CMOS integrated pixel array for low-level radiation detection using ‘time compression’ parametric amplification

Daniel Durini; Armin Kemna; Werner Brockherde; Bedrich J. Hosticka

doi:10.1016/j.nima.2006.05.263

CMOS integrated pixel array for low-level radiation detection using ‘time compression’ parametric amplification

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2006.05.263 ◽

2006 ◽

Vol 568 (1) ◽

pp. 112-117 ◽

Cited By ~ 4

Author(s):

Daniel Durini ◽

Armin Kemna ◽

Werner Brockherde ◽

Bedrich J. Hosticka

Keyword(s):

Radiation Detection ◽

Parametric Amplification ◽

Low Level ◽

Time Compression ◽

Pixel Array

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Experimental Image of Pinhole Using CdZnTe Detector

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.321-324.935 ◽

2013 ◽

Vol 321-324 ◽

pp. 935-939

Author(s):

Min Shen

Keyword(s):

Imaging System ◽

Radiation Detection ◽

High Sensitivity ◽

Nuclear Radiation ◽

Array Detector ◽

Nuclear Medical Imaging ◽

Imaging Detector ◽

Pixel Array ◽

Pinhole Imaging ◽

Experimental Image

The imaging detector of the nuclear radiation is applied widely in radiation detection, the safety monitor and nuclear medical imaging. We aimed to make scientific researches on nuclear radiant source through the pinhole imaging system .The imaging system was designed that base on the Imarad 16×16 pixel-array CdZnTe semiconductor detector. The detector has high sensitivity to low energy under 200kev at room temperature. We applied the detector and pinhole system to obtain the image of the radiant source that the energy was up 200kev.The detection efficiencies of 38.92 mm×38.92 mm by 5 mm thick CdZnTe pixel-array detector were measured. The capability of the whole system was test and evaluated. The rough image of the radiant source was achieved through the test. When the location of the source and pinhole parameter were changed, the image would vary correspondingly. The accurate image could acquired by means of image reconstruction .So it is feasible that the research about the localization and qualification of the nuclear radiation is making use of the pinhole system.

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Nonlinear Distortions and Parametric Amplification Generate Otoacoustic Emissions and Increased Hearing Sensitivity

Acoustics ◽

10.3390/acoustics1030036 ◽

2019 ◽

Vol 1 (3) ◽

pp. 608-617

Author(s):

Frank Böhnke

Keyword(s):

Traveling Wave ◽

Mechanical Model ◽

Otoacoustic Emissions ◽

Outer Hair Cell ◽

Basilar Membrane ◽

Parametric Amplification ◽

Outer Hair Cells ◽

Cell Stiffness ◽

Low Level ◽

Nonlinear Distortions

The ear is able to detect low-level acoustic signals by a highly specialized system including a parametric amplifier in the cochlea. This is verified by a numerical mechanical model of the cochlea, which reduces the three-dimensional (3D) system to a one-dimensional (1D) approach. A formerly developed mechanical model permits the consideration of the fluid and the orthotropic basilar membrane in a 1D fluid-structure coupled system. This model shows the characteristic frequency to place transformation of the traveling wave in the cochlea. The additional inclusion of time and space dependent stiffness of outer hair cells and the signal level dependent stiffness of the string enables parametric amplification of the input signal. Due to the nonlinear outer hair cell stiffness change, nonlinear distortions follow as a byproduct of the parametric amplification at low levels constituting the compressive nonlinearity. More distortions are generated by the saturating displacements of the string at high input levels, which can be distinguished from the low-level distortions by the order of additional harmonics. Amplification factors of 15.5 d B and 24.0 d B are calculated, and a change of the traveling-wave mapping is postulated with parametric amplification representing the healthy state of the cochlea.

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Tryptophan-Niacin Metabolism in Rat with Puromycin Aminonucleoside-Induced Nephrosis

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.76.1.28 ◽

2006 ◽

Vol 76 (1) ◽

pp. 28-33 ◽

Cited By ~ 7

Author(s):

Yukari Egashira ◽

Shin Nagaki ◽

Hiroo Sanada

Keyword(s):

Body Weight ◽

Urinary Excretion ◽

Enzyme Activities ◽

Treated Group ◽

Control Group ◽

Puromycin Aminonucleoside ◽

Low Level ◽

Key Enzyme

We investigated the change of tryptophan-niacin metabolism in rats with puromycin aminonucleoside PAN-induced nephrosis, the mechanisms responsible for their change of urinary excretion of nicotinamide and its metabolites, and the role of the kidney in tryptophan-niacin conversion. PAN-treated rats were intraperitoneally injected once with a 1.0% (w/v) solution of PAN at a dose of 100 mg/kg body weight. The collection of 24-hour urine was conducted 8 days after PAN injection. Daily urinary excretion of nicotinamide and its metabolites, liver and blood NAD, and key enzyme activities of tryptophan-niacin metabolism were determined. In PAN-treated rats, the sum of urinary excretion of nicotinamide and its metabolites was significantly lower compared with controls. The kidneyα-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) activity in the PAN-treated group was significantly decreased by 50%, compared with the control group. Although kidney ACMSD activity was reduced, the conversion of tryptophan to niacin tended to be lower in the PAN-treated rats. A decrease in urinary excretion of niacin and the conversion of tryptophan to niacin in nephrotic rats may contribute to a low level of blood tryptophan. The role of kidney ACMSD activity may be minimal concerning tryptophan-niacin conversion under this experimental condition.

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