Harold Elford Johns (4 July 1915 – 23 August 1998) was a Canadian medical physicist, noted for his extensive contributions to the use of ionizing radiation to treat cancer. Events 836 - Pactum Sicardi, peace between the Principality of Benevento and the Duchy of Naples Year 1915 ( MCMXV) was a Common year starting on Friday (link will display the full calendar of the Gregorian calendar (or a Common year Events 79 - Mount Vesuvius begins stirring on the feast day of Vulcan the Roman god of fire Year 1998 ( MCMXCVIII) was a Common year starting on Thursday (link will display full 1998 Gregorian calendar) Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page Medical physics is the application of Physics to Medicine. It generally concerns physics as applied to Medical imaging and Radiotherapy, although Image talkNew_radiation_symbol_ISO_21482svg for details --> Ionizing radiation Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled
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Early life and education
Johns was born to missionary parents in Szechuan, China. ( Postal map spelling: Szechwan and Szechuan) is a province in western China with its capital in Chengdu. He lived in China until 1926, when political unrest prompted his parents to return to North America. Year 1926 ( MCMXXVI) was a Common year starting on Friday (link will display the full calendar of the Gregorian calendar. After spending time in Tacoma, Washington and Brandon, Manitoba, his family settled in Hamilton, Ontario. Brandon is a City in southwestern Manitoba, Canada. The surrounding area is often referred to as " Westman " Hamilton (ˈhæməltən ( 2006 population 504559 UA population 647634 CMA population
In Hamilton, Johns pursued a degree in mathematics in physics at McMaster University and completed his B. McMaster redirects here for others see McMaster (disambiguation. Sc. in 1936. Year 1936 ( MCMXXXVI) was a Leap year starting on Wednesday (link will display the full calendar of the Gregorian calendar. He then moved to the University of Toronto, where he earned an M. This article is about the University of Toronto's St George Campus A. and Ph. D. in physics in 1939. Year 1939 ( MCMXXXIX) was a Common year starting on Sunday (link will display the full calendar of the Gregorian calendar.
Early career
Johns' graduation coincided with the start of World War II. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including For the duration of the war, he taught physics, mathematics, radar, and radio navigation to newly recruited pilots as part of the British Commonwealth Air Training Plan. The British Commonwealth Air Training Plan, also known as the Empire Air Training Scheme, Empire Air Training Plan, Commonwealth Air Training Plan Based on his radiography and physics experience, Johns was also involved in noninvasive x-ray testing of metal aircraft castings.
He married his wife, Sybil Hawkins, in 1940. Their marriage lasted until Johns' death fifty-eight years later.
Cobalt bomb
After the close of the war, Johns was invited to work with Ertle Harrington at the University of Saskatchewan. The University of Saskatchewan ( U of S) is a Coeducational public Research university located on the east side of the South Saskatchewan It was there in Saskatoon that he conducted his pioneering research in the use of cobalt-60 as a gamma ray source for the radiation treatment of cancer. Saskatoon is a city located in central Saskatchewan, Canada, on the South Saskatchewan River, with a Cobalt (ˈkoʊbɒlt is a hard lustrous silver-grey Metal, a Chemical element with symbol Co. Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions Radiation therapy (or radiotherapy) is the medical use of Ionizing radiation as part of Cancer treatment to control Malignant Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled
Interest in nuclear technology exploded in postwar Canada. Nuclear research facilities constructed at Chalk River, Ontario near the end of the war were expanded and opened to civilian research projects. The Chalk River Laboratories (also known as CRL, Chalk River Labs and formerly the Chalk River Nuclear Laboratories, CRNL) is a Canadian The first operational nuclear reactor outside the United States–NRX–was located at Chalk River, and it provided a source of activated cobalt-60 for Johns' experiments. NRX was a Heavy water moderated, light water cooled nuclear research reactor at the Canadian Chalk River Laboratories, which came
Two groups–Johns' at the University of Saskatchewan, and another in London, Ontario–designed and constructed external beam radiotherapy instruments using cobalt sources. London is a city in Southwestern Ontario, Canada along the Quebec City-Windsor Corridor with a metropolitan area population of 457720 the city proper External beam radiotherapy otherwise known as teletherapy, is the most frequently used form of Radiotherapy. Ultimately, the first treatment was delivered in London, on 27 October 1951. Events 312 - Constantine the Great is said to have received his famous Vision of the Cross. Year 1951 ( MCMLI) was a Common year starting on Monday. Events of 1951 January
In early 1952, Maclean's magazine had dubbed the cobalt-source radiotherapy machine the cobalt bomb—a tongue-in-cheek tribute to this peaceful use of nuclear technology. Year 1952 ( MCMLII) was a Leap year starting on Tuesday (link will display full calendar of the Gregorian calendar. Maclean's is a Canadian weekly News magazine, reporting on Canadian issues such as politics pop culture and current events
Johns' original device was used in Saskatchewan until 1972. Year 1972 ( MCMLXXII) was a Leap year starting on Saturday (link will display full calendar of the Gregorian calendar.
Ontario Cancer Institute
In 1956, Johns assumed the headship of the physics division of the Ontario Cancer Institute at Princess Margaret Hospital in Toronto. Year 1956 ( MCMLVI) was a Leap year starting on Sunday (link will display full calendar of the Gregorian calendar. Princess Margaret Hospital is located in downtown Toronto Ontario Canada on University Avenue at College Street
To further scientific and medical collaborations between radiologists, radiotherapists, physicians, and physicists, Johns guided the creation of the Graduate Department in Medical Biophysics at the University of Toronto in 1958. Year 1958 ( MCMLVIII) was a Common year starting on Wednesday (link will display full calendar of the Gregorian calendar. Johns served as the second Chair of the Department, succeeding Arthur Ham in 1960. Arthur Worth Ham ( 20 February 1902 &ndash 6 September 1992) was a prominent Canadian histologist. Year 1960 ( MCMLX) was a Leap year starting on Friday (link will display full calendar of the Gregorian calendar.
Over the course of his career, Johns supervised sixty-eight graduate students and published more than two hundred peer-reviewed papers.
Awards
- Officer of the Order of Canada (1978)
- Emeritus University Professor of the University of Toronto
- Canadian Medical Hall of Fame inductee (1998)
Further reading
- Greenstock, Clive L. The Order of Canada is the highest civilian honour within the Canadian system of honours, with membership awarded to those who exemplify the order's Latin This article is about the University of Toronto's St George Campus The Canadian Medical Hall of Fame is a Canadian charitable organization founded in 1994 that honours Canadians who have contributed to the understanding of disease and improving A New Kind of Ray: The Radiological Sciences in Canada 1895-1995. eds. J. A. Aldrich and B. C. Lentle, The Canadian Association of Radiologists, Montreal 1995.
- Johns, Harold E. and Cunningham, John R. The Physics of Radiology, 4th Edition, Charles C Thomas, Springfield 1983.
- Johns, H. E. , Bates L. M. , Epp E. R. , et al. 1,000-curie cobalt 60 units for radiation therapy. Nature. 168(4285):1035-6, 1951.
External links
- Biographical sketch from the Canadian Nuclear Society
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