Sensing indirect

Cu(II) spectral intensities for Samples 1-3 were in the order of Sample 3 > Sample 2 > Sample 1. Although ESR spectrometry in general is semi-quantitative in nature, the order of the spectral intensity was consistent with the amount of Cu(II) on the microspheres as determined by the Cu(II) adsorption study. The imprinting effect or an enhanced Cu(II) adsorption behaviour as indicated by the metal adsorption test is in a sense indirect, because it only shows the decrease in Cu(II) concentration in a test solution. Meanwhile, the presented ESR spectra directly indicated such an enhanced Cu(II) adsorption and complex chemical structure of the adsorbed Cu(II) species in the Cu(II)-imprinted microspheres. 

Some analyte chemical species are themselves capable of exhibiting optical changes related to their concentrations, which can be measured photometrically using optical fibers. Such sensors, in which separate chemical transduction systems will not be required, are commonly referred to as plain-fiber sensors. Since many analytes do not themselves possess suitable optical characteristics, they may be sensed indirectly through their interaction with an appropriate chemical transduction system. The sensor response function in such chemical transducer-based optical sensors depends on the manner in which the analyte interacts with the reagent phase. For example, in a simple system where a reagent R reacts with an analyte species A forming a product AR can be represented by the reaction... 

The extracellular calcium Ca -sensing receptor plays a central role in maintaining a nearly constant level of extracellular calcium by sensing small changes in Ca and directly and/or indirectly altering the translocation of calcium ions into or out of the extracellular fluid so as to normalize CaQ+. Changes in the level of expression and/or function of the CaR reset the level of CaQ+. Recently developed activators (calcimimetics)... 

This equation has been derived only as a reference for a comparative discussion of data for sd- and d-metals later on. However, the meaning of such a line is that there exists a limit to AX values in the sense that after a given top effect, a further increase in metal-water interaction will not produce higher AX values.6,7 An indirect confirmation of this is given by the observation of a top value in the decrease of 0 upon water adsorption on d-metals from the gas phase.35,36... 

Myositis may also have an infective basis. Viral myositis has been recorded in association with influenza and picomavirus infections, particularly those due to viruses of the Coxsackie group, and HIV infection is an increasingly common cause of myositis seen in routine practice. Fungal, bacterial, and parasitic myositis is seen much more rarely in North America and Europe than in tropical parts of the world, but in these regions these forms of infective myositis constitute a significant problem. In any survey of inflammatory muscle disorders, it is also necessary to consider other inflammatory conditions which affect muscle indirectly, but do not cause myositis in the strict sense of the word. In this group are to be found various forms of arteritis and fascitis and granulomatous conditions such as sarcoidosis. 

The second perspective might be that of the leader of some large project where chemical analyses are just a side issue, where sample numbers are large and chemical niceties might be completely swamped by, say, biological variability here a statistician will be necessary to make sense of the results in the context of a very complex model. Chemistry is a bit harder to relate to than many other industries in that the measured quantities are often abstract, invisible, and only indirectly linked to what one wants to control. 

Foil of PTFE or polythene Chemical reagent + glass membrane Gas-sensing electrode H+ (or OH -) as an indirect measure of NH3, S02, nitrous vapours, H2S, HCN, CMXa), C02... 

Indirectly actuated valves pneumatically or electrically operated valves, which are activated by pressure-sensing instruments. 

Today, the first question can sometimes be studied directly using techniques that are described in later chapters, but this was not an option for the early pharmacologists. Also, the only responses that could then be measured (e.g., the contraction of an intact piece of smooth muscle or a change in the rate of the heart beat) were indirect, in the sense that many cellular events lay between the initial step (activation of the receptors) and the observed response. For these reasons, the early workers had no choice but to devise ingenious indirect approaches, several of which are still important. These are based on modeling (i.e., making particular assumptions about) the two... 

Composition is another variable that is often measured indirectly. A temperature-sensing device is often used at the top of an atmospheric distillation... 

Eugene Dowdle. You have not mentioned the effects of Medical Aid schemes on physician-physician and physician-patient relationships. One of the keystones of the Oslerian ethic was the sense of collegiality that bound the medical profession and provided, indirectly, a form of peer review that was of benefit to both patients and to medical practitioners. Medical Aid schemes, by their monetarising effects, have done much to damage those professional bonds. 

This section covers early indirect fiber optic chemical sensors (FOCS) for species that cannot be sensed directly but require the use of indicators, probes, labeled biomolecules, or color-forming reactions. 

Gas detection methods may be split into two groups, (i) direct methods, which monitor a physical parameter of the target gas, and (ii) indirect methods, which use a chemical reaction or indicator to show the concentration of the gas being sensed. This division of methods may be further split into optical sensing techniques and non-optical techniques. This review will predominantly focus on direct optical-spectroscopy fibre sensing techniques. 

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