The reform of the portuguese pension system: a micro-simulation approach

Doutoramento em Estudos do DesenvolvimentoThis thesis uses a Dynamic Microsimulation Model (DYNAPOR) to analyse the impact of a transition from a traditional Defined Benefit Pay-As-You-Go pension scheme to a Notional Defined Contribution system on both the financial and the social sustainability of the pension system in Portugal. The results show that while the NDC scenarios outperform the DB-PAYG system in terms of financial sustainability, it does so at cost of the social component. Additionally, the various features of the NDC pension system are proven to be essential in both curbing expenditure and improving adequacy and poverty alleviation.Esta tese utiliza um modelo de micro-simulação dinâmico (DYNAPOR) para analisar o impacto económico, financeiro e social da transição de um sistema de pensões pay-as-you-go de benefício definido para um sistema de contas nocionais em Portugal. Utiliza o modelo DYNAPOR para simular quatro cenários diferentes. Os resultados obtidos sugerem que uma transição para um sistema de contas nocionais semelhante ao que está em vigor na Suécia se traduz num melhoramento significativo da sustentabilidade financeira em relação ao previsto no sistema atual. Contudo, este melhoramento na sustentabilidade financeira acontece em detrimento da componente social do sistema de pensões. Mais, o impacto da componente redistributiva e de balanço automático do sistema NDC no alívio da pobreza e da despesa é comprovado pelos resultados.N/

Phylogenetic inferences of Atelinae (Platyrrhini) based on multi-directional chromosome painting in Brachyteles arachnoides, Ateles paniscus paniscus and Ateles b. marginatus

We performed multi-directional chromosome painting in a comparative cytogenetic study of the three Atelinae species Brachyteles arachnoides, Ateles paniscus paniscus and Ateles belzebuth marginatus, in order to reconstruct phylogenetic relationships within this Platyrrhini subfamily. Comparative chromosome maps between these species were established by multi-color fluorescence in situ hybridization ( FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and four previously analyzed species from all four Atelinae genera were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 82 discrete chromosome characters. The results confirmed that Atelinae represent a monophyletic clade with a putative ancestral karyotype of 2n = 62 chromosomes. Phylogenetic analysis revealed an evolutionary branching sequence \{Alouatta \{Brachyteles \{Lagothrix and Ateles\}\}\} in Atelinae and \{Ateles belzebuth marginatus \{Ateles paniscus paniscus \{Ateles belzebuth hybridus and Ateles geoffroyi\}\}\} in genus Ateles. The chromosomal data support a re-evaluation of the taxonomic status of Ateles b. hybridus. Copyright (C) 2005 S. Karger AG, Basel

Modified Zakharov equations for plasmas with a quantum correction

Quantum Zakharov equations are obtained to describe the nonlinear interaction between quantum Langmuir waves and quantum ion-acoustic waves. These quantum Zakharov equations are applied to two model cases, namely the four-wave interaction and the decay instability. In the case of the four-wave instability, sufficiently large quantum effects tend to suppress the instability. For the decay instability, the quantum Zakharov equations lead to results similar to those of the classical decay instability except for quantum correction terms in the dispersion relations. Some considerations regarding the nonlinear aspects of the quantum Zakharov equations are also offered.Comment: 4 figures. Accepted for publication in Physics of Plasmas (2004

Adubação nitrogenada e posição de amostragem em sistema silvipastoril.

Resumo: O experimento foi desenvolvido para avaliar a produtividade e a morfologia da Brachiaria brizantha cv. Marandu adubada com uréia e sulfato de amônio e em função da posição de amostragem. Foi adotado o esquema de parcelas subdivididas no espaço, sendo a parcela principal constituída por fonte de adubo nitrogenado e a subparcela constituída pela posição de amostragem da braquiária no sub-bosque do sistema silvipastoril no delineamento em blocos casualizados com seis repetições. A adubação nitrogenada e a posição de amostragem podem influenciar a produtividade e a relação F/C da braquiária em sistema silvipastoril. [Nitrogen fertilization and position sampling in silvopastoral system]. Abstract: The experiment was carried to evaluate the yield and morphology of Brachiaria brizantha cv. Marandu fertilized with urea and ammonium sulfate, and depending on the sampling position. A split plot arrangement, with six replicates in the randomized block design, was utilized. The main plot consists of a source of nitrogen fertilizer and sub-plots sampling position of pasture in understory of silvopastoral system. Nitrogen fertilization and sampling position can influence productivity and leaf lamina:stem ratio of Brachiaria in silvopastoral system

Effect of the thermal treatment on the chemical components, sorption, and shrinkage properties of Tectona grandis juvenile wood

The effect of thermal treatment on the chemical components, equilibrium moisture content (EMC), and shrinkage of teak juvenile wood was studied. Heartwood and sapwood samples were thermally-treated at 180 ºC and 200 ºC. Extractive, Klason lignin, holocellulose, and α-cellulose contents, as well as pH on untreated and thermally-treated woods, were determined. The EMC was reached at five relative humidity (RH) levels using saturated salt solutions: 86 % (KCl), 76 % (NaCl), 58 % (NaBr), 33 % (MgCl2), and 0 % (P2O5). Linear and volumetric shrinkages were calculated for all EMCs. The ratio of sorption (S), coefficient of shrinkage (h), and fiber saturation point (FSP) were also determined. Thermally-treated wood exhibited lower holocellulose and α-cellulose contents than untreated wood and increased acidity due to degradation of the hemicelluloses. The thermal treatment reduced the EMC of heartwood and sapwood. However, sapwood was more sensitive to RH variations than heartwood regardless of the treatment. Thermally-treated woods had higher hygroscopic and dimensional stabilities, and lower FSP than untreated wood. The thermal treatment did not affect radial shrinkage of the heartwood between 33 % and 86 % RH. Heartwood was more sensitive to the effect of the thermal treatment on shrinkage and degradation of cell wall polymers compared to sapwood

Behind the Intents: An In-depth Empirical Study on Software Refactoring in Modern Code Review

Code refactorings are of pivotal importance in modern code review. Developers may preserve, revisit, add or undo refactorings through changes’ revisions. Their goal is to certify that the driving intent of a code change is properly achieved. Developers’ intents behind refactorings may vary from pure structural improvement to facilitating feature additions and bug fixes. However, there is little understanding of the refactoring practices performed by developers during the code review process. It is also unclear whether the developers’ intents influence the selection, composition, and evolution of refactorings during the review of a code change. Through mining 1,780 reviewed code changes from 6 systems pertaining to two large open-source communities, we report the first in-depth empirical study on software refactoring during code review. We inspected and classified the developers’ intents behind each code change into 7 distinct categories. By analyzing data generated during the complete reviewing process, we observe: (i) how refactorings are selected, composed and evolved throughout each code change, and (ii) how developers’ intents are related to these decisions. For instance, our analysis shows developers regularly apply non-trivial sequences of refactorings that crosscut multiple code elements (i.e., widely scattered in the program) to support a single feature addition. Moreover, we observed that new developers’ intents commonly emerge during the code review process, influencing how developers select and compose their refactorings to achieve the new and adapted goals. Finally, we provide an enriched dataset that allows researchers to investigate the context and motivations behind refactoring operations during the code review process