Recording electronics

The type of recording electronics used depends on whether pulsed excitation (either pulse sampling or time orrelated single photon covmting) or phase/ modulation measurement are being made. Therefore, we discuss the electronics in the context of the method. 

In both of the pulse excitation techniques we describe below, the excitation pulse is also used to provide a tri ering signal that the recording electronics uses to synchronize events, hi the case of flash lamp excitation, this is commonly accomplished using an anteima pick-up . For laser pulse excitation. 

For a pre-set number of consecutive pulses, the shutter will always open at the same time tj after triggering and for the same duration tg to allow a small slice (denoted by the hatched area under the decay curve in Hgure 5) of the detector s output signal to enter the recorder. There it is used to charge a capacitor, whose charge increases with each repetition of the pulse. If enough pulses are sampled in this way, random noise in the measured decay segment 

Boxcar averagers and their use in signal recovery are described in (39). PTI (Photon Technology International) manu ctures a series of fluorescence lifetime spectrometers (models C-70 to C-73) that use a stroboscopic detection technique (i.e. a gated PMT, as described in the previous paragraph) and either nanosecond fiashlamp or nitrogen/ e laser excitation. 

Fluorescence decay in a population of excited-state molecules is a random process, so that the arrival time of the first photon is also random, although it is more likely to occur at the peak of the fluorescence decay than it is along the latter s tail. Because of this inherent statistical nature, over many excitation cycles one gradually builds us a statistical profile of the likelihood of emission versus time that corresponds to the decay profile. For a large enough number of counts, the uncertainty in the number of counts in a particular channel is equal to the count number s square root, which gives us the weighting factors to be used in the least-squares analysis of the data. 

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Except for the phase-contrast detector in STEM [9], STEM and SEM detectors do not track the position of the recorded electron. The spatial information of an image is fonned instead by assigning the measured electron current to the known position of the scaimed incident electron beam. This infomiation is then mapped into a 2D pixel array, which is depicted either on a TV screen or digitalized in a computer. 

Reaction (3) represents a metal wire connected by one side to a piece of electronic equipment able to produce and record electronic signals. The... 

Drug, and Cosmetic Act and the Fair Packaging and Labeling Act. Color additives. Part 11 Electronic Records Electronic Signatures... 

Documentation - procedures, specifications, retention of records, electronic data... 

FDA Guidance Guidance for Industry Part 11, Electronic Records Electronic... 

FDA. Code of Federal Regulations, Title 21 Food and Drugs, Part 11 Electronic Records Electronic Signatures Final Rule, Fed Regr 62 (54), 13429-13466 (20 March 1997). 

FDA. Withdrawal of draft guidance for industry on Electronic Records Electronic Signatures, Electronic Copies of Electronic Records, Fed Regr 68 (23), 5645 (4 February 2003). 

FDA. Draft Guidance for Industry on Part 11, Electronic Records Electronic Signatures—Scope and Application Availability of Draft Guidance and Withdrawal of Draft Part 11 Guidance Documents and a Compliance Policy Guide, Fed Regr 68 (37), 8775-6 (25 Eebruary 1997). 

Electronic Records, Electronic Signatures Final Rule, 21 CFR Part 11, Federal Register, Vol. 62, No. 54, US Food and Drug Administration, Rockville, MD (1997). Also available on the World Wide Web http //www.fda.gov/ora/compliance refypartll/default.htm. 

Determination that persons who develop, maintain, or use electronic record/electronic signature systems have the education, training, and experience to perform their assigned tasks. ... 

CFR - Part 11 means that you must be qualified to do your work, your programming must be validated, you must have system security in place, and you must have change control procedures for your SAS programming. The current additional FDA guidance on 21 CFR - Part 11 is titled Guidance for Industry Part 11, Electronic Records Electronic Signatures—Scope and Application. ... 

FDA Guidance for Industry, Part 11, Electronic Records Electronic Signatures - Scope and Application (Final version, August 2003), Center for Dmg Evaluation and Research (CDER), US Food and Drug Administration (FDA), Beltsville, MD, USA, 2003. 

The use of an automatic polari-meter with a flow-cell has been reported by de Ros il26,to monitor the eluate from an ion-exchange column (Bio-Rad AG1-X2) through which a solution of neomycin was passed. The detection of an optically active substance was recorded electronically with a suitable pen recorder. By determining the areas of the peaks recorded, the amounts of neomycins B and C and neamine in a number of commercial samples have been determined. 

Exhibit 9.8 21 CFR Part 11 Electronic Records Electronic Signatures— Maintenance of Electronic Records... 

Title 21 Code of Federal Regulations (21 CFR Part 11), Electronic Records Electronic Signatures, FDA, 2003 (http //www.fda.gov). Validation/compliance documents found under the Parenteral Drug Association (PDA) (http //www.pda.org). 

CFR 21 Part 11, Electronic Records, Electronic Signatures - Scope and Application... 

CHECKLIST 21 CFR PART 11 Electronic Records-Electronic Signatures... 

So far, we have seen that if we measure the Bragg angle of the reflections and successfully index them, then we get information on the size of the unit cell and, if it possesses any translational symmetry elements, also on the symmetry. In addition, we have seen that the intensity of each reflection is different and this too can be measured. In early photographic work, the relative intensities of the spots on the film were assessed by eye with reference to a standard, and later a scanning microdensitometer was used. In modern diffractometers, the beam is intercepted by a detector, either a charge coupled device (CCD) plate or a scintillation counter, and the intensity of each reflection is recorded electronically. 

GUIDANCE FOR INDUSTRY PART 11. ELECTRONIC RECORDS ELECTRONIC SIGNATURES- SCOPE AND APPLICATION... 

U.S. Food and Drug Administration (FDA) (2003), Guidance for industry, CFR Part 11, Electronic records electronic signatures, good manufacturing practices, FDA, Rockville, MD. 

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