Sequential deposition method of TiO2/CH3NH3PbI3 films for solar cell application

Seeking to study innovative solar cell compositions with the goal to reach the highest energy efficiency level attainable, the aim of this study was to develop a route to obtain a solar cell composed by hybrid perovskite (CH3NH3PbI3) using a sequential deposition method through the techniques of spin-coating and immersion. Initially, the deposition of PbI2 thin film of was performed on a FTO/glass substrate coated with TiO2, which was subsequently converted into perovskite crystals through spin coating using a CH3NH3I solution. The influence of the PbI2 layer thickness on the formation of CH3NH3PbI3 crystals was evaluated. The hydrophilic characteristic of TiO2 affects the distribution of the crystals nucleation sites, since PbI2 possesses a non-polar liquid characteristic. The characterization of the perovskite thin films showed that thickness affects directly the bandgap and the surface morphology, revealing the presence of dendritic structures and acicular crystals. Both growth and coverage increased for thinner layers of PbI2. It was also possible to observe an increased uniformity in the film for smaller PbI2 layers

Super rogue wave generation in the linear regime

Extreme or rogue waves are large and unexpected waves appearing with higher probability than predicted by Gaussian statistics. Although their formation is explained by both linear and nonlinear wave propagation, nonlinearity has been considered a necessary ingredient to generate super rogue waves, i.e., an enhanced wave amplification, where the wave amplitudes exceed by far those of ordinary rogue waves. Here we show, experimentally and theoretically, that optical super rogue waves emerge in the simple case of linear light diffraction in one transverse dimension. The underlying physics is a long-range correlation on the random initial phases of the light waves. When subgroups of random phases appear recurrently along the spatial phase distribution, a more ordered phase structure greatly increases the probability of constructive interference to generate super rogue events (non-Gaussian statistics with superlong tails). Our results consist in a significant advance in the understanding of extreme waves formation by linear superposition of random waves, with applications in a large variety of wave systems

Systems chemo-biology analysis of DNA damage response and cell cycle effects induced by coal exposure

Cell cycle alterations are among the principle hallmarks of cancer. Consequently, the study of cell cycle regulators has emerged as an important topic in cancer research, particularly in relation to environmental exposure. Particulate matter and coal dust around coal mines have the potential to induce cell cycle alterations. Therefore, in the present study, we performed chemical analyses to identify the main compounds present in two mineral coal samples from Colombian mines and performed systems chemo-biology analysis to elucidate the interactions between these chemical compounds and proteins associated with the cell cycle. Our results highlight the role of oxidative stress generated by the exposure to the residues of coal extraction, such as major inorganic oxides (MIOs), inorganic elements (IEs) and polycyclic aromatic hydrocarbons (PAH) on DNA damage and alterations in the progression of the cell cycle (blockage and/or delay), as well as structural dysfunction in several proteins. In particular, IEs such as Cr, Ni, and S and PAHs such as benzo[a]pyrene may have influential roles in the regulation of the cell cycle through DNA damage and oxidative stress. In this process, cyclins, cyclin-dependent kinases, zinc finger proteins such as TP53, and protein kinases may play a central role

Relação entre estresse oxidativo e componentes não-térmicos de campos eletromagnéticos no cérebro de ratos

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Association between serum lactate levels and mortality in patients with cardiogenic shock receiving mechanical circulatory support : a multicenter retrospective cohort study

Background: To evaluate the prognostic value of peak serum lactate and lactate clearance at several time points in cardiogenic shock treated with temporary mechanical circulatory support (MCS) using veno-arterial extracorporeal membrane oxygenation (VA-ECMO) or Impella CP®. Methods: Serum lactate and clearance were measured before MCS and at 1 h, 6 h, 12 h, and 24 h post-MCS in 43 patients at four tertiary-care centers in Southern Brazil. Prognostic value was assessed by univariable and multivariable analysis and receiver operating characteristic (ROC) curves for 30-day mortality. Results: VA-ECMO was the most common MCS modality (58%). Serum lactate levels at all time points and lactate clearance after 6 h were associated with mortality on unadjusted and adjusted analyses. Lactate levels were higher in non-survivors at 6 h, 12 h, and 24 h after MCS. Serum lactate >1.55 mmol/L at 24 h was the best single prognostic marker of 30-day mortality [area under the ROC curve=0.81 (0.67–0.94); positive predictive value=86%). Failure to improve serum lactate after 24 h was associated with 100% mortality. Conclusions: Serum lactate was an important prognostic biomarker in cardiogenic shock treated with temporary MCS. Serum lactate and lactate clearance at 24 h were the strongest independent predictors of short-term survival

Carnitina livre e aminoácidos de cadeia ramificada não são bons biomarcadores na doença de Huntington

Background: Huntington’s disease (HD), caused by an expanded CAG repeat at HTT, has no treatment, and biomarkers are needed for future clinical trials. Objective: The objective of this study was to verify if free carnitine and branched chain amino acids levels behave as potential biomarkers in HD. Methods: Symptomatic and asymptomatic HD carriers and controls were recruited. Age, sex, body mass index (BMI), age of onset, disease duration, UHDRS scores, and expanded CAG tract were obtained; valine, leucine, isoleucine, and free carnitine were measured. Baseline and longitudinal analysis were performed. Results: Seventy-four symptomatic carriers, 20 asymptomatic carriers, and 22 non-carriers were included. At baseline, valine levels were reduced in symptomatic and asymptomatic HD carriers when compared to non-carriers. No difference in free carnitine or isoleucine+leucine levels were observed between groups. BMI of symptomatic individuals was lower than those of non-carriers. Valine levels correlated with BMI. Follow-up evaluation was performed in 43 symptomatic individuals. UHDRS total motor score increased 4.8 points/year on average. No significant reductions in BMI or valine were observed, whereas free carnitine and isoleucine+leucine levels increased. Conclusions: Although valine levels were lower in HD carriers and were related to BMI losses observed in pre-symptomatic individuals, none of these metabolites seem to be biomarkers for HD.Introdução: A doença de Huntington (DH), causada por uma repetição CAG expandida no HTT, não possui tratamento e biomarcadores são necessários para futuros ensaios clínicos. Objetivo: Nosso objetivo foi verificar se os níveis de carnitina livre e aminoácidos de cadeia ramificada se comportam como potenciais biomarcadores na DH. Métodos: Portadores sintomáticos e assintomáticos e controles foram recrutados. Idade, sexo, índice de massa corporal (IMC), idade de início, duração da doença, escores UHDRS e trato CAG expandido foram obtidos; valina, leucina, isoleucina e carnitina livre foram medidas. Foram realizadas análises basal e longitudinal. Resultados: Setenta e quatro portadores sintomáticos, 20 portadores assintomáticos e 22 não portadores foram incluídos. No início do estudo, os níveis de valina estavam reduzidos em portadores de DH sintomáticos e assintomáticos quando comparados aos não portadores. Não foram observadas diferenças nos níveis de carnitina livre ou isoleucina + leucina entre os grupos. O IMC dos indivíduos sintomáticos foi menor que o dos não portadores. Níveis de valina correlacionaram-se com o IMC. Avaliação de acompanhamento foi realizada em 43 indivíduos sintomáticos. A pontuação do escore motor total da UHDRS aumentou 4,8 pontos/ano em média. Não foram observadas reduções significativas no IMC ou na valina, enquanto os níveis de carnitina livre e isoleucina+leucina aumentaram. Conclusões: Embora os níveis de valina tenham sido menores nos portadores de DH e estivessem relacionados às perdas de IMC observadas em indivíduos pré-sintomáticos, nenhum desses metabólitos parece ser biomarcador para a DH

Caracterização físico-química e avaliação e sensorial de cerveja pilsen produzida a partir de mandioca (Manihot esculenta Crantz., 1766) submetida a diferentes adubações de solo / Physico-chemical characterization and sensorial evaluation of pilsen beer produced from cassava (Manihot esculenta Crantz., 1766) submitted to different soil fertilizations

A proposta implantada teve como prospecção a utilização de subprodutos da mandioca (Manihot esculenta Crantz., 1766) tais como a polpa e a fécula produzidas a partir de diferentes plantios para produção de um produto (cerveja pilsen) com a intenção de baratear o custo da cerveja no mercado amazonense, pois o cultivo da mandioca é uma das principais atividades econômica do estado. Foram desenvolvidas 3 formulações da cerveja de mandioca, nas quais a mandioca foi submetida a diferentes concentrações de fósforo e potássio. Foram realizadas análises físico-químicas, onde se obteve valores de umidade, lipídios, proteínas e carboidratos de 3 tratamentos da mandioca. Foram realizadas análises físico-químicas das cervejas, onde se obteve valores de extrato real, acidez total, açúcares redutores totais, teor alcoólico, densidade, turbidez, pH, sólidos solúveis, °Brix e cor de 4 tratamentos de cerveja de mandioca. Os resultados da análise sensorial das cervejas de mandioca do tipo pilsen produzidas a partir de diferentes adubações da mandioca foram: aparência, cor, textura e sabor. O emprego de mandioca como adjunto foi uma alternativa viável para a diminuição de custos na preparação desde que não se ultrapasse a quantidade máxima estabelecida pela legislação brasileira que é aproximadamente 40% de adjunto