A simple and speedy device to measure the acidity and alkalinity of a fluid. A pH meter acts as a volt meter that measures the electrical potential difference between a pH electrode and a reference electrode and displays the result in terms of the pH value of the solution in which they are immersed.
The pH meter was invented in 1934 by the American chemist Arnold O. Beckman (1900-2004) to measure the sourness of lemons. Beckman’s original device was housed in a walnut box 12 inches wide, 8 inches deep and 9 inches high. It measured electrical current flowing into a glass electrode immersed in a solution. The amount of current indicated the solution’s acidity.
Doctor of Philosophy. (From the New Latin, philosophize doctor). Ph.D.’s are involved in clinical care (as in clinical psychology), biomedical research, health administration and other areas in medicine.
A type of cataract surgery in which the lens with the cataract is broken up by ultrasound, irrigated, and suctioned out.
Short for bacteriophage, a virus that lives within a bacteria. A virus for which the natural host is a bacterial cell. Bacteriophages have been very important and heuristic in bacterial and molecular genetics. Phages were studied by (among others) Alfred Hershey, Max Delbruck and Salvador Luria who discovered that viruses could exchange genetic material. Hershey […]
- Phagedenic gingivitis
This is trench mouth, a progressive painful infection with ulceration, swelling and sloughing off of dead tissue from the gums due to infection. Certain germs (including fusiform bacteria and spirochetes) have been thought to be involved, but the full story behind this long- known disease is still not clear. This condition is also called Vincent’s […]
phagocyte, a cell that can engulf particles; and phagophobia, an excessive fear of eating.