Bidirectional shifts in colony queen number in a socially polymorphic ant population.

The breeding system of social organisms affects many important aspects of social life. Some species vary greatly in the number of breeders per group, but the mechanisms and selective pressures contributing to the maintenance of this polymorphism in social structure remain poorly understood. Here, we take advantage of a genetic dataset that spans 15 years to investigate the dynamics of colony queen number within a socially polymorphic ant species. Our study population of Formica selysi has single- and multiple-queen colonies. We found that the social structure of this species is somewhat flexible: on average, each year 3.2% of the single-queen colonies became polygynous, and conversely 1.4% of the multiple-queen colonies became monogynous. The annualized queen replacement rates were 10.3% and 11.9% for single- and multiple-queen colonies, respectively. New queens were often but not always related to previous colony members. At the population level, the social polymorphism appeared stable. There was no genetic differentiation between single- and multiple-queen colonies at eight microsatellite loci, suggesting ongoing gene flow between social forms. Overall, the regular and bidirectional changes in queen number indicate that social structure is a labile trait in F. selysi, with neither form being favored within a time-frame of 15 years.

The Generational contract in the family : explaining regime differences in financial transfers from parents to children in Europe

The exchange of social and economic support between the generationsis one of the main pillars of both family life and welfare systems. Thedebate on how to reform the generational contract is still truncated, however, by focusing on its public dimension only, especially on pensions and health care provisions. For a full account, the transfer of resources between adult generations in the family needs to be included as well. In our previous research we have shown that intergenerationalexchange is more likely to take place but less intense in the Nordicwelfare regime than in the Continental and Southern ones. In thepresent paper we analyze the social mechanisms that create and explain this nexus between patterns of intergenerational transfers and welfare regimes. The notion that Southern European family support networksare stronger and more effective than those of Continental and Northern European countries is only partially confirmed. In Southern (and partly in Continental) countries, children are mostly supported by means of co-residence with their parents till their complete economicindependence. However, once they have left the parental home thereare fewer transfers; support tends to be restricted to children who have special needs (such as for the formation of their own family), and depends more on their parents’ resources. In the Nordic countries, in contrast, transfers are less driven by children’s needs and parentalresources.

Shifts in species and phylogenetic diversity between sapling and tree communities indicate negative density dependence in a lowland rain forest

1. As trees in a given cohort progress through ontogeny, many individuals die. This risk of mortality is unevenly distributed across species because of many processes such as habitat filtering, interspecific competition and negative density dependence. Here, we predict and test the patterns that such ecological processes should inscribe on both species and phylogenetic diversity as plants recruit from saplings to the canopy. 2. We compared species and phylogenetic diversity of sapling and tree communities at two sites in French Guiana. We surveyed 2084 adult trees in four 1-ha tree plots and 943 saplings in sixteen 16-m2 subplots nested within the tree plots. Species diversity was measured using Fisher's alpha (species richness) and Simpson's index (species evenness). Phylogenetic diversity was measured using Faith's phylogenetic diversity (phylogenetic richness) and Rao's quadratic entropy index (phylogenetic evenness). The phylogenetic diversity indices were inferred using four phylogenetic hypotheses: two based on rbcLa plastid DNA sequences obtained from the inventoried individuals with different branch lengths, a global phylogeny available from the Angiosperm Phylogeny Group, and a combination of both. 3. Taxonomic identification of the saplings was performed by combining morphological and DNA barcoding techniques using three plant DNA barcodes (psbA-trnH, rpoC1 and rbcLa). DNA barcoding enabled us to increase species assignment and to assign unidentified saplings to molecular operational taxonomic units. 4. Species richness was similar between saplings and trees, but in about half of our comparisons, species evenness was higher in trees than in saplings. This suggests that negative density dependence plays an important role during the sapling-to-tree transition. 5. Phylogenetic richness increased between saplings and trees in about half of the comparisons. Phylogenetic evenness increased significantly between saplings and trees in a few cases (4 out of 16) and only with the most resolved phylogeny. These results suggest that negative density dependence operates largely independently of the phylogenetic structure of communities. 6. Synthesis. By contrasting species richness and evenness across size classes, we suggest that negative density dependence drives shifts in composition during the sapling-to-tree transition. In addition, we found little evidence for a change in phylogenetic diversity across age classes, suggesting that the observed patterns are not phylogenetically constrained.

Evaluation of oxidative stress parameters and metabolic activities of nurses working day and night shifts

The aim of this study was to evaluate the oxidative stress and metabolic activities of nurses working day and night shifts. Intensive care unit (ICU) (n=70) and ordinary service (OS) nurses (n=70) were enrolled in the study. Just before and the end of the shifts, blood samples were obtained to measure the participants' oxidative stress parameters. Metabolic activities were analyzed using the SenseWear Armband. Oxidative stress parameters were increased at the end of the shifts for all OS and ICU nurses compared to the beginning of the shifts. Compared to the OS nurses, the ICU nurses' TAS, TOS, and OSI levels were not significantly different at the end of the day and night shifts. The metabolic activities of the OS and ICU nurses were found to be similar. As a result, the OS and ICU nurses' oxidative stress parameters and metabolic activities were not different, and all of the nurses experienced similar effects from both the day and night shifts.

The politics of contaminated sites management : institutional regime change and actor's mode of participation in the environmental management of the Bonfol Chemical Waste Landfill in Switzerland

By the end of the 1970s, contaminated sites had emerged as one of the most complex and urgent environmental issues affecting industrialized countries. The authors show that small and prosperous Switzerland is no exception to the pervasive problem of sites contamination, the legacy of past practices in waste management having left some 38,000 contaminated sites throughout the country. This book outlines the problem, offering evidence that open and polycentric environmental decision-making that includes civil society actors is valuable. They propose an understanding of environmental management of contaminated sites as a political process in which institutions frame interactions between strategic actors pursuing sometimes conflicting interests. In the opening chapter, the authors describe the influences of politics and the power relationships between actors involved in decision-making in contaminated sites management, which they term a "wicked problem." Chapter Two offers a theoretical framework for understanding institutions and the environmental management of contaminated sites. The next five chapters present a detailed case study on environmental management and contaminated sites in Switzerland, focused on the Bonfol Chemical Landfill. The study and analysis covers the establishment of the landfill under the first generation of environmental regulations, its closure and early remediation efforts, and the gambling on the remediation objectives, methods and funding in the first decade of the 21st Century. The concluding chapter discusses the question of whether the strength of environmental regulations, and the type of interactions between public, private, and civil society actors can explain the environmental choices in contaminated sites management. Drawing lessons from research, the authors debate the value of institutional flexibility for dealing with environmental issues such as contaminated sites.

Evaporation from a shallow water table: Diurnal dynamics of measured and simulated water and heat regime at the vicinity of a drying sand surface

Accurate estimates of water losses by evaporation from shallow water tables are important for hydrological, agricultural, and climatic purposes. An experiment was conducted in a weighing lysimeter to characterize the diurnal dynamics of evaporation under natural conditions. Sampling revealed a completely dry surface sand layer after 5 days of evaporation. Its thickness was <1 cm early in the morning, increasing to reach 4?5 cm in the evening. This evidence points out fundamental limitations of the approaches that assume hydraulic connectivity from the water table up to the surface, as well as those that suppose monotonic drying when unsteady conditions prevail. The computed vapor phase diffusion rates from the apparent drying front based on Fick's law failed to reproduce the measured cumulative evaporation during the sampling day. We propose that two processes rule natural evaporation resulting from daily fluctuations of climatic variables: (i) evaporation of water, stored during nighttime due to redistribution and vapor condensation, directly into the atmosphere from the soil surface during the early morning hours, that could be simulated using a mass transfer approach and (ii) subsurface evaporation limited by Fickian diffusion, afterward. For the conditions prevailing during the sampling day, the amount of water stored at the vicinity of the soil surface was 0.3 mm and was depleted before 11:00. Combining evaporation from the surface before 11:00 and subsurface evaporation limited by Fickian diffusion after that time, the agreement between the estimated and measured cumulative evaporation was significantly improved.

A Responsabilidade Sbsidiaria Tributaria Dos Gerentes e Administradores No Regime Da LGT A Sua Reversão

O estudo da responsabilidade subsidiária pelas dívidas tributárias das pessoas colectivas oferece-nos várias vias de pesquisa possíveis para a abordagem do tema, mas devido aos limites estabelecidos, decidimos então desta forma propomo-nos saber qual o sentido e alcance inerente da responsabilidade subsidiária dos gerentes e administradores das sociedades, decorrente do regime jurídico vigente que consta da aplicação do artigo 24º nº 1 da Lei Geral Tributária. Nos dias de hoje, a crescente utilização da figura da responsabilidade subsidiária por parte da administração fiscal com o objectivo de arrecadar as receitas, sempre indispensáveis, não deixa de merecer o nosso estudo no que toca ao seu desenvolvimento e interpretação, pois, o seu tratamento, tem sido substancialmente abordado pela doutrina e jurisprudência. Sendo este regime uma excepção por se aplicar em determinadas circunstâncias, e por constituir a derrogação do princípio da capacidade contributiva, demonstraremos então em que circunstância é imputada a responsabilidade subsidiária tributária aos gerentes e administradores da não entrega do valor dos tributos ao cofre do Estado à custa dos bens da sociedade. Neste contexto ainda, devido o laço entre a responsabilidade tributária e a reversão fiscal que é incontornável, pelo que torna inevitável abordar esta última, pois, trata-se do instituto que efectiva a responsabilidade tributária subsidiária, acreditamos veramente que tal tratamento possibilita uma melhor análise do instituto da responsabilidade. Embora a matéria da responsabilidade tributária tenha sido tratada abundantemente conforme já dito, contudo, é estranho que quando o assunto é o da reversão, permaneça em grande medida de um distanciamento ao nível da sua abordagem pela doutrina. Assim importa saber e compreender melhor algumas das soluções que se encontram implementadas no sistema jurídico Português.

Os Procedimentos Pré-Contratual de Escolha do Co-contratante no Regime Jurídico de Aquisições Públicas urbanas de Cabo Verde

A presente dissertação tem por objectivo analisar o Regime Jurídico das Aquisições Públicas, aprovado pela Lei n.º 17/VII/2007, de 10 de Setembro, bem como o respectivo regulamento, constante do Decreto-Lei n.º1/2009, de 5 de Janeiro. Fundamentalmente, pretende-se analisar os procedimentos de formação dos contratos administrativos regulados nestes dois diplomas. Desta análise conclui-se que os referidos diplomas não regulam todo o regime jurídico dos contratos públicos (ou das aquisições públicas), porquanto excluem as matérias relativas à execução e da extinção destes contratos. Este regime jurídico apresenta algumas imprecisões elementares de conceitos, omissões e até contradições normativas, o que é objecto da devida atenção e reflexão crítica.

O Sistema de Protecção Social de Cabo Verde: Uma análise do Regime de Protecção Social Obrigatória

Neste trabalho propomo-nos descrever o sistema de Protecção Social de Cabo Verde e analisar detalhadamente o regime de Protecção Social Obrigatória, a cargo do Instituto Nacional de Previdência Social. Para tal, numa primeira fase, procedemos à apresentação da arquitectura do sistema, com destaque para o regime de Protecção Social Obrigatória. De seguida, e no âmbito dos problemas de sustentabilidade que têm surgido em sistemas de segurança social de outros países, efectuamos uma análise de gestão da carteira constituída com os excedentes deste regime no período 2000-2009. Em síntese, concluímos que a rendibilidade da carteira no período em análise foi elevada e relativamente estável. Quanto ao risco da carteira, embora de difícil apreciação devido à falta de alguma informação relevante, tem-se mantido em níveis adequados à baixa maturidade do sistema de protecção social de Cabo Verde. A avaliação do desempenho da carteira é, portanto, aceitável.

O Regime Jurídico Do Espaço Aéreo

A história da nossa civilização nos ensinou e demonstrou que o homem sapiens desde sempre sonhava e tentava por várias formas imitar os pássaros. Mais importante é que não obstante várias tentativas falhadas, continuou a sua caminhada, acreditando que era possível um dia fazer aquilo que as aves faziam ou ainda muito melhor. A actividade humana esteve sempre e continuará no futuro procurando caminhos menos tortuosos para reduzir distâncias entre povos, descobrindo coisas e aprimorando realações humanas. A regulação jurídica do espaço aéreo, a sua história ao longo dos tempos, nasceu precisamente da necessidade dos Estados procurarem formas eficazes e eficientes de ordenar juridicamente a utilização do espaço aéreo. Hoje é quase impensável viver na terra sem pensar na utilização ordenada, criteriosa e segura do espaço áereo. Assim, a regulação do espaçao áereo desde sempre constituiu e continua a constituir uma das maiores preocupações dos Estados soberanos.