Summary. 1  Algae are a necessary component of any healthy natural pond ecosystem. 2  However, excessive inputs of nutrients can lead to an overabundance of algae. 3  Excessive growth of filamentous algae, referred to as mats, moss, or scum, is one of the most common problems encountered by pond owners.
From Wikipedia, the free encyclopedia. The history of radiation therapy or radiotherapy can be traced back to experiments made soon after the discovery of x-rays (1895), when it was shown that exposure to radiation produced cutaneous burns.ases sprung up of the development of carcinoma in patients who had used conventional radium therapy up to 40 years after the original treatments. Robley D. Evans made the first measurements of exhaled radon and radium excretion from a former dial painter in 1933.
Most radiation therapy is administered by a radiation oncologist at a radiation center and usually begins three to four weeks after surgery. The radiation is used to destroy undetectable cancer cells and reduce the risk of cancer recurring in the affected breast.There are two main kinds of radiation therapy that may be considered, and some people have both.he radiation is used to destroy undetectable cancer cells and reduce the risk of cancer recurring in the affected breast. There are two main kinds of radiation therapy that may be considered, and some people have both.