The aims of this study were to assess the prevalence of Helicobacter pylori and its relationship with different epidemiological factors in an Anglo-Celtic Australian population in the Melbourne urban area. Two hundred and seventy-three (120 men and 153 women with a mean age of 55.6 and range of 20 to 80 years) of 396 eligible subjects randomly sampled from the telephone directory were studied. An ELISA technique was used to detect H. pylori immunoglobulin (Ig)G antibody and self-administered questionnaires were completed. The overall seroprevalence of H. pylori was 38% and increased with age from 18% (20-30 years old) to 53% (over 70 years; P < 0.0001). The acquisition of H. pylori infection was 1% per year. The prevalence of H. pylori was 48% in men and 30% in women (P < 0.01). The frequency of H. pylori was also associated with low-income levels and current smoking, but was not associated with peptic ulcer disease history. The prevalence of H. pylori infection in a representative Australian population was found to be similar to other developed countries. The risk factors for H. pylori infection include age, male sex, low household income and a smoking habit. No correlation between H. pylori status and dyspepsia symptoms were observed.

The work is transparent, motivates ongoing refinements, and identifies areas for improved measurements. After validation, such a model can be used to identify effective investments to enhance community resilience. (Disaster Med Public Health Preparedness. 2018;12:127-137).

This paper proposes using topology optimization to design fixed-geometry fluid diodes that allow easy passage of fluid flowing in one direction while inhibiting flow in the reverse direction. Fixed-geometry diodes do not use movable mechanical parts or deformations, but rather utilize inertial forces of the fluid to achieve this flow behavior. Diode performance is measured by diodicity, defined as the ratio of pressure drop of reverse flow and forward flow, or equivalently the ratio of dissipation of reverse and forward flow. Diodicity can then be maximized by minimizing forward dissipation while maximizing reverse dissipation. While significant research has been conducted in topology optimization of fluids for minimizing dissipation, maximizing dissipation introduces challenges in the form of small, mesh dependent flow channels and that artificial flow in solid region becomes (numerically) desirable. These challenges are circumvented herein using projection methods for controlling the minimum length scale of channels and by introducing an additional penalty term on flow through intermediate porosities. Several solutions are presented, one of which is fabricated by 3D printing and experimentally tested to demonstrate the diodelike behavior.

Systems modeling represents an innovative approach for addressing the obesity epidemic at the community level. We developed an agent-based model of the Baltimore City food environment that permits us to assess the relative impact of different programs and policies, alone and in combination, and potential unexpected consequences. Based on this experience, and a review of literature, we have identified a set of principles, potential benefits, and challenges. Some of the key principles include the importance of early and multilevel engagement with the community prior to initiating model development and continued engagement and testing with community stakeholders. Important benefits include improving community stakeholder understanding of the system, testing of interventions before implementation, and identification of unexpected consequences. Challenges in these models include deciding on the most important, yet parsimonious factors to consider, how to model food source and food selection behavior in a realistic yet transferable manner, and identifying the appropriate outcomes and limitations of the model.