia l’escepticisme dels filòsofs citats. Sintetitzant, Hume va afirmar que l’experiència del sentit consisteix exclusivament en idees o impressions subjectives en la ment. Una resposta aquest “sistema ideal” va ser la filosofia del sentit comú que es va desenvolupar com a reacció a l’escepticisme de David Hume i altres filòsofs escocesos. Contra aquest “sistema ideal” la nova escola considera que l’experiència ordinària dels homes dona instintivament certes creences de la pròpia existència; de la existència dels objectes reals directament percebuts; i de “principis bàsics” basats en creences morals i religioses. Entre 1816 a 1870 la doctrina escocesa va ser adoptada com a filosofia oficial a França. Els seus principis van obtenir força a través de Víctor Cousin i de la traducció de les obres de Thomas Reid al francès per Jouffroy. Serà doncs, a partir de les traduccions franceses que Ramon Martí d’Eixalà va introduir a Catalunya la filosofia escocesa (no existeix cap prova que Martí d’Eixalà hagués conegut les versions angleses de les obres de Reid). En conclusió, el moviment escocès del sentit comú va influenciar l’escola catalana de filosofia.
Why Catalonia will see its energy metabolism increase in the near future: an application of MuSIASEM
Resumo:
This paper applies the so-called Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) to the economy of the Spanish region of Catalonia. By applying Georgescu-Roegen's fund-flow model, it arrives at the conclusion that within a context of the end of cheap oil, the current development model based on the growth of low productivity sectors such as services and construction must change. The change is needed not only because of the increasing scarcity of affordable energy carriers, or because of the increasing environmental impact that the present development represents, but also because of an ageing population that demands labour productivity gains. This will imply industry requiring more energy consumption per worker in order to increase its productivity, and therefore its competitiveness. Thus, we conclude that energy intensity, and exosomatic energy metabolism of Catalonia will increase dramatically in the near future unless major conservation efforts are implemented in both the household and transport sectors.
Resumo:
Els espais periurbans juguen un paper important en la configuració del territori i del medi ambient, ja que contenen valors i acullen funcions diverses (ecològiques i ambientals, socials i lúdiques, productives etc.). Si bé és cert que a la comarca del Vallès Occidental aquests espais són –també- producte de la relació amb un context geogràfic molt humanitzat, també ho és que actualment i en aquest context, es donen circumstàncies d’amenaça a l’equilibri que fou origen dels valors i funcions esmentats (tendències urbanitzadores i metropolització). Aquest escenari de complexitat demana una òptima ordenació del territori que garanteixi la preservació dels valors i funcions anomenats. El marc i les eines dels quals la societat s’ha dotat per a fer-ho les aporta el planejament del territori, la legislació sectorial etc. Tot i que aquest marc presenta oportunitats per a l'ordenació d’espais de sòl no urbanitzable periurbà, a la realitat pràctica s’observen pocs resultats d’aquesta favorable avinentesa. Aquesta és la paradoxa principal que planteja l’estudi de la temàtica escollida.
Resumo:
El Parc Natural de l’Alt Pirineu i l’Ajuntament de Valls de Valira van posar-se d’acord per rehabilitar i convertir les antigues escoles del poble d’Os de Civís en el futur CITF, el qual entrarà en funcionament l’any 2009. Aquest equipament cultural “es centrarà en l’estudi i difusió de les temàtiques relacionades amb el fet fronterer al llarg de la història, actualment i en el futur”, contribuint a fer comprendre el present amb perspectiva històrica en una zona on hi manquen aquests tipus d’equipament. És precisament aquí on es situa aquest projecte ja què serveix al PNAP com a eina pel desenvolupament del centre, i també s’ha d’utilitzar de guió, tan pel que fa al seu contingut expositiu com al disseny museològic en el futur projecte d’execució de l’equipament.
Resumo:
The present paper analyses the link between firms’ decisions to innovate and the barriers that prevent them from being innovative. The aim is twofold. First, it analyses three groups of barriers to innovation: the cost of innovation projects, lack of knowledge and market conditions. Second, it presents the main steps taken by Catalan Government to promote the creation of new firms and to reduce barriers to innovation. The data set used is based on the 2004 official innovation survey of Catalonia which was taken from the Spanish CIS-4 sample. This sample includes individual information on 2,954 Catalan firms in manufacturing industries and knowledge-intensive services (KIS). The empirical analysis reveals pronounced differences regarding a firm’s propensity to innovate and its perception of barriers. Moreover, the results show that cost and knowledge barriers seem to be the most important and that there are substantial sectoral differences in the way that firms react to barriers. The results of this paper have important implications for the design of future public policy to promote entrepreneurship and innovation together.
Resumo:
Proyecto de investigación realizado a partir de una estancia en Andorra entre mayo y agosto del 2007. Se ha consultado y vaciado varios tipos de documentación para complementar los trabajos históricos, arqueológicos y paleoambientales desarrollados en los valles de Madriu, Perafita i Claror (Andorra ). El vaciado ha aportado documentos que hacen referencia directa a los usos del suelo y el carácter administrativo del área de estudio.
Resumo:
Aquest es un estudi de la contribució d’un ramat mixt d’oví i cabrum a la gestió de les masses forestals per a la prevenció d’incendis al municipi de Matadepera. L’avaluació de l’acció del ramat s’ha efectuat mitjançant un estudi integrat a traves del coneixement local i l’estudi ecològic de les zones pasturades. La ramaderia extensiva i especialment els ramats d’ovelles i cabres han contribuït durant segles a la neteja del sotabosc mitjançant l’aprofitament productiu d’aquestes zones, per tant no es quelcom nou, sinó un reconeixement als serveis ecològics no productius de la ramaderia extensiva i com aquesta es eficaç en la prevenció d’incendis forestals.