Results 261 to 270 of about 337,692 (304)
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Ophthalmology, 2012
We report the correlation of the neuro-ophthalmological findings with a 18 F-fluorodeoxyglucose positron emission tomography-computed tomography study ( 18 F-FDG-PET/ CT) in a pediatric patient affected by a pure right homon- ymous hemianopia manifested after minor head injury and no evidence of any lesions at other neuroimage studies, visual evoked ...
Cistaro, Angelina +9 more
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We report the correlation of the neuro-ophthalmological findings with a 18 F-fluorodeoxyglucose positron emission tomography-computed tomography study ( 18 F-FDG-PET/ CT) in a pediatric patient affected by a pure right homon- ymous hemianopia manifested after minor head injury and no evidence of any lesions at other neuroimage studies, visual evoked ...
Cistaro, Angelina +9 more
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Europhysics Letters (EPL), 1995
The first pulsed microbeam for positrons in the keV energy range is described. The principle of operation and the construction details are given. The performance achieved is: 20 μm (FWHM) spot diameter; 350 ps (FWHM) time resolution; 5000 e+ /(s mCi) at 5 keV final energy.
Zecca, Antonio +11 more
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The first pulsed microbeam for positrons in the keV energy range is described. The principle of operation and the construction details are given. The performance achieved is: 20 μm (FWHM) spot diameter; 350 ps (FWHM) time resolution; 5000 e+ /(s mCi) at 5 keV final energy.
Zecca, Antonio +11 more
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Psychiatric Clinics of North America, 1986
PET is a unique tool for the direct in vivo evaluation of physiologic processes within discrete areas of the brain. Thus far, its application to the study of schizophrenia has served to confirm the subtleties of this illness. However, PET does promise to increase our knowledge of the neurochemical anatomy of the normal and abnormal mind with respect to
R M, Cohen, W E, Semple, M, Gross
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PET is a unique tool for the direct in vivo evaluation of physiologic processes within discrete areas of the brain. Thus far, its application to the study of schizophrenia has served to confirm the subtleties of this illness. However, PET does promise to increase our knowledge of the neurochemical anatomy of the normal and abnormal mind with respect to
R M, Cohen, W E, Semple, M, Gross
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Physics in Medicine & Biology, 1970
A hybrid positron scanner, which combines the simplicity of a mechanical scanner with the increased sensitivity of a large area array, has been designed utilizing nine crystal pairs and 25 coincidence circuits. This technique has the advantage over single-pair positron systems in that greatly increased source activity may be viewed.
C A, Burnham, S, Aronow, G L, Brownell
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A hybrid positron scanner, which combines the simplicity of a mechanical scanner with the increased sensitivity of a large area array, has been designed utilizing nine crystal pairs and 25 coincidence circuits. This technique has the advantage over single-pair positron systems in that greatly increased source activity may be viewed.
C A, Burnham, S, Aronow, G L, Brownell
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Effect of the Positron-Phonon Interaction on Positron Motion
Physical Review B, 1970We have made a calculation of the effect of the positron-phonon interaction on positron motion in simple cubic metals. We use a slightly modified jellium model to treat the positron-phonon interaction, and several approximations are introduced. Still, we feel confident that our calculations are qualitatively correct, and we conclude that phonons must ...
A. Perkins, J. P. Carbotte
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Physical Review B, 1985
Positron diffusion in Si(100) and Si(111) has been studied using a variable-energy positron beam. The positron diffusion coefficient is found to be ${D}_{+}$=2.7\ifmmode\pm\else\textpm\fi{}0.3 ${\mathrm{cm}}^{2}$/sec using a Makhov-type positron implantation profile, which is demonstrated to fit the data more reliably than the more commonly applied ...
Nielsen, B. +3 more
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Positron diffusion in Si(100) and Si(111) has been studied using a variable-energy positron beam. The positron diffusion coefficient is found to be ${D}_{+}$=2.7\ifmmode\pm\else\textpm\fi{}0.3 ${\mathrm{cm}}^{2}$/sec using a Makhov-type positron implantation profile, which is demonstrated to fit the data more reliably than the more commonly applied ...
Nielsen, B. +3 more
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Mobility of positrons in polyethylene
Physical Review B, 1986We have measured the positron drift velocity versus electric field in polyethylene by observing the Doppler shift of the annihilation photons. We find that the average positron mobility computed using the internal electric field (dielectric constant =2.26) is \ensuremath{\mu}=10.3\ifmmode\pm\else\textpm\fi{}1.5 ${\mathrm{cm}}^{2}$ ${\mathrm{V ...
, Mills +3 more
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Positron Polarons and Positron Trapping by Defects in LiF
Journal of the Physical Society of Japan, 1975The momentum distribution of annihilation photon pairs in LiF observed at 293 K was found to be slightly broader than that at 89 K. Assuming that the positrons are thermalized and annihilate mainly in the polaron states, the broadening was analyzed in terms of their effective mass.
Kunio Fujiwara +3 more
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Radiation Physics and Chemistry (1977), 1984
One of the most exciting new techniques introduced in the last ten years is positron emission tomography (PET). PET provides quantitative, three-dimensional images for the study of specific biochemical and physiological processes in the human body.
Y L, Yamamoto +4 more
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One of the most exciting new techniques introduced in the last ten years is positron emission tomography (PET). PET provides quantitative, three-dimensional images for the study of specific biochemical and physiological processes in the human body.
Y L, Yamamoto +4 more
openaire +2 more sources