This work presents an investigation into the use of PRESAGE ™ dosimeters with an optical-CT scanner as a 3D dosimetry system for quantitative verification of respiratory-gated treatments. The CIRS dynamic thorax phantom was modified to incorporate a moving PRESAGE ™ dosimetersimulating respiration motion in the lungs. A simple AP/PA lung treatment plan was delivered three times to the phantom containing a different but geometrically identical PRESAGE ™ insert each time. Each delivery represented a treatment scenario: static, motion (free-breathing) and gated. The dose distributions, in the three dosimeters, were digitized by the optical-CT scanner. Improved optical-CT readout yielded an increased signal-to-noise ratio by a factor of 3 and decreased reconstruction artifacts compared with prior work. Independent measurements of dose distributions were obtained in the central plane using EBT film. Dose distributions were normalized to a point corresponding to the 100% isodose region prior to the measurement of dose profiles and gamma maps. These measurements were used to quantify the agreement between measured and ECLIPSE ® dose distributions. Average gamma pass rates between PRESAGE ™ and EBT were >99% (criteria 3% dose difference and 1.2 mm distance-to-agreement) for all three treatments. Gamma pass rates between PRESAGE ™ and ECLIPSE ® 3D dose distributions showed excellent agreement for the gated treatment (100% pass rate), but poor for the motion scenario (85% pass rate). This work demonstrates the feasibility of using PRESAGE ™ /optical-CT 3D dosimetry to verify gating-enabled radiation treatments. The capability of the Varian gating system to compensate for motion in this treatment scenario was demonstrated.
Background Adipose and adipose derived regenerative cells (ADRCs) play an increasing role in androgenetic alopecia. Objectives The authors sought to evaluate the safety and feasibility of fat grafts enriched with ADRCs in early androgenetic alopecia. Methods Seventy-one patients were treated: 16 with Puregraft fat and 1.0 × 106 ADRCs/cm2 scalp; 22 with Puregraft fat and 0.5 × 106 ADRCs/cm2 scalp, 24 with Puregraft fat alone, and 9 with saline control. Treatments were delivered into the skin and subcutaneous layer of the scalp. A total of 40 cm2 of scalp was treated and macrophotography and global photography were obtained at baseline and at 6, 24, and 52 weeks. Results A total of 71 patients tolerated the procedures well. No unanticipated associated adverse events were reported. When evaluating all patients at 24 weeks, there were no statistical differences between any of the treatment groups with respect to nonvellus (terminal) hair counts or width. There were increases (mean change from baseline) in terminal hair count for the low-dose ADRC group in the Norwood Hamilton 3 subgroup at week 6 (13.90 ± 16.68), week 12 (11.75 ± 19.42), week 24 (16.56 ± 14.68), and week 52 (2.78 ± 16.15). For this subgroup, the difference in hair count between the low-dose ADRC group and no-fat saline control was statistically significant (P = 0.0318) at week 24. Conclusions Puregraft fat and ADRCs are safe and well tolerated. In early male hair loss, this therapy demonstrated a statistically significant increase in terminal hair counts relative to the control population at 24 weeks and represents a promising approach for early androgenetic alopecia. Level of Evidence: 2
We measured the emission of water vapor at a wavelength of 1.35 centimeters from nine sources with the 120-foot (36.5-meter) Haystack antenna. Eight sources lie within 30 seconds of arc of the hydroxyl sources of 18 centimeters but not all hydroxyl sources produced detectable emission of water vapor. All sources are smaller than 30 seconds of arc in angular diameter, but we resolved at least three separate sources in the Orion Nebula. We do not find that the known hyperfine components are present with the equilibrium intensity distribution.
There is a continued need for efficient reflective and anti-reflection (AR) coatings for increasingly large optics in astronomy. The requirements for these coatings differ in several respects from those developed for commercial use. In general, they require a broad spectral coverage, high-efficiency, long life under semi-exposed conditions, and the ability to be removed without damage to expensive substrates. UCO/Lick Observatory has undertaken an effort to develop improved coatings for astronomical optics. In this paper, we report on progress toward (a) robust protected silver coatings for telescopes; (b) enhanced silver and aluminum coatings for instruments; and (c) hardened sol-gel AR coatings. Examples of some of our new coatings are in use at Lick and Keck Observatories. The problems involved in successful coatings are multifaceted and we summarize our major findings to date. This includes our requirements, test procedures, and performance and durability results for the three types of coatings mentioned.
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