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--- analytic_z-spectra-cw-2pool [2016/02/14 00:05]
+++ analytic_z-spectra-cw-2pool [2021/10/11 13:22] (current)
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+====== Analytic Z-spectra  water, CEST - cw ======
+Here you find analytic solutions of the Bloch-McConnell equations describing Z-spectra.
+This is the R<sub>1ρ</sub>-model as published in **Zaiss and Bachert (2013), NMR Biomed., 26: 507–518. [[http://onlinelibrary.wiley.com/doi/10.1002/nbm.2887/abstract|doi: 10.1002/nbm.2887]]**. {{ :z_cw_b1.png?nolink&300|}}
+It is a very lean code to give you a tool illustrating the principal behaviour of a CEST effect and its interaction with the direct water saturation.
+Dowload zipped Matlab implementations [[https://github.com/cest-sources/Z-cw/archive/master.zip|here]] or find the package on [[https://github.com/cest-sources/Z-cw|github.com/cest-sources/Z-cw]]
+======  Tutorial ======
+{{youtube>bSv7H7lUnTg?640x480|Tutorial: 2 minutes for 2 pools}}
+===== The code ======
+=== BATCH_Z_cw ===
+First the pool parameters are defined in the parameter struct P:
+<code matlab>
+%% SETUP
+%pool system parameters
+%water pool A
+P.R1A=1/3;          % longitudinalrelaxation rate [s^-1]
+P.R2A=2;            % transversal relaxation rate [s^-1]
+P.dwA=0;            %deltaW_A in [ppm]
+%CEST pool B
+P.fB=0.001;         % proton fraction: [water protons]/[CEST agent protons]
+P.kBA=200;          % exchange rate [s^-1]
+P.dwB=1.9;          % (chemical shift) deltaW_B in [ppm}
+P.R2B=30;           % transversal relaxation rate [s^-1]
+</code>
+Now the CEST sequence parameters are defined
+<code matlab>
+% sequence parameters
+P.Zi=1;             % Z initial, in units of thermal M0, Hyperpol.: 10^4
+P.FREQ=300;         % [MHz]  I use ppm and µT, therefore gamma=267.5153;
+P.B1=2;             % [µT]
+P.tp=5;             % pulse duration = saturation time [s]
+P.xZspec= [-5:0.1:5]; % ppm
+</code>
+Now the function Z_cw(P) is called and plotted:
+<code matlab>
+figure(32), plot(P.xZspec,Z_cw(P),'r-') ;   hold on;
+</code>
+=== function Z_cw(P) ===
+{{ :logo_dkfz.png?direct&180|powered by DKFZ}}

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