Other

Strawberries protect the stomach from alcohol

In an experiment on rats, European researchers have proved that eating strawberries reduces the harm that alcohol can cause to the stomach mucous membrane. Published in the open access journal Plos One, the study may contribute ...

Alzheimer's disease & dementia

Discovery prompts rethink on metals and Alzheimer's disease

Researchers at the University of Melbourne have discovered that a protein involved in the progression of Alzheimer's disease also has properties that could be helpful for human health.

Cardiology

Novel antioxidant makes old blood vessels seem young again

Older adults who take a novel antioxidant that specifically targets cellular powerhouses, or mitochondria, see age-related vascular changes reverse by the equivalent of 15 to 20 years within six weeks, according to new University ...

Medical research

Mitochondria trigger cell aging, study shows

An international team of scientists has for the first time shown that mitochondria, the batteries of the cells, are essential for ageing.

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Radical (chemistry)

In chemistry, radicals (often referred to as free radicals) are atoms, molecules, or ions with unpaired electrons on an otherwise open shell configuration. These unpaired electrons are usually highly reactive, so radicals are likely to take part in chemical reactions. Radicals play an important role in combustion, atmospheric chemistry, polymerization, plasma chemistry, biochemistry, and many other chemical processes, including human physiology. For example, superoxide and nitric oxide regulate many biological processes, such as controlling vascular tone. "Radical" and "free radical" are frequently used interchangeably, although a radical may be trapped within a solvent cage or be otherwise bound. The first organic free radical identified was triphenylmethyl radical, by Moses Gomberg in 1900 at the University of Michigan.

Historically, the term radical has also been used for bound parts of the molecule, especially when they remain unchanged in reactions. These are now called functional groups. For example, methyl alcohol was described as consisting of a methyl "radical" and a hydroxyl "radical". Neither are radicals in the modern chemical sense, as they are permanently bound to each other, and have no unpaired, reactive electrons. They can, however, be observed as radicals in mass spectrometry after breaking down the substance with a hail of energetic electrons.

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