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open access

The Role of the Actin Cytoskeleton in Asymmetric Cell Division in Maize

Description: Stomata are specialized plant structures required for gaseous exchange with the outer environment. During stomata formation, the cytoskeleton plays an important role in controlling the division of the individual cells leading to the generation of the stomata complex. Two mutants that affect microfilament and microtubule organization in subsidiary mother cells include brk1 and dcd1. While only 20% of the subsidiary cells in the brk1 and dcd1 single mutants are abnormally shaped, it was reported… more
Date: August 2014
Creator: Alhassan, Hassan Hamdan
Item Type: Refine your search to only Thesis or Dissertation
open access

A Behavioral Model for Detection of Acute Stress in Bivalves

Description: A behavioral model for acute responses in bivalves, was developed using time series analysis for use in a real-time biomonitoring unit. Stressed bivalves closed their shell and waited for the stressful conditions to pass. Baseline data showed that group behavior of fifteen bivalves was periodic, however, individuals behaved independently. Group behavior did not change over a period of 20 minutes more than 30 percent, however, following toxic exposures the group behavior changed by more than 30 … more
Date: May 1998
Creator: Allen, H. Joel
Item Type: Refine your search to only Thesis or Dissertation
open access

Evaluation of Diet, Water, and Culture Size for Ceriodaphnia Dubia Laboratory Culturing

Description: Six reagent waters, eleven diets, and two culture sizes were evaluated for culturing C. dubia. Different filtration techniques were used to prepare the reagent waters. The eleven diets were comprised of two algae augmented with eight supplements. Reproduction and growth were assessed to discern differences among C. dubia raised in mass cultures and cultured in individual cups, during which, bacterial population densities, lipid, protein, and carbohydrate concentrations of the diets were measure… more
Date: December 1992
Creator: Allen, Jerry D. (Jerry Dee)
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of Suspended Multi-Walled Carbon Nanotubes on Daphnid Growth and Reproduction

Description: Multi-walled carbon nanotube aggregates can be suspended in the aqueous phase by natural organic matter. These aggregates are ingested by filter feeding zooplankton. Ingested aggregates result in decreased growth and decreased reproduction. These effects may be caused by reduction in energy input from normal feeding behavior. pH alters natural organic matter structure through changes in electrostatic repulsion. Altered natural organic matter structure changes multi-walled carbon nanotube aggreg… more
Date: May 2010
Creator: Alloy, Matthew Michael
Item Type: Refine your search to only Thesis or Dissertation
open access

The Generation of Recombinant Zea mays Spastin and Katanin Proteins for In Vitro Analysis

Description: Plant microtubules play essential roles in cell processes such as cell division, cell elongation, and organelle organization. Microtubules are arranged in highly dynamic and ordered arrays, but unlike animal cells, plant cells lack centrosomes. Therefore, microtubule nucleation and organization are governed by microtubule-associated proteins, including a microtubule-severing protein, katanin. Mutant analysis and in vitro characterization has shown that the highly conserved katanin is needed fo… more
Date: December 2017
Creator: Alodailah, Sattam Sonitan
Item Type: Refine your search to only Thesis or Dissertation
open access

Novel Role of Trypsin in Zebrafish

Description: It has been shown previously in our laboratory that zebrafish produce trypsin from their gills when they are under stress, and this trypsin is involved in thrombocyte activation via PAR2 during gill bleeding. In this study, I investigated another role of the trypsin that is secreted from zebrafish. This investigation has demonstrated a novel role of trypsin in zebrafish. Not only did this investigation demonstrate the role of trypsin in zebrafish behavior, but also it showed that PAR2 might be … more
Date: May 2013
Creator: Alsrhani, Abdullah Falleh
Item Type: Refine your search to only Thesis or Dissertation
open access

Hooking Mortality of Largemouth Bass Caught on Controversial Artificial Lures and Live Bait : Lake Ray Roberts, Texas

Description: A total of 192 largemouth bass were caught at Lake Ray Roberts, Texas (1995) to investigate five controversial bass angling techniques relative to hooking mortality. The bait types were Texas-rigged scented and non-scented plastic worms, Carolina-rigged scented and non-scented plastic worms, and live golden shiners. Overall hooking mortality was 21.87% and mortality was dependent upon bait type. Highest mortality resulted from the Texas-rigged scented lures, while the lowest mortality was gener… more
Date: May 1996
Creator: Alumbaugh, Andrew E. (Andrew Edward)
Item Type: Refine your search to only Thesis or Dissertation
open access

Retinoic acid Treatment Affects Kidney Development and Osmoregulatory System in the Developing Chicken (Gallus Gallus)

Description: Development is a dynamic process characterized by critical periods in which organ systems are sensitive to changes in the surrounding environment. In the current study, critical windows of embryonic growth and kidney development were assessed in the embryonic chicken. All‐trans retinoic acid (tRA) influences not only organogenesis and cell proliferation, but also targets metanephric kidney nephrogenesis. Embryonic chickens were given a single injection of tRA on embryonic day 8. tRA decre… more
Date: May 2011
Creator: Alvine, Travis Douglas
Item Type: Refine your search to only Thesis or Dissertation
open access

Isolation and Bioinformatic Characterization of Four Novel Bacteriophages from Streptomyces toxytricini

Description: Six initial phage isolates with high titer lysates were obtained using Streptomyces toxytricini B-5426 as the host bacterium. These isolates were named Goby, Toma, Yosif, Yara, Deema, and Hsoos. However, upon completion of the sequencing, it was found that the Yara and Hsoos isolates were identical, as were Goby and Deema. As a result, final analysis was completed on only the four unique isolates. All of the phages mentioned above were isolated from soil samples from different locations. Al… more
Date: May 2019
Creator: Alzaid, Hessah
Item Type: Refine your search to only Thesis or Dissertation

Quantifying the Effects of Single Nucleotide Changes in the TATA Box of the Cauliflower Mosaic Virus 35S Promoter on Gene Expression in Arabidopsis thaliana

Description: Synthetic biology is a rapidly growing field that aims to treat cellular biological networks in an analogous way to electrical circuits. However, the field of plant synthetic biology has not grown at the same pace as bacterial and yeast synthetic biology, leaving a dearth of characterized tools for the community. Due to the need for tools for the synthetic plant biologist, I have endeavored to create a library of well-characterized TATA box variants in the cauliflower mosaic virus (CaMV) 35S pr… more
Date: December 2021
Creator: Amack, Stephanie Carolina
Item Type: Refine your search to only Thesis or Dissertation

Integrating life cycle analysis and the ecological footprint calculator to foster sustainable behaviors

Description: Many tools have been developed to assess global, national or regional sustainable development policies. However, as governments develop sustainable policies, individuals must also feel empowered to affect their personal impact on the planet. This thesis integrates three sustainability concepts that lend themselves to individual sustainability: The natural step, life cycle assessment, and the ecological footprint. TNS serves to provide the meaning and substance toward sustainable development. … more
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Date: December 2002
Creator: Anderle, Kathryn
Item Type: Refine your search to only Thesis or Dissertation

Developing a Generalizable Two-Input Genetic AND Logic Gate in Arabidopsis thaliana for Multi-Signal Processing

Description: With effective engineering using synthetic biology approaches, plant-based platforms could conceivably be designed to minimize the production costs and wastes of high-value products such as medicines, biofuels, and chemical feedstocks that would otherwise be uneconomical. Additionally, modern agricultural crops could be engineered to be more productive, resilient, or restorative in different or rapidly changing environments and climates. To achieve these complex goals, information-processing ge… more
Date: December 2022
Creator: Anderson, Charles Edgar
Item Type: Refine your search to only Thesis or Dissertation
open access

The Effects of Probiotics on Growth, and Metabolism in Juvenile Oreochromis mossambicus (Mozambique Tilapia)

Description: Improving growth, lowering mortality rates, and having a faster turnaround to harvest is essential for the future of commercial aquaculture. The primary goal of this study was to determine if introducing a single strain probiotic Lactobacillus rhamnosus IMC 501 into the feed regimen of a commercially important aquaculture freshwater fish, Mozambique tilapia (Oreochromis mossambicus), would decrease mortality; change metabolic rates; and increase tissue wet mass (MW), standard length, growth rat… more
Date: May 2020
Creator: Anderson, Michael Earl
Item Type: Refine your search to only Thesis or Dissertation

Evaluation of virulence in wild type and pyrimidine auxotrophs of Pseudomonas aeruginosa using the eukaryotic model system Caenorhabditis elegans.

Description: The human opportunistic pathogen, Pseudomonas aeruginosa PAO1, has been shown to kill the nematode Caenorhabditis elegans. C. elegans has been a valuable model for the study of bacterial pathogenesis, and has reinforced the notion that common virulence and host defense mechanisms exist. Recently, the pyrimidine pathway was shown to regulate virulence levels. Therefore, mutations in the pyrimidine pathway of PAO1 showed decrease virulence in the nematode. When starving the nematode, bacterial… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: August 2004
Creator: Anvari, Sara
Item Type: Refine your search to only Thesis or Dissertation

Inquiry-based science for high school students: a forensic unit

Description: This project constitutes an instructional unit for honors biology that involves the use of science in the field of criminal investigation and forensics. Before beginning the unit, the learners should have mastered basic laboratory skills, including use of the microscope. They should also have an understanding of the basic structure and function of DNA and its role in heredity and protein synthesis. The standard time frame is 24 days with 70-minute periods, but can be easily adjusted to meet cla… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2000
Creator: Apple, Kendra Kea
Item Type: Refine your search to only Thesis or Dissertation
open access

Effector Response of the Aspartate Transcarbamoylase From Wild Type Pseudomonas Putida and a Mutant with 11 Amino Acids Deleted at the N-terminus of PyrB.

Description: Like its enteric counterpart, aspartate transcarbamoylase (ATCase) from Pseudomonas putida is a dodecamer of two different polypeptides. Unlike the enterics, the Pseudomonas ATCase lacks regulatory polypeptides but employs instead inactive dihydroorotases for an active dodecamer. Previous work showed that PyrB contains not only the active site but also the effector binding sites for ATP, UTP and CTP at its N-terminus. In this work, 11 amino acids were deleted from the N-terminus of PyrB and t… more
Date: May 2002
Creator: Asfour, Hani
Item Type: Refine your search to only Thesis or Dissertation
open access

Spatial Variations and Cultural Explanations to Obesity in Ghana

Description: While obesity is now recognized as a major health concern in Ghana, the major drivers, causal factors, and their spatial variation remain unclear. Nutritional changes and lack of physical activity are frequently blamed but the underlying factors, particularly cultural values and practices, remain understudied. Using hot spot analysis and spatial autocorrelation, this research investigates the spatial patterns of obesity in Ghana and the explanatory factors. We also use focus group discussions t… more
Date: August 2019
Creator: Asubonteng, Agnes
Item Type: Refine your search to only Thesis or Dissertation
open access

Hypoxia-Induced Cardiac Arrest Alters Central Nervous System Concentrations of the GLYT2 Glycine Transporter in Zebrafish (Danio rerio)

Description: Hypoxia as a stressor has physiological implications that have been a focal point for many physiological studies in recent years. In some studies, hypoxia had large effects on the organ tissue degeneration, which ultimately effects multiple ecological processes. These organ tissue studies played a part in the development of new fields like neurocardiology, a specialty that studied the relationship between the brain and the heart. This thesis focuses on how hypoxia-induced cardiac arrest alte… more
Date: July 2023
Creator: Auzenne, Alexis
Item Type: Refine your search to only Thesis or Dissertation
open access

Producing a Film on Oil Spill Research for the Public

Description: The Deepwater Horizon oil drilling rig exploded on April 20, 2010, off the coast of Louisiana in the Gulf of Mexico. Following the spill, British Petroleum, leaser of the rig, set up a funding institution known as the Gulf of Mexico Research Initiative (GoMRI) to support research and understanding of the spill on the environments and peoples of the gulf. This outreach project was created alongside research of the RECOVER consortium, funded by GoMRI, to communicate what is happening within resea… more
Date: December 2018
Creator: Barnes, Emma Katherine
Item Type: Refine your search to only Thesis or Dissertation
open access

Ecological Significance and Underlying Mechanisms of Body Size Differentiation in White-tailed Deer

Description: Body size varies according to nutritional availability, which is of ecological and evolutionary relevance. The purpose of this study is to test the hypothesis that differences in adult body size are realized by increasing juvenile growth rate for white-tailed deer (Odocoileus virginianus). Harvest records are used to construct growth rate estimates by empirical nonlinear curve fitting. Results are compared to those of previous models that include additional parameters. The rate of growth increa… more
Date: May 2012
Creator: Barr, Brannon
Item Type: Refine your search to only Thesis or Dissertation
open access

Comparison of Aspartate Transcarbamoylase and Pyrimidine Salvage in Sporosarcina urea, Sprolactobacillus inulinus, Lactobacillus fermentum, and Micrococcus luteus

Description: The enzyme that catalyzes the committed step in pyrimidine biosynthesis, aspartate transcarbamoylase, has been compared in selected endospore-forming organisms and in morphologically similar control organisms. The ATCases and pyrimidine salvage from Sporosarcina ureae, Sporolactobacillus inulinus, Lactobacillus fermentum, and Micrococcus luteus were compared to those of Bacillus subtilis. While the ATCases from Sporosarcina ureae, Sporolactobacillus inulinus, and L. fermentum were found to exhi… more
Date: August 1994
Creator: Barron, Vincent N. (Vincent Neal)
Item Type: Refine your search to only Thesis or Dissertation
open access

Hepatotoxicity of Mercury to Fish

Description: Tissue samples from spotted gar (Lepisosteus oculatus) and largemouth bass (Micropterus salmoides) were collected from Caddo Lake. Gar and bass livers were subjected to histological investigation and color analysis. Liver color (as abs at 400 nm) was significantly correlated with total mercury in the liver (r2 = 0.57, p = 0.02) and muscle (r2 = 0.58, p = 0.01) of gar. Evidence of liver damage as lipofuscin and discoloration was found in both species but only correlated with liver mercury con… more
Date: August 2010
Creator: Barst, Benjamin Daniel
Item Type: Refine your search to only Thesis or Dissertation
open access

Spatial and Temporal Patterns of Areal and Volumetric Phytoplankton Productivity of Lake Texoma

Description: Phytoplankton productivity of Lake Texoma was measured for one year from August 1999 to August 2000 for four stations, using the oxygen change method and laboratory incubation. Mean values of the photosynthetic parameters, PBmax and alphaB ranged from 4.86 to 46.39 mg O2.mg Chl-1.hr-1 for PBmax and 20.06 to 98.96 mg O2.mg Chl-1.E-1.m2 for alphaB. These values were in the range to be expected for a highly turbid, temperate reservoir. Estimated gross annual areal productivity ranged from 594 g… more
Date: August 2001
Creator: Baugher, Tessy
Item Type: Refine your search to only Thesis or Dissertation
open access

Evaluating Fish Impingement and Entrainment at the Comanche Peak Steam Electric Station

Description: This study was designed to determine if impingement and entrainment by cooling water intake at the Comanche Peak Steam Electric Station have an adverse impact upon the Squaw Creek Reservoir fish population. The yearly impingement of fish was estimated to be 262,994 of 14 species. The threadfin shad (Dorosoma petenense) accounted for 96% of this total. Entrainment of eggs and larvae for a five month period was estimated to be 15,989,987 and 42,448,794 respectively. Two fish population studies we… more
Date: May 1996
Creator: Bauml, George A. (George Arthur)
Item Type: Refine your search to only Thesis or Dissertation
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