Insomnia symptoms as a cause of type 2 diabetes Incidence: a 20 year cohort study

Background Insomnia symptoms are associated with type 2 diabetes incidence but are also associated with a range of potential time-varying covariates which may confound and/or mediate associations. We aimed to assess whether cumulative exposure to insomnia symptoms has a causal effect on type 2 diabetes incidence. Methods A prospective cohort study in the West of Scotland, following respondents for 20 years from age 36. 996 respondents were free of diabetes at baseline and had valid data from up to four follow-up visits. Type 2 diabetes was assessed at the final visit by self-report, taking diabetic medication, or blood-test (HbA1c ≥ 6.5% or 48 mmol/mol). Effects of cumulative insomnia exposure on type 2 diabetes incidence were estimated with traditional regression and marginal structural models, adjusting for time-dependent confounding (smoking, diet, physical inactivity, obesity, heavy drinking, psychiatric distress) as well as for gender and baseline occupational class. Results Traditional regression yielded an odds ratio (OR) of 1.34 (95% CI: 1.06-1.70) for type 2 diabetes incidence for each additional survey wave in which insomnia was reported. Marginal structural models adjusted for prior covariates (assuming concurrently measured covariates were potential mediators), reduced this OR to 1.20 (95% CI: 0.98-1.46), and when concurrent covariates were also included (viewing them as potential confounders) this dropped further to 1.08 (95% CI: 0.85-1.37). Conclusions The association between cumulative experience of insomnia and type 2 diabetes incidence appeared confounded. Evidence for a residual causal effect depended on assumptions as to whether concurrently measured covariates were confounders or mediator

Improved quantification of CO2 storage containment risks - an overview of the SHARP Storage project

Carbon Capture and Storage (CCS) is now maturing in Europe and worldwide with several Net Zero projects emerging. Hence, the need for safe and reliable CO2 storage sites is accelerating and the accurate assessment of large-scale storage options at the gigatonne-per-year is critical. The SHARP project addresses the main priority areas required to improve current technologies to deliver CO2 storage volumes at the scale needed to meet demands for large scale storage. Research needs identified in the industry has provided the base for this well-integrated project with the ambitions to reduce the uncertainty in the geomechanical response to CO2 injection. Six case studies from sites in the North Sea and India will be matured during the projects. Ongoing work includes review of existing stress data, updating and integration of seismic catalogues and planning of new experimental data for improved constitutive models and rock failure attributes. Improved data analysis, compiling data from different sources, and new data generated in the project is expected to provide a base for updated failure risk assessment and more targeted monitoring. An initial assessment of rock failure risk in in progress and will be updated with a "Round 2" failure assessment incorporating new learnings and more mature data. The improved failure risk assessment includes the use of Bayesian statistical approach for quantification of uncertainties in geomechanical properties. Methods to quantify geological containment risk will be developed by reading across event tree techniques from other industries (e.g. nuclear). A set of generic release diagrams have been derived in a series of interdisciplinary workshops as a starting point for risk modellingImproved quantification of CO2 storage containment risks - an overview of the SHARP Storage projectpublishedVersio

Controls on the dissolution of CO 2 plumes in structural traps in deep saline aquifers

Sequestration of carbon dioxide in deep saline aquifers has been proposed and investigated as a viable solution to help mitigate carbon emissions from fossil fuels. Much research has been directed at understanding the transitions of supercritical CO2 from being a mobile fluid phase to being trapped by capillarity or dissolved in groundwater; such transitions lead to a reduction in mobility of CO2 and hence in the risk of leakage to the surface. Following injection, buoyant plumes of CO2 migrate updip towards structural traps in the geological strata; however, some of this CO2 may be capillary trapped in pore spaces or dissolved in groundwater en route. Since CO2 saturated groundwater only has a small CO2 concentration, the dissolution of any large, structurally trapped plumes of CO2 may be controlled by the availability of unsaturated groundwater. In an aquifer of finite vertical extent, this may be rate limited by a combination of (i) the background hydrological flow coupled with (ii) the slow lateral exchange of relatively dense, CO2 saturated groundwater with unsaturated groundwater. In an inclined aquifer, this may be controlled by the slow along-aquifer component of gravity. Structurally trapped plumes of CO2 may therefore persist for many thousands of years, and, since they are potentially highly mobile, may represent an important contribution to the long term risks associated with CO2 sequestration at particular sites

Additional file 2: Appendix 2. of Insomnia symptoms as a cause of type 2 diabetes Incidence: a 20Â year cohort study

Covariate balance. Includes 5 supplementary figures showing how wave-specific weights achieve covariate balance on prior measures of covariates. (DOCX 164 kb

Additional file 1: Appendix 1. of Insomnia symptoms as a cause of type 2 diabetes Incidence: a 20Â year cohort study

Calculation of weights. Gives further technical details of the specific models used to calculate analysis weights. (DOCX 17 kb

Preparing the ground for the implementation of a large-scale CCS demonstration in China based on an IGCC-CCS thermal power plant: The China-EU COACH Project

AbstractThe COACH project (Cooperation Action Within CCS China-EU11EC/FP6 Contract #038966, co-ordinated by F. Kalaydjian, IFP Energies nouvelles, France.) was launched on November 1st 2006 for a period of 3 years, as part of the 6th framework programme of the European Commission22The French Agency for Development (AFD) is gratefully acknowledged for its financial support to the dissemination, knowledge sharing and capacity building activities developed in COACH.. Gathering 20 partners comprising 8 Chinese partners and 12 European partners, the COACH project was conceived as contributing to the first phase of the Near Zero Emission Coal fired power plants (NZEC) programme, a 3-phase programme developed between the European Union and China, aiming at combating climate change by enabling the deployment in China of thermal power plants equipped with CO2 capture and storage (CCS) facilities.The objective of the COACH project was to establish the basis for the large-scale use of coal for polygeneration in China with pre-combustion capture, transport and geological storage of CO2. Main efforts were place on a future CCS demonstration operated on an Integrated Gasification Combined Cycle (IGCC) thermal power plant fully equipped for converting and splitting the produced syngas into a hydrogen-rich fuel gas and CO2, and with a subsequent storage of CO2 in either mature hydrocarbon reservoirs (Dagang or Shengli oil provinces), deep saline formations or unmineable coal seams. Focus was made on the emission sources and storage sites located in the part of the Bohai Basin in the Shandong Province.The paper will present the main outcomes of the project as follows : •Structuring the China-EU COACH venture: In order to enabling the sharing of knowledge between European and Chinese COACH partners and building capacity a survey of CCS activities was performed, workshops were organised in EU and China, a cooperative website was created and two one-week long CCS schools were organised in China gathering more than 100 students 2/3 thereof coming from China and the remaining from Europe;•Technical actions and challenges relating to CCS, gasification and polygeneration: A generic IGCC concept implemented with CO2 capture was defined and compared against a plain IGCC based on the GreenGen Phase I system without CO2 capture. A detailed analysis of technologies needed for implementing an option for CO2 capture in an IGCC process with provision for production of electricity and methanol was carried out as well as a cost analysis of both CO2 capture and transport;•Geological assessment and storage sites mapping: A quantitative assessment of the potential storage sites (the Dagang and Shengli oil provinces, the deep saline aquifers nearby and the Kailuan coal mining area) was performed along with a mapping of the possible transport infrastructure (by pipelines or ships) that could be developed to connect CO2 sources to CO2 sites; with regards to storage capacity, the main capacity was found to reside in the deep saline aquifers (several giga tonnes) but would require further geological investigation for delivering definite values. The storage potential in oil fields was found to be much smaller (less than one giga tonne) but could provide opportunities for enhanced oil recovery. Finally, the coals of Kailuan mining area exhibit a high ability to adsorb CO2 and provide enhanced coalbed methane recovery, but their injectivity remains to be verified.•Case studies and recommendations for CCS demonstration in China: By integrating results obtained in the previous tasks dealing with CO2 capture and CO2 storage, two scenarios (one small scale–from 0.1 to 1 million tonnes of CO2 per year, one large scale–2 to 3 million tonnes of CO2 per year) were designed to screen options for a possible CCS demonstration project. These alternative CO2 streams are both considered captured from the GreenGen IGCC power plant in Tianjin and transported to one or more geological formations in the Bohai Bay geological basin for permanent disposal. Storage for the smaller scale scenario could be accommodated in the Dagang or Shengli oilfields. Storage for the larger scale scenario (2–3 million tonnes a year) could be accommodated in the Shengli oilfield province (in a number of fields) or potentially in the saline formations that can be found in the Huimin sub-basin area. For each of these options, a preliminary risk assessment was performed. A thorough cost analysis was performed. Policy and regulation issues pertaining to a shift towards CCS in China. The 3-year targeted cooperative actions under the COACH project have mobilised capacities in China and Europe and paved the ground for subsequent CCS demonstrations in China. The next phase of the China-EU NZEC programme should start in 2010 and deliver FEED studies which should allow starting operating a CCS demonstration in China by 2015

Improved quantification of CO2 storage containment risks - an overview of the SHARP Storage project

Carbon Capture and Storage (CCS) is now maturing in Europe and worldwide with several Net Zero projects emerging. Hence, the need for safe and reliable CO2 storage sites is accelerating and the accurate assessment of large-scale storage options at the gigatonne-per-year is critical. The SHARP project addresses the main priority areas required to improve current technologies to deliver CO2 storage volumes at the scale needed to meet demands for large scale storage. Research needs identified in the industry has provided the base for this well-integrated project with the ambitions to reduce the uncertainty in the geomechanical response to CO2 injection. Six case studies from sites in the North Sea and India will be matured during the projects. Ongoing work includes review of existing stress data, updating and integration of seismic catalogues and planning of new experimental data for improved constitutive models and rock failure attributes. Improved data analysis, compiling data from different sources, and new data generated in the project is expected to provide a base for updated failure risk assessment and more targeted monitoring. An initial assessment of rock failure risk in in progress and will be updated with a "Round 2" failure assessment incorporating new learnings and more mature data. The improved failure risk assessment includes the use of Bayesian statistical approach for quantification of uncertainties in geomechanical properties. Methods to quantify geological containment risk will be developed by reading across event tree techniques from other industries (e.g. nuclear). A set of generic release diagrams have been derived in a series of interdisciplinary workshops as a starting point for risk modelling