A Low-noise Micromachined Millimeter-Wave Heterodyne Mixer using Nb Superconducting Tunnel Junctions

A heterodyne mixer with a micromachined horn antenna and a superconductor-insulator-superconductor (SIS) tunnel junction as mixing element is tested in the W-band (75-115 GHz) frequency range. Micromachined integrated horn antennas consist of a dipole antenna suspended on a thin Si3N4 dielectric membrane inside a pyramidal cavity etched in silicon. The mixer performance is optimized by using a backing plane behind the dipole antenna to tune out the capacitance of the tunnel junction. The lowest receiver noise temperature of 30 +/- 3 K (without any correction) is measured at 106 GHz with a 3-dB bandwidth of 8 GHz. This sensitivity is comparable to the state-of-the-art waveguide and quasi-optical SIS receivers, showing the potential use of micromachined horn antennas in imaging arrays

Gastronet survey on the use of one- or two-person technique for colonoscopy insertion

Background Usually, colonoscopy insertion is performed by the colonoscopist (one-person technique). Quite common in the early days of endoscopy, the assisting nurse is now only rarely doing the insertion (two-person technique). Using the Norwegian national endoscopy quality assurance (QA) programme, Gastronet, we wanted to explore the extent of two-person technique practice and look into possible differences in performance and QA output measures. Methods 100 colonoscopists in 18 colonoscopy centres having reported their colonoscopies to Gastronet between January and December 2009 were asked if they practiced one- or two-person technique during insertion of the colonoscope. They were categorized accordingly for comparative analyses of QA indicators. Results 75 endoscopists responded to the survey (representing 9368 colonoscopies) - 62 of them (83%) applied one-person technique and 13 (17%) two-person technique. Patients age and sex distributions and indications for colonoscopy were also similar in the two groups. Caecal intubation was 96% in the two-person group compared to 92% in the one-person group (p < 0.001). Pain reports were similar in the groups, but time to the caecum was shorter and the use of sedation less in the two-person group. Conclusion Two-person technique for colonoscope insertion was practiced by a considerable minority of endoscopists (17%). QA indicators were either similar to or better than one-person technique. This suggests that there may be some beneficial elements to this technique worth exploring and try to import into the much preferred one-person insertion technique

Gastronet survey on the use of one- or two-person technique for colonoscopy insertion

Abstract Background Usually, colonoscopy insertion is performed by the colonoscopist (one-person technique). Quite common in the early days of endoscopy, the assisting nurse is now only rarely doing the insertion (two-person technique). Using the Norwegian national endoscopy quality assurance (QA) programme, Gastronet, we wanted to explore the extent of two-person technique practice and look into possible differences in performance and QA output measures. Methods 100 colonoscopists in 18 colonoscopy centres having reported their colonoscopies to Gastronet between January and December 2009 were asked if they practiced one- or two-person technique during insertion of the colonoscope. They were categorized accordingly for comparative analyses of QA indicators. Results 75 endoscopists responded to the survey (representing 9368 colonoscopies) - 62 of them (83%) applied one-person technique and 13 (17%) two-person technique. Patients age and sex distributions and indications for colonoscopy were also similar in the two groups. Caecal intubation was 96% in the two-person group compared to 92% in the one-person group (p Conclusion Two-person technique for colonoscope insertion was practiced by a considerable minority of endoscopists (17%). QA indicators were either similar to or better than one-person technique. This suggests that there may be some beneficial elements to this technique worth exploring and try to import into the much preferred one-person insertion technique.</p