Optimization of Self-Assembled Particle Deposition for Colloidal Lithography Nano/Micro-Patterning

Colloidal lithography (CL) is nowadays considered a preferential nano/micro-patterning method for photovoltaic structuring, as it is an inexpensive and highly scalable soft-lithography technique allowing nanoscale precision over indefinitely large areas. Photonic wavelength-sized structures are on the top of the list of solutions that can boost photovoltaic performance without significantly increasing cost, as they enable pronounced broadband anti-reflection, LT effects, and even self-cleaning functionality. In particular, recent research suggested that these micro-structures can boost not only the efficiency but also the stability of the emergent perovskite solar cell technology. CL methods critically depend on the long-range ordered self-assembly that can be attained upon deposition of the particles’ array used as a mask, which is performed via the Langmuir-Blodgett method. However, it is still challenging to achieve the desired deposition quality particularly with the preferential polystyrene colloids with wavelength-scale dimensions. This thesis is focused on tackling this challenge and in the optimization of the self-assembly deposition of polystyrene nanospheres monolayers onto flexible substrates, as a part of a full CL method for photonic-enhancement purposes in thin-film solar cells. In this work, we report a breakthrough in our Langmuir-Blodgett (LB) method which prevents wavelength-sized particles from sinking into the aqueous sub-phase and spontaneously form the desired close-packed hexagonal monolayer. This was attained by using sodium dodecyl sulfate (SDS) to reduce the aqueous sub-phase surface tension and hence improve the air-water interface stability of polystyrene spheres of various diameters. The addition of SDS, with best results at 4.5 mg/l concentration, showed remarkable improvement on the self-assembly step, by avoiding the nanospheres sinking and by producing uniform high-quality monolayer films. The quality of the deposition was also improved by controlling the LB barrier closing rate and increasing the self-assembly work area, which resulted in fully patterned flexible substrates.A litografia coloidal é atualmente vista como método preferencial para a micro e nanopadronização de estruturas fotónicas, já que se revela de baixo custo e com potencial de aplicação a largas escalas. As nanoestruturas fotónicas estão no topo da lista de soluções que podem assegurar uma melhoria significativa na eficiência fotovoltaica sem aumento do custo, permitindo efeitos de anti reflexão, captura de luz e até de autolimpeza. Estudos recentes sugerem que este tipo de microestruturas poderá não só beneficiar a eficiência dos dispositivos como melhorar a estabilidade da tecnologia emergente de células solares de perovskita. Esta técnica depende da área de automontagem ordenada que se obtém com a deposição de partículas coloidal como máscara, através de métodos como Langmuir-Blodgett. No entanto, revela-se difícil a deposição de partículas de poliestireno com dimensões da escala típica dos comprimentos de onda. Esta tese foca-se em ultrapassar este obstáculo e otimizar a deposição em substratos flexíveis, de modo a aplicar num método de litografia coloidal para o melhoramento fotónico de células solares de filme fino. No decurso deste trabalho, reportamos a otimização do nosso método Langmuir Blodgett (LB) de modo a prevenir que partículas mais pequenas se afundem, permitindo a formação de uma monocamada ordenada e com estrutura hexagonal, como desejado. Isto deve se à dissolução de dodecil sulfato de sódio (SDS) na subfase aquosa de modo a reduzir a sua tensão superficial, melhorando a estabilidade das esferas na interface ar-água. A adição de SDS, a uma melhor concentração de 4.5 mg/l, revelou melhorias significativas na automontagem, evitando o afundamento das nanoesferas e permitindo a produção de uma monocamada de elevada qualidade para a deposição. A qualidade da deposição foi também otimizada através do controlo do fecho de barreiras e do aumento da área dedicada à automontagem, resultando em substratos totalmente depositados

Dose-dependent protective and inductive effects of xanthohumol on oxidative DNA damage in Saccharomyces cerevisiae

The effect of xanthohumol, a prenylflavonoid isolated from the hop plant (Humulus lupulus L.), on Saccharomyces cerevisiae DNA oxidative damage and viability was evaluated. Yeast cultures under oxidative stress, induced by H2O2, displayed stronger growth in the presence of 5 mg/L of xanthohumol than cultures with only H2O2. Likewise, DNA damage assessed by the comet assay was significantly lower in cells co-incubated with xanthohu- mol and H2O2. Accordingly, fluorescence of dichlorofluorescein in cells treated with H2O2 and xanthohumol was considerably lower than in cells exclusively treated with H2O2, in- dicative of a reactive oxygen species scavenging mechanism and consequent formation of oxidation products, as detected by mass spectrometry. However, at concentrations above 5 mg/L, xanthohumol elicited an opposite effect, leading to a slower growth rate and signifi- cant increase in DNA damage. A yeast yap1 deletion mutant strain sensitive to oxidative stress grew more slowly in the presence of at least 5 mg/L of xanthohumol than cultures of the wild type, suggesting that xanthohumol toxicity is mediated by oxidative stress. This evidence provides further insight into the impact of xanthohumol on yeast cells, support- ing dose-dependent antioxidant/antigenotoxic and prooxidant/genotoxic effects.This work was funded by FEDER through the Operational Programme for Competitiveness Factors – COMPETE and by National Funds through FCT – Foundation for Science and Technology, under the projects UID/ QUI/50006/2013 and NORTE-07-0124-FEDER-000069. DC wishes to acknowledge FCT for his PhD studentship (SFRH/BD/79939/2011). BJ acknowledges the support of FCT through project PTDC/AAC-AMB/120940/2010 'MYCOFAT'. DC wishes to acknowledge FCT for his PhD studentship (SFRH/BD/79939/2011). We thank Martin Biendl, from Hopsteiner (New York, NY, USA), for donating the xanthohumol and Cristina Ribeiro for help in fl ow cytometry analyses. Mass spectrometry analyses were conducted at CEMUP (Materials Centre of the University of Porto, Portugal).info:eu-repo/semantics/publishedVersio

Modelagem para programação de navios e a otimização da utilização do canal do Porto de Santos

A gestão de um recurso de forma a se obter a máxima ocupação deste requer não somente a técnica de planejamento adequada, mas também a consideração das incertezas inerentes ao uso deste recurso. Este trabalho visa utilizar o ponto forte das duas principais vertentes da pesquisa operacional: a visão holística da otimização através da técnica de programação de produção aplicada a um sistema logístico portuário; e também a flexibilidade da simulação de eventos discretos, considerando as aleatoriedades do mesmo processo. Desta forma, a integração das duas vertentes abordadas neste trabalho fornece aos tomadores de decisão de sistemas portuários um modelo matemático que auxilia na obtenção de melhor ocupação de um canal de acesso aos terminais portuários. Assim, foi desenvolvido um modelo de otimização, inspirado no Job-Shop aplicado em um sistema logístico, capaz de analisar um conjunto de navios e um modelo simulação contemplando todas as etapas de um processo de descarregamento de um navio em um terminal portuário, incluindo a aleatoriedade de cada uma das etapas, disponibilidade de ativos, regras de cruzamento e movimentações no canal. Através desta modelagem híbrida, pretende-se obter uma avaliação realista da proposta gerada pelo otimizador utilizando indicadores como: ocupação do sistema, tempo em fila e tempo de estadia do navio

Análise do processo de conformidade das normas regulamentadoras em uma empresa de telecomunicações em Manaus / Analysis of the compliance process of regulatory standards in a telecommunications company in Manaus

Com a globalização dos mercados houve um aumento considerável da competitividade mundial, o que impõe às organizações a busca contínua de novas ferramentas de gestão como na área de saúde e segurança trabalho. Devido essa necessidade, o objetivo deste trabalho é analisar o atendimento as normas regulamentadoras relacionadas à Segurança e a Saúde no Trabalho em uma empresa do setor de telecomunicações, com a finalidade de reduzir os valores de possíveis multas pelo Ministério de Trabalho. A pesquisa foi classificada como exploratória e um estudo de caso. As fontes de dados necessárias para a realização do estudo foram: pesquisa em campo, bibliográfica e análise observacional direta. A abordagem utilizada foi quali-quantitativa para compreender todas as informações levantadas. Os dados foram obtidos por meio de check-list, abordando 21 NRs, com 646 itens cabíveis a empresa. Os resultados dos itens verificados, foram 140 conformes, 310 não conformes, e 196 não são aplicáveis a realidade da empresa. O resultado financeiro produzido por meio dos cálculos de multas estimou que a empresa pode pagar o valor total de R$846.975,56 em multa. Contudo, a infração 3 é a que mais representa problema a empresa de telecomunicação X, pois esta infração sozinha representa um risco potencial de multa podendo alcançar o teto máximo de R$ 464.466,94, ou seja, 54,84%. Considerar os critérios de urgência as infrações número 1 são as que mais representa risco a organização analisada, por isso são as que devem ser trabalhada de forma imediata a fim de reduzir os riscos potenciais de multa a ser pago. Para mitigar os itens não conformes das 21 NR’s analisada na empresa, propôs-se ações, apresentadas por um plano de ação 5W2H para as normas (NR-7, NR-9, NR-10, NR-15, NR-17, NR-33, NR-35) porque são as que mais influenciaram nos resultados da organização. Com isso espera-se reduzir os riscos potenciais de multa, melhorar a produtividade, a motivação e a satisfação, além da qualidade de vida dos indivíduos.

Brewer’s spent grains protects against oxidative DNA damage in Saccharomyces cerevisiae

Brewer’s spent grain (BSG), obtained from barley malt during brewing, contains high amounts of phenolic acids, predominantly ferulic and p-coumaric acids. The protective effects of BSG extracts against oxidative DNA damage induced by H2O2 in Saccharomyces cerevisiae cells were investigated using an optimized yeast comet assay and flow cytometry. The results indicated that BSG extracts from black malt exhibited a 5-fold reduction in the genotoxic effects of H2O2, compared to the 2-fold decrease by the BSG extracts from pilsen malts. Flow cytometry analysis with dichlorofluorescein diacetate demonstrated that the intracellular oxidation of S. cerevisiae is also reduced to approximately 50% in the presence of 20-fold diluted BSG extracts. BSG extracts obtained from pilsen and black malt types exert dose-dependent protective properties against the genotoxic effects induced by ROS and decrease intracellular oxidation of yeast cells.This work received financial support from the European Union (FEDER Funds through COMPETE) and National Funds (FCT, Fundação para a Ciência e a Tecnologia) through project Pest-C/EQB/LA0006/2013 and PEst-C/BIA/UI4050/2011. The work also received financial support from the European Union (FEDER funds) under the framework of QREN through Project NORTE-07-0124-FEDER-000069. DOC receives a postdoc grant through the project Operação Norte-01-0145-FEDER-000011. MMM wishes to acknowledge to FCT for her postdoctoral grant (SFRH/BPD/97049/2013). The authors also thank Unicer – Bebidas de Portugal, S. A. for the supply of BSG samples.info:eu-repo/semantics/publishedVersio

Nutritional Status among Portuguese and Turkish Older Adults Living in the Community: Relationships with Sociodemographic, Health and Anthropometric Characteristics

Malnutrition is widespread among older adults, and its determinants may differ between countries. We compared Portuguese and Turkish non-institutionalized older adults regarding nutritional status, sociodemographic, health and anthropometric characteristics and studied the relationships between nutritional status and those characteristics. This cross-sectional study analyzed data from 430 Portuguese and 162 Turkish non-institutionalized older adults regarding sociodemographics, health conditions, the Mini-Nutritional Assessment (MNA-FF) and anthropometry. Turkish older adults were more likely to be malnourished or at risk of malnutrition and had lower average BMI but a higher calf circumference. A higher proportion of the Portuguese sample had tooth loss, diabetes, hypertension, oncologic diseases, kidney diseases, osteoarticular problems or eye problems, while less had anemia. A better nutritional status (higher MNA-FF score) was found among the Portuguese, males, people using dentures, those without tooth loss, hypertension, cardiovascular diseases, anemia or oncological diseases and was related to younger age, higher BMI and a higher calf circumference. Malnutrition and its risk were higher among older adults from Turkey, despite Portuguese older adults presenting a higher prevalence of chronic diseases. Being female, older age, tooth loss, hypertension, anemia, CVD or oncological disorders and having a lower BMI or CC were associated with higher rates of malnutrition among older adults from Portugal and Turkey

Avaliação de hábitos alimentares numa população ucraniana residente em Portugal

[Resumo][Abstract

Evaluation of biotechnological processing through solid-state fermentation of oilseed cakes on extracts bioactive potential

Oilseed cakes (OC) are natural sources of lignocellulosic biomass, produced every year in large amounts. In addition to their main applications as animal feed, plant or soil fertilizer, and compost, they present enormous potential for being used in biotechnological processes for the obtainment and extraction of valuable bioactive compounds. This work evaluated the effect of solid-state fermentation on the bioactive properties of extracts obtained from the bioprocessing of OC and evaluated the effect of solvents on the recovery of compounds with higher bioactive potential. A general decrease of EC50 values was observed for fermented extracts obtained using a mixture of water/methanol (1:1) as extraction solvent. A decrease in the minimum inhibitory concentration was observed for fermented water extracts compared to non-fermented. Additionally, growth inhibition of Listeria monocytogenes was observed when using aqueous methanolic fermented extracts. These extracts also exhibited a higher percentage of growth reduction against phytopathogenic fungi, and some extracts exhibited increased protection against genotoxic agents such as camptothecin and bisphenol A. It was demonstrated that bioprocessing of OC through SSF is an effective approach to obtaining valuable compounds with bioactive properties for use in the food, pharmaceutical or cosmetic industries.Open access funding provided by FCT|FCCN (b-on). The authors thank the Portuguese Foundation for Sci ence and Technology (FCT) under the scope of the strategic funding of UIDB/BIO/04469/2020 and UIDB/04033/2020 units. Daniel Sousa acknowledges the fnancial support pro vided by national funds through FCT(PD/BD/135328/2017), under the Doctoral Program “Agricultural Production Chains – from fork to farm” (PD/00122/2012) and from the European Social Funds and the Regional Operational Programme Norte 2020.info:eu-repo/semantics/publishedVersio

Numerical investigation of the in-plane seismic performance of unstrengthened and TRM-strengthened rammed earth walls

The large availability of raw earth around the World led to its extensive use as a building material through history. Thus, earthen materials integrate several historical monuments, but their main use was to build living and working environments for billions of people. On the other hand, past earthquakes revealed their inadequate seismic behavior, which is a matter of concern as a significant percentage of earthen buildings are located in regions with medium to high seismic hazard. Nevertheless, their seismic behavior and the development of efficient strengthening solutions are topics that are not yet sufficiently investigated in the literature. In this context, this study investigates numerically the in-plane seismic behavior of a rammed earth component by means of advanced nonlinear finite element modeling, which included performing nonlinear static (pushover) and nonlinear dynamic analyses. Moreover, the strengthening effectiveness of a low-cost textile-reinforced mortar on such component was also evaluated. The strengthening was observed to increase the load and displacement capacities, to preserve the integrity for higher lateral load levels and to postpone failure without adding significant mass to the system. Furthermore, the pushover analysis was shown to predict reliably the capacities of the models with respect to the incremental dynamic analysis.This work was financed by FEDER funds through the Competitively Factors Operational Programme (COMPETE) and by national funds through the Foundation for Science and Technology (FCT) within the scope of projects POCI-01-0145-FEDER-016737 (PTDC/ECM-EST/2777/2014) and POCI-01-0145-FEDER-007633. The support from grant SFRH/BPD/97082/2013 is also acknowledged

A practical clinical score

Copyright © 2022 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.INTRODUCTION AND OBJECTIVES: Obstructive coronary artery disease (CAD) remains the most common etiology of heart failure with reduced ejection fraction (HFrEF). However, there is controversy whether invasive coronary angiography (ICA) should be used initially to exclude CAD in patients presenting with new-onset HFrEF of unknown etiology. Our study aimed to develop a clinical score to quantify the risk of obstructive CAD in these patients. METHODS: We performed a cross-sectional observational study of 452 consecutive patients presenting with new-onset HFrEF of unknown etiology undergoing elective ICA in one academic center, between January 2005 and December 2019. Independent predictors for obstructive CAD were identified. A risk score was developed using multivariate logistic regression of designated variables. The accuracy and discriminative power of the predictive model were assessed. RESULTS: A total of 109 patients (24.1%) presented obstructive CAD. Six independent predictors were identified and included in the score: male gender (2 points), diabetes (1 point), dyslipidemia (1 point), smoking (1 point), peripheral arterial disease (1 point), and regional wall motion abnormalities (3 points). Patients with a score ≤3 had less than 15% predicted probability of obstructive CAD. Our score showed good discriminative power (C-statistic 0.872; 95% CI 0.834-0.909: p<0.001) and calibration (p=0.333 from the goodness-of-fit test). CONCLUSIONS: A simple clinical score showed the ability to predict the risk of obstructive CAD in patients presenting with new-onset HFrEF of unknown etiology and may guide the clinician in selecting the most appropriate diagnostic modality for the assessment of obstructive CAD.proofepub_ahead_of_prin