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Search Publications by: Zachary H. Levine (Fed)

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Displaying 76 - 100 of 267

RECIST vs. Volume Measurement in Medical CT Using Ellipsoids of Known Size

April 12, 2010
Author(s)
Zachary H. Levine, Bruce R. Borchardt, Nolan J. Brandenburg, Charles W. Clark, Balasubramanian Muralikrishnan, Craig M. Shakarji, Joseph J. Chen, Eliot L. Siegel
(a) Purpose: We wanted to test the extent to which two common methods of determining the sizes of tumors would perform when compared to a statistically significant number of well-characterized reference objects. The size of the objects was chosen to

Heralded, pure-state single-photon source based on a Potassium Titanyl Phosphate waveguide

February 15, 2010
Author(s)
Zachary H. Levine, Jingyun Fan, Jun Chen, Alexander E. Ling, Alan L. Migdall
WWe analyze the generation of single spatial mode, spectrally uncorrelated photon pairs via type II spontaneous parametric downconversion in a Potassium Titanyl Phosphate (KTP) waveguide using real experimental parameters. We show that this source can be

A Low-Cost Density Reference Phantom for Computed Tomography

January 2, 2009
Author(s)
Zachary H. Levine, Ming-Dong Li, Anthony P. Reeves, David F. Yankelevitz, Joseph J. Chen, Eliot L. Siegel, Adele P. Peskin, Diana N. Zeiger
We have characterized a commercially-available polyurethane foam which is marketed for modeling parts in the aircraft, automotive, and related industries. We find that the foam may be suitable for use as a density reference standard in the range below -700

A Low Cost Fiducial Reference for Computed Tomography

November 11, 2008
Author(s)
Zachary H. Levine, Steven Grantham, Daniel S. Sawyer, Anthony P. Reeves, David F. Yankelevitz
Rationale and Objectives. To detect the growth in lesions, it is necessary to ensure that the apparent changes in size are above the noise floor of the system. By introducing a fiducial reference, it may be possible to detect smaller changes in lesion size

Diffraction and Electron Energy Loss to Plasmons in Silicon Slabs

March 10, 2008
Author(s)
Zachary H. Levine
Dynamic diffraction patterns have been calculated for 25-nm thick slabs of silicon with [001], [111], and [110] faces for a 120 keV electron beam. The calculation used the mixed dynamical form factor in the dielectric formulation. Dielectric matrices with

Synthetic Incoherence for Electron Microscopy

July 11, 2007
Author(s)
Zachary H. Levine, Robyn M. Dunstan
Tomographic studies of submicrometer samples in materials science using electron microscopy have been inhibited by diffraction effects. In the present work, we describe two practical methods for ameliorating these effects. In one, the sample is scanned

Synthetic Incoherence Via Scanned Gaussian Beams

December 1, 2006
Author(s)
Zachary H. Levine
Tomography, in most formulations, requires an incoherent signal. For a conventional transmission electron microscope, the coherence of the beam often results in diffraction effects which limit the utility of a tilt series with conventional tomographic