One size does not fit all - Application of accelerometer thresholds in chronic disease

This is the author accepted manuscript. The final version is available from Oxford University Press via the DOI in this record National Institute for Health Research (NIHR

Sharp Garding inequality on compact Lie groups

In this paper the sharp Garding inequality is established on compact Lie groups. The positivity condition is expressed in the non-commutative phase space in terms of the full symbol, which is defined using the representations of the group. Applications are given to the $L^2$ and Sobolev boundedness of pseudo-differential operators.Comment: 18 page

Demographic Features, Beliefs And Socio–Psychological Impact Of Acne Vulgaris Among Its Sufferers In Two Towns In Nigeria

There is paucity of reports in the demographic knowledge, belief and socio-psychological impact of acne vulgaris sufferers towards the disorder in a black population. This is the first study from Nigeria designed to address this issue. A total of 174 facial acne sufferers completed a self-administered questionnaire, which contained several items mentioning different areas in their belief, knowledge, perception, severity, socio-psychological impact and medication attention. The findings were discussed and compared to those of the Caucasians. The occurrence of the disorder was higher in females (65.0%) compared to the males (35.0%). About 54.0% of the female subjects indicated increase in severity of the disorder during their pre-menstrual period. Also 64.9% of acne sufferers indicated increase in severity during the rainy season, while 93.1% of the population implicated stress to perpetuate the severity of the disorder. Most (75.7%) of the acne sufferers believed that it is caused by oily diet, 40.8% thought that it is hereditary, while barely 5.2% had at sometime sought doctor's attention. Non- prescription products used by acne sufferers were cleansers and cream/lotions. Psychological abnormalities experienced by the sufferers included social inhibition, depression and anxiety. Pain and discomfort are the psychosomatic symptoms. No major differences were found in the beliefs, misconception and socio-psychological impact of acne sufferers in a black population (Nigeria) compared to the Caucasians. There is need to improve the understanding of the disorder in Nigeria through health education programmes

Extension Theory and Krein-type Resolvent Formulas for Nonsmooth Boundary Value Problems

For a strongly elliptic second-order operator $A$ on a bounded domain $\Omega\subset \mathbb{R}^n$ it has been known for many years how to interpret the general closed $L_2(\Omega)$-realizations of $A$ as representing boundary conditions (generally nonlocal), when the domain and coefficients are smooth. The purpose of the present paper is to extend this representation to nonsmooth domains and coefficients, including the case of H\"older $C^{\frac32+\varepsilon}$-smoothness, in such a way that pseudodifferential methods are still available for resolvent constructions and ellipticity considerations. We show how it can be done for domains with $B^\frac32_{p,2}$-smoothness and operators with $H^1_q$-coefficients, for suitable $p>2(n-1)$ and $q>n$. In particular, Kre\u\i{}n-type resolvent formulas are established in such nonsmooth cases. Some unbounded domains are allowed.Comment: 62 page

Discharge β-Blocker Use and Race after Coronary Artery Bypass Grafting

Introduction: The use of discharge β-blockers after cardiac surgery is associated with a long-term mortality benefit. β-Blockers have been suggested to be less effective in black cardiovascular patients compared with whites. To date, racial differences in the long-term survival of coronary artery bypass grafting (CABG) patients who receive β-blockers at discharge have not been examined. Methods: A retrospective cohort study was conducted on patients undergoing CABG between 2002 and 2011. Long-term survival was compared in patients who were and who were not discharged with β-blockers. Hazard ratios (HR) and 95% confidence intervals (CI) were computed using a Cox regression model. P-for-interaction between race and discharge β-blocker use was computed using a likelihood ratio test. Results: A total of 853 (88%) black (n = 970) and 3,038 (88%) white (n = 3,460) patients had a history of β-blocker use at discharge (N = 4,430). Black patients who received β-blockers survived longer than those not receiving β-blockers and the survival advantage was comparable with white patients (black, adjusted HR = 0.33, 95% CI = 0.23–0.46; white, adjusted HR = 0.48, 95% CI = 0.39–0.58; p-for-interaction = 0.74). Among patients discharged on β-blockers, we did not observe a long-term survival advantage for white compared with black patients (HR = 1.2, 95% CI = 0.95–1.5). Conclusion: β-Blocker use at discharge was associated with a survival advantage among black patients after CABG and a similar association was observed in white patients

Simulating Hard Rigid Bodies

Several physical systems in condensed matter have been modeled approximating their constituent particles as hard objects. The hard spheres model has been indeed one of the cornerstones of the computational and theoretical description in condensed matter. The next level of description is to consider particles as rigid objects of generic shape, which would enrich the possible phenomenology enormously. This kind of modeling will prove to be interesting in all those situations in which steric effects play a relevant role. These include biology, soft matter, granular materials and molecular systems. With a view to developing a general recipe for event-driven Molecular Dynamics simulations of hard rigid bodies, two algorithms for calculating the distance between two convex hard rigid bodies and the contact time of two colliding hard rigid bodies solving a non-linear set of equations will be described. Building on these two methods, an event-driven molecular dynamics algorithm for simulating systems of convex hard rigid bodies will be developed and illustrated in details. In order to optimize the collision detection between very elongated hard rigid bodies, a novel nearest-neighbor list method based on an oriented bounding box will be introduced and fully explained. Efficiency and performance of the new algorithm proposed will be extensively tested for uniaxial hard ellipsoids and superquadrics. Finally applications in various scientific fields will be reported and discussed.Comment: 36 pages, 17 figure

Estimation of Dietary Iron Bioavailability from Food Iron Intake and Iron Status

Currently there are no satisfactory methods for estimating dietary iron absorption (bioavailability) at a population level, but this is essential for deriving dietary reference values using the factorial approach. The aim of this work was to develop a novel approach for estimating dietary iron absorption using a population sample from a sub-section of the UK National Diet and Nutrition Survey (NDNS). Data were analyzed in 873 subjects from the 2000–2001 adult cohort of the NDNS, for whom both dietary intake data and hematological measures (hemoglobin and serum ferritin (SF) concentrations) were available. There were 495 men aged 19–64 y (mean age 42.7±12.1 y) and 378 pre-menopausal women (mean age 35.7±8.2 y). Individual dietary iron requirements were estimated using the Institute of Medicine calculations. A full probability approach was then applied to estimate the prevalence of dietary intakes that were insufficient to meet the needs of the men and women separately, based on their estimated daily iron intake and a series of absorption values ranging from 1–40%. The prevalence of SF concentrations below selected cut-off values (indicating that absorption was not high enough to maintain iron stores) was derived from individual SF concentrations. An estimate of dietary iron absorption required to maintain specified SF values was then calculated by matching the observed prevalence of insufficiency with the prevalence predicted for the series of absorption estimates. Mean daily dietary iron intakes were 13.5 mg for men and 9.8 mg for women. Mean calculated dietary absorption was 8% in men (50th percentile for SF 85 µg/L) and 17% in women (50th percentile for SF 38 µg/L). At a ferritin level of 45 µg/L estimated absorption was similar in men (14%) and women (13%). This new method can be used to calculate dietary iron absorption at a population level using data describing total iron intake and SF concentration

Factors Associated with Objectively Assessed Physical Activity Levels of Heart Failure Patients

This is the final version. Available on open access from Longdom Publishing via the DOI in this recordAim: To determine the level of objectively measured moderate-to-vigorous physical activity (MVPA) in patients with heart failure (HF), and to assess the association between MVPA and patient sociodemographic, exercise capacity, and health status factors. Methods: Baseline MVPA data was available in 247 HF patients with 7-day wrist-worn accelerometry from two randomized controlled trials. Associations between MVPA and patient sociodemographic, exercise capacity, and health status factors were assessed using univariate and multivariable linear regression models. Results: 247 patients (28% female, mean age 71 ± 10 years) with HF with reduced ejection fraction (n=198) and preserved ejection fraction (n=49) were included in the analysis. Average MVPA was 283. 3 min/week and ranged widely from a minimum of 0 mins/week to maximum of 2626. 7 mins/week (standard deviation: 404. 1 mins/week). 111 (45%) of patients had a level of PA that met current guidelines of at least 150 minutes/week of MVPA. Multivariable regression showed patient’s age, body mass index, employment status, smoking status, New York Heart Association class, NT-proBNP and exercise capacity to be strongly associated (p<0. 001) with the level of MVPA (p<0. 001). Conclusion: Whilst 45% of HF patients had objectively measured levels of MVPA that met current PA recommendations, we observed a wide range in the level of MVPA across this patient sample. As a number of factors were found to be associated with MVPA our findings provide important information for future interventions aiming to increase MVPA in HF patients.University of ExeterNational Institute for Health Research (NIHR

A Conformally Invariant Holographic Two-Point Function on the Berger Sphere

We apply our previous work on Green's functions for the four-dimensional quaternionic Taub-NUT manifold to obtain a scalar two-point function on the homogeneously squashed three-sphere (otherwise known as the Berger sphere), which lies at its conformal infinity. Using basic notions from conformal geometry and the theory of boundary value problems, in particular the Dirichlet-to-Robin operator, we establish that our two-point correlation function is conformally invariant and corresponds to a boundary operator of conformal dimension one. It is plausible that the methods we use could have more general applications in an AdS/CFT context.Comment: 1+49 pages, no figures. v2: Several typos correcte

Immediate remote ischemic postconditioning after hypoxia ischemia in piglets protects cerebral white matter but not grey matter

Remote ischemic postconditioning (RIPostC) is a promising therapeutic intervention whereby brief episodes of ischemia/reperfusion of one organ (limb) mitigate damage in another organ (brain) that has experienced severe hypoxia-ischemia. Our aim was to assess whether RIPostC is protective following cerebral hypoxia-ischemia in a piglet model of neonatal encephalopathy (NE) using magnetic resonance spectroscopy (MRS) biomarkers and immunohistochemistry. After hypoxia-ischemia (HI), 16 Large White female newborn piglets were randomized to: (i) no intervention (n = 8); (ii) RIPostC - with four, 10-min cycles of bilateral lower limb ischemia/reperfusion immediately after HI (n = 8). RIPostC reduced the hypoxic-ischemic-induced increase in white matter proton MRS lactate/N acetyl aspartate (p = 0.005) and increased whole brain phosphorus-31 MRS ATP (p = 0.039) over the 48 h after HI. Cell death was reduced with RIPostC in the periventricular white matter (p = 0.03), internal capsule (p = 0.002) and corpus callosum (p = 0.021); there was reduced microglial activation in corpus callosum (p = 0.001) and more surviving oligodendrocytes in corpus callosum (p = 0.029) and periventricular white matter (p = 0.001). Changes in gene expression were detected in the white matter at 48 h, including KATP channel and endothelin A receptor. Immediate RIPostC is a potentially safe and promising brain protective therapy for babies with NE with protection in white but not grey matter