Training after myocardial infarction : Lack of long-term effects on physical capacity and psychological variables

This study evaluated long-term effects of 12 weeks of supervised training, of at least 45 minutes duration with two sessions per week, on physical performance and psychological well-being after myocardial infarction (MI). Sixty-nine patients were randomized to either an exercise or a nonexercise group. Maximum exercise capacity 6 weeks post-MI was inversely related to the acute peak aspartate aminotransferase values in serum, as an index of infarct size. One year post-MI, the increase in level of fitness (10%) in the training group did not significantly exceed (p = .10) that of the controls (2%). No intergroup differences were registered in self-rated psychological well-being and physical scores or in the return to work rate. In the training group, but not in the controls, the change in perceived dyspnoea at leisure- time activities was positively related to the objectively measured peak exercise capacity. We conclude that after MI only marginal improvements in physical performance are achieved 6 months after training is finished, with no long-term psychological benefits apparent versus a usual care program. The adaptive implications of supervised conventional exercise programs post-MI are therefore questioned

Importance of baseline cotinine plasma values in smoking cessation: Results from a double-blind study with nicotine patch

Nicotine replacement by transdermal patches is more effective than placebo in smoking cessation, but has a low success rate after one year (9-18 %). We tested whether this was attributed to insufficient nicotine replacement. We conducted a randomized trial to investigate the effect on outcome of different doses of transdermal nicotine replacement after stratification according to baseline plasma cotinine values. Two hundred and ninety seven adult smokers were enrolled. Those with baseline cotinine ≤250 ng · ml-1 (low cotinine) were randomly assigned to placebo (LC-P) or to 15 mg 16 h nicotine patches (LC-15), and those with baseline cotinine >250 ng · mL-1 (high cotinine) were randomly assigned to 15 mg (HC-15) or 25 mg (HC-25) 16 h nicotine patches. Plasma nicotine and cotinine values, expired carbon monoxide and withdrawal symptoms were measured at scheduled intervals during treatment. Smokers in the LC-15 group had a significantly higher success rate than placebo (28 vs 9 %). Smokers with high baseline cotinine had lower success rates, and a high dose of nicotine did not increase success rate (HC- 25 9 % vs HC-15 11 %). Subjects in the HC-15 group had the lowest percentage of nicotine replacement and a higher prevalence of withdrawal symptoms than the HC-25 group. Replacement was similar in groups LC-15 and HC-25, but the success rate was significantly lower in HC-25 group, despite similar levels of withdrawal symptoms. We conclude that a higher success rate was obtained after one year in smokers with low baseline plasma cotinine values. Determination of plasma cotinine values may be, thus, helpful in identifying smokers who could benefit from transdermal nicotine replacement

Of monopolies and mini grids: case studies from Kenya, Tanzania, Nigeria and Senegal

Recent advances in decentralised renewable electricity systems have undermined long-held assumptions that electricity access and rural electrification can only be achieved via the extension of the national grid. Renewable energy and solar hybrid mini grids are being promoted as one low-cost option to meet Sustainable Energy for All’s commitment to universal energy access by 2030, because of their potential to connect low-income, rural and/or dispersed communities for whom the cost of extending the main grid is considered too expensive. As this paper discusses in relation to four countries in sub-Saharan Africa: Kenya, Tanzania, Nigeria and Senegal, in recent years new private sector actors in renewable energy mini grids have started to emerge, marking a shift away from large-scale diesel or hydro mini grids run by government utilities, and small-scale mini grid development previously led by bi-lateral donors and community organisations on a project-by-project basis. However, there have been considerable governance and regulatory challenges to the development and deployment of renewable energy mini grids at scale, which has often taken place in the absence of national regulation rather than because of it. Moreover, some state-owned electricity utilities and associated institutions have been resistant at once to new private sector actors and decentralised systems. Meanwhile, the term ‘mini grid’ lacks a common definition and is simultaneously associated with energy access as well as productive use, despite the often competing objectives of these end uses. This paper unpacks some of these dynamics through an extensive desk-based study of grey and academic literature and a regulatory comparison of the four case study countries. Building on scholarship from development and energy geography, we argue that a more granular analysis is needed in order to account for the complex and evolving processes of electricity decentralisation in low- and middle-income countries