Search results
Results from the WOW.Com Content Network
The Kastle–Meyer test is a presumptive blood test, first described in 1903, in which the chemical indicator phenolphthalein is used to detect the possible presence of hemoglobin. It relies on the peroxidase -like activity of hemoglobin in blood to catalyze the oxidation of phenolphthalin (the colorless reduced form of phenolphthalein) into ...
Test cards typically contain a set of patterns to enable television cameras and receivers to be adjusted to show the picture correctly (see SMPTE color bars).Most modern test cards include a set of calibrated color bars which will produce a characteristic pattern of "dot landings" on a vectorscope, allowing chroma and tint to be precisely adjusted between generations of videotape or network feeds.
A precursor to the SMPTE test pattern was conceived by Norbert D. Larky (1927–2018) [5] [6] and David D. Holmes (1926–2006) [7] [8] of RCA Laboratories and first published in RCA Licensee Bulletin LB-819 on February 7, 1951. U.S. patent 2,742,525 Color Test Pattern Generator (now expired) was awarded on April 17, 1956, to Larky and Holmes. [9]
A positive result induces a color change to pink. [4] Similar to the Kastle-Meyer test, a hemastix is also a catalytic test simplified to a specialized strip where the blood sample is extracted by a wet swab and placed directly on the hemastix. [7] A positive result induces a colour change from yellow to dark green. [7]
For televisions the picture line-up generation equipment (PLUGE or pluge) is a greyscale test pattern used in order to adjust the black level and contrast of the picture monitor. Various PLUGE patterns can be generated, the most common consisting of three vertical bars of super-black, normal black, and near-black and two rectangles of mid-gray ...
As Televisión Española adopted the PAL colour system in 1975, [4] [5] the test card has specific elements that allow proper colour adjustments. Being a creation of the same team behind the Philips PM5544 test card, [8] [9] it has many elements in common with it (like colour and grey bars or castellations [10]), but introduces some differences (for example, different resolution gratings and ...
An exit to the West Front of the U.S. Capitol building is pictured on the day it was announced U.S. President-elect Donald Trump's inauguration is being moved indoors due to dangerously cold ...
Most people who take a drug test take a presumptive test, cheaper and faster than other methods of testing. However, it is less accurate and can render false results. The FDA recommends for confirmatory testing to be conducted and the placing of a warning label on the presumptive drug test: "This assay provides only a preliminary result.