Search results
Results from the WOW.Com Content Network
Leonard Dawe, Telegraph crossword compiler, created these puzzles at his home in Leatherhead. Dawe was headmaster of Strand School, which had been evacuated to Effingham, Surrey. Adjacent to the school was a large camp of US and Canadian troops preparing for D-Day, and as security around the camp was lax, there was unrestricted contact between ...
Fundamental to radiation protection is the avoidance or reduction of dose using the simple protective measures of time, distance and shielding. The duration of exposure should be limited to that necessary, the distance from the source of radiation should be maximised, and the source or the target shielded wherever possible.
Lead shielding refers to the use of lead as a form of radiation protection to shield people or objects from radiation so as to reduce the effective dose. Lead can effectively attenuate certain kinds of radiation because of its high density and high atomic number ; principally, it is effective at stopping gamma rays and x-rays .
The abbreviation is not always a short form of the word used in the clue. For example: "Knight" for N (the symbol used in chess notation) Taking this one stage further, the clue word can hint at the word or words to be abbreviated rather than giving the word itself. For example: "About" for C or CA (for "circa"), or RE.
The edges of the drapes are secured with adhesive tape or other means to prevent the drapes from moving during the procedure. The use of surgical drape not only serves to protect the surgical site, but also expands the sterile field, allowing surgical team members to place sterile supplies onto them.
The International Commission on Radiological Protection (ICRP) describes how deterministic effects, or harmful tissue reactions, occur. [5] There is a threshold dose which causes clinical radiation damage of cells in the body. [5] As the dose increases, the severity of injury increases. [5] This also impairs tissue recovery. [5]
Thus, a copper X-ray source with a nickel filter can produce a nearly monochromatic X-ray beam with photons of mostly 154 pm. For medical purposes, X-ray filters are used to selectively attenuate, or block out, low-energy rays during x-ray imaging (radiography). Low energy x-rays (less than 30 keV) contribute little to the resultant image as ...
William Herbert Rollins (June 19, 1852 - 1929) was an American scientist, inventor, and dentist. He was a pioneer in radiation protection.Many of his inventions and investigations in medical radiography and photography have been ranked in importance with those of Thomas A. Edison, Elihu Thomson, and William J. Morton.