CO 2 capture and storage (CCS) has the potential to develop into an important tool to address climate change. Given society’s present reliance on fossil fuels, widespread adoption of CCS appears indispensable for meeting stringent climate targets. We argue that for conventional CCS to become a successful climate mitigation technology—which by necessity has to operate on a large scale—it may need to be complemented with air capture, removing CO 2 directly from the atmosphere. Air capture of CO 2 could act as insurance against CO 2 leaking from storage and furthermore may provide an option for dealing with emissions from mobile dispersed sources such as automobiles and airplanes.

The results of this systematic review and meta-analysis indicate that some dietary patterns may be associated with breast cancer risk.

Background: Physical activity (PA) interventions are generally effective in supporting short-term

Large food portions may be facilitating excess energy intake (EI) and adiposity among adults. The present study aimed to assess the extent to which EI and amounts of foods consumed are influenced by the availability of different-sized food portions. A randomised within-subject cross-over, fully residential design was used, where forty-three (twenty-one men and twenty-two women) normal-weight and overweight adults were randomly allocated to two separate 4 d periods where they were presented with either 'standard' or 'large' food portions of the same foods and beverages. The main outcome measures were the amount of food (g) and EI (MJ) consumed throughout each study period. Mean EI over 4 d was significantly higher on the large portion condition compared with the standard condition in the total group (59·1 (SD 6·6) v. 52·2 (SD 14·3) MJ; P¼ 0·020); men and women increased their EI by 17 % (10 (SD 6·5) MJ; P,0·001) and 10 % (4 (SD 6·5) MJ; P¼0·005) respectively when served the large food portions relative to the standard food portions. The increased intakes were sustained over the 4 d in the large portion condition with little evidence of down-regulation of EI and food intake being made by subjects. Increased food portion size resulted in significant and sustained increases in EI in men and women over 4 d under fully residential conditions. The availability and consumption of larger portions of food may be a significant factor contributing to excess EI and adiposity. The burgeoning rates of obesity in genetically stable populations such as in Europe and North America suggest that an increasingly obesogenic environment is the major driving force behind this epidemic (1) . Fostering the delicate balance between energy intake (EI) and energy expenditure to maintain a healthy body weight is now exceedingly difficult for many individuals. In the past few decades several key environmental and cultural factors have converged to increase the probability of over-eating in the face of reduced energy needs.One environmental factor which has become the focus of attention is that of food portion size, which has been increasing steadily over the past two decades in parallel with the rise in overweight and obesity (2,3) . Studies have demonstrated that portions of food sold in supermarkets, fast food establishments and restaurants have steadily increased since the mid 1980s (3,4) , a trend that has been most apparent and best documented in the USA. Consequently, it is hypothesised that increasing portion sizes of food may be undermining normal appetite control and inciting over-eating.One possible reason for over-eating is that consumers tend to eat what they are served (5) , even if it is an inappropriate amount for their energy needs, and consequently may not compensate for this overconsumption at subsequent eating occasions. Indeed, it may be the case that the availability of larger food portions may have a greater impact on food consumption than physiological satiety cues.However, despite pervasive commercial trends towards la...

PAIGE resulted in significantly greater weight loss at 6 months compared with usual care. Such weight loss could prove beneficial in terms of better long-term health and subsequent prevention of type 2 diabetes in overweight women with previous GDM. Future interventions must consider recruitment strategies, timing of the intervention, and inclusion of partners and/or other family members.

There were a number of methodological and statistical limitations in the evidence base. In future, prespecified formal mediation tests should be carried out and could be aided by a formal framework. Social and environmental variables should be considered in addition to intrapersonal variables. Improving knowledge of how to change hypothesized mediators, based on theory and evidence, will reveal how physical activity behavior change maintenance can be achieved. Maintenance research would be enhanced by establishing a formal definition of behavior change "maintenance." PROSPERO registration: PROSPERO 2015:CRD- 42015025462.

In order to meet the challenge of climate change while allowing for continued economic development, the world will have to adopt a net zero carbon energy infrastructure. Due to the world's large stock of low-cost fossil fuels, there is strong motivation to explore the opportunities for capturing the CO 2 that is produced in the combustion of fossil fuels and keeping it out of the atmosphere. Three distinct sets of technologies are needed to allow for climate neutral use of fossil fuels: (1) capture of CO 2 at concentrated sources like electric power plants, future hydrogen production plants and steel and cement plants;(2) capture of CO 2 from the air; and (3) the safe and permanent storage of CO 2 away from the atmosphere. A strong regime of carbon accounting is also necessary to gain the public's trust in the safety and permanence of CO 2 storage. This paper begins with an extensive overview of carbon capture and storage technologies, and then presents a vision for the potential implementation of carbon capture and storage, drawing upon new ideas such as air capture technology, leakage insurance, and monitoring using a radioactive isotope such as C-14. These innovations, which may provide a partial solution for managing the risks associated with long-term carbon storage, are not well developed in the existing literature and deserve greater study.

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