Evidence for waning of latency in a cohort study of tuberculosis

<p>Abstract</p> <p>Background</p> <p>To investigate how the risk of active tuberculosis disease is influenced by time since original infection and to determine whether the risk of reactivation of tuberculosis increases or decreases with age.</p> <p>Methods</p> <p>Cohort analysis of data for the separate ten year birth cohorts of 1876-1885 to 1959-1968 obtained from Statistics Norway and the National Tuberculosis Registry. These data were used to calculate the rates and the changes in the rates of bacillary (or active) tuberculosis. Data on bacillary tuberculosis for adult (20+) age groups were obtained from the National Tuberculosis Registry and Statistics Norway from 1946 to 1974. Most cases during this period arose due to reactivation of remote infection. Participants in this part of the analysis were all reported active tuberculosis cases in Norway from 1946 to 1974 as recorded in the National Tuberculosis Registry.</p> <p>Results</p> <p>Tuberculosis decreased at a relatively steady rate when following individual birth cohorts, but with a tendency of slower decline as time passed since infection. A mean estimate of this rate of decline was 57% in a 10 year period.</p> <p>Conclusions</p> <p>The risk of reactivation of latent tuberculosis decreases with age. This decline may reflect the rate at which latent tuberculosis is eliminated from a population with minimal transmission of tubercle bacilli. A model for risk of developing active tuberculosis as a function of time since infection shows that the rate at which tuberculosis can be eliminated from a society can be quite substantial if new infections are effectively prevented. The findings clearly indicate that preventative measures against transmission of tuberculosis will be the most effective. These results also suggest that the total population harbouring live tubercle bacilli and consequently the future projection for increased incidence of tuberculosis in the world is probably overestimated.</p

Real-World Affinity Diagramming Practices Bridging the Paper-Digital Gap

Despite the availability of computer-based alternatives both for desktop and touch screen systems, a number of cooperative work processes still commonly rely on simple paper sticky notes. In this paper, we present the first in-depth investigation of the real-world practices of people who use paper-based affinity diagrams and similar clustering processes in their work, in order to identify challenges and requirements for technology support. Findings from retrospective and artifact-based interviews with 13 participants suggest ways in which the rich interactions and material affordances offered by paper are key to the process. Instead of seeking to replicate interactions with paper on a screen, simpler transfer of information between the physical and digital worlds has the potential to address many of the most pressing problems experienced in practice. We describe different types of technology integration and augmentation, with preliminary recommendations for different situations

Two Thousand Points of Interaction: Augmenting Paper Notes for a Distributed User Experience

We present two early prototypes of a system that couples an augmented wall of paper notes with multiple handheld devices in order to support the process of affinity diagramming. Our system allows multiple users to work together simultaneously, freely interacting with potentially thousands of physical notes directly, and with a coupled digital representation of the same notes via a smart phone, tablet or PC. We propose the affinity diagramming process as a use-case well suited for distributed user interfaces

Designing shared public display networks – implications from today’s paper-based notice areas

Abstract. Large public displays have become a regular conceptual element in many shops and businesses, where they advertise products or highlight upcoming events. In our work, we are interested in exploring how these isolated display solutions can be interconnected to form a single large network of public displays, thus supporting novel forms of sharing access to display real estate. In order to explore the feasibility of this vision, we investigated today’s practices surrounding shared notice areas, i.e. places where customers and visitors can put up event posters and classifieds, such as shop windows or notice boards. In particular, we looked at the content posted to such areas, the means for sharing it (i.e., forms of content control), and the reason for providing the shared notice area. Based on two-week long photo logs and a number of in-depth interviews with providers of such notice areas, we provide a systematic assessment of factors that inhibit or promote the shared use of public display space, ultimately leading to a set of concrete design implication for providing future digital versions of such public notice areas in the form of networked public displays