Queueing systems with periodic service

iv+149hlm.;23c

Note on the approximation of distribution on Z+ by mixtures of negative binomial distributions

It is shown that the distributions on Z+ that can be approximated by mixtures of negative binomial distributions, are precisely the so-called Poisson mixtures, i.e., mixtures of Poisson distributions

Fitting discrete distributions on the first two moments

In this paper we present a simple method to fit a discrete distribution on the first two moments of a given distribution. With the fitted distribution we solve approximately Lindley's equation for the discrete-time DIGl1 queue using a moment-iteration method. Numerical results show excellent performance of the method. Key words: two-moment fits, discrete distributions, Lindley's equation, moment-iteration method

Targeting adipose tissue to improve cardiometabolic health

Cardiovascular diseases are the leading cause of death worldwide, with atherosclerosis as most common underlying pathology. Atherosclerosis is characterized by arterial narrowing due to cholesterol and lipid accumulation. Despite available effective cholesterol lowering medication, considerable risk for recurrent vascular events remains. This residual risk is at least in part explained by high blood lipid levels. The research described in this thesis revealed novel therapeutic strategies that improve lipid metabolism and reduce atherosclerosis development in mice. Inhibition of the endocannabinoid system was found to be an effective strategy, as well as concomitant activation of two incretin hormone receptors, namely those for GIP and GLP1. For combined GIP/GLP1 receptor agonism we additionally showed strongly attenuated hepatic steatosis. We were also able to identify additional targets to attenuate hyperlipidemia by studying the mechanisms underlying the strong day-night rhythm of brown adipose tissue, which is a lipid combusting tissue. In this thesis, I also stress the importance of the choice in animal model when studying lipid-modifying interventions, and describe the development of the software tool RandoMice which can be used to improve the quality of preclinical studies by creating well-balanced experimental groups.Financial support by the Netherlands Association for the Study of Obesity (NASO) for the publication of this thesis is gratefully acknowledgedLUMC / Geneeskund

Versterking van het diergezondheidsmanagement in de varkenshouderij: belemmeringen en oplossingsinrichtingen

This report presents barriers and possible solutions to strengthen the animal health management on pig farms

Kinetics of Radioiodinated Heptadecanoic Acid and Metabolites in the Normal and Ischaemic Canine Heart

This study was undertaken to elucidate if the myocardial elimination rate of the radioactivity after administration of radioiodinated heptadecanoic acid was related to beta-oxidation of the fatty acid or related to washout of free radioiodide. In samples of normal and ischaemic myocardium the distribution of the radioactivity over free radioiodide, heptadecanoic acid and lipids was determined. In normal myocardium the major component was free radioiodide, only a small percentage being heptadecanoic acid. In ischaemic myocardium more radiolabelled lipids were present and less free iodide when compared with normal myocardium. The percentage heptadecanoic acid was slightly increased. It is concluded that radioiodinated heptadecanoic acid behaves like the natural analogues regarding uptake and distribution. However, washout of free radioiodide determines the elimination rate as observed during a scintigraphic stud

Phase diagram and dependence of the critical temperature T_c on the pressure for Tl_{0.5}Pb_{0.5}Sr_2Ca_{1-x}Y_xCu_2)_7

Using a mean-field BCS-like approach on the bidimensional extended Hubbard Hamiltonian we calculate the superconducting transition temperature Tc as a function of the hole content nh, for the d-wave and extended-s wave gap symmetries. To describe the pressure effect on Tc we assume it induces a change in the magnitude V of the attractive superconductor potential. This assumption yields an explanation for the intrinsic term, and together with the well known change in nh, we set the critical temperature as Tc=Tc(nh(P),V(P)). With this we obtain a general expansion of Tc in terms of the pressure P and the hole content nh. We apply this expansion to the Tl_{0.5}Pb_{0.5}Sr_2Ca_{1-x}Y_xCu_2)_7 system