Abstract
A fixed bed adsorption mathematical model has been developed to describe the kinetic separation of hexane isomers when they flow through a packed bed containing the microporous Metal-Organic Framework (MOF) ZIF-8 adsorbent. The flow of inert and adsorbable species through the fixed bed is modeled with fundamental differential equations according to the mass and heat conservation laws, a general isotherm to describe adsorption equilibrium and a lumped kinetic mass transfer mechanism between bulk gas phase and the porous solid. It is shown that a proper combination of two characteristic times (the residence time of the gas in the fixed bed, tfb and the characteristic time of diffusion of solutes into the pores tdif) can lead to very different dynamics of fixed bed adsorbers where in a limiting case can gives rise to a spontaneous breakthrough curves of solutes. The numerical simulations of an experimental breakthrough curve with the developed mathematical model clearly explain the complete separation between linear n-Hexane (nHEX) and the respective branched isomers: 3-Methyl-Pentane (3MP) and 2, 2-Dimethyl-Butane (22DMB). The separation is due to significant differences in the diffusivity parameters tdif between 3MP and 22DMB and the residence time of the gas mixture tfb within the fixed bed. This work shows the importance of mathematical modelling for the comprehension and design of adsorption separation processes. © 2018, Springer International Publishing AG, part of Springer Nature.

Abstract
Experimental incapacity to track microbe-microbe interactions in structures like biofilms, and the complexity inherent to the mathematical modelling of those interactions, raises the need for feasible, alternative modelling approaches. This work proposes an agent-based representation of the diffusion of N-acyl homoserine lactones (AHL) in a multicellular environment formed by Pseudomonas aeruginosa and Candida albicans. Depending on the spatial location, C. albicans cells were variably exposed to AHLs, an observation that might help explain why phenotypic switching of individual cells in biofilms occurred at different time points. The simulation and algebraic results were similar for simpler scenarios, although some statistical differences could be observed (p<0.05). The model was also successfully applied to a more complex scenario representing a small multicellular environment containing C. albicans and P. aeruginosa cells encased in a 3-D matrix. Further development of this model may help create a predictive tool to depict biofilm heterogeneity at the single-cell level.

Abstract
Objectives: The aim of this study was to explore the relationships between eating behavior dimensions and psychopathological symptoms among Portuguese undergraduate students. Methods: We studied 258 participants (62.4% women) regarding eating behavior dimensions (emotional, external and binge eating, flexible and rigid control of eating behavior, and eating self-efficacy), psychopathological distress (as assessed by the Brief Symptom Inventory), and body mass index. In addition to studying bivariate associations between eating behavior dimensions and psychopathological subscales and indexes, what we believe to be a novel analytical approach, considering simultaneously the effects of the overall level of psychopathological distress and the relevance of specific symptoms on the eating behavior dimensions. Results: Emotional, external, and binge eating had positive correlations with psychopathological symptomatology, whereas eating self-efficacy was negatively associated. Conclusions: Multivariate analysis showed that the overall level of psychopathological distress (combined with body mass index, among women) had a larger effect on eating behavior than the relevance of specific symptoms.

Abstract
Introduction: The body skinfolds compressibility is an individual characteristic determined by tissues properties. Compressibility could affect the skinfold thicknesses inducing error in the assessment of subcutaneous adipose tissue and in the estimation of body composition. Objectives: This study aims to firstly describe the time behaviour of eight body skinfolds' physical response to the skinfold calliper pressure during measurement. Methods: Using a digital skinfold calliper that gathers 60 measurements per second, the dynamic response of height skinfolds to pressure was characterized in 36 adult male athletes. To assess the skinfolds compressibility, two points were defined L and H: the S-L corresponds to the lowest value within the 120 measurement the time when it was obtained was defined as T-L. The T-H corresponds to the first moment where the 110% of of the value S-L was measured. The equations of the average of each skinfold as a function of time were obtained from a non-linear fitting. Results: Skinfold compressibility varied according subjects (p< 0.05). Significant differences were found among skinfold sites within S-H, S-L, T-H and T-L, confirming that each skinfold compressibility is different from the other, even within a homogeneous study group. Biceps was the first skinfold to reach the minimum thickness value (T-L= 1.08 +/- 0.38s), while iliac crest was the last one (T-L= 1.63 +/- 0.27s). Given the very good fits that were obtained for all skinfolds (R-2 >= 0.997), it was postulated that the skinfold thickness y changes with time t according to the equation: y = y0 + a/(b + t(n)). Conclusions: Inter and intraindividual skinfolds' variation in compressibility was documented, supporting a reduction in protocolled time during evaluations.

Abstract
In Portugal, tetrahydrobiopterin (BH4)-responsive patients with phenylketonuria (PKU) are identified using a loading test (LT). Phenylalanine/natural protein (Phe/NP) intake is increased to elevate blood Phe prior to the LT. In a longitudinal retrospective study, the impact of Phe/NP titration post-LT in 58 patients (19.6 ± 8.2 years) with PKU during 4 study periods (SPs) was examined. In SP1 (2010-2013), patients were diet treated only; in SP2 (2014), the Phe/NP titration was followed by the LT in SP3 (2015). In SP4 (2016), patients received diet treatment only (n = 49) or BH4 + diet (n = 9). The median percentage blood Phe within the target range was higher in SP1 versus SP4 (64 [28-85] vs 45 [0-66]; P <.001). Our results suggest that transient Phe/NP titration, associated with a deliberate increase in NP, may adversely affect metabolic control. Controlled studies are necessary to examine the longer term impact of temporary increased NP with BH4 LT in non-BH4-responsive patients.

Abstract