Técnicas de extrações e procedimentos de clean-up para a determinação de hidrocarbonetos policílicos aromáticos (HPA) em sedimentos da costa do Ceará

Extraction and clean-up are essential points in polycyclic aromatic hydrocarbon (PAHs) analysis in a solid matrix. This work compares extraction techniques and clean-up procedures for PAH analysis. PAH levels, their toxicological significance and source were also evaluated in the waters of the Cocó and Ceará rivers. The efficiency of PAH recovery was higher for the soxhlet and ultrasonic techniques. PAH recovery varied from 69.3 to 99.3%. Total PAH concentration (ΣHPA) varied from 720.73 to 2234.76 µg kg-1 (Cocó river) and 96.4 to 1859.21 µg kg-1 (Ceará river). The main PAH sources are pyrolytic processes and the levels were classified as medium so that adverse effects are possible.

Parametrical study of masonry walls subjected to in-plane loading through numerical modeling

This paper deals with the numerical assessment of the influence of parameters such as pre-compression level, aspect ratio, vertical and horizontal reinforcement ratios and boundary conditions on the lateral strength of masonry walls under in-plane loading. The numerical study is performed through the software DIANA (R) based on the Finite Element Method. The validation of the numerical model is carried out from a database of available experimental results on masonry walls tested under cyclic lateral loading. Numerical results revealed that boundary conditions play a central role on the lateral behavior of masonry walls under in-plane loading and determine the influence of level of pre-compression as well as the reinforcement ratio on the wall strength. The lateral capacity of walls decreases with the increase of aspect ratio and with the decrease of pre-compression. Vertical steel bars appear to have almost no influence in the shear strength of masonry walls and horizontal reinforcement only increases the lateral strength of masonry walls if the shear response of the walls is determinant for failure, which is directly related to the boundary conditions. (C) 2011 Elsevier Ltd. All rights reserved.

Robust model predictive controller with output feedback and target tracking

A model predictive controller (MPC) is proposed, which is robustly stable for some classes of model uncertainty and to unknown disturbances. It is considered as the case of open-loop stable systems, where only the inputs and controlled outputs are measured. It is assumed that the controller will work in a scenario where target tracking is also required. Here, it is extended to the nominal infinite horizon MPC with output feedback. The method considers an extended cost function that can be made globally convergent for any finite input horizon considered for the uncertain system. The method is based on the explicit inclusion of cost contracting constraints in the control problem. The controller considers the output feedback case through a non-minimal state-space model that is built using past output measurements and past input increments. The application of the robust output feedback MPC is illustrated through the simulation of a low-order multivariable system.

Morphology of cobalt ferrite nanoparticle-polyelectrolyte multilayered nanocomposites

Novel magnetic nanocomposite films with controlled morphology were produced via the electrostatic layer-by-layer assembly of cationic CoFe(2)O(4) nanoparticles and anionic poly(3,4-ethylenedioxy thiophene)/poly(styrene sulfonic acid) (PEDOT:PSS) complex. The electrostatic interaction between nanoparticle and the polyelectrolyte complex ensured a stepwise growth of the nanocomposite film with virtually identical amounts of materials being adsorbed at each deposition cycle as observed by UV-vis spectroscopy. AFM images acquired under the tapping mode revealed a globular morphology with dense and continuous layers of nanoparticles with voids being filled with polymeric material. (C) 2010 Elsevier B.V. All rights reserved.

Impact of clinical varicocele and testis size on seminal reactive oxygen species levels in a fertile population: a prospective controlled study

Objective: To investigate: 1) the impact of clinical varicocele on reactive oxygen species (ROS) levels in neat and washed semen in a proven fertile population; and 2) the correlation between ROS levels, testicular volume, and varicocele grade in the same population of fertile men. Design: Prospective controlled clinical study. Setting: Andrology laboratory at tertiary-care hospital. Patient(s): One hundred fourteen healthy fertile men (81 normal fertile and 33 fertile with clinical varicocele) and 30 infertile patients (control subjects). Intervention(s): Standard semen analysis and measurement of sperm ROS production. Main Outcome Measure(s): Seminal parameters, seminal ROS levels, seminal leukocyte levels, clinical varicocele, and testis size. Result(s): Thirty-three of the 11.4 (29%) fertile men had clinical varicocele (grade 1, n = 14; grade 2, n = 11; and grade 3, n = 8), and the remaining 81 (71%) had a normal physical examination. Levels of ROS and semen quality did not differ significantly between the fertile men with or without varicocele. No significant differences in ROS levels in neat and washed semen were observed compared with fertile men with grades 2 and 3 varicocele and with fertile men with varicocele grade 1. The ROS levels in neat and washed semen were not significantly correlated with varicocele grade in fertile men. No significant correlations between ROS levels and testis volume were observed between the fertile groups. Conclusion(s): The presence of clinical varicocele in fertile men is not associated with higher seminal ROS levels or abnormal semen parameters. Levels of ROS are not correlated with varicocele grade or testis volume in the same population of fertile men.

Relationship between breastfeeding duration and prevalence of posterior crossbite in the deciduous dentition

Introduction: This cross-sectional retrospective epidemiologic study assessed the relationship between exclusive breastfeeding duration and the prevalence of posterior crossbite in the deciduous dentition. Methods: Clinical examinations were performed in 1377 Brazilian children (690 boys, 687 girls), 3 to 6 years old, from 11 public schools in Sao Paulo, Brazil. Based on questionnaires answered by the parents, the children were classified into 4 groups according to the duration of exclusive breastfeeding: G1, never (119 subjects); G2, less than 6 months (720 subjects); G3, 6 to 12 months (312 subjects); and G4, more than 12 months (226 subjects). The statistical analyses included the chi-square test (P < 0.05) and the odds ratio. Results: The posterior crossbite was observed in 31.1%, 22.4%, 8.3%, and 2.2% of the children, in groups G1, G2, G3, and G4, respectively. The results showed a statistically significant relationship between exclusive breastfeeding duration and the prevalence of posterior crossbite. Conclusions: Children who were breastfed for more than 12 months had a 20-fold lower risk for the development of posterior crossbite compared with children who were never breastfed and a 5-fold lower risk compared with those breastfed between 6 and 12 months. (Am J Orthod Dentofacial Orthop 2010; 137:54-8)

Contratos de gest??o: instrumentos de liga????o entre os setores do aparelho do Estado

Este artigo visa desenvolver algumas quest??es sobre os contratos de gest??o, e sobre o movimento pela ???contratualiza????o??? tanto nas rela????es entre o Estado e o setor privado, quanto nas rela????es intra-estatais. A ???contratualiza????o??? ?? ent??o abordada desde duas tradi????es: uma ?? a tradi????o advinda da administra????o p??blica, que enfatiza aspectos relacionados ?? identidade, socializa????o, sistema de cren??as e capacita????o da burocracia p??blica; a outra corresponde ?? tradi????o disciplinar da economia, mais preocupada com os aspectos microecon??micos relativos ?? estrutura de incentivos com que se deparam os atores em uma organiza????o burocr??tica. A experi??ncia nacional e internacional em ???contratualiza????o??? ?? brevemente analisada, e conclu??mos propondo algumas recomenda????es e indicando novos rumos de pesquisa.

Acrasia

Coordenação de Carlos Ceia.

Multi-agent negotiation for coalition formation and management in electricity markets

Negotiation is a fundamental tool for reaching understandings that allow each involved party to gain an advantage for themselves by the end of the process. In recent years, with the increasing of compe-titiveness in most sectors, negotiation procedures become present in practically all of them. One particular environment in which the competitiveness has been increasing exponentially is the electricity markets sector. This work is directed to the study of electricity markets’ partici-pating entities interaction, namely in what concerns the formation, management and operation of aggregating entities – Virtual Power Players (VPPs). VPPs are responsible for managing coalitions of market players with small market negotiating influence, which take strategic advantage in entering such aggregations, to increase their negotiating power. This chapter presents a negotiation methodology for the creation and management of coalitions in Electricity Markets. This approach is tested using MASCEM, taking advantage of its ability to provide the means to model and simulate VPPs. VPPs are represented as coalitions of agents, with the capability of negotiating both in the market, and internally, with their members, in order to combine and manage their individual specific characteristics and goals, with the strategy and objectives of the VPP itself.

Larva Migrans Cutânea - a Propósito de um Caso Clínico

A larva migrans cutânea representa uma das dermatoses mais frequentes nos turistas que regressam de países tropicais e sub-tropicais. O agente mais frequente é a larva Ancylostoma brasiliensis que habita no intestino de cães e gatos. Os humanos são afetados quando contatam com solo contaminado com os excrementos de animais infetados. Apresentamos o caso de uma professora, 39 anos de idade, natural e residente em Portugal que, após regressar de férias no Nordeste do Brasil, refere dermatose localizada à 4ª prega interdigital e porção adjacente do dorso dos pés, constituída por várias lesões eritematosas, pruriginosas, de trajecto serpiginoso, compatíveis com larva migrans cutânea. O quadro regrediu após terapêutica com Albendazol. Devido à maior frequência de fluxos migratórios na atualidade, as dermatoses tropicais podem tornar-se mais frequentes nos países de clima temperado. Salienta-se a importância do aconselhamento dos turistas para a prevenção desta dermatose, nomeadamente através do uso de calçado protetor.

And in his hand he baar a myghty bowe

As razões justificativas deste apontamento sobre a presença e o papel históricos do arco, enquanto instrumento bélico, na Baixa Idade Média inglesa decorrem da inclusão do Professor Hélio Osvaldo Alves no júri de doutoramento da dissertação Príncipe dos Ladrões: Robin Hood na Cultura Inglesa (c.1377-1837), por nós apresentada à Faculdade de Ciências Sociais e Humanas da Universidade Nova de Lisboa em Julho de 1996. Embora nessa altura conhecêssemos já o fascínio do Professor Hélio Alves por figuras, movimentos e projectos ‘marginais’ ou ‘marginalizados’ (fascínio que, diga-se de passagem, nos habituámos a atribuir também à sua transbordante humanidade, à capacidade alquímica de fundir inconformismo e compaixão e ao exercício solidário --- e às vezes decerto solitário --- do direito à indignação moral e cívica), foi ainda assim com surpresa que deparámos, numa das suas últimas obras e a propósito dos Luditas, com “Robin Hood revisitado” (Alves, 2002: 77-96).

Subsidizing extra jobs : the economics of marginal employment subsidies

Employment subsidies, wage subsidies, unemployment, displacement