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The effect of chromium oxide on the properties of simulated nuclear waste glasses
A study of the effect of chromium on the properties of selected glasses was performed in the frame of a Contract between Battelle, Pacific Northwest Laboratories and Nuclear Research Institute, ReZ. In the period from July 1994 to June 1995 two borosilicate glasses of special composition were prepared according to the PNL procedure and their physical and structural characteristics of glasses were studied. This Final Report contains a vast documentation on the properties of all glasses studied. For the preparation of the respective technology more detailed study of physico-chemical properties and crystallinity of investigated systems would be desirable
Dynamic Mode Decomposition for Extrapolating Non-equilibrium Green's Functions Dynamics
The HF-GKBA offers an approximate numerical procedure for propagating the
two-time non-equilibrium Green's function(NEGF). Here we compare the HF-GKBA to
exact results for a variety of systems with long and short-range interactions,
different two-body interaction strengths and various non-equilibrium
preparations. We find excellent agreement between the HF-GKBA and exact time
evolution in models when more realistic long-range exponentially decaying
interactions are considered. This agreement persists for long times and for
intermediate to strong interaction strengths. In large systems, HF-GKBA becomes
prohibitively expensive for long-time evolutions. For this reason, look at the
use of dynamical mode decomposition(DMD) to reconstruct long-time NEGF
trajectories from a sample of the initial trajectory. Using no more than 16\%
of the total time evolution we reconstruct the total trajectory with high
fidelity. Our results show the potential for DMD to be used in conjunction with
HF-GKBA to calculate long time trajectories in large-scale systems
Approximating values of generalized-reachability stochastic games
Simple stochastic games are turn-based 2½-player games with a reachability objective. The basic question asks whether one player can ensure reaching a given target with at least a given probability. A natural extension is games with a conjunction of such conditions as objective. Despite a plethora of recent results on the analysis of systems with multiple objectives, the decidability of this basic problem remains open. In this paper, we present an algorithm approximating the Pareto frontier of the achievable values to a given precision. Moreover, it is an anytime algorithm, meaning it can be stopped at any time returning the current approximation and its error bound
Prevalence and factors associated with hypertension among rural community dwellers in a local government area, South West Nigeria
Background: Many African countries including Nigeria are said to be at
various stages of an epidemiological transition from communicable to
non-communicable diseases (NCD). Objective: This study determined the
current pattern and correlates of hypertension among adults in some
rural communities in South West Nigeria. Methods: It was a descriptive
cross-sectional study of 1012 individuals across 16 rural communities.
The respondents\u2019 blood pressure, weight, height and waist
circumference were measured. Bivariate and multivariate analyses were
done. Results: Among the participants, 461 (45.6%) had hypertension out
of whom 217 (47.1%) and 244 (52.9%) had stage 1 and stage 2
hypertension respectively. The systolic, diastolic and mean arterial
blood pressures increased with age. The significant predictors of
hypertension were; increasing age (p<0.001), higher waist
circumference (p = 0.01) and overweight / obesity (p = 0.03). While
systolic blood pressure (SBP) had the strongest correlation with age,
waist circumference (WC) was the strongest correlate of diastolic blood
pressure (DBP). Conclusion: Despite being a rural population, there was
a high prevalence of hypertension in the study area
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