Graphical Methods for Quantifying Macromolecules through Bright Field Imaging (open access)

Graphical Methods for Quantifying Macromolecules through Bright Field Imaging

Bright ?eld imaging of biological samples stained with antibodies and/or special stains provides a rapid protocol for visualizing various macromolecules. However, this method of sample staining and imaging is rarely employed for direct quantitative analysis due to variations in sample fixations, ambiguities introduced by color composition, and the limited dynamic range of imaging instruments. We demonstrate that, through the decomposition of color signals, staining can be scored on a cell-by-cell basis. We have applied our method to Flbroblasts grown from histologically normal breast tissue biopsies obtained from two distinct populations. Initially, nuclear regions are segmented through conversion of color images into gray scale, and detection of dark elliptic features. Subsequently, the strength of staining is quanti?ed by a color decomposition model that is optimized by a graph cut algorithm. In rare cases where nuclear signal is significantly altered as a result of samplepreparation, nuclear segmentation can be validated and corrected. Finally, segmented stained patterns are associated with each nuclear region following region-based tessellation. Compared to classical non-negative matrix factorization, proposed method (i) improves color decomposition, (ii) has a better noise immunity, (iii) is more invariant to initial conditions, and (iv) has a superior computing performance
Date: August 14, 2008
Creator: Chang, Hang; DeFilippis, Rosa Anna; Tlsty, Thea D. & Parvin, Bahram
Object Type: Article
System: The UNT Digital Library
A Multivariate Time Series Method for Monte Carlo Reactor Analysis (open access)

A Multivariate Time Series Method for Monte Carlo Reactor Analysis

A robust multivariate time series method has been established for the Monte Carlo calculation of neutron multiplication problems. The method is termed Coarse Mesh Projection Method (CMPM) and can be implemented using the coarse statistical bins for acquisition of nuclear fission source data. A novel aspect of CMPM is the combination of the general technical principle of projection pursuit in the signal processing discipline and the neutron multiplication eigenvalue problem in the nuclear engineering discipline. CMPM enables reactor physicists to accurately evaluate major eigenvalue separations of nuclear reactors with continuous energy Monte Carlo calculation. CMPM was incorporated in the MCNP Monte Carlo particle transport code of Los Alamos National Laboratory. The great advantage of CMPM over the traditional Fission Matrix method is demonstrated for the three space-dimensional modeling of the initial core of a pressurized water reactor.
Date: August 14, 2008
Creator: Ueki, Taro
Object Type: Report
System: The UNT Digital Library
Panofsky Agonisters: 1950 Loyalty Oath at Berkeley; Pief navigates the crisis (open access)

Panofsky Agonisters: 1950 Loyalty Oath at Berkeley; Pief navigates the crisis

In 1949-1951 the University of California was traumatized and seriously damaged by a Loyalty Oath controversy. Wolfgang K. H. Panofsky, a young and promising physics professor and researcher at Lawrence's Radiation Laboratory, was caught up in the turmoil.
Date: August 14, 2008
Creator: Jackson, John David
Object Type: Article
System: The UNT Digital Library
Zachary D. Barker: Final DHS HS-STEM Report (open access)

Zachary D. Barker: Final DHS HS-STEM Report

Working at Lawrence Livermore National Laboratory (LLNL) this summer has provided a very unique and special experience for me. I feel that the research opportunities given to me have allowed me to significantly benefit my research group, the laboratory, the Department of Homeland Security, and the Department of Energy. The researchers in the Single Particle Aerosol Mass Spectrometry (SPAMS) group were very welcoming and clearly wanted me to get the most out of my time in Livermore. I feel that my research partner, Veena Venkatachalam of MIT, and I have been extremely productive in meeting our research goals throughout this summer, and have learned much about working in research at a national laboratory such as Lawrence Livermore. I have learned much about the technical aspects of research while working at LLNL, however I have also gained important experience and insight into how research groups at national laboratories function. I believe that this internship has given me valuable knowledge and experience which will certainly help my transition to graduate study and a career in engineering. My work with Veena Venkatachalam in the SPAMS group this summer has focused on two major projects. Initially, we were tasked with an analysis of data …
Date: August 14, 2008
Creator: Barker, Z D
Object Type: Report
System: The UNT Digital Library