Plasma medicine Plasma medicine Plasma medicine is an emerging field that combines plasma physics, life sciences and clinical medicine. It is being studied in disinfection, healing, and cancer. Most of the research is in vitro and in animal models. It uses ionized gas (physical plasma) for medical uses or dental applications . Plasma, often called the fourth state of matter, is an ionized gas containing positive ions and negative ions or electrons, but is approximately charge neutral on the whole. The plasma sources used for plasma medicine are generally low temperature plasmas, and they generate ions, chemically reactive atoms and molecules, and
Positive element Positive element In mathematics, especially functional analysis, a self-adjoint (or Hermitian) element formula_1 of a C*-algebra formula_2 is called positive if its spectrum formula_3 consists of non-negative real numbers. Moreover, an element formula_1 of a C*-algebra formula_2 is positive if and only if there is some formula_6 in formula_2 such that formula_8. A positive element is self-adjoint and thus normal. If formula_9 is a bounded linear operator on a complex Hilbert space formula_10, then this notion coincides with the condition that formula_11 is non-negative for every vector formula_12 in formula_10. Note that formula_11 is real for every formula_12 in formula_10