Noninvasive measurements

For these reasons the Cooperative Hypothesis seems to be a plausible alternative to the Latch Bridge Hypothesis. Given that computer calculations of the behavior of various hypothetical schemes are now possible, an independent, noninvasive measure of distribution of myosin among the states would be of great use for further understanding of crossbridge kinetics. 

In recent studies on perfused rats hearts (Veitch et al., 1992), it was found that differences in the sensitivity of complexes 1-lV to ischaemic damage were dependent upon the duration of ischaemia and the presence of oxygen. The demonstration that complex 1 is a major defective site dependent upon isolation of mitochondria from homogenates of the tissue by in vitro methods seemed important to us. We therefore decided to attempt to make noninvasive measurements of mitochondrial function soon after reperfusion in transplanted rabbit kidneys by surface fluorescence (for mitochondrial NADH levels) and near infra-red spectroscopy (NIRS) for the redox state of cytaas. 

Ermakov IV et al. (2005), Two-wavelength Raman detector for noninvasive measurements of carotenes and lycopene in human skin, SPIE Proc., 5686, 131-141. 

The above-mentioned early supplementation studies with xanthophylls did not measure the changes in MPOD associated with supplementation probably because an easy-to-use technique for its noninvasive measurement in the human retina eye was not available at that time. The first apparatus for this purpose had been described in 1953 by deVries et al. (1953) and it is only since the 1970s that publications can be found that report on systematic measurements of MPOD in the human retina. 

The direct experimental verification of the computed flow field requires noninvasive measurements of velocity components inside the packed tube. One very promising technique for this is magnetic resonance (MR) as described in a recent review by Gladden (2003). She showed pictures of 3D MR visualization of axial velocity for flow of water in packings of spheres, and her group has used MR to connect the 3D structure of a packed bed to the transport phenomena in... 

The validation of CFD codes by comparison to reliable experiments is of the highest importance. Especially promising is the use of MRI methods to non-invasively provide flow fields and dispersion data. Major challenges will be to extend MRI and similar methods such as LDV and particle tracking to a wider range of conditions, and to develop noninvasive measurements of temperature to improve verification of heat transfer simulations. 

M. A. Franceschini and D. A. Boas. Noninvasive measurement of neuronal activity with near-infrared optical imaging. Neuroimage, 21 372-386, 2004. 

To detect dynamic featnres of colloidal preparations, additional methods are required. Nuclear magnetic resonance spectroscopy allows a rapid, repeatable, and noninvasive measurement of the physical parameters of lipid matrices withont sample preparation (e.g., dilution of the probe) [26,27]. Decreased lipid mobility resnlts in a remarkable broadening of the signals of lipid protons, which allows the differentiation of SLN and supercooled melts. Because of the different chemical shifts, it is possible to attribute the nuclear magnetic resonance signal to particnlar molecnles or their segments. 

Y.L. Chung, H. Troy, I.R. Judson, R. Leek, M.O. Leach, M. Stubbs, A.L. Harris, J.R. Griffiths, Noninvasive measurements of capecitabine metabolism in bladder tumors overexpressing thymidine phosphorylase by fluorine-19 magnetic resonance spectroscopy, Clin. Cancer Res. 10 (2004) 3863-3870. 

The best conclusion that can be drawn from these data is perhaps that treatment with naltrexone may offer promise for some, but certainly not all, patients with self-injury. Treatment effects may depend on background opioid levels, dosage, and treatment regimen. Noninvasive measures that predict individual treatment response have not been established. Self-injury is a heterogeneous phenomenon from a clinical and biological perspective (Buitelaar, 1993 Willemsen-Swinkels et ah, 1998). Further studies are required in this area, and and should include carefully clinically documented cases, large samples, and controlled designs. At this time, the use of naltrexone for the treatment of self-injury is to be considered experimental. 

The new protocols presented here deal with the direct evaluation of antioxidant global capacity applied to skin and dermo-cosmetic creams. The analyses are performed directly in the medium without pre-treatment of the samples. This allows a simple and noninvasive measurement without introducing any possible interference. Moreover, cyclic voltammetry provides results in quasi-real time, allowing the direct monitoring of reaction kinetics. 

Finally, the robustness of the calibration is a critical parameter that must be established before any noninvasive measurement technology will be useful. Important issues include (1) the ability to collect reliable spectra for each measurement (2) a protocol required to establish a working calibration model (3) time stability of a calibration model and (4) sensitivity of the calibration model to external factors, such as ambient temperature and vibrations. These issues go far beyond demonstrating the feasibility of a noninvasive spectroscopic sensor but pertain to its eventual practical implementation. 

Maruo K, Tsurugi M, Tamura M, Ozaki Y. In vivo noninvasive measurement of blood glucose by near-infrared diffuse-reflectance spectroscopy. Applied Spectroscopy 2003,57, 1236-1244. 

Bruulsema JT, Hayward JE, Farrell TJ, Patterson MS, Heinemann L, Berger M, Koschinsky T, Sandahl-Christiansen J, Orskov H. Correlation between blood glucose concentration in diabetics and noninvasively measured tissue optical scattering coefficient. Optics Letters 1997, 22, 190-192. 

Figure 13.11 PLS calibration model results for the noninvasive measurement of glucose in rat skin indicating spectra used for training (squares) and validation (circles) of the model.

Weersink R, Patterson MS, Diamond K, Silver S, Padgett N. Noninvasive measurement of fluorophore concentration in turbid media with a simple fluorescence/reflectance ratio technique. Applied Optics 2001, 40, 6389-6395. 

Hamelmann, E., Schwarze, J., Takeda, K., Oshiba, A., Larsen, G. L., Irvin, C. G and Gelfand, E. W. (1997) Noninvasive measurement of airway responsiveness in allergic mice using barometric plethysmography. Am. J. Respir. Crit. Care Med. 156, 766-775. 

Experimental validation of CFD results is considered a prerequisite to paving the road for widespread acceptance of CFD in the chemical engineering community, especially in connection with multiphase flow applications. The authors do not intend to give here a complete review on available measuring techniques for single-phase and multiphase flows only the more advanced techniques are briefly discussed. For an overview of the latest advances realized in noninvasive measurement of multiphase systems the interested reader is referred to Chaouki et al (1997). The available experimental techniques can be classified according to the following aspects ... 

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