Ultra low background cryogenic test facility for far-infrared radiation detectors

The next generation of far infrared radiation detectors is aimed to reach photon noise limited performance in space based observatories such as SPICA and BLISS. These detectors operate at loading powers of the astronomical signal of a few Attowatt (10?18 W) or less, corresponding to a sensitivity expressed in noise equivalent power as low as NEP = 2×10?20 W/? Hz. We have developed a cryogenic test setup for microwave Kinetic Inductance Detectors (MKIDs) that aims to reach these ultra-low background levels. Stray light is stopped by using a box in a box design with a sample holder inside another closed box. Microwave signals for the MKID readout enters the outer box through custom made coax cable filters. The stray light loading per pixel is estimated to be less than 60 × 10?18 W during nominal operation, a number limited by the intrinsic sensitivity of the MKIDs used to validate the system.Kavli Institute of NanoScienceApplied Science

Hypofractionation vs Conventional Radiation Therapy for Newly Diagnosed Diffuse Intrinsic Pontine Glioma: A Matched-Cohort Analysis

Item does not contain fulltextPURPOSE: Despite conventional radiation therapy, 54 Gy in single doses of 1.8 Gy (54/1.8 Gy) over 6 weeks, most children with diffuse intrinsic pontine glioma (DIPG) will die within 1 year after diagnosis. To reduce patient burden, we investigated the role of hypofractionation radiation therapy given over 3 to 4 weeks. A 1:1 matched-cohort analysis with conventional radiation therapy was performed to assess response and survival. METHODS AND MATERIALS: Twenty-seven children, aged 3 to 14, were treated according to 1 of 2 hypofractionation regimens over 3 to 4 weeks (39/3 Gy, n=16 or 44.8/2.8 Gy, n=11). All patients had symptoms for /=2 signs of the neurologic triad (cranial nerve deficit, ataxia, long tract signs), and characteristic features of DIPG on magnetic resonance imaging. Twenty-seven patients fulfilling the same diagnostic criteria and receiving at least 50/1.8 to 2.0 Gy were eligible for the matched-cohort analysis. RESULTS: With hypofractionation radiation therapy, the overall survival at 6, 9, and 12 months was 74%, 44%, and 22%, respectively. Progression-free survival at 3, 6, and 9 months was 77%, 43%, and 12%, respectively. Temporary discontinuation of steroids was observed in 21 of 27 (78%) patients. No significant difference in median overall survival (9.0 vs 9.4 months; P=.84) and time to progression (5.0 vs 7.6 months; P=.24) was observed between hypofractionation vs conventional radiation therapy, respectively. CONCLUSIONS: For patients with newly diagnosed DIPG, a hypofractionation regimen, given over 3 to 4 weeks, offers equal overall survival with less treatment burden compared with a conventional regimen of 6 weeks