•A new method that allows the effects of generator aging to be included in the reliability analysis of power systems is proposed.•A novel model for the failure rate capable of representing the stages ...of normal operation and wear-out is described.•Catastrophic failures and equipment refurbishing actions are also included in the proposed method.•The new method is built using a chronological Monte Carlo simulation and variance reduction techniques.•The aging of components can cause significant reductions in the reliability of generating systems.
Equipment aging has been a major concern among electric utilities’ planners, since quality of service can be put at risk. This paper proposes a new method that allows the effects of the aging of generators to be properly included into the reliability analysis of power systems. First, a new model for the failure rate capable of representing the stages of normal operation and wear-out, replacing the adoption of constant failure rates, is described. The effects of repairable and non-repairable (i.e., catastrophic) failures on the reliability assessment of generation systems are also discussed. The proposed method is built from the previous models using a sequential Monte Carlo simulation and variance reduction techniques. To validate the proposed method, the IEEE Reliability Test System is used with modifications in which different ages are defined for existing generating units that are progressively aging over the years. Several tests are described together with strategies for adopting preventive refurbishments and the corresponding results are duly discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The Joanes River is located in the northeast of Brazil, crosses the Camaçari Petrochemical Complex, the largest integrated industrial complex in the Southern Hemisphere, which has over 90 companies ...in the chemical and petrochemical industry. The present study aims to evaluate spatial distribution, seasonal variation and identify possible sources of trace metal contamination in surface water samples of the Joanes River. Samples were collected in the dry (December 2018) and rainy (August 2019) seasons. Analysis of trace elements (As, Cd, Cr, Cu, Ni, Mn and Pb) were performed by ICP-MS. A total of 60 water samples were obtained. Samples were analyzed using exploratory techniques such as principal component analysis (PCA) and cluster analysis (CA). It was possible to characterize the samples according to the seasonal variation. The formation of two groups was observed. Among these, samples from the rainy season presented the higher levels of metals in relation to the samples of the dry season. Natural and anthropic sources of metal contamination were identified using CA. Similarity was shown in the relationship between the metals As–Pb and Ni–Cd–Cr–Cu in the dry season, and Cd–Ni and Pb–As–Cr–Cu in the rainy season. Dermal absorption (HQderm) and ingestion hazard quotients (HQing) routes exhibited values of less than one for all the elements analyzed for adults and children, in both rainy and dry seasons. This indicated that the pollutants analyzed posed little or no health risk over a lifetime of exposure. According to international guidelines (US EPA), the values of Cu, Pb and Cr were above the limit established.
•First evaluation of trace metals pollution in Joanes River water were conducted.•In this region that concentrates the Brazil's largest industry complex.•The CA and PCA analyses were effective to identify the water pollution sources.•CA suggested that As, Cr, Cu, Cd, Ni and Pb were mainly anthropogenic sources.•As showed the highest values for HQing for adults in the dry and rainy periods.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract The objective of this study was to evaluate the stability of bite marks in foods in different conditions of time and temperature and their reliability as evidenced in criminal ...investigations. Sampling came from 20 subjects, who were instructed to bite five pieces of cheese and five pieces of chocolate. Bites were produced by the anterior teeth, from canine to canine, and the volunteers had their dental arches molded to obtain plaster models that were used for later comparison. The samples produced by each participant were stored and analyzed according to the temperature (room and refrigerator) and time period (immediately after, three days, seven days). The linear model with mixed effects using R Core Team and SAS Statistical Software were used for the statistical analysis. The results of this study reveal that the storage temperature of these materials does not exert a significant influence. Both chocolate and cheese showed better results when measurements were made shortly after, however the chocolate showed to be more stable in longer periods of time. By means of this study, it was possible to demonstrate that the storage temperature does not exert a significant influence. However, the bite marks found in foods with greater dimensional stability and short time intervals, are more reliable and allow their use as evidence in criminal investigations. Still, due to the limitations presented, we recommend its use for the exclusion of possible suspects and not for the suspects identification.
Resumo O objetivo deste estudo foi avaliar a estabilidade das marcas de mordida em alimentos em diferentes condições de tempo e temperatura e sua confiabilidade como evidência em investigações criminais. A amostragem foi composta por 20 indivíduos, que foram instruídos a morder cinco pedaços de queijo e cinco pedaços de chocolate. As mordidas foram produzidas pelos dentes anteriores, de canino a canino, e os sujeitos da pesquisa tiveram seus arcos dentais moldados para obter modelos que foram usados para posterior comparação. As amostras produzidas por cada participante foram armazenadas e analisadas de acordo com a temperatura (ambiente e geladeira) e período de tempo (imediatamente, após três dias e sete dias). Para a análise estatística, utilizou-se o modelo linear com efeitos mistos, utilizando R Core Team e SAS Statistical Software. Os resultados deste estudo revelam que a temperatura de armazenamento desses materiais não exerce influência significativa. Tanto o chocolate quanto o queijo apresentaram melhores resultados quando as mensurações foram feitas logo após, porém o chocolate mostrou-se mais estável em períodos mais longos. Por meio deste estudo, foi possível demonstrar que a temperatura de armazenamento não exerce influência significativa. Entretanto, as marcas de mordida encontradas em alimentos com maior estabilidade dimensional e intervalos de tempo curtos são mais confiáveis e permitem seu uso como evidência em investigações criminais. Ainda assim, devido às limitações apresentadas, recomendamos seu uso para a exclusão de possíveis suspeitos e não para a individualização dos mesmos.
Açaí,
Mart., is a native plant from the Amazonian and is rich in several phytochemicals with anti-tumor activities. The aim was to analyze the effects of açaí seed oil on colorectal adenocarcinoma ...(ADC) cells. In vitro analyses were performed on CACO-2, HCT-116, and HT-29 cell lines. The strains were treated with açaí seed oil for 24, 48, and 72 h, and cell viability, death, and morphology were analyzed. Molecular docking was performed to evaluate the interaction between the major compounds in açaí seed oil and Annexin A2. The viability assay showed the cytotoxic effect of the oil in colorectal adenocarcinoma cells. Acai seed oil induced increased apoptosis in CACO-2 and HCT-116 cells and interfered with the cell cycle. Western blotting showed an increased expression of LC3-B, suggestive of autophagy, and Annexin A2, an apoptosis regulatory protein. Molecular docking confirmed the interaction of major fatty acids with Annexin A2, suggesting a role of açaí seed oil in modulating Annexin A2 expression in these cancer cell lines. Our results suggest the anti-tumor potential of açaí seed oil in colorectal adenocarcinoma cells and contribute to the development of an active drug from a known natural product.
BACKGROUNDThe simultaneous administration of drugs with food can compromise the bioaccessibility and absorption of nutrients. The objective of this study was to evaluate the influence of the use of ...losartan potassium (LP), metformin hydrochloride (MH), and simvastatin (S) on the in vitro bioaccessibility of micronutrients (Cu, Fe, Mn, and Zn) in oat flour from Bahia, Brazil. METHODSThe experimental procedure consisted of the in vitro extraction of the bioaccessible fraction of Cu, Fe, Mn, and Zn in oat flour-with and without LP (50 mg), MH (500 mg), and S (20 mg)-using the unified bioaccessibility method (UBM), simulating the conditions of the gastrointestinal tract. For decomposition of the samples (oat flour and residue), a digester block with a closed system was used. To determine the total content (flour and residual fraction) and bioaccessible micronutrients, inductively coupled plasma optical emission spectrometry (ICP OES) was used. RESULTSThe bioaccessible contents (µg g-1) without the addition of drugs were: Cu 5.86 ± 0.21, Fe 32.80 ± 1.32, Mn 87.90 ± 1.90, and Zn 30.33 ± 2.05, with bioaccessibility ranging from 31.5 % for Fe to 99 % for Mn. The in vitro extraction method was validated by mass balance with recovery values from 89.78 % for Cu to 101.94 % for Mn. The range of bioaccessible contents (µg g-1) were: Cu (<4.14), Fe (32.10 ± 0.20-54.10 ± 2.03), Mn (81.40 ± 0.93-93.22 ± 0.80), and Zn (<10.80-29.11 ± 2.20). The estimation of the bioaccessibility of Cu, Mn, and Zn in oat flour were compromised in the presence of LP, MH, and S (p < 0.05). CONCLUSIONChemical interactions can occur between drugs and micronutrients. Taken together, our results highlight that LP, MH, and S can interfere with the bioaccessibility of Cu, Fe, Mn, and Zn in oat flour in patients who use these drugs, suggesting its rational use in further investigations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Resumo O objetivo deste artigo é avaliar a adequação do ganho de peso gestacional total (GPT) segundo características maternas de adolescentes brasileiras. Estudo transversal e de base hospitalar. ...Foram incluídos 3.904 adolescentes com gestação de feto único e idade gestacional (IG) ao nascimento ≥ 37 semanas. Foi construído um modelo hierarquizado para analisar as variáveis dependentes e a adequação do GPT e das independentes: características sociodemográficas, assistenciais, obstétricas e comportamentais. As chances de GPT insuficiente foram maiores para as adolescentes do Norte (OR = 1,50; IC95%: 1,07-2,10) e Nordeste (OR = 1,68; IC95%: 1,27-2,21). O trabalho remunerado elevou as chances de GPT insuficiente (IC95%: 1,15-2,39) e excessivo (IC95%: 1,01-1,86). O índice de massa corporal pré-gestacional de sobrepeso ou obesidade associou-se ao GPT excessivo (OR = 1,86; IC95%: 1,19-2,92 e OR = 3,06; IC95%: 2,10-4,45, respectivamente), bem como a IG ≥ 42 semanas (OR = 2,23; IC95%: 1,03-4,81). Residir nas regiões Norte e Nordeste aumentou as chances de as adolescentes apresentarem GPT insuficiente. Exercer trabalho remunerado esteve associado a maior chance de GPT excessivo e insuficiente. Além disso, o sobrepeso ou obesidade pré-gestacional e IG ≥ 42 semanas ampliaram as chances de GPT excessivo.
Abstract The scope of this article is to evaluate the adequacy of total gestational weight gain (GWG) according to maternal characteristics of Brazilian adolescents. It involved a cross-sectional, hospital-based study. A total of 3,904 teenagers with a single fetus gestation and gestational age (GA) at birth ≥ 37 weeks were included. A hierarchical model was built to analyze the dependent and independent variables adequacy of GWG: sociodemographic, care, obstetric and behavioral characteristics. The chances of insufficient GWG were higher for adolescents from the North (OR = 1.50, 95%CI: 1.07-2.10) and Northeast (OR = 1.68, 95%CI: 1.27-2.21). Paid work increased the chances of insufficient (95%CI: 1.15-2.39) and excessive (95%CI: 1.01-1.86) GWG. The pre-pregnancy body mass index of overweight or obese adolescents was associated with excessive GWG (OR = 1.86, 95%CI: 1.19-2.92 and OR = 3.06, 95%CI: 2.10-4.45, respectively), as well as GA ≥ 42 weeks (OR = 2.23, 95%CI: 1.03-4.81). Living in the North and Northeast regions increases the chances of adolescents having insufficient GWG. Having paid work was associated with a greater chance of excessive and insufficient GWG. Furthermore, pre-pregnancy excess weight or obesity and GA ≥ 42 weeks increased the chances of excessive GWG.
Omega-3 fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), offer numerous health benefits. Enriching these fatty acids in fish oil using cost-effective methods, like ...lipase application, has been studied extensively. This research aimed to investigate F. solani as a potential lipase producer and compare its efficacy in enhancing polyunsaturated omega-3 fatty acids with commercial lipases. Submerged fermentation with coconut oil yielded Lipase F2, showing remarkable activity (215.68 U/mL). Lipase F2 remained stable at pH 8.0 (activity: 93.84 U/mL) and active between 35 and 70 °C, with optimal stability at 35 °C. It exhibited resistance to various surfactants and ions, showing no cytotoxic activity in vitro, crucial for its application in the food and pharmaceutical industries. Lipase F2 efficiently enriched EPA and DHA in fish oil, reaching 22.1 mol% DHA and 23.8 mol% EPA. These results underscore the economic viability and efficacy of Lipase F2, a partially purified enzyme obtained using low-cost techniques, demonstrating remarkable stability and resistance to diverse conditions. Its performance was comparable to highly pure commercially available enzymes in omega-3 production. These findings highlight the potential of F. solani as a promising lipase source, offering opportunities for economically producing omega-3 and advancing biotechnological applications in the food and supplements industry.
Resumo Em 2008, Satoshi Nakamoto, pseudônimo de uma pessoa desconhecida, lançou o “Bitcoin”, uma criptomoeda descentralizada, com o objetivo de contornar qualquer banco ou governo e retornar a um ...sistema monetário mais “austero” e controlado. Após o advento do Bitcoin, várias outras criptomoedas foram criadas, suscitando um debate sobre a capacidade desses instrumentos substituírem o que atualmente usamos como “moeda”. Após 10 anos de sua criação, fica claro que o Bitcoin não atingiu o seu principal objetivo, mas levantou discussões importantes no âmbito das Autoridades Monetárias. Assim sendo, esse trabalho tem dois grandes objetivos. O primeiro é mostrar que, sob uma perspectiva teórica pós-keynesiana, o Bitcoin não fará frente às moedas fiduciárias, pois está muito mais próximo de ser um ativo especulativo altamente volátil do que uma moeda capaz de assumir as funções primordiais em uma economia capitalista. O segundo objetivo é apontar os desdobramentos dessa discussão no âmbito das Autoridades Monetárias, com destaque para as propostas das criptomoedas estatais.
Abstract In 2008, Satoshi Nakamoto, the pseudonym of an unknown person, launched ‘Bitcoin’, a decentralized cryptocurrency, aiming at circumventing banks or governments and returning to a more ‘austere’ and quantity-controlled monetary system. After Bitcoin, several other cryptocurrencies were created, and a debate on whether these instruments could ever replace what we currently use as ‘money’ surfaced. Ten years since its creation, it is clear that Bitcoin did not reach its main goal but raised important discussions within the framework of Monetary Authorities. Therefore, this work has two main objectives. The first is to show that, from a post-Keynesian theoretical perspective, Bitcoin cannot stand up to fiduciary currencies because it is much closer to being a highly volatile speculative asset than a currency capable of assuming the prime functions in a capitalist economy. The second objective is to point out the consequences of this discussion within the framework of the monetary authorities, with emphasis on the proposals of central bank cryptocurrencies.
This study aimed to investigate the acute effects of stretching exercise on skin temperature, flexibility, passive muscle stiffness, and pain during hamstring stretching in healthy young subjects. ...Thirty-one participants (n=31) were randomly divided into 2 groups: an experimental group (EG, n=15), which was submitted to hamstring stretching exercise for 180 sec, and the control group (n=16), which was not exercised. Skin tem-perature (TsK) was collected in subjects’ posterior thigh using a ther-mographic camera at 7 time points with intervals of 30 sec each: T0 (rest), T30, T60, T90, T120, T150, and T180. In addition, the knee range of motion, passive stiffness and muscle soreness (visual analogue scale) were recorded during the stretching procedure at the same times. The EG presented a small but progressive increase in TsK (30.8˚C±0.6˚C to 31.1˚C±0.6˚C, P<0.01), with an increased range of motion (P<0.01) and muscle soreness levels (P<0.01) during the gradual hamstring stretch-ing protocol. Additionally, there was an increment of passive stiffness (P<0.01) that was partially reversed toward the end of the stretching period. This research presents evidence that constant, passive and progressive stretching of the hamstrings progressively increased the local TsK by about 0.3˚C after 180 sec of stretching. These findings may help to understand the effects of repeated stress on the muscle-tendon unit and the role of muscle stretching in warm-up protocols and reha-bilitation.
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