Characterizing extremal digraphs for identifying codes and extremal cases of Bondy's theorem on induced subsets

An identifying code of a (di)graph $G$ is a dominating subset $C$ of the vertices of $G$ such that all distinct vertices of $G$ have distinct (in)neighbourhoods within $C$. In this paper, we classify all finite digraphs which only admit their whole vertex set in any identifying code. We also classify all such infinite oriented graphs. Furthermore, by relating this concept to a well known theorem of A. Bondy on set systems we classify the extremal cases for this theorem

Narrative medicine as a means of training medical students toward residency competencies

Objective: This study sought to explore the perceived influence of narrative medicine training on clinical skill development of fourth-year medical students, focusing on competencies mandated by ACGME and the RCPSC in areas of communication, collaboration, and professionalism. Methods: Using grounded-theory, three methods of data collection were used to query twelve medical students participating in a one-month narrative medicine elective regarding the process of training and the influence on clinical skills. Iterative thematic analysis and data triangulation occurred. Results: Response rate was 91% (survey), 50% (focus group) and 25% (follow-up). Five major findings emerged. Students perceive that they: develop and improve specific communication skills; enhance their capacity to collaborate, empathize, and be patient-centered; develop personally and professionally through reflection. They report that the pedagogical approach used in narrative training is critical to its dividends but misunderstood and perceived as counter-culture. Conclusion/Practice implications: Participating medical students reported that they perceived narrative medicine to be an important, effective, but counter-culture means of enhancing communication, collaboration, and professional development. The authors contend that these skills are integral to medical practice, consistent with core competencies mandated by the ACGME/RCPSC, and difficult to teach. Future research must explore sequelae of training on actual clinical performance. © 2013 Elsevier Ireland Ltd

Dignity and Narrative Medicine

Critiques of the dehumanising aspects of contemporary medical practice have generated increasing interest in the ways in which health care can foster a holistic sense of wellbeing. We examine the relationship between two areas of this humanistic endeavour: narrative and dignity. This paper makes two simple arguments that are intuitive but have not yet been explored in detail: that narrative competence of carers is required for maintaining or recreating dignity, and that dignity promotion in health care practice is primarily narrative in form. The multiple meanings that dignity has in a person’s life are what give the concept power and can only be captured by narrative. This has implications for health care practice where narrative work will be increasingly required to support patient dignity in under-resourced and over-subscribed health care system

Fiber-Flux Diffusion Density for White Matter Tracts Analysis: Application to Mild Anomalies Localization in Contact Sports Players

We present the concept of fiber-flux density for locally quantifying white matter (WM) fiber bundles. By combining scalar diffusivity measures (e.g., fractional anisotropy) with fiber-flux measurements, we define new local descriptors called Fiber-Flux Diffusion Density (FFDD) vectors. Applying each descriptor throughout fiber bundles allows along-tract coupling of a specific diffusion measure with geometrical properties, such as fiber orientation and coherence. A key step in the proposed framework is the construction of an FFDD dissimilarity measure for sub-voxel alignment of fiber bundles, based on the fast marching method (FMM). The obtained aligned WM tract-profiles enable meaningful inter-subject comparisons and group-wise statistical analysis. We demonstrate our method using two different datasets of contact sports players. Along-tract pairwise comparison as well as group-wise analysis, with respect to non-player healthy controls, reveal significant and spatially-consistent FFDD anomalies. Comparing our method with along-tract FA analysis shows improved sensitivity to subtle structural anomalies in football players over standard FA measurements

Clocking the Lyme Spirochete

In order to clear the body of infecting spirochetes, phagocytic cells must be able to get hold of them. In real-time phase-contrast videomicroscopy we were able to measure the speed of Borrelia burgdorferi (Bb), the Lyme spirochete, moving back and forth across a platelet to which it was tethered. Its mean crossing speed was 1,636 µm/min (N = 28), maximum, 2800 µm/min (N = 3). This is the fastest speed recorded for a spirochete, and upward of two orders of magnitude above the speed of a human neutrophil, the fastest cell in the body. This alacrity and its interpretation, in an organism with bidirectional motor capacity, may well contribute to difficulties in spirochete clearance by the host

The thing about pain: The remaking of illness narratives in chronic pain expressions on social media

In this article, we analyse chronic pain narratives on Flickr and Tumblr. We focus on how, by incorporating visual and multimodal elements, chronic pain expressions in social media significantly extend and challenge the logic, function and effects of traditional ‘illness narratives’. We examine a sample of images and blogs related to chronic pain and formulate a typology of chronic pain expressions on these sites. Flickr brings a form of narrative immediacy, making the pain experience visible, eliciting empathy and marking chronicity. Tumblr lends itself to more networked forms of interaction through the circulation of multimodal memes, and support communities are built through humour and social criticism. We argue that new forms of mediation and social media dynamics transform pain narratives. This has implications for our understandings of the forms and formats of pain communication and offers new possibilities for communicating pain within and beyond clinical contexts