Life Sciences Commons^™

Identification And Characterization Of Zinc-Responsive Genes In Pseudomonas Fluorescens, Thomas L. Wilson

Masters Theses

Genes responsive to elevated concentrations of zinc were identified via transposon mutagenesis in the common soil bacterium, Pseudomonas fluorescens ATCC13525. Some of these genes were essential to maintain metal homeostasis in the bacterial cell. DNA sequences of the transposon-tagged genes were determined by DNA sequencing of arbitrary PCR products. DNA sequence analysis indicated that one gene was similar to P-type ATPases responsible for transporting metal ions out of the cell. The corresponding mutant was sensitive to zinc, cadmium, and lead indicating that this gene may be responsible for defending Pseudomonas fluorescens against these metal ions. Four zinc-induced genes shared similarity …

Role Of Dopamine D4 Receptor In The Genomic And Behavioral Effects Of Psychostimulants: Relevance To Schizophrenia, Bina Garimella

Masters Theses

The role of dopamine D4 receptors in the induction and expression of behavioral sensitization to amphetamine, cocaine and PCP was investigated in this study. Behavioral changes and genomic responses accompanying sensitization were examined using a highly selective D4 receptor antagonist, PNU-101387G. Induction and expression of behavioral sensitization to cocaine was blocked by PNU-101387G. However, the D4 antagonist did not modulate the induction and expression of behavioral sensitization to PCP. Neuroadaptive genomic responses accompanying acute and chronic effects of amphetamine and their modulation by PNU-101387G was examined by looking at alterations in the expression of two immediate-early genes: c-fos and NGFI-A. …

The Influence Of Base Sheet Sizing On The Print Quality Of Matte Coated Ink Jet Papers, Saurabh K. Halwawala

Masters Theses

The most recent developments in ink-jet papers have been related to coating aμd pigment technology. Silica is the preferred pigment for matte coated ink-jet papers. Besides being expensive, the high surface area and porosity of this pigment limits the percentage coating solids to less than 30-35%, which increases production cost due to higher dryer loads. Thus, a need exists to develop a new generation of pigments. The objective of this research was to evaluate the effect of base sheet absorbency on the surface, as well as print properties of matte coated ink-jet papers using a new pigment capable of being …

Cadmium Induced Gene Expression And Signal Transduction Pathway, Daisuke Maki

Masters Theses

Cells respond to cadmium (Cd), a common environmental contaminate, by potentially decreasing reduced intracellular glutathione, as well as, increasing the expression of several antioxidant genes. One of these antioxidant genes, glucose-6- phosphate dehydrogenase (G6PDH), is the rate limiting enzyme of the pentose phosphate pathway. This pathway produces NADPH which is used for maintenance of reduced glutathione so, it is hypothesized that Cd should increase G6PDH expression. In this study, we demonstrate that Cd increases the level of G6PDH mRNA in primary rat hepatocytes in culture. In the presence of the antioxidants, N-acetylcysteine (NAC), Trolox, or glutathione monoethyl ester an attenuation …

Effect Of Size Level And Fiber Coarseness On Ink-Jet Printability Of Size Press Coated Paper, Falguni Mehta

Masters Theses

In recent years, matte coated paper has enjoyed wide spread usage for ink-jet applications. The coating performance is strongly influenced by base sheet properties including fiber coarseness and base sheet absorbency. Base sheet absorbency, which is elevated in terms of internal sizing, is a crucial property of ink-jet paper.

The objective of this research was to evaluate the influence of size level and fiber coarseness on ink-jet print qualities. A secondary objective was to examine the size reversion phenomena and to quantify the effect of size level, pigmented coating, and fiber coarseness on size reversion.

The results showed that the …

The Role Of Nf-Кb Activation In Breast Carcinoma And Glioblastoma Cell Lines, Kelly T. Murphy

Masters Theses

The nuclear factor-КB (NF-КB)/Rel family of inducible dimeric transcription factors regulates numerous genes associated with the immune, mitogenic, and apoptotic responses. Investigations were made into the role of NF-КB in breast carcinoma (MCF-7, T47D, MDA-MB-231) and glioblastoma (U87MG, U373MG, Ul 18MG) cell lines. NF-КB binding to DNA was quantified using both gel mobility shift assays and transient transfections of a vector containing a luciferase gene under the control of 4 tandem copies of the NF-КB binding sequence. To determine the correlation between NF-КB activation, cellular proliferation, and foci formation, the tumor cells were cultured and analyzed in the presence of …

Development Of A Photoinitiator Blend For Uv Cured Inks And Coatings, Madhu Bansal

Masters Theses

The purpose of this study is to develop a new standard blend of photoinitiators, having properties of low odor, high solubility, faster curing, and being efficient for pigmented as well as for clear systems. In the process, we expect to understand the behavior of mixtures of photoinitiators and their resulting UV spectra. An important first step is to prepare different blend with different photoinitiator and characterize them on cure basis. Curing properties were studied by the KMnO₄ yellow stain density test. The absorption range in the UV spectra was measured for each Photoinitiator with methanol and acrylate as background …

Isolation And Characterization Of A Genetic Locus That Confers Tolerance To Cadmium And Zinc In Pseudomonas Fluorescens, Szi Fei Feng

Masters Theses

This thesis describes the isolation and characterization of a region containing several genes involved in metal tolerance in the common soil bacterium, Pseudomonas fluorescens ATCC 13525. The DNA region was identified in a cadmium and zinc sensitive mutant, 45-B10, which contains a lacZ-based reporter gene transposon Tn5-B20 inserted in the chromosome. The DNA surrounding the transposon was cloned from this mutant strain and DNA sequencing of this region revealed seven genes that share similarity with genes whose products are involved in the cation-proton antiporter efflux system of other Gram-negative bacteria. Complete DNA sequence was obtained from four of these …

Effects Of Elevated Carbon Dioxide And Nitrogen Fixation On A Legume-Based System: A Test With Soybean And The Soybean Looper, Pseudoplusia Includens, Angela M. Spickard

Masters Theses

Wild-type and non-nodulated soybean were grown at 367 ± 10 ppm [ambient] and 756 ± 10 ppm [elevated] CO₂ to determine whether nitrogen fixation could minimize the effects of elevated CO₂ on plant nutritional and defensive chemistry. Relative to non-nodulated soybean, wild-type soybean had higher concentrations of leaf nitrogen and proteinase inhibitors, as well as lower C:N ratios and lower phenolics. Elevated CO₂ resulted in decreased leaf nitrogen and proteinase inhibitor contents, and increased C:N ratios and phenolics in both soybean strains. Constitutive levels of phenolics and proteinase inhibitors occurred as predicted by the Carbon/Nutrient Balance hypothesis …

An Investigation Into The Influence Of Common Fillers On Color Reversion Of Bctmp Pulp, Joseph N. Mikowski

Masters Theses

Recent advances in the pulping and bleaching of high-yield pulps, particularly bleached thermomechanical pulp, have made these pulps suitable replacements for bleached kraft pulps. Unfortunately, these high-yield pulps are not appropriate for making high-grade papers because of their tendency to yellow. Extensive efforts have been made to reduce the yellowing, but none of the methods that have been investigated have been at once both practical and economical.

This study investigated the ability of common pigments used in the paper industry to reduce the extent of yellowing of an 80/20 blend of bleached chemithermomechanical and bleached softwood kraft pulp. The effectiveness …

Target-And Stage-Dependent Influences On Axonal Outgrowth Of An Identified Motorneuron In Leech Cns Explants, April Crowley

Masters Theses

The neural circuit that controls rhythmic contraction of the hearts in the medicinal leech, Hirudo medicinalis, provides an amenable model to investigate pathfinding and target selection. The bilaterally paired heart tubes (HT) in leech are eventually innervated by the heart excitor motomeuron (HE) following a period of remodeling that requires the presence of the HT. To begin characterizing possible HT-derived cues, co-cultures of CNS with innervated HT have been used. Previous work demonstrated that young, but not adult, HT was able to support profuse general outgrowth, but the HE extended few projections onto HT of any age. Current studies …

Borax As Internal Stock Additive In Papermaking, Nejib S. Yousef

Masters Theses

The effect of borax on strength property of paper has been investigated in different ways. The use of borax either improved the physical properties or assisted in the reduction of refining energy to significant level.

The study of borax in the presence of precipitated and ground calcium carbonate was accomplished by using white water recycling. In the absence of retention aids, recycling of white was a necessary condition for the retention of ash content. As the ash content increased the strength property decreased. But the presence of borax slowed down the detrimental effect of fillers.

Sizing development progressively improved especially …