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Low‐frequency forced‐oscillation methods applied to a reservoir sandstone allowed determination of the Young's modulus and Poisson's ratio (from axial loading), bulk modulus (by oscillation of the confining pressure) and shear modulus (from torsional‐forced oscillations) for comparison with conventional ultrasonic data. All tests were performed on a common sandstone core sample from an oil reservoir offshore West Africa. The results show a steady increase in ultrasonic velocities and shear modulus of the dry specimen as functions of pressure, which suggests a progressive closure of the inter‐granular contacts. An increase of bulk and Young's moduli and Poisson's ratio is observed on decane saturation of the sample when tested with a sufficiently small dead volume. This observation, consistent with Gassmann's theory, suggests that such measurements probe undrained (saturated isobaric) conditions. Diminution or absence of such fluid‐related stiffening for low‐frequency measurements with dead volumes comparable with the pore volume of the specimen indicates partially drained conditions and highlights the critical role of experimental boundary conditions. Directly measured bulk and shear moduli are consistent with those derived from Young's modulus and Poisson's ratio. These results of the inter‐laboratory testing using different measurement devices are consistent in terms of the effect of frequency and fluid saturation for the reservoir sandstone specimen. Such broad consistency illustrates the validity of forced‐oscillation techniques and constitutes an important benchmarking of laboratory testing of the elastic properties of a porous medium. [ABSTRACT FROM AUTHOR]

Background: Tobacco smoking is one of the most important risk factors of coronary heart disease (CHD). Hence, smoking cessation is considered pivotal in the prevention of CHD. The current study aimed to evaluate smoking cessation patterns and determine factors associated with smoking cessation in patients with established CHD.Methods: The fourth European Survey of Cardiovascular Disease Prevention and Diabetes investigated quality of CHD care in 24 countries across Europe in 2012/13. In the German subset, smoking cessation patterns and clinical characteristics were repetitively assessed a) during index event due to CHD by medical record abstraction, b) as part of a face-to-face interview 6 to 36 months after the index event (i.e. baseline visit), and c) by telephone-based follow-up interview two years after the baseline visit. Logistic regression analysis was performed to search for factors determining smoking status at the time of the telephone interview.Results: Out of 469 participants available for follow-up, 104 (22.2%) had been classified as current smokers at the index event. Of those, 65 patients (62.5%) had quit smoking at the time of the telephone interview, i.e., after a median observation period of 3.5 years (quartiles 3.0, 4.1). Depressed mood at baseline visit and higher education level were less prevalent amongst quitters vs non-quitters (17.2% vs 35.9%, p = 0.03 and 15.4% vs 33.3%, p = 0.03), cardiac rehabilitation programs were more frequently attended by quitters (83.1% vs 48.7%, p < 0.001), and there was a trend for a higher prevalence of diabetes at baseline visit in quitters (37.5% vs 20.5%, p = 0.07). In the final multivariable model, cardiac rehabilitation was associated with smoking cessation (OR 5.19; 95%CI 1.87 to 14.46; p = 0.002).Discussion: Attending a cardiac rehabilitation program after a cardiovascular event was associated with smoking cessation supporting its use as a platform for smoking cessation counseling and relapse prevention. [ABSTRACT FROM AUTHOR]