History of malaria millennium BCE in Greece and China. For thousands of years, traditional herbal remedies have been used to treat malaria. The first effective treatment for malaria came from the bark of cinchona tree, which contains quinine. After the link to mosquitos and their parasites were identified in the early twentieth century, mosquito control measures such as widespread use of the insecticide DDT, swamp drainage, covering or oiling the surface of open water sources, indoor residual spraying and use of insecticide treated nets was initiated. Prophylactic quinine was prescribed in malaria endemic areas, and new therapeutic drugs, including chloroquine and artemisinins, were
Hard water the effects of hard water on the surfactants. For this reason, water softening is often unnecessary. Where softening is practised, it is often recommended to soften only the water sent to domestic hot water systems so as to prevent or delay inefficiencies and damage due to scale formation in water heaters. A common method for water softening involves the use of ion exchange resins, which replace ions like Ca by twice the number of monocations such as sodium or potassium ions. Washing soda (sodium carbonate - NaCO) is easily obtained and has long been used as a water softener for