120 research outputs found

    Open surgery in VR: Inguinal hernia repair according to Lichtenstein

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    VREST (Virtual Reality Educational Surgical Tools) is developing a universal and\ud autonomous simulation platform which can be used for training and assessment of\ud medical students and for continuing education of physicians. A workstation\ud consisting of two haptic devices and a 3D vision system is part of the VREST\ud platform. Another part of the platform is a generic software environment in which lessons can be built by the teacher and performed by their students. Using the platform one can see, feel and decide as in reality. With the assessment tool the progress and skills of the students can be supervised. The first lesson build on the VREST platform is an inguinal hernia repair according to Lichtenstein. This is an open surgery procedure. The VREST platform is used prior to the first operating room surgery of the resident. Interactive models and case dependant feedback is used to enlarge the residents’ cognition. This should reduce the training time in the operating room

    On the Association of γ\gamma-Ray Bursts with Supernovae

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    The recent discovery of a supernova (SN 1998bw) seemingly associated with GRB~980425 adds a new twist to the decades-old debate over the origin of gamma-ray bursts. To investigate the possibility that some (or all) bursts are associated with supernovae, we performed a systematic search for temporal/angular correlations using catalogs of BATSE and BATSE/{\it Ulysses} burst locations. We find no associations with any of the precise BATSE/ Ulysses locations, which allows us to conclude that the fraction of high-fluence gamma-ray bursts associated with known supernovae is small (<<0.2%). For the more numerous weaker bursts, the corresponding limiting fraction of 2.5% is far less constraining due to the imprecise locations of these events. This fraction (2.5%) of bursts corresponds to ∼\sim30% of the recent supernovae used as a comparison data set. Thus, although we find no significant evidence to support a burst/supernova association, the possibility cannot be excluded for weak bursts

    Validation of open-surgery VR trainer

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    VREST (Virtual Reality Educational Surgical Tools) is developing a universal and\ud autonomous simulation platform which can be used for training and assessment of\ud medical students and for continuing education of physicians. With the VREST -\ud Virtual Lichtenstein Trainer, simulating the open surgery procedure of the inguinal hernia repair according to Lichtenstein, the validation of the simulator is ongoing. Part of this trajectory is the evaluation of the transfer of training of the virtual incision making. One group of students trained incision making on the VREST platform where the control group did not. In an experiment both groups has to perform several incision tasks on a manikin. The results are not available yet but will be presented at the MMVR14 conference

    On the nature of XTE J0421+560/CI Cam

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    We present the results of the analysis of RXTE, BATSE and optical/infrared data of the 1998 outburst of the X-ray transient system XTE J0421+560 (CI Cam). The X-ray outburst shows a very fast decay (initial e-folding time ~0.5 days, slowing down to ~2.3 days). The X-ray spectrum in the 2-25 keV band is complex, softening considerably during decay and with strongly variable intrinsic absorption. A strong iron emission line is observed. No fast time variability is detected (<0.5 % rms in the 1-4096 Hz band at the outburst peak). The analysis of the optical/IR data suggests that the secondary is a B[e] star surrounded by cool dust and places the system at a distance of >~ 2 kpc. At this distance the peak 2-25 keV luminosity is ~4 x 10^37 erg/s. We compare the properties of this peculiar system with those of the Be/NS LMC transient A 0538-66 and suggest that CI Cam is of similar nature. The presence of strong radio emission during outburst indicates that the compact object is likely to be a black hole or a weakly magnetized neutron star.Comment: Accepted for publication on The Astrophysical Journal, July 199

    Chandra and RXTE Spectroscopy of the Galactic Microquasar XTE J1550-564 in Outburst

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    On two occasions, we obtained nearly simultaneous ~ 4 kilosecond snapshot observations of the Galactic black hole and microquasar XTE J1550-564 with Chandra and RXTE near the peak of its May, 2000 outburst. The low-energy sensitivity of Chandra and the resolution of the High Energy Transmission Grating Spectrometer (HETGS), coupled with the broad energy range and large collecting area of RXTE, have allowed us to place constraints on the outburst accretion flow geometry of this source in the ``intermediate'' X-ray state. The 0.65-25.0 keV continuum spectra are well-described by relatively hot (kT ~ 0.8 keV) accretion disk and hard (Gamma ~ 2.3) coronal power-law components. Broad, relatively strong Fe K-alpha emission line (EW ~170 eV) and smeared absorption edge components consistent with Fe XXV are strongly required in joint spectral fits. The resolution of the Chandra/HETGS reveals that the broad Fe K-alpha emission lines seen clearly in the individual RXTE spectra are not due to an intrinsically narrow line.Comment: 11 pages, 4 figures (2 in color). MNRAS, accepted. Significant updates from the initial versio

    Human Rights and American Foreign Policy

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    A collection of articles examines the human rights thrust of President Carter\u27s foreign policy, considering its formation, definition, difficulties, and implementation and evaluating its political and moral overtoneshttps://scholarship.law.nd.edu/law_books/1066/thumbnail.jp

    Human Rights and American Foreign Policy

    No full text
    A collection of articles examines the human rights thrust of President Carter\u27s foreign policy, considering its formation, definition, difficulties, and implementation and evaluating its political and moral overtoneshttps://scholarship.law.nd.edu/law_books/1066/thumbnail.jp
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