Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haemathological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogeneti...
National Technical Information Service (NTIS)
Several methods of bone marrow dose calculation for photon irradiation were analyzed. After a critical analysis, the author proposes the adoption, by the Instituto de Radioprotecao e Dosimetria/CNEN, of Rosenstein's method for dose calculations in radiodi...
This paper reviews the state-of-the-art in pulsed radiation dosimetric techniques. A comparative analysis, based on test results from experiments conducted at the Casaccia research labs of ENEA (the Italian Agency for New Technology, Energy and the Enviro...
Fission track dating is described, focalizing the problem of the decay constant for spontaneous fission of (sup 238) U and the use of neutron dosimetry in fission track analysis. Experimental procedures using thin films of natural uranium as neutron dosim...
A method for the numerical analysis of complex termoluminiscence glow curves based in a modified Marquard Levenberg minimization algorithm is presented. Differents analytical expresions are employed for the individual glow peaks in the cases of first, sec...
... If the incident beam contains aberrations, the shape and ... or gaussian intensity distribution and containing defocus and/or spherical aberration. ...
DTIC Science & Technology
... the Gaussian reference sphere centered at the geometrical image ... summation of specific kinds of single aberrations, and each aberration has a ...
... However, a controlled aberration can be used as an indicator just as chromatic aberrations in a prism are essential for spectroscopy. ...
... farsightedness and spherical aberration as they affect shooting performance. ... In his dis- cussions of spherical aberration, he identified the need to ...
In October 2009, the International Atomic Energy Agency (IAEA) sponsored an intercomparison exercise of surface contamination monitoring equipment, which was held at the Laborat�rio Nacional de Metrologia das Radia��es Ionizantes, from the Instituto de Radioprote��o e Dosimetria, IRD/CNEN, Rio de Janeiro. This intercomparison was performed to evaluate the calibration ...
PubMed
The report discusses the possibility of separately identifying individual aberrations of the Seidel type from the Zernike aberration polynomials used in the analysis of lens interferograms. (Copyright (c) Crown Copyright 1984.)
The effect of abberations on the resolution of x-ray holography should be estimated while the conditions for the elimination of aberrations can not be fulfilled. An analysis to wave aberrations and ray aberations in in-line x-ray holography is given. All ...
... the severity of aero-optical aberration, the implications ... body, the aero-optical induced aberrations can vary ... is small and the spherical shock surface ...
... Page 2. 07 June 2010 1 Misalignment-Induced Aberrations of JWST: ... 07 June 2010 12 FFD Analysis Misalignment Coma Decentered Component ...
... in a group of nine radiologists are presented. Chromosome aberrations were detected by fluorescence plus Giemsa staining and ... consider the underlying mechanisms of aberration formation. A chromosome ab...
NBII National Biological Information Infrastructure
It is presented a quite simple procedure for measuring the astigmatism aberration of lenses by using an optometric and ophthalmic instrument, the retinoscope, as a focimeter.
NASA Astrophysics Data System (ADS)
Factors that could influence the chromosomal aberration frequency observed at first cleavage following in vivo exposure of germ cells to chemical mutagens are discussed. The techniques of chromosome aberration analysis following sperm DNA condensation by ...
samples exposed to 200 MeV/nucleon Fe ions, chromosome aberrations were analyzed ... Energetic heavy ions of high-LET induce chromosome aberrations that are ...
NASA Website
The application of ray deviation calculations based on aberration coefficients for a single optical surface for the design of beamline optical systems is reviewed. A systematic development is presented which allows insight into which aberration may be cau...
Higher-order aberrations correction can improve visual performance of human eye to some extent. To evaluate how much visual benefit can be obtained with higher-order aberrations correction we developed an adaptive optics vision simulator (AOVS). Dynamic real time optimized modal compensation was used to implement various customized higher-order ocular ...
... CONTROL, COMPUTATIONS, RATES, OPTICAL IMAGES, TOLERANCE, DIFFRACTION ANALYSIS, FOURIER ANALYSIS, GREAT BRITAIN. ...
The authors demonstrate that confocal imaging trajectories can be established in a transmission electron microscope fitted with two spherical aberration correctors. An atomic-scale electron beam, focused by aberration-corrected illumination optics, is directly imaged by a second aberration-corrected system. The initial experiment ...
Energy Citations Database
Misalignment-induced wave aberrations up to the fifth order inclusive are investigated within the framework of the Seidel eikonal theory in the approximation of the first order of misalignment shifts of optical components. An expression for the angular characteristic (angular eikonal) of a one-parameter aspherical optical surface is derived. The expression is used to write ...
The following topics are discussed: automation of chromosome analysis; storage of fixed cells from cultures of lymphocytes obtained routinely during periodic employee medical examinations; analysis of banded chromosomes; identification of first division metaphases; sister chromatid exchange; and patterns of aberration induction. (HLW)
DOE Information Bridge
A geometrical-optical analysis is developed to predict the reflex observed in retinoscopy. The analysis can be expanded to explain the reflex for an eye with aberrations. The succession of reflexes across the pupil for each position of the retinoscope is represented in a contour plot. The plots demonstrate that retinoscopy can be ...
The analysis models of Zernike aberrations of precision conformal aspheric optical windows are built, and the influences on Zernike aberrations of different aspheric optical window shapes and the variation laws of Zernike aberrations of precision conformal optical windows at different gimbal angles are analyzed ...
Chromosome aberrations in human peripheral blood are recognized parameters of cellular damage and are used as indicators of exposure to ionizing radiation and certain chemicals. However, significant interlaboratory variability exists in the results reported from different laboratories. The primary objective of the present study was to examine problems associated with the ...
PubMed Central
Numerical values are shown for the aberrations that are present in holograms which may be constructed and reconstructed from a plane wave or point source. This study centers on four types of hologram geometries: in-line, off-axis, near-image plane, and lensless-fourier transform. The aberrations illustrated in this paper have been caused by a spatial ...
The research reveals that there are higher-order aberrations in visual optical systems, and the important factors are higher-order aberrations that affect the quality of vision to further improve. To correct the higher-order aberrations, the aberrations of vision system must be effectively measured and analyzed. It ...
... of test samples to the laboratory; 5. Preparation of samples for analysis; 6. The scoring procedure for unstable chromosome aberrations used for ...
... PROSTATE CANCER, UNITED STATES, GENES, RETINOIC ACIDS, CANCER SCREENING, SULFITES, STATISTICAL ANALYSIS, MORTALITY ...
... CANCER, EPITHELIUM, NEOPLASMS, VECTOR ANALYSIS, GENES, CELLS(BIOLOGY), LESIONS, TETRACYCLINES, PITUITARY HORMONES. ...
In this paper I discuss several theoretical and practical aspects related to measuring and correcting the chromatic and spherical aberrations of a cathode objective lens as used in Low Energy Electron Microscopy (LEEM) and Photo Electron Emission Microscopy (PEEM) experiments. Special attention is paid to the various components of the cathode objective lens as they contribute ...
The quantitative analysis of the effect of aberrations in human eye on vision has important clinical value in the correction of aberrations. The wave-front aberrations of human eyes were measured with the Hartmann-Shack wave-front sensor and modulation transfer function (MTF) was computed from the wave-front ...
Technical support is provided for the operation of an emergency vehicle of Instituto de Radioprotecao e Dosimetria/Comissao Nacional de Energia Nuclear, Rio de Janeiro, Brazil, in the event of uncontrolled release of radioactivity from the Angra Nuclear P...
A radiometric calibration system constructed at the Instituto de Radioprotecao e Dosimetria (IRD) of the Brazilian Nuclear Energy Commission (CNEN) to be used by geophysicists interested in uranium exploration and scientists working with natural radioacti...
The design and construction of a double-hexapole aberration corrector has made it possible to build the prototype of a spherical-aberration corrected transmission electron microscope dedicated to high-resolution imaging on the atomic scale. The corrected instrument, a Philips CM200 FEG ST, has an information limit of better than 0.13 nm, and the spherical ...
Ocular monochromatic aberrations display dynamic behavior even when the eye is fixating on a stationary stimulus. The fluctuations are commonly characterized in the frequency domain using the power spectrum obtained via the Fourier transform. In this paper we used a wavelet-based multifractal analytical approach to provide a more in depth analysis of the ...
Sensitivity theory divides the causes of challenging behavior into three categories, aberrant contingencies, aberrant environments, and aberrant motivation. This paper replies to criticism that sensitivity theory is circular and unsupported by empirical evidence by reporting on studies that support the theory and rejecting the idea ...
ERIC Educational Resources Information Center
The regression analysis for the general image-quality equation (GIQE) [Appl. Opt. 36, 8322-8328 (1997)] was performed using image data from well-corrected optical systems. We conducted human-subject experiments to examine the use of the GIQE with aberrated imagery. A modified image-quality equation for aberrated imagery is presented ...
The aberrations of a periodic achromat are analyzed using the map of a single periodic cell. An action-angle analysis of the Lie operators describing a cell is used to illustrate the differences amongst various phase advances per cell. 6 refs., 4 tabs.
The classical and relativistic explanations of the stellar aberration are compared, on the basis of the physical models implied by the two interpretations. Our analysis shows that the physical model required by the Special Relativity theory is inconsistent with the observed effect.
High average power operation of the Mercury Laser induces dynamic aberrations to the laser beam wavefront. Analysis of recent data indicates that up to 4 waves of low order aberration (mainly focus error or power, with spatial resolution
... RESULTS Group data on age, radiation doses and chromosome aberration frequencies are presented in Table 1. Comparisons with ... the main, failed to demonstrate an increase in chromosome aberrations associ...
Among various biological dosimetry techniques, dicentric chromosome aberration method appears to be the method of choice in analysing accidental radiation exposure in most of the laboratories. The major advantage of this method is its sensitivity as the n...
Refractive surgery corrects lower-order refractive aberrations (sphere and astigmatism), but in many cases it inadvertently creates large higher-order aberrations that can degrade vision. This has prompted the development of new instruments, aberrometers,...
Approximate expressions of the ray aberrations for off-axis collimated beams and free form phase plates with a small derivative magnitude are derived with the defocus aberration taken into account. The cubic phase plate, which is one of the most commonly used phase plates in wavefront coding imaging systems, is illustrated as an example. The approximate ...
: The performance characteristics of electron microscopes and probe-forming instruments depend ultimately on the focal properties and aberrations of electron lenses. A practical method of experimentally determining the properties of electron lenses is described. The method utilizes shadows cast by two meshes inserted separately in front of the lens and behind the lens to study ...
Even the best optical microscopes available on the market exhibit chromatic aberrations to some extent. In some types of study, chromatic aberrations of current optics cannot be neglected and a software correction is highly desirable. This paper describes a novel method of chromatic aberration measurement and software correction using ...
The radiation accident in focus here occurred in a section of Goi�nia (Brazil) where more than a hundred individuals were contaminated with 137Cesium on September 1987. In order to estimate the absorbed radiation doses, initial frequencies of dicentrics and rings were determined in 129 victims [A.T. Ramalho, PhD Thesis, Subsidios a tecnica de dosimetria citogenetica gerados ...
By analysis of the dependence of longitudinal spherical aberration on the numerical aperture, it is possible to find such values of the numerical aperture, where spherical aberration is zero. Such values of the numerical aperture are called correction zones. The work theoretically analyses the described problem and equations are given ...
The aberrations of hyperbolic diffraction gratings produced with two spherical waves are analyzed theoretically and experimentally. The behavior of these gratings in collimated illumination indicates that for a grating of a given size there is a critical spatial frequency above which the aberration remains constant for all spatial frequencies. ...
Factors that could influence the chromosomal aberration frequency observed at first cleavage following in vivo exposure of germ cells to chemical mutagens are discussed. The techniques of chromosome aberration analysis following sperm DNA condensation by in vitro fertilization or fusion seem to be viable research areas for providing ...
59 intercellular distributions of chemically induced and spontaneous chromatid aberrations were analyzed for goodness of fit in respect of the Poisson (PD), the geometrical (GD), and the negative binomial distributions (NBD). The data are excellently described by the NBD. This distribution can be deduced from a model out of the queueing theory and is based on the hypothesis of ...
A numerical analysis of a four-electrode electrostatic mirror is presented. The results indicate that this mirror provides correct aberrations as a corrector for electron optical systems and unlike all other mirror configurations known to date, this new system shows for the first time that an adjustable mirror, both in magnitude of the ...
The application of ray deviation calculations based on aberration coefficients for a single optical surface for the design of beamline optical systems is reviewed. A systematic development is presented which allows insight into which aberration may be causing the rays to deviate from perfect focus. A new development allowing analytical calculation of line ...
Peripheral lymphocytes were exposed to 4 Gy X-rays and aberrations were analysed in human chromosome 5 using high-resolution multicolour banding fluorescence in-situ hybridization (mBAND). This method is suited to detect simple and complex aberrations including peri- and paracentric inversions and exchanges between both chromosomes 5. Additionally, ...
An optical analysis is developed to separate forward light scatter of the human eye from the conventional wavefront aberrations in a double pass optical system. To quantify the separate contributions made by these micro- and macro-aberrations, respectively, to the spot image blur in the Shark-Hartmann aberrometer, we develop a metric ...
In clinical ophthalmology, the wavefront aberration of human eyes is expressed by Zernike polynomial after cataract surgery and intraocular lens implantation, the human eyes aberration will change. The problem of objective evaluation of wavefront aberration introduced by the Intra-ocular (IOL) in-vivo remains unsolved. This paper ...
The cytological analysis of chromosome aberrations induced at diplotene, mid-pachytene, zygotene and leptotene stages following X-irradiation was performed at diakinesis-metaphase I in mouse spermatocytes. The dose-response relationships fitted well to linear equations for deletion-type aberrations at each stage, and to ...
The effect of intracavity aberrated perturbation on output mode structure properties of passive confocal unstable resonator is been experimentally researched by adopting Hartmann-Shack wavefront sensor and Zernike modal wavefront reconstruction on the basis of numerical simulation. Results show that intracavity perturbation such as mirror tilt and misadjustment in the vertical ...
Presented here is a characterization of aberration in medical ultrasound imaging. The characterization is optimal in the sense of maximizing the expected energy in a modified beamformer output of the received acoustic backscatter. Aberration correction based on this characterization takes the form of an aberration correction filter. ...
The Instituto de Radioprotecao e Dosimetria, IRD/CNEN, started in 1980 a program called 'PATIENT EXPOSURES IN ORAL RADIOLOGY'. The basic goal is the reduction of patient exposure during dental X-ray examinations. The program is being applied by mail to th...
The laboratory guide used by Department ofPersonnel Dosimetry of IRD/Brazilian CNEN (Instituto de Radioprotecao e Dosimetria) for in vitro and in-vivo bioassays, is presented. In vitro bioassays include fluorimetric determination of uranium in urine; alph...
After finding often how difficult it is to establish the principal notions of dosimetry, the authors decided to improve these notes prepared for the lectures, coordinating them and broadening them into a volume of interest to all approaching this discipli...
The interactions between alignment and focusing strategies and heliostat errors are described and illustrated. Some descriptions of astigmatic aberrations are developed and are used to suggest an evaluation criterion for concentrators. Finally, an analysi...
by spherical aberration. Police, action, analysis Decisions made by the police can impact positively the Universities of Liverpool and Lancaster, the Health Protection Agency and the Veterinary Laboratories Agency
E-print Network
... Abstract : Apoptosis, a cell-suicide process required for normal brain development, can also be aberrantly triggered in certain neurodegenerative ...
Analysis indicates that significant spherical aberrations can occur with a five degrees change in temperature of a plastic lens. ...
... CpG island methylation status and mutation analysis of the RB 1 gene essential ... B samples from cervical cancer (6 of 12) and liver cancer (1 of 2) S ...
... 2) a panel of markers consisting of three genes, Cyclin D2, Twist and retinoic acid receptor beta 2 (RAR beta 2), which are aberrantly ...
Painting analysis of chromosome aberrations induced by energetic heavy ions in human cells. Honglu Wu, Megumi Hada and Francis Cucinotta ...
... F. Dicello. Analysis of Mir-18 results for physical and biological dosimetry: ... chromosome damage in astronauts' lymphocytes. Int. J. Radiat. Biol 70: ... ...
optic utilizing total internal reflectance to improve flux uniformity, compensate misalignment, reduce chromatic aberration, and compensate focusing errors. Figure 1:...
National Renewable Energy Laboratory (NREL)
... and A. O. Langlois. Chromosome aberrations in irradiated ankylosing spondylitis patients. In Mutagen-Induced Chromosome Damage in Man ( ... ...
... minimize aberrations. g We selected a Melles-Griot f = -80 mm plano-convex cylindrical lens. The lens was 60 mm wide by 31 mm long. ...
0. Introduction. Adaptive optics systems are based on sampling the wavefront entering the telescope pupil, and then quickly restoring the aberrated wave to ...
Mar 1, 2011 ... By discovering external and remote influences that would be ... Analysis of Chromosomal Aberrations after Low and High Dose Rate Gamma ...
