596 research outputs found

    Spectrophotometric characterization of simple glazings for a modular façade

    Get PDF
    A large variety of transparent materials is available for uses in buildings façades and all glazing properties must be considered in their choice. Such a selection should be a careful process of evaluation and weighing of tradeoffs. The correct glazing specifications for façades can reduce energy consumption in buildings, because the heat exchange and passage of radiation into the building as light and heat occur through transparent surfaces. Therefore, glazing significantly contributes to the heat transfer between outdoor and indoor spaces, which act directly on daylighting and thermal comfort. This manuscript addresses a spectrophotometric characterization of glazings for the study of components for the design of a modular façade system based on the climate of Portugal. The study focused on results of spectrophotometric measurements of an optical behavior in different solar spectrum intervals (ultraviolet, visible and near infrared), specifically the transmittance of some types of simple glazings. The results show the percentage of transmission to spectrum intervals, which enabled the analysis (OK?) of the efficiency of the glazing regarding daylighting and correlation to the thermal performance. Indications for specifications and adequate uses based on transmission of transparent surfaces have been obtained and complemented the datasheets available from the manufactures.The authors gratefully acknowledge the financial support provided by Erasmus Mundus ISAC – Improving Skills Across Continents for this research.info:eu-repo/semantics/publishedVersio

    Princípio da sala de aula invertida: uma ferramenta para o ensino de química em tempos de pandemia / Principle of inverted classroom: a tool for teaching chemistry in pandemic times

    Get PDF
    O artigo descreve um relato de experiência relacionado à implantação do método sala de aula invertida na disciplina de Química II, no Instituto Federal do Acre – Campus Cruzeiro do Sul. O conteúdo explorado foi Unidades de Concentração/Concentração Comum, tendo como ferramenta de pesquisa um rótulo de embalagens alimentícias. A atividade foi iniciada a partir da disponibilização de um roteiro de estudos/sequências de ações de aprendizagem nos grupos de Whatsapp, e-mails, sendo o Classrrom o ambiente virtual como sala de aula e receptor dos materiais de apoio aos estudos. A necessidade da utilização de metodologias diferenciadas, a Sala de Aula Invertida, baseia-se no contexto atual, ou seja, o isolamento em tempos de pandemia e a diminuição ou paralisação da rotina de aprendizagem. A metodologia utilizada, configurou-se em uma ferramenta viável para potencializar e dar continuidade na rotina de estudos de maneira que ficou evidenciado a participação dos estudantes em todas as ações propostas. A aprendizagem no conteúdo proposto, ficou notório com a conclusão do estudo dirigido acerca da importância do rótulo no cotidiano do aluno e nos cálculos desenvolvidos, a partir dos dados retirados na embalagem escolhida pelo estudante. Fica evidenciado, portanto, que a metodologia aplicada, proporcionou ao estudante a possibilidade de ser o centro na construção do conhecimento e ao professor de contribuir através do papel de mediador e orientador da aprendizagem. 

    Photocatalytic Activity and UV-Protection of TiO(2) Nanocoatings on Poly(lactic acid) Fibres Deposited by Pulsed Magnetron Sputtering

    Get PDF
    The application of nanocoatings in the textile finishing is increasingly being explored because they open a whole new vista of value-addition possibilities in the textile sector. In the present work, low temperature pulsed DC magnetron sputtering method was used to create functional TiO2 nanocoatings on poly(lactic acid) textile fibres surfaces. In this study, the principal objectives in the application of TiO2 nanocoatings to textile materials are to impart UV protection functions and self-cleaning properties to the textile substrates. The TiO2 films were characterized by X-ray diffraction, scanning electron microscopy, atomic force microscopy, transmission electron microscopy, UV-visible spectroscopy and contact angle analysis. The Photocatalytic activity of the films was tested by measuring the photodegradation rates of rhodamine-B dye aqueous solution under UV light irradiation. The ultraviolet protection function was tested according to the Australian/New Zealand standards. It was observed that the TiO2 nanocoatings on poly(lactic acid) fibres showed an excellent ultraviolet protection (>40) function and the photocatalytic efficiency was maintained even after a strong washing treatment.We acknowledge the PhD grant of J. H. O. Nascimento to Programa ALBAN-"Programa de bolsas de alto nivel da Uniao Europeia para a America Latina, bolsa no E06D104090BR.

    Development of a radioimmunoassay for serum 21-deoxycortisol and its potential application in the diagnosis of congenital adrenal hyperplasia

    Get PDF
    Serum 21-deoxycortisol (21DF) has been considered a useful hormonal marker for the diagnosis of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD). Although several radioimmunoassay (RIA) methods for 21DF have been reported, none are commercially available. We developed a RIA adapted for 21DF determination, preceded by ether-extraction and liquid chromatographic separation (HPLC) of samples. The assay was employed to evaluate children (15F/10M) with the classic form of 21OHD and a control group (5F/8M). The antibody obtained, in addition to efficient HPLC separation, permitted tritiated cortisol instead of 21DF to be used, since labeled ³H-21DF is expensive and difficult to obtain. Serum cortisol levels were reduced in patients with 21OHD (48h following therapy withdrawal) as compared to controls (2.1±2.1 vs. 16.2±7.0mug/dl), whereas serum levels of 21DF were significantly elevated (1,359±853ng/dl, ranging from 434 to 3,079) in the former, but consistently below the sensitivity limit of the assay (156ng/dl) in the latter group. The reported method, although devoid of sensitivity for its application in normal subjects, permits 21DF to be quantified in patients with 21OHD, with adequate sensitivity and specificity to diagnose and follow patients with this condition.O 21-deoxicortisol (21DF) sérico tem sido considerado um excelente marcador para o diagnóstico da hiperplasia adrenal congênita (HAC) por deficiência de 21-hidroxilase (D21OH). Embora vários métodos de radioimunoensaio (RIE) tenham sido descritos para 21DF, nenhum deles está disponível comercialmente. Desenvolvemos um RIE adaptado para a dosagem de 21DF, com extração prévia das amostras com éter e separação por cromatografia líquida (HPLC). O ensaio foi aplicado para a avaliação de crianças portadoras da forma clássica de D21OH (15F/10M) e um grupo controle (5F/8M). O anticorpo obtido, associado à eficiência da separação por HPLC, viabilizou o emprego do cortisol triciado neste RIE. Enquanto nos pacientes os níveis de cortisol estavam reduzidos (48h após suspensão do tratamento) em comparação com o grupo controle (2,1±2,1 vs. 16,2±7,0mig/dl), os valores do 21DF sérico estavam bastante elevados (1.359±853ng/dl, variando de 434 a 3.079), embora consistentemente abaixo do limite de sensibilidade (156ng/dl) no grupo controle. O presente método, mesmo destituído de sensibilidade para aplicação em indivíduos normais, permite a quantificação deste esteróide em portadores de D21OH, com a sensibilidade e a especificidade necessárias para o diagnóstico e acompanhamento desta condição clínica.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo (UNIFESP) EPM Departamento de MedicinaHospital Infantil Darcy Vargas Serviço de Endocrinologia PediátricaHôpital Saint Louis Service de Biologie HormonaleUNIFESP, EPM, Depto. de MedicinaSciEL

    Supplementing alpha-tocopherol (vitamin E) and vitamin D3 in high fat diet decrease IL-6 production in murine epididymal adipose tissue and 3T3-L1 adipocytes following LPS stimulation

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>It is well known that high fat diets (HFDs) induce obesity and an increase in proinflammatory adipokines. Interleukin-6 (IL-6) is considered the major inflammatory mediator in obesity. Obesity is associated with a vitamin deficiency, especially of vitamins E and D3. We examined the effects of vitamin D3 and vitamin E supplementation on levels of IL-6 and IL-10 (as a marker of anti-inflammatory cytokines since, a balance between pro- and anti-inflammatory cytokines is maintained) protein expression in adipose tissue of mice provided with an HFD. Additionally, we measured the effects of vitamin E and vitamin D3 treatment on LPS-stimulated 3T3-L1 adipocytes IL-6 and IL-10 secretion.</p> <p>Results</p> <p>IL-6 protein levels and the IL-6/IL-10 ratio were decreased in epididymal white adipose tissue in groups receiving vitamins E and D3 supplementation compared to the HFD group. A 24-hour treatment of vitamin D3 and vitamin E significantly reduced the IL-6 levels in the adipocytes culture medium without affecting IL-10 levels.</p> <p>Conclusions</p> <p>Vitamin D3 and vitamin E supplementation in an HFD had an anti-inflammatory effect by decreasing IL-6 production in epididymal adipose tissue in mice and in 3T3-L1 adipocytes stimulated with LPS. Our results suggest that vitamin E and D3 supplementation can be used as an adjunctive therapy to reduce the proinflammatory cytokines present in obese patients.</p

    Production of photocatalytic road pavements using TiO2 nanoparticles

    Get PDF
    posterMan’s activity and mismanagement of resources conducted to dangerous levels of pollution in water, air and earth and to incalculable deficiencies, harmful to the physical and social health of mankind. Industrial activities, heating systems and road traffic are the main responsibles for the emission of pollutant gases such as nitrogen oxides (NOx) and volatile organic compounds (VOCs). As so, its harmful impacts are observed far beyond large cities and jam-packed streets. It is important to refer that the health costs related only with road traffic air pollution represents 0.9%-2.7% of the gross domestic product (GDP) in France, for example. Under this context, the combination of nanostructured titanium dioxide (TiO2) and bituminous formulations represents a tool, with considerable degree of innovation, towards the reduction of environmental impacts. In this work, conventional hot mix asphalt (HMA) was produced with standard materials to play the role of a control sample. Afterwards, an aqueous solution of TiO2 nanoparticles was sprayed over sample’s surface. By another hand, a HMA samples was also modified through the volume incorporation of small quantities of TiO2 nanoparticles and recycled glass cullets. It is expected that the inclusion of glass in the asphalt formulations should promote an in-depth conduction and entrapment of light , thus enhancing the photocatalytic performance of this samples. Scanning Electron Microscopy (SEM) analysis were conducted in order to infer about the morphology of the modified HMA samples and the surface as well as the in-depth dispersion of TiO2 nanoparticles and recycled glass cullets. The produced samples were also subjected to wearing tests using the tire-road contact method. Before and after the wearing process, the photocatalytic efficiency was evaluated via the decomposition rate of an aqueous solution of Methylene Blue (MB) under UV light irradiation

    Acute exhaustive exercise regulates IL-2, IL-4 and MyoD in skeletal muscle but not adipose tissue in rats

    Get PDF
    Background: The purpose of this study was to evaluate the effect of exhaustive exercise on proteins associated with muscle damage and regeneration, including IL-2, IL-4 and MyoD, in extensor digitorum longus (EDL) and soleus muscles and mesenteric (MEAT) and retroperitoneal adipose tissues (RPAT). Methods: Rats were killed by decapitation immediately (E0 group, n = 6), 2 (E2 group, n = 6) or 6 (E6 group, n = 6) hours after the exhaustion protocol, which consisted of running on a treadmill at approximately 70% of VO(2max) for fifty minutes and then at an elevated rate that increased at one m/min every minute, until exhaustion. Results: The control group (C group, n = 6) was not subjected to exercise. IL-2 protein expression increased at E0 in the soleus and EDL; at E2, this cytokine returned to control levels in both tissues. In the soleus, IL-2 protein expression was lower than that in the control at E6. IL-4 protein levels increased in EDL at E6, but the opposite result was observed in the soleus. MyoD expression increased at E6 in EDL. Conclusion: Exhaustive exercise was unable to modify IL-2 and IL-4 levels in MEAT and RPAT. The results show that exhaustive exercise has different effects depending on which muscle is analysed.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP, Brazil)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq, Brazil

    Recorte circular de cenas computacionais aplicado na separação de íris humana

    Get PDF
    O reconhecimento de padrões da íris humana é um processo não invasivo e que permite a extracção de características individuais. A localização e separação da íris do restante da imagem é fundamental para o bom desempenho dos métodos desenvolvidos nesta área. O isolamento da íris costuma ser um processo que exige a varredura da imagem e a comparação da localização de cada um de seus pixels. Como esta possui formato arredondado, o recorte de cenas computacionais, com janela de corte circular, pode ser aplicado nas imagens de íris para fazer este isolamento. No entanto, encontrar os limites de uma janela de visualização é um processo exigente computacionalmente, principalmente para estruturas de dados do tipo bitmap, que devem ser processadas pixel a pixel. Na tentativa de reduzir o processamento para tornar viável a aplicação na separação de íris, este trabalho usa os conceitos de hashing e a equação da circunferência para definir os pontos da imagem original bitmap pertencentes a uma área de visualização circular, sem a necessidade de percorrer todos os pixels da mesma. Apresenta-se o resultado da aplicação deste método para a separação da íris humana em imagens bitmap, sem a necessidade de comparar a localização de todos os seus pixels

    Tinctorial behavior of curaua and banana fibers and dyeing wastewater treatment by porous alumina membranes

    Get PDF
    Physicochemical and dyeing properties using reactive dyes of curaua and banana fibers were studied by means of color strength (K/S), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy analyses. SEM analysis of alkali-treated fibers showed an increase in roughness due to surface lignin and hemicellulose defibrillation. DSC analysis showed for all the samples an endothermic and an exothermic peak at 70–80 and 340–360 ̊C due to the loss of adsorbed/ absorbed water and to decomposition of α-cellulose, respectively. Alkali-treated fibers dis- played a second peak around 290 ̊C attributed to the degradation of hemicellulose. FTIR spectra of the studied fibers show similar bands with different intensities attributed to the main components of cellulose-based materials. Alkali-pretreated fibers demonstrated excel- lent dyeing ability for all the tested dyes. Dye absorption depends on the chemical fiber, dye structure, and concentration. The results of washing fastness are very good for all the tested fibers. The dyeing effluent treated with an advanced microfiltration method using an improved alumina ceramic membrane shows an average efficiency of 98% in turbidity and color reduction. Low-cost ceramic alumina microfiltration membranes are a very promising advanced treatment for textile industrial effluents allowing water reuse.C2011-UMINHO-2C2T-01 acknowledges the funding from Programa Compromisso para a Ciência 2008, Portugal
    corecore