24 research outputs found

    The use of stable isotope measurements for monitoring and verification of CO2 storage

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    Stable isotope data can assist in successful monitoring of the fate of injected CO2 in enhanced oil recovery and geological storage projects. This is demonstrated for the International Energy Agency Greenhouse Gas Weyburn-Midale CO2 Monitoring and Storage Project (Saskatchewan) and the Pembina Cardium CO2 Monitoring Project (Alberta) where fluid and gas samples from multiple wells were collected and analyzed for geochemical and isotopic compositions. In both projects, C and O isotope values of injected CO2 were sufficiently distinct from those of background CO2 in the reservoir. Consequently C and O isotope ratios constitute a suitable ‘fingerprint’ for tracing the fate of injected CO2 in the respective reservoirs

    Does outcome measurement of treatment for substance use disorder reflect the personal concerns of patients? A scoping review of measures recommended in Europe

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    There are a growing number of authors stating that outcome measurement in treatment for substance use disorders should go beyond substance use and include other bio-psycho-social variables of interest. However, little is known about which topics tend to be covered by outcome measures and whether they reflect the typical concerns of this patient group. This study followed a scoping review methodology in which 42 outcome measures recommended by an EU agency for substance use disorders were reviewed. We identified the domains of problems covered by these 42 measures and then compared them with 54 domains derived from patients, in a previous study. We also explored how similar the existing measures were in terms of domains covered, and which patient derived domains tended to be represented in those measures. We identified 31domains of problems across the 42 measures, with ‘substance use’ and ‘psychological health’ among the commonest. Most measures were similar in content to each other and multidimensional. Almost all domains of problems identified in the outcome measures corresponded to concerns reported by patients. On the other hand, we found that several topics of relevance for patients were not covered by any of the measure included in our study. This suggests that existing outcome measurement does not always target aspects that affect patients’ lives, as reported directly by patients. Our study shows that outcome measurement needs to adopt a more flexible and comprehensive approach, by taking on board the problems experienced by patients in this population

    Carbon dioxide-water-silicate mineral reactions enhance CO2 storage : evidence from produced fluid measurements and geochemical modeling at the IEA Weyburn-Midale project

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    At the International Energy Agency Greenhouse Gas (IEA GHG) Weyburn-Midale Project in Saskatchewan, Canada, CO2 storage research takes place alongside CO2 enhanced oil recovery (EOR) in the Weyburn oil field. Over four years of production well monitoring at Weyburn, measured changes in chemical and isotopic data for produced aqueous fluids and gases (i.e. an increase in Ca2+, Mg2+, K+, SO42-, HCO3-, and CO2 concentration and a decrease in δ13CHCO3- and δ13CCO2 values), confirm the integrity of CO2 storage, trace CO2 migration and dissolution in the reservoir fluids, and record a range of water-rock- CO2 reactions including carbonate mineral dissolution and alteration of K-feldspar. K-feldspar alteration buffers the pH decrease resulting from CO2 injection, enhances aqueous CO2 storage as HCO3- (ionic trapping) and can lead to mineral storage of CO2 as CaCO3. Geochemical reaction path simulations of the water-mineral- CO2 system reproduce the changes in measured data observed over the first few years, confirming proposed reaction pathways and rates. Extension of these history matched reaction path simulations over 100s of years shows that alteration of K-feldspar and other silicate minerals present in the Weyburn reservoir will lead to further storage of injected CO2 in the aqueous phase and as carbonate minerals

    Brief intervention to reduce risky drinking in pregnancy: study protocol for a randomized controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Risky drinking in pregnancy by UK women is likely to result in many alcohol-exposed pregnancies. Studies from the USA suggest that brief intervention has promise for alcohol risk reduction in antenatal care. However, further research is needed to establish whether this evidence from the USA is applicable to the UK. This pilot study aims to investigate whether pregnant women can be recruited and retained in a randomized controlled trial of brief intervention aimed at reducing risky drinking in women receiving antenatal care.</p> <p>Methods</p> <p>The trial will rehearse the parallel-group, non-blinded design and procedures of a subsequent definitive trial. Over 8 months, women aged 18 years and over (target number 2,742) attending their booking appointment with a community midwife (n = 31) in north-east England will be screened for alcohol consumption using the consumption questions of the Alcohol Use Disorders Identification Test (AUDIT-C). Those screening positive, without a history of substance use or alcohol dependence, with no pregnancy complication, and able to give informed consent, will be invited to participate in the trial (target number 120). Midwives will be randomized in a 1:1 ratio to deliver either treatment as usual (control) or structured brief advice and referral for a 20-minute motivational interviewing session with an alcohol health worker (intervention). As well as demographic and health information, baseline measures will include two 7-day time line follow-back questionnaires and the EuroQoL EQ-5D-3 L questionnaire. Measures will be repeated in telephone follow-ups in the third trimester and at 6 months post-partum, when a questionnaire on use of National Health Service and social care resources will also be completed. Information on pregnancy outcomes and stillbirths will be accessed from central health service records before the follow-ups. Primary outcomes will be rates of eligibility, recruitment, intervention delivery, and retention in the study population, to inform power calculations for a definitive trial. The health-economics component will establish how cost-effectiveness will be assessed, and examine which data on health service resource use should be collected in a main trial. Participants’ views on instruments and procedures will be sought to confirm their acceptability.</p> <p>Discussion</p> <p>The study will produce a full trial protocol with robust sample-size calculations to extend evidence on effectiveness of screening and brief intervention.</p> <p>Trial Registration</p> <p>Current Controlled Trials ISRCTN43218782</p

    Tracing injected CO2 in the Cranfield enhanced oil recovery field (MS, USA) using He, Ne and Ar isotopes

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    The He, Ne and Ar isotopic composition of gases collected in 2009 and 2012 from 13 production wells, injection wells and the CO2 supply pipeline at the Cranfield CO2-enhanced oil recovery field (MS, USA) have been measured in order to determine the extent to which they trace the fate of injected CO2 in the reservoir. In the absence of samples of CO2 pre-injection reservoir gas we use the Ne isotope composition of the production and injection well gases to determine the isotopic composition of the natural gas. The noble gas isotopes display binary mixing trends between the injected CO2 and a CH4-rich natural gas that is characterised by radiogenic He, Ne and Ar isotope ratios. 3He/4He and 40Ar*/4He ratios (where 40Ar* represents the non-atmospheric 40Ar) display coherent relationships with CO2 concentrations that can be used to trace and quantify the injected CO2 in an engineered site over a sustained period of injection. The presence of a small amount of air-derived Ar, from a non-atmospheric source, in many gas samples rules out using 40Ar/36Ar to track the injected CO2. The noble gases identify the loss of a significant proportion of the CO2 from the gas phase sampled by five production wells in 2009. Using 3He/4He and 40Ar*/4He ratios to reconstruct the major gas composition, it appears that between 22% and 96% of the CO2 has been lost in individual wells. This study demonstrates that the naturally occurring noble gases have the potential to trace the fate and quantify the sequestration of CO2 at injection sites

    Review article: pharmacotherapy for alcohol dependence - the why, the what and the wherefore

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    BACKGROUND: The development of alcohol dependence is associated with significant morbidity and mortality. For the majority of affected people the most appropriate goal, in terms of drinking behaviour, is abstinence from alcohol. Psychosocial intervention is the mainstay of the treatment but adjuvant pharmacotherapy is also available and its use recommended. AIM: To provide an updated analysis of current and potential pharmacotherapeutic options for the management of alcohol dependence. In addition, factors predictive of therapeutic outcome, including compliance and pharmacogenetics, and the current barriers to treatment, including doctors' unwillingness to prescribe these agents, will be explored. METHODS: Relevant papers were selected for review following extensive, language- and date-unrestricted, electronic and manual searches of the literature. RESULTS: Acamprosate and naltrexone have a substantial evidence base for overall efficacy, safety and cost-effectiveness while the risks associated with the use of disulfiram are well-known and can be minimised with appropriate patient selection and supervision. Acamprosate can be used safely in patients with liver disease and in those with comorbid mental health issues and co-occurring drug-related problems. A number of other agents are being investigated for potential use for this indication including: baclofen, topiramate and metadoxine. CONCLUSION: Pharmacotherapy for alcohol dependence has been shown to be moderately efficacious with few safety concerns, but it is substantially underutilised. Concerted efforts must be made to remove the barriers to treatment in order to optimise the management of people with this condition
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