Relationship between physical activity and functional capacity change in aged cohort in São Paulo, Brazil

ABSTRACT Objectives: to evaluate the relationship between leisure-time physical activity and functional capacity change among aged people. Methods: we analyzed data of an aged cohort looking for determinants of functional capacity at follow-up. Baseline data were collected between 2007 and 2008 - average follow-up of 3,5 years. A full multivariate linear regression model was built to evaluate functional capacity at the end of the follow-up, controlling for functional capacity at baseline, sociodemographic, health and behavioral characteristics and amount of leisure-time physical activity in the period. Results: final model showed functional capacity independently correlated with age (p<0.001), body mass (p=0.013) and the number of activities of daily living compromised at baseline (p<0.001). Functional capacity improved with increased physical activity but loss statistical significance after adjustments (p=0.384). Conclusions: functional capacity decreases with increased age, increased loss of functional capacity at baseline and increased body mass. Albeit a non-significant association, leisure-time physical activity appears as an important modifiable factor.

Estimating the impact of neonatal abstinence system interventions on Medicaid: an incremental cost analysis

Background Neonatal abstinence syndrome (NAS) incidence has significantly increased in the US in recent years. It is therefore important to develop effective intervention protocols that mitigate the long-term consequences of this condition for the mother, her child, and the community. Methods We used Monte Carlo simulation to estimate the impact of four interventions for NAS and their combinations on pregnant women with opioid use disorder. The key outputs were changes in incremental costs from baseline from the Medicaid perspective and from a total systems perspective and effect size changes. Simulation parameters and costs were based on the literature and baseline model validation was performed using Medicaid claims for Indiana. Results Compared to baseline, the resulting simulation estimates showed that three interventions significantly decreased Medicaid incremental costs by 8% (mandatory opioid testing (MOT)), 4% (patient navigators), and 3% (peer recovery coaches). The combination of the three interventions reduced Medicaid direct costs by 26%. Reductions were similar for total system incremental costs (ranging from 2 to 24%), though MOT was found to increase costs of overdose death based on productivity loss. NAS case reductions ranged from 1% (capacity change) to 13% (MOT). Conclusions Using systems-based modeling, we showed that costs associated with NAS can be significantly reduced. However, effective implementation would require the involvement and coordination of several stakeholders. In addition, careful protocols for MOT should be considered to ensure pregnant women don’t forgo prenatal care for fear of punitive consequences.

Thermodynamics and Intermolecular Interactions of Nicotinamide in Neat and Binary Solutions: Experimental Measurements and COSMO-RS Concentration Dependent Reactions Investigations

In this study, the temperature-dependent solubility of nicotinamide (niacin) was measured in six neat solvents and five aqueous-organic binary mixtures (methanol, 1,4-dioxane, acetonitrile, DMSO and DMF). It was discovered that the selected set of organic solvents offer all sorts of solvent effects, including co-solvent, synergistic, and anti-solvent features, enabling flexible tuning of niacin solubility. In addition, differential scanning calorimetry was used to characterize the fusion thermodynamics of nicotinamide. In particular, the heat capacity change upon melting was measured. The experimental data were interpreted by means of COSMO-RS-DARE (conductor-like screening model for realistic solvation–dimerization, aggregation, and reaction extension) for concentration dependent reactions. The solute–solute and solute–solvent intermolecular interactions were found to be significant in all of the studied systems, which was proven by the computed mutual affinity of the components at the saturated conditions. The values of the Gibbs free energies of pair formation were derived at an advanced level of theory (MP2), including corrections for electron correlation and zero point vibrational energy (ZPE). In all of the studied systems the self-association of nicotinamide was found to be a predominant intermolecular complex, irrespective of the temperature and composition of the binary system. The application of the COSMO-RS-DARE approach led to a perfect match between the computed and measured solubility data, by optimizing the parameter of intermolecular interactions.

Flight Status— ‘Grounded Indefinitely’: An Analysis of the Impact of COVID-19 on Commercial Aviation

Since the unexpected eruption of COVID-19, travel has been heavily circumscribed by governments in an endeavour to curb the spread of the virus. This research study aimed at conducting a case-study analysis of the impact of the Coronavirus on the commercial aviation industry. It analysed changes in international passenger capacity from originally planned in a sampling of countries from different regions, from January to April 2020, to measure the impact of the pandemic on commercial aviation. The data for capacity change were regressed against days of lockdown and days of global travel ban to determine the extent of their impact. Qualitative data was also analysed to provide a multi-faceted picture. The study found that COVID-19 had a huge influence on commercial aviation during the period observed. Moreover, the restrictions implemented by governments were found to exert a statistically significant impact on the industry, accounting for 84% of the impact on the change in international passenger capacity. The equation generated provides a predictive tool for determining changes in passenger capacity in the foreseeable future if similar restrictive policies are imposed. A qualitative analysis of the context also reveals that airfares will fall in the short run as airlines compete to regain customers, but rise in the long run. The paper thus highlights the importance of government bailouts and the relaxation of specific rules to support airlines during these challenging times. Other necessary measures identified include fleet re-purposing, as well as the institution of additional safety measures to encourage air travel.

pH-Independent Heat Capacity Changes during Phosphorolysis Catalyzed by the Pyrimidine Nucleoside Phosphorylase from Geobacillus thermoglucosidasius

Enzyme-catalyzed reactions sometimes display curvature in their Eyring plots in the absence of denaturation, indicative of a change in activation heat capacity. However, pH and (de)protonation effects on this phenomenon have remained unexplored. Herein, we report a kinetic characterization of the thermophilic pyrimidine nucleoside phosphorylase from <i>Geobacillus thermoglucosidasius</i> across a two-dimensional working space covering 35 °C and 3 pH units with two substrates displaying different pK_a values. Our analysis revealed the presence of a measurable activation heat capacity change in this reaction system, which showed no significant dependence on medium pH or substrate charge. Our results further describe the remarkable effects of a single halide substitution which has a minor influence on the heat capacity change but conveys a significant kinetic effect by lowering the activation enthalpy, causing a >10-fold rate increase. Collectively, our results present an important piece in the understanding of enzymatic systems across multidimensional working spaces where the choice of reaction condition can affect rate, affinity and thermodynamic phenomena independently of one another.<br>

pH-Independent Heat Capacity Changes during Phosphorolysis Catalyzed by the Pyrimidine Nucleoside Phosphorylase from Geobacillus thermoglucosidasius

Enzyme-catalyzed reactions sometimes display curvature in their Eyring plots in the absence of denaturation, indicative of a change in activation heat capacity. However, pH and (de)protonation effects on this phenomenon have remained unexplored. Herein, we report a kinetic characterization of the thermophilic pyrimidine nucleoside phosphorylase from <i>Geobacillus thermoglucosidasius</i> across a two-dimensional working space covering 35 °C and 3 pH units with two substrates displaying different pK_a values. Our analysis revealed the presence of a measurable activation heat capacity change in this reaction system, which showed no significant dependence on medium pH or substrate charge. Our results further describe the remarkable effects of a single halide substitution which has a minor influence on the heat capacity change but conveys a significant kinetic effect by lowering the activation enthalpy, causing a >10-fold rate increase. Collectively, our results present an important piece in the understanding of enzymatic systems across multidimensional working spaces where the choice of reaction condition can affect rate, affinity and thermodynamic phenomena independently of one another.<br>

Immune synapse instructs epigenomic and transcriptomic functional reprogramming in dendritic cells

Understanding the fate of dendritic cells (DCs) after productive immune synapses (postsynaptic DCs) with T cells during antigen presentation has been largely neglected in favor of deciphering the nuances of T cell activation and memory generation. Here, we describe that postsynaptic DCs switch their transcriptomic signature, correlating with epigenomic changes including DNA accessibility and histone methylation. We focus on the chemokine receptor Ccr7 as a proof-of-concept gene that is increased in postsynaptic DCs. Consistent with our epigenomic observations, postsynaptic DCs migrate more efficiently toward CCL19 in vitro and display enhanced homing to draining lymph nodes in vivo. This work describes a previously unknown DC population whose transcriptomics, epigenomics, and migratory capacity change in response to their cognate contact with T cells.

Термодинамический цикл Брайтона с обратимой химической реакцией

The Brighton cycle is considered, where a chemically reacting gas is used as a working substance and its molar weight and heat capacity change because of a reversible chemical reaction. The lower T_low characterizes a cycle with a constant heat supply and upper T_top temperature limits of existence, between these limits the thermal efficiency can vary from 0 to 1. Such unusual properties are manifested due to two factors: the reversibility of the chemical reaction and the special role of chemical work in the transformation heat into mechanical work.