Barriers and challenges for primary and secondary prevention of heart disease in sub-Saharan Africa

The diverse people of sub-Saharan Africa face a number of paradoxical challenges arising from economic development and urbanisation, including an increasing prevalence of noncommunicable forms of heart disease. Prevention programmes designed not only to detect those with established and often disabling forms of heart disease, but prevent disease progression and a premature death, are an obvious priority in this setting. This review article reflects on the barriers and challenges to effective primary and secondary prevention of heart disease in sub-Saharan Africa by (a) examining what residual issues challenge effective prevention in high-income countries? (b) what are the key ingredients to an integrated programme of primary and secondary prevention across the lifespan (from the population to individual)? and (c) considering the first two points, what are the barriers and challenges in sub-Saharan Africa to implementing cost-effective primary and secondary prevention using a systematic approach to “who, what and how”

Non-minimal Maxwell-Chern-Simons theory and the composite Fermion model

The magnetic field redefinition in Jain's composite fermion model for the fractional quantum Hall effect is shown to be effectively described by a mean-field approximation of a model containing a Maxwell-Chern-Simons gauge field non-minimally coupled to matter. Also an explicit non-relativistic limit of the non-minimal (2+1)D Dirac equation is derived.Comment: 10 pages, no figure

Are ECG abnormalities common in black Africans with heart failure? Results from the Heart of Soweto study

Background: The “Heart of Soweto” study is currently examining the pattern of cardiovascular disease (CVD) in Soweto, South Africa. Methods: As part of a large clinical registry of CVD patients presenting to the Chris Hani Baragwanath Hospital in Soweto, a 12-lead ECG was performed on 91% of “de novo” cases in 2006. Systematic analysis of the ECGs of heart failure patients was performed using detailed Minnesota coding. Results: A total of 756 de novo patients with HF (57% women, 88% Black African and mean age of 55 ± 16 years) had a 12-lead ECG. Overall, a major ECG abnormality was detected in 91% of cases consisting of ST segment changes, T wave changes, bundle branch blocks and arrhythmias. Minor abnormalities were noted in 97% of ECGs, such as axis deviation and high amplitude R waves. Left ventricular hypertrophy was evident in 15% (22% in those with a dilated cardiomyopathy) and a bundle branch block in 8% of ECGs (11% in those with an ischemic cardiomyopathy). Conclusion: Detailed examination of 12-lead ECGs of a large group of previously undiagnosed patients with HF in the Heart of Soweto study revealed many identifiable abnormalities. In addition to reconfirming the clinical utility of this cheap and practical diagnostic tool, these data highlight its potential role in screening for heart disease, particularly in low income communities

de Haas-van Alphen effect investigations of the electronic structure of pure and aluminum-doped MgB_2

Understanding the superconducting properties of MgB_2 is based strongly on knowledge of its electronic structure. In this paper we review experimental measurements of the Fermi surface parameters of pure and Al-doped MgB_2 using the de Haas-van Alphen (dHvA) effect. In general, the measurements are in excellent agreement with the theoretical predictions of the electronic structure, including the strength of the electron-phonon coupling on each Fermi surface sheet. For the Al doped samples, we are able to measure how the band structure changes with doping and again these are in excellent agreement with calculations based on the virtual crystal approximation. We also review work on the dHvA effect in the superconducting state.Comment: Contribution to the special issue of Physica C "Superconductivity in MgB2: Physics and Applications" (10 Pages with figures

Is there an association between sleeping patterns and other environmental factors with obesity and blood pressure in an urban African population?

Beyond changing dietary patterns, there is a paucity of data to fully explain the high prevalence of obesity and hypertension in urban African populations. The aim of this study was to determine whether other environmental factors (including sleep duration, smoking and physical activity) are related to body anthropometry and blood pressure (BP). Data were collected on 1311 subjects, attending two primary health care clinics in Soweto, South Africa. Questionnaires were used to obtain data on education, employment, exercise, smoking and sleep duration. Anthropometric and BP measurements were taken. Subjects comprised 862 women (mean age 41 ± 16 years and mean BMI 29.9 ± 9.2 kg/m 2 ) and 449 men (38 ± 14 years and 24.8 ± 8.3 kg/m 2 ). In females, ANOVA showed that former smokers had a higher BMI (p 30 minutes was related to a lower BMI (β = -0.04, p30 minutes/day was related to lower systolic (β = -0.02, p<0.05) and lower diastolic BP (β = -0.02, p = 0.05). Longer night time sleep duration was associated with higher diastolic (β = 0.005, p<0.01) and systolic BP (β = 0.003, p<0.05) in females. No health benefits were noted for physical activity. These data suggest that environmental factors rarely collected in African populations are related, in gender-specific ways, to body anthropometry and blood pressure. Further research is required to fully elucidate these associations and how they might be translated into public health programs to combat high levels of obesity and hypertension

New generation of artificial microRNA and synthetic trans-acting small interfering RNA vectors for efficient gene silencing in Arabidopsis

[EN] Artificial microRNAs (amiRNAs) and synthetic trans-acting small interfering RNAs (syn-tasiRNAs) are used for small RNA-based, specific gene silencing or knockdown in plants. Current methods to generate amiRNA or syn-tasiRNA constructs are not well adapted for cost-effective, large-scale production or for multiplexing to specifically suppress multiple targets. Here, we describe simple, fast, and cost-effective methods with high-throughput capability to generate amiRNA and multiplexed syn-tasiRNA constructs for efficient gene silencing in Arabidopsis (Arabidopsis thaliana) and other plant species. amiRNA or syn-tasiRNA inserts resulting from the annealing of two overlapping and partially complementary oligonucleotides are ligated directionally into a zero background BsaI/ccdB-based expression vector. BsaI/ccdB vectors for amiRNA or syn-tasiRNA cloning and expression contain a modified version of Arabidopsis MIR390a or TAS1c precursors, respectively, in which a fragment of the endogenous sequence was substituted by a ccdB cassette flanked by two BsaI sites. Several amiRNA and syn-tasiRNA sequences designed to target one or more endogenous genes were validated in transgenic plants that (1) exhibited the expected phenotypes predicted by loss of target gene function, (2) accumulated high levels of accurately processed amiRNAs or syn-tasiRNAs, and (3) had reduced levels of the corresponding target RNAs.This work was supported by the National Science Foundation (grant nos. MCB-0956526 and MCB-1231726), the National Institutes of Health (grant no. AI043288), the Japan Society for the Promotion of Science (postdoctoral fellowship to A.T.), and the National Institute of Food and Agriculture (postdoctoral fellowship no. MOW-2012-01361 to N.F.)Carbonell, A.; Takeda, A.; Fahlgren, N.; Johnson, SC.; Cuperus, JT.; Carrington, JC. (2014). New generation of artificial microRNA and synthetic trans-acting small interfering RNA vectors for efficient gene silencing in Arabidopsis. PLANT PHYSIOLOGY. 165(1):15-29. https://doi.org/10.1104/pp.113.234989S1529165

Formal Specification and Testing of a Management Architecture

The importance of network and distributed systems management to supply and maintain services required by users has led to a demand for management facilities. Open network management is assisted by representing the system resources to be managed as objects, and providing standard services and protocols for interrogating and manipulating these objects. This paper examines the application of formal description techniques to the specification of managed objects by presenting a case study in the specification and testing of a management architecture. We describe a formal specification of a management architecture suitable for scheduling and distributing services across nodes in a distributed system. In addition, we show how formal specifications can be used to generate conformance tests for the management architecture

Quasiparticle spectrum in the vortex state of d-wave superconductors

Quasiparticle spectrum associated with the nodal structure in d-wave superconductors is of great interest. We study theoretically the quasi-particle spectrum in a planar magnetic field, where the effect of the magnetic field is treated in terms of the Doppler shift. We obtain the angular dependent specific heat in the presence of a planar magnetic field and impurities, both in the superclean limit (Gamma/Delta << H/H_{c2}<< 1) and in the clean limit (H/H_{c2} << Gamma/Delta <<1). Also a similar analysis is used for the thermal conductivity tensor within the a-b plane. In particular, in contrast to the earlier works, we find a fourfold symmetry term in \kappa_{\parallel} and \kappa_{\perp} \sim -H \sin(2\theta) where kappa_{perp} are the diagonal- and the off-diagonal components of the thermal conductivity tensor and \theta is the angle between the heat current and the magnetic field.Comment: RevTex, 5 pages, 5 postscript figure