12 resultados para Dates de péremption


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New radiocarbon measurements were obtained from middle and upper Paleolithic sites currently under research by the CEPUNL, in well defined stratigraphical situations. With other dates, they yield an approximative chronological global view. Measurement distribution in function of time does not seem to be an hazardous one. In the actual status of our knowledge, this distribution seems to fit in some assemblages: (a) 14000 to 15000 BP, Solutrean; (b) about 20 000 BP, Solutrean; (c) circa 25 000 BP, already Solutrean, and slightly older than 26 000 BP, still Mousterian; (d) between 29 000 and 31 000 BP, Mousterian. The persistance of Mousterian much later than its acknowledged upper limit at about 34 000 BP (and hence the survival of its neanderthalian authors) is demonstrated. For the first time it has been possible to ascertain the upper time limit of the marine 5-8 metres raised beach (Tyrrhenian III) at Serra da Arrábida, and also the age of archaeological sites without stone artifacts, or with uncharacteristic ones. The obtained measurements allow US to correlate localities and sedimentary units with last glaciation events. There seems to have been a distinct correlation between cave and shelter human occupation and events marked by the worsening of climate.

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Onshore, the Piacenzianof the Mondego and Lower Tagus Tertiary basins comprises siliciclastic sediments deposited in shallow marine to continental environments. The outcrops of the deposits are relatively widespread in the Aveiro and Seuibal region. A lithostratigraphic synthesis based on the correlation of geological sections, is presented for the two basins. In general, the Piacenzian sediments display a regressive sucession. The Late Tortonian-Zanclean (?) confined drainage pattern changed at the beginning of Piazencian, to fluvial systems draining to the Atlantic, and capturing the drainage of the inner parts of the Hesperic Meseta. The Piacenzian sedimentary sequence post-dates one of the uprising phases during Neogene compression, recorded by a strong regional unconformity. Some local active faulting - as in Lousa, Rio Maior and Senibal- Pinhal Novo - allowed the local thickening of the sedimentary record. Later compressive tectonism continues to generate reverse faulting and diapiric reactivation, affecting those sediments. Currently, the Piacenzian deposits culminates the marginal piedmonts, widely eroded by the Quaternary fluvial dissection.

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Etnográfica, Vol. IX, N.1, pp. 171-193

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New radiocarbon measurements were obtained from middle and upper Paleolithic sites currendy under research by the CEPUNL, in well defined stratigraphical situations. With other dates, they yield an approximative chronological global view. Measurement dístribution in function of time does not seem to be an hazardous one. ln the actual status of our knowledge, this distribution seems to fit in some assemblages: (a) 14000 to 15000 BP, Solurrean ; (b) about 20 000 BP, Solurrean ; (e) area 25 000 BP, already Solurrean, and slightly older than 26 000 BP, still Mousterian ; (d) between 29 000 and 31 000 BP, Mousterian. The persistance of Mousterian much later than its acknowledged upper limit at about 34 000 BP (and hence the survival of its neanderthalian authors) is demonstrated. For the first time it has been possible to ascertain the upper time limit of the marine 5-8 metres raised beach (Tyrrhenian III) at Serra da Arrábida, and also the age of archaeological sires wirhout srone arrifacts, or with uncharacteristic ones. The obtained measurements allow us to correlate localities and sedimentary units with last glaciation events. There seems to have been a distinct correlation between cave and shelter human occupation and events marked by the worsening of climate.

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Onshore, the Piacenzian of the Mondego and Lower Tagus Tertiary basins comprises siliciclastic sediments deposited in shallow marine to continental environments. The outcrops of the deposits are relatively widespread in the Aveiro and Setúbal region. A lithostratigraphic synthesis based on the correlation of geological sections, is presented for the two basins. In general, the Piacenzian sediments display a regressive sucession. The Late Tortonian-Zanclean (?) confined drainage pattern changed at the beginning of Piazencian, to fluvial systems draining to the Atlantic, and capturing the drainage of the inner parts of the Hesperic Meseta. The Piacenzian sedimentary sequence post-dates one of the uprising phases during Neogene compression, recorded by a strong regional unconformity. Some local active faulting - as in Lousa, Rio Maior and Senibal- Pinhal Novo - allowed the local thickening of the sedimentary record. Later compressive tectonism continues to generate reverse faulting and diapiric reactivation, affecting those sediments. Currently, the Piacenzian deposits culminates the marginal piedmonts, widely eroded by the Quaternary fluvial dissection.

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Dissertação para obtenção do Grau de Mestre em Matemática e Aplicações Especialização em Actuariado, Estatística e Investigação Operacional

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ABSTRACT - The problem of how to support “intentions to make behavioural changes” (IBC) and “behaviour changes” (BC) in smoking cessation when there is a scarcity of resources is a pressing issue in public health terms. The present research focuses on the use of information and communications technologies and their role in smoking cessation. It is developed in Portugal after the ratification of WHO Framework Convention on Tobacco Control (on 8 November 2005). The prevalence of smokers over fifteen years of age within the population stood at 20.9% (30.9% for men and 11.8% for women). While the strategy of helping people to quit smoking has been emphasised at National Health Service (NHS) level, the uptake of cessation assistance has exceeded the capacity of the service. This induced the search of new theoretical and practical venues to offer alternative options to people willing to stop smoking. Among these, the National Health Plan (NHP) of Portugal (2004-2010), identifies the use of information technologies in smoking cessation. eHealth and the importance of health literacy as a means of empowering people to make behavioural changes is recurrently considered an option worth investigating. The overall objective of this research is to understand, in the Portuguese context, the use of the Internet to help people to stop smoking. Research questions consider factors that may contribute to “intentions to make behavioural changes” (IBC) and “behavioural changes” (BC) while using a Web-Assisted Tobacco Intervention Probe (WATIP). Also consideration is given to the trade-off on the use of the Web as a tool for smoking cessation: can it reach a vast number of people for a small cost (efficiency) demonstrating to work in the domain of smoking cessation (efficacy)”? In addition to the introduction, there is a second chapter in which the use of tobacco is discussed as a public health menace. The health gains achieved by stopping smoking and the means of quitting are also examined, as is the use of the Internet in smoking cessation. Then, several research issues are introduced. These include background theory and the theoretical framework for the Sense of Coherence. The research model is also discussed. A presentation of the methods, materials and of the Web-Assisted Tobacco Intervention Probe (WATIP) follows. In chapter four the results of the use of the Web-Assisted Tobacco Intervention Probe (WATIP) are presented. This study is divided into two sections. The first describes results related to quality control in relation to the Web-Assisted Tobacco Intervention Probe (WATIP) and gives an overview of its users. Of these, 3,150 answered initial eligibility questions. In the end, 1,463 met all eligibility requirements, completed intake, decided on a day to quit smoking (Dday) and declared their “intentions to make behavioural changes” (IBC) while a second targeted group of 650 did not decide on a Dday. With two quit attempts made before joining the platform, most of the participants had experienced past failures while wanting to stop. The smoking rate averaged 21 cigarettes per day. With a mean age of 35, of the participants 55% were males. Among several other considerations, gender and the Sense of Coherence (SOC) influenced the success of participants in their IBC and endeavour to set quit dates. The results of comparing males and females showed that, for current smokers, establishing a Dday was related to gender differences, not favouring males (OR=0.76, p<0.005). Belonging to higher Socio-economic strata (SES) was associated with the intention to consider IBC (when compared to lower SES condition) (OR=1.57, p<0.001) and higher number of school years (OR=0.70, p<0.005) favoured the decision to smoking cessation. Those who demonstrated higher confidence in their likelihood of success in stopping in the shortest time had a higher rate of setting a Dday (OR=0.51, p<0.001). There were differences between groups in IBC reflecting the high and low levels of the SOC score (OR=1.43, p=0.006), as those who considered setting a Dday had higher levels of SOC. After adjusting for all variables, stages of readiness to change and SOC were kept in the model. This is the first Arm of this research where the focus is a discussion of the system’s implications for the participants’ “intentions to make behavioural changes” (IBC). Moreover, a second section of this study (second Arm) offers input collected from 77 in-depth interviews with the Web-Assisted Tobacco Intervention Probe (WATIP) users. Here, “Behaviour Change” (BC) and the usability of the platform are explored a year after IBC was declared. A percentage of 32.9% of self-reported, 12-month quitters in continuous abstinence from smoking from Dday to the 12-month follow- up point of the use of the Web-Assisted Tobacco Intervention Probe (WATIP) has been assessed. Comparing the Sense of Coherence (SOC) scores of participants by their respective means, according to the two groups, there was a significant difference in these scores of non smokers (BC) (M=144,66, SD=22,52) and Sense of Coherence (SOC) of smokers (noBC) (M=131,51, SD=21,43) p=0.014. This WATIP strategy and its contents benefit from the strengthening of the smoker’s sense of coherence (SOC), so that the person’s progress towards a life without tobacco may be experienced as comprehensible, manageable and meaningful. In this sample the sense of coherence (SOC) effect is moderate although it is associated with the day to quit smoking (Dday). Some of the limitations of this research have to do with self-selection bias, sample size (power) and self-reporting (no biochemical validation). The enrolment of participants was therefore not representative of the smoking population. It is not possible to verify the Web-Assisted Tobacco Intervention Probe (WATIP) evaluation of external validity; consequently, the results obtained cannot be applied generalized. No participation bias is provided. Another limitation of this study is the associated limitations of interviews. Interviewees’ perception that fabricating answers could benefit them more than telling the simple truth in response to questions is a risk that is not evaluated (with no external validation like measuring participants’ carbon monoxide levels). What emerges in this analysis is the relevance of the process that leads to the establishment of the quit day (Dday) to stop using tobacco. In addition, technological issues, when tailoring is the focus, are key elements for scrutiny. The high number of dropouts of users of the web platform mandates future research that should concentrate on the matters of the user-centred design of portals. The focus on gains in health through patient-centred care needs more research, so that technology usability be considered within the context of best practices in smoking cessation.

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This paper develops a model of a forest owner operating in an open-city environment, where the rent for developed land is increasing concave in nearby preserved open space and is rising over time reflecting an upward trend in households’ income. Thus, our model creates the possibility of switching from forestry to residential use at some point in the future. In addition it allows the optimal harvest length to vary over time even if stumpage prices and regeneration costs remain constant. Within this framework we examine how adjacent preserved open space and alternative development constraints affect the private landowner´s decisions. We find that in the presence of rising income, preserved open space hastens regeneration and conversion cuts but leads to lower density development of nearby unzoned parcels due to indirect dynamic effects. We also find that both a binding development moratorium and a binding minimum-lot-size policy can postpone regeneration and conversion cut dates and thus help to protect open space even if only temporarily. However, the policies do not have the same effects on development density of converted forestland. While the former leads to high-density development, the latter encourages low-density development.

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This paper aims at building a theoretical framework to examine the impact of development pressure on private owner’s forest management practices, namely, on regeneration and conversion cut dates. As the rent for developed land is rising over time, our model creates the possibility of switching from forestry to residential use at some point in the future, thus departing from the Faustmann’s traditional setup. Comparative statics results with respect to stumpage prices, regeneration costs and urban growth parameters are provided. The results obtained depend on the impact on the opportunity cost of holding the stand and the impact on the opportunity cost of holding the land, generalizing Faustmann’s unambiguous results.

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O achado de um dente de mastodonte, cf. Tetralophodon longirostris, em depósitos marinhos expostos na praia de Penedo Norte, na Península de Setúbal, permitiu datação rigorosa. Provém da camada 8 do corte, parte basal da sequência deposicional T1; data do início do Tortoniano, ca. de 11.6 Ma, com base em foraminíferos planctónicos (zona N14) e em 87Sr/86Sr e K/Ar. O dente de mastodonte parece pertencer a Tetralophodon longirostris, espécie conhecida em Portugal em depósitos continentais da primeira parte do Miocénico superior.

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The oldest Portuguese share index still being calculated is the BVL/PSI-General, one which started the daily series on 5/Jan/1988 with a base value of 1000 points. Everyday a single value is computed based on the closing prices of all the shares included in the sample. Also, all corporate events affecting the price of any share beyond market sentiment are taken into account through proper adjustments, either in the numerator or the denominator of the formula. However, for dates before January 1988, there is nothing comparable to this index since the two different series known either never disclosed the methodology adopted to calculate the index or followed solutions not compatible with the above index. The present paper explains the solutions adopted to replicate as closely as possible the methodology of the BVL-General index to the main market of the Lisbon Exchange for the period 1978 – 1987. This is the first estimate of the historical Equity Risk Premium in Portugal above short-term risk-free rate from the re-opening of the market following the Carnation Revolution (and the accompanying nationalizations), to the present. In showing a value of the same order of magnitude found in other countries, the paper invites further studies on the effects of political decisions such as privatizations and joining the European Union.

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A Masters Thesis, presented as part of the requirements for the award of a Research Masters Degree in Economics from NOVA – School of Business and Economics