RESUMO
We present two prescriptions for broadband ($ {\sim} 77 - 252\;{\rm GHz} $), millimeter-wave antireflection coatings for cryogenic, sintered polycrystalline aluminum oxide optics: one for large-format (700 mm diameter) planar and plano-convex elements, the other for densely packed arrays of quasi-optical elements-in our case, 5 mm diameter half-spheres (called "lenslets"). The coatings comprise three layers of commercially available, polytetrafluoroethylene-based, dielectric sheet material. The lenslet coating is molded to fit the 150 mm diameter arrays directly, while the large-diameter lenses are coated using a tiled approach. We review the fabrication processes for both prescriptions, then discuss laboratory measurements of their transmittance and reflectance. In addition, we present the inferred refractive indices and loss tangents for the coating materials and the aluminum oxide substrate. We find that at 150 GHz and 300 K the large-format coating sample achieves $ (97 \pm 2)\% $ transmittance, and the lenslet coating sample achieves $ (94 \pm 3)\% $ transmittance.
RESUMO
All existing classifications, which are based on the severity of hand injuries, are being referred to facets of variety of hand injuries in general. A clear picture of all consequences of hand injuries would be apparent, if any kind of injury mechanism and occurrence of an injury would be identified and academically captured. Predictions regarding return to the former occupation and rehabilitation time would be possible with further study; 102 patients with different hand injuries were engaged in a pilot project using a specifically designed assessment sheet to achieve this purpose in the framework of a retrospective clinical testing within 1 year. Data were summarized and demonstrated graphically. Each category showed a picture of prior localization of the injury and its morphology. All categories show specific injury patterns. The choice of categories reflects the mechanisms of injury emphasized in literature. Furthermore, the mean DASH equivalents of one category were compared to the mean Hand Injury Severity Scoring (HISS) scores in order to get an initial idea of information on the degree of severity. A first impression of the potential of this assessment sheet has been obtained with regard to the above. With further study, we could evaluate the assessment sheet and try to create a classification of the grade of severity as well as prognostic values like return to the former occupation and rehabilitation time.
