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Cytometry of mammalian sperm

Description: Male germ cells respond dramatically to a variety of insults and are important reproductive dosimeters. Semen analyses are very useful in studies on the effects of drugs, chemicals, and environmental hazards on testicular function, male fertility and heritable germinal mutations. The accessibility of male cells makes them well suited for analytical cytology. We might automate the process of determining sperm morphology but should not do so solely for increased speed. Rather, richer tangible ben… more
Date: October 11, 1983
Creator: Gledhill, B.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Heterogeneous processes at the intersection of chemistry and biology: A computational approach

Description: Heterogeneous processes hold the key to understanding many problems in biology and atmospheric science. In particular, recent experiments have shown that heterogeneous chemistry at the surface of sea-salt aerosols plays a large role in important atmospheric processes with far reaching implications towards understanding of the fate and transport of aerosolized chemical weapons (i.e. organophosphates such as sarin and VX). Unfortunately, the precise mechanistic details of the simplest surface enh… more
Date: February 11, 2008
Creator: Kuo, I W & Mundy, C J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

ELECTRON-SPIN-RESONANCE STUDIES ON PHOTO-SYNTHETIC MATERIALS

Description: A number of organisms have been examined for their ability to produce electron-spin-resonance signals at low temperatures in response to illumination. The efficiency of the response is of the order of not less than 5%, and the wavelength for maximum response is generally slightly on the longer side of the wavelength of maximum absorption, with a minimum appearing at the wavelength of maximum absorption.
Date: May 11, 1960
Creator: Sogo, Power B.; Carter, Louise A. & Calvin, Melvin.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A multiplexed reverse transcriptase PCR assay for identification of viral respiratory pathogens at point-of-care

Description: We have developed a nucleic acid-based assay that is rapid, sensitive, specific, and can be used for the simultaneous detection of 5 common human respiratory pathogens including influenza A, influenza B, parainfluenza type 1 and 3, respiratory syncytial virus, and adenovirus group B, C, and E. Typically, diagnosis on an un-extracted clinical sample can be provided in less than 3 hours, including sample collection, preparation, and processing, as well as data analysis. Such a multiplexed panel w… more
Date: April 11, 2007
Creator: Letant, S. E.; Ortiz, J. I.; Tammero, L.; Birch, J. M.; Derlet, R. W.; Cohen, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Mode-of-Action Uncertainty for Dual-Mode Carcinogens: A Bounding Approach for Naphthalene-Induced Nasal Tumors in Rats Based on PBPK and 2-Stage Stochastic Cancer Risk Models

Description: A relatively simple, quantitative approach is proposed to address a specific, important gap in the appr approach recommended by the USEPA Guidelines for Cancer Risk Assessment to oach address uncertainty in carcinogenic mode of action of certain chemicals when risk is extrapolated from bioassay data. These Guidelines recognize that some chemical carcinogens may have a site-specific mode of action (MOA) that is dual, involving mutation in addition to cell-killing induced hyperplasia. Although ge… more
Date: May 11, 2007
Creator: Bogen, K T
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Quantitative Tool for Producing DNA-Based Diagnostic Arrays

Description: The purpose of this project was to develop a precise, quantitative method to analyze oligodeoxynucleotides (ODNs) on an array to enable a systematic approach to quality control issues affecting DNA microarrays. Two types of ODN's were tested; ODN's formed by photolithography and ODN's printed onto microarrays. Initial work in Phase I, performed in conjunction with Affymetrix, Inc. who has a patent on a photolithographic in situ technique for creating DNA arrays, was very promising but did seem … more
Date: July 11, 2008
Creator: Whitaker, Tom J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Peroxotitanates for Biodelivery of Metals

Description: Metal-based drugs are largely undeveloped in pharmacology. One limiting factor is the systemic toxicity of metal-based compounds. A solid-phase, sequestratable delivery agent for local delivery of metals could reduce systemic toxicity, facilitating new drug development in this nascent area. Amorphous peroxotitanates (APT) are ion exchange materials with high affinity for several heavy metal ions, and have been proposed to deliver or sequester metal ions in biological contexts. In the current st… more
Date: February 11, 2009
Creator: Hobbs, David & Elvington, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Plant growth is influenced by glutamine synthetase-catalyzed nitrogen metabolism

Description: Ammonia assimilation has been implicated as participating in regulation of nitrogen fixation in free-living bacteria. In fact, these simple organisms utilize an integrated regulation of carbon and nitrogen metabolism; we except to observe an integration of nitrogen and carbon fixation in plants; how could these complex systems grow efficiently and compete in the ecosystem without coordinating these two crucial activities We have been investigating the role of ammonia assimilation regulating the… more
Date: June 11, 1991
Creator: Langston-Unkefer, P.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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X-Ray Holography at Lawrence Livermore National Laboratory

Description: The x-ray holography program at the Lawrence Livermore National Laboratory has two principal goals: (1) the development of x-ray diffraction techniques for DNA sequence analysis and (2) the development of x-ray laser holography for structural analysis of intact biological cells and organelles. DNA sequence analysis will be accomplished by applying x-ray diffraction techniques to determine the ensemble average of the sequence of labels along the individual elements of crystalline DNA. X-ray lase… more
Date: October 11, 1990
Creator: Trebes, J.; Annese, C.; Birdsall, D.; Brase, J.; Gray, J.; Lane, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Autonomous Pathogen Detection System FY02 Annual Progress Report

Description: The objective of this project is to design, fabricate and field demonstrate a biological agent detection and identification capability, the Autonomous Pathogen Detector System (APDS). Integrating a flow cytometer and real-time polymerase chain reaction (PCR) detector with sample collection, sample preparation and fluidics will provide a compact, autonomously operating instrument capable of simultaneously detecting multiple pathogens and/or toxins. The APDS will operate in fixed locations, conti… more
Date: November 11, 2002
Creator: Colston, B.; Brown, S.; Burris, K.; Elkin, C.; Hindson, B.; Langlois, R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Rapid Generation of a Nanocrystal-Labeled Peptide Library for Specific Identification of the Bacterium Clostrium Botulinum

Description: Several peptide libraries containing up to 2 million unique peptide ligands have been synthesized. The peptides are attached onto a 80 micron resin and the length of these peptide ligands ranges from 5 to 9 amino acid residues. Using a novel calorimetric assay, the libraries were screened for binding to the ganglioside-binding domain of Clostridium Tetanus Toxin, a structural similar analog of the Clostridium Botulinum toxin. Several binding peptide sequences were identified, in which the detai… more
Date: November 11, 2004
Creator: Tok, J B
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Reduction of U(VI) and Toxic Metals by Desulfovibrio Cytochrome C3

Description: The central objective of our proposed research was twofold: 1) to investigate the structure-function relationship of Desulfovibrio desulfuricans (now Desulfovibrio alaskensis G20) cytochrome c3 with uranium and 2) to elucidate the mechanism for uranium reduction in vitro and in vivo. Physiological analysis of a mutant of D. desulfuricans with a mutation of the gene encoding the type 1 tetraheme cytochrome c3 had demonstrated that uranium reduction was negatively impacted while sulfate reduction… more
Date: April 11, 2013
Creator: Wall, Judy D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

GENOME-ENABLED DISCOVERY OF CARBON SEQUESTRATION GENES IN POPLAR

Description: Plants utilize carbon by partitioning the reduced carbon obtained through photosynthesis into different compartments and into different chemistries within a cell and subsequently allocating such carbon to sink tissues throughout the plant. Since the phytohormones auxin and cytokinin are known to influence sink strength in tissues such as roots (Skoog & Miller 1957, Nordstrom et al. 2004), we hypothesized that altering the expression of genes that regulate auxin-mediated (e.g., AUX/IAA or ARF tr… more
Date: October 11, 2007
Creator: Davis, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Establishment of a viable population of red-cockaded woodpeckers at the Savannah River Site. Annual report, FY1992

Description: The Southeastern Forest Experiment Station (SEFES) began research on the red-cockaded woodpecker (RCW) on the Savannah River Site (SRS) in 1985 with the objective of restoring a viable population. This Project is conducted in cooperation with the Department of Energy, the Savannah River Forest Station (SRFS) and the Savannah River Ecology Laboratory. The program has consisted of two phases. The stabilization phase (1985--1987) focused on preventing the immediate extirpation of the RCW populatio… more
Date: September 11, 1992
Creator: Laves, K. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Optical Spectroscopy Approach for the Predictive Assessment of Kidney Functional Recovery Following Ischemic Injury

Description: Tissue that has undergone significant yet unknown amount of ischemic injury is frequently encountered in organ transplantation and trauma clinics. With no reliable real-time method of assessing the degree of injury incurred in tissue, surgeons generally rely on visual observation which is subjective. In this work, we investigate the use of optical spectroscopy methods as a potentially more reliable approach. Previous work by various groups was strongly suggestive that tissue autofluorescence fr… more
Date: February 11, 2010
Creator: Raman, R N; Pivetti, C D; Rubenchik, A M; Matthews, D L; Troppmann, C & Demos, S G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Final Report: A Transport Phenomena Based Approach to Probe Evolution of Weld Macro and Microstructures and A Smart Bi-directional Model of Fusion Welding

Description: In recent years, applications of numerical heat transfer and fluid flow models of fusion welding have resulted in improved understanding of both the welding processes and welded materials. They have been used to accurately calculate thermal cycles and fusion zone geometry in many cases. Here we report the following three major advancements from this project. First, we show how microstructures, grain size distribution and topology of welds of several important engineering alloys can be computed … more
Date: December 11, 2009
Creator: DebRoy, Dr. Tarasankar
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemical Evolution and the Origin of Life

Description: A discussion is presented of the elements, or at least most of the elements, that are usually thought of as required and characteristic of living materials. A continuous evolutionary process is conceived, beginning with a bare earth and leading to the random formation of more or less complex molecules from simple ones, and gradually, by the processes of random variation, autocatalysis, and selection, to more complex systems and the ordered array of desoxynucleic acid molecules which are the uni… more
Date: August 11, 1955
Creator: Calvin, Melvin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sugar Transport and Metabolism in Thermotoga

Description: The work conducted under this grant demonstrated that the hyperthermophilic bacterium Thermotoga neapolitana carries out glucose and lactose transport in a sodium-dependent manner and that energization of anaerobic cells is required to observe transport. We also demonstrated that Thermotoga maritima carries out maltose and glucose transport using periplasmic sugar binding proteins. We began defining patterns of expression of genes encoding sugar transport and catabolic functions in both T. mari… more
Date: February 11, 2003
Creator: Noll, Kenneth M. & Romano, Antonio H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Project Progress

Description: The proposed study investigates the effect of low dose and low dose rate radiation exposure (X-rays) on induced genomic instability and the adaptive response, including the molecular mechanisms for these phenomena. The proposed studies will utilize human cell lines containing a stably integrated plasmid that can be caused by certain kinds of mutational insults to recombine to express the green fluorescent proteins, GFP. The study will use this cell line with the fluorescent plasmid recombinatio… more
Date: September 11, 2006
Creator: Morgan, William F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transition Metal Donor-Peptide-Acceptor Complexes: From Intramolecular Electron Transfer Reactions to the Study of Reactive Intermediates

Description: The trans-polyproline (PII) oligomers (Figure 1) are unusually rigid peptide structures which have been extensively studied by our group for peptide mediated intramolecular electron transfer (ET) at long distances. We have previously studied ET across a series of metal ion donor (D) acceptor (A) oligoproline peptides with different distances, driving forces and reorganizational energies. The majority of these experiments involve generating the ET intermediate using pulse radiolysis methods, alt… more
Date: March 11, 2003
Creator: Isied, Stephan S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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