Economic shocks and health resilience: lessons from the Russian Federation

Background: Despite extensive research on determinants of health, there is much less information on factors protecting health among those exposed to economic shocks. Using longitudinal data from the Russian Federation in the post-Soviet period, we examined individual-level factors that enhance resilience of health to economic shocks. Methods: Logistic regression analysed factors associated with good self-assessed health (SAH) and health resilience, using pooled samples from the Russia Longitudinal Monitoring Survey-Higher School of Economics (1994–2012). Results: The general population consistently reported ‘average’ SAH, indicating almost invariant trends over the years. Male gender was the strongest predictor of good SAH and health resilience. Other factors positively associated with good SAH were age, higher education, employment, residing in rural areas, living in a larger and/or non-poor household. Among unemployed and those remaining unemployed, residing in rural areas, living in a larger and/or non-poor household remained the strongest predictors of good SAH and health resilience. These same factors were also important for males with recent job loss. Conclusions: Several factors predicting good SAH in the general population also influence health resilience factors among those remaining unemployed and experiencing a job loss. Such factors help to identify those most vulnerable and aid targeting assistance during economic crises

Formation of the "second" bulk in the granular leidenfrost effect

<p>Formation of a "<em>second</em>" bulk in the <strong>granular leidenfrost effect</strong>, for molecular dynamics simulations of 9000 particles of 2mm of diameter, with density 220Kg/m^3, vibrated vertically in a recipient of horizontal area 12 by 12 grain diameter and amplitude 14mm and frequency 38.57 Hz. Colors show the local volumetric density in the vicinity of a particle, and the vertical scale is in layers, where every layer is approximatelly a grain diameter.</p> <p>Left: There is a small translucency on the grains, only to allow a better visibility.</p> <p>Right: Grains with a local density of ~0.35 or lower are made transparent, so bulks can be clearly appreciated.</p

Formation of the bulk in the granular leidenfrost effect

<p>Formation of a bulk in the granular leidenfrost effect, for molecular dynamics simulations of 9000 particles of 2mm of diameter, with density 220Kg/m^3, vibrated vertically in a recipient of horizontal area 12 by 12 grain diameter and amplitude 14mm and frequency 38.57 Hz. Colors show the local volumetric density in the vicinity of a particle, and the vertical scale is in layers, where every layer is approximatelly a grain diameter. We can see that the bulk starts "condensating" in the lower layers of the system, quickly reaching a mean height of ~60 layers.</p> <p>Left: There is a small translucency on the grains, only to allow a better visibility.</p> <p>Right: Grains with a local density of ~0.35 or lower are made transparent, so bulks can be clearly appreciated.</p

bulk formation

<p>Formation of the leiden frost bulk. We use 2mm grains with density 220Kg/m^3n vibrated vertically. We can see that in few cycles there is a conensed zone "hoovering" over a gasified zone. Grains in zones of low density are shown with transparency, for facilitate observing the bulk.</p

Reverse buoyancy in a vibrated granular bed: Computer simulations

We have performed molecular dynamics simulations of an intruder in a vibrated granular bed including interstitial fluid effects to account for the phenomenon of reverse buoyancy. We show that our model is able to reproduce the overall behaviour observed by previous experimental works and is the first finite-elements simulation to show the sinking of intruders lighter than the granular bed. To further advance our comprehension of this phenomenon, we studied the motion of the intruders in a single vibration cycle with respect to the bottom of the granular column, finding a substantial qualitative difference for heavy and light intruders and we compare these results with experiments using fine-sized glass beads. We show that, though heavy intruders seem unaffected by the force due to the fluid, the effect on light intruders is remarkable

Influence of Air on the Bouncing Dynamics of Shallow Vibrated Granular Beds: Kroll’s Model Predictions

In the present work, we explore the modification of the periodicity of the motion of shallow granular columns in the framework of Kroll’s one-dimensional model for the motion of a vibrated bed. Within the model, bed dynamics depend on two parameters, the dimensionless maximum acceleration, Γ, and a dissipative parameter, α, depending on air viscosity, grain density, bed static porosity, oscillation frequency and grain diameter. We show how the bifurcation diagram for the flight time of the bed as a function of Γ changes with α. For α = 0, Kroll’s prediction equals that of the inelastic bouncing ball model. When α is increased, bifurcations shift to higher Γ up to a point where not even a single bifurcation is predicted in a range of Γ where an inelastic bouncing ball displays several bifurcations. We also illustrate how the flight time reduces nonlinearly with increasing α in a monotonic way. We introduce isoperiodic maps to illustrate regions of single, double, or more periodicities in the phase space. We also show and discuss the dependence of the flight time on the parameters entering the definition of α within ranges of those parameters that have been explored in the literature. Grain diameter, grain density and vibration frequency are the most determinant