19 resultados para Mass-consistent model
Resumo:
The objective of this observational, multicenter study was to evaluate the association of body mass index (BMI) with disease severity and prognosis in patients with non-cystic fibrosis bronchiectasis. A total of 339 patients (197 females, 142 males) diagnosed with non-cystic fibrosis bronchiectasis by high-resolution computed tomography were classified into four groups: underweight (BMI<18.5 kg/m2), normal weight (18.5≤BMI<25.0 kg/m2), overweight (25.0≤BMI<30.0 kg/m2), and obese (BMI≥30.0 kg/m2). Clinical variables expressing disease severity were recorded, and acute exacerbations, hospitalizations, and survival rates were estimated during the follow-up period. The mean BMI was 21.90 kg/m2. The underweight group comprised 28.61% of all patients. BMI was negatively correlated with acute exacerbations, C-reactive protein, erythrocyte sedimentation rate, radiographic extent of bronchiectasis, and chronic colonization by P. aeruginosa and positively correlated with pulmonary function indices. BMI was a significant predictor of hospitalization risk independent of relevant covariates. The 1-, 2-, 3-, and 4-year cumulative survival rates were 94%, 86%, 81%, and 73%, respectively. Survival rates decreased with decreasing BMI (χ2=35.16, P<0.001). The arterial carbon dioxide partial pressure, inspiratory capacity, age, BMI, and predicted percentage of forced expiratory volume in 1 s independently predicted survival in the Cox proportional hazard model. In conclusion, an underweight status was highly prevalent among patients with non-cystic fibrosis bronchiectasis. Patients with a lower BMI were prone to developing more acute exacerbations, worse pulmonary function, amplified systemic inflammation, and chronic colonization by P. aeruginosa. BMI was a major determinant of hospitalization and death risks. BMI should be considered in the routine assessment of patients with non-cystic fibrosis bronchiectasis.
Resumo:
(+)-Dehydrofukinone (DHF) is a major component of the essential oil of Nectandra grandiflora (Lauraceae), and exerts a depressant effect on the central nervous system of fish. However, the neuronal mechanism underlying DHF action remains unknown. This study aimed to investigate the action of DHF on GABAA receptors using a silver catfish (Rhamdia quelen) model. Additionally, we investigated the effect of DHF exposure on stress-induced cortisol modulation. Chemical identification was performed using gas chromatography-mass spectrometry and purity was evaluated using gas chromatography with a flame ionization detector. To an aquarium, we applied between 2.5 and 50 mg/L DHF diluted in ethanol, in combination with 42.7 mg/L diazepam. DHF within the range of 10-20 mg/L acted collaboratively in combination with diazepam, but the sedative action of DHF was reversed by 3 mg/L flumazenil. Additionally, fish exposed for 24 h to 2.5-20 mg/L DHF showed no side effects and there was sustained sedation during the first 12 h of drug exposure with 10-20 mg/L DHF. DHF pretreatment did not increase plasma cortisol levels in fish subjected to a stress protocol. Moreover, the stress-induced cortisol peak was absent following pretreatment with 20 mg/L DHF. DHF proved to be a relatively safe sedative or anesthetic, which interacts with GABAergic and cortisol pathways in fish.
Resumo:
A comparative analysis of the theoretical-experimental study, developed by Hsu on the hydration of Amsoy 71 soybean grain, was performed through several soaking experiments using CD 202 soybean at 10, 20, 30, 40, and 50 °C, measuring moisture content over time. The results showed that CD 202 soybean equilibrium moisture content, Xeq, does not depend on temperature and is 21% higher than that found by Hsu, suggesting that soybean cultivar exerts great influence on Xeq. The Hsu model was numerically solved and its parameters were adjusted by the least squares method, with maximum deviations of +/- 10% relative to the experimental values. The limiting step in the mass transfer process during hydration corresponds to water diffusion inside the grain, leading to radial moisture gradients that decrease over time and with an increase in temperature. Regardless of the soybean cultivar, diffusivity increases as temperature or moisture content increases. However, the values of this transport property for Amsoy 71 were superior to those of CD 202, very close at the beginning of hydration at 20 °C and almost three times higher at the end of hydration at 50 °C.
Resumo:
Mass transfer kinetics in osmotic dehydration is usually modeled by Fick's law, empirical models and probabilistic models. The aim of this study was to determine the applicability of Peleg model to investigate the mass transfer during osmotic dehydration of mackerel (Scomber japonicus) slices at different temperatures. Osmotic dehydration was performed on mackerel slices by cooking-infusion in solutions with glycerol and salt (a w = 0.64) at different temperatures: 50, 70, and 90 ºC. Peleg rate constant (K1) (h(g/gdm)-1) varied with temperature variation from 0.761 to 0.396 for water loss, from 5.260 to 2.947 for salt gain, and from 0.854 to 0.566 for glycerol intake. In all cases, it followed the Arrhenius relationship (R²>0.86). The Ea (kJ / mol) values obtained were 16.14; 14.21, and 10.12 for water, salt, and glycerol, respectively. The statistical parameters that qualify the goodness of fit (R²>0.91 and RMSE<0.086) indicate promising applicability of Peleg model.