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SMA actuators are a group of lightweight actuators that offer advantages over conventional technology and allow for simple and compact solutions to the increasing demand for electrical actuation. In particular, an increasing number of SMA torsional actuator applications have been published recently due to their ability to supply rotational motion under load, resulting in advantages such as module simplification and the reduction of overall product weight. This paper presents the conceptual design, operating principle, experimental characterization and working performance of torsional actuators applicable in active rudder in aeronautics. The proposed application comprises a pair of SMA torsion springs, which bi-directionally actuate the actuator by Joule heating and natural cooling. The experimental results confirm the functionality of the torsion springs actuated device and show the rotation angle of the developed active rudder was about 30° at a heating current of 5 A. After the design and experiment, one of their chief drawbacks is their relatively slow operating speed in rudder positioning, but this can be improved by control strategy and small modifications to the actuator mechanism described in this work.

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The risk of the use of toxic chemicals for unlawful acts has been a matter of concern for different governments and multilateral agencies. The Organisation for the Prohibition of Chemical Weapons (OPCW), which oversees the implementation of the Chemical Weapons Convention (CWC), considering recent events employing chemical warfare agents as means of assassination, has recently included in the CWC "Annex on Chemicals" some organophosphorus compounds that are regarded as acting in a similar fashion to the classical G- and V-series of nerve agents, inhibiting the pivotal enzyme acetylcholinesterase. Therefore, knowledge of the activity of the pyridinium oximes, the sole class of clinically available acetylcholinesterase reactivators to date, is plainly justified. In this paper, continuing our research efforts in medicinal chemistry on this class of toxic chemicals, we synthesized an A-230 nerve agent surrogate and applied a modified Ellman's assay to evaluate its ability to inhibit our enzymatic model, acetylcholinesterase from Electrophorus eel, and if the clinically available antidotes are able to rescue the enzyme activity for the purpose of relating the findings to the previously disclosed in silico data for the authentic nerve agent and other studies with similar A-series surrogates. Our experimental data indicates that pralidoxime is the most efficient compound for reactivating acetylcholinesterase inhibited by A-230 surrogate, which is the opposite of the in silico data previously disclosed.

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The lack of synthesized information regarding biodiversity is a major problem among researchers, leading to a pervasive cycle where ecologists make field campaigns to collect information that already exists and yet has not been made available for a broader audience. This problem leads to long-lasting effects in public policies such as spending money multiple times to conduct similar studies in the same area. We aim to identify this knowledge gap by synthesizing information available regarding two Brazilian long-term biodiversity programs and the metadata generated by them. Using a unique dataset containing 1904 metadata, we identified patterns of metadata distribution and intensity of research conducted in Brazil, as well as where we should concentrate research efforts in the next decades. We found that the majority of metadata were about vertebrates, followed by plants, invertebrates, and fungi. Caatinga was the biome with least metadata, and that there's still a lack of information regarding all biomes in Brazil, with none of them being sufficiently sampled. We hope that these results will have implications for broader conservation and management guiding, as well as to funding allocation programs.

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OBJECTIVE: Our study aimed to revaluate the significant data from meta-analyses on genetic variations in immune mediators and the risk of prostate cancer (PCa) by Bayesian approaches. METHODS: We performed a search on the literature before September 5th, 2023, for meta-analytic studies on polymorphisms in immune mediator genes and the risk of PCa. Two Bayesian approaches were used to assess the level of noteworthiness in the meta-analytic data: the False-Positive Rate Probability (FPRP) and the Bayesian False Discovery Probability (BFDP) with a statistical power of 1.2 and 1.5 of Odds Ratio at a prior probability of 10-3 and 10-6. The quality evaluation of studies was performed with the Venice criteria. Gene-gene and protein-protein networks were designed for the genes and products enrolled in the results. RESULTS: As results, 18 meta-analyses on 17 polymorphisms in several immune mediator genes were included (IL1B rs16944/rs1143627, IL4 rs2243250/rs2227284/rs2070874, IL6 1800795/rs1800796/rs1800797, IL8 rs4073, IL10 rs1800896/rs1800871/rs1800872, IL18 rs1946518, COX2 rs2745557, TNFA rs361525 and PTGS2 rs20417/689470). The Bayesian calculations showed the rs1143627 and the rs1946518 polymorphisms in IL1B and IL18 genes, respectively, were noteworthy. The Venice criteria showed that only four studies received the highest level of evidence. The gene-gene and protein-protein networks reinforced the findings on IL1B and IL18 genes. CONCLUSION: In conclusion, this current Bayesian revaluation showed that the rs1143627 and the rs1946518 polymorphisms in the IL1B and IL18 genes, respectively, were noteworthy biomarker candidates for PCa risk.

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OBJECTIVE: to investigate the contributions of applying the Lean methodology to improve work processes in health and nursing and its impact on associated financial aspects. METHOD: an integrative review, carried out in six databases, whose sample of ten (100.0%) studies was analyzed and summarized descriptively. RESULTS: the outcomes obtained were stratified into: benefits/barriers to Lean Healthcare implementation; economic aspects involving Lean Healthcare implementation; and process improvements through Lean Healthcare implementation. The majority of studies (60.0%) were carried out in university hospitals, contexts that need to continually improve the quality of services provided, generally with scarce and limited resources, which support the viability of maintaining the teaching, research and extension tripod. CONCLUSION: three (30.0%) studies highlighted the financial aspects associated with Lean methodology application. The others only mentioned the possibility of financial gains through improving processes and reducing waste.

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In this paper, we use a Bayesian method to estimate the effective reproduction number ( R ( t ) ), in the context of monitoring the time evolution of the COVID-19 pandemic in Brazil at different geographic levels. The focus of this study is to investigate the similarities between the trends in the evolution of such indicators at different subnational levels with the trends observed nationally. The underlying question addressed is whether national surveillance of such variables is enough to provide a picture of the epidemic evolution in the country or if it may hide important localized trends. This is particularly relevant in the scenario where health authorities use information obtained from such indicators in the design of non-pharmaceutical intervention policies to control the epidemic. A comparison between R ( t ) estimates and the moving average (MA) of daily reported infections is also presented, which is another commonly monitored variable. The analysis carried out in this paper is based on the data of confirmed infected cases provided by a public repository. The correlations between the time series of R ( t ) and MA in different geographic levels are assessed. Comparing national with subnational trends, higher degrees of correlation are found for the time series of R ( t ) estimates, compared to the MA time series. Nevertheless, differences between national and subnational trends are observed for both indicators, suggesting that local epidemiological surveillance would be more suitable as an input to the design of non-pharmaceutical intervention policies in Brazil, particularly for the least populated states.

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Introduction: The human umbilical artery (HUA), rat-isolated right atrium, and rat-isolated vas deferens present a basal release of 6-nitrodopamine (6-ND). The basal release of 6-ND from these tissues was significantly decreased (but not abolished) when the tissues were pre-incubated with Nω-nitro-L-arginine methyl ester (L-NAME). Methods: In this study, the effect of the pharmacological modulation of the redox environment on the basal release of 6-ND was investigated. The basal release of 6-ND was measured using Liquid chromatography with tandem mass spectrometry (LC-MS/MS). Results and Discussion: Pre-incubation (30 min) of the tissues with GKT137831 (1 µM) caused a significant increase in the basal release of 6-ND from all tissues. In the HUA, pre-incubation with diphenyleneiodonium (DPI) (100 µM) also caused significant increases in the basal release of 6-ND. Preincubation of the HUA with hydrogen peroxide (H2O2) (100 µM) increased 6-ND basal release, whereas pre-incubation with catalase (1,000 U/mL) significantly decreased it. Pre-incubation of the HUA with superoxide dismutase (SOD) (250 U/mL; 30 min) also significantly increased the basal release of 6-ND. Preincubation of the HUA with either allopurinol (100 µM) or uric acid (1 mM) had no effect on the basal release of 6-ND. Pre-treatment of the HUA with L-NAME (100 µM) prevented the increase in the basal release of 6-ND induced by GKT137831, diphenyleneiodonium, and H2O2. The results obtained indicate a major role of endogenous H2O2 and peroxidases as modulators of 6- ND biosynthesis/release and a lack of peroxynitrite contribution.

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The aim of this work is to analyze the effect of water absorption on the mechanical properties and damage mechanisms of polyester/glass fiber/jute fiber hybrid composites obtained using the compression molding and vacuum-assisted resin transfer molding (VARTM) techniques with different stacking sequences. For this purpose, the mechanical behavior under tensile stress of the samples was evaluated before and after hygrothermal aging at different temperatures: TA, 50 °C, and 70 °C for a period of 696 h. The damage mechanism after the mechanical tests was evaluated using SEM analysis. The results showed a tendency for the mechanical properties of the composites to decrease with exposure to an aqueous ambient, regardless of the molding technique used to conform the composites. It was also observed that the stacking sequence had no significant influence on the dry composites. However, exposure to the aqueous ambient led to a reduction in mechanical properties, both for the molding technique and the stacking sequence. Damage such as delamination, fiber pull-out, fiber/matrix detachment, voids, and matrix removal were observed in the composites in the SEM analyses.

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In this study, we comprehensively investigated the degradation of industrial trinitrotoluene (TNT), focusing on the effects of aging and direct contact with steel surfaces, mirroring real-world usage conditions. While practical knowledge exists regarding this degradation, the existing literature lacks in-depth insights into the underlying processes. To address this gap, we conducted experiments using small steel samples, representative of military ammunition casings, which were coated with TNT and subjected to 30 days of heating at 75 °C under vacuum conditions. A subset of these samples was coated with a protective red alkyd paint. After the aging process, the TNT was carefully removed from the metal surfaces and subjected to a comprehensive analysis encompassing scanning electron microscopy, Fourier-transform infrared spectroscopy, and gas chromatography-mass spectrometry. Our results reveal a remarkable preservation of the chemical integrity of industrial TNT, even in the presence of thermal stress and direct steel contact. Although superficial changes were observed in the TNT's appearance, all analytical data consistently demonstrated the maintenance of its chemical composition. Notably, the sole change in composition was attributed to the presence of degradation products associated with the alkyd paint coating, rather than intrinsic TNT degradation. These findings underscore the negligible impact of degradation processes on TNT in scenarios involving the solid-phase thermal stress of TNT in direct contact with metal, significantly enhancing our understanding of TNT safety when packaged within steel artifacts-a common context in military ammunition.

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OBJETIVO: Este estudo teve como objetivo propor um modelo cognitivo/explicativo que represente as mudanças que podem ser incorporadas à vida de jovens de baixa renda, a partir de sua primeira experiência de emprego formal. MÉTODO: A amostra do estudo foi composta por 25 jovens beneficiários do Programa Primeiro Emprego/BA, que participaram de grupos focais on-line. Para a análise, as falas foram inicialmente categorizadas por meio da análise de conteúdo temática e, em seguida, visando uma sistematização e o estabelecimento de uma relação entre as categorias adotadas, foi utilizada a técnica do mapeamento cognitivo. RESULTADOS: A partir da análise das falas dos jovens, foram identificados 29 núcleos de sentidos, distribuídos em torno da tríade indivíduo- trabalho-sociedade. Entre as mudanças pessoais percebidas, destacam-se a valorização e o crescimento pessoal, assim como questões financeiras. Nas mudanças laborais, o aumento da empregabilidade como resultado da maior qualificação profissional e das novas habilidades técnicas adquiridas foi amplamente citado. Por fim, no que diz respeito às mudanças sociais, a percepção de alteração do status social ficou evidente. A maioria das mudanças observadas foram positivas e indicaram um aumento na qualidade de vida dos jovens de baixa renda. CONCLUSÃO: Conclui-se, portanto, que para uma modificação dos padrões de reprodução da força de trabalho juvenil, baseados na precarização e na subalternidade, é necessária uma transformação da realidade laboral dos seus atores.

OBJECTIVE: This study aimed to propose a cognitive/explanatory model that represents the changes that can be incorporated into the lives of low-income young people, from their first experience of formal employment. METHOD: The study sample consisted of 25 young beneficiaries of the First Employment Program/ BA, who participated in online focus groups. For the analysis, the speeches were initially categorized through thematic content analysis and, then, aiming at systematization and the establishment of a relationship between the adopted categories, the cognitive mapping technique was used. RESULTS: Based on the analysis of the young people's statements, 29 nuclei of meanings were identified, and distributed around the individual-work-society triad. Among the perceived personal changes, valorization and personal growth stand out, as well as financial issues. In terms of job changes, the increase in employability as a result of higher professional qualifications and new technical skills acquired was widely cited. Finally, with regard to social changes, the perception of change in social status was evident. Most of the changes observed were positive and indicated an increase in the quality of life of low-income youth. CONCLUSION: It is concluded, therefore, that for a change in the system, a transformation of the work reality of its actors is necessary.

OBJETIVO: Este estudio tuvo como objetivo proponer un modelo cognitivo/explicativo que represente los cambios que pueden incorporarse en la vida de jóvenes de bajos ingresos, a partir de su primera experiencia de empleo formal. MÉTODO: La muestra del estudio estuvo compuesta por 25 jóvenes beneficiarios del Programa Primeiro Emprego/BA, que participaron de grupos focales en línea. Para el análisis, los enunciados fueron inicialmente categorizados a través del análisis de contenido temático y luego, con el objetivo de sistematizar y establecer una relación entre las categorías adoptadas se utilizó la técnica del mapeo cognitivo. RESULTADOS: A partir del análisis de los enunciados de los jóvenes, se identificaron 29 centros de significado, distribuidos en torno a la tríada individuo-trabajo-sociedad. Entre los cambios personales percibidos se destacan la apreciación y el crecimiento personal, así como las cuestiones financieras. En los cambios laborales se citó ampliamente el aumento de la empleabilidad como consecuencia de una mayor cualificación profesional y de nuevas competencias técnicas adquiridas. Finalmente, en lo que respecta a los cambios sociales, se hizo evidente la percepción de cambios en el estatus social. La mayoría de los cambios observados fueron positivos e indicaron un aumento en la calidad de vida de los jóvenes de bajos ingresos. CONCLUSIÓN: Se concluye, por tanto, que para modificar los patrones de reproducción de la fuerza laboral juvenil, basados en la precariedad y la subalternidad, es necesaria una transformación de la realidad laboral de sus actores.

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