A gestão da observação nas aulas de campo em ciências

Este trabalho aborda o papel da observação na construção de conhecimento em aulas expositivas no ensino de ciências. A partir da análise da interação discursiva entre professor e alunos em aulas expositivas de campo para estudo de ecossistemas costeiros, apontamos algumas estratégias de controle temático utilizadas na construção da narrativa científica. Os resultados sugerem que a observação é utilizada pelo professor como estratégia retórica, definindo os itens temáticos que participam da construção da narrativa, e como recurso de produção de referenciais compartilhados, por meio da definição do ponto de vista comum de observação. A função de marco referencial da observação controlada do meio material parece não se encaixar nas categorias de marco social e de marco específico propostas por Coll et al. (1992), sendo sugerida a categoria de marco referencial empírico

A gestão da observação nas aulas de campo em ciências

Este trabalho aborda o papel da observação na construção de conhecimento em aulas expositivas no ensino de ciências. A partir da análise da interação discursiva entre professor e alunos em aulas expositivas de campo para estudo de ecossistemas costeiros, apontamos algumas estratégias de controle temático utilizadas na construção da narrativa científica. Os resultados sugerem que a observação é utilizada pelo professor como estratégia retórica, definindo os itens temáticos que participam da construção da narrativa, e como recurso de produção de referenciais compartilhados, por meio da definição do ponto de vista comum de observação. A função de marco referencial da observação controlada do meio material parece não se encaixar nas categorias de marco social e de marco específico propostas por Coll et al. (1992), sendo sugerida a categoria de marco referencial empírico

Early or Delayed Enteral Feeding for Infants with Abnormal Antenatal Doppler Flow Patterns

Introdução: O principal objetivo deste estudo foi determinar o efeito da introdução de alimentação entérica precoce comparado com introdução tardia, na incidência de morbilidade gastrointestinal e tempo até alimentação entérica total, em recém- -nascidos com alteração de fluxos em ecografia pré-natal. Métodos: Análise retrospetiva dos recém-nascidos internados numa unidade de cuidados intensivos neonatais de nível III, em Portugal, entre janeiro de 2004 e dezembro de 2013 com alteração de fluxos em ecografia pré-natal. Foram criados dois grupos baseados no tempo até introdução de primeira alimentação entérica: grupo de alimentação precoce (≤48 horas) e grupo de alimentação tardia (> 48 horas). Os resultados principais foram morbilidade gastrointestinal e mortalidade devido a complicações gastrointestinais. Resultados: Foram incluídos 46 (47%) de recém-nascidos no grupo de alimentação precoce e 52 (53%) no grupo de alimentação tardia. Não houve diferenças significativas na morbilidade gastrointestinal, incluindo enterocolite necrosante, perfuração ou cirurgia gastrointestinal, íleus séptico ou intolerância alimentar. A alimentação precoce resultou numa diminuição significativa da sepsis tardia (p=0,016; odds ratio 0,276; intervalo de confiança 95% 0,096-0,789). Discussão: A introdução precoce de alimentação entérica poderá não ter efeitos significativos na incidência de morbilidade gastrointestinal em recém-nascidos com alteração de fluxos em ecografia pré-natal. Houve uma redução significativa na sepsis tardia, sem condicionar um aumento de risco de morbilidade gastrointestinal.Introduction: The main objective of this study was to determine the effect of early versus late enteral feeding on the incidence of gastrointestinal morbidity and on time to establish full enteral feeding in neonates with abnormal antenatal Doppler flow patterns. Methods: We retrospectively analysed neonates admitted to a level III neonatal intensive care unit in Portugal between January 2004 and December 2013 with abnormal antenatal Doppler flow patterns. Two groups were created based on the time of first enteral feeding: early feeding group (≤48 hours) and late feeding group (> 48 hours). Primary outcomes were gastrointestinal morbidity and death due to gastrointestinal complications. Results: Forty-six (47%) infants were included in the early feeding group and 52 (53%) in the late feeding group. There was no statistical difference in gastrointestinal morbidity, including necrotising enterocolitis, gastrointestinal perforation or surgery, septic ileus or feeding intolerance. Early feeding resulted in a significant decrease in late-onset sepsis (p=0.016; odds ratio 0.276; 95% confidence interval 0.096-0.789). Discussion: Early introduction of enteral feeding may not have a significant effect on the incidence of gastrointestinal morbidity in neonates with abnormal antenatal Doppler flow patterns. There was a significant reduction in late-onset sepsis, without incurring an increased risk of gastrointestinal morbidity.info:eu-repo/semantics/publishedVersio

Elastic timber gridshells - structures with an integrated design

A timber gridshell is a special type of structure that establishes a new framework for lightweight construction. It is possible to create a wide variety of shapes and geometries, therefore guaranteeing an enormous architectural freedom. However, given the variety of forms and the difficulty they can present, it is necessary to use different tools and information to support this complex process.The present paper explores the interaction between the information and the different tools used by architects and engineers during the designing and construction process of an elastic timber gridshell, by presenting a real case study with 42m(2)(6,5mx6,5m) after being erected, built with the intent to explore the design and constructive process together with integrated form finding methods. In the paper, both the architect's and the engineer's optimization goals are performed on the same case study. The designing process will be presented and the construction of the elastic gridshell will be described.Una malla estructural de madera es un tipo especial de estructura que establece un nuevo marco para la construcción ligera. Es posible crear una amplia variedad de formas y geometrías, garantizando así una enorme libertad arqui-tectónica. Sin embargo, dada la variedad de formas y la complejidad que pueden presentar es necesario utilizar difer-entes herramientas e información para avalar este complejo proceso. El presente trabajo explora la interacción entre la información y las diferentes herramientas utilizadas por arquitectos e ingenieros durante el proceso de diseño y construcción de una malla elástica de madera, presentando un caso de estu-dio real con 42m2 (6,5mx6,5m), después de la elevación, construida con la intención de explorar el diseño y el proceso constructivo junto con métodos de integración de “form finding”. En el trabajo, los objetivos de optimización tanto del arquitecto como del ingeniero se realizan sobre el mismo caso de estudio. Se presentará el proceso de diseño y se descri-birá la construcción de la malla elástica.This work is financed by FEDER funds through the Competitively Factors Operational Programme - COMPETE and by national funds through FCT -Foundation for Science and Technology within the scope of the project POCI01-0145-FEDER-007633. The support of the Foundation for Science and Technology (FCT) through doctoral fellowship SFRH/BD/104677/2014 is grateful

Concrete retrofitting using CFRP and geopolymer mortars

A new development in the repair and strengthening of reinforced concrete systems is the use of carbon fiber reinforced polymers (CFRP) strips bonded to concrete substrate with epoxy resins. It has been reported that epoxy adhesive are extremely sensitive to high temperatures. Some authors conclude that the epoxy temperature should not exceed 70 ºC in order to safeguard the adhesiveness of the epoxy and, thus, the integrity and adequate functioning of CFRP. It is noted that even frequently exposure to direct sunlight causes temperatures higher than 70 ºC. Since geopolymers are known to possess high stability at high temperature, these materials can be an alternative to epoxy resins. This papers presents results about the use of metakaolin based geopolymers mortars to insure the adhesion between the CFRP and the concrete substrate. Several compositions of geopolymer mortars were executed by varying the percentage of binder, sand/binder ratio and the concentration of sodium hydroxide. It was found that geopolymer mortars demonstrate very promising performances, having obtained a high mechanical resistance and a good adhesion to concrete. On the other hand the adhesion between CFRP and geopolymer mortars proved to be smaller than expected which could be due, to the fact that the composition of the mortar was not optimized or even to the nature of the CFRP

Concrete retrofitting using metakaolin geopolymer mortars and CFRP

This paper presents results about the use of metakaolin based geopolymers mortars for retrofitting purposes. Two main situations are addressed, the use of geopolymeric mortars as a repairing layer or as a binding agent to insure the adhesion between CFRP sheets and the concrete substrate. Several compositions of metakaolin geopolymer mortars were executed by varying the percentage of sand/binder mass ratio and the concentration of sodium hydroxide. It was found that metakaolin geopolymer mortars show a high mechanical resistance and a relevant adhesion to the concrete substrate. Although their adhesion strength is lower than the one present by commercial pre-pack repair mortars, they are very cost-effective (5 to 10 times less expensive). On the other hand, the adhesion strength between CFRP and geopolymer mortars proved to be lower than expected which could be due to the fact that the composition of the geopolymeric mortars was not optimized and also to the fact that the CFRP used was not prone to this kind of application

Skin Disease in Liver and Kidney Transplant Recipients Referred to the Department of Dermatology and Venereology

Introdução: Foram descritas várias doenças cutâneas em doentes transplantados, em relação com a terapêutica imunossupressora instituída. Pretendemos caracterizar o espectro clínico das patologias dermatológicas e comparar os diagnósticos entre os doentes transplantados hepáticos e os doentes transplantados renais. Material e Métodos: Estudo descritivo e retrospectivo através da consulta de processos clínicos de todos os doentes submetidos a transplante hepático ou renal entre 2000 - 2010 referenciados à Consulta de Dermatologia e Venereologia. Resultados: Observámos 319 doentes transplantados (23,5%) e apurámos 410 diagnósticos (230 na sub-população com transplante hepático e 180 na sub-população com transplante renal), divididos em quatro grupos: 1) infecções cutâneas; 2) cancro cutâneo ou lesões precursoras; 3) manifestações cutâneas relacionadas com efeitos secundários de fármacos; 4) outras patologias dermatológicas não iatrogénicas. As infecções cutâneas foram as mais observadas (42,2%), em média 32,7 meses após o transplante. Este grupo incluiu 20,5% de infecções fúngicas, 12,7% virais e 8,5% bacterianas. Identificámos patologia tumoral e lesões precursoras em 11,7% dos casos, em média 44,8 meses após o transplante e assumindo maior importância na sub-população com transplante renal (20,6% vs 4,8% nos transplantados hepáticos; P < 0,001). Os transplantados renais apresentaram predomínio de carcinomas espinocelulares (CEC) sobre os casos de carcinomas basocelulares (CBC), numa razão CEC:CBC de 1,3:1 mas nos transplantados hepáticos verificou-se uma razão CBC: carcinomas de 3,5:1. Ocorreram efeitos secundários de fármacos em 10,5% dos casos e outras patologias dermatológicas não iatrogénicas em 35,6%. Discussão: Apesar da patologia tumoral ser a mais referida na literatura, as infecções cutâneas foram as mais observadas na nossa amostra. As diferenças significativas entre as duas sub-populações estudadas podem estar relacionadas com o maior grau de imunossupressão a que os doentes transplantados renais estão sujeitos. Conclusão: Dada a elevada frequência de patologia cutânea nestes doentes é essencial incluir o acesso a consultas de Dermatologia e Venereologia nos cuidados multi-disciplinares pós-transplante

An introduction to Lipschitz geometry of complex singularities

The aim of this paper to introduce the reader to a recent point of view on the Lipschitz classifications of complex singularities. It presents the complete classification of Lipschitz geometry of complex plane curves singularities and in particular, it introduces the so-called bubble trick and bubble trick with jumps which are key tools to study Lipschitz geometry of germs. It describes also the thick-thin decomposition of a normal complex surface singularity and built two geometric decompositions of a normal surface germ into standard pieces which are invariant by respectively inner and outer bilipschitz homeomorphisms. This leads in particular to the complete classification of Lipschitz geometry for the inner metric.Comment: 50 pages, 36 figure

Multi-target neuroprotective effects of herbal medicines for Alzheimer's disease

Ethnopharmacological relevance: Alzheimer's disease is the most common form of dementia, but its treatment options remain few and ineffective. To find new therapeutic strategies, natural products have gained interest due to their neuroprotective potential, being able to target different pathological hallmarks associated with this disorder. Several plant species are traditionally used due to their empirical neuroprotective effects and it is worth to explore their mechanism of action. Aim of the study: This study intended to explore the neuroprotective potential of seven traditional medicinal plants, namely Scutellaria baicalensis, Ginkgo biloba, Hypericum perforatum, Curcuma longa, Lavandula angustifolia, Trigonella foenum-graecum and Rosmarinus officinalis. The safety assessment with reference to pesticides residues was also aimed. Materials and methods: Decoctions prepared from these species were chemically characterized by HPLC-DAD and screened for their ability to scavenge four different free radicals (DPPH•, ABTS•+, O2•‒ and •NO) and to inhibit enzymes related to neurodegeneration (cholinesterases and glycogen synthase kinase-3β). Cell viability through MTT assay was also evaluated in two different brain cell lines, namely non-tumorigenic D3 human brain endothelial cells (hCMEC/D3) and NSC-34 motor neurons. Furthermore, and using GC, 21 pesticides residues were screened. Results: Regarding chemical composition, chromatographic analysis revealed the presence of several flavonoids, phenolic acids, curcuminoids, phenolic diterpenoids, one alkaloid and one naphthodianthrone in the seven decoctions. All extracts were able to scavenge free radicals and were moderate glycogen synthase kinase-3β inhibitors; however, they displayed weak to moderate acetylcholinesterase and butyrylcholinesterase inhibition. G. biloba and L. angustifolia decoctions were the less cytotoxic to hCMEC/D3 and NSC-34 cell lines. No pesticides residues were detected. Conclusions: The results extend the knowledge on the potential use of plant extracts to combat multifactorial disorders, giving new insights into therapeutic avenues for Alzheimer's disease

Resolving galaxies in time and space: II: Uncertainties in the spectral synthesis of datacubes

In a companion paper we have presented many products derived from the application of the spectral synthesis code STARLIGHT to datacubes from the CALIFA survey, including 2D maps of stellar population properties and 1D averages in the temporal and spatial dimensions. Here we evaluate the uncertainties in these products. Uncertainties due to noise and spectral shape calibration errors and to the synthesis method are investigated by means of a suite of simulations based on 1638 CALIFA spectra for NGC 2916, with perturbations amplitudes gauged in terms of the expected errors. A separate study was conducted to assess uncertainties related to the choice of evolutionary synthesis models. We compare results obtained with the Bruzual & Charlot models, a preliminary update of them, and a combination of spectra derived from the Granada and MILES models. About 100k CALIFA spectra are used in this comparison. Noise and shape-related errors at the level expected for CALIFA propagate to 0.10-0.15 dex uncertainties in stellar masses, mean ages and metallicities. Uncertainties in A_V increase from 0.06 mag in the case of random noise to 0.16 mag for shape errors. Higher order products such as SFHs are more uncertain, but still relatively stable. Due to the large number statistics of datacubes, spatial averaging reduces uncertainties while preserving information on the history and structure of stellar populations. Radial profiles of global properties, as well as SFHs averaged over different regions are much more stable than for individual spaxels. Uncertainties related to the choice of base models are larger than those associated with data and method. Differences in mean age, mass and metallicity are ~ 0.15 to 0.25 dex, and 0.1 mag in A_V. Spectral residuals are ~ 1% on average, but with systematic features of up to 4%. The origin of these features is discussed. (Abridged)Comment: A&A, accepte