A parent-centered radial layout algorithm for interactive graph visualization and animation

We have developed (1) a graph visualization system that allows users to explore graphs by viewing them as a succession of spanning trees selected interactively, (2) a radial graph layout algorithm, and (3) an animation algorithm that generates meaningful visualizations and smooth transitions between graphs while minimizing edge crossings during transitions and in static layouts. Our system is similar to the radial layout system of Yee et al. (2001), but differs primarily in that each node is positioned on a coordinate system centered on its own parent rather than on a single coordinate system for all nodes. Our system is thus easy to define recursively and lends itself to parallelization. It also guarantees that layouts have many nice properties, such as: it guarantees certain edges never cross during an animation. We compared the layouts and transitions produced by our algorithms to those produced by Yee et al. Results from several experiments indicate that our system produces fewer edge crossings during transitions between graph drawings, and that the transitions more often involve changes in local scaling rather than structure. These findings suggest the system has promise as an interactive graph exploration tool in a variety of settings

Collaborative innovation program: A Creative conspiracy for cross-college collaboration at the Rochester Institute of Technology

The 2007 inaugural address of RIT’s ninth president, William Destler, highlighted the breadth and diversity of curricular offerings at RIT from business, engineering, and computing to design, fine art, and craft. In his address, Dr. Destler included this challenge: “What if RIT students [in addition to their discipline-specific courses] had the experience of working on complex societal problems with students from different majors on teams in...a cross-disciplinary effort to find real solutions?” The authors of this paper took that challenge to heart. In the 2008- 2009 academic year, we wrote and taught a collaboration curriculum that was hosted by the RIT Honors program but open to all RIT students. The outcome of this program is an integrated “innovation suite” comprised of the following components: 1. learning outcomes and curricular models for innovation, 2. innovation activities, 3. collaborative learning environments, 4. collaborative technologies (IT and other), and 5. community-university partnerships. This integrated suite of innovation components will continue to grow in the new Center for Student Innovation at RIT

Teaching and learning innovation and invention

Each quarter at Rochester Institute of Technology (RIT), our course on innovation and invention gathers undergraduate and graduate students from as many disciplines as possible and attempts to do something none of us (including the instructors) knows how to do. Our methodology, modeled after business startups more than traditional academic courses, produces interesting inventions and remarkable learning experiences. We will report on the first four offerings of this course at RIT, and speculate on why it works as well as it does. Class begins by presenting students with a stimulating but vague challenge that can engage all the participants (e.g., “build a multi-person multimedia computer that surrounds people”) and then mapping and connecting students’ interests and expertise. Sub-projects form, develop, die and/or expand, through student collaboration and peer problem solving, as the class pushes toward an ultimate deliverable in which all participants can feel ownership and pride. Relatively unstructured and unpredictable multidisciplinary problem solving experiences can complement traditionally structured and predictable intra-disciplinary curricula. By collaborating across disciplines, students can deepen their understanding and broaden the application of hard-won discipline-specific knowledge and expertise. They can also learn to enjoy and endure the fine art of improvisational innovation and invention

The impact of delays to admission from the emergency department on inpatient outcomes

<p>Abstract</p> <p>Background</p> <p>We sought to determine the impact of delays to admission from the Emergency Department (ED) on inpatient length of stay (LOS), and IP cost.</p> <p>Methods</p> <p>We conducted a retrospective analysis of 13,460 adult (≥ 18 yrs) ED visits between April 1 2006 and March 30 2007 at a tertiary care teaching hospital with two ED sites in which the mode of disposition was admission to ICU, surgery or inpatient wards. We defined ED Admission Delay as ED time to decision to admit > 12 hours. The primary outcomes were IP LOS, and total IP cost.</p> <p>Results</p> <p>Approximately 11.6% (n = 1558) of admitted patients experienced admission delay. In multivariate analysis we found that admission delay was associated with 12.4% longer IP LOS (95% CI 6.6% - 18.5%) and 11.0% greater total IP cost (6.0% - 16.4%). We estimated the cumulative impact of delay on all delayed patients as an additional 2,183 inpatient days and an increase in IP cost of $2,109,173 at the study institution.</p> <p>Conclusions</p> <p>Delays to admission from the ED are associated with increased IP LOS and IP cost. Improving patient flow through the ED may reduce hospital costs and improve quality of care. There may be a business case for investments to reduce emergency department admission delays.</p

Prospective Validation of the Emergency Heart Failure Mortality Risk Grade for Acute Heart Failure: The ACUTE Study

Background: Improved risk stratification of acute heart failure in the emergency department may inform physicians\u27 decisions regarding patient admission or early discharge disposition. We aimed to validate the previously-derived Emergency Heart failure Mortality Risk Grade for 7-day (EHMRG7) and 30-day (EHMRG30-ST) mortality. Methods: We conducted a multicenter, prospective validation study of patients with acute heart failure at 9 hospitals. We surveyed physicians for their estimates of 7-day mortality risk, obtained for each patient before knowledge of the model predictions, and compared these with EHMRG7 for discrimination and net reclassification improvement. We also prospectively examined discrimination of the EHMRG30-ST model, which incorporates all components of EHMRG7 as well as the presence of ST-depression on the 12-lead ECG. Results: We recruited 1983 patients seeking emergency department care for acute heart failure. Mortality rates at 7 days in the 5 risk groups (very low, low, intermediate, high, and very high risk) were 0%, 0%, 0.6%, 1.9%, and 3.9%, respectively. At 30 days, the corresponding mortality rates were 0%, 1.9%, 3.9%, 5.9%, and 14.3%. Compared with physician-estimated risk of 7-day mortality (PER7; c-statistic, 0.71; 95% CI, 0.64-0.78) there was improved discrimination with EHMRG7 (c-statistic, 0.81; 95% CI, 0.75-0.87; P=0.022 versus PER7) and with EHMRG7 combined with physicians\u27 estimates (c-statistic, 0.82; 95% CI, 0.76-0.88; P=0.003 versus PER7). Model discrimination increased nonsignificantly by 0.014 (95% CI, -0.009-0.037) when physicians\u27 estimates combined with EHMRG7 were compared with EHMRG7 alone (P=0.242). The c-statistic for EHMRG30-ST alone was 0.77 (95% CI, 0.73-0.81) and 30-day model discrimination increased nonsignificantly by addition of physician-estimated risk to 0.78 (95% CI, 0.73-0.82; P=0.187). Net reclassification improvement with EHMRG7 was 0.763 (95% CI, 0.465-1.062) when assessed continuously and 0.820 (0.560-1.080) using risk categories compared with PER7. Conclusions: A clinical model allowing simultaneous prediction of mortality at both 7 and 30 days identified acute heart failure patients with a low risk of events. Compared with physicians\u27 estimates, our multivariable model was better able to predict 7-day mortality and may guide clinical decisions. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02634762