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- Bayesian joint modeling of longitudinal and spatial survival AIDS dataPublication . Martins, Rui; Silva, Giovani L.; Andreozzi, Valeska"Joint analysis of longitudinal and survival data has received increasing attention in the recent years, especially for analyzing cancer and AIDS data. As both repeated measurements (longitudinal) and time-to-event (survival) outcomes are observed in an individual, a joint modeling is more appropriate because it takes into account the dependence between the two types of responses, which are often analyzed separately. We propose a Bayesian hierarchical model for jointly modeling longitudinal and survival data considering functional time and spatial frailty effects, respectively. That is, the proposed model deals with nonlinear longitudinal effects and spatial survival effects accounting for the unobserved heterogeneity among individuals living in the same region. This joint approach is applied to a cohort study of patients with HIV/AIDS in Brazil during the years 2002–2006. Our Bayesian joint model presents considerable improvements in the estimation of survival times of the Brazilian HIV/AIDS patients when compared with those ones obtained through a separate survival model and shows that the spatial risk of death is the same across the different Brazilian states."
- Trabalhar com a matemática em educação de infânciaPublication . Bicho, Teresa Carrilho; Boavida, Ana MariaEste estudo tem como principal objetivo compreender e analisar o modo como crianças de creche e jardim-de-infância resolvem problemas matemáticos e o que pode constranger a resolução. Em particular, procurei analisar a atividade matemática que as crianças desenvolvem quando se confrontam com problemas matemáticos e os desafios com que se deparam. Do ponto de vista metodológico, o estudo enquadra-se numa abordagem qualitativa de investigação e num paradigma interpretativo. Além disso, trata-se de uma investigação-ação orientada pela questão “como otimizar a atividade de resolver problemas matemáticos em contextos de educação de infância?”. Neste âmbito, propus a quatro crianças de creche e a 21 de jardim-de-infância um conjunto de tarefas selecionadas para, potencialmente, terem, para si, algum grau de desafio. Os principais métodos de recolha de dados foram a observação participante, a análise documental e um inquérito por questionário realizado às educadoras cooperantes. O estudo ilustra que é possível envolver crianças de creche e de jardim-de-infância numa atividade de resolução de problemas matemáticos e que esta atividade é favorecida se o contexto dos problemas estiver próximo do que fazem no dia-a-dia da sala. Durante o processo de resolução das tarefas propostas, foram mobilizadas e trabalhadas diversas noções matemáticas. Na creche, todas as crianças evidenciaram possuir conhecimentos acerca da noção topológica “dentro de” e “fora de” e algumas foram bem-sucedidas no uso do processo de classificação, tendo em conta um critério. Neste âmbito, recorreram a representações ativas. No jardim-de-infância, todas as crianças conseguiram fazer a contagem sincronizada das letras do seu nome, de indicar a quantidade de letras, o que indicia o conhecimento da noção de cardinal, e de representar esta quantidade recorrendo tanto a numerais como a representações icónicas. Além disso, foram capazes de interpretar uma tabela de modo a construir um gráfico com barras e de elaborar um pictograma, o que revela possuírem conhecimentos ao nível da literacia estatística. Por último, algumas crianças foram bem-sucedidas na descoberta de estratégias de resolução de problemas que lhes permitiram inventariar exaustivamente todas as possibilidades de resolução e contar, organizadamente, estas possibilidades. No decurso desta atividade surgiram tentativas de generalização, embora nem sempre corretas, sobressaindo o recurso a representações ativas nomeadamente à dramatização de situações. Quanto aos desafios com que se depararam destacam-se, no caso da creche, o uso correto do processo de classificação. No caso do jardim-de-infância, as crianças demonstraram dificuldades em distinguir a legenda do pictograma dos dados, em resolver um problema em que estava em jogo o sentido combinatório da multiplicação e em encontrar estratégias de generalização. O estudo indicia, ainda, que é essencial que o educador proponha tarefas diversificadas e desafiantes que, partindo sempre da curiosidade e interesse das crianças, lhes permitam trabalhar com ideias matemáticas importantes e representar adequadamente o conhecimento com que lidam.
- Sequencing CYP2D6 for the detection of poor-metabolizers in post-mortem blood samples with tramadolPublication . Fonseca, Suzana; Amorim, António; Costa, Heloísa Afonso; Franco, João; Porto, Maria João; Santos, Jorge Costa; Dias, MárioTramadol concentrations and analgesic effect are dependent on the CYP2D6 enzymatic activity. It is well known that some genetic polymorphisms are responsible for the variability in the expression of this enzyme and in the individual drug response. The detection of allelic variants described as non-functional can be useful to explain some circumstances of death in the study of post-mortem cases with tramadol. A Sanger sequencing methodology was developed for the detection of genetic variants that cause absent or reduced CYP2D6 activity, such as *3, *4, *6, *8, *10 and *12 alleles. This methodology, as well as the GC/MS method for the detection and quantification of tramadol and its main metabolites in blood samples was fully validated in accordance with international guidelines. Both methodologies were successfully applied to 100 post-mortem blood samples and the relation between toxicological and genetic results evaluated. Tramadol metabolism, expressed as its metabolites concentration ratio (N-desmethyltramadol/O-desmethyltramadol), has been shown to be correlated with the poor-metabolizer phenotype based on genetic characterization. It was also demonstrated the importance of enzyme inhibitors identification in toxicological analysis. According to our knowledge, this is the first study where a CYP2D6 sequencing methodology is validated and applied to post-mortem samples, in Portugal. The developed methodology allows the data collection of post-mortem cases, which is of primordial importance to enhance the application of these genetic tools to forensic toxicology and pathology.
- New findings in HCV genotype distribution in selected West European, Russian and Israeli regionsPublication . Kartashev, Vladimir; Döring, Matthias; Nieto, Leonardo; Coletta, Eleda; Kaiser, Rolf; Sierra, Saleta; HCV EuResist Study group; Guerrero, A.; Stoiber, H.; Paar, C.; Vandamme, A. M.; Nevens, F.; Ranst, M. Van; Cuypers, L.; Braun, P.; Ehret, R.; Obermeier, M.; Schneeweiss, S.; Scholten, S.; Römer, K.; Isernhagen, K.; Qurashi, N.; Heger, E.; Knops, E.; Neumann-Fraune, M.; Timm, J.; Walker, A.; Lübke, N.; Wedemeyer, H.; Wiesch, J. Schulze zur; Lütgehetmann, M.; Polywka, S.; Däumer, M.; Hoffmann, D.; Protzer, U.; Marascio, N.; Foca, A.; Liberto, M. C.; Barreca, G. S.; Galati, L.; Torti, C.; Pisani, V.; Perno, C. F.; Ceccherini-Silberstein, F.; Cento, V.; Ciotti, M.; Zazzi, M.; Rossetti, A.; De Luca, A.; Caudai, C.; Mor, O.; Devaux, C.; Staub, T.; Araujo, F.; Gomes, P.; Cabanas, J.; Markin, N.; Khomenko, I.; Govorukhina, M.; Lugovskaya, G.; Dontsov, D.; Mas, A.; Martró, E.; Saludes, V.; Rodríguez-Frías, F.; García, F.; Casas, P.; Iglesia, A. de la; Alados, J. C.; Pena-López, M. J.; Rodríguez, M. J.; Galán, J. C.; Suárez, A.; Cardeñoso, L.; Guerrero, M. D.; Vegas-Dominguez, C.; Blas-Espada, J.; García, R.; García-Bujalance, S.; Benítez-Gutiérrez, L.; Mendoza, C. de; Montiel, N.; Santos, J.; Viciana, I.; Delgado, A.; Martínez-Sanchez, P. A.; Fernández-Alonso, M.; Reina, G.; Trigo, M.; Echeverría, M. J.; Aguilera, A.; Navarro, D.; Bernal, S.; Lozano, M. C.; Fernández-Cuenca, F.; Orduña, A.; Eiros, J. M.; Ortíz de Lejarazu, R.; Martínez-Sapiña, A. M.; García-Díaz, A.; Haque, T.BACKGROUND: HCV affects 185 million people worldwide and leads to death and morbidities. HCV has a high genetic diversity and is classified into seven genotypes and 67 subtypes. Novel anti-HCV drugs (Direct-Acting-Antivirals) eligibility, resistance and cure rates depend on HCV geno/subtype (GT). OBJECTIVES: Analysis of epidemiological information and viral GT from patients undergoing viral genotyping in 2011-2015. STUDY DESIGN: Anonymized information from 52 centers was analyzed retrospectively. RESULTS: 37,839 samples were included in the study. We show that the GT distribution is similar throughout Western European countries, with some local differences. Here GTs 1 and 2 prevalences are lower and of GT4 higher than in all previous reports. Israel has a unique GT pattern and in South Russia the GT proportions are more similar to Asia. GTs 5 and 6 were detected in very low proportions. Three cases of the recombinant genotype P were reported in Munich (Germany). In addition, we observed that GT proportion was dependant on patientś gender, age and transmission route: GTs 1b and 2 were significantly more common in female, older, nosocomially-infected patients, while GTs 1a, 3 and 4 were more frequent in male, younger patients infected by tattooing, drug consume, and/or sexual practices. In infections acquired by drug consume, GTs 1a (35.0%) and 3 (28.1%) prevailed. In infections related to sexual practices lower proportion of GT3 (14.0%) and higher of GT4 (20.2%) were detected. GT4 was mostly abundant in MSM (29.6%). HIV coinfection was significantly associated with higher proportions GTs 1a and 4 (42.5% and 19.3%, respectively). CONCLUSION: Genotype prevalence evolves and correlates to epidemiological factors. Continuous surveillance is necessary to better assess hepatitis C infection in Europe and to take appropriate actions
- Nutritional guide for a modern woman: a strategy for health educationPublication . Dias, Maria do Rosário; Duque, Alexandra Frexes; Gaspar, Inês Filipa; Neves, Ana Cristina"In the present article, we introduce a Health Education instrument that stems from a refection on the lay knowledge, salutogenic habits and daily nutritional practices of modern women in our current society. We developed a guide aimed at modern women, where the different food groups and food hygiene and safety measures are addressed. The guide includes eleven original pictograms that help the reader to locate and look up specific issues. The guide employs the label reading and interpretation principles, following the nutrition traffic-light internationally instituted, for it renders scientific information on nutrition clear and accessible to the general population. We believe that using this guide as a central strategy in health promotion will lead its users to adopt essential changes in their eating patterns and, in so doing, contribute to prevent diseases associated to bad eating habits. We also emphasize the role of mass media in spreading the conveyed information."
- Bia’s smile: an health education instrument on cleft lip and palatePublication . Dias, Maria do Rosário; Neves, Ana Cristina; Santos, Inês; Ferreira, Rita"The human smile is a hegemonic factor to an aesthetically harmonious facial appearance and it is an elementary agent in a child’s socialisation. Children manifesting sequels associated with clef lip and palate (CLP) are likely to be targets of discriminatory attitudes; in the eyes of society, their aesthetically mutilated faces reach conspicuous stigmatizing visibility. Preventive interventions tackling social exclusion should be implemented, first and foremost, at schools; they should involve multidisciplinary teams and be aimed at enabling behavioural skills and social aptitudes among the peers of children with CLP, so as to allow deconstruction of prejudice associated with this condition. The health education tool now introduced is a children’s book titled Bia’s Smile. Its ludic-pedagogic goal is to build awareness and sensitivity in children aged 4 to 7 years old, as well as alert and inform education agents on the issue, with the ultimate object of the book being the eradication of social exclusion and bullying experienced by children with CLP. The children’s book / learning textbook to mental health was designed so as to include a set of pictograms, inserted in the story’s narrative. It should be noted that the available literature reveals a paucity of preventive programs on this issue, both at national and international level, which amplifies the pertinence of our ludicpedagogic project."
- Bidirectional DC-DC Converter with High Voltage Gain for the Charge/Discharge Control of Storage SystemsPublication . Pires, Vítor Fernão; Foito, Daniel José Medronho; Martins, J. F.This paper presents a study of a bidirectional dc-dc converter with high voltage gain to regulate the charge and discharge of electrochemical storage systems. The converter is characterized by quadratic voltage gain characteristics in both directions. In this context it can be used to regulate a dc interface between the storage system and a dc/ac converter connected to the electrical grid. It will be analysed the converter in ideal and non-ideal conditions. A control system to regulate the output voltages and currents are also proposed. Simulation results are presented in order to validate the control system associated to the converter for the charge/discharge of the storage system.
- Phonological characteristics of children with speech sound disorders: a comparative study between speakers of European and Brazilian PortuguesePublication . Martins, Ana Catarina; Nascimento, David do; Pinto, Sofia; Castro, Ana; Alves, Dina Caetano; Wertzner, Haydée
- Genetic Basis of Nonsyndromic Sensorineural Hearing Loss in the Sub-Saharan African Island Population of São Tomé and Príncipe: The Role of the DFNB1 Locus?Publication . Caroça, C; de Matos, TM; Ribeiro, D; Lourenço, V; Martins, T; Campelo, P; Fialho, G; Silva, SN; Paço, J; Caria, HelenaHearing loss (HL) is a common condition with both genetic and environmental causes, and it greatly impacts global health. The prevalence of HL is reportedly higher in developing countries such as the Sub-Saharan African island of São Tomé and Príncipe, where the deaf community is estimated to be less than 1% of the population. We investigated the role of the DFNB1 locus (GJB2 and GJB6 genes) in the etiology of nonsyndromic sensorineural hearing loss (NSSHL) in São Tomé and Príncipe. A sample of 316 individuals, comprising 136 NSSHL patients (92 bilateral, 44 unilateral) and 180 controls, underwent a clinical and audiological examination. Sequencing of the GJB2 coding region and testing for the (GJB6-D13S1830) and del(GJB6-D13S1854) GJB6 deletions were performed. A total of 311 out of 316 individuals were successfully analyzed regarding the GJB2 and GJB6 genetic variations, respectively. The frequency of the GJB2 coding mutations in patients and controls was low. Some of those coding mutations are the most commonly found in Eurasian and Mediterranean populations and have also been identified in Portugal. None of the GJB6 deletions was present. The presence of certain coding variants in São Tomé and Príncipe suggests a non-Sub-Saharan genetic influx and supports the previously reported genetic influx from European (mainly Portuguese) ancestors. In summary, DFNB1 locus does not appear to be a major contributor to NSSHL in São Tomé and Príncipe. However, the presence of both pathogenic and likely pathogenic mutations in GJB2 suggests that GJB2-related NSSHL might still occur in this population, warranting further research on GJB2 testing in NSSHL cases.
- Saúde Sazonal: Inverno e Saúde. Plano de Contingência para Temperaturas Extremas AdversasPublication . Silva, Andreia; Freitas, Graça; Pereira, Natália; Valente, PaulaNo Outono/Inverno ocorrem com frequência temperaturas baixas e há um aumento da incidência das infeções respiratórias na população, maioritariamente devidas à epidemia sazonal da gripe. No entanto, outros agentes virais e bacterianos ocorrem em simultâneo com a gripe. A Direção-Geral da Saúde (DGS) promove a implementação, desde 2004, de Planos de Contingência com o objetivo de minimizar os potenciais efeitos do frio extremo na saúde da população. O Plano de Contingência para Temperaturas Extremas Adversas está enquadrado por normativos legais, reforçando a importância e a necessidade dos serviços e estabelecimentos do Serviço Nacional de Saúde (SNS) implementarem Planos de Contingência para Temperaturas Extremas Adversas. Tal como mencionado no Plano Verão e Saúde, também o Plano Inverno e Saúde (doravante designado por Plano) está incluído no Projeto Saúde Sazonal. Pretende-se desta forma valorizar a intervenção e comunicação contínuas, ao longo do ano, adaptando-as à sazonalidade e às suas especificidades.