Oncology & Cancer

Inhibition of p38 reduces the growth of lung tumors

One of the biggest challenges faced by biomedicine is the development of more selective and efficient cancer treatments. In 2018, 1.7 million people died from lung cancer worldwide, a number equivalent to the population of ...

Neuroscience

New tool for investigating brain cells, Parkinson's, and more

NMDARs (N-methyl-D-aspartate receptors) serve as valves on nerve cells, controlling the flow of electrical signals in the brain. This special group of receptors is suspect in many neurological diseases, including Alzheimer's, ...

Health

Pot while pregnant: medicine doctors urge caution

Daily marijuana use during pregnancy may lead to an increased risk of low birth weight, low resistance to infection, decreased oxygen levels and other negative fetal health outcomes, according to a new study from a team of ...

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Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions and that have a unique and defined chemical structure. Chemical compounds consist of a fixed ratio of atoms that are held together in a defined spatial arrangement by chemical bonds. Chemical compounds can be compound molecules held together by covalent bonds, salts held together by ionic bonds, metallic compounds held together by metallic bonds, or complexes held together by coordinate covalent bonds. Substances such as pure chemical elements and elemental molecules consisting of multiple atoms of a single element (such as H2, S8, etc.) are not considered chemical compounds.

Elements form compounds to become more stable. They become stable when they have the maximum number of possible electrons in their outermost energy level, which is normally two or eight valence electrons. This is the reason that noble gases do not frequently react: they already possess eight valence electrons (the exception being helium, which requires only two valence electrons to achieve stability).

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