Tolerances background

Zhu, P. et al., A retention-time-shift-tolerant background-subtraction and noise-reduction algorithm (BgS-NoRA) for extraction of drug metabolites in LC-MS Data, in Proceedings of the 57th ASMS Conference on Mass Spectrometry and Allied Topics, ASMS, Philadelphia, PA, 2009. 

Table 5 shows the noise rates per module which ensure that a fluctuation to the 10 event level in any 10 second period in the entire array occurs less than once per century. Comparison of these target event rates with various background estimates allows restrictions to be placed on the range, contamination levels and construction depth of fission burst detectors. As before, relaxing the background restriction to allow one false positive per year rather than per century has only a modest effect on the tolerable background noise level. For example, the allowable noise at 1000 km becomes 1.1 events per day instead of 0.7. 

For a signal based on measurement of the positron alone, the background is taken to be any event detectable by Cerenkov radiation and depositing 2 MeV or more of energy in the detector. At ranges down to about 10 km, we v l see that backgrounds from uranium, thorium, and radon contamination in the water exceed the tolerable background rates just defined. This restriction is relaxed considerably by the addition of a dopant. 

There are important figures of merit (5) that describe the performance of a photodetector. These are responsivity, noise, noise equivalent power, detectivity, and response time (2,6). However, there are several related parameters of measurement, eg, temperature of operation, bias power, spectral response, background photon flux, noise spectra, impedance, and linearity. Operational concerns include detector-element size, uniformity of response, array density, reflabiUty, cooling time, radiation tolerance, vibration and shock resistance, shelf life, availabiUty of arrays, and cost. 

The FDA requests that the method exhibit sufficient sensitivity to measure accurately the residue of interest after fortification of the control matrix at half the tolerance concentration. Minimally, the detector response at the tolerance should be at least 10 times the average background response. 

OPPTS 860.1000 Background OPPTS 860.1100 Chemical Identity OPPTS 860.1200 Directions for Use OPPTS 860.1300 Nature of Residue - Plants, Livestock OPPTS 860.1340 Residue Analytical Method OPPTS 860.1360 Multiresidue Method OPPTS 860.1380 Storage Stability Data OPPTS 860.1400 Water, Fish, Irrigated Crops OPPTS 860.1460 Food Handling OPPTS 860.1480 Meat/Milk/Poultry/Eggs OPPTS 860.1500 Crop Field Trials OPPTS 860.1520 Processed Food/Feed OPPTS 860.1550 Proposed Tolerances... 

Generally, younger patients with a better performance status tolerate chemotherapy better than elderly patients. Caucasian women tend to have a worse prognosis and response to therapy compared with other ethnic backgrounds.2,4,5... 

Anthropogenic use of mercury should be curtailed, because the difference between tolerable natural background levels of mercury and harmful effects in the environment is exceptionally small... 

The substance to be determined need not itself absorb whilst a degree of background absorbance or turbidity can be tolerated. 

In summary, therefore, the ability to tolerate dietary exposure to food proteins does not demand the suppression of all immune responses, but rather the avoidance or selective inhibition of immune responses of the quality required for IgE antibody production and allergic sensitization. Against this background an intriguing question relates to the nature of factors that influence the loss or failure of immunological tolerance and acquisition of allergic sensitization to food proteins, and which underlie inter-individual differences in susceptibility to food allergy [43],... 

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