1,137 research outputs found

    Internal Migration and Regional Population Dynamics in Europe: Portugal Case Study

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    Report prepared for the Council of Europe (Directorate of Social and Economic Affairs, Population and Migration Division) and for European Commission (Directorate General V, Employment, Industrial Relations and Social Affairs, Unit E1, Analysis and Research on the Social Situation). This paper reports on internal migration and regional population dynamics in Portugal. It examines internal migration patterns and trends in two years, 1981 and 1991, and compares them. Portugal is a country that has reached a population plateau and is currently experiencing very little overall population growth. In 1981 its population was 9.83 millions, only 9.87 millions in 1991 and 9.96 millions in 1997. During the 1980s natural increase steadily diminished and in the 1990s it has virtually ceased. International migration was predominantly negative in balance during the period between the mid 1980s and early 1990s, but has moved into small positive gains in the last few years. When population changes for the 1981-91 period are examined, the picture is broadly of gains in the major urban-centred regions of Norte and Lisboa Vale Tejo, and in the resort industry region of the Algarve. In the more peripheral regions, population decreases occurred, that is in the Centro, Alentejo and Açores regions with Madeira being roughly in balance. Natural increase was strong in the Norte and island regions and compensated for net out-migration, while elsewhere it was weak. All Portuguese NUTS 2 regions except the Algarve lost through migration, with emigration dominating any counter-flows due to internal migration. However, the strong influence of internal migration is apparent when the components of population change at concelhos scale are analysed. The largest cities, Lisboa and Porto, lose population in the 1981-91 period, particularly the capital, and part of the population losses represent migration to surrounding concelhos in the Outer parts of the city regions. Most of the rest of Grande Porto outside of the main city gains population through migration. Around Lisboa these suburban migration gains were experienced by the margins of Lisboa itself, the northern suburbs along the north bank of the Tagus and in a majority of the concelhos of Península Setúbal across the Tagus estuary from Lisboa, namely the southern suburbs linked to the city by two major road bridges. The Censuses of 1981 and 1991, which count migrants in the circa 15-month period before the census date (14½ and 15½ months in the two censuses), provide a picture of how internal migration affects people in different life stages. The all ages pattern of migration in 1979-81 is one of greatest losses from interior and eastern regions (NUTS 3 scale), lesser losses from remoter coastal regions and gains to the urban regions centred on Porto, Lisboa and the Algarve resorts. However, the centres of the Porto and Lisboa regions lose migrants, confirming the earlier interpretation of the components of population change. The situation in 1989-91 was similar but there were fewer regions with great migration losses, more regions with moderate losses and gains around the main urban nodes and the southern tourist coast. This general pattern of redistribution characterises the childhood and family ages (0-14, 25-44) and is intensified in terms of losses from the large cities and suburban gains in the 45-64 age group. Young persons, however, behave differently. In 1979-81 most of the regions of the country lost internal migrants in the 15-24 age group, while Lisboa, Porto and the Algarve experienced substantial migration gains. So, while the family ages showed a de-concentration pattern, the ages at which young adults start independent life careers showed centralising tendencies. The spatial pattern was broadly similar in 1989-91 but more interior regions posted migration gains. The retirement ages, 65 to 74, showed similar centralisation for the female population but not for the male. This age group was the only one that exhibited strong gender differences in the pattern of migration and considerable changes between 1979-81 and 1989-91. Whereas in the former period, the pattern was very much one of interior loss and coastal and urban region gain, in 1989-91, losses from the interior were relatively lower and moderate gains more widespread. At the oldest ages of 75 years or more the strong pattern of interior loss and coastal gain reasserted itself. Portuguese population dynamics thus exhibit some rural depopulation (mainly of the young and the very old), some urbanisation (migration to more densely settled regions around the biggest cities), some suburbanisation (de-concentration within the largest urban regions) and some regional flows to resource exploiting regions (sun and sea in the resort coast of the Algarve). Population gains in the 1981-91 decade also occurred in several coastal and interior small towns and medium-sized urban centres outside of Lisboa and Porto. This reveals that urbanisation was not just a metropolitan phenomenon but was a widespread process. Note that when considering whether the Portuguese population is centralising or decentralising, attention must be paid to the scale of migration observed. So, for example, population may be moving into the metropolitan regions of Lisboa and Porto and therefore centralising, but within those regions the population may be shifting from city to suburbs and to outer parts of the city region, and therefore decentralising. This nested system of flows may be obscured if attention is focused exclusively on total net migration

    Filtering the Tau method with Frobenius-Pad\'e Approximants

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    In this work, we use rational approximation to improve the accuracy of spectral solutions of differential equations. When working in the vicinity of solutions with singularities, spectral methods may fail their propagated spectral rate of convergence and even they may fail their convergence at all. We describe a Pad\'e approximation based method to improve the approximation in the Tau method solution of ordinary differential equations. This process is suitable to build rational approximations to solutions of differential problems when their exact solutions have singularities close to their domain

    Imaging 3D seismic velocity along the seismogenic zone of Algarve region (southern Portugal)

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    The present seismic tomographic study is focused around Algarve region, in South of Portugal. To locate the seismic events and find the local velocity structure of epicentral area, the P and S arrival times at 38 stations are used. The data used in this study were obtained during the Algarve campaign which worked from January/2006 to July/2007. The preliminary estimate of origin times and hypocentral coordinates are determined by the Hy- poinverse program. Linearized inversion procedure was applied to comprise the following two steps: 1) finding the minimum 1D velocity model using Velest and 2) simultaneous relocation of hypocenters and determination of local velocity structure. The velocity model we have reached is a 10 layer model which gave the lowest RMS, after several runnings of eight different velocity models that we used “a priori”. The model parameterization assumes a continuous velocity field between 4.5 km/s and 7.0 km/s until 30 km depth. The earth structure is represented in 3D by velocity at discrete points, and velocity at any intervening point is determined by linear interpolation among the surrounding eight grid points. A preliminary analysis of the resolution capabilities of the dataset, based on the Derivative Weight Sum (DWS) distribution, shows that the velocity structure is better resolved in the West part of the region between the surface to15 km. The resulting tomographic image has a prominent low-velocity anomaly that shows a maximum decrease in P-wave velocity in the first 12 kms in the studied region. We also identified the occurrence of local seismic events of reduced magnitude not catalogued, in the neighbourhood of Almodôvar (low Alentejo). The spatial distribution of epicentres defines a NE-SW direction that coincides with the strike of the mapped geological faults of the region and issued from photo-interpretation. Is still expectable to refine the seismicity of the region of Almodôvar and establish more rigorously its role in the seismotectonic picture of the region. This work is expected to produce a more detailed knowledge of the structure of the crust over the region of Algarve, being able to identify seismogenic zones, potentially generators of significant seismic events and also the identification of zones of active faults

    Endothelial Dysfunction in Type 2 Diabetes: Targeting Inflammation

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    Several experimental and clinical studies have indicated a prominent role of vascular inflammation in the development of endothelial dysfunction. In endothelial dysfunction, the endothelium loses its physiological features, decrements nitric oxide bioavailability, and shifts towards a vasoconstrictor, pro-thrombotic and pro-inflammatory state. Within arterial wall, the interplay between the pro-inflammatory and pro-oxidant milieus promotes vascular dysfunction, and perivascular adipose tissue seems to play an important role. Inflammation is now considered a key event in vascular dysfunction and the development of vascular disease associated with obesity and type 2 diabetes. This concept is supported by the fact that anti-inflammatory adipokines such as adiponectin protect endothelial function, and interventions resulting in reduced inflammation such as the administration of salicylates prevent vascular dysfunction and cardiovascular events. Thus, the aim of this review is to address the role of inflammation and its mechanisms in endothelial dysfunction associated with diabetes, describing the impact of these conditions on vascular function

    Solid-phase extraction of nitro-PAH from aquatic samples and its separation by reverse-phase capillary liquid chromatography

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    In this work, an analytical methodology to extract 1-nitronaphthalene, 2-nitrofluorene, 9-nitroanthracene, 3-nitrofluoranthene, and 1-nitropyrene aquatic samples is proposed. Capillary liquid chromatography with on-column UV detection (µLC-UV) was employed to separate and quantitate all five nitrated polycyclic aromatic hydrocarbons (nitro-PAH) extracted from water samples. Two different extraction techniques were tested and compared: liquid-liquid extraction (LLE) and solid phase extraction (SPE) with two different sorbents, octadecylsilica (C18) and styrene divinylbenzene (XAD-2) particles. The elution of analytes was tested with both acetonitrile and methylene chloride. The best recovery results were obtained for SPE-C18 extraction with the methylene chloride with values ranging from 76 to 97% with RSD values smaller than 4%. The chromatographic conditions for analysis was carried out using a 250 × 0.3 mm i.d. packed capillary column with 5 µm C18 particles. The elution was isocratic with 65% acetonitrile in water (v/v) as mobile phase with a flow rate of 7 µL min-1. The detection limits due to on-column UV detection (ranging ~3-30 mmol L-1) are limiting for environmental applications, however, they are suited for toxicological studies

    Long-term survival in a patient with brain metastases of papillary thyroid carcinoma

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    We present the case of a 43-year-old woman who underwent total thyroidectomy with bilateral lymphadenectomy for a papillary thyroid carcinoma (PTC), solid variant (T4bN1bMx), with V600E BRAF mutation. After ablative therapy, she presented undetectable thyroglobulin (Tg) but progressively increasing anti-Tg antibodies (TgAbs). During follow-up, nodal, lung and brain metastases were identified. She was submitted to surgical excision of lung lesions, radiosurgery of brain metastases and five radioiodine treatments. The latest brain MRI showed no lesions, pulmonary CT showed stable micronodules and there was progressive reduction in TgAbs. This is a peculiar case of a PTC with lung and brain metastatic lesions detected through TgAbs. Initial histological and molecular study suggested a more aggressive clinical behaviour, which was eventually confirmed. Although PTC brain metastases are extremely rare and present poor prognosis, our patient presented a good response to treatment and longer survival than usually reported for similar cases.info:eu-repo/semantics/publishedVersio

    Nomear objetos: uma questão de idade?

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    Poster apresentado no 2º Congresso Internacional de Saúde do Instituto Politécnico de Leiria, 9-10 Maio 2014, Leiria

    Carcinoma da Tiróide em Crianças e Jovens Adultos: Revisão Retrospectiva de 19 Casos

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    Introduction: Thyroid carcinoma is rare in children and young adults. Most of management guidelines are based in data from adult population. Several controversies remain regarding the aggressiveness of clinical presentation and therapeutic approach. Objective: To evaluate all differentiated thyroid carcinoma patients with less than 20 years-old at presentation reflecting the experience of our unit in relation to diagnosis, treatment and follow-up of this clinical entity. Material and Methods: This is a retrospective review of clinical records of all children and young adults followed at Oncology Consultation of Department of Endocrinology of Centro Hospitalar e Universitário de Coimbra between 1996 and 2012. Results: Nineteen patients with mean age of 16 years old were followed, 13 girls and 6 boys. None of the patients had previous neck irradiation. A palpable cervical mass was the presenting complaint in 84.6%. FNA was performed in 15 patients and was diagnostic or suspicious of malignancy in 71.4%. Total thyroidectomy was performed in 18 cases (94.7%). Papillary carcinoma was identified in all. Vascular invasion and multicentry occurred in 21.1%. Mean tumor size was 2.5cm. Cervical lymph node involvement was diagnosed in 31.6% and distant metastases in 5.2%. The majority of patients (18 in 19) were classified as stage I disease. All patients received thyroxine suppressive therapy and postoperative radioiodine ablation was given to 84.2% (mean dose 85.7mCi). During mean follow-up of almost 6 years, 16 patients remain disease free. Conclusion: In our series, cervical lymph node and distant metastases rates were similar to that found in adult population. Overall prognosis was very good
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