913 resultados para Tordera River (Catalonia)
Resumo:
Hydrogeological research usually includes some statistical studies devised to elucidate mean background state, characterise relationships among different hydrochemical parameters, and show the influence of human activities. These goals are achieved either by means of a statistical approach or by mixing modelsbetween end-members. Compositional data analysis has proved to be effective with the first approach, but there is no commonly accepted solution to the end-member problem in a compositional framework.We present here a possible solution based on factor analysis of compositions illustrated with a case study.We find two factors on the compositional bi-plot fitting two non-centered orthogonal axes to the most representative variables. Each one of these axes defines a subcomposition, grouping those variables thatlay nearest to it. With each subcomposition a log-contrast is computed and rewritten as an equilibrium equation. These two factors can be interpreted as the isometric log-ratio coordinates (ilr) of three hiddencomponents, that can be plotted in a ternary diagram. These hidden components might be interpreted as end-members.We have analysed 14 molarities in 31 sampling stations all along the Llobregat River and its tributaries, with a monthly measure during two years. We have obtained a bi-plot with a 57% of explained totalvariance, from which we have extracted two factors: factor G, reflecting geological background enhanced by potash mining; and factor A, essentially controlled by urban and/or farming wastewater. Graphicalrepresentation of these two factors allows us to identify three extreme samples, corresponding to pristine waters, potash mining influence and urban sewage influence. To confirm this, we have available analysisof diffused and widespread point sources identified in the area: springs, potash mining lixiviates, sewage, and fertilisers. Each one of these sources shows a clear link with one of the extreme samples, exceptfertilisers due to the heterogeneity of their composition.This approach is a useful tool to distinguish end-members, and characterise them, an issue generally difficult to solve. It is worth note that the end-member composition cannot be fully estimated but only characterised through log-ratio relationships among components. Moreover, the influence of each endmember in a given sample must be evaluated in relative terms of the other samples. These limitations areintrinsic to the relative nature of compositional data
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Drawing on data from two successive cohorts of PhD graduates, this paper analyses differences in overall job satisfaction and specific job domain satisfaction among PhDs employed in different sectors four years after completing their doctorate degrees. Covariate-adjusted job satisfaction differentials suggest that, compared to faculty members, PhD holders employed outside traditional academic and research jobs are more satisfied with the pecuniary facets of their work (principally, because of higher earnings), but significantly less satisfied with the content of their job and with how well the job matches their skills (and, in the case of public sector workers, with their prospects of promotion). The evidence regarding the overall job satisfaction of the PhD holders indicates that working in the public or private sectors is associated with less work well-being, which cannot be fully compensated by the better pecuniary facets of the job. It also appears that being employed in academia or in research centres provides almost the same perceived degree of satisfaction with the job and with its four specific domains. We also take into account the endogenous sorting of PhD holders into different occupations based on latent personal traits that might be related to job satisfaction. The selectivity-corrected job satisfaction differentials reveal the importance of self-selection based on unobservable traits, and confirm the existence of a certain penalisation for working in occupations other than academia or research, which is especially marked in the case of satisfaction with job content and job-skills match. The paper presents additional interesting evidence about the determinants of occupational choice among PhD holders, highlighting the relevance of certain academic attributes (especially PhD funding and pre-and-post-doc research mobility) in affecting the likelihood of being employed in academia, in a research centre or in other public or private sector job four years after completing their doctorate programme.
Resumo:
Objectives: To measure the health-related quality of life (HRQoL) of multiple sclerosis (MS) patients and their caregivers, and to assess which factors can best describe HRQoL. Methods: A cross-sectional multicenter study of nine hospitals enrolled MS patients and their caregivers who attended outpatient clinics consecutively. The instruments used were the SF-36 for patients and the SF-12 and GHQ-12 for caregivers. Classification and regression tree analysis was used to analyze the explanatory factors of HRQoL. Results: A total of 705 patients (mean age 40.4 years, median Expanded Disability Status Scale 2.5, 77.8% with relapsing-remitting MS) and 551 caregivers (mean age 45.4 years) participated in the study. MS patients had significantly lower HRQoL than in the general population (physical SF-36: 39.9; 95% confidence interval [CI]: 39.1–40.6; mental SF-36: 44.4; 95% CI: 43.5–45.3). Caregivers also presented lower HRQoL than general population, especially in its mental domain (mental SF-12: 46.4; 95% CI: 45.5–47.3). Moreover, according to GHQ-12, 27% of caregivers presented probable psychological distress. Disability and co-morbidity in patients, and co-morbidity and employment status in caregivers, were the most important explanatory factors of their HRQoL. Conclusions: Not only the HRQoL of patients with MS, but also that of their caregivers, is indeed notably affected. Caregivers’ HRQoL is close to population of chronic illness even that the patients sample has a mild clinical severity and that caregiving role is a usual task in the study context
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In the Cape Caribou River allochthon (CCRA), metaigneous and gneissic units occur as a shallowly plunging synform in the hanging wall of the Grand Lake thrust system (GLTS), a Grenvillian structure that forms the boundary between the Mealy Mountains and Groswater Bay terranes. The layered rocks of the CCRA are cut by a stockwork of monzonite dykes related to the Dome Mountain suite and by metadiabase-amphibolite dykes that probably form part of the ca. 1380 Ma Mealy swarm. The mafic dykes appear to postdate much of the development of subhorizontal metamorphic layering within the lower parts of the CCRA. The uppermost (least metamorphosed) units of the CCRA, the North West River anorthosite-metagabbro and the Dome Mountain monzonite suite, have been dated at 1625 +/- 6 and 1626 +/- 2 Ma, respectively. An amphibolite unit that concordantly underlies the anorthosite-metagabbro and is intruded discordantly by monzonite dykes has given metamorphic ages of 1660 +/- 3 and 1631 +/- 2 Ma. Granitoid gneisses that form the lowest level of the CCRA have given a migmatization age of 1622 +/- 6 Ma. The effects of Grenvillian metamorphism become apparent in the lower levels of the allochthon where gneisses, amphibolite, and mafic dykes have given new generation zircon ages of 1008 +/- 2, 1012 +/- 3, and 1011 +/- 3 Ma, respectively. A posttectonic pegmatite has also given zircon and monazite ages of 1016(-3)(+7) and 1013 +/- 3 Ma, respectively. Although these results indicate new growth of Grenvillian zircon, this process was generally not accompanied by penetrative deformation or melting. Thus, the formation of gneissic fabrics and the overall layered nature of the lower CCRA are a result primarily of Labradorian (1660-1620 Ma) tectonism and intrusion, and probably reflect early movement on an ancestral GLTS. Grenvillian heating and metamorphism (up to granulite facies) was strongly concentrated towards the base of the CCRA and probably occurred during northwestward thrusting of the allochthon over the Groswater Bay terrane.
Resumo:
To perform a climatic analysis of the annual UV index (UVI) variations in Catalonia, Spain (northeast of the Iberian Peninsula), a new simple parameterization scheme is presented based on a multilayer radiative transfer model. The parameterization performs fast UVI calculations for a wide range of cloudless and snow-free situations and can be applied anywhere. The following parameters are considered: solar zenith angle, total ozone column, altitude, aerosol optical depth, and single-scattering albedo. A sensitivity analysis is presented to justify this choice with special attention to aerosol information. Comparisons with the base model show good agreement, most of all for the most common cases, giving an absolute error within 0.2 in the UVI for a wide range of cases considered. Two tests are done to show the performance of the parameterization against UVI measurements. One uses data from a high-quality spectroradiometer from Lauder, New Zealand [45.04°S, 169.684°E, 370 m above mean sea level (MSL)], where there is a low presence of aerosols. The other uses data from a Robertson–Berger-type meter from Girona, Spain (41.97°N, 2.82°E, 100 m MSL), where there is more aerosol load and where it has been possible to study the effect of aerosol information on the model versus measurement comparison. The parameterization is applied to a climatic analysis of the annual UVI variation in Catalonia, showing the contributions of solar zenith angle, ozone, and aerosols. High-resolution seasonal maps of typical UV index values in Catalonia are presented
Resumo:
Les obres d’acondicionament i millora del riu Güell passen per dues fases. La primera, fins al 1971, demostren que el problema no estava ni de bon tros solucionat, més fruit de la improvisació i poca lògica de l’Administració que d'una bona política de planificació hidràulica. Les obres mes recents, (transvasament Güell-Marroc.Massanas-Ter), aparentment solucionen el problema. Però cal insistir un cop més; d'ençà el 1970 i fins avui dia, el riu Güell no ha sofert cap més avinguda important, si bé és cert que Girona no n'ha patit cap d’aquelles dimensions. Com passa en la majoria dels casos, el risc d'avingudes és un fantasma que ve de la mateixa manera que se'n va, que dura l’escàs període de l'avinguda i els dies-mesos que segueixen
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Estudi de la connectivitat fluvial del riu Fluvià en relació a l’anguila europea (Anguilla anguilla). S’identifiquen les barreres físiques transversals del curs principal d’aquest riu, es valora la connectivitat longitudinal mitjançant l’índex de connectivitat fluvial (ICF) i es proposen mesures correctores per tal de millorar la migració de l’anguila i el moviment natural d’altres espècies
Resumo:
Estudi de la distribució del pteridòfit invasor Azolla filiculoides al tram mitjà-baix del riu Ter, entre El Pasteral i la seva desembocadura, anàlisi dels factors ambientals que afecten el seu creixement i descripció del cicle biològic. Es proposen diverses pautes per a la seva gestió
Resumo:
L’anguila en els darrers 50 anys ha patit un fort declivi, es consideren diversos factors que han fet disminuir la seva població. Aquests factors són: la pesca, els obstacles, centrals hidroelèctriques, pèrdua d’hàbitat, depredació, paràsits i malalties, canvi climàtic i de corrents oceàniques. Aquesta espècie està definida per la UICN a la “llista vermella” d’espècies en perill d’extinció amb la categoria de “críticament amenaçada”. És per això que el Consell Europeu obliga a cada Estat membre que té pesqueries d’anguila a les seves conques a realitzar un PGA, que alhora, obliga a realitzar unes mesures de gestió. Una d’aquestes mesures, és la repoblació (def. Tornar a poblar un lloc amb anguiles, en aquest cas). En aquest projecte s’ha analitzat l’estat de les conques internes de Catalunya, realitzant una descripció pel que fa a l’àrea d’estudi i els impactes que s’hi poden trobar. Seguidament, mitjançant l’estudi de índex de qualitat i paràmetres ambientals, s’han indicat els trams òptims pel repoblament on pot sobreviure l’anguila degut a les condicions d’hàbitat. S’ha realitzat també un estudi comparatiu de densitats arreu de la comunitat de Catalunya, i un anàlisi de l’estat de la població d’anguila provinent del Llémena, observant al laboratori el seu estat sanitari. L’exportació d’anguila japonesa que s’ha realitzat en els darrers anys ha implantat un paràsit (A. Crassus) que li pot arribar a causar la mort
Resumo:
Aquest projecte pretén desenvolupar una proposta d’índexs ambientals per a l’avaluació de l’estat ecològic de la riera de l’Aubi; avaluar l’estat ambiental, classificar els diferents trams, identificar els punts crítics i definir les propostes de millora ambiental per a la riera d’Aubi. La riera de l’ Aubi es troba entre els termes municipals de Mont-ras, Palafrugell i Palamós, a les comarques del Baix Empordà i Gironès
Resumo:
Diagnosi de l’estat actual del riu Onyar per tal de proposar unes directrius orientatives que permetin aconseguir el bon estat ecològic del medi fluvial. Aquestes propostes es presenten en format de fitxes segons els trams principals on cal actuar i les actuacions més concretes per a cada un d’ells
Resumo:
Extensional detachment systems separate hot footwalls from cool hanging walls, but the degree to which this thermal gradient is the product of ductile or brittle deformation or a preserved original transient geotherm is unclear. Oxygen isotope thermometry using recrystallized quartz-muscovite pairs indicates a smooth thermal gradient (140 degrees C/100 m) across the gently dipping, quartzite-dominated detachment zone that bounds the Raft River core complex in northwest Utah (United States). Hydrogen isotope values of muscovite (delta D-Ms similar to-100 parts per thousand) and fluid inclusions in quartz (delta D-Fluid similar to-85 parts per thousand) indicate the presence of meteoric fluids during detachment dynamics. Recrystallized grain-shape fabrics and quartz c-axis fabric patterns reveal a large component of coaxial strain (pure shear), consistent with thinning of the detachment section. Therefore, the high thermal gradient preserved in the Raft River detachment reflects the transient geotherm that developed owing to shearing, thinning, and the potentially prominent role of convective flow of surface fluids.
Resumo:
Estudi de les plantes ornamentals conreades al sector esquerra de les ribes del Ter al seu pas per Girona, incidint en les espècies no autòctones i elaboració d’una cartografia digital dels arbres i arbusts de la zona de Sant Ponç (Girona)