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A modern operating room (OR) provides a plethora of advanced medical devices. In order to better facilitate the information offered by them, they need to automatically react to the intra-operative context. To this end, the progress of the surgical workflow must be detected and interpreted, so that the current status can be given in machine-readable form. In this work, Random Forests (RF) and Hidden Markov Models (HMM) are compared and combined to detect the surgical workflow phase of a laparoscopic cholecystectomy. Various combinations of data were tested, from using only raw sensor data to filtered and augmented datasets. Achieved accuracies ranged from 64% to 72% for the RF approach, and from 80% to 82% for the combination of RF and HMM., Comment: 7 pages, 4 figures

Purpose: We propose a mathematical framework for quantitative analysis weighting the impact of heterogeneous components of a surgery. While multi-level approaches, surgical process modeling and other workflow analysis methods exist, this is to our knowledge the first quantitative approach. Methods: Inspired by the group decision making problem from the field of operational research, we define event impact factors, which combine independent and very diverse low-level functions. This allows us to rate surgical events by their importance. Results: We conducted surveys with 4 surgeons to determine the importance of roles, phases and their combinations within a laparoscopic cholecystectomy. Applying this data on a recorded surgery, we showed that it is possible to define a quantitative measure for deciding on acception or rejection of calls to different roles and at different phases of surgery. Conclusions: This methodology allows us to use components such as expertise and role of the surgical staff and other aspects of a given surgery in order to quantitatively analyze and evaluate events, actions, user interfaces or procedures., Comment: 13 pages, 3 figures

In this technical report we present our collected dataset of laparoscopic cholecystectomies (LapChole). Laparoscopic videos of a total of 20 surgeries were recorded and annotated with surgical phase labels, of which 15 were randomly pre-determined as training data, while the remaining 5 videos are selected as test data. This dataset was later included as part of the M2CAI 2016 workflow detection challenge during MICCAI 2016 in Athens., Comment: 5 pages, 2 figures, preliminary reference for published dataset (until larger comparison study of workshop organizers is published)

Although the Thermal Infrared Sensor 2 (TIRS-2) is a nearidentical copy of the Landsat 8/TIRS-1 instrument, an important design change to the optical system was designed to mitigate the stray light issue that plagued the TIRS-1 instrument [1, 2, 3]. This change involved the addition of several baffles strategically placed within the optical telescope to block the stray light paths that were present in the TIRS- 1 design. The specific optical changes were determined by first characterizing the TIRS-1 stray light paths on-orbit and then deriving a detailed optical model that was used to determine the locations and shapes of the mitigating baffles. The stray light design changes to the TIRS-2 instrument were confirmed through the initial thermal-vacuum characterization tests. Preliminary assessments of TIRS-2 indicate that the total stray light magnitude has been drastically reduced to a total magnitude of approximately 1% or less.

A professor of sociology and anthropology chronicles the development of a course in environmental problems, beginning with inquiry into the issues and culminating in design of a course focused on research and discussion rather than lectures. Students responded positively to the exploration of multiple perspectives, particularly those at the extremes of the continuum. (MSE)

Event-related potentials (ERPs) of five- to seven-year-old girls were measured while the girls performed a visual selective attention task and a Piagetian conservation task. Results suggested more anterior ERP sources for nonconservers than conservers during early stimulus analysis, and more lateralized ERP sources for conservers than nonconservers during later information processing. (BC)

The Optical Navigation Camera (ONC) is a technical demonstration slated to fly on NASA"s Mars Reconnaissance Orbiter in 2005. Conventional navigation methods have reduced accuracy in the days immediately preceding Mars orbit insertion. The resulting uncertainty in spacecraft location limits rover landing sites to relatively safe areas, away from interesting features that may harbor clues to past life on the planet. The ONC will provide accurate navigation on approach for future missions by measuring the locations of the satellites of Mars relative to background stars. Because Mars will be a bright extended object just outside the camera"s field of view, stray light control at small angles is essential. The ONC optomechanical design was analyzed by stray light experts and appropriate baffles were implemented. However, stray light testing revealed significantly higher levels of light than expected at the most critical angles. The primary error source proved to be the interface between ground glass surfaces (and the paint that had been applied to them) and the polished surfaces of the lenses. This paper will describe troubleshooting and correction of the problem, as well as other lessons learned that affected stray light performance.

This paper describes a 12-channel infrared radiometer with the acronym SABER (Sounding of the Atmosphere using Broadband Emission radiometry) that has been selected by NASA to fly on the TIMED (Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics) mission.