density


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density

 [den´sĭ-te]
1. the ratio of the mass of a substance to its volume.
2. the quality of being compact.
3. the quantity of matter in a given space.
4. the quantity of electricity in a given area, volume, or time.
5. the degree of film blackening in an area of a photograph or radiograph.

den·si·ty (ρ),

(den'si-tē),
1. The compactness of a substance; the ratio of mass to unit volume, usually expressed as g/cm3 (kg/m3 in the SI).
2. The quantity of electricity on a given surface or in a given time per unit of volume.
3. radiologic physics the opacity to light of an exposed radiographic or photographic film; the darker the film, the greater will be the measured density.
4. clinical radiology a less exposed area on a film, corresponding to a region of greater x-ray attenuation (radiopacity) in the subject; the more light transmitted by the film, the greater the density of the subject will be; this is not actually the opposite of sense 3, because one concerns film density and the other subject density.
[L. densitas, fr. densus, thick]

density

The amount of a substance per unit volume Imaging
1. The compactness in a scan which reflects the type of tissues seen in CT and MR scans.
2. The amount of 'hard' or mineralized tissue in a plain film. See Bone mineral, Current density, Muscle fiber density, Spin density, Vapor density.

den·si·ty

, pl. densities (dens'i-tē, -tēz)
1. The compactness of a substance; the ratio of mass to unit volume, usually expressed as g:cm3 (kg:m3 in SI).
2. The quantity of electricity on a given surface or in a given time per unit of volume.
3. radiologic physics The opacity to light of an exposed radiographic or photographic film; the darker the film, the greater the measured density.
4. clinical radiology A less-exposed area on a film, corresponding to a region of greater x-ray attenuation (radiopacity) in the subject; the more light transmitted by the film, the greater the density of the subject; this is not actually the opposite of the sense 3 definition, because one concerns film density and the other subject density.
[L. densitas, fr. densus, thick]

density

An indication of the compactness of a substance. It is expressed as the ratio of the mass of the substance to its unit volume. The common units are g/cm3 and kg/m3. This property is usually given by lens manufacturers, the greater the density of a material, the greater its weight, all other factors being equal.

den·si·ty

, pl. densities (dens'i-tē, -tēz)
1. Compactness of a substance.
2. Quantity of electricity on a given surface or in a given time per unit of volume.
3. radiologic physics opacity to light of an exposed radiographic or photographic film; the darker the film, the greater the measured density.
4. clinical radiology a less exposed area on a film, corresponding to a region of greater x-ray attenuation (radiopacity) in the subject.
[L. densitas, fr. densus, thick]

Patient discussion about density

Q. what are the sources for high density lipoprotein? I have heard that high density lipoprotein is good for heart. What differences does it make in heart’s health and what are the sources for high density lipoprotein?

A. Hi Liam, it is very important that we have high density lipoprotein (HDL) in our body. The fact is that the HDL is formed inside the body. They are known as good cholesterol as they are famous for their protection for heart against the heart diseases. It has been found that Vitamin B3 or Niacin consumption increases the count of HDL. It’s good to cut on the diet having more of saturated fats and oils, which increases the chances of heart attack.

More discussions about density
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The research team used accepted statistical methods to single out factors linked to lower bone mineral density. This type of analysis simultaneously considers the impact of several factors that may affect bone density.
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We examined the differences between the three abovementioned categories of bears in 1) distance to sites where bears were fed, 2) the human density in the given municipality and 3) the density of the bear observations recorded as sights or signs/[km.sup.2] land area within 50 X 50 km squares.
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