Lower Mass Bound on the W′W^\prime mass via Neutrinoless Double Beta Decay in a 3-3-1 Model

The discovery of neutrino masses has raised the importance of studies in the context of neutrinoless double beta decay, which constitutes a landmark for lepton number violation. The standard interpretation is that the light massive neutrinos, that we observed oscillating in terrestrial experiments, mediate double beta decay. In the minimal 3-3-1 model, object of our study, there is an additional contribution that stems from the mixing between a new charged vector boson, $W^{\prime}$, and the Standard Model W boson. Even after setting this mixing to be very small, we show that tight constraints arise from the non-observation of neutrinoless double beta decay. Indeed, we derive bounds on the mass of the $W^{\prime}$ gauge boson that might exceed those from collider probes, and most importantly push the scale of symmetry breaking beyond its validity, leading to the exclusion of the minimal 3-3-1 model.Comment: 16 pages, 5 figure

Low-wage employment in Portugal: Social dimension and recent evolution

Low-wage employment is one of the main origins of poverty and social exclusion in Portugal, along with low pensions granted to elder citizens. In this paper our aim is to provide a first approach of the social dimension of low-wage employment in Portugal, analysing its incidence and profile among regions, sectors, professions, skill levels and gender. This decomposition analysis will stress the most important factors underlying the phenomenon. At a first stage we shall study wage structure and wage inequality evolution in the last decade. The incidence and evolution of low wages and minimum legal wages will be compared whith average wages, in order to evaluate the situation of the low payed vis a vis the other better paid workers. We proceed analysing low-wage decomposition by the criteria mentioned above, taken separately and in interaction, to identify the main determinants and the cumulative effects of these factors in the explanation and evolution of low wages. The main data set available is "Quadros de Pessoal" (Data base of worker characteristics provided by firms) from the MESS ( Employment and Social Security Ministry). In this study we will use directly this data base. Other statistical sources will also be used for complementary aspects. We must say that the data on these area of research are still insufficiently developed in Portugal, and that, in consequence, socio-economic knowledge on low-wage employment as a mechanism of social exclusion is still incipient. Low-wage are but one of the dimensions of social exclusion, closely related with poverty as insufficient economic resources, and is often associated with other dimensions of social exclusion in the labour market, such as unemployment vulnerability and job instability. The crucial role in this triad - low-pay, unemployment, job instability - is played by skill levels, which are particularly low in our country, as we?ll try to demonstrate. Social exclusion must however be analysed at the family unit. As long as income is concerned, wages are far the most important source, particularly for low income active families, and the ?low skills - low pay - low income? chain seems to be the major determinant of social exclusion. The evidence about this mechanism can be found in recent data on Family Budgets.

Numerical solution of linear models in economics: The SP-DG model revisited

In general, complex and large dimensional models are needed to solve real economic problems. Due to these characteristics, there is either no analytical solution for them or they are not attainable. As a result, solutions can be only obtained through numerical methods. Thus, the growing importance of computers in Economics is not surprising. This paper focuses on an implementation of the SP-DG model, using Matlab,developed by the students as part of the Computational Economics course. We also discuss some of our teaching/learning experience within the course, given for the first time in the FEP Doctoral Programme in Economics.SP-DG Model, Output, Inflation, Numerical Simulation, Teaching of Economics

Produção de grãos e aporte de carbono e nitrogênio de feijão-caupi em sistema de corte-e-trituração da vegetação secundária.

O feijão-caupi Vigna unguiculata (L.) Walp é uma das fontes alimentares mais importantes e estratégicas para as regiões tropicais e subtropicais do mundo. O objetivo deste estudo foi avaliar a produtividade e o aporte de carbono e nitrogênio por meio de resíduos do cultivo de feijão-caupi em sistema de corte-e-trituração da vegetação secundária. A produção de grãos e a biomassa da parte aérea do feijão foram avaliadas em 4 parcelas de 2,0 m x 2,0 m em 9 áreas de agricultores. A produtividade média (553,3 kg ha-1) foi menor que a média da região norte (858 kg ha-1). Houve um retorno de 211,7 kg ha-1 de carbono e 6,1 kg ha-1 de nitrogênio para o solo por meio dos resíduos do material vegetativo da parte aérea. Do ponto de vista de produção de grãos de feijão-caupi no sistema de corte-e-trituração no primeiro ano, a produção foi baixa quando comparada com a média da região norte.PIBIC-2011

Searching for olive mill waste water (OMWW) solutions: is there a potential on microalgae treatment?

Olive Mill Waste Water (OMWW) is the principal industry extraction residue of olive oil and still one of the most serious environmental problems [1]. The main purpose of this study was to evaluate the ability growth of Chlorella vulgaris under different OMWW concentrations and assess its phenolic content variations to get OMWW toxicity reduction

Produção de serapilheira em sistemas agroflorestais em Tomé-Açu, Amazônia Oriental.

A deposição de serapilheira representa um elo fundamental no fluxo de carbono entre o meio físico e o biótico, conferindo ao ecossistema do qual faz parte maior estabilidade, variando de acordo com o seu estágio sucessional e o tipo de sistema utilizado. O objetivo deste trabalho consistiu em realizar um estudo do fluxo de carbono pela deposição de serapilheira de quatro sistemas agroflorestais (SAFs) com idades e composições diferentes, no município de Tomé-Açu, Pará. O fluxo de carbono foi medido na deposição de material formador de serapilheira no período de um ano. Os SAFs foram divididos em quatro categorias, denominados SAF 1, SAF 2, SAF 3 e SAF 4, sendo (SAF 1: cacau, açaí, bananeira e seringueira, 14 anos de idade, SAF 2: cacau, açaí, bananeira, seringueira, taperebá, paricá e macacaúba, 14 anos de idade, SAF 3: cupuaçu, açaí, teca e mogno, 9 anos de idade, SAF 4:cupuaçu, açaí e paricá, 9 anos de idade). Em cada sistema, foram instaladas quatro parcelas amostrais, e dentro das parcelas foram instalados coletores para medir a deposição de material formador de serapilheira. O SAF 4 teve a maior deposição de serapilheira anual entre todos os tratamentos. A produção mensal de serapilheira apresentou uma distribuição diferenciada ao longo do ano. A estação seca foi caracterizada pela maior produção de serapilheira em todos os tratamentos. A quantidade de carbono depositada via litterfall difere significativamente em sistemas agroflorestais com idades e composições diferentes. Existe também diferença significativa entre meses dentro de um mesmo tratamento.Editores técnicos: Roberto Porro, Milton Kanashiro, Maria do Socorro Gonçalves Ferreira, Leila Sobral Sampaio e Gladys Ferreira de Sousa

Coral reef growth pattern in eastern Brazil has not changed since the Holocene

Lithocronological study of Holocene inshore reef sequences from eastern Brazil, recovered from drill holes and associated with surveys of modern reefs, allows the reconstruction of the growth pattern of reefs since their beginning in the Holocene and its comparison with present-day reefs. The interpretation of the growth pattern of the studied reefs reveals their evolution from a lithofacies of coral-algal bindstone/framestone that was deposited in a low-wave-energy environment to a lithofacies composed of coral rudstone up to a high-energy environment with accumulation of a coral framestone lithofacies. This pattern was mostly influenced by the wave energy regime, regional sea-level history and shallow antecedent reef substrate. Despite the stages of reef evolution not occurring synchronously over time, they did not exhibit any regional variation during their development. The coral fauna that built the reefs did not change much since the beginning of reef growth (approximately 7,000 yr BP), suggesting that the environmental conditions in this region have most likely remained favorable for the development of coral reefs. The coral fauna that built the Brazilian reefs is mostly composed of resistant and well-adapted endemic coral species, which biodiversity has remained constant throughout the development of the reef