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Result : Searchterm 'Magnetization Vector' found in 3 terms [] and 17 definitions []
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Magnetization Vector
 
The integration of all the individual nuclear magnetic moments, which have a positive magnetization value at equilibrium versus those in a random state.
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Net Magnetization Vector
 
Hydrogen nuclei magnetic moments are randomly oriented in the absence of an external magnetic field and are considered to have a net magnetization of zero. Once hydrogen protons are placed in the presence of an external magnetic field, they align themselves in one of two directions, parallel or anti parallel to the net magnetic field, which is commonly referred to as the vector B0. The parallel and anti parallel protons cancel each other out, only the small number of low energy protons left aligned with the magnetic field create the overall net magnetization, this difference is all that counts. The magnetic moments of these protons are added together and are referred to as net magnetization vector (NMV) or the symbol 'M'.

See also Magnetization Transfer Contrast.
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Further Reading:
  Basics:
Mapping of low flip angles in magnetic resonance(.pdf)
Saturday, 1 January 2011   by www.hal.inserm.fr    
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Macroscopic Magnetization Vector
 
Net magnetic moment per unit volume (a vector quantity) of a sample in a given region, considered as the integrated effect of all the individual microscopic nuclear magnetic moments.
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Phase Encoding
 
The process of locating a MR signal by altering the phase of spins in one dimension with a pulsed magnetic field gradient along that dimension prior to the acquisition of the signal.
If a gradient field is briefly switched on and then off again at the beginning of the pulse sequence right after the radio frequency pulse, the magnetization of the external voxels will either precess faster or slower relative to those of the central voxels.
During readout of the signal, the phase of the xy-magnetization vector in different columns will thus systematically differ. When the x- or y- component of the signal is plotted as a function of the phase encoding step number n and thus of time n TR, it varies sinusoidally, fast at the left and right edges and slow at the center of the image. Voxels at the image edges along the phase encoding direction are thus characterized by a higher 'frequency' of rotation of their magnetization vectors than those towards the center.
As each signal component has experienced a different phase encoding gradient pulse, its exact spatial reconstruction can be specifically and precisely located by the Fourier transformation analysis. Spatial resolution is directly related to the number of phase encoding levels (gradients) used. The phase encoding direction can be chosen, e.g. whenever oblique MR images are acquired or when exchanging frequency and phase encoding directions to control wrap around artifacts.
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Further Reading:
  Basics:
Magnetic resonance imaging
   by www.scholarpedia.org    
Aliasing or wrap around artifacts
Thursday, 31 March 2011   by de.slideshare.net    
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Adiabatic Fast Passage
 
(AFP) Adiabatic fast passage is a NMR technique of producing rotation of the macroscopic magnetization vector by shifting the frequency of RF energy pulses (or the strength of the magnetic field) through resonance (the Larmor frequency) in a time short compared to the relaxation times. Particularly used for inversion of the spins between high and low energy states with an excess of spins in the higher energy level. A continuous wave NMR technique used in e.g., MR spectroscopy.
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Further Reading:
  Basics:
Adiabatic theorem
   by en.wikipedia.org    
  News & More:
New theory of adiabaticity developed
Tuesday, 2 December 2008   by www.upi.com    
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