89 resultados para e-reserves


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From the late seventies to the present day, lacustrine sedimentology and lacustrine-related basin analysis have developed from a near-marginal aca- demic curiosity into a new ground-breaking multidisciplinary body of learning. The starting-point was economic interest in ancient lacustrine sequences as potential suppliers of natural resources such as raw materials (diatomites, clays), evaporite salts and energy (hydrocarbons and coal). The early discoveries of substantial hydrocarbon reserves connected with lacustrine facies in the western USA heralded the huge reserves found later in China, Brazil, western Africa, southeast Asia and the Caspian Sea, among other places.

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We annually monitored the abundance and size structure of herbivorous sea urchin populations (Paracentrotus lividus and Arbacia lixula) inside and outside a marine reserve in the Northwestern Mediterranean on two distinct habitats (boulders and vertical walls) over a period of 20 years, with the aim of analyzing changes at different temporal scales in relation to biotic and abiotic drivers. P. lividus exhibited significant variability in density over time on boulder bottoms but not on vertical walls, and temporal trends were not significantly different between the protection levels. Differences in densities were caused primarily by variance in recruitment, which was less pronounced inside the MPA and was correlated with adult density, indicating density-dependent recruitment under high predation pressure, as well as some positive feedback mechanisms that may facilitate higher urchin abundances despite higher predator abundance. Populations within the reserve were less variable in abundance and did not exhibit the hyper-abundances observed outside the reserve, suggesting that predation effects maybe more subtle than simply lowering the numbers of urchins in reserves. A. lixula densities were an order of magnitude lower than P. lividus densities and varied within sites and over time on boulder bottoms but did not differ between protection levels. In December 2008, an exceptionally violent storm reduced sea urchin densities drastically (by 50% to 80%) on boulder substrates, resulting in the lowest values observed over the entire study period, which remained at that level for at least two years (up to the present). Our results also showed great variability in the biological and physical processes acting at different temporal scales. This study highlights the need for appropriate temporal scales for studies to fully understand ecosystem functioning, the concepts of which are fundamental to successful conservation and management.

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The finding that tissue δ15N values increase with protein catabolism has led researchers to apply this value to gauge nutritive condition in vertebrates. However, its application to marine mammals has in most occasions failed. We investigated the relationship between δ15N values and the fattening/fasting cycle in a model species, the fin whale, a migratory capital breeder that experiences severe seasonal variation in body condition. We analyzed two tissues providing complementary insights: one with isotopic turnover (muscle) and one that keeps a permanent record of variations in isotopic values (baleen plates). In both tissues δ15N values increased with intensive feeding but decreased with fasting, thus contradicting the pattern previously anticipated. The apparent inconsistency during fasting is explained by the fact that a) individuals migrate between different isotopic isoscapes, b) starvation may not trigger significant negative nitrogen balance, and c) excretion drops and elimination of 15N-depleted urine is minimized. Conversely, when intensive feeding is resumed in the northern grounds, protein anabolism and excretion start again, triggering 15N enrichment. It can be concluded that in whales and other mammals that accrue massive depots of lipids as energetic reserves and which have limited access to drinking water, the δ15N value is not affected by fasting and therefore cannot be used as an indicatior of nutritive condition.

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This is the first TEM examination of vitellogenesis in the cestode Aporhynchus menezesi, a parasite of the velvet belly lanternshark Etmopterus spinax and a member of a little-studied trypanorhynch family, the Aporhynchidae. The synthetic activity of vitellocytes plays two important functions in the developmental biology of cestodes: (1) their shell-globules serve in eggshell formation; and (2) their accumulated reserves of glycogen and lipids represent a food source for the developing embryo. In A. menezesi, vitelline follicles consist of cells at various stages of development, from peripheral, immature cells of the gonial type to mature cells towards the centre of the follicle. These stages are: (I) immature; (II) early differentiation; (III) advanced maturation; and (IV) mature. Gradual changes involved in this process occur within each stage. Vitellogenesis involves: (1) an increase in cell volume; (2) the development of a smooth endoplasmic reticulum and an accelerated formation and accumulation of both unsaturated and saturated lipid droplets, along with their continuous enlargement and fusion; (3) the formation of individual β-glycogen particles and their accumulation in the form of glycogen islands scattered among lipid droplets in the cytoplasm of maturing and mature vitellocytes; (4) the rapid accumulation of large, moderately saturated lipid droplets accompanied by dense accumulations of β-glycogen along with proteinaceous shell-globules or shell-globule clusters in the peripheral layer during the advanced stage of maturation; (5) the development of cisternae of granular endoplasmic reticulum that produce dense, proteinaceous shell-globules; (6) the development of Golgi complexes engaged in the packaging of this material; and (7) the progressive and continuous enlargement of shell-globules into very large clusters in the peripheral layer during the advanced stage of maturation. Vitellogenesis in A. menezesi, only to some extent, resembles that previously described for four other trypanorhynchs. It differs in: (i) the reversed order of secretory activities in the differentiating vitellocytes, namely the accumulation of large lipid droplets accompanied by glycogenesis or β-glycogen formation during early differentiation (stage II), i.e. before the secretory activity, which is predominantly protein synthesis for shell-globule formation (stage III); (ii) the very heavy accumulation of large lipid droplets during the final stage of cytodifferentiation (stage IV); and (iii) the small number of β-glycogen particles present in mature vitellocytes. Ultracytochemical staining with PA-TCH-SP for glycogen proved positive for a small number of β-glycogen particles in differentiating and mature vitellocytes. Hypotheses, concerning the interrelationships of patterns of vitellogenesis, possible modes of egg formation, embryonic development and life-cycles, are commented upon.

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This is the first TEM examination of vitellogenesis in the cestode Aporhynchus menezesi, a parasite of the velvet belly lanternshark Etmopterus spinax and a member of a little-studied trypanorhynch family, the Aporhynchidae. The synthetic activity of vitellocytes plays two important functions in the developmental biology of cestodes: (1) their shell-globules serve in eggshell formation; and (2) their accumulated reserves of glycogen and lipids represent a food source for the developing embryo. In A. menezesi, vitelline follicles consist of cells at various stages of development, from peripheral, immature cells of the gonial type to mature cells towards the centre of the follicle. These stages are: (I) immature; (II) early differentiation; (III) advanced maturation; and (IV) mature. Gradual changes involved in this process occur within each stage. Vitellogenesis involves: (1) an increase in cell volume; (2) the development of a smooth endoplasmic reticulum and an accelerated formation and accumulation of both unsaturated and saturated lipid droplets, along with their continuous enlargement and fusion; (3) the formation of individual β-glycogen particles and their accumulation in the form of glycogen islands scattered among lipid droplets in the cytoplasm of maturing and mature vitellocytes; (4) the rapid accumulation of large, moderately saturated lipid droplets accompanied by dense accumulations of β-glycogen along with proteinaceous shell-globules or shell-globule clusters in the peripheral layer during the advanced stage of maturation; (5) the development of cisternae of granular endoplasmic reticulum that produce dense, proteinaceous shell-globules; (6) the development of Golgi complexes engaged in the packaging of this material; and (7) the progressive and continuous enlargement of shell-globules into very large clusters in the peripheral layer during the advanced stage of maturation. Vitellogenesis in A. menezesi, only to some extent, resembles that previously described for four other trypanorhynchs. It differs in: (i) the reversed order of secretory activities in the differentiating vitellocytes, namely the accumulation of large lipid droplets accompanied by glycogenesis or β-glycogen formation during early differentiation (stage II), i.e. before the secretory activity, which is predominantly protein synthesis for shell-globule formation (stage III); (ii) the very heavy accumulation of large lipid droplets during the final stage of cytodifferentiation (stage IV); and (iii) the small number of β-glycogen particles present in mature vitellocytes. Ultracytochemical staining with PA-TCH-SP for glycogen proved positive for a small number of β-glycogen particles in differentiating and mature vitellocytes. Hypotheses, concerning the interrelationships of patterns of vitellogenesis, possible modes of egg formation, embryonic development and life-cycles, are commented upon.

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El present estudi pretén posar en valor part del paper de l’Home del Programa MaB (Men and Biosphere). En concret, pretén descobrir la importància i el paper que pot tenir (o que té realment) l’anomenat patrimoni cultural per a la consecució dels objectius de la Reserva de la Biosfera, i les pròpies potencialitats que ofereix aquest patrimoni per al consum del turisme cultural

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Els traços primigenis del dibuix preparatori del Frontal de Sant Llorenç de Morunys, al Museu Diocesà i Comarcal de Solsona, s"observen a ull nu, sense haver d"emprar tècniques sofisticades, a causa d"una pèrdua important de l"estrat pictòric que, de conservar-se, impediria la lectura de les capes més profundes. S"han examinat aquestes traces, font de documentació privilegiada que se"ns ofereix per incrementar el coneixement de l"obra i també, per comprendre el procés d"elaboració d"una pintura sobre taula en el context del bisbat d"Urgell al tombant del segle XIII. Durant l"estudi ha estat possible reconstruir, amb el suport inestimable dels tractats medievals, la seqüència d"execució del dibuix preliminar: primer, la distribució provisional de les línies mestres a mà alçada, amb carbonet, seguit de la seva fixació amb una punta metàl·lica dura; segon, el traçat de l"esbós figuratiu, amb un estil tou, i el posterior repàs definitiu amb una agulla o punta afilada sobre l"estrat preparatori, creant un dibuix incís que romandria visible després de recobrir tota la superfície amb una làmina d"estany. Finalment, s"aplicaria una complexa policromia, que combinaria tècniques opaques i vernissos translúcids. La revisió d"un corpus d"obres catalanes de característiques similars, moltes en les reserves dels museus pel seu precari estat de conservació, podria aportar dades rellevants quant a les diferents tècniques del dibuix preparatori emprades en la pintura sobre taula d"època medieval.

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Desarrollo de una aplicación Android de alquiler de coches. Utiliza el servicio web de la empresa Canarias.com para consultar disponibilidad de vehículos y confirmar las reservas. Permite visualizar los detalles de vehículos y de los puntos de reserva, así como la localización de los puntos de reservas en el mapa.

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L’aplicació GSAI et permet gestionar els diferents espais que existeixen a la teva empresa. Et dona la capacitat de crear els teus espais personalitzats. Aquests espais s’agrupen per entitats així pots diferenciar cada zona de la teva empresa. Cada usuari pot crear reserves dins d’un espai i esborrar-la si es necessari.

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The referendum is a poorly used mechanism for direct participation in the Spanish system, at both state and regional level. The discussion on the feasibility of this system at regional level has been examined by the Constitutional Court. Influenced by the reluctance with which constituents viewed the mechanisms of direct democracy, they still have a reductive view of the referendum. The State therefore reserves the right to exercise very intensive controls on the provision and authorization of referendums and on the specific exercise of each referendum

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S'analitzen diversos caràcters morfomètrics i índexs relacionats amb la reproducció d'una mostra de 260 exemplars de Scorpaena notata. La proporció de mascles és molt més elevada que la de femelles, especialment a les talles més grosses. Les variacions estacionals de l'índex gonadosomitic (IGS) indiquen que aquesta espècie es reprodueix a l'estiu i principi de tardor, hipòtesi confirmada per l'estat de maduració de lesgònades observades. Així mateix, la disminució brusca que pateix l'index hepatosomàtic (MS) a la tardor posa de manifest que les reserves hepàtiques han estat utilitzades per a la posta

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En la societat en què vivim cada vegada agafen més importància les pàgines web, ja que és una eina d’informació molt útil i ràpida de consultar. Per això, no s’entén que una activitat empresarial sigui del tipus que sigui, no tingui representació a la xarxa. No és necessari que l’activitat en qüestió hagi de vendre productes a través d’Internet, sinó que simplement aquesta representació pot ajudar a donar a conèixer l’empresa i a ampliar la cartera de clients. De la mateixa manera, els dispositius mòbils també s’estan convertint en una eina important en la societat d’avui en dia i una bona aplicació pot aportar-te un avantatge en moltes de les feines diàries de les persones. D’aquestes idees sorgeix el projecte de fer la web i l’aplicació pel centre de fisioteràpia Fisioripoll. La web serviria per tenir un lloc a la xarxa on donar-se a conèixer i poder captar nous clients, i l’aplicació funcionaria com a eina pel propi centre, seria una espècie d’agenda electrònica per saber les hores que tens reservades els pròxims dies. Per aconseguir un bon funcionament de la web, s’ha demanat que la pàgina sigui administrable en els seus continguts. És a dir, que els propis gestors del centre puguin canviar els texts, les imatges dels diferents apartats i gestionar les reserves dels clients. En canvi, l’aplicació serà només una eina de consulta i no s’hauria de gestionar res. Per tal de dur a terme aquesta web s’ha tingut en compte utilitzar eines de programació de distribució lliure com és el llenguatge PHP, la base de dades MySQL, jQuery, el framework Phonegap per tal de poder construir una web i una aplicació amb cost de programari nul.

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The reproductive and general health of exploited fish stocks is an essential element of sustainable and profitable fisheries. The main purpose of this study was to assess the relationships between reproduction and two important parameters of fish health (parasitism and energy reserves) in female specimens of red mullet, Mullus barbatus, from the western Mediterranean Sea. We present new data for this species on (i) the prevalence and intensity of infection by metazoan parasites; (ii) the total lipid content in muscle and gonads as a measure of condition and (iii) fecundity and egg quality as a measure of their reproductive capacity. The results show that M. barbatus is a batch spawner with an income breeding strategy, an asynchronous development of oocytes and indeterminate fecundity. The results also indicate that the three most abundant and prevalent parasites significantly affect the condition and reproduction of M. barbatus. Specifically, the digenean, Opecoeloides furcatus, causes a reduction in the female"s energy reserves, while the nematodes, Hysterothylacium fabri and H. aduncum, produce a rise in egg production but impair egg quality. These implications of the relationships between parasitism, fish health and fish reproduction should be taken into consideration in the assessment and management of exploited species

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Understanding the factors controlling fine root respiration (FRR) at different temporal scales will help to improve our knowledge about the spatial and temporal variability of soil respiration (SR) and to improve future predictions of CO2 effluxes to the atmosphere. Here we present a comparative study of how FRR respond to variability in soil temperature and moisture in two widely spread species, Scots pines (Pinus sylvestris L.) and Holm-oaks (HO; Quercus ilex L.). Those two species show contrasting water use strategies during the extreme summer-drought conditions that characterize the Mediterranean climate. The study was carried out on a mixed Mediterranean forest where Scots pines affected by drought induced die-back are slowly being replaced by the more drought resistant HO. FRR was measured in spring and early fall 2013 in excised roots freshly removed from the soil and collected under HO and under Scots pines at three different health stages: dead (D), defoliated (DP) and non-defoliated (NDP). Variations in soil temperature, soil water content and daily mean assimilation per tree were also recorded to evaluate FRR sensibility to abiotic and biotic environmental variations. Our results show that values of FRR were substantially lower under HO (1.26 ± 0.16 microgram CO2 /groot·min) than under living pines (1.89 ± 0.19 microgram CO2 /groot·min) which disagrees with the similar rates of soil respiration previously observed under both canopies and suggest that FRR contribution to total SR varies under different tree species. The similarity of FRR rates under HO and DP furthermore confirms other previous studies suggesting a recent Holm-oak root colonization of the gaps under dead trees. A linear mixed effect model approach indicated that seasonal variations in FRR were best explained by soil temperature (p<0.05) while soil moisture was not exerting any direct control over FRR, despite the low soil moisture values during the summer sampling. Plant assimilation rates were positively related to FRR explaining part of the observed variability (p<0.01). However the positive relations of FRR with plant assimilation occurred mainly during spring, when both soil moisture and plant assimilation rates were higher. Our results finally suggest that plants might be able to maintain relatively high rates of FRR during the sub-optimal abiotic and biotic summer conditions probably thanks to their capacity to re-mobilize carbon reserves and their capacity to passively move water from moister layers to upper layers with lower water potentials (where the FR were collected) by hydraulic lift.