The glucose level that defines hypoglycemia is variable. In people with diabetes levels below 3.9 mmol/L (70 mg/dL) is diagnostic. In adults without diabetes, symptoms related to low blood sugar, low blood sugar at the time of symptoms, and improvement when blood sugar is restored to normal confirm the diagnosis.he precise level of glucose considered low enough to define hypoglycemia is dependent on (1) the measurement method, (2) the age of the person, (3) presence or absence of effects, and (4) the purpose of the definition.
Medical Definition of EMISSIVITY. : the relative power of a surface to emit heat by radiation: the ratio of the radiant energy emitted by a surface to that emitted by a blackbody at the same temperature.
Real materials emit energy at a fractionâcalled the emissivity âof black-body energy levels. By definition, a black body in thermal equilibrium has an emissivity of Îµ = 1.0. A source with lower emissivity independent of frequency often is referred to as a gray body.Construction of black bodies with emissivity as close to one as possible remains a topic of current interest.y definition, a black body in thermal equilibrium has an emissivity of Îµ = 1.0. A source with lower emissivity independent of frequency often is referred to as a gray body. Construction of black bodies with emissivity as close to one as possible remains a topic of current interest.