Flight tests of a radar scattering-coefficient measuring instrument. Part 1 - Summary

Flight tests of radar scattering coefficient measuring instrumen

X-band scattering measurements of earth surfaces from an aircraft

Airborne equipment for measuring X band scattering of earth surface

Ectopic Sequestered Thyroid Tissue: An Unusual Cause of a Mediastinal Mass

An 80-year-old female presented with an incidental finding of a retrosternal mass on magnetic resonance imaging. Ultrasound demonstrated a mediastinal lesion adjacent to but separate from the inferior pole of the right thyroid lobe. Fine needle aspiration cytology demonstrated colloid and follicular cells. At surgery, the right thyroid lobe was found to be normal. A discrete 5 cm nodule was found in the anterior mediastinum separate from the thyroid and just anterior and to the right of the trachea and thymus. The nodule had a vascular pedicle arising from the mediastinum. The differential diagnosis included metastatic thyroid carcinoma. Histology was consistent with a benign ectopic sequestered thyroid nodule. Extensive investigations demonstrated no sign of a thyroid malignancy

Neural Structures within Human Meniscofemoral Ligaments: A Cadaveric Study.

Aim. To investigate the existence of neural structures within the meniscofemoral ligaments (MFLs) of the human knee. Methods. The MFLs from 8 human cadaveric knees were harvested. 5 μm sections were H&E-stained and examined under light microscopy. The harvested ligaments were then stained using an S100 monoclonal antibody utilising the ABC technique to detect neural components. Further examination was performed on 60–80 nm sections under electron microscopy. Results. Of the 8 knees, 6 were suitable for examination. From these both MFLs existed in 3, only anterior MFLs were present in 2, and an isolated posterior MFL existed in 1. Out of the 9 MFLs, 4 demonstrated neural structures on light and electron microscopy and this was confirmed with S100 staining. The ultrastructure of these neural components was morphologically similar to mechanoreceptors. Conclusion. Neural structures are present in MFLs near to their meniscal attachments. It is likely that the meniscofemoral ligaments contribute not only as passive secondary restraints to posterior draw but more importantly to proprioception and may therefore play an active role in providing a neurosensory feedback loop. This may be particularly important when the primary restraint has reduced function as in the posterior cruciate ligament—deficient human knee

A Method to Determine the In-Air Spatial Spread of Clinical Electron Beams

We propose and analyze in detail a method to measure the in-air spatial spread parameter of clinical electron beams. Measurements are performed at the center of the beam and below the adjustable collimators sited in asymmetrical configuration in order to avoid the distortions due to the presence of the applicator. The main advantage of our procedure lies in the fact that the dose profiles are fitted by means of a function which includes, additionally to the Gaussian step usually considered, a background which takes care of the dose produced by different mechanisms that the Gaussian model does not account for. As a result, the spatial spread is obtained directly from the fitting procedure and the accuracy permits a good determination of the angular spread. The way the analysis is done is alternative to that followed by the usual methods based on the evaluation of the penumbra width. Besides, the spatial spread found shows the quadratic-cubic dependence with the distance to the source predicted by the Fermi-Eyges theory. However, the corresponding values obtained for the scattering power are differing from those quoted by ICRU nr. 35 by a factor ~2 or larger, what requires of a more detailed investigation.Comment: 11 pages, 5 Postscript figures, to be published in Medical Physic