A coupled finite-volume CFD solver for two-dimensional elasto-hydrodynamic lubrication problems with particular application to rolling element bearings

This paper describes a new computational fluid dynamics methodology for modelling elastohydrodynamic contacts. A finite-volume technique is implemented in the ‘OpenFOAM’ package to solve the Navier-Stokes equations and resolve all gradients in a lubricated rolling-sliding contact. The method fully accounts for fluid-solid interactions and is stable over a wide range of contact conditions, including pressures representative of practical rolling bearing and gear applications. The elastic deformation of the solid, fluid cavitation and compressibility, as well as thermal effects are accounted for. Results are presented for rolling-sliding line contacts of an elastic cylinder on a rigid flat to validate the model predictions, illustrate its capabilities, and identify some example conditions under which the traditional Reynolds-based predictions deviate from the full CFD solution

Consumption of spicy foods and the prevalence of irritable bowel syndrome

AimTo explore the association between consumption of spicy foods and prevalence of irritable bowel syndrome (IBS) among Iranian adults.MethodsIn this cross-sectional study, data from 4763 Iranian adult participants were used. Consumption of spicy foods was estimated using a dietary habits questionnaire that included a question on spicy foods consumption: "how frequently do you use spicy foods (pepper, curry, ginger, cinnamon and turmeric) during a week?" Participants could respond to the question by choosing one of these choices: never, 1-3 times, 4-6 times, 7-9 times, or more than 10 times per week. A modified Persian version of the Rome III questionnaire was used to determine the prevalence of IBS.ResultsIBS was prevalent in 21.7% (18.6% of men and 24.1% of women) of the study population. After controlling for potential confounders including dietary behaviors, those consuming spicy foods ≥ 10 times per week were 92% more likely to have IBS compared with those who never consumed spicy foods (OR = 1.92; 95%CI: 1.23-3.01, P trend ConclusionConsumption of spicy foods is directly associated with IBS, particularly in women. Further, prospective studies are warranted to (1) examine this association in other populations; and (2) evaluate whether dietary interventions, for example a reduction in spice consumption, would improve IBS symptoms.Ahmad Esmaillzadeh, Ammar Hassanzadeh Keshteli, Maryam Hajishafiee, Awat Feizi, Christine Feinle-Bisset and Peyman Adib

Association between healthy lifestyle score and upper gastrointestinal disorders in Iranian adults

Background and Objective: Although lifestyle-related factors have separately been examined in relation to functional gastrointestinal disorders (FGIDs), there is no epidemiologic data on the combined association of lifestyle factors with these conditions. We aimed to examine how combinations of several lifestyle factors were associated with functional dyspepsia (FD), its symptoms and gastro-esophageal reflux disease (GERD) in a large group of Iranian adults. Methods: This descriptive -analytic study was conducted on 3363 Iranian adults (19-70 yr), whom were working in 50 health centers across Isfahan province in Iran during 2012. We used easy non-random sampling to select participants. The “healthy lifestyle score” for each participant was calculated by summing up the binary score given for five lifestyle factors, including dietary habits, dietary intakes, psychological distress, smoking and physical activity. A dish-based 106-item semi-quantitative validated food frequency questionnaire, General Practice Physical Activity Questionnaire, General Health Questionnaire and other pre-tested questionnaires were used to assess the components of healthy lifestyle score. A validated Persian version of ROME III questionnaire was used, to assess functional gastrointestinal disorders. Results: The prevalence of FD and GERD among study participants was 14.5 and 23.6%, respectively. After adjustment for potential confounders, we found that individuals with the highest score of healthy lifestyle had 79 and 74% lower odds of FD (95% CI: 0.05-0.92, OR: 0.21, P=0.03) and GERD (95% CI: 0.09-0.69, OR: 0.26, P=0.01), respectively, compared with those with the lowest score. They were also less likely to have early satiation (95% CI: 0.11-0.73, OR: 0.28, P=0.001), postprandial fullness (95% CI: 0.09-0.50, OR: 0.22, P<0.001) and epigastric pain (95% CI: 0.21-0.92, OR: 0.44, P=0.03). In addition to the combined healthy lifestyle score, low levels of psychological distress, a healthy diet, healthy dietary habits and non-smoking were separately associated with FGIDs (P<0.05). Conclusion: This study showed that adherence to a healthy lifestyle was associated with lower odds of GERD, FD and its symptoms in this group of Iranian adults. Individual lifestyle-related factors were also associated with these conditions