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The Challenges of Training and Retraining Mature Learners

Description: Article discussing research on the aging process from physical, cognitive, and social and psychological perspectives, accommodations for age related changes, retraining mature learners, adaptations of the classroom environment, training technology issues, and successful corporate retraining programs to better prepare vocational educators for the workforce of the new millennium.
Date: 1998
Creator: Ennis-Cole, Demetria & Allen, Jeff M.
Partner: UNT College of Information

The Journal for Vocational Special Needs Education

Description: This issue of the Journal for Vocational Special Needs focuses on the aging process and its effects on society and the workforce. Aging is the one experience that we all have in common. Individuals are expected to live longer in the future. Many will undoubtedly work beyond the traditional retirement age. This means that the composition of workers will be a blend of people, both young and old.
Date: 1998
Creator: Allen, Jeff M.; Sarkees-Wircenski, Michelle & West, Lynda L.
Partner: UNT College of Information

Inter-American Convention on Sea Turtles : message from the President of the United States transmitting Inter-American Convention for the Protection and Conservation of Sea Turtles, with annexes, done at Caracas December 1, 1996, (The "Convention"), which was signed by the United States, subject to ratification on December 13, 1996

Description: This treaty provides the legal framework for member countries in the Americas and the Caribbean to take actions for the benefit of sea turtles
Date: 1998
Creator: United States. President (1993-2001 : Clinton) & Albright, Madeleine Korbel
Partner: UNT Libraries

Atlantic City

Description: A boardwalk with a ferris wheel and other rides juts from the right side of the canvas, a small boat grounded on the shore, a young woman building a sand castle, and scattered children play and wade at the water's edge are depicted in this oil painting.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1998
Creator: Ferguson, Max, 1959-
Partner: UNT College of Visual Arts + Design

Movie Theatre Nocturne

Description: This watercolor painting on paper depicts a cashier in his booth at the movie theater.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1998
Creator: Ferguson, Max, 1959-
Partner: UNT College of Visual Arts + Design

Dalbergia and Albizia: Plantlet Production via Tissue Culture, Karyological Evaluation, and Seed Anatomy with Scanning Electron Microscopy

Description: A publication by the National Academy of Sciences, USA (1979) outlined some of the research need for a great variety of economically important woody species whose remaining genetic resources need urgently to be collected and conserved. A viable regeneration system was established via tissue and cell suspension culture for Albizia falcataria and A. lebbeck, two important wood yielding leguminous tree species. The culture medium was standardized after several trials to obtain callus from the leaflet explants of these two tree species. The optimum use of casein hydrolysate (w/v) and coconut milk (v/v) in addition to 6-Benzylaminopurine and Indole-3-butyric acid could induce morphogenesis and somatic embryogenesis in the cultured tissue. This reports the first observation on somatic embryogenesis ofA. lebbeck using leaflets as the explants. Scanning Electron Microscopy and histological studies were done on the different stages plant development following standard techniques. Embryogenesis in suspension culture followed regeneration of plantlets in A. lebbeck. In A.falcaaria the regenerative process followed via organogenesis from the shoot buds developed on the leaf explants. After hardening the regenerated plants were transferred to the greenhouse. Some of the trees grew more than 25 feet tall within a few months outside the greenhouse. Karyotype of the three leguminous trees Albizia lebbeck, A. falcataria, and Dalbergia sissoo was analyzed. In D. sissoo, various chromosomal anomalies were observed in the cultured tissue. The abnormality indices and ploidy level varied with the age and the frequency of the subculture. In the aged culture the regenerative potential declined but was reinstated to some extent with the addition of two complex growth factors, coconut milk and casein hydrolysate. Seed anatomy of 26 species of 4 leguminous genera was studied with SEM. The main distinguishing anatomical features observed in the seed sections were uniseriate or multiseriate epidermis, epidermal projections, and number of rows ...
Date: December 1998
Creator: Ghosh, Nabarun
Partner: UNT Libraries

Biogeographic Relationships of Pocket Gophers (Geomys breviceps and Geomys bursarius) in the Southeastern Portion of Their Ranges

Description: This research utilized population genetic analyses (protein starch-gel electrophoresis and DNA sequencing of the cytochrome b mtDNA gene), host-parasite specificity (lice coevolution), remote sensing of satellite data, and geographic information systems (GIS) to characterize newly discovered populations of pocket gophers (genus: Geomys) in Arkansas. These populations are isolated and occur in seemingly unsuitable habitat in the Ozark Mountains of Arkansas. Analyses of electrophoretic and ectoparasite data suggested the populations in the Ozark Mountains represented isolates allied to Geomys bursarius, a species not known to occur in Arkansas. Comparison of mitochondrial DNA sequence data of the cytochrome b gene with that of other taxa and morphometric analyses confirmed that these populations are most closely allied to G. bursarius occurring to the north in Missouri. Moreover, these mtDNA sequence analyses indicated a degree of differentiation typical of that between other subspecies of pocket gophers. Therefore, these populations represent a distinct genetic entity in an intermediate stage of speciation and should be designated as a new subspecies, Geomys bursarius ozarkensis. Molecular clock analysis revealed a time of lineage divergence for this new subspecies as approximately 511,000 YBP. Due to the isolated nature and limited distribution of this subspecies, an evaluation of critical habitat needs was initiated. Remote sensing and GIS technologies were used to identify and describe suitable habitat Computerized classification of satellite imagery of suitable vegetation, integrated with ancillary digital information on soil associations, roads, and water systems, revealed that human activity had played a positive role in the establishment and dispersal of pocket gophers in this area. This research represents an initial combination of classical systematic tools with remote sensing and GIS to investigate biogeographic patterns and evolution. This project establishes a framework for using an interdisciplinary approach to studying organisms with limited distributions, determining evolutionary status, and providing recommendations for ...
Date: August 1998
Creator: Elrod, Douglas Allen
Partner: UNT Libraries

Role of α-Keto Acids In Cyanide Detoxification and Assimilation by Pseudomonas Bacteria

Description: Cyanide was rapidly removed when added to culture supernatants of seven different Pseudomonas. The ability to remove cyanide was correlated with the accumulation of α-keto acids (pyruvate and α-ketoglutarate). These compounds react with cyanide forming less toxic cyanohydrins, thus conferring a mechanism for bacterial cyanide tolerance. When added to growth media the α-keto acids were shown also to serve as effective cyanide antagonists. While all bacteria tested accumulated α-keto acids, only those capable of utilizing cyanide as a nutritional nitrogen source were able to metabolize cyanohydrins. In P. fluorescens NCIMB 11764, the same enzyme (cyanide oxygenase) shown previously to be involved in cyanide metabolism appears responsible for cyanohydrin transformation. Keto acid excretion is believed to represent a new mechanism of bacterial cyanide detoxification with further enzymatic metabolism of the cyanohydrins helping to explain how cyanide can satisfy the nitrogen requirement in cyanide-utilizing bacteria.
Date: December 1998
Creator: Pan, Guangliang
Partner: UNT Libraries

Development of an In Vitro Protoplast Culture System for Albizia Lebek (L.) Benth., an Economically Important Leguminous Tree

Description: An in vitro system of generating protoplasts from their callus cultures was established. The friable callus was more productive in terms of producing protoplasts than the green compact callus. The concentration of the various cell wall degrading enzymes had an effect on the viability of the protoplasts in the medium. The protoplast system developed from the experiments was stable and could be used for the transformation experiments of Albizia lebek and for other plant improvement practices.
Date: August 1998
Creator: Sinha, Debleena
Partner: UNT Libraries

Estimated Extent and Fate of Chlorinated Solvent Contamination in the Soil of the Naval Air Station, Dallas, Texas

Description: This thesis estimates the spatial extent of chlorinated solvent contamination of the soil at the Naval Air Station, Dallas, then estimates the fate and transport of these contaminants, over time, using the Soil Transport and Fate database and the Vadose-Zone Interactive Processes (VIP) modeling software. Geostatistical analysis identifies two areas with serious chlorinated solvent contamination. Fate and transport modeling estimates that this contamination will degrade and disperse from the soil phase to below regulatory limits within one year, although there is a risk of groundwater contamination. Contaminants are estimated to persist in the water and air phases of the soil. Further sampling is recommended to confirm the results of this study.
Date: August 1998
Creator: Trescott, Jill V. (Jill Virginia)
Partner: UNT Libraries

Analyses of Particulate Contaminants in Semiconductor Processing Fluids

Description: Particle contamination control is a critical issue for the semiconductor industry. In the near future, this industry will be concerned with the chemical identities of contaminant particles as small as 0.01 pm in size. Therefore, analytical techniques with both high chemical sensitivity and spatial resolution are required. Transmission electron microscopy (TEM) provides excellent spatial resolution and yields structural and compositional information. It is rarely used, however, due to the difficulty of sample preparation. The goals of this research are to promote the use of TEM as an ultrafine particle analysis tool by developing new sample preparation methods, and to exploit the new TEM techniques for analysis of particles in semiconductor processing fluids. A TEM methodology for the analysis of particulate contaminants in fluids with an elemental detectability limit as low as 0.1 part per trillion (ppt), and a particle concentration detectability limit as low as 1 particle/ml for particles greater than 0.2 pm was developed and successfully applied to the analysis of particles in HF, H202, de-ionized (DI) water, and on the surface of an electronic device. HF samples from three manufacturers were examined. For HF (B), the maximum particle concentration was 8.3 x 103 particles/ml. Both a viscous material and lath-shaped particles were observed. The Sb concentration was less than 0.6 part per billion (ppb). HF (C) was the cleanest. CaF2 and TiO2 particles were identified in HF (D). For H2 02, iron and tin oxides and hydroxides were identified. The maximum particle concentration was 990 particles/ml. The Sn and Fe concentrations were less than 0.3 ppb. Spherical and dendritic particles were observed. For DI water, spherical and dendritic particles (<2 particles/ml), and particles containing Fe or Si with concentrations less than 0.1 ppt were observed. Contaminants on an electronic device surface were also analyzed. Clusters of small particles ...
Date: August 1998
Creator: Xu, Daxue
Partner: UNT Libraries

CIMI's Z39.50 Interoperability Testbed: Search and Retrieval of Distributed Cultural Heritage Information

Description: This paper discusses the Consortium for the Computer Interchange of Museum Information (CIMI)'s international effort to provide distributed search and retrieval of cultural heritage information. A primary aspect of CIMI's work utilizes ANSI/NISO Z39.50-1995, and American National Standard protocol for information retrieval. The International Organization for Standardization (ISO) recently approved Z39.50 as ISO 23950. CIMI chose Z39.50 to enable uniform access to existing and emerging digital collections and the vast repositories of cultural heritage information resources. These resources include a variety of physical and digital objects--physical artifacts and digital derivatives of those artifacts, descriptive records designed for collection management, bibliographic records, full-text documents, online tools such as thesauri and authoritative lists of artists' names, and more. CIMI's application Z39.50 in the networked cultural heritage information environment is breaking new ground in distributed and integrated access to textual and non-textual digital collections.
Date: January 2, 1998
Creator: Moen, William E.
Partner: UNT College of Information