Indicator diffusion method

C. Crone. The permeability of capillaries in various organs as determined by use of the indicator diffusion method. Acta Physiol. Scand., 58 292-305, 1963. 

Spherical vaterite crystals were obtained with 4-mercaptobenzoic acid protected gold nanoparticles as the nucleation template by the carbonate diffusion method [51]. The crystallization of calcium carbonate in the absence of the 4-MBA capped gold nanoparticles resulted in calcite crystals. This indicates that the polymorphs of CaCOj were controlled by the acid-terminated gold nanoparticles. This result indicates that the rigid carboxylic acid structures can play a role in initiating the nucleation of vaterite as in the case of the G4.5 PAMAM dendrimer described above. 

It is this relative insensitivity that is usually considered as the major drawback of NMR spectroscopy. However, the flexibility of the NMR technique, with the ability to obtain structural information, quantitative data (e.g. kinetic parameters), as well as an indication of molecular volume, using pulsed gradient spin echo (PGSE) NMR diffusion methods [6], makes NMR a most valuable tool. 

Graph used to calculate the point of no net flux for dopamine (DA). Using regression analysis, the extracellular concentration of DA is estimated via the difference method [the DA concentration in the perfusate minus the concentration of DA in the dialysate] plotted against the DA concentration in the perfusate. Values above the zero on the y-axis indicate diffusion to the brain, whereas values below the zero indicate diffusion from the brain. The zero point on the y-axis represents a steady state, at which no net flux of DA occurs across the dialysis membrane and represents the extracellular concentration of DA on the x-axis. Figure from Parsons, L.H., Justice, J.B., Jr. (1994). Quantitative approaches to in vivo brain microdialysis. Crit Rev Neurobiol. 8(3) 189-220... 

The thiophene polyine ( )-2[5-hept-5-en-l,3-diynyl)-thien-2-yl]-ethan-1,2-diol isolated from an ethanolic extract of the underground parts of Leuzea carthamoides DC. demonstrated significant antifungal activity [247], while the dichloromethane extract of the air-dried leaves of Chrysanthemum coronarium afforded N-isobutyl-6-(2-thiophenyl)-2,4-hexadienamide. Fig. (46) [248]. Antimicrobial tests by the agar well diffusion method indicated that it has low activity against Bacillus subtilis. Pseudomonas aeruginosa and Candida albicans, and is inactive against Staphylococcus aureus and Escherichia coli at a concentration of 20 pg/ml. 

Cockeram and Rapp have evaluated the kinetics of silicide coatings on Ti [103] and have used a halide-activated pack-cementation method to form boron- and germanium-doped silicide coatings on orthorhombic alloy substrates [104]. The coatings greatly decreased the cyclic oxidation kinetics and microhardness measurements did not indicate diffusion of oxygen into the substrate. 

Before describing the various indicator-dilution methods, it is useful to recognize that there are two types of indicators, diffusible and nondiffusible. A diffusible indicator will leak out of the capillaries. A nondiffusible indicator is retained in the vascular system for a time that depends on the type of indicator. Whether cardiac output is overestimated with a diffusible indicator depends on the location of the injection and measuring sites. Table 13.1 lists many of the indicators that have been used for measuring cardiac output and the types of detectors used to obtain the dilution curve. It is obvious that the indicator selected must be detectable and not alter the flow being measured. Importantly, the indicator must be nontoxic and sterile. 

We present our study of the new phases, p - and A, -(BEDT-TTF)2l3, which were recently synthesized in our laboratories by a diffusion method. Both of the new organic crystals show a phase transition in their transport properties, and further investigation indicates that the transition is related to the disorder, that possibly exists in these crystals. However, the mechanism of the two phase transitions seems not to be the same. 

Although these authors did not indicate a method for estimating ag, other than from diffusion data, equation (1.18) is one of the most widely used and referred to in the literature. 

The self-diffusion of Cr and Cr isotopes in monocrystals was studied by using ion implantation and thick-film methods. The concentration profiles were determined by using secondary ion mass spectrometry, and the diffusivities were calculated by using a solution to Tick s law which took account of evaporation and exchange at the surface. It was found that both methods indicated diffusion coefficients which were of the same order of magnitude, and could be described by ... 

Berthelot-1 usual FIA method. Berthelot-2 FIA method with a gas diffusion cell. Berthelot-3 FIA stopped-fiow method with a gas-diffusion cell. Indicator- spectrophotometric method (bromothymolblue) with GD cell. Indicator-2 as Indicator-1, but in the stopped-fiow mode. 

The best preparations of CoA give analyses which indicate that there is present, for each mole of pantothenate, 1 mole each of adenine, ribose, and /3-mercaptoethylamine, and 3 moles of phosphate. When these elements are combined with the elimination of 5 moles of water, a calculated molecular weight of 767 is obtained, which is in good agreement with the observed molecular weight obtained by the Northrop Diffusion Method of 800 db... 

Zone of Inhibition A clear area that appears on agar in the disk diffusion method, indicating where the agent has inhibited growth of the organism. 

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