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Abstract: Recently, it has been demonstrated that a shearing type interferometer, using precision silicon gratings, enables one to image the gradient of neutron phase shift through an object and retrieve the phase via a simple one-dimensional integration of the gradient. To fully explore this new technique for potential future cold neutron imaging stations at the National Institute of Standards and Technology and the Korea Atomic Energy Research Institute, we have developed a prototype phase imaging station at a monochromatic cold neutron beamline in the NCNR neutron guide hall. We have designed the silicon gratings for a neutron wavelength of 0.44nm and fabricated them using the state-of-the-art nanofabrication facility at the NIST Center for Nanoscale Science and Technology. Here we will discuss the experimental apparatus, as well as the recent experimental results obtained with this prototype apparatus. We will also present the data analysis method used for the phase retrieval, and discuss the accuracy of the method as well as the measurement sensitivity obtained using this method. [Copyright &y& Elsevier]

Background: Laparoendoscopic single-site surgery (LESS) has gained popularity in urology over the last few years., Objective: To report a large multi-institutional worldwide series of LESS in urology., Design, Setting, and Participants: Consecutive cases of LESS done between August 2007 and November 2010 at 18 participating institutions were included in this retrospective analysis., Intervention: Each group performed a variety of LESS procedures according to its own protocols, entry criteria, and techniques., Measurements: Demographic data, main perioperative outcome parameters, and information related to the surgical technique were gathered and analyzed. Conversions to reduced-port laparoscopy, conventional laparoscopy, or open surgery were evaluated, as were intraoperative and postoperative complications., Results and Limitations: Overall, 1076 patients were included in the analysis. The most common procedures were extirpative or ablative operations in the upper urinary tract. The da Vinci robot was used to operate on 143 patients (13%). A single-port technique was most commonly used and the umbilicus represented the most common access site. Overall, operative time was 160±93 min and estimated blood loss was 148±234 ml. Skin incision length at closure was 3.5±1.5 cm. Mean hospital stay was 3.6±2.7 d with a visual analog pain score at discharge of 1.5±1.4. An additional port was used in 23% of cases. The overall conversion rate was 20.8%; 15.8% of patients were converted to reduced-port laparoscopy, 4% to conventional laparoscopy/robotic surgery, and 1% to open surgery. The intraoperative complication rate was 3.3%. Postoperative complications, mostly low grade, were encountered in 9.5% of cases., Conclusions: This study provides a global view of the evolution of LESS in the field of minimally invasive urologic surgery. A broad range of procedures have been effectively performed, primarily in the academic setting, within diverse health care systems around the world. Since LESS is performed by experienced laparoscopic surgeons, the risk of complications remains low when stringent patient-selection criteria are applied., (Copyright © 2011 European Association of Urology. Published by Elsevier B.V. All rights reserved.)