Town,SouthAfrica(DrC.L.Shields); Mellon Charitable Giving from the Martha W. Rogers Charitable Trust, Philadelphia, Pennsylvania (Dr C. L. Shields); the LuEsther Mertz Retina ResearchFoundation,NewYork,New York (Dr C. L. Shields); a donation from Michael, Bruce, and Ellen Ratner, New York (Drs C. L. Shields and J.A.Shields); theEyeTumorResearch Foundation, Philadelphia (Drs C. L. ShieldsandJ.A....

Plain pelvic radiographs are commonly used for a variety of pediatric orthopedic disorders. Lead shielding is typically placed over the gonads to minimize radiation exposure to these sensitive tissues. However, misplaced shielding can sabotage efforts to protect patients from excessive radiation exposure either by not covering radiosensitive tissues or by obscuring anatomic areas of interest, p...

INTRODUCTION Positron Emission Tomography (PET) is enjoying explosive growth due to its ability to accurately stage many types of cancer and follow the progress of treatments. The facilities present unique challenges in shielding design due to the nature of the study, and the desire to place the facilities near other imaging and treatment clinics. A typical PET patient will receive 555 MBq (15 ...

In this article, a multilayer piezoelectric transformer based on lead-free Mn-doped 0.94(Bi(12)Na(12))TiO(3)-0.06BaTiO(3) ceramics is presented. This piezoelectric transformer, with a multilayered construction in the thickness direction, is 8.3 mm long, 8.3 mm wide, and 2.3 mm thick. It operates in the second thickness extensional vibration mode. For a temperature rise of 20 degrees C, the tran...

Acoustic emission (AE) sensors have been fabricated using both soft- and hard-type lead-free (Na0.5K0.5)NbO3-based ceramics. The acoustic and electromechanical properties of the ceramics have been determined using the resonance technique. The lead-free AE sensors were calibrated using a laser source and compared to a commercial sensor. A lead zirconate titanate (PZT) 5H ceramics AE sensor has a...

Collagen corneal shields were developed as a corneal bandage lens and are currently indicated for ocular surface protection following surgery and in traumatic and nontraumatic corneal conditions. Collagen shields are manufactured from porcine or bovine collagen and three different collagen shields are currently available with dissolution times of 12, 24, and 72 hours. The theoretical, experimen...

We evaluated the effectiveness of metallic shields that were used for reduction of the breast dose in thoracic computed tomography(CT). For the evaluation, we measured breast surface dose and image standard deviation(SD)in the lung area. The metallic shields were made from bismuth, zinc, copper, and iron. The bismuth shield has been marketed and used for dose reduction. The other three metallic...

I For a description of the phenomena of magnetic resonance see W. Gordy, W. V. Smith, and R. F. Trambarulo, Microwave Spectroscopy (New York: John Wiley & Sons, Inc., 1953), chap. v. See also chap. ii. by W. Gordy, of Chemical Applications of Spectroscopy, soon to be published by Interscience Publishers, Inc., in the "Techniques of Organic Chemistry" series, ed. A. Weissberger. 2 B. Commoner, J...