10,169 Matching Results

Search Results

Remote Sensing and GIS for Nonpoint Source Pollution Analysis in the City of Dallas' Western Watersheds

Description: This report describes the findings of a study conducted on the watersheds of "Lake Lewisville, Lake Ray Roberts, Lake Grapevine and the Elm Fork of the Trinity River between Lake Lewisville and Frazier Dam," which are all part of the upper Trinity drainage basin (p. 31). The study examines the potential benefit of "remote sensing and geographic information systems (GIS) for watershed management" in and around Dallas, Texas (p. i).
Date: August 1988
Creator: University of North Texas. Department of Biological Sciences.
Partner: UNT College of Arts and Sciences

Remote Sensing and GIS for Nonpoint Source Pollution Analysis in the City of Dallas' Eastern Watersheds

Description: This report describes the findings of a study conducted on the Eastern Watersheds of Lake Lavon, Lake Ray Hubbard, Lake Tawakoni, Lake Palestine and Lake Fork, which are located within the Blackland Prairie, Post Oak Savannah and Pineywoods provinces. These watersheds are among nine that provide drinking water to Dallas, Texas. The study examines the potential benefit of "remote sensing and geographic information systems (GIS) for watershed management" in these five watersheds (p. iii).
Date: June 1989
Creator: University of North Texas. Department of Biological Sciences.
Partner: UNT College of Arts and Sciences

High resolution transmission electron microscopy of melamine-formaldehyde aerogels and silica aerogels

Description: The goal of the high resolution transmission electron microscopy (HRTEM) was to image the structure of two tetramethyl orthosilicate (TMOS) and two melamine-formaldehyde (MF) aerogels at the single polymer chain level{sup 1,2}. With this level of structural resolution we hoped to interrelate each aerogel's structure with its physical properties and its method of synthesis. Conventional single-step base catalysed TMOS aerogels show strings of spheroidal particles linked together with minimal necking. The spheroidal particles range from 86--132 {Angstrom} and average 113{plus minus}10 {Angstrom} in diameter{sup 2}. In contrast the TMOS aerogels reported on here were made by a two step method. After extended silica chains are grown in solution under acidic conditions with a substoichiometric amount of water, the reaction is stopped and the methanol hydrolysed from TMOS is removed. Then base catalysis and additional water are added to cause gel formation is a nonalcoholic solvent. The MF aerogels were prepared for HRTEM by fracturing them on a stereo microscope stage with razor knife so that fractured pieces with smooth flat surfaces could be selected for platinum-carbon replication. The two silica (TMOS) aerogels were both transparent and difficult to see. These aerogels were fractured on a stereo microscope stage with tweezers. 6 refs., 4 figs.
Date: September 1, 1991
Creator: Ruben, G.C. (Dartmouth Coll., Hanover, NH (United States). Dept. of Biological Sciences)
Partner: UNT Libraries Government Documents Department

Biological Sciences for the 21st Century: Meeting the Challenges of Sustainable Development in an Era of Global Change

Description: The symposium was held 10-12 May, 2007 at the Capitol Hilton Hotel in Washington, D. C. The 30 talks explored how some of today's key biological research developments (such as biocomplexity and complex systems analysis, bioinformatics and computational biology, the expansion of molecular and genomics research, and the emergence of other comprehensive or system wide analyses, such as proteomics) contribute to sustainability science. The symposium therefore emphasized the challenges facing agriculture, human health, sustainable energy, and the maintenance of ecosystems and their services, so as to provide a focus and a suite of examples of the enormous potential contributions arising from these new developments in the biological sciences. This symposium was the first to provide a venue for exploring how the ongoing advances in the biological sciences together with new approaches for improving knowledge integration and institutional science capacity address key global challenges to sustainability. The speakers presented new research findings, and identified new approaches and needs in biological research that can be expected to have substantial impacts on sustainability science.
Date: May 12, 2007
Creator: Cracraft, Joel & O'Grady, Richard
Partner: UNT Libraries Government Documents Department

The BIOSCI electronic newsgroup network for the biological sciences. Final report, October 1, 1992--June 30, 1996

Description: This is the final report for a DOE funded project on BIOSCI Electronic Newsgroup Network for the biological sciences. A usable network for scientific discussion, major announcements, problem solving, etc. has been created.
Date: October 1, 1996
Creator: Kristofferson, D. & Mack, D.
Partner: UNT Libraries Government Documents Department

Sweetpotato Diseases

Description: Revised edition. There are two classes of sweet potato diseases, 1) field troubles (which are either root and stem diseases or leaf diseases), and 2) storage rots. Root and stem diseases include stem-rot, black-rot, foot-rot, scurf, and root-rot; and leaf disease, leaf-blight, white-rust, and leaf-spot. There are many methods of control for field diseases which are discussed. Control of the five storage rots described hinges on careful storage-house management.
Date: 1955
Creator: United States. Agricultural Research Service. Horticultural Crops Research Branch.
Partner: UNT Libraries Government Documents Department

Characterization of defective interfering RNAs associated with RNA plant viruses

Description: Our lab was the first to describe and characterize a defective interfering RNA (DI RNAs or DIs) in association with a small RNA plant virus. The features of the DIs that we discovered in infections of tomato bushy stunt virus were compatible with the properties of DIs identified in many animal virus infections. Animal virologists have generally recognized the importance of studying DIs because they are invaluable tools for identifying cis-acting sequences important in virus multiplication and because they offer the opportunity to elucidate mechanisms involved in viral persistence and disease attenuation. Hence our discovery offered a comparably valuable tool for use in plant virus studies for the first time. Since the original observation with TBSV, we discovered the second example of plant viral DI RNAs associated with turnip crinkle virus (TCV), and many other reports have now appeared characterizing DI and DI-like RNAs in other plant viral infections. We are seeking to improve our understanding of the mechanisms of DI generation and the precise nature of the RNA sequences necessary for DI replication and encapsidation. We also want to address the nature of the DI mediated symptom attenuation and interference effects in plants, and to determine the feasibility of using transgenic plants constitutively expressing DI RNAs for disease control. The progress made on each of these objectives is summarized along with the proposed experiments for the continuation period.
Date: January 1, 1993
Creator: Morris, T.J. (Nebraska Univ., Lincoln, NE (United States). School of Biological Sciences) & Jackson, A.O. (California Univ., Berkeley, CA (United States). Dept. of Plant Pathology)
Partner: UNT Libraries Government Documents Department


Description: The production of cellulases and hemicellulases was studied wi·th Trichoderrna reesei Rut-C-30. This organism produced, together with high cellulase activities, considerable amounts of xylanases and {beta}-glucosidase. Three cellulose concentrations (1, 2.5 and 5.0%) were examined to determine the maximum levels of cellulase activity obtainable in submerged culture. Temperature and pH profiling to increase viable cell mass to maximum levels and thereby enhancing fermentor productivity at the higher substrate levels is discussed. The effect of temperature, pH, Tween~80 concentration, carbon source and substrate concentration on the rates of mycelial growth and extra-cellular enzyme production are described.
Date: June 1, 1980
Creator: Tangnu, S.Kishen; Blanch, Harvey W. & Wilke, Charles R.
Partner: UNT Libraries Government Documents Department

Nanoimaging to Prevent and Treat Alzheimer’s and Parkinson’s Diseases. Scientific/Technical report

Description: This project will develop innovative approaches to characterization of the very early stages of protein aggregation that eventually can be translated to the development of early diagnostic tools and efficient treatments for Alzheimer’s, Parkinson’s and Huntington’s diseases. Funding will be used to acquire nanoimaging technology for nanoscale imaging, manipulation and analysis of biomedical materials to develop treatments that will repair disabled proteins and cure diseases that result from protein malfunction, specifically Alzheimer’s and Parkinson’s diseases. Expected outcomes include tests for early diagnosis and therapeutic treatments for these devastating neurological diseases. To elucidate the mechanisms of protein misfolding, we will establish an extensive program of experimental studies using a broad arsenal of advanced nanoscale and traditional techniques that will be integrated with molecular-scale modeling of protein misfolding and the nucleation of aggregate structures. To identify intracellular machinery or/and multicomponent complexes critically involved in protein misfolding, we will characterize interactions between targeted proteins and specific intracellular components or metabolites that impact on protein conformational pathways leading to protein misfolding accompanied by formation of toxic aggregated morphologies. To design innovative nanotechnology tools for the control of intracellular protein misfolding and aggregation processes, we will develop a predictive molecular scale model for intracellular protein misfolding and the formation of toxic aggregates. Verified through experimental studies, the objective is to establish an enabling foundation for the engineering of novel molecular diagnostics and therapeutics for various cellular pathologies.
Date: December 20, 2012
Creator: Yuri L. Lyubchenko, PhD, DSc
Partner: UNT Libraries Government Documents Department

Plasminogen activator inhibitor 1: Mechanisms of its synergistic regulation by growth factors

Description: My research is on the synergistic regulation of PAI-1 by EGF and TGF-β. The mechanism of synergistic regulation of PAI-1 by EGF and TGF-β are addressed. Methods are described for effective identification of RNA accessible sites for antisense oligodexoxynucleotides (ODNs) and siRNA. In this study effective AS-ODN sequences for both Lcn2 and Bcl2 were identified by in vitro tiled microarray studies. Our results suggest that hybridization of ODN arrays to a target mRNA under physiological conditions might be used as a rapid and reliable in vitro method to accurately identify targets on mRNA molecules for effective antisense and potential siRNA activity in vivo.
Date: December 1, 2011
Creator: Song, Xiaoling
Partner: UNT Libraries Government Documents Department

Imaging gene expression in real-time using aptamers

Description: Signal transduction pathways are usually activated by external stimuli and are transient. The downstream changes such as transcription of the activated genes are also transient. Real-time detection of promoter activity is useful for understanding changes in gene expression, especially during cell differentiation and in development. A simple and reliable method for viewing gene expression in real time is not yet available. Reporter proteins such as fluorescent proteins and luciferase allow for non-invasive detection of the products of gene expression in living cells. However, current reporter systems do not provide for real-time imaging of promoter activity in living cells. This is because of the long time period after transcription required for fluorescent protein synthesis and maturation. We have developed an RNA reporter system for imaging in real-time to detect changes in promoter activity as they occur. The RNA reporter uses strings of RNA aptamers that constitute IMAGEtags (Intracellular MultiAptamer GEnetic tags), which can be expressed from a promoter of choice. The tobramycin, neomycin and PDC RNA aptamers have been utilized for this system and expressed in yeast from the GAL1 promoter. The IMAGEtag RNA kinetics were quantified by RT-qPCR. In yeast precultured in raffinose containing media the GAL1 promoter responded faster than in yeast precultured in glucose containing media. IMAGEtag RNA has relatively short half-life (5.5 min) in yeast. For imaging, the yeast cells are incubated with their ligands that are labeled with fluorescent dyes. To increase signal to noise, ligands have been separately conjugated with the FRET (Förster resonance energy transfer) pairs, Cy3 and Cy5. With these constructs, the transcribed aptamers can be imaged after activation of the promoter by galactose. FRET was confirmed with three different approaches, which were sensitized emission, acceptor photobleaching and donor lifetime by FLIM (fluorescence lifetime imaging microscopy). Real-time transcription was measured by FLIM-FRET, which ...
Date: December 13, 2011
Creator: Shin, Il Chung
Partner: UNT Libraries Government Documents Department

Fourteenth-Sixteenth Microbial Genomics Conference-2006-2008

Description: The concept of an annual meeting on the E. coli genome was formulated at the Banbury Center Conference on the Genome of E. coli in October, 1991. The first meeting was held on September 10-14, 1992 at the University of Wisconsin, and this was followed by a yearly series of meetings, and by an expansion to include The fourteenth meeting took place September 24-28, 2006 at Lake Arrowhead, CA, the fifteenth September 16-20, 2007 at the University of Maryland, College Park, MD, and the sixteenth September 14-18, 2008 at Lake Arrowhead. The full program for the 16th meeting is attached. There have been rapid and exciting advances in microbial genomics that now make possible comparing large data sets of sequences from a wide variety of microbial genomes, and from whole microbial communities. Examining the “microbiomes”, the living microbial communities in different host organisms opens up many possibilities for understanding the landscape presented to pathogenic microorganisms. For quite some time there has been a shifting emphasis from pure sequence data to trying to understand how to use that information to solve biological problems. Towards this end new technologies are being developed and improved. Using genetics, functional genomics, and proteomics has been the recent focus of many different laboratories. A key element is the integration of different aspects of microbiology, sequencing technology, analysis techniques, and bioinformatics. The goal of these conference is to provide a regular forum for these interactions to occur. While there have been a number of genome conferences, what distinguishes the Microbial Genomics Conference is its emphasis on bringing together biology and genetics with sequencing and bioinformatics. Also, this conference is the longest continuing meeting, now established as a major regular annual meeting. In addition to its coverage of microbial genomes and biodiversity, the meetings also highlight microbial communities ...
Date: April 18, 2011
Creator: Miller, Jeffrey H
Partner: UNT Libraries Government Documents Department

Fundamental Studies of Recombinant Hydrogenases

Description: This research addressed the long term goals of understanding the assembly and organization of hydrogenase enzymes, of reducing them in size and complexity, of determining structure/function relationships, including energy conservation via charge separation across membranes, and in screening for novel H2 catalysts. A key overall goal of the proposed research was to define and characterize minimal hydrogenases that are produced in high yields and are oxygen-resistant. Remarkably, in spite of decades of research carried out on hydrogenases, it is not possible to readily manipulate or design the enzyme using molecular biology approaches since a recombinant form produced in a suitable host is not available. Such resources are essential if we are to understand what constitutes a “minimal” hydrogenase and design such catalysts with certain properties, such as resistance to oxygen, extreme stability and specificity for a given electron donor. The model system for our studies is Pyrococcus furiosus, a hyperthermophile that grows optimally at 100°C, which contains three different nickel-iron [NiFe-] containing hydrogenases. Hydrogenases I and II are cytoplasmic while the other, MBH, is an integral membrane protein that functions to both evolve H2 and pump protons. Three important breakthroughs were made during the funding period with P. furiosus soluble hydrogenase I (SHI). First, we produced an active recombinant form of SHI in E. coli by the co-expression of sixteen genes using anaerobically-induced promoters. Second, we genetically-engineered P. furiosus to overexpress SHI by an order of magnitude compared to the wild type strain. Third, we generated the first ‘minimal’ form of SHI, one that contained two rather than four subunits. This dimeric form was stable and active, and directly interacted with a pyruvate-oxidizing enzyme with any intermediate electron carrier. The research resulted in five peer-reviewed publications.
Date: January 25, 2014
Creator: Adams, Michael W
Partner: UNT Libraries Government Documents Department