magnet-, magneto- +
(Greek: Magnesian [stone]; Magnesia having been a mineral-rich region of Thessaly)
2. The effect of an external magnetic field on living organisms.
2. A reference to a class of substances; such as, bismuth and copper, whose permeability is less than that of a vacuum.
In a magnetic field, their induced magnetism is in a direction opposite to that of iron.
A disrupted flow of water indicates where there could be an underlying abnormality in the brain.2. A new type of magnetic resonance technology which has, among other things, for the first time shown "white matter" in action, revealing its role in the brain.
Although gray matter (composed of neurons) does the brain's thinking and calculating, white matter (composed of myelin-coated axons, or long fibers of nerve cells), control the signals which neurons share, co-ordinating how well brain regions work together.
Diffusion tensor imaging (DTI) is done with the same kind of magnetic resonance imaging (MRI) machines found in hospitals; however, it involves a different type of magnetic field and different algorithms to create the many brain-image slices that are assembled into a three-dimensional picture.
DWI, or diffusion weighted imaging, has been demonstrated to be more sensitive for the early detection of stroke than standard pulse sequences and is closely related to temperature mapping.
2. A magnet consisting of a core, often made of soft iron, that is temporarily magnetized by an electric current flowing through a coil that surrounds it.
3. A coil of wire usually wound on a soft iron or steel core.
When current is passed through the coil a magnetic field is generated and the core provides an easy path for the magnetic lines of force. This concentrates the electric field in the core.
2. Involving or relating the interaction of electric and magnetic fields, both static and dynamic.
3. A reference to magnetism that is induced by an electric current.
4. Pertaining to radiation; such as, light, microwaves, X-rays, gamma rays, or radio waves.
5. Referring to the combined electric and magnetic fields associated with radiation or movements of electrons or other charged particles through conductors or space.
2. With the property of ferromagnetism.
Iron, cobalt, and nickel are ferromagnetic metals.
2. The property of certain metals and alloys; especially, those of the iron group, rare-earth, and acitinide series, that are capable of spontaneous magnetic polarization, resulting in drastic magnetic effects.
These materials are strongly attracted to magnets and are used in permanent magnets and various ceramic compounds.
2. Having properties, or characteristics, of geomagnetism.
The study of the sources, configurations, and changes in the earth's magnetic field and the study and interpretation of the remaining magnetism in rocks as a result of the earth's magnetic field when the rocks were formed which is known as paleomagnetism.
The intensity of the magnetic field at the earth's surface is approximately 0.32 gauss at the equator and 0.62 gauss at the north pole.
A gauss equivalent to 1 maxwell per square centimeter and a maxwell is equivalent to the flux that produces one abvolt in a one-turn circuit when the flux is reduced to zero at a uniform rate in one second; while a flux is the electric or magnetic field lines of force that traverse a given cross-sectional area.