Resistivity monitoring

Electrical resistance monitors use the fact that the resistance of a conductor varies inversely as its cross-sectional area. In principle, then, a wire or strip of the metal of interest is exposed to the corrodent and its resistance is measured at regular intervals. In practice, since the resistance also varies with temperature, the resistance of the exposed element is compared in a Wheatstone bridge circuit to that of a similar element which is protected from the corrodent but which experiences the same temperature. 

The Danish Integrated Antimicrobial Resistance Monitoring and Research programme... 

NARMS/USA National Antimicrobial Resistance Monitoring System (United States of America)... 

Danish Integrated Antimicrobial resistance Monitoring and Research Programme (DANMAP-Denmark) Available from http //www.dairmap.org/ (30 August 2011)... 

The electrical resistance (ER) method to monitor physical changes in an electrically conducting material is well known(6). 10 cm x 2.5 cm coated iron foils of 10 micron thickness were electrically resistance monitored during exposure to various corrosive environments to follow metal thickness loss at the paint/metal interface. The circuit shown in Figure 1 allowed foil resistance increase AR, which is directly related to metal thickness loss Ad according to Equation (1), to be determined within 0.003 microns. 

The treatment of HP has become increasingly difficult due to the frequency of antibiotic resistance and recurrence after successful treatment. In Peru, the recurrence rate of the infection is as high as 73% even after successful eradication. In this instance, recurrence is not attributed to antibiotic resistance but to re-infection of patients. In the United States, resistant HP is also of concern. The Helicobacter pylori Antimicrobial Resistance Monitoring Program (HARP) is a multicenter US network that tracks HP patterns of resistance. In 2004, HARP reported that 34% of 347 HP isolates tested were resistant to one or more antibiotics commonly used to treat HP infections.In the US, most antibiotic resistance is associated with metronidazole and clarithromycin, both standard treatment options for HP. Thus, antibiotic resistance and high re-infection rates strongly argue for the development of new therapeutic modalities to prevent and treat HP infections worldwide. 

Noise resistance monitoring has been used to track the long-term degradation of marine coatings under laboratory exposures (153), and remotely under natural exposure conditions (154). In studies of epoxy and alkyd coatings on steel... 

Considering the limited number of pesticides developed in recent years and the need to extend the useful life of the available compounds, WHO, in collaboration with other relevant institutions, should strengthen pesticide resistance monitoring in vectors and pests of public health importance and promote effective and practical resistance management strategies. 

Roush, R.T. and Miller, G.L., Consideration for design of insecticide resistance monitoring programs, /. Econ. Entomoi., 79, 293,1986. 

Unpattemed electroplated copper wafers were polished using an IPEC 472 polisher equipped with an IR temperature sensor which measures pad surface temperature. The copper rate was determined from copper thickness measurements from a Tencor RS55 resistance monitor, calibrated to cross-sectional SEM micrographs. The SEM tools are regularly calibrated to national standards. 

Table 4 National antimicrobial resistance monitoring system animal isolates (chicken slaughter d isolates)...

NARMS Brochure National Antimicrobial Resistance Monitoring System—Enteric Bacteriahttp //www.fda. gov/cvm/index/narms/narmsbro.htm (accessed 02-23-04). 

Figure 4. Variation in pre-bake ( ) and post-bake ( ) sheet resistance with percent chromium for a fixed value of the resistance monitor. The films were baked at 300°C for 30 min. in air.

Progress in research on resistance mechanisms with emphasis on gene amplification and Diagnostic tests for resistance monitoring. 

Ue now consider the main technical factors underlying attempts at resistance management resistance mechanisms, cross tolerance/resistance, and resistance monitoring. 

The magnitude of the present annual resistance monitoring effort on the part of the PEG-US group, as well as state and federal researchers, is unprecedented as far as field crop pests are concerned and reflects the serious concern within the cotton industry that pyrethroid resistance could get out of control. These monitoring efforts have shown a general trend in some areas to increased tolerance of tobacco budworms to pyrethroids, as well as an expansion of the geographical area within which such increased tolerance has been detected. However, except for the aforementioned incidents there have been no documented failures in field control. 

III. Use Resistance Monitoring to Study Resistant Populations. Sensitivity monitoring used to determine the level and frequency of resistant strains is needed in guiding fungicide use strategies. 

Integrate a resistance monitoring system into other management/monitoring practices. 

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