17 research outputs found
Mathematical modelling and validation of oil migration on a model chocolate system using magnetic resonance imaging (MRI)
Oil migration is a common problem in chocolate confectionery products leading to quality defects, particularly fat bloom. Magnetic resonance imaging (MRI) is among the most novel techniques as being a non-destructive method to monitor and quantify migration. The main objective of this study was to model oil migration of peanut butter over dark chocolate layer system stored at 30°C with the predictions of a Fickian-based mathematical model. For this purpose, signal intensity (SI) values of chocolate layers containing migrated oil through peanut butter were obtained by using MRI over a time frame of 18 days. Although there are similar studies, different chocolate formulations and peanut butter were used in this study. Experimental data were fitted to a Fickian-based mathematical model. Parameters (C0, b) belonging to time varying boundary conditions and diffusion coefficients (D) were estimated using MATLAB program. Dimensionless equilibrium interface concentrations (C0) were found between 0.70 and 3.53 over time. Time constant (b) was obtained as 0.14 day-1. During storage, D values varied from 8.09×10-11 to 5.42×10-10 m2 s-1. Higher D values were obtained at day 1 indicating faster migration rate
Development of pH Sensitive Alginate/Gum Tragacanth Based Hydrogels for Oral Insulin Delivery
Insulin entrapped alginate-gum tragacanth (ALG-GT) hydrogels at different ALG replacement ratios (100, 75, 50, 25) were prepared through an ionotropic gelation method, followed by chitosan (CH) polyelectrolyte complexation. A mild gelation process without the use of harsh chemicals was proposed to improve insulin efficiency. Retention of almost the full amount of entrapped insulin in a simulated gastric environment and sustained insulin release in simulated intestinal buffer indicated the pH sensitivity of the gels. Insulin release from hydrogels with different formulations showed significant differences (p < 0.05). Time domain (TD) NMR relaxometry experiments also showed the differences for different formulations, and the presence of CH revealed that ALG-GT gel formulation could be used as an oral insulin carrier at optimum concentrations. The hydrogels formulated from biodegradable, biocompatible, and nontoxic natural polymers were seen as promising devices for potential oral insulin delivery
New 3-hydroxyflavone derivatives for probing hydrophobic sites in microheterogeneous systems.
International audienc
A Cross-cultural exploration of problematic Internet use, pathological personality traits, defense mechanisms, coping strategies, and self-esteem in 14 countries
Objectives: The primary objective of this study was to compare the estimates of Problematic Internet Use (PIU) from 14 countries around the world, considering gender. The second objective was to explore the relationships between PIU and personality-related variables (pathological personality traits, defense mechanisms, coping strategies, and self-esteem). Materials and methods: Our total sample consisted of 7726 participants (30.8% male, n = 2378), aged between 18 and 86 years old (M = 25.55; SD = 9.8). Recruited online, they completed several scales about their Internet use, defense mechanisms and coping strategies, self-esteem, and pathological personality traits. Results: The PIU accounted for between 20.5% and 75% of participants using the PIUQ-9, while “self-perception” of PIU with a single item revealed estimates from 2% to 60.1%, with gender differences. Systematically, PIU significantly correlated with two variables: borderline personality traits (from .09 at P < .05 to .42 at P < .01) and immature defense mechanisms (from .13 to .42 at P < .01). Dependent, avoidant, narcissistic, histrionic, and antisocial personality traits were positive predictors of PIU and self-esteem, paranoid and schizoid personalities were negative predictors. Conclusions: This research highlights the many cross-cultural differences. Its design also allows for a better understanding of gender differences
The Prevalence and Predictors of Problematic Mobile Phone Use: a 14-Country Empirical Survey
This study examined (a) differences in estimates of Problematic Mobile Phone Use (PMPU) in adults across 14 countries worldwide and (b) whether personality and psychopathology variables predict PMPU. A sample of 7531 adults (69.6% women; mean age 25.7, SD = 9.9) completed an online survey about PMPU, defense mechanisms, coping strategies, self-esteem, pathological personality traits, and depressive symptoms. The overall mean PMPU score was 104.3 (range 27–270) and 28.1% of the participants self-reported PMPU. Women had significantly higher PMPU overall. Consistent predictors of increased PMPU in the overall sample were younger age, female gender, more hours spent on mobile phone, coping strategies, immature and autistic defenses, depression, and six personality disorders. Significant differences across countries were found in means, self-reported rates, and predictors of PMPU (hours spent, dependent personality, depression, and immature defense were common). Findings pave the way for evidence-based prevention and policy efforts at the public health level