The sustainability of changes in agricultural technology:The carbon, economic and labour implications of mechanisation and synthetic fertiliser use

New agricultural technologies bring multiple impacts which are hard to predict. Two changes taking place in Indian agriculture are a transition from bullocks to tractors and an associated replacement of manure with synthetic fertilisers. This paper uses primary data to model social, environmental and economic impacts of these transitions in South India. It compares ploughing by bullocks or tractors and the provision of nitrogen from manure or synthetic urea for irrigated rice from the greenhouse gas (GHG), economic and labour perspective. Tractors plough nine times faster than bullocks, use substantially less labour, with no significant difference in GHG emissions. Tractors are twice as costly as bullocks yet remain more popular to hire. The GHG emissions from manure-N paddy are 30 % higher than for urea-N, largely due to the organic matter in manure driving methane emissions. Labour use is significantly higher for manure, and the gender balance is more equal. Manure is substantially more expensive as a source of nutrients compared to synthetic nutrients, yet remains popular when available. This paper demonstrates the need to take a broad approach to analysing the sustainability impacts of new technologies, as trade-offs between different metrics are common

Metabolic effects of smoking cessation

Smoking continues to be the leading cause of preventable death in the USA, despite the vast and widely publicized knowledge about the negative health effects of tobacco smoking. Data show that smoking cessation is often accompanied by weight gain and an improvement in insulin sensitivity over time. However, paradoxically, post-cessation-related obesity might contribute to insulin resistance. Furthermore, post-cessation weight gain is reportedly the number one reason why smokers, especially women, fail to initiate smoking cessation or relapse after initiating smoking cessation. In this Review, we discuss the metabolic effects of stopping smoking and highlight future considerations for smoking cessation programs and therapies to be designed with an emphasis on reducing post-cessation weight gain