Mitochondrial diseases impair oxidative phosphorylation and ATP production, while effective treatment is still lacking. Defective complex III is associated with a highly variable clinical spectrum. ...We show that pyocyanin, a bacterial redox cycler, can replace the redox functions of complex III, acting as an electron shunt. Sub-μM pyocyanin was harmless, restored respiration and increased ATP production in fibroblasts from five patients harboring pathogenic mutations in TTC19, BCS1L or LYRM7, involved in assembly/stabilization of complex III. Pyocyanin normalized the mitochondrial membrane potential, and mildly increased ROS production and biogenesis. These in vitro effects were confirmed in both Drosophila
and in Danio rerio
, as administration of low concentrations of pyocyanin significantly ameliorated movement proficiency. Importantly, daily administration of pyocyanin for two months was not toxic in control mice. Our results point to utilization of redox cyclers for therapy of complex III disorders.
Analyzing fat free mass (FFM) helps sport professionals during the prescription of sport training for children and adolescents in a sport initiation program. In this way, it is possible to determine ...fat mass (FM) (FFM subtracted from total body weight) and design interventions to increase FFM and reduce %F, making it possible to maximize performance in relation to the physical demands of sport. However, there is still no reliable anthropometric index to analyze FFM in this population. The aim the present study was to develop the Fat-Free Mass Index (FFMI) for pediatrics of both sexes.
Cross-sectional study with a sample composed of 254 pediatrics (139 males age: 13.0±2.3 and 115 females age: 12.5±2.2), from a sports initiation school. We divided the sample into the groups: 1) development (N.=169); and 2) cross-validation (N.=85). The body composition was analyzed by dual-energy X-ray absorptiometry (DXA), in addition we acquired anthropometric data (height, body weight and hip circumference) for the development of the FFMI - Pediatric (FFMIp). By means of linear regression we tested the predictive power of FFM using DXA as a reference method, then we developed FFMIp and tested its reliability and validity in relation to DXA.
FFMIp consisted of: -16.679 + (0.615 × body mass (kg)) - (2.601 × sex) + (0.618 × age(years)) - (0.332 × hip(cm)) + (0.278 × stature(cm)), where for sex 0 = male and 1 = female. For the FFM analysis, FFMIp showed no significant difference from DXA (P>0.05). It also showed significant accuracy (Cb>0.960), precision (ρ>0.990) and agreement (CCC>0.960) for both groups (development and cross-validation).
Pediatric FFMI proposed by this study proved to be valid for the analysis of fat-free mass in pediatric athletes of sports initiation of both sexes.
Objetivo: O mindset digital pode ser definido como um conjunto de comportamentos individuais relacionados ao grau de aderência às transformações digitais. Nesse contexto, o objetivo da presente ...pesquisa foi, após revisão de literatura sobre o tema, responder à seguinte questão: "É possível mensurar o mindset digital de profissionais por meio de uma escala elaborada para o contexto das organizações brasileiras?". Originalidade/valor: A digitalização das organizações passou a ser o centro da transformação dos negócios. No entanto, um dos fatores muitas vezes negligenciado no processo de transição é o desenvolvimento no nível micro-organizacional. Os profissionais variam no nível de interesse, no conhecimento e na capacidade de inovar. Para guiar o planejamento e desenvolvimento de uma cultura de aprendizagem digital, uma medida para identificar os perfis individuais de mindset digital seria essencial, mas tal ferramenta ainda não era encontrada na literatura brasileira. Design/metodologia/abordagem: A partir da literatura sobre estruturas cognitivas e a transformação digital, foi proposto um construto multidimensional de mindset digital. Elaboraram-se itens para a mensuração do grau de maturidade do construto, descrito por meio de três perfis digitais (open mind, transformador e empreendedor) e um analógico. A escala foi submetida a 574 profissionais de empresas brasileiras para análise fatorial exploratória. Resultados: A escala de mindset digital apresentou bons indícios de validade, sendo confirmadas, na presente amostra, as dimensões de mindset relacionadas ao meio digital (alfas de Cronbach entre 0,85 e 0,62).
•Mathematical model developed for pre-chamber torch ignition system design.•Experimental characterization with hydrous ethanol (PFI) and lean burn combustion.•Improved turbulent kinetic energy is ...generated by the pre-chamber.•Faster combustion process characterized by combustion analysis and visualization.•52% reduction of NOx emissions and improvements in ethanol conversion efficiency.
Energy is the key to wellbeing and sustainability of modern civilization and its demand continues to increase. With the end of oil availability perspectives and the world energy crisis, technological solutions are needed from the scientific community to promote the reduction of fossil fuel consumption, the maximization of fuel conversion efficiency and the reduction of emission levels in internal combustion engines. Aiming at reaching these needs, the use of a pre-chamber ignition system in spark-ignition (SI) engines is a potential alternative enabling such engines to operate with lean mixtures and with a wide variety of fuels. In this study, a methodology was developed to design and characterize experimentally a homogeneous charge pre-chamber torch ignition system fuelled with hydrous ethanol (with 6–7% in mass of water content) and using lean burn mixtures (excess air ratio (λ) > 1.0). The methodology, which has not been reported previously in other works, consisted of a one-dimensional mathematical model, that allowed for the definition of pre-chamber geometrical parameters. The device was manufactured and adapted to an SI engine, requiring no additional work to the cylinder head, as the pre-chamber was mounted in the original spark-plug screw thread. The prototype was experimentally characterized on an active dynamometer, and performance, combustion, emission and combustion visualization were studied. The pre-chamber ignition engine expanded the flammability limit in comparison with the baseline engine. For λ = 1.4, engine fuel conversion efficiency was increased by 5.4%, specific fuel consumption decreased by 22% and nitrogen oxides (NOx) emissions reduced by 52%, but total hydrocarbons (THC) emissions increased. Improvements achieved were due to the faster burn rates characterized by the reduced MBF 0–10%, combustion duration and combustion instability, and also the increased thermodynamic efficiency and the lower combustion temperatures achieved with lean burn technology. From the conclusions obtained in this research, the homogeneous pre-chamber torch ignition system developed for hydrous ethanol has potential for application and marketability integration, as an alternative technology able to help meet energy demands in a sustainable manner.
Mitochondria are organelles that are mainly involved in the generation of ATP by cellular respiration. In addition, they modulate several intracellular functions, ranging from cell proliferation and ...differentiation to cell death. Importantly, mitochondria are social and can interact with other organelles, such as the Endoplasmic Reticulum, lysosomes and peroxisomes. This symbiotic relationship gives advantages to both partners in regulating some of their functions related to several aspects of cell survival, metabolism, sensitivity to cell death and metastasis, which can all finally contribute to tumorigenesis. Moreover, growing evidence indicates that modulation of the length and/or numbers of these contacts, as well as of the distance between the two engaged organelles, impacts both on their function as well as on cellular signaling. In this review, we discuss recent advances in the field of contacts and communication between mitochondria and other intracellular organelles, focusing on how the tuning of mitochondrial function might impact on both the interaction with other organelles as well as on intracellular signaling in cancer development and progression, with a special focus on calcium signaling.
Most of the papers found in the literature concerned monitoring a process mean of a quality characteristic normally distributed. However, in several practical situations (like in reliability ...studies), the engineering team also desires to monitor a process mean in which the quality characteristic follows other probabilistic distributions, such as the Weibull. In this paper, we monitor a process mean of a random variable following a Weibull distribution using the traditional X¯$\overline{X}$ control chart. To improve the performance, Klein's two of two supplementary run rule is included in the X¯$\overline{X}$ chart. Such adoption promotes better performance, producing faster signals of abnormal situations (in terms of average run length) than the traditional X¯$\overline{X}$ chart in a great variety of shifts. An empirical example illustrates the proposed scheme.
This study examines the associations between perceived urban environment attributes and obesity indices by country using data from an eight-nation study from Latin America. The data were collected ...from 8185 adults. The Neighbourhood Environment Walkability-abbreviated scale was used to assess perceived urban environment attributes. Obesity indices considered were body mass index, waist circumference, neck circumference, a body shape index and waist-to-height ratio. The perception of a more and better land use mix-diversity (β - 0.44; 95% CI - 0.59, - 0.28), traffic safety (- 0.39; - 0.66, - 0.12), and safety from crime (- 0.36; - 0.57, - 0.15) was associated with lower body mass index across the entire sample. Land use mix-diversity (- 1.21; - 1.60, - 0.82), street connectivity (- 0.26; - 0.37, - 0.15), and traffic safety (- 0.79; - 1.47, - 0.12) were negatively associated with waist circumference. Land use mix-diversity (- 0.11; - 0.20, - 0.03), land use mix-access (- 0.23; - 0.34, 0.12), walking/cycling facilities (- 0.22; - 0.37, - 0.08), and safety from crime (- 0.27; - 0.42, - 0.12) were negatively associated with neck circumference. No associations between perceived urban environment attributes and a body shape index were found. Land use mix-diversity (- 0.01; - 0.02, - 0.01), aesthetics (- 0.02; - 0.03, - 0.01), and safety from crime (- 0.02; - 0.04, - 0.01) were associated with waist-to-height ratio. Environmental interventions involving urban environment attributes are associated with obesity indices and, therefore, may help decrease the prevalence of overweight and obesity.
•Dual-fuel led to better combustion phasing and lower CO and HC emissions.•Internal exhaust gas recirculation reduced pumping and heat transfer losses.•Increased efficiency with dual-fuel and ...internal exhaust gas recirculation.•NOx reductions of up to 70% were achieved.
This manuscript presents a deep analysis of natural gas-hydrous ethanol dual-fuel combustion in a spark ignition engine with a modified compression ratio and an advanced intake valve opening strategy to promote internal exhaust gas recirculation (iEGR). Both fuels were port-fuel injected and two different liquid fuel replacements by compressed natural gas (CNG) were tested (18 and 45% by energy). Combustion, performance and pollutant emissions were investigated under stoichiometric air-fuel conditions at 4 bar of net indicated mean effective pressure (IMEP) and 1800 rpm. Results show that dual-fuel mode improves fuel conversion efficiency when compared to CNG-only operation, due to lower carbon monoxide (CO) and unburnt hydrocarbons (HCs) emissions as well as to a better combustion phasing. The use of iEGR, despite deteriorating the combustion process as expected (ignition delay, combustion duration and combustion stability), improves efficiency because of a decrease in pumping losses and wall heat transfer, as well as pollutant emissions reduction. Nitrogen oxide (NOx) emissions increase with dual-fuel operation. However, the influence of iEGR was found to be more significant under dual-fuel mode than under single-fuel operation, with NOx reductions of up to 70% and fuel conversion efficiency improvements of around 2.5%.
The transportation sector faces a big energy challenge as it looks for more advanced technologies and renewable sources, in which pre-chamber ignition systems and bioethanol have gained worldwide ...recognition. In this manuscript, a homogenous torch ignition (HTI) system was experimentally analyzed in a commercial four-cylinder engine equipped with port-fuel injection and fueled with a gasoline-bioethanol blend with 25% of bioethanol by volume (E25). Tests were performed at a wide range of speeds and loads for stoichiometric and lean mixtures. Through in-cylinder pressure measurement, a combustion analysis was carefully carried out. Results show that the HTI system leads to a much faster combustion rate and low engine cycle-to-cycle variation due to enhanced ignition energy and turbulence levels in the main chamber, and is able to extend the lean combustion limit with acceptable combustion covariance up to λ = 1.30. Moreover, improved combustion phasing combined with reduced pumping losses and lower heat transfer to the cooling system decreased fuel consumption. BSFC was improved up to 8.4%, 12.1% and 10.2% for engine speeds of 2500, 3500 and 4500 rpm, respectively, for the 3.5 and 4.6 BMEP conditions at λ = 1.20, while the higher load (5.8 bar BMEP) was improved up to 8.6% at λ = 1.30.
•HTI system developed for a SI engine fueled with a gasoline-bioethanol blend.•Pre-chamber enhanced ignition energy and turbulence levels in the main chamber.•Lean limit operation extended to lambda of 1.30•BSFC improvements were up to 12.1%.
Resumo Fundamento O cardioversor-desfibrilador implantável (CDI) pode causar níveis elevados de ansiedade e depressão, resultando em efeitos negativos na qualidade de vida. Objetivos Avaliar a ...qualidade de vida, a ansiedade e a aceitação do CDI por meio de instrumentos de medida padronizados e identificar preditores de melhores respostas para cada um dos desfechos estudados. Método Coorte prospectiva com pacientes submetidos a implante inicial de CDI ou reoperação para a manutenção do dispositivo. Os desfechos do estudo incluíram: qualidade de vida, ansiedade e aceitação do CDI. A mudança nos escores (30 e 180 dias) foi avaliada por meio da diferença mínima importante (DMI). Foi utilizada a análise univariada e o modelo de regressão logística multivariada para a identificação de preditores de melhores respostas, adotando-se o nível de significância de 5%. Resultados De janeiro/2020 a junho/2021 foram incluídos 147 pacientes, com idade média de 55,3 ± 13,4 anos e predomínio do sexo masculino (72,1%). A DMI para qualidade de vida, a ansiedade e a aceitação do CDI foram observadas em 33 (22,4%), 36 (24,5%) e 43 (29,3%) pacientes, respectivamente. Idade igual ou maior que 60 anos (OR=2,5; IC 95%=1,14-5,53; p=0,022), ausência de fibrilação atrial (OR=3,8; IC 95%=1,26-11,63; p=0,017) e sexo feminino (OR=2,2; IC 95%=1,02-4,97; p=0,045) foram preditores independentes de melhores respostas para qualidade de vida, ansiedade e aceitação do CDI, respectivamente. Conclusão A identificação de preditores para melhores escores de qualidade de vida, ansiedade e aceitação do dispositivo pode subsidiar a implementação de cuidados específicos para os pacientes com maiores chances de apresentar resultados desfavoráveis.
Abstract Background An implantable cardioverter-defibrillator (ICD) can cause high levels of anxiety and depression, resulting in negative effects on quality of life. Objectives To evaluate the quality of life, anxiety, and acceptance of the ICD using standardized measurement instruments and identify predictors of better responses for each of the outcomes studied. Method This is a prospective cohort study with patients undergoing initial ICD implantation or reoperation to maintain the device. The study outcomes included quality of life, anxiety, and acceptance of the ICD. The change in scores (30 and 180 days) was assessed using the minimal important difference (MID). Univariate analysis and the multivariate logistic regression model were used to identify predictors of better responses, adopting a significance level of 5%. Results A total of 147 patients were included between January/2020 to June/2021, with a mean age of 55.3 ± 13.4 years and a predominance of males (72.1%). The MID for quality of life, anxiety, and ICD acceptance were observed in 33 (22.4%), 36 (24.5%) and 43 (29.3%) patients, respectively. Age equal to or greater than 60 years (OR=2.5; 95%CI=1.14-5.53; p=0.022), absence of atrial fibrillation (OR=3.8; 95%CI=1.26-11.63; p=0.017) and female gender (OR=2.2; 95%CI=1.02-4.97; p=0.045) were independent predictors of better responses to quality of life, anxiety and acceptance of the ICD, respectively. Conclusion The identification of predictors for better quality of life scores, anxiety, and acceptance of the device can support the implementation of specific care for patients with a greater chance of presenting unfavorable results.
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