Translated Poisson approximation to equilibrium distributions of Markov population processes

The paper is concerned with the equilibrium distributions of continuous-time density dependent Markov processes on the integers. These distributions are known typically to be approximately normal, and the approximation error, as measured in Kolmogorov distance, is of the smallest order that is compatible with their having integer support. Here, an approximation in the much stronger total variation norm is established, without any loss in the asymptotic order of accuracy; the approximating distribution is a translated Poisson distribution having the same variance and (almost) the same mean. Our arguments are based on the Stein-Chen method and Dynkin's formula.Comment: 18 page

A ducted wind turbine simulation model for building simulation

Power production is shifting away from centralized generation plants to production of heat and power at the point of demand. A technology that may play a part in this shift is the ducted wind turbine (DWT). The emergence of small building integrated micro turbines opens up the possibility of utilizing the differential pressures occurring around buildings for local power production. This paper describes work to develop and test a simple mathematical model of a ducted wind turbine and its integration within a building simulation tool. A case study in which the simulation model will be used to analyse of the likely power output from a building incorporating ducted wind turbines within the façade is also presented

Break-up fragments excitation and the freeze-out volume

We investigate, in microcanonical multifragmentation models, the influence of the amount of energy dissipated in break-up fragments excitation on freeze-out volume determination. Assuming a limiting temperature decreasing with nuclear mass, we obtain for the Xe+Sn at 32 MeV/nucleon reaction [J. D. Frankland et al., Nucl. Phys. A689, 905 (2001); A689, 940 (2001)] a freeze-out volume almost half the one deduced using a constant limiting temperature.Comment: 11 pages, 6 figure

Estimation of maximal oxygen consumption and heart rate recovery using the Tecumseh sub-maximal step test and their relationship to cardiovascular risk factors

BACKGROUND: Maximum aerobic capacity (VO2max) is associated with lower cardiovascular and total mortality. Step tests can be used to provide an estimate of (VO2max) in epidemiological or home-based studies. We compared different methods of estimation of VO2max and heart rate recovery and evaluated the relationship of these estimates with cardiovascular risk factors. METHODS: Data were analysed from 2286 participants in the Tecumseh Community Health Study (>16 y and <70 y) who performed a step test. VO2max was estimated from heart rate using three methods and the results compared. The magnitude of heart rate recovery (HRR) and the time constant of recovery based on different time intervals post-exercise were also estimated. RESULTS: Estimated VO2max showed good or poor agreement depending on the method used. VO2max correlated inversely with systolic blood pressure (SBP), body mass index (BMI), total cholesterol, blood glucose following a 100 g oral load (PLG) and Framingham risk score. In a multivariable model age sex, cigarette smoking, SBP, BMI and PLG were significantly inversely associated with VO2max. Correlations with risk factors were strongest for HRR measured over the first 30 s of recovery. Only the time constant calculated from the 3 min post-exercise period correlated significantly with risk factors. CONCLUSIONS: The Tecumseh step test can be used to provide estimates of VO2max and heart rate recovery. Estimated VO2max was inversely associated with higher systolic BP, higher BMI and worse glucose tolerance. Measurements of HRR over the first 30 s and the time constant calculate from the first 3 min of recovery correlate most closely with risk factors

Selected B vitamins and their possible link to the aetiology of age-related sarcopenia: relevance of UK dietary recommendations.

The possible roles of selected B vitamins in the development and progression of sarcopenia are reviewed. Age-related declines in muscle mass and function are associated with huge and increasing costs to healthcare providers. Falls and loss of mobility and independence due to declining muscle mass/function are associated with poor clinical outcomes and their prevention and management are attractive research targets. Nutritional status appears a key modifiable and affordable intervention. There is emerging evidence of sarcopenia being the result not only of diminished anabolic activity but also of declining neurological integrity in older age, which is emerging as an important aspect of the development of age-related decline in muscle mass/function. In this connection, several B vitamins can be viewed as not only cofactors in muscle synthetic processes, but also as neurotrophic agents with involvements in both bioenergetic and trophic pathways. The B vitamins thus selected are examined with respect to their relevance to multiple aspects of neuromuscular function and evidence is considered that requirements, intakes or absorption may be altered in the elderly. In addition, the evidence base for recommended intakes (UK recommended daily allowance) is examined with particular reference to original datasets and their relevance to older individuals. It is possible that inconsistencies in the literature with respect to the nutritional management of sarcopenia may, in part at least, be the result of compromised micronutrient status in some study participants. It is suggested that in order, for example, for intervention with amino acids to be successful, underlying micronutrient deficiencies must first be addressed/eliminated. This article has been accepted for publication and will appear in a revised form, subsequent to peer review and/or editorial input by Cambridge University Press, in Nutrition Research Reviews published by Cambridge University Pres

Kinetic energy spectra for fragments and break-up density in multifragmentation

We investigate the possibility, in nuclear fragmentation, to extract information on nuclear density at break-up from fragment kinetic energy spectra using a simultaneous scenario for fragment emission. The conclusions we derive are different from the recently published results of Viola et al. [Phys. Rev. Lett. 93, (2004), 132701] assuming a sequential fragment emission and claiming that the experimentally observed decrease of peak centroids for kinetic energy spectra of fragments with increasing bombarding energy is due to a monotonic decrease of the break-up density.Comment: 6 pages, 3 figure

Lactobacillus casei strain Shirota selectively modulates macrophage subset cytokine production

Probiotics confer health benefits through many mechanisms including modulation of the gut immune system, dut macrophages regulate immune homeostasis, mounting tolerogenic responses to food and commensal bacteria or immune inflammatory responses to pathogens. Local environment and macrophage subset determine immune response and tolerance, associated with an M2-like phenotype and inflammatory activation with an Ml-like phenotype. Subset predominance will determine immunomodulatory effects of probiotic species such as Lactobacillus casei strain Shirota (LcS). The aim of this study was to investigate differential regulatory effects of LcS on Ml and M2 macrophage subsets. PMA or vitamin D3 differentiated THP-1 human monocytic cells were used to investigate heat-killed LcS and secreted protein tmmunoregulation of Ml and M2 cytokine production, respectively. Additionally, regulation of CD 14lo M2 and CD 14hiMl function was investigated Cytokine expression was measured by ELISA and NFkB activity by reporter assay. Both HK-LcS and SP-LcSaugmented IL-lβ, suppressed IL-6 and differentially regulated TNFα and IL-8, dependent on macrophage subset. HK-LcS and LcS-SP augmented CD14hi Ml TNFa whereas suppressed CD14lo M2 IL-6 and CD14hi Ml NFkB. In conclusion, LcS differentially regulates macrophage cytokines and NFkB activation, is subset-dependent and suggests a cautionary approach to probiotic treatment of mucosal inflammation. Copyright © 2012 by New Century Health Publishers, LLC

High frequency diffraction of an electromagnetic plane wave by an imperfectly conducting rectangular cylinder

Copyright @ 2011 IEEEWe shall consider the the problem of determining the scattered far wave field produced when a plane E-polarized wave is incident on an imperfectly conducting rectangular cylinder. By using the the uniform asymptotic solution for the problem of the diffraction of a plane wave by a right-angled impedance wedge, in conjunction with Keller's method, the a high frequency far field solution to the problem is given

Hyperglycemia Has a Greater Impact on Left Ventricle Function in South Asians Than in Europeans

OBJECTIVE Diabetes is associated with left ventricular (LV) diastolic and systolic dysfunction. South Asians may be at particular risk of developing LV dysfunction owing to a high prevalence of diabetes. We investigated the role of diabetes and hyperglycemia in LV dysfunction in a community-based cohort of older South Asians and white Europeans. RESEARCH DESIGN AND METHODS Conventional and Doppler echocardiography was performed in 999 participants (542 Europeans and 457 South Asians aged 58–86 years) in a population-based study. Anthropometry, fasting bloods, coronary artery calcification scoring, blood pressure, and renal function were measured. RESULTS Diabetes and hyperglycemia across the spectrum of HbA1c had a greater adverse effect on LV function in South Asians than Europeans (N-terminal-probrain natriuretic peptide β ± SE 0.09 ± 0.04, P = 0.01, vs. −0.04 ± 0.05, P = 0.4, P for HbA1c/ethnicity interaction 0.02), diastolic function (E/e′ 0.69 ± 0.12, P < 0.0001, vs. 0.09 ± 0.2, P = 0.6, P for interaction 0.005), and systolic function (s′ −0.11 ± 0.06, P = 0.04, vs. 0.14 ± 0.09, P = 0.1, P for interaction 0.2). Multivariable adjustment for hypertension, microvascular disease, LV mass, coronary disease, and dyslipidemia only partially accounted for the ethnic differences. Adverse LV function in diabetic South Asians could not be accounted for by poorer glycemic control or longer diabetes duration. CONCLUSIONS Diabetes and hyperglycemia have a greater adverse effect on LV function in South Asians than Europeans, incompletely explained by adverse risk factors. South Asians may require earlier and more aggressive treatment of their cardiometabolic risk factors to reduce risks of LV dysfunction