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1.
RSC Adv ; 14(22): 15220-15231, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38737968

RESUMO

The microstructure and physical properties of reflective and black aluminum were compared for layers of different thicknesses deposited by magnetron sputtering on fused silica substrates. Reflective Al layers followed the Volmer-Weber growth mechanism classically observed for polycrystalline metal films. On the contrary, the extra nitrogen gas used to deposit the black aluminum layers modified the growth mechanism and changed the film morphologies. Nitrogen cumulated in the grain boundaries, favoring the pinning effect and stopping crystallite growth. High defect concentration, especially vacancies, led to strong columnar growth. Properties reported for black aluminum tend to be promising for sensors and emissivity applications.

3.
Physiol Behav ; 254: 113908, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35817124

RESUMO

Acute mental stress (AMS) increases heart rate (HR) and blood pressure. Since obesity can impair the cardiovascular reactivity to AMS, a better understanding of the mechanisms involved in this response is needed. We aimed to evaluate the cardiovascular reactivity to AMS in young men with normal or excess body fat. We also assessed the association between cardiovascular reactivity to AMS and cardiovascular risk factors, including autonomic modulation, carotid artery distensibility, physical activity levels, and sleep efficiency. Sixty-six young men (26.1 ± 4.1 years old) underwent anthropometric and body fat assessment (dual-energy X-ray absorptiometry) and had right-carotid artery ultrasonography. Accelerometers assessed physical activity levels and sleep efficiency. AMS was induced through the Stroop color-word test while blood pressure, HR, and cardiac interval were measured. Analyses were performed in Normal and Excess fat groups divided by fat mass index (FMI). Continuous data was used for multiple linear regression analyses. An interaction between FMI and time for HR reactivity was observed. Cardiac interval variability analysis showed that only participants with normal fat displayed parasympathetic withdrawal during AMS (P < 0.05). Multiple linear regression analysis supported the role of adiposity and autonomic modulation in the HR reactivity to AMS and showed involvement of carotid distensibility and sleep efficiency (P < 0.05). Carotid distensibility was the only predictor for blood pressure reactivity (P < 0.05). Physical activity was not associated with AMS's cardiovascular reactivity. We conclude that increased adiposity is associated with reduced HR reactivity to AMS, which is possibly linked to an impaired parasympathetic withdrawal. Carotid distension and sleep efficiency seem to contribute to this response.


Assuntos
Adiposidade , Artérias Carótidas , Adulto , Frequência Cardíaca/fisiologia , Humanos , Masculino , Obesidade/diagnóstico por imagem , Sono , Adulto Jovem
4.
Sports Med Health Sci ; 4(2): 127-132, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35574287

RESUMO

This study aimed to describe yoga practice and verify its association with depression, anxiety, and stress during the COVID-19 pandemic among Brazilian practitioners. A cross-sectional anonymous online survey was conducted in all regions of Brazil using a snowball sampling strategy among yoga practitioners. A total of 860 participants (87% female, aged: 19-82 years) completed the survey. Sociodemographic data, lifestyle factors, yoga practice during the pandemic, and the Depression Anxiety and Stress Scale (DASS-21) scores were collected between July 9 and July 15, 2021. Overall, 9.5%, 9.3%, and 5.6% of participants exhibited some traits (mild to severe) of depression, anxiety, and stress, respectively. Hatha yoga (48%) was the most commonly practiced yoga style. In the adjusted analysis, a higher yoga experience (> 5 years) was associated with better anxiety (odds ratio; bootstrap 95% confidence interval: 2.42; 1.32, 4.49) and stress status (1.80; 1.06, 3.00) than beginners (< 1 year). Practitioners who reported higher time and days of yoga practice during the study period were more likely to show normal levels of depression (odds ratio: 2.56-6.49; p â€‹< â€‹0.05), anxiety (odds ratio: 3.68-8.84; p â€‹< â€‹0.05), and stress (odds ratio: 2.15-5.21; p â€‹< â€‹0.05). Moreover, the maintenance of practice frequency during the pandemic was associated with higher odds of normal levels of depression (2.27; 1.39-3.79), anxiety (1.97; 1.25-3.10), and stress (1.97; 1.32-2.96). In conclusion, our findings indicated that a higher level of yoga practice was associated with better mental health levels during the COVID-19 pandemic.

5.
J Hum Nutr Diet ; 35(6): 1136-1150, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377488

RESUMO

BACKGROUND: The energy-adjusted Dietary Inflammatory Index (E-DII™) has been associated with a high body mass index and markers of chronic diseases. Also, pro-inflammatory diets with a high E-DII have been positively associated with metabolic disturbances such as glucose intolerance and type II diabetes mellitus. However, it is unclear whether E-DII scores are positively associated with body fat percentage and visceral fat per se. This cross-sectional study aimed to evaluate whether the E-DII is associated with body fat content and metabolic health indicators in lean and obese young men. METHODS: The present study was conducted on 59 participants, without comorbidities, not using tobacco, medication and nutritional supplements. Dietary data were obtained by 3-day food records to calculate E-DII scores based on 28 food parameters. Body composition was assessed by dual X-ray absorptiometry (DXA). Blood samples were taken to measure fasting glucose, insulin, triacylglycerols, total cholesterol, and low- and high-density lipoprotein cholesterol. An oral glucose tolerance test also was performed. Associations were determined by mixed-effects linear regression. RESULTS: E-DII scores ranged from -3.48 to +3.10. Energy intake was similar across E-DII tertiles. After adjusting for covariates, the highest E-DII tertile was associated with increased body fat, visceral adipose tissue and waist circumference. There was no association between E-DII scores and glycaemic parameters. CONCLUSIONS: In young participants, a dietary pattern with a higher E-DII (i.e., pro-inflammatory) score was associated with high body fat and markers of central adiposity assessed by DXA, regardless of body mass.


Assuntos
Diabetes Mellitus Tipo 2 , Gordura Intra-Abdominal , Adulto , Masculino , Humanos , Diabetes Mellitus Tipo 2/complicações , Estudos Transversais , Dieta , Índice de Massa Corporal , Obesidade/complicações , Tecido Adiposo , HDL-Colesterol , Biomarcadores , Inflamação
6.
Nutr Health ; 28(4): 701-709, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35234065

RESUMO

Background: The coronavirus disease (COVID-19) pandemic has promoted changes in lifestyle behaviors, such as food consumption, sleep, and physical activity (PA). Few longitudinal studies have investigated these changes in young adults. Aim: This study aimed to assess lifestyle behaviors before and during the COVID-19 pandemic in young adult males. Methods: 50 young adult males (18-35 years) recruited by posters and social media in Florianopolis, Brazil, provided data on food consumption, PA, and sleep in 2018-2019 (baseline) and during the pandemic in 2020 (follow-up). PA and sleep variables were assessed through self-reported questionnaires. Food records were used to evaluate food consumption. Weight was measured using Bioelectrical impedance analysis at baseline and using self-reported at follow-up. Multilevel linear regression models and generalized linear multilevel were used to test differences between baseline and follow-up. Results: The findings indicated significant changes at follow-up, compared to baseline. Decreased consumption of total fat (ß = -13.32, 95% CI (-22.45; -4.18), p < 0.01), sodium (ß = -1330.72, 95% CI (-1790.63; -870.82), p < 0.01), cholesterol (ß = -212.99, 95% CI (-269.8; -156.18), p < 0.01), total sugars (ß = -65.12, 95% CI (-80.94; -49.29), p < 0.01), alcohol, and sugar-sweetened beverage were observed. Despite that, a slight increase in weight was also observed (80.70 ± 16.37 kg vs. 82.99 ± 15.42 kg, p = 0.000748). Sleep duration increased (ß = 0.7596, 95% CI (0.41; 1.11), p < 0.01), and occupational PA decreased (ß = -1168.1, 95% CI (-1422.33; -913.83), p < 0.01), while domestic (ß = 394.04, 95%CI (114.68; 673.39, p < 0.01)) and leisure PA (ß = 499.91, 95% CI (245.28; 754.53), p < 0.01) increased. Conclusion: Our results suggest that social distancing policies positively impacted eating habits, sleep, and PA patterns. These changes are possibly linked to increased awareness of the need for a healthy lifestyle.


Assuntos
COVID-19 , Pandemias , Adulto Jovem , Masculino , Humanos , Brasil/epidemiologia , COVID-19/epidemiologia , Estudos Longitudinais , SARS-CoV-2 , Comportamento Alimentar , Exercício Físico , Sono , Inquéritos e Questionários
7.
Clin Nutr ESPEN ; 41: 225-233, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33487268

RESUMO

BACKGROUND AND AIM: Relative fat mass (RFM) is a new method to estimate whole-body fat percentage in adults using an anthropometric linear equation. We aimed to assess the association between RFM and body fat (BF), evaluated by dual x-ray absorptiometry (DXA) or bioelectrical impedance (BIA), in young male adults. METHODS: Eighty-one young males were assessed for BF fat and free fat mass (by BIA and DXA), waist circumference. BMI and RFM were then calculated from data collected from the subjects. The agreement between BMI and RFM or BIA/DXA was assessed by Pearson's Correlation and Kappa index. Univariate and multivariate linear regression were applied. RESULTS: Analyzing all the participants together, the correlation between RFM and DXA (rDXA = 0.90) or RFM and BIA (rBIA = 0.88) were slightly higher than the correlation between BMI and DXA (rDXA = 0.79) or BMI and BIA (rBIA: 0.82). When analyzed by BF, low BF (LBF) individuals showed a much higher correlation with RFM (rDXA = 0.58; rBIA = 0.73) than BMI (rDXA = 0.24; rBIA: 0.46). However, subjects with excess BF (EBF) presented similar correlations when comparing RFM (rDXA = 0.80; rBIA = 0.64) and BMI (rDXA = 0.78; rBIA = 0.64). In general, RFM presented a higher strength of agreement with DXA and BIA (kDXA = 0.75; kBIA = 0.67) than BMI (kDXA = 0.63; kBIA = 0.60). Multivariable linear regression also revealed high associations between RFM and DXA or RFM and BIA (r2DXA = 0.85; r2BIA = 0.81). CONCLUSION: Our findings suggest that RFM shows a good correlation and association with BF measured by DXA and BIA in young male adults. Furthermore, RFM seems to be better correlated to BF in LBF individuals when compared to BMI. Therefore, further studies investigating RFM as a tool to assess BF and obesity are motivated.


Assuntos
Adiposidade , Composição Corporal , Absorciometria de Fóton , Adulto , Índice de Massa Corporal , Humanos , Masculino , Obesidade
8.
Nanoscale Adv ; 3(16): 4780-4789, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36134317

RESUMO

We report on the growth of metal- and metal-oxide based nanoparticles (NPs) in heated polyol solutions. For this purpose, NPs are produced by the sputtering of a silver, gold, or a copper target to produce either silver, gold, or copper oxide NPs in pentaerythritol ethoxylate (PEEL) which has been annealed up to 200 °C. The objective of the annealing step is the fine modulation of their size. Thus, the evolution of the NP size and shape after thermal annealing is explained according to collision/coalescence kinetics and the affinity between the metal-/metal-oxide and PEEL molecule. Moreover, highlights of few phenomena arising from the annealing step are described such as (i) the reduction of copper oxide into copper by the polyol process and (ii) the effective formation of carbon dots after annealing at 200 °C.

9.
Rev. bras. ativ. fís. saúde ; 25: 1-7, set. 2020. tab
Artigo em Português | LILACS | ID: biblio-1121581

RESUMO

A pandemia do novo coronavírus (COVID-19) e a crise de saúde pública tem gerado estresse em toda a população. O presente estudo teve como objetivo examinar a prática de Yoga e a sua relação com os níveis de ansiedade, depressão e estresse durante a pandemia de COVID-19. O estudo foi baseado em um questionário on-line anônimo aplicado entre 19 e 26 de maio de 2020, com questões sociodemográficas, sobre a prática de Yoga durante a pandemia e a Escala de Ansiedade Depressão e Estresse (DASS-21). Duzentos e treze participantes completaram o questionário. No geral, foram observados 12,2%, 12,2% e 8,0% de sintomas severos para estresse, ansiedade e depressão, respectivamente. Na análise de regressão logística (expressos em odds ratio; intervalo de confiança de 95%), participantes mais velhos tiveram menores chances de apresentar sintomas severos de estresse (OR = 0,30; IC95%: 0,13 ­ 0,70) e depressão (OR = 0,34; IC95%: 0,12 - 0,92), enquanto o tabagismo aumentou as chances (OR = 7,71; IC95%: 2,36 - 25,21) de sintomas severos de ansiedade. Uma maior experiência na prática de Yoga reduz significativamente as chances de apresentar sintomas severos de estresse (OR = 0,34; IC95% 0,14 - 0,83) e ansiedade (OR = 0,37; IC95% = 0,15 - 0,91). Ademais, houve menores chances de apresentar sintomas severos de estresse em praticantes que realizam um maior número de sessão semanal durante a pandemia (OR = 0,09; IC95% = 0,01 - 0,88), e de sintomas depressivos para aqueles que conseguiram manter a frequência da prática em relação ao período antes da pandemia (OR = 0,23; IC95%: 0,06 - 0,84). Nossos dados observacionais sugerem que praticantes mais experientes e que realizam mais sessões semanal reportam menor impacto psicológico durante a pandemia por COVID-19


The pandemic of the new coronavirus (COVID-19) and the public health crisis has generated stress in the entire population. The present study aimed to examine the practice of Yoga and its relationship with the levels of anxiety, depression, and stress during the COVID-19 pandemic. The study was based on an anonymous online questionnaire applied between 19 and 26 May 2020, with sociodemographic questions, on the prac-tice of Yoga during the pandemic and the Depression and Stress Anxiety Scale (DASS-21). Two hundred and thirteen participants completed the questionnaire. Overall, 12.2%, 12.2%, and 8.0% of severe symptoms for stress, anxiety, and depression were observed, respectively. In the logistic regression analysis (considering odds ratio; 95% confidence interval), older participants were less likely to have severe symptoms of stress (OR = 0.30; 95%CI: 0.13 ­ 0.70) and depression (OR = 0.34; 95%CI: 0.12 - 0.92), while smoking increased the chances (OR = 7.7; 95%CI: 2.36 - 25.21) of severe anxiety symptoms. Greater experience in Yoga practice significantly reduces the chances of experiencing severe symptoms of stress (OR = 0.34; 95%IC 0.14 - 0.83) and anxiety (OR = 0.37; 95%IC: 0.15 - 0.91). Also, there is a reduction in the chances of experiencing severe symptoms of stress in practitioners who perform a greater number of weekly sessions during the pandemic (OR = 0.09; 95%IC: 0.01 - 0.88) and a reduction in depressive symptoms for those who managed to maintain the frequency of the practice in relation to the period before the pandemic (OR = 0.23; 95%IC: 0.06 - 0.84). Our observational data suggest that more experienced practitioners who have more weekly sessions report less psychological impact during the COVID-19 pandemic


Assuntos
Demografia , Saúde Mental , Saúde Pública , Coronavirus , Atividade Motora
10.
Nanotechnology ; 31(45): 455303, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-32726767

RESUMO

Effective methods for the synthesis of high-purity nanoparticles (NPs) have been extensively studied for a few decades. Among others, cold plasma-based sputtering metals onto a liquid substrate appears to be a very promising technique for the synthesis of high-purity NPs. The process enables the production of very small NPs without using any toxic reagents and complex chemical synthesis routes, and enables the synthesis of alloy NPs which can be the first step towards the formation of porous NPs. In this paper, the synthesis of gold-copper alloy NPs has been performed by co-sputtering gold and copper targets over pentaerythritol ethoxylate. The resulting solutions contain a mixture of gold, copper oxide, and alloy NPs having a radius of few angstroms. The annealing of these NPs, inside the solution, has been performed in order to increase their size and further induce the dealloying of the Au-Cu NPs. The resulting NPs exhibit either a nanoporous structure or are self-organized in an agglomerate of small NPs.

11.
Behav Brain Res ; 393: 112770, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32561388

RESUMO

Omega-3-enriched fish oil (FO) and caloric restriction (CR) are nutritional therapeutic approaches that exert an important impact on brain function, behavior, memory, and neuroprotection. Here, we investigate the synergic effects of both therapeutic approaches combined (CR + FO) on behavior (memory, anxiety-like behavior, antidepressant-like behavior), as well as its association with hippocampal brain-derived neurotrophic factor (BDNF) concentrations. Adult male Wistar rats were divided into four dietary groups: Control group (C) - chow ad libitum; CR group - 30 % CR, considering C group food intake; FO group - FO-enriched chow ad libitum; and CR + FO group - FO-enriched 30 % CR chow. After 12 weeks of dietary treatment, behavioural analysis set was conducted, and hippocampal BDNF concentrations were measured. FO group presented anxiolytic-like and antidepressant-like behaviors as well as improved memory in the Morris' water maze. These effects were attenuated by the combined CR + FO treatment. FO group also presented higher BDNF concentrations. There was a positive association between the number of entries in the platform quadrant in the MWM and hippocampal BDNF concentrations (ß = 0.39; R² = 0.15; p = 0.042) and an inverse association between forced swim immobility time and BDNF concentrations (ß = -0.39; R² = 0.15; p = 0.041). Taken together, our data showed that the 12-week FO dietary treatment promoted anxiolytic-like and antidepressant-like behaviors as well as memory improvement, and these effects were associated with BDNF concentrations. Synergic effects of interventions attenuated FO-related behavioral responses and BDNF concentrations and probably reduced hippocampal neuroplasticity.


Assuntos
Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Ansiedade/tratamento farmacológico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Restrição Calórica , Depressão/tratamento farmacológico , Óleos de Peixe/farmacologia , Hipocampo/efeitos dos fármacos , Animais , Ansiolíticos/uso terapêutico , Antidepressivos/uso terapêutico , Óleos de Peixe/uso terapêutico , Hipocampo/metabolismo , Ratos , Ratos Wistar
12.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 73(Pt 4): 767-774, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28762986

RESUMO

The binary phase diagram of Cu-Si is unexpectedly complex in the vicinity of Cu3+xSi. The low-temperature region contains three closely related incommensurately modulated phases denoted, in order of increasing temperature of stability, η''', η'' and η'. The structure analysis of η' has been reported previously [Palatinus et al. (2011). Inorg. Chem. 50, 3743]. Here the structure model for the phases η'' and η''' is reported. The structures could be solved in superspace, but no superspace structure model could be constructed due to the complexity of the modulation functions. Therefore, the structures were described in a supercell approximation, which involved a 4 × 4 × 3 supercell for the η'' phase and a 14 × 14 × 3 supercell for the η''' phase. Both structures are very similar and differ only by a subtle symmetry lowering from η'' to η'''. A comparison of the structure models of η'' and η''' with the reported structure of η' suggests that the reported structure model of η' contains an incorrect assignment of atomic types.

13.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 71(Pt 6): 740-51, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26634732

RESUMO

The recently published method for the structure refinement from three-dimensional precession electron diffraction data using dynamical diffraction theory [Palatinus et al. (2015). Acta Cryst. A71, 235-244] has been applied to a set of experimental data sets from five different samples - Ni2Si, PrVO3, kaolinite, orthopyroxene and mayenite. The data were measured on different instruments and with variable precession angles. For each sample a reliable reference structure was available. A large series of tests revealed that the method provides structure models with an average error in atomic positions typically between 0.01 and 0.02 Å. The obtained structure models are significantly more accurate than models obtained by refinement using kinematical approximation for the calculation of model intensities. The method also allows a reliable determination of site occupancies and determination of absolute structure. Based on the extensive tests, an optimal set of the parameters for the method is proposed.

14.
Acta Crystallogr A Found Adv ; 71(Pt 2): 235-44, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25727873

RESUMO

Accurate structure refinement from electron-diffraction data is not possible without taking the dynamical-diffraction effects into account. A complete three-dimensional model of the structure can be obtained only from a sufficiently complete three-dimensional data set. In this work a method is presented for crystal structure refinement from the data obtained by electron diffraction tomography, possibly combined with precession electron diffraction. The principle of the method is identical to that used in X-ray crystallography: data are collected in a series of small tilt steps around a rotation axis, then intensities are integrated and the structure is optimized by least-squares refinement against the integrated intensities. In the dynamical theory of diffraction, the reflection intensities exhibit a complicated relationship to the orientation and thickness of the crystal as well as to structure factors of other reflections. This complication requires the introduction of several special parameters in the procedure. The method was implemented in the freely available crystallographic computing system Jana2006.

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