42 research outputs found
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CT colonography: external clinical validation of an algorithm for computer-assisted prone and supine registration
Purpose
To perform external validation of a computer-assisted registration algorithm for prone and supine computed tomographic (CT) colonography and to compare the results with those of an existing centerline method.
Materials and Methods
All contributing centers had institutional review board approval; participants provided informed consent. A validation sample of CT colonographic examinations of 51 patients with 68 polyps (6–55 mm) was selected from a publicly available, HIPAA compliant, anonymized archive. No patients were excluded because of poor preparation or inadequate distension. Corresponding prone and supine polyp coordinates were recorded, and endoluminal surfaces were registered automatically by using a computer algorithm. Two observers independently scored three-dimensional endoluminal polyp registration success. Results were compared with those obtained by using the normalized distance along the colonic centerline (NDACC) method. Pairwise Wilcoxon signed rank tests were used to compare gross registration error and McNemar tests were used to compare polyp conspicuity.
Results
Registration was possible in all 51 patients, and 136 paired polyp coordinates were generated (68 polyps) to test the algorithm. Overall mean three-dimensional polyp registration error (mean ± standard deviation, 19.9 mm ± 20.4) was significantly less than that for the NDACC method (mean, 27.4 mm ± 15.1; P = .001). Accuracy was unaffected by colonic segment (P = .76) or luminal collapse (P = .066). During endoluminal review by two observers (272 matching tasks, 68 polyps, prone to supine and supine to prone coordinates), 223 (82%) polyp matches were visible (120° field of view) compared with just 129 (47%) when the NDACC method was used (P < .001). By using multiplanar visualization, 48 (70%) polyps were visible after scrolling ± 15 mm in any multiplanar axis compared with 16 (24%) for NDACC (P < .001).
Conclusion
Computer-assisted registration is more accurate than the NDACC method for mapping the endoluminal surface and matching the location of polyps in corresponding prone and supine CT colonographic acquisitions
The development of wayfinding abilities in children: Learning routes with and without landmarks
Young children experience wayfinding difficulties. A better understanding of the development of wayfinding abilities may inform strategies that can be used to improve these skills in children. The ability to learn and remember a route was assessed in 220 6-, 8-, and 10-year old children and adults. Participants were shown a route in a virtual environment, before they were asked to retrace this route until they had achieved two consecutive trials without error. The virtual environment contained (i) no landmarks (ii) landmarks or (iii) landmarks that were verbally labelled. Adults, 10-year-olds and most 8-year-olds learnt the route when landmarks were present, but not all the 6-year-olds were successful. All age groups of children improved when the landmarks were labelled. Children were much poorer when there were no landmarks. This is the first study to distinguish between route learning dependent on landmarks, and route learning without landmarks (i.e. dependent on directions)
Decentralized clinical trials in the trial innovation network: Value, strategies, and lessons learned
New technologies and disruptions related to Coronavirus disease-2019 have led to expansion of decentralized approaches to clinical trials. Remote tools and methods hold promise for increasing trial efficiency and reducing burdens and barriers by facilitating participation outside of traditional clinical settings and taking studies directly to participants. The Trial Innovation Network, established in 2016 by the National Center for Advancing Clinical and Translational Science to address critical roadblocks in clinical research and accelerate the translational research process, has consulted on over 400 research study proposals to date. Its recommendations for decentralized approaches have included eConsent, participant-informed study design, remote intervention, study task reminders, social media recruitment, and return of results for participants. Some clinical trial elements have worked well when decentralized, while others, including remote recruitment and patient monitoring, need further refinement and assessment to determine their value. Partially decentralized, or “hybrid” trials, offer a first step to optimizing remote methods. Decentralized processes demonstrate potential to improve urban-rural diversity, but their impact on inclusion of racially and ethnically marginalized populations requires further study. To optimize inclusive participation in decentralized clinical trials, efforts must be made to build trust among marginalized communities, and to ensure access to remote technology
Guardfest \u2787, Training and Equipment Expo at Camp McCain, Mississippi
Views of Guardfest \u2787 Training and Equipment Expo at Camp McCain. Includes scenes of exhibit tents, the crowd, flying helicopters and planes, and Jamie Whitten\u27s arrival. Program includes posting of the colors; the national anthem; invocation by Chaplain Winston; unidentified officer of the Mississippi National Guard welcomes crowd, identifies platform guests and reads letters from those absent to Whitten; speech by Mayor L.D. Boone of Grenada; unidentified officer discusses Camp McCain and the dedication of its new Jamie L. Whitten Army National Training Complex; remarks by Whitten; and benediction. Unveiling of Jamie L. Whitten Army National Training Complex sign; views of paratroopers landing and a helicopter flying a supply load
Data from: Artificial light at night confounds broad-scale habitat use by migrating birds
With many of the world's migratory bird populations in alarming decline, broad-scale assessments of responses to migratory hazards may prove crucial to successful conservation efforts. Most birds migrate at night through increasingly light-polluted skies. Bright light sources can attract airborne migrants and lead to collisions with structures, but might also influence selection of migratory stopover habitat and thereby acquisition of food resources. We demonstrate, using multi-year weather radar measurements of nocturnal migrants across the northeastern U.S., that autumnal migrant stopover density increased at regional scales with proximity to the brightest areas, but decreased within a few kilometers of brightly-lit sources. This finding implies broad-scale attraction to artificial light while airborne, impeding selection for extensive forest habitat. Given that high-quality stopover habitat is critical to successful migration, and hindrances during migration can decrease fitness, artificial lights present a potentially heightened conservation concern for migratory bird populations
Development, implementation, and dissemination of operational innovations across the trial innovation network
Improving the quality and conduct of multi-center clinical trials is essential to the generation of generalizable knowledge about the safety and efficacy of healthcare treatments. Despite significant effort and expense, many clinical trials are unsuccessful. The National Center for Advancing Translational Science launched the Trial Innovation Network to address critical roadblocks in multi-center trials by leveraging existing infrastructure and developing operational innovations. We provide an overview of the roadblocks that led to opportunities for operational innovation, our work to develop, define, and map innovations across the network, and how we implemented and disseminated mature innovations