Array scan

Figure 6.19 (a) Diode array scan and (b) precursor ion scan m/z 112. 

The first functional cell-based assay for the determination of pan-histone deacetylase activity was achieved by detecting hyperacetylated histones by Western blotting. The histone acetylation level in cells offers a measure of candidate HDACI activity and has been linked to antiproliferative and cytotoxic effects. Beckers et al. used a cellular histone hyperacetylation assay for quantification of the cellular efficacy of HDACIs using the Cellomics Array Scan II platform in 96 wells [14]. The program... 

Array scanning and analysis ScanArray Express (PerkinElmer, Torrance, CA). 

A top view of a focal plane array is shown above. Metallic traces 24 are aligned parallel to the focal plane array scan axis. Each of the metallic traces is terminated at a peripheral portion of the array with a contact pad 42 having an indium bump interconnect 44 disposed thereon. The placement of indium bumps separately from the active areas of the focal plane array permits these to be shielded from the scanned radiation. Unwanted reflections from the contact pads and the indium bump interconnects are therefore reduced or eliminated. 

Microscopic imaging and analysis readers such as EvoTec s Opera, General Electric s INCell Analyzer 3000, Cellomics Array Scan, Acumen s Explorer, and Molecular Devices ImageXpress transform the data from each well into a fluorescent microscopic... 

Trask, O.J., Jr. et al. 2006. Assay development and case history of a 32K-biased library high-content MK2-EGFP translocation screen to identify p38 mitogen-activated protein kinase inhibitors on the Array Scan 3.1 imaging platform. Meth. Enzymol. 414, 419-439. 

The pixel circuit requirements for the scanner are similar to those of the liquid crystal display. A 300 spi array scanning an image at 3 inch s must read each line in a time of 1 ms. For a matrix of 50 gate and data lines, each pixel is addressed for 20 ps. The capacitor of the sensor is about 1 pF (note that 300 spi corresponds to a pixel of about 80 pm which is smaller than in the liquid crystal example). The required TFT current of 1 pA is easily obtained. The low oflF-current of the TFT also ensures that the charge will not leak away between being read out. 

Recently a number of advanced detection methods have been introduced such as multi-wavelength evaluation or measuring the UV spectra by diode-array scanning [86,87]. fluorodensitometry. voltammetry, and fast atom-bombardment mass spectrometry. etc. 

In the ArrayExpressC model, the description of the array scanning and analysis allows for many-to-many relationships between the array elements and expression values. 

SPD. When high quality devices are used, readout lag of SPDs is very small for light levels below the capacitance saturation of the diodes, i.e., approximately 2 x 10° photons/diode. Above that light level, charge diffuses to the substrate and a few array scans may be necessary to fully read it off the target. It is interesting to note that the vidicon lag is due to incomplete readout of small signals, whereas the reverse is true for SPDs. 

Fig. 25. Schematic diagrams of (A) conventional and (B) diode array scanning spec-trophometers operated in the dispersion mode. (A) The spectrum is dispersed by a grating or prism (the dispersing element) and scanned across an exit slit. A single-element detector (usually a photomultiplier tube) is used to measure the intensity of a monochromatic beam after it passes through the sample. (B) The sample is illuminated with white light prior to dispersion. The dispersed spectrum is imaged on a linear array detector, and the signals from individual elements provide the information necessary to generate spectral information. [Redrawn from Santini et al. (134) with permission.]...

The detector arrays scan the subject for normal whole-body counting, but the scanning detector geometry can... 

Figure 6 A (a) Schematic of the formation of tubular (single or multiwalled), spherical, or fihrillar structures via dipeptide self-assembly, (b) Proposed model for the formation of aligned peptide nanotube arrays. Scanning electron micrograph of (i) the vertically aligned peptide nanotubes, (ii) the nanotube arrays, and (iii) an individual nanotube obtained. Reprint with permission from Ref. [7].

R. C. Hansen, Finite Array Scan Impedance Gibbsian Models, Radio ScL, Vol. 31, November-December 1996, pp. 1631-1637. 

R. C. Hansen and E. Raudenbush, Modulated Oscillations in Finite Array Scan Impedance, in Proceedings of the IEEE Symposium on Phased Array Systems, Boston, 1996. 

FIGURE 13 Two-dimensional imaging, (a) Single-element scan, (b) Line array scan, (c) Staring array. 

For example, the above sample, when examined by XPS, showed a composition of 51% Bi, 39% V, and 10% W, within experimental error to the dispensed ratio, with peaks consistent with oxidation states +3, +5, and +6, respectively. The bulk film PEC studies agreed with the array scans and showed improvements in photocurrent in both the UV-visible and visible region by factors of 3-4. 

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