Threshold testing

Three male squirrel monkeys previously trained to perform visual discrimination or visual acuity threshold tests were exposed continuously for 90 d to PGDN at a concentration of 262 mg/m3 (approximately 37 ppm) (Jones et al. 1972). The animals were removed from the exposure chambers for a 2-h period once a week for the respective behavior tests. A fourth trained monkey exposed to filtered room air under the same conditions served as the control. The only sign during exposure was mydriasis (excessive dilatation of the pupil of the eye), which increased from slight to moderate. There were no changes in avoidance behavior in the monkeys as determined by the visual tests. 

With the standardisation of threshold tests generally for other taste and aroma stimuli, pungency testing has also improved, and we can now get reliable and reproducible measurements of pungency. 

Borkowski GL, Dannemann PJ, Russel GB, Lang CM (1990) An evaluation of three intravenous regimens in New Zealand rabbits. Lab Anim Sci 40 270-276 Glenn JB (1980) Animal studies of the anesthetic activity of ICI 35868. Br J Anaesth 52 731-742 Korkmaz S, Wahlstrom G (1997) The EEG burst suppression threshold test to determine the CNS sensitivity to intravenous anesthetics in rats. Brain Res Prot 1 378-384... 

Figure 32-11 Visual field results obtained with static threshold testing in a 71-year-old woman with acute class 6 Graves ophthalmopathy. (A) Central and paracentral defects in left visual field are associated with 20/60 (6/18) visual acuity...

The Threshold Test Ban Treaty of 1974 limited the yield of underground nuclear weapon tests to 150 kilotons (the equivalent of the explosive force of approximately 150,000 tonnes of trinitrotoluene (TNT). 

The evaluation of odor has been of great importance in the study of potable water, and there the Spaulding Threshold Test is extensively used. This test was invented by Charles Spaulding3 and further developed by Braidech,6 Laughlin,7 Feben,8 Hulbert,8 and others.9... 

A number of animal models are currently available for anticonvulsant screening [13,14]. Two basic models used are Maximal Electroshock Test (MEST) and Subcutaneous Pentylenetetrazole Seizure Threshold Test (ScMET). Anticonvulsant activity in MEST predicts the ability of the testing material or compound in preventing the spread of seizure discharge and effectiveness in the treatment of grandmal seizures, while activity in ScMET predicts the ability to elevate seizure threshold and effectiveness in myoclonic seizures. 

Robinson, K.M. B.P. Klein S.Y. Lee. Utilizing the R-index measure for threshold testing of model soy isoflavone solutions./. Food Sci. 2004, 69, SNQl-4. 

Seabed Treaty 1972 94 countries prohibits emplacing nuclear weapons or weapons of mass destruction on the sea bed and the ocean floor beyond the 12- mile coastal zone. Threshold Test Ban Treaty (TTBT) 1974 United States, USSR prohibits underground nuclear tests having a yield exceeding 150 kilotons. South Pacific Nuclear Free-Zone Treaty (Treaty of Rarotonga) 1985 15 countries prohibits testing, deployment, or acquisition of nuclear weapons in the South Pacific. 

Typically panel members are presented spiked beers (particular flavor characteristics added to a sample) alongside a standard beer (a control with no perceived defect) to understand the flavors versus a true-to-brand sample. Any material added to beer intended for human consumption must be food-grade quality and safe, to avoid any health hazard. The threshold values mentioned in Table 18.3 were based on light-style lagers, and as such, levels may have to be increased to accommodate their perception in more flavorful craft beers. Indeed threshold tests will become a part of routine sensory training practice, especially with more flavorful beers. Details on such testing are covered in many of the references that we cite in this section. 

Figure 7.1 shows human subject threshold tests for left, right and left and right combined nostrils conducted on the inkjet-based digital dispenser. 

Threshold testing is a two-step process. First the LV threshold is determined. If unacceptable or complicated by diaphragmatic stimulation, the lead requires adjustment or repositioning. If the LV threshold is acceptable, the biventricular threshold is then determined. Unless dual bipolar leads are used, threshold testing is carried out in the unipolar configuration. Threshold testing... 

Fig. 7.5 Threshold testing. The first three stimuli are delivered with 1 mA output. The third pacing stimulus (arrow) does not result in ventricular depolarization. The output is increased slightly to 1.25 mA and consistent capture is observed.

Disable ICD therapies and detection algorithms in patients with these devices and have standard transthoracic defibriUation methods readily available. Perform full interrogation of ICD function including threshold testing and measurement of lead impedances. It is imperative to confirm that tachycardia therapies have been reinstituted after the procedure. 

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