Browsing by Issue Date, starting with "2019-11"
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- Da produção como totalidadePublication . Totta, SaraPretendemos analisar a abordagem materialista da categoria de totalidade desenvolvida por Marx, nomeadamente a sua aplicação teórica na interpretação dialéctica do conceito de produção no sistema económico capitalista.
- All for One: The Role of Colony Morphology in Bryophyte Desiccation TolerancePublication . Cruz De Carvalho, Ricardo; Maurício, António; Pereira, Manuel Franscisco; Marques da Silva, Jorge; Branquinho, CristinaIn the last decade, several works showed that even bryophytes from aquatic environments, if slowly dehydrated, can cope with desiccation in a response like the one from desert bryophytes. This led to the hypothesis that, if bryophytes from contrasting habitats can have similar responses, desiccation tolerance (DT) is partially inductive and not only constitutive as previously proposed and, therefore, colony morphology might be the key trait responsible for controlling dehydration rate essential for DT induction. Morphology and life form may be determinant traits in the adaptation of bryophytes to habitats with different water availabilities and corresponding predicted levels in the DT inducibility spectrum. Bryophytes from habitats with different water availabilities were dried as individual shoots and as a colony. The bryophyte Fontinalis antipyretica is fully aquatic presenting a streamer life form, while the three terrestrial species present turf life form with different sizes and degrees of space between individuals in the colony. Two species were collected under trees with moist soil presenting short turf (Tortella tortuosa) and long turf (Campylopus pyriformis) life forms. Another species was completely exposed to sun light with no surrounding trees and a tall turf life form (Pleurochaete squarrosa). We used chlorophyll a fluorescence parameter Fv/Fm (maximum potential quantum efficiency of Photosystem II) as a proxy to photosynthetic fitness throughout the contrasting dehydration rates (fast and slow). These bryophytes with different life forms were submitted to an X-ray computed microtomography (µ-XCT) to assess the three-dimensional inner structure and visualize locations for water storage. Shoots dried slow or fast according to the dehydration they were exposed to, as expected, but they presented similar dehydration rates across different species. However, the aquatic moss F. antipyretica, was unable to recover from fast drying, and after 24 h the recovery following slow drying was lower than the other species. The other three species presented full recovery after 24 h, either at the individual or colony level, and either from slow or fast drying. The only exception was the colonies of Campylopus pyriformis following fast drying that presented a slightly lower recovery, probably due to a looser colony structure.
- Characterization of the acoustic community of vocal fishes in the AzoresPublication . Carriço, Rita; Silva, Mónica A.; Meneses, Gui M.; Fonseca, Paulo; Amorim, Maria Clara P.Sounds produced by teleost fishes are an important component of marine soundscapes, making passive acoustic monitoring (PAM) an effective way to map the presence of vocal fishes with a minimal impact on ecosystems. Based on a literature review, we list the known soniferous fish species occurring in Azorean waters and compile their sounds. We also describe new fish sounds recorded in Azores seamounts. From the literature, we identified 20 vocal fish species present in Azores. We analysed long-term acoustic recordings carried out since 2008 in Condor and Princesa Alice seamounts and describe 20 new putative fish sound sequences. Although we propose candidates as the source of some vocalizations, this study puts into evidence the myriad of fish sounds lacking species identification. In addition to identifying new sound sequences, we provide the first marine fish sound library for Azores. Our acoustic library will allow to monitor soniferous fish species for conservation and management purposes.
- Monetary aggregates and macroeconomic performance : the Portuguese Escudo, 1911-1999Publication . Jalles, João TovarThis paper takes a long time span approach to provide a full characterization of several monetary aggregates over Portuguese’s historical economic business cycles. By focusing on the 1911-1999 period (the life span of the currency Escudo), the paper also revisits the issue of the role of money on real macroeconomic outcomes. We get inspiration from the monetarists versus Keynesians debate about direction of causality in the output-money relation and the quest for validity of money (non-)neutrality. By means of descriptive statistics we first uncover that money changes were associated with changes in real economic activity. Most monetary aggregates are more volatile than GDP, display high serial autocorrelation, are generally countercyclical and lead the economic cycle (except checking accounts). Then, through formal time series techniques, our results show that our monetary series were characterized by unit roots and were cointegrated with real GDP (after accounting for endogenously estimated breaks). Evidence suggested that money supply Granger-caused real GDP supporting the money non-neutrality hypothesis in the case of Portugal.
- Pollinator restoration in Brazilian ecosystems relies on a small but phylogenetically-diverse set of plant familiesPublication . Campbell, Alistair John; Gigante Carvalheiro, Luísa; Gastauer, Markus; Almeida-Neto, Mário; Giannini, Tereza CristinaThe alarming rate of global pollinator decline has made habitat restoration for pollinators a conservation priority. At the same time, empirical and theoretical studies on plant-pollinator networks have demonstrated that plant species are not equally important for pollinator community persistence and restoration. However, the scarcity of comprehensive datasets on plant-pollinator networks in tropical ecosystems constrains their practical value for pollinator restoration. As closely-related species often share traits that determine ecological interactions, phylogenetic relationships could inform restoration programs in data-scarce regions. Here, we use quantitative bee-plant networks from Brazilian ecosystems to test if priority plant species for different restoration criteria (bee species richness and visitation rates) can be identified using interaction networks; if phylogenetic relationships alone can guide plant species selection; and how restoration criteria influence restored network properties and function. We found plant species that maximised the benefits of habitat restoration for bees (i.e., generalists and those with distinct flower-visitor species) were clustered in a small number of phylogenetically-diverse plant families, and that prioritising the recovery of bee visitation rates improved both stability and function of restored plant-pollinator networks. Our approach can help guide restoration of pollinator communities, even where information on local ecosystems is limited.
- Vila Nova de São Pedro: três anos do projecto de investigação VNSP3000.Publication . Neves, César; Arnaud, José Morais; Diniz, Mariana; Martins, Andrea
- Inundações na area metropolitana de Lisboa : danos humanos e materiais e componentes de riscoPublication . Leal, Miguel; Reis, Eusébio Joaquim Marques dos; Ramos, Maria Catarina de MeloEsta dissertação tem como tema central as inundações na Área Metropolitana de Lisboa (AML), uma região afectada frequentemente por este tipo de fenómenos naturais. A elevada densidade populacional e do edificado tem-se traduzido, ao longo das últimas décadas, em elevados danos humanos e materiais causados por cheias progressivas, cheias rápidas e inundações urbanas. A posição geográfica, as características naturais das bacias hidrográficas, a extensão das áreas edificadas e a ocupação indevida de leitos de cheia favoreceram a maior concentração de ocorrências na AML Norte. Os danos humanos causados por inundações foram avaliados com recurso à base de dados DISASTER. No período 1865-2010, registaram-se 131 eventos, 396 ocorrências, 544 mortes, 3428 evacuados, 5973 desalojados e 9945 pessoas afectadas na AML. Esta região registou 24% das ocorrências, 54% das mortes e 18% dos afectados em Portugal continental. Os eventos extremos de precipitação de 1967, 1983 e 2008 contabilizaram 26% das ocorrências, 86% das mortes e 51% dos afectados na AML. As cheias rápidas foram o tipo de inundação mais importante durante o período estudado (51% das ocorrências e 61% das mortes). Os danos materiais, estimados a partir da base de dados da APS (Associação Portuguesa de Seguradores), mostraram um domínio das inundações urbanas no século XXI, quer estejam relacionadas (FREN) ou não (FUNN) com a rede de drenagem natural. No período 2000-2011, a AML registou 3676 sinistros e 13.410.434€ em indemnizações, 18% e 21% do total nacional, respectivamente. Os sinistros APS revelaram uma dependência notória relativamente às áreas edificadas e uma relação pouco significativa com a precipitação. Contudo, precipitações horárias superiores a 10,5 mm na estação de São Julião do Tojal originaram sempre pelo menos um sinistro APS num raio de 10 km. O evento de 2008 registou 24% do total de sinistros APS e 40% das indemnizações da AML. Durante este evento, a AML apresentou um comportamento mais natural, aumentando a importância dos sinistros APS ao longo dos fundos de vale (FREN). As FUNN foram mais frequentes na AML (59% dos sinistros APS), mas as FREN geraram maiores danos materiais (50% das indemnizações), confirmando o maior potencial destruidor, acentuado durante eventos com maior magnitude. As componentes do risco foram avaliadas para a bacia hidrográfica de Barcarena. Apesar de algumas das características físicas não favorecerem o desenvolvimento de cheias rápidas, existe um importante historial de ocorrências e consequências. O troço que se inicia a montante da confluência entre as ribeiras de Massamá e de Barcarena e termina junto à Fábrica da Pólvora foi identificado como o mais crítico. Foram delimitadas as áreas inundáveis para diferentes períodos de retorno e estimadas as alturas de água e velocidades do escoamento através da modelação hidráulica. Foram identificados 26 edifícios expostos com funções habitacionais, industriais ou institucionais. A vulnerabilidade estrutural foi avaliada através de uma metodologia com base em indicadores relativos às características físicas dos edifícios (vulnerabilidade intrínseca) e à magnitude das cheias. O produto da vulnerabilidade estrutural pelo valor económico dos edifícios expostos resultou na estimativa dos danos potenciais para cada edifício, permitindo a quantificação do risco (potencial).
- Alienação, exteriorização e reflexão em Hegel e MarxPublication . Bavaresco, Agemir; Iber, Christian; Lara, Eduardo GarciaA teoria da reflexão de Hegel desempenha um papel tanto lógico quanto ontológico na teoria do trabalho e da propriedade privada de Marx. Qual é o ponto de comparação entre a teoria hegeliana da reflexão e a teoria marxiana? A teoria da alienação. Em Hegel econtramos a alienação do pensamento no pensar reflexionante – o modo de operação do entendimento; em Marx, a alienação do trabalho sob a propriedade privada. Como atividade, o trabalho tem, de acordo com Marx – tal como a atividade do pensar, em Hegel – a estrutura da negatividade: a estrutura da exteriorização e do retorno a si mesmo. Nos Manuscritos Econômicos e Filosóficos (1844), em particular, Marx desenvolveu uma teoria da exteriorização do trabalho na qual a alienação impede que este cumpra o seu retorno a si. O trabalho torna‑se alienado, sai de si e permanece fora de si, pois é apropriado pela propriedade privada.
- O património encenado pelo turismo: uma reflexão teóricaPublication . Lobo, Bruna Raquel Alves Maia
- Repetition :thinking between G.W.F. Hegel’s Philosophy of History (1837) and Karl Marx’s The Eighteenth Brumaire of Louis Bonaparte (1852)Publication . Balasopoulos, AntonisTaking its cue from the untimely paradoxes manifesting themselves in some of the most visible instances of Hegel’s and Marx’s reception in the twentieth century, this essay proceeds to explore the ground between the two thinkers with particular reference to their philosophico‑historical grasp of repetition. After a number of preliminary observations on the ideological subtext involved in Marx’s reference to Hegel in the Eighteenth Brumaire of Louis Bonaparte and the temporality their intertextual conjuncture stages, I focus on four major complications that attend the comparison of Hegelian and Marxian notions of repetition, as well as on their correlation to the historical events of Revolution, Counter‑Revolution and Restoration. I conclude with some reflections on the “exit strategies” Marx and Hegel adopt vis‑à‑vis the specter of iteration as a sign of submission to the gravitational pull of the past upon the present and future.