Around mid-century, Mendeleev began to develop the table of elements which helped in the discovery of new elements. In the last decade of the century, the discovery of radium by Marie and Pierre Curie, and the electron by Becquerel as well as observation of radioactivity in the laboratory, challenged Dalton's theory.
Medications Used to Treat ADHD. Stimulant medications commonly prescribed for attention deficit disorder include methylphenidate (Ritalin, Concerta, Metadate, Methylin) and certain amphetamines (Dexedrine, Dextrostat, Adderall). Methylphenidate is a short acting drug, and in older forms, had to be taken multiple times a day.
This medicine will help to reduce the symptoms of hyperactivity and impulsive behaviour. It will also help to increase attention and concentration span. Methylphenidate is used as part of a comprehensive treatment programme for ADHD. Tablets: 5 mg, 10 mg, 20 mg; these contain small amounts of lactose.