974 resultados para Recent Tectonic Evolution
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This paper studies a discrete dynamical system of interacting particles that evolve by interacting among them. The computational model is an abstraction of the natural world, and real systems can range from the huge cosmological scale down to the scale of biological cell, or even molecules. Different conditions for the system evolution are tested. The emerging patterns are analysed by means of fractal dimension and entropy measures. It is observed that the population of particles evolves towards geometrical objects with a fractal nature. Moreover, the time signature of the entropy can be interpreted at the light of complex dynamical systems.
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The evolution of the Lusitanian Basin, localized on the western Iberian margin, is closely associated with the first opening phases of the North Atlantic. It persisted from the Late Triassic to the Early Cretaceous, more precisely until the end of the Early Aptian, and its evolution was conditioned by inherited structures from the variscan basement. The part played by the faults that establish its boundaries, as regards the geometric and kinematic evolution and the organization of the sedimentary bodies, is discussed here, as well as with respect to important faults transversal to the Basin. A basin evolution model is proposed consisting of four rifting episodes which show: i) periods of symmetrical (horst and graben organization) and asymmetrical (half graben organization) geometric evolution; ii) diachronous fracturing; iii) rotation of the main extensional direction; iv) rooting in the variscan basement of the main faults of the basin (predominantly thick skinned style). The analysis and regional comparison, particularly with the Algarve Basin, of the time intervals represented by important basin scale hiatuses near to the renovation of the rifting episodes, have led to assume the occurrence of early tectonic inversions (Callovian–Oxfordian and Tithonian–Berriasian). The latter, however, had a subsequent evolution distinct from the first: there is no subsidence renovation, which is discussed here, and it is related to a magmatic event. Although the Lusitanian Basin is located on a rift margin which is considered non-volcanic, the three magmatic cycles as defined by many authors, particularly the second (approx. 130 to 110 My ?), performed a fundamental part in the mobilization of the Hettangian evaporites, resulting in the main diapiric events of the Lusitanian Basin. The manner and time in which the basin definitely ends its evolution (Early Aptian) is discussed here. Comparisons are established with other west Iberian margin basins and with Newfoundland basins. A model of oceanization of this area of the North Atlantic is also presented, consisting of two events separated by approximately 10 My, and of distinct areas separated by the Nazaré fault. The elaboration of this synthesis was based on: - information contained in previously published papers (1990 – 2000); - field-work carried out over the last years, the results of which have not yet been published; - information gathered from the reinterpretation of geological mapping and geophysical (seismic and well logs) elements, and from generic literature concerning the Mesozoic of the west iberian margin.
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This paper gives a short description of main stratigraphic unities from the early Cretaceous in Estremadura and Algarve, with their lithological, sedimentological and paleontological characteristics. The distribution of facies enable to propose a paleogeographic frame including eroded high areas and sedimentary low areas roughly parallel to the present coast. The early Cretaceous from Estremadura is splited up into three megasequences each one with regressive then transgressive tendencies: this fact must be connected with the leading action of distensive, slow or sudden, movements. Beyond the hercynian fault of Messejana, Algarve presents a different sedimentary evolution during the early Cretaceous.
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This paper is a summary of the results of the authors recent researches about the Western Iberian continental margin. During the Mesozoic, the margin is affected by two consecutive extensional phases interpreted as the result from two episodes of rifting in the Atlantic. Then during Cenozoic, subsidence was interrupted by compression and related deformation, specially during Eocene time. Ante-mesozoic basement controls the structural and sedimentary evolution of the margin.
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This paper presents a resume of the results achieved by researchers of the Centro de Estratigrafia e Paleobiologia da U. N. L. on the Neogene of Algarve, since 1977. The detailed study of several profiles as well as that af calcareous nannoplanton, planktonic foraminifera, ostracoda, fishes and mammals allowed to obtain data and correlation elements leading to a new interpretation of the Miocene of Algarve. It was possible to date and to characterize the following units: a) Carbonate formation of Lagos-Portimão, of marine facies, ascribed to the Lower Miocene (Aquitanian? and mainly Burdigalian), possibly attaining the Lower Langhian. b) Essentially arenaceous series of continental facies with a marine intercalation of Arrifão, Olhos de Água and Auramar Hotel beach, middle Miocene (Langhian-Serravallian) in age. c) Marine (tripoli, conglomerates, sands and limestones) deposits of Tunes-Mem Moniz, Ponte das Lavadeiras (Faro), Arroteia (Fuzeta) and Luz de Tavira, corresponding, at least partially, to the first part of the upper Miocene (Lower Tortonian). d) Cacela formation with three members: The lower member (conglomerates and sands), the middle (yellow silts) and the upper ones (gray silts), uppermost Tortonian and mainly Messinian in age. An interpretation of the tectonic and paleogeographic evolution of the portuguese littoral during the Miocene is also presented considering its insertion in the meridional part of the Peninsula (Guadalquivir depression, Betic massif basins and in the spanish Levant in general). Comparisons among the Neogene vulcanism of this region and similar manifestations documented in Algarve (basanite of Figueira-Portimão, etc) are established.
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XRD-analyses of pelitic deposits of Upper Jurassic to Miocene age occuring in the eastern Algarve (Portugal), give evidence of the occurrence of detrital clay minerals of continental origin as well as of conspicuous neoformations of marine provenance. The vertical succession of clay-mineral associations indicates the existence of three distinctive evolutionary cycles which are thought to reflect tectonically controlled transgressive-regressive events.
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The enzyme hydrogenase isolated from the sulphate reducing anaerobic bacterium Desulfovibrio gigas was encapsulated in reverse micelles of AOT–water–isooctane. The enzyme ability to consume molecular hydrogen was studied as a function of the micelle size (given by Wo = [H2O]/[organic solvent]). A peak of catalytic activity was obtained for Wo = 18, a micelle size theoretically fitting the heterodimeric hydrogenase molecule. At this Wo value, the recorded catalytic activity was slightly higher than in a buffer system(Kcat = 169.43 s−1 against the buffer value of 151 s−1). The optimal buffer used to encapsulate the enzyme was found to be imidazole 50 mM, pH 9.0. The molecular hydrogen production activity was also tested in this reverse micelle medium.
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OBJECTIVE To analyze Brazilian literature on body image and the theoretical and methodological advances that have been made. METHODS A detailed review was undertaken of the Brazilian literature on body image, selecting published articles, dissertations and theses from the SciELO, SCOPUS, LILACS and PubMed databases and the CAPES thesis database. Google Scholar was also used. There was no start date for the search, which used the following search terms: “body image” AND “Brazil” AND “scale(s)”; “body image” AND “Brazil” AND “questionnaire(s)”; “body image” AND “Brazil” AND “instrument(s)”; “body image” limited to Brazil and “body image”. RESULTS The majority of measures available were intended to be used in college students, with half of them evaluating satisfaction/dissatisfaction with the body. Females and adolescents of both sexes were the most studied population. There has been a significant increase in the number of available instruments. Nevertheless, numerous published studies have used non-validated instruments, with much confusion in the use of the appropriate terms (e.g., perception, dissatisfaction, distortion). CONCLUSIONS Much more is needed to understand body image within the Brazilian population, especially in terms of evaluating different age groups and diversifying the components/dimensions assessed. However, interest in this theme is increasing, and important steps have been taken in a short space of time.
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The career of prosthetics and orthotics in Portugal have a recent formative path: need to investigate the employability and employment of the graduates in Prosthetic and Orthotics (P&O) in ESTeSL between the academic years of 2004/05 and 2012/13; approaching to socio-demographic data and also academic and professional path. The questionnaire was applied to the P&O professional population graduated in ESTeSL. The results had been important to observe the future perspectives trends for the profession.
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OBJECTIVE To analyze the temporal evolution of maternal mortality and its spatial distribution.METHODS Ecological study with a sample made up of 845 maternal deaths in women between 10 and 49 years, registered from 1999 to 2008 in the state of Rio Grande do Sul, Southern Brazil. Data were obtained from Information System on Mortality of Ministry of Health. The maternal mortality ratio and the specific maternal mortality ratio were calculated from records, and analyzed by the Poisson regression model. In the spatial distribution, three maps of the state were built with the rates in the geographical macro-regions, in 1999, 2003, and 2008.RESULTS There was an increase of 2.0% in the period of ten years (95%CI 1.00;1.04; p = 0.01), with no significant change in the magnitude of the maternal mortality ratio. The Serra macro-region presented the highest maternal mortality ratio (1.15, 95%CI 1.08;1.21; p < 0.001). Most deaths in Rio Grande do Sul were of white women over 40 years, with a lower level of education. The time of delivery/abortion and postpartum are times of increased maternal risk, with a greater negative impact of direct causes such as hypertension and bleeding.CONCLUSIONS The lack of improvement in maternal mortality ratio indicates that public policies had no impact on women’s reproductive and maternal health. It is needed to qualify the attention to women’s health, especially in the prenatal period, seeking to identify and prevent risk factors, as a strategy of reducing maternal death.
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After a briefhistorical introduction, this paper deals with the main concerned geotectonic units: the Lower Tagus and Alvalade basins, the Western and Southern borders, and their infillings. Most of the Neogene events and record concern areas South of the Iberian Central Chain, a nearly inverse situation as that of Paleogene times. In the most important of these units, the Lower Tagus basin, there are quite thick detrital series, mostly marine in its distal part near Lisboa (albeit with several continental intercalations), and mainly continental in its inner part. Sedimentological record is almost complete since Lowermost to Upper Miocene. The richness ofdata (paleontology, isotope chronology, paleoclimate, etc.) it gives and the possibility of direct marine-continental correlations render this basin one of the more interesting ones in Western Europe. Alvalade basin is separated from the previous one by a barrier ofPaleozoic rocks. Two transgressions events (Upper Tortonian and Messinian in age) are recorded. Active sedimentation may be correlated to Late Miocene tectonics events. In Algarve, chiefly marine units from Lower to Upper Miocene are well developped. The Lower unit (Lagos-Portimao Formation) is best exposed in Western Algarve, but desappears eastwards. Middle Miocene is not as well known, whereas Upper Miocene main outcrops are in Eastern Algarve. Cacela Formation is remarquable for its beautiful fossils. Sedimentation as a whole refletcts the tectonic activity and in special the evolution of the Algarve flexures. There is scant evidence of post-Lower Miocene volcanism, the latest known in Portugal. Pliocene has not been recognized there beyond doubt. . Miocene sediments are much less important to the North of the Central Iberian Chain. Continental beds near Leiria that yielded the well-known "Hisp anotherium fauna" are lower Middle Miocene. Pliocene corresponds to dramatic changes in paleogeography. At Setiibal Peninsula there is some evidence of a minor Lower Pliocene transgression. Continental detrital sediments, often coarse, occupy rather large areas. In Western Portugal between the Seta hal Peninsula and Pombal there is good evidence of a marine Upper Pliocene transgression, followed up by dune sands overlain by marsh clays, diatomites, lignites and boghead levels that can be partly Pleistocene in age.
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The emergence of smartphones with Wireless LAN (WiFi) network interfaces brought new challenges to application developers. The expected increase of users connectivity will impact their expectations for example on the performance of background applications. Unfortunately, the number and breadth of the studies on the new patterns of user mobility and connectivity that result from the emergence of smartphones is still insufficient to support this claim. This paper contributes with preliminary results on a large scale study of the usage pattern of about 49000 devices and 31000 users who accessed at least one access point of the eduroam WiFi network on the campuses of the Lisbon Polytechnic Institute. Results confirm that the increasing number of smartphones resulted in significant changes to the pattern of use, with impact on the amount of traffic and users connection time.
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This survey intends to report some of the major documents and events in the area of fractional calculus that took place since 1974 up to the present date.
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Recent advances in vacuum sciences and applications are reviewed. Novel optical interferometer cavity devices enable pressure measurements with ppm accuracy. The innovative dynamic vacuum standard allows for pressure measurements with temporal resolution of 2 ms. Vacuum issues in the construction of huge ultra-high vacuum devices worldwide are reviewed. Recent advances in surface science and thin films include new phenomena observed in electron transport near solid surfaces as well as novel results on the properties of carbon nanomaterials. Precise techniques for surface and thin-film characterization have been applied in the conservation technology of cultural heritage objects and recent advances in the characterization of biointerfaces are presented. The combination of various vacuum and atmospheric-pressure techniques enables an insight into the complex phenomena of protein and other biomolecule conformations on solid surfaces. Studying these phenomena at solid-liquid interfaces is regarded as the main issue in the development of alternative techniques for drug delivery, tissue engineering and thus the development of innovative techniques for curing cancer and cardiovascular diseases. A review on recent advances in plasma medicine is presented as well as novel hypotheses on cell apoptosis upon treatment with gaseous plasma. Finally, recent advances in plasma nanoscience are illustrated with several examples and a roadmap for future activities is presented.
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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Electrotécnica e de Computadores