Plasma deconvolution techniques

When plasma deconvolution techniques are applied, the isotopic label should be infused slowly and doses for the intravenous label should be kept as low as possible in order not to disturb element homeostasis. Plasma deconvolution is rather invasive and more labor-intensive as it involves the analysis of a dozen or more plasma samples per subject, as opposed to a single sample in most other... 

To circumvent these difficulties, researchers have developed deconvolution techniques that make no assumption regarding the order of the absorption process. With the use of deconvolution techniques, it is possible to separate the absorption process from disposition, allowing for the expression of absorption as % unabsorbed vs. time or % absorbed vs. time. Analysis of these plots permits an evaluation of the absorption process with fewer assumptions"than an analysis of the plasma concentration-time curve using the method of residuals. A lag time, first-order or parallel first-order processes (i.e., absorption and metabolism) and a zero-order absorption can sometimes be unambiguously determined from % unabsorbed vs. time plots (Figure 1.4). A minimum of five plasma concentrations measured in the absorption phase is usually necessary to reliably determine by deconvolution methods. 

The delta-function deconvolution method (FFT) was used to improve the spectral resolution and to remove the plural scattering effect at the core-loss edge in electron energy-loss spectroscopy (EELS). The zero-loss peak (used as an instrumental resolution function) works as a nonattenuation high-pass filter in this technique [17]. Reflectance spectra in the vacuum ultraviolet of microcrystalline 3-BN, prepared by plasma CVD (chemical vapor deposition), and of sintered (3-BN measured with synchrotron radiation in the energy range from 5 to 25 eV, show reflectance peaks near 11.4 and 14 eV and a broad peak near 18 eV. The peaks at 11.4 and 14.0 eV are assigned to the E and E2 peaks of the sphalerite-type semiconductor [18]. 

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