Silêncio, potência e gesto : um corpo na dança

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Proposta de uma base de dados terminológica para o ensino bilingue em Cabo Verde: nas áreas de Ciências Integradas e Matemática

A presente dissertação propõem um glossário bilingue que seja um instrumento útil no ensino bilingue em Cabo Verde. A língua cabo-verdiana é um crioulo de base portuguesa, e dessa forma muito do seu léxico é importado do português. Mas mesmo assim o sentido das palavras ou mesmo das expressões que se assemelham podem ser diferentes. Um glossário bilingue no ensino bilingue é uma ferramenta importante pois oferece equivalentes que conseguem transmitir o mesmo sentido, ou que transmitem o sentido mais adequado as realidades culturais de uma determinada sociedade. A análise dos contextos diglossicos e bilingues fornecem uma base para compreender melhor o contexto sociolinguístico de Cabo Verde. É possível verificar a forte presença do português e do cabo-verdiano. Ambas acontecem em situações complementares. O português é produzido maioritariamente, senão exclusivamente em situações formais, ao contrário do cabo-verdiano que faz parte do quotidiano da vida das pessoas. A forma como o português é adquirido/aprendido é completamente diferente da língua cabo-verdiana. O português é considerado a língua segunda, e o cabo-verdiano é a língua materna. A língua do colonizador normalmente é concedido o estatuto de oficial, e isso é visível em vários outros países que já foram colónias. A Terminologia é uma disciplina que faz interface com várias áreas. A vocabularização e terminologização permitem a interface e são processos que dão possibilidade de importar termos de outras áreas sejam elas científicas ou não. A utilização de questionários, entrevistas, uso de textos em cabo-verdiano e levantamento de termos dos manuais permitiu analisar melhor os dados e propor termos equivalentes em cabo-verdiano. As análises permitem ver as diferenças entre os códigos linguísticos, justificando assim a importância do presente trabalho.

AGNI: an API for the control of automomous service robots

With the continuum growth of Internet connected devices, the scalability of the protocols used for communication between them is facing a new set of challenges. In robotics these communications protocols are an essential element, and must be able to accomplish with the desired communication. In a context of a multi-­‐‑agent platform, the main types of Internet communication protocols used in robotics, mission planning and task allocation problems will be revised. It will be defined how to represent a message and how to cope with their transport between devices in a distributed environment, reviewing all the layers of the messaging process. A review of the ROS platform is also presented with the intent of integrating the already existing communication protocols with the ServRobot, a mobile autonomous robot, and the DVA, a distributed autonomous surveillance system. This is done with the objective of assigning missions to ServRobot in a security context.

Evolution of reputation in networks: A mean field game approach

This work models the competitive behaviour of individuals who maximize their own utility managing their network of connections with other individuals. Utility is taken as a synonym of reputation in this model. Each agent has to decide between two variables: the quality of connections and the number of connections. Hence, the reputation of an individual is a function of the number and the quality of connections within the network. On the other hand, individuals incur in a cost when they improve their network of contacts. The initial value of the quality and number of connections of each individual is distributed according to an initial (given) distribution. The competition occurs over continuous time and among a continuum of agents. A mean field game approach is adopted to solve the model, leading to an optimal trajectory for the number and quality of connections for each individual.

Definição do conceito de blended learning. Proposta metodológica no quadro da terminologia de base conceptual

Sustentado numa abordagem conceptual da Terminologia, o trabalho de investigação que a seguir se desenvolve visa propor um cenário de resposta à questão: como se define o blended learning no contexto educativo de Ensino Superior Pós-Bolonha? A necessidade de compreender, delimitar e harmonizar o conceito de blended learning no panorama actual do Ensino Superior, resulta do pressuposto de que muito embora proliferem descrições de práticas e modelos para a sua operacionalização de reconhecida qualidade - tal como sucede com outros conceitos sob alçada da educação a distância - a reflexão teórica é ainda insuficiente. Com efeito, para responder à questão supra-colocada, propõe-se o desenho de uma metodologia para construção de uma definição intensional do conceito de blended learning que herde, subsuma e melhore o conhecimento existente, identificado através da análise de texto para fins onomasiológicos e de um processo de elicitação de conhecimento tácito e de negociação discursiva junto de sujeitos especializados. A proposta de desenho metodológico que neste trabalho de esboça escora-se globalmente em três etapas: (1) etapa exploratória do domínio-objecto de estudo; (2) etapa de análise onamasiológica de evidência textual e discursiva; (3) etapa de modelização e de validação de resultados. Pretende-se, em primeiro lugar, através do estudo do espaço conceptual das modalidades de educação que se situam no continuum presença-distância sistematizar e ordenar as visões analisadas, propondo representações de educação presencial, educação a distância, e-learning, educação online, aprendizagem enriquecida por tecnologias e ainda de outras modalidades emergentes. As representações assumem o carácter de proposta aberta e decorrem da necessidade de uma primeira ordenação no sentido de topografrar, delineando - a um nível macro - o possível lugar do conceito de blended learning naquele cenário. Num segundo momento, aprofunda-se e circunscreve-se a análise, depurando a evidência observada, agora reduzida a um conjunto de contextos ricos em informação conceptual – um corpus escrito e oral de definições e descrições de blended learning – identificando candidatas a características essenciais e candidatas a características acidentais. Num terceiro momento, procede-se à modelização do conhecimento, encapsulando-a numa proposta de definição sujeita a um processo iterativo e reflexivo, constituído por um conjunto de ciclos de investigação-acção, os quais reflectem a sequência de interacções entre o terminólogo e sujeitos especializados. Defender-se-á que a experimentação deste desenho revela a produtividade de uma sequência cíclica entre a análise textual e discursiva para fins onomasiológicos, a interacção colaborativa e a introspecção. Por outras palavras, embora a natureza do estudo realizado não permita a generalização, para além da relação diádica de mediação que o terminológo estabelece com o especialista, defende-se a produtividade de um procedimento de acção-reflexão autónomo, solitário e introspectivo, no âmbito da qual o terminólogo se afirma como sujeito conceptualizador, decisor e interventor. Resultam deste percurso uma proposta de definição e de descrição de blended learning em língua portuguesa que acreditamos poder servir diferentes actores da comunidade académica envolvida neste domínio de especialidade.

On and off air: an ethnographic exploration of minority radio in Portugal

Taking a Media Anthropology’s approach to dynamics of mediated selfrepresentation in migratory contexts, this thesis starts by mapping radio initiatives produced by, for and/or with migrants in Portugal. To further explore dynamics of support of initial settlement in the country, community-making, cultural reproduction, and transnational connectivity - found both in the mapping stage and the minority media literature (e.g. Kosnick, 2007; Rigoni & Saitta, 2012; Silverstone & Georgiou, 2005) - a case study was selected: the station awarded with the first bilingual license in Portugal. The station in question caters largely to the British population presenting themselves as “expats” and residing in the Algarve. The ethnographic strategy to research it consisted of “following the radio” (Marcus, 1995) beyond the station and into the events and establishments it announces on air, so as to relate production and consumption realms. The leading research question asks how does locally produced radio play into “expats” processes of management of cultural identity – and what are the specificities of its role? Drawing on conceptualizations of lifestyle migration (Benson & O’Reilly, 2009), production of locality (Appadurai 1996) and the public sphere (Butsch, 2007; Calhoun & et al, 1992; Dahlgren, 2006), this thesis contributes to valuing radio as a productive gateway to research migrants’ construction of belonging, to inscribe a counterpoint in the field of minority media, and to debate conceptualizations of migratory categories and flows. Specifically, this thesis argues that the station fulfills similar roles to other minority radio initiatives but in ways that are specific to the population being catered to. Namely, unlike other minority stations, radio facilitates the process of transitioning between categories along on a continuum linking tourists and migrants. It also reflects and participates in strategies of reterritorialization that rest on functional and partial modes of incorporation. While contributing to sustain a translocality (Appadurai, 1996) it indexes and fosters a stance of connection that is symbolically and materially connected to the UK and other “neighborhoods” but is, simultaneously, oriented to engaging with the Algarve as “home”. Yet, besides reifying a British cultural identity, radio’s oral, repetitive and ephemeral discourse particularly trivializes the reproduction of an ambivalent stance of connection with place that is shared by other “expats”. This dynamic is related to migratory projects driven by social imaginaries fostered by international media that stimulate the search for idealized ways of living, which the radio associates with the Algarve. While recurrently localizing and validating the narrative projecting an idealized “good life”, radio amplifies dynamics among migrants that seem to reaffirm the migratory move as a good choice.

An optimized one-tube, semi-nested PCR assay for Paracoccidioides brasiliensis detection

Introduction Herein, we report a one-tube, semi-nested-polymerase chain reaction (OTsn-PCR) assay for the detection of Paracoccidioides brasiliensis. Methods We developed the OTsn-PCR assay for the detection of P. brasiliensis in clinical specimens and compared it with other PCR methods. Results The OTsn-PCR assay was positive for all clinical samples, and the detection limit was better or equivalent to the other nested or semi-nested PCR methods for P. brasiliensis detection. Conclusions The OTsn-PCR assay described in this paper has a detection limit similar to other reactions for the molecular detection of P. brasiliensis, but this approach is faster and less prone to contamination than other conventional nested or semi-nested PCR assays.

EFFECT – Efficient finite element code

The theme of this dissertation is the finite element method applied to mechanical structures. A new finite element program is developed that, besides executing different types of structural analysis, also allows the calculation of the derivatives of structural performances using the continuum method of design sensitivities analysis, with the purpose of allowing, in combination with the mathematical programming algorithms found in the commercial software MATLAB, to solve structural optimization problems. The program is called EFFECT – Efficient Finite Element Code. The object-oriented programming paradigm and specifically the C ++ programming language are used for program development. The main objective of this dissertation is to design EFFECT so that it can constitute, in this stage of development, the foundation for a program with analysis capacities similar to other open source finite element programs. In this first stage, 6 elements are implemented for linear analysis: 2-dimensional truss (Truss2D), 3-dimensional truss (Truss3D), 2-dimensional beam (Beam2D), 3-dimensional beam (Beam3D), triangular shell element (Shell3Node) and quadrilateral shell element (Shell4Node). The shell elements combine two distinct elements, one for simulating the membrane behavior and the other to simulate the plate bending behavior. The non-linear analysis capability is also developed, combining the corotational formulation with the Newton-Raphson iterative method, but at this stage is only avaiable to solve problems modeled with Beam2D elements subject to large displacements and rotations, called nonlinear geometric problems. The design sensitivity analysis capability is implemented in two elements, Truss2D and Beam2D, where are included the procedures and the analytic expressions for calculating derivatives of displacements, stress and volume performances with respect to 5 different design variables types. Finally, a set of test examples were created to validate the accuracy and consistency of the result obtained from EFFECT, by comparing them with results published in the literature or obtained with the ANSYS commercial finite element code.

Essays on bounded rationality: Individual decision and strategic interaction

Economics is a social science which, therefore, focuses on people and on the decisions they make, be it in an individual context, or in group situations. It studies human choices, in face of needs to be fulfilled, and a limited amount of resources to fulfill them. For a long time, there was a convergence between the normative and positive views of human behavior, in that the ideal and predicted decisions of agents in economic models were entangled in one single concept. That is, it was assumed that the best that could be done in each situation was exactly the choice that would prevail. Or, at least, that the facts that economics needed to explain could be understood in the light of models in which individual agents act as if they are able to make ideal decisions. However, in the last decades, the complexity of the environment in which economic decisions are made and the limits on the ability of agents to deal with it have been recognized, and incorporated into models of decision making in what came to be known as the bounded rationality paradigm. This was triggered by the incapacity of the unboundedly rationality paradigm to explain observed phenomena and behavior. This thesis contributes to the literature in three different ways. Chapter 1 is a survey on bounded rationality, which gathers and organizes the contributions to the field since Simon (1955) first recognized the necessity to account for the limits on human rationality. The focus of the survey is on theoretical work rather than the experimental literature which presents evidence of actual behavior that differs from what classic rationality predicts. The general framework is as follows. Given a set of exogenous variables, the economic agent needs to choose an element from the choice set that is avail- able to him, in order to optimize the expected value of an objective function (assuming his preferences are representable by such a function). If this problem is too complex for the agent to deal with, one or more of its elements is simplified. Each bounded rationality theory is categorized according to the most relevant element it simplifes. Chapter 2 proposes a novel theory of bounded rationality. Much in the same fashion as Conlisk (1980) and Gabaix (2014), we assume that thinking is costly in the sense that agents have to pay a cost for performing mental operations. In our model, if they choose not to think, such cost is avoided, but they are left with a single alternative, labeled the default choice. We exemplify the idea with a very simple model of consumer choice and identify the concept of isofin curves, i.e., sets of default choices which generate the same utility net of thinking cost. Then, we apply the idea to a linear symmetric Cournot duopoly, in which the default choice can be interpreted as the most natural quantity to be produced in the market. We find that, as the thinking cost increases, the number of firms thinking in equilibrium decreases. More interestingly, for intermediate levels of thinking cost, an equilibrium in which one of the firms chooses the default quantity and the other best responds to it exists, generating asymmetric choices in a symmetric model. Our model is able to explain well-known regularities identified in the Cournot experimental literature, such as the adoption of different strategies by players (Huck et al. , 1999), the inter temporal rigidity of choices (Bosch-Dom enech & Vriend, 2003) and the dispersion of quantities in the context of di cult decision making (Bosch-Dom enech & Vriend, 2003). Chapter 3 applies a model of bounded rationality in a game-theoretic set- ting to the well-known turnout paradox in large elections, pivotal probabilities vanish very quickly and no one should vote, in sharp contrast with the ob- served high levels of turnout. Inspired by the concept of rhizomatic thinking, introduced by Bravo-Furtado & Côrte-Real (2009a), we assume that each per- son is self-delusional in the sense that, when making a decision, she believes that a fraction of the people who support the same party decides alike, even if no communication is established between them. This kind of belief simplifies the decision of the agent, as it reduces the number of players he believes to be playing against { it is thus a bounded rationality approach. Studying a two-party first-past-the-post election with a continuum of self-delusional agents, we show that the turnout rate is positive in all the possible equilibria, and that it can be as high as 100%. The game displays multiple equilibria, at least one of which entails a victory of the bigger party. The smaller one may also win, provided its relative size is not too small; more self-delusional voters in the minority party decreases this threshold size. Our model is able to explain some empirical facts, such as the possibility that a close election leads to low turnout (Geys, 2006), a lower margin of victory when turnout is higher (Geys, 2006) and high turnout rates favoring the minority (Bernhagen & Marsh, 1997).

Aplicação do CRM no contexto do bloco operatório

RESUMO - Introdução: Na última década, inúmera literatura sobre temas de saúde, principalmente abordando a Segurança do Doente, foca a necessidade e a importância do conceito de trabalho em equipa e da sua implementação na atividade dos profissionais de saúde. É também referido, como exemplo a seguir, por analogia e com a devida adaptação, o conceito e a metodologia do Crew Resource Management (CRM) da aviação civil, em que vários autores reviram a evidência da sua aplicação à medicina e concluíram que era uma ferramenta útil em formação não-técnica para a prática da cirurgia segura. Porquê esta analogia entre a saúde e a aviação civil? Porquê este despertar na saúde para o trabalho em equipa e, principalmente, baseando-se na metodologia do CRM da aviação civil? Qual a importância da formação não-técnica e como pode esta ser adaptada à atividade dos profissionais da saúde, nomeadamente no bloco operatório? São estas as principais questões que irão ser investigadas e analisadas ao longo deste estudo. Objetivos: Na aviação civil, a segurança é uma das prioridades desta indústria e um dos pilares da sua sustentabilidade. Sendo a indústria da aviação civil, como a saúde, uma atividade complexa importa em primeiro lugar compreender como a segurança deve ser abordada nas organizações complexas. Depois de compreendermos os quatro pilares da segurança (política, risco, garantia e promoção) aplicados na aviação civil, analisaremos a necessidade da formação não-técnica, explicando a importância da metodologia do CRM na aviação civil e a possibilidade da “importação” dos seus conceitos pela saúde. Metodologia: Para aferirmos a necessidade de formação não-técnica pelos profissionais da saúde foi desenvolvido um inquérito aos alunos finalistas dos Cursos de Enfermagem e dos Cursos de Medicina e outro inquérito a profissionais da saúde, Enfermeiros e Médicos (Anestesista e Cirurgião) com funções no Bloco Operatório, para responderem às seguintes inquietações:  Tiveram os profissionais de saúde formação formal na sua licenciatura ou pós-graduação em temas sobre comunicação, trabalho em equipa, gestão do erro, gestão do stress, liderança, atitudes e comportamentos para um trabalho em equipa eficiente e seguro?  Tiveram formação inicial no início da sua carreira e formação recorrente equivalente sobre estes temas ao longo da sua carreira?  Estão os profissionais de saúde preparados, com conhecimentos obtidos em formação formal, para trabalhar em equipa? Pretendeu-se igualmente, através de inquérito, saber se os alunos finalistas das licenciaturas acima identificadas consideram importante para a sua futura atividade como profissionais de saúde possuírem competências não-técnicas para o trabalho em equipa para evitarem os eventos adversos. No referido inquérito será também questionado quais as matérias a abordar nas licenciaturas (ou em outra etapa da formação), consideradas necessárias para se obterem competências de trabalho em equipa e qual a opinião sobre a frequência da formação recorrente sobre estes temas. Conclusão: O trabalho ficará concluído com uma proposta de conteúdos programáticos para a formação não-técnica dos profissionais de saúde, para a sua formação inicial e para a formação recorrente ao longo da carreira, baseada na metodologia do CRM da aviação civil. Objetivo final: Como objetivo final do estudo pretende-se contribuir, através da aplicação de formação não-técnicas aos profissionais de saúde, para a melhoria da Segurança do Doente nos cuidados em saúde.

Cost of drugs manufactured by the University Hospital - role of the Central Pharmacy

The hospital pharmacy in large and advanced institutions has evolved from a simple storage and distribution unit into a highly specialized manipulation and dispensation center, responsible for the handling of hundreds of clinical requests, many of them unique and not obtainable from commercial companies. It was therefore quite natural that in many environments, a manufacturing service was gradually established, to cater to both conventional and extraordinary demands of the medical staff. That was the case of Hospital das Clinicas, where multiple categories of drugs are routinely produced inside the pharmacy. However, cost-containment imperatives dictate that such activities be reassessed in the light of their efficiency and essentiality. METHODS: In a prospective study, the output of the Manufacturing Service of the Central Pharmacy during a 12-month period was documented and classified into three types. Group I comprised drugs similar to commercially distributed products, Group II included exclusive formulations for routine consumption, and Group III dealt with special demands related to clinical investigations. RESULTS: Findings for the three categories indicated that these groups represented 34.4%, 45.3%, and 20.3% of total manufacture orders, respectively. Costs of production were assessed and compared with market prices for Group 1 preparations, indicating savings of 63.5%. When applied to the other groups, for which direct equivalent in market value did not exist, these results would suggest total yearly savings of over 5 100 000 US dollars. Even considering that these calculations leave out many components of cost, notably those concerning marketing and distribution, it might still be concluded that at least part of the savings achieved were real. CONCLUSIONS: The observed savings, allied with the convenience and reliability with which the Central Pharmacy performed its obligations, support the contention that internal manufacture of pharmaceutical formulations was a cost-effective alternative in the described setting.

Laparoscopic versus open splenectomy in the management of hematologic diseases

Splenectomy is the best available treatment for severe forms of hereditary spherocytosis, idiopathic thrombocytopenic purpura, and other hematologic conditions when these prove refractory to conservative management. It has been employed for many decades with low mortality and favorable remission rates. The use of laparoscopic splenectomy in recent years has been rapidly and even enthusiastically adopted in this field. However, the exact role of laparoscopic versus open surgery for hematologic diseases is still debated. In this study of 58 adult patients, laparoscopic procedures were compared with conventional splenectomies for similar indications. METHODS: All patients were operated on within an 8-year period. Subjects underwent similar procedures under the supervision of the same surgical school and were compared regarding age, gender, body mass index, and diagnosis. Laparoscopically managed cases (Group I, n = 30) were prospectively followed according to a written protocol, whereas the same investigation was retrospectively done with regard to traditional laparotomy (Group II, n = 28). Methods included general and demographic findings, duration and technical steps of operation, blood loss, weight of spleen, need for conversion (in minimally invasive subjects), intraoperative and postoperative complications, time until realimentation, postoperative hospitalization, mortality, and late follow-up including recurrence rate. RESULTS: Idiopathic thrombocytopenic purpura was the surgical indication in over 50% of the patients in both groups, but familial spherocytosis, thalassemia, myelodysplasia, and lymphomas were also represented in this series. Laparoscopic procedures took more time to perform (P = 0.004), and postoperative hospitalization was 2 days shorter, but this difference was not statistically significant. Postoperative hematocrit and volume of blood transfusions was equivalent, although the laparoscopic cases had a somewhat lower preoperative hematocrit (NS) and displayed better recovery for this measurement (P = 0.03). More patients in Group I were able to accept oral food on the first day than subjects undergoing conventional operations (P < 0.05). Relatively few conversions were necessary during the minimally invasive surgeries (13.3%), and postoperative early and late complications as well as recurrences occurred in similar proportions. Also, the mean weight of the spleen was not statistically different between the groups, although there was a marked numerical tendency toward larger masses in conventional procedures. No spleen in Group I exceeded 2.0 kg, whereas in Group II values up to 4.0 kg occurred, and the mean weight was 50% higher in the latter group. CONCLUSIONS: 1) Minimally invasive splenectomy was essentially comparable to open surgery with regard to safety, efficacy, and late results; 2) Advantages concerning shorter postoperative hospitalization could not be shown, despite earlier food intake and a non-significant tendency toward earlier discharge; 3) This new modality should be considered an option in cases of hematologic conditions whenever the spleen is not hugely enlarged.

Urethral catheter removal 7 or 14 days after radical retropubic prostatectomy: clinical implications and complications in a randomized study

PURPOSE: To evaluate the hypothesis that a 7-day period of indwelling catheter after radical retropubic prostatectomy is effective and safe without the need of performing cystography. METHODS: In the period from January of 2000 to July of 2002, 73 patients underwent radical retropubic prostatectomy, and these patients were prospectively randomized in 2 groups: Group 1-37 patients who had the urethral catheter removed 7 days after the procedure, and Group 2-36 patients who had the catheter removed 14 days after the surgery. The 2 groups were similar, the surgeons and the technique were the same, and no cystography was performed to evaluate the presence of leaks. RESULTS: Two patients in Group 1 had bleeding and clot retention after having the catheter taken out in the seventh postoperative day and were managed by putting the catheter back in for 7 more days. Two patients in Group 2 developed bladder neck stricture and were treated by bladder neck incision with success. The continence rate was the same, with 2 cases of incontinence in each group. About 2 pads a day were used by the patients with incontinence. The average follow-up was 17.5 months (12-36 months). No urinary fistula, urinoma, or pelvic abscesses developed after catheter removal. Two patients were excluded from the analysis of this series: 1 died with a pulmonary embolus in the third postoperative day, and 1 developed a urinary suprapubic fistula before catheter withdrawal, which was maintained for 16 days. CONCLUSION: Withdrawal of the urethral catheter 7 days after radical retropubic prostatectomy, without performing cystography, has a low rate of short-term complications that are equivalent to withdrawal 14 days after the surgery.

Otimização de esquemas terapêuticos do carcinoma da próstata envolvendo braquiterapia de baixa taxa de dose e radioterapia externa : abordagens física e radiobiológica

RESUMO: Este trabalho teve como objetivo a determinação de esquemas de tratamento alternativos para o carcinoma da próstata com radioterapia externa (EBRT) e braquiterapia de baixa taxa de dose (LDRBT) com implantes permanentes de Iodo-125, biologicamente equivalentes aos convencionalmente usados na prática clínica, com recurso a modelos teóricos e a métodos de Monte Carlo (MC). Os conceitos de dose biológica efetiva (BED) e de dose uniforme equivalente (EUD) foram utilizados, com o modelo linear-quadrático (LQ), para a determinação de regimes de tratamento equivalentes. Numa primeira abordagem, utilizou-se a BED para determinar: 1) esquemas hipofracionados de EBRT mantendo as complicações retais tardias de regimes convencionais com doses totais de 75,6 Gy, 77,4 Gy, 79,2 Gy e 81,0 Gy; e 2) a relação entre as doses totais de EBRT e LDRBT de modo a manter a BED do regime convencional de 45 Gy de EBRT e 110 Gy de LDRBT. Numa segunda abordagem, recorreu-se ao código de MC MCNPX para a simulação de distribuições de dose de EBRT e LDRBT em dois fantomas de voxel segmentados a partir das imagens de tomografia computorizada de pacientes com carcinoma da próstata. Os resultados das simulações de EBRT e LDRBT foram somados e determinada uma EUD total de forma a obterem-se: 1) esquemas equivalentes ao tratamento convencional de 25 frações de 1,8 Gy de EBRT em combinação com 110 Gy de LDRBT; e 2) esquemas equivalentes a EUD na próstata de 67 Gy, 72 Gy, 80 Gy, 90 Gy, 100 Gy e 110 Gy. Em todos os resultados nota-se um ganho terapêutico teórico na utilização de esquemas hipofracionados de EBRT. Para uma BED no reto equivalente ao esquema convencional, tem-se um aumento de 2% na BED da próstata com menos 5 frações. Este incremento dá-se de forma cada vez mais visível à medida que se reduz o número de frações, sendo da ordem dos 10-11% com menos 20 frações e dos 35-45% com menos 40 frações. Considerando os resultados das simulações de EBRT, obteve-se uma EUD média de 107 Gy para a próstata e de 42 Gy para o reto, com o esquema convencional de 110 Gy de LDRBT, seguidos de 25 frações de 1,8 Gy de EBRT. Em termos de probabilidade de controlo tumoral (igual EUD), é equivalente a este tratamento a administração de EBRT em 66 frações de 1,8 Gy, 56 de 2 Gy, 40 de 2,5 Gy, 31 de 3 Gy, 20 de 4 Gy ou 13 de 5 Gy. Relativamente à administração de 66 frações de 1,8 Gy, a EUD generalizada no reto reduz em 6% com o recurso a frações de 2,5 Gy e em 10% com frações de 4 Gy. Determinou-se uma BED total de 162 Gy para a administração de 25 frações de 1,8 Gy de EBRT em combinação com 110 Gy de LDRBT. Variando-se a dose total de LDRBT (TDLDRBT) em função da dose total de EBRT (TDEBRT), de modo a garantir uma BED de 162 Gy, obteve-se a seguinte relação:.......... Os resultados das simulações mostram que a EUD no reto diminui com o aumento da dose total de LDRBT para dose por fração de EBRT (dEBRT) inferiores a 2, Gy e aumenta para dEBRT a partir dos 3 Gy. Para quantidades de TDLDRBT mais baixas (<50 Gy), o reto beneficia de frações maiores de EBRT. À medida que se aumenta a TDLDRBT, a EUD generalizada no reto torna-se menos dependente da dEBRT. Este trabalho mostra que é possível a utilização de diferentes regimes de tratamento para o carcinoma da próstata com radioterapia que possibilitem um ganho terapêutico, quer seja administrando uma maior dose biológica com efeitos tardios constantes, quer mantendo a dose no tumor e diminuindo a toxicidade retal. A utilização com precaução de esquemas hipofracionados de EBRT, para além do benefício terapêutico, pode trazer vantagens ao nível da conveniência para o paciente e economia de custos. Os resultados das simulações deste estudo e conversão para doses de efeito biológico para o tratamento do carcinoma da próstata apresentam linhas de orientação teórica de interesse para novos ensaios clínicos. --------------------------------------------------ABSTRACT: The purpose of this work was to determine alternative radiotherapy regimens for the treatment of prostate cancer using external beam radiotherapy (EBRT) and low dose-rate brachytherapy (LDRBT) with Iodine-125 permanent implants which are biologically equivalent to conventional clinical treatments, by the use of theoretical models and Monte Carlo techniques. The concepts of biological effective dose (BED) and equivalent uniform dose (EUD), together with the linear-quadratic model (LQ), were used for determining equivalent treatment regimens. In a first approach, the BED concept was used to determine: 1) hypofractionated schemes of EBRT maintaining late rectal complications as with the conventional regimens with total doses of 75.6 Gy, 77.4 Gy, 79.2 Gy and 81.0 Gy; and 2) the relationship between total doses of EBRT and LDRBT in order to keep the BED of the conventional treatment of 45 Gy of EBRT and 110 Gy of LDRBT. In a second approach, the MC code MCNPX was used for simulating dose distributions of EBRT and LDRBT in two voxel phantoms segmented from the computed tomography of patients with prostate cancer. The results of the simulations of EBRT and LDRBT were added up and given an overall EUD in order to obtain: 1) equivalent to conventional treatment regimens of 25 fraction of 1.8 Gy of EBRT in combination with 110Gy of LDRBT; and 2) equivalent schemes of EUD of 67 Gy, 72 Gy, 80 Gy, 90 Gy, 100 Gy, and 110Gy to the prostate. In all the results it is noted a therapeutic gain using hypofractionated EBRT schemes. For a rectal BED equivalent to the conventional regimen, an increment of 2% in the prostate BED was achieved with less 5 fractions. This increase is visibly higher as the number of fractions decrease, amounting 10-11% with less 20 fractions and 35-45% with less 20 fractions. Considering the results of the EBRT simulations an average EUD of 107 Gy was achieved for the prostate and of 42 Gy for the rectum with the conventional scheme of 110 Gy of LDRBT followed by 25 fractions of 1.8 Gy of EBRT. In terms of tumor control probability (same EUD) it is equivalent to this treatment, for example, delivering the EBRT in 66 fractions of 1.8 Gy, 56 fractions of 2 Gy, 40 fractions of 2.5 Gy, 31 fractions of 3 Gy, 20 fractions of 4 Gy or 13 fractions of 5 Gy. Regarding the use of 66 fractions of 1.8 Gy, the rectum EUD is reduced to 6% with 2.5 Gy per fraction and to 10% with 4 Gy. A total BED of 162 Gy was achieved for the delivery of 25 fractions of 1.8 Gy of EBRT in combination with 110 Gy of LDRBT. By varying the total dose of LDRBT (TDLDRBT) with the total dose of EBRT (TDEBRT) so as to ensure a BED of 162 Gy, the following relationship was obtained: ....... The simulation results show that the rectum EUD decreases with the increase of the TDLDRBT, for EBRT dose per fracion (dEBRT) less than 2.5 Gy and increases for dEBRT above 3 Gy. For lower amounts of TDLDRBT (< 50Gy), the rectum benefits of larger EBRT fractions. As the TDLDRBT increases, the rectum gEUD becomes less dependent on the dEBRT. The use of different regimens which enable a therapeutic gain, whether deivering a higher dose with the same late biological effects or maintaining the dose to the tumor and reducing rectal toxicity is possible. The use with precaution of hypofractionated regimens, in addition to the therapeutic benefit, can bring advantages in terms of convenience for the patient and cost savings. The simulation results of this study together with the biological dose conversion for the treatment of prostate cancer serve as guidelines of interest for new clinical trials.

Análisis mecánico de albañilería arqueológica de adobe bajo cargas de compresión uniaxial: El caso de Huaca de la Luna

This article presents an experimental and numerical study for the mechanical characterization under uniaxial compressive loading of the adobe masonry of one of the most emblematic archaeological complex in Peru, 'Huaca de la Luna' (100-650AD). Compression tests of prisms were carried out with original material brought to the laboratory. For measuring local deformations in the tests, displacement transducers were used which were complemented by a digital image correlation system which allowed a better understanding of the failure mechanism. The tests were then numerically simulated by modelling the masonry as a continuum media. Several approaches were considered concerning the geometrical modelling, namely 2D and 3D simplified models, and 3D refined models based on a photogrammetric reconstruction. The results showed a good approximation between the numerical prediction and the experimental response in all cases. However, the 3D models with irregular geometries seem to reproduce better the cracking pattern observed in the tests.