Principal-agent

Regardless of the source, the resultant oil slicks are essentially surface phenomena that are affected by several transportation and transformation processes. With respect to transportation, the principal agent for the movement of slicks is the wind, but length scales are important. Whereas small (i.e. relative to the slick size) weather systems, such as thunderstorms, tend to disperse the slick, cyclonic systems can move the slick essentially intact. Advection of a slick is also affected by waves and currents. To a more limited extent, diffusion can also act to transport the oil. 

The pigment is the principal agent in the electrochemical control of corrosion by primers (see Section 14.3). Probably the best known anticorrosive pigment is red lead. When used in conjunction with linseed oil as the binder it gives very good primers which will perform well over relatively poorly prepared (manually abraded) steel surfaces. Present-day use of red lead (and lead pigments, generally) in paints has been drastically curtailed as a result of understandable pressure from the environmentalists. 

The principal agents of tooth decay are the carboxylic acids produced when bacteria act on the remains of food. A more resistant coating forms when the OH ions in the apatite are replaced by F ions. The resulting mineral is called fluorapatite ... 

Water can usually be used as an ingredient, a solvent, and a principal agent for cleaning and disinfection in plants or transportation systems for delivering raw materials. Since water consumption will always be a part of the food processing industry, it has become the key target for pollution prevention and source reduction practices. 

Quartz is one of the most common minerals in the sedimentary rocks typically associated with coal. A relatively inert mineral, quartz does not significantly affect the acid-alkali balance of pore waters, and to that extent it is environmentally neutral . On the other hand, quartz is the principal agent of silicosis, which is one of the most severe respiratory health problems associated with coal mining. 

The quantitative estimation may be made, more or loss correctly, by one of four methods 1. By determining tlie specific gravity of the ore or alloy 2. By the touchstone 8. By chemical analysis, or the wet method of assaying and 4. By the metallurgical, or (fry method, in which fire is tlie principal agent. The first two afford only approximations, and the second is applicable only to alloys of gold but both may be useful when circumstances render impossible or inconvenient the performance ol an exact assay by the wet or dry method. 

At present, hippuric acid, PhC(0)NHCH2C02H, labelled in the ortho position with 131I, is the principal agent used for evaluating renal tubular secretory function, but the nuclear properties of 131I or l23I are far from ideal for this purpose.665,667 This has stimulated the search for a "Tc... 

In terms of the percipients votes for the target actually traveled to, the experiment was a failure. Yet, the viewers choices showed a clear preponderance of first and second choices for the mortuary (the target site that the principal agent had strongly wanted to go to), a second-place vote for the room in the art museum (where the agents had been supposed to go), and a third-place vote for the church (the site they had actually visited). The coaches separate votes and the team votes also showed a preference for the mortuary, with the room in the art museum and the church also getting a very high number of votes. 

It was surmised that X-ray-induced base damage would lead mostly to recessive lesions and that the significant damage in cells other than haploids was, therefore, of a different nature. In due course, it was shown that the principal agent of lethality was the formation of double-strand breaks, since in strains defective in doublestrand break repair, inactivation and the induction of double-strand breaks were in a 1 1 ratio (Ho, 1975). 

Type of Infection Aspergillosis Principal Sites of Infection Lungs, other organs, body orifices Principal Agent(s) Amphotericin B Secondary/Alternative Agent(s) Itraconazole, voriconazole... 

In 2000, heroin was second only to cocaine in the number of drug-related emergency room episodes reported to a national registry run by the Drug Abuse Warning Network. Heroin, listed as a principal agent in respiratory and cardiac emergencies, went from 33,884 episodes nationwide in 1990 to 94,804 in 2000—an increase of nearly 180%. 

Dunlop, C. A. O. James (2007) Principal-agent modelling andleaming the European Commission, experts and agricultural hormones , Public Policy and Administration 22(4) 403 122. 

The principal agents for treating acute left ventricular failure arc frusemide (furosemide). diamorphine and oxygen. 

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