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Characterization Of Mouse Prostate Tumor-Infiltrating Leukocytes, Daniel Alan Holterman Apr 2003

Characterization Of Mouse Prostate Tumor-Infiltrating Leukocytes, Daniel Alan Holterman

Theses and Dissertations in Biomedical Sciences

Prostate cancer is the most common form of non-cutaneous cancer among men in the United States and the second most common cause of cancer-related death among men with approximately 189,000 new cases diagnosed and 30,200 deaths of the disease in 2002. Prostate cancer can be a treatable disease but once it becomes metastatic there are no acceptable therapies. For this reason, immunotherapy has been attempted but the results have been disappointing. The TRAMP model was used to evaluate specific interactions between an intact murine immune system and a prostate tumor that expressed a naturally processed weak tumor antigen. Vaccination trials …


Purification And Antioxidant Activities Of Soybean Isoflavones, Qiju Wu Jan 2003

Purification And Antioxidant Activities Of Soybean Isoflavones, Qiju Wu

LSU Master's Theses

An efficient procedure was developed and used to extract and purify isoflavones from defatted soy flour. The purity of the final product reached 94%. The antioxidant activities of soybean isoflavones (genistein and daidzein purchased from Sigma Chemical Co, and a mixture of isoflavone glycosides extracted from defatted soy flour) were investigated by a cholesterol oxidation model accelerated by 2,2’-azobis(2-methylpropionamidine) dihydrochloride (AAPH). All components exhibited very high antioxidant activities in the inhibition of cholesterol oxidation. Genistein had higher inhibition to the formation of 5,6beta-epoxycholesterol (5,6b-EP) and 7-ketocholesterol (7-keto), while no significant difference was found between the antioxidant activities of daidzein and …


Perfecting The Match: The Visual Economy Of Egg Donation, Katherine M. Boulay Jan 2003

Perfecting The Match: The Visual Economy Of Egg Donation, Katherine M. Boulay

Doctoral

This thesis is a response to the absence of discussion in feminist and cultural studies of Assisted Reproductive Technology’s (ART) increasing utilisation of visuality and technology as complementary legitimating discourses. While critiques of the epistemologies and practices undergirding ART point to the fact that imaging technologies are used to reveal knowledge held in bodies, lacking in current theoretical work on ART, however, is an ethnographic engagement with how visual technologies actually produce the internal and externalscapes of these bodies, and knowledges about them. Mapping selective visual knowledges and technologies constitutive of the ART egg donation, the thesis engages with disparate …


Potential Functionality And Digestibility Of Oryzanol As Determined Using In Vitro Cell Culture Models, Chih-Chun Jean Huang Jan 2003

Potential Functionality And Digestibility Of Oryzanol As Determined Using In Vitro Cell Culture Models, Chih-Chun Jean Huang

LSU Doctoral Dissertations

A mouse lymphatic endothelial cell (SVEC4-10) model and a human intestinal cell (C2BBe1) model in vitro were developed and capable to be used to study antioxidant activity, hypocholesterolemic capability and digestibility of γ-oryzanol. The critical and vital parameters in developing these cell models were the emulsion preparation of hydrophobic compounds for cell models, the consistent management of cell culture, and the selection of cell viability detection methods compatible with the cell lines and the test substances. The results showed that, in some situations, γ-oryzanol could present a more effective antioxidant activity than α-tocopherol, in terms of reducing tert-butyl hydroperoxide promoted …


Inducible Gene Expression In Cell Cultures And In Microencapsulated Cells, Yong Yu Jun 2002

Inducible Gene Expression In Cell Cultures And In Microencapsulated Cells, Yong Yu

Loma Linda University Electronic Theses, Dissertations & Projects

The mifepristone-regulated transcriptional activation system provides a means to exogenously control gene expression in transformed mammalian cells in a temporal and spatial fashion. Such a promoter activation system consists of three components: The first of these is a steroidal inducer drug, mifepristone. This drug binds to the second component, a chimeric transcription factor complex, consisting of the mutant human progesterone receptor fused to the yeast GAL4 DNA-binding domain and the Herpes simplex virus protein VP 16 activation domain. The third component is a synthetic promoter, consisting of a series of GAL4 recognition sequences upstream of the adenovirus major late E1B …


Transcription, Editing, And Switching Of Antibody Genes, Rafael Casellas Jan 2002

Transcription, Editing, And Switching Of Antibody Genes, Rafael Casellas

Student Theses and Dissertations

B lymphocytes are the antibody producing cells of the immune system. During B cell lymphopoiesis in the bone marrow, immunoglobulin molecules are assembled from V, D, and J gene segments through a process known as V(D)J recombination. Because of its stochastic nature, V(D)J recombination is expected to create self-reactive specificities. In targeted animals carrying autoantibodies, these specificities were shown to be silenced by deletion, anergy, and receptor editing. While anergy and deletion physically eliminate the autoreactive clone, receptor editing salvages it by replacing its immunoglobulin receptor through ongoing V(D)J recombination. Once a functional non-self -reactive receptor is generated, B lymphocytes …


Environmental Factors Contributing To The Disaggregation Of A Colonial Cyanoprokaryote And Its Influence On Picoplankton Abundance Within Lake Joyce, Virginia, Lewis F. Affronti Jr., B. Thomas Duquette Jan 2002

Environmental Factors Contributing To The Disaggregation Of A Colonial Cyanoprokaryote And Its Influence On Picoplankton Abundance Within Lake Joyce, Virginia, Lewis F. Affronti Jr., B. Thomas Duquette

Virginia Journal of Science

A colonial cyanoprokaryote, Aphanocapsa holsatica and autotrophic picoplankton abundance were monitored weekly over a two year period in Lake Joyce, Virginia. Significant differences were observed in both the cyanoprokaryote and picoplankton abundance over the study period and an inverse relationship was observed between these two plankton groups. Disaggregation of colonies was shown to contribute to picoplankton populations where water temperature and precipitation input apparently trigger colony dispersion. This relationship is suggested to occur in other aquatic habitats. Results of this work and its implications for ecosystem dynamics are discussed.


Hypoxanthine Phosphoribosyl Transferase And Early Embryo Development, Michael Gerard Collins Ii Jan 2002

Hypoxanthine Phosphoribosyl Transferase And Early Embryo Development, Michael Gerard Collins Ii

LSU Doctoral Dissertations

The objectives of the first experiment were to ascertain if there were any differences between two mouse areola and adipose tissue cell lines. These cell lines differed only in the presence or absence of the hypoxanthine phosphoribosyl transferase (HPRT) gene. It was found that the cell lines were similar for all parameters. The objectives of the second experiment were to determine if the HPRT gene had an effect on the development of preimplantation mouse embryo. To test this transgenic mouse lines were created. The embryo sex and genotype ratio, the embryo diameter, and the embryo developmental patterns, using a Collin-Ryan …


Peptide Hydrolysis, Amino Acid Oxidation, And Nitrogen Uptake In Communities Seasonally Dominated By Aureococcus Anophagefferens, Margaret R. Mulholland, Christopher J. Gobler, Cindy Lee Jan 2002

Peptide Hydrolysis, Amino Acid Oxidation, And Nitrogen Uptake In Communities Seasonally Dominated By Aureococcus Anophagefferens, Margaret R. Mulholland, Christopher J. Gobler, Cindy Lee

OES Faculty Publications

Elevated levels of dissolved organic nitrogen (DON) and dissolved inorganic nitrogen (DIN) are among the factors implicated in the initiation of algal blooms. However, the degree to which phytoplankton augment their autotrophic metabolism with heterotrophic uptake of organic carbon that is associated with DON is unknown. We evaluated the relative importance of peptide hydrolysis, amino acid oxidation, and amino acid uptake over a seasonal cycle in an embayment on Long Island, New York, that had high concentrations of dissolved organic matter (DOM) and a bloom of the brown tide pelagophyte, Aureococcus anophagefferens. Amino acids were a significant component (up …


Phosphorus Dynamics In Cultures And Natural Populations Of Trichodesmium Spp, Margaret R. Mulholland, Sheri Floge, Edward J. Carpenter, Douglas G. Capone Jan 2002

Phosphorus Dynamics In Cultures And Natural Populations Of Trichodesmium Spp, Margaret R. Mulholland, Sheri Floge, Edward J. Carpenter, Douglas G. Capone

OES Faculty Publications

Trichodesmium spp. fix atmospheric N2 and so an element other than N limits production by these species in the oligotrophic ocean. Because dissolved inorganic phosphorus (DIP) is in short supply in many marine systems, it has been hypothesized that P is a growth-limiting nutrient for these species in nature. However, Trichodesmium is capable of hydrolyzing dissolved organic P (DOP) compounds and the inorganic products from hydrolysis may provide an additional source of P for growth. We investigated P dynamics and alkaline phosphatase activity in cultures and natural populations of Trichodesmium from the Atlantic Ocean and the north coast of …


The Ethics Of Sport: A Reader, Chad R. Carlson Oct 2001

The Ethics Of Sport: A Reader, Chad R. Carlson

Faculty Research and Creative Activity

No abstract provided.


The First Forty Years Of The Alternatives Approach: Refining, Reducing, And Replacing The Use Of Laboratory Animals, Martin L. Stephens, Alan M. Goldberg, Andrew N. Rowan Jan 2001

The First Forty Years Of The Alternatives Approach: Refining, Reducing, And Replacing The Use Of Laboratory Animals, Martin L. Stephens, Alan M. Goldberg, Andrew N. Rowan

State of the Animals 2001

The concept of the Three Rs— reduction, refinement, and replacement of animal use in biomedical experimentation—stems from a project launched in 1954 by a British organization, the Universities Federation for Animal Welfare (UFAW). UFAW commissioned William Russell and Rex Burch to analyze the status of humane experimental techniques involving animals. In 1959 these scientists published a book that set out the principles of the Three Rs, which came to be known as alternative methods. Initially, Russell and Burch’s book was largely ignored, but their ideas were gradually picked up by the animal protection community in the 1960s and early ’70s. …


The Annual Meeting Of The Iowa Academy Of Science April 20-21, 2001 [Program, 113th Meeting], Iowa Academy Of Science Jan 2001

The Annual Meeting Of The Iowa Academy Of Science April 20-21, 2001 [Program, 113th Meeting], Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Program Summary --- 1
General Session Speakers --- 4
Awards --- 7
Symposia Programs --- 8
Special Events --- 8
Poster Sessions --- 9
Section Programs/Special Sessions --- 9
Agricultural Sciences --- 9
Anthropology --- 10
Botany --- 11
Cellular, Molecular & Microbiology --- 15
Chemical Education --- 13
Chemistry: Inorganic, Analytical & Physical --- 16
Chemistry: Organic & Biological --- 16
Conservation --- 17, 24
Earth Science Teaching --- 13
Elementary Science Teaching --- 13
Engineering --- 12
Geology --- 17, 19
Physics --- 20
Physiology --- 20
Psychology & Linguistics --- 10
Science Teaching --- 13, 22, …


Control Of Phytoplankton Growth By Iron Supply And Irradiance In The Subantarctic Southern Ocean: Experimental Results From The Saz Project, P. W. Boyd, A. C. Crossley, G. R. Ditullio, F. B. Griffiths, D. A. Hutchins, B. Queguiner, Peter N. Sedwick, T. W. Trull Jan 2001

Control Of Phytoplankton Growth By Iron Supply And Irradiance In The Subantarctic Southern Ocean: Experimental Results From The Saz Project, P. W. Boyd, A. C. Crossley, G. R. Ditullio, F. B. Griffiths, D. A. Hutchins, B. Queguiner, Peter N. Sedwick, T. W. Trull

OES Faculty Publications

The influence of irradiance and Fe supply on phytoplankton processes was studied, north (47°S, 142°E) and south (54°S, 142°E) of the Subantarctic Front in austral autumn (March 1998). At both sites, resident cells exhibited nutrient stress (Fv/Fm 0 at 47°S and 9% I0 at 54°S because of MLDs of 40 (47°S) and 90 m (54°S), when these stations were occupied. The greater MLD at 54°S is reflected by tenfold higher cellular chlorophyll a levels in the resident phytoplankton. In the 47°S experiment, chlorophyll a levels increased to >1 μg/L-1 only in the high-Fe treatments, regardless …


Periradicular Response Of Immunodeficient Rats To Mechanical Pulpal Exposure, James E. Stich Mar 2000

Periradicular Response Of Immunodeficient Rats To Mechanical Pulpal Exposure, James E. Stich

Loma Linda University Electronic Theses, Dissertations & Projects

Periradicular lesions develop as a result of the interaction between root canal irritants and the immune system. The purpose of this study was to investigate the periradicular response of immunodeficient rats to their oral flora. Twenty Sprague-Dawley rats received a total body irradiation dose of 750 cGy one week prior to the investigation. The pulps of the mandibular first molars of these animals and six nonirradiated rats were exposed mechanically with a ½ round bur and left open to the oral cavity. Additional irradiation (350 cGy) was administered bi-weekly to maintain immunosuppression. Periradicular specimens were obtained after two and four …


Western Australia Soil Acidity Research And Development Update 2000 : Time To Lime, Department Of Agriculture And Food, Western Australia Jan 2000

Western Australia Soil Acidity Research And Development Update 2000 : Time To Lime, Department Of Agriculture And Food, Western Australia

Bulletins 4000 -

We have come a long way over the past three or four years in terms of both, the level of understanding and recognition of Soil Acidity as a major land degradation issue for the wheatbelt of Western Australia, and, in our actions to treat the problem.

During 1999 there were three very significant changes relating to acid soils in Western Australia.

  • Lime use in WA increased by over 200,000 tonnes from 1998 to 1999 to a record 653,000 tonnes, which was double the amount applied in 1997.
  • The Agricultural Lime Industry adopted a voluntary Lime Industry Code of Practice in …


A Scanning Electron Microscopic Study Of The Infection Of Water Oak (Quercus Nigra) By Taphrina Caerulescens, Josephine Taylor, Dale O. Birdwell Jan 2000

A Scanning Electron Microscopic Study Of The Infection Of Water Oak (Quercus Nigra) By Taphrina Caerulescens, Josephine Taylor, Dale O. Birdwell

Faculty Publications

The fungal pathogen Taphrina caerulescens was isolated from leaves of water oak (Quercus nigra) exhibiting symptoms of oak leaf blister. Healthy leaves were inoculated with a suspension of cells from pure culture in order to examine the infection process. Scanning electron microscopy was used to monitor budding of T. caerulescens cells, formation of germ tubes, and indirect penetration of leaf tissue through stomata, which occurred within 48 h post-inoculation. Direct penetration was not observed.


Evidence For Microbial Fe(Iii) Reduction In Anoxic, Mining-Impacted Lake Sediments (Lake Coeur D’Alene, Idaho), David E. Cummings, Anthony W. March, Benjamin Bostick, Stefan Spring, Frank Caccavo Jr., Scott Fendorf, Frank Rosenzweig Jan 2000

Evidence For Microbial Fe(Iii) Reduction In Anoxic, Mining-Impacted Lake Sediments (Lake Coeur D’Alene, Idaho), David E. Cummings, Anthony W. March, Benjamin Bostick, Stefan Spring, Frank Caccavo Jr., Scott Fendorf, Frank Rosenzweig

Biological Sciences Faculty Publications

Mining-impacted sediments of Lake Coeur d'Alene, Idaho, contain more than 10% metals on a dry weight basis, approximately 80% of which is iron. Since iron (hydr)oxides adsorb toxic, ore-associated elements, such as arsenic, iron (hydr)oxide reduction may in part control the mobility and bioavailability of these elements. Geochemical and microbiological data were collected to examine the ecological role of dissimilatory Fe(III)-reducing bacteria in this habitat. The concentration of mild-acid-extractable Fe(II) increased with sediment depth up to 50 g kg−1, suggesting that iron reduction has occurred recently. The maximum concentrations of dissolved Fe(II) in interstitial water (41 mg liter …


Review Of Searching For Hawa's Secret, John Stephen Brantley Jan 2000

Review Of Searching For Hawa's Secret, John Stephen Brantley

Faculty & Staff Research & Creative Activity

No abstract provided.


Phylogeny Of Calostoma, The Gelatinous-Stalked Puffball, Based On Nuclear And Mitochondrial Ribosomal Dna Sequences, Brandi D. Hughey, Gerard C. Adams, Tom D. Bruns, David S. Hibbett Jan 2000

Phylogeny Of Calostoma, The Gelatinous-Stalked Puffball, Based On Nuclear And Mitochondrial Ribosomal Dna Sequences, Brandi D. Hughey, Gerard C. Adams, Tom D. Bruns, David S. Hibbett

Department of Plant Pathology: Faculty Publications

Nucleotide sequence of the nuclear small and large subunit and the mitochondrial small and large ribosomal genes of Calostoma were used to investigate evolutionary relationships with other Basidiomycetes. In separate analyses with each gene, Calostoma was placed within the Boletales and outside the clades containing most gilled mushrooms, puffballs, stalked puffballs, earthstars, stinkhorns, and nonboletalean Gasteromycetes. This contradicted previous taxonomic hypotheses. Calostoma was most closely related to Gyroporus, Pisolithus, and Scleroderma based on maximum parsimony and maximum likelihood analysis of the mitochondrial large ribosomal gene database, which contained several representatives of most genera of the Boletales. In three …


Salinity Tolerance Of Selected Ectomycorrhizal Fungi (Pisolithus Tinctorius Pers.) And Ectomycorrhizal Eucalypts, Ben Bradshaw Jan 2000

Salinity Tolerance Of Selected Ectomycorrhizal Fungi (Pisolithus Tinctorius Pers.) And Ectomycorrhizal Eucalypts, Ben Bradshaw

Theses : Honours

Increasing soil salinity has become a major problem worldwide. It has led to a reduction in the amount of arable land, has put at risk the supply of freshwater and threatens the existence of many natural habitats. The major increase in salinity has been attributed to human activities such as clearing of natural vegetation and large-scale irrigation programmes. The alleviation of this problem has focussed on changed management strategies. the most significant of which is the re-establishment of deep rooted plants in sail affected areas. This, however, is difficult because of the variation in salt tolerance of such plants and …


Pfiesteria Piscicida And Dinoflagellates Similar To Pfiesteria, Harold G. Marshall Oct 1999

Pfiesteria Piscicida And Dinoflagellates Similar To Pfiesteria, Harold G. Marshall

Virginia Journal of Science

Pfiesteria pisiccida is a microscopic, unicellular organism that is classified as both a mixotrophic and heterotrophic dinoflagellate, which has been associated with both fish deaths and a cause of human illness (Burkholder et al., 1992; Glasgow et al., 1995; Burkholder and Glasgow, 1997). This species possesses a complex life cycle that includes motile forms (e.g. zoospores, gametes, amoebae) and a cyst stage that may remain dormant in the sediment (Burkholder et al., 1995b). Pfiesteria piscicida is known to have toxin and non-toxin producing populations, where cyst transformation into the toxic motile zoospores may be initiated by the presence of certain …


Diversity Of Microorganisms Isolated From Amber, C. L. Greenblatt, A. Davis, B. G. Clement, Christopher Kitts, T. Cox, Raul J. Cano Jul 1999

Diversity Of Microorganisms Isolated From Amber, C. L. Greenblatt, A. Davis, B. G. Clement, Christopher Kitts, T. Cox, Raul J. Cano

Biological Sciences

Claims that organisms can be cultured from amber, if substantiated, would be significant contributions to our understanding of the evolution, tenacity, and potential spread of life. Three reports on the isolation of organisms from amber have been published. Cano and Borucki recently reported the isolation of Bacillus sphaericus and Lambert et al. have described a new species designated Staphylococcus succinus from 25–40 million year old Dominican amber. These characterized organisms were phylogenetically distant from extant relatives and the Staphylococcus sp. sufficiently far removed from other extant staphylococci to be considered a new species. Here we report the culture of bacteria …


Influence Of Carbohydrate Starvation On The Culturability And Amino Acid Utilization Of Lactococcus Lactis, Mark R. Stuart May 1999

Influence Of Carbohydrate Starvation On The Culturability And Amino Acid Utilization Of Lactococcus Lactis, Mark R. Stuart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lactococci are widely used in the cheese industry as a starter culture. Starter cultures face carbohydrate starvation due to the absence of a fermentable carbohydrate in the cheese curd after pressing. Starvation leads to a decreased ability to synthesize ATP, generate a proton motive force, and accumulate nutrients necessary to maintain viability. The aim of this work was to investigate the culturability of lactococci grown with and without lactose in a chemically defined medium, and to define the metabolic changes that occur during carbohydrate starvation.

Lactose metabolism provided energy for logarithmic phase growth and greater cell density in L. lactis …


The Role Of Retinoids And Protein Kinase C In Vascular Smooth Muscle Cell Proliferation And Function, Shaoshan Wang Jan 1999

The Role Of Retinoids And Protein Kinase C In Vascular Smooth Muscle Cell Proliferation And Function, Shaoshan Wang

Theses, Dissertations and Capstones

The structural and functional changes in the arterial wall of humans and animals accompany the development of hypertension and atherosclerosis. Hence, great interest exists in the mechanisms that govern vascular smooth muscle cell contraction and proliferation. Rat aortic rings maintained in organ culture show a significant loss of contractility; whereas, vascular smooth muscle cells in culture quickly dedifferentiate into a secretory phenotype with a marked capacity for proliferation. The addition of all-trans retinoic acid (RA) and retinol to the plasma-containing medium preserved the contractile response of cultured vessels. Removal of endothelium prior to culture abolished these effects. All-trans retinoic acid …


Analysis Of Binomial Data Obtained From Plant-Tissue-Culture Studiesusing Generalized Linear Models, M. Zi̇ya Firat, Ahmet Onay Jan 1999

Analysis Of Binomial Data Obtained From Plant-Tissue-Culture Studiesusing Generalized Linear Models, M. Zi̇ya Firat, Ahmet Onay

Turkish Journal of Biology

In biology, the objective of research scientists is to gain an understanding of biological rela-tionships through experimentation. Statistical analyses are an essential part of biological research. Statistical methods used in biological research range from the very simple to the extremely complex. Consequently, caution should be taken when selecting an appropriate statistical method. Data obtained from plant-cell and tissue-culture studies can generally be placed into one of two or more groups. In other words, a dependent variable consists of placing an observation into a category. The purpose of this paper was to present statistical methods suitable for the analysis of binomial …


Isolation Of Sperm Storage Tubules From The Uterovaginal Junction Mucosa Of The Turkey, L. M. King, J. P. Brillard, M. R. Bakst, A. M. Donoghue Jan 1999

Isolation Of Sperm Storage Tubules From The Uterovaginal Junction Mucosa Of The Turkey, L. M. King, J. P. Brillard, M. R. Bakst, A. M. Donoghue

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

This study was performed to determine whether intact sperm storage tubules (SST) could be successfully isolated from the uterovaginal junction (UVJ) mucosa of the turkey. Large White BUTA hens were inseminated and euthanatized 24 to 48 h later. Oviducts were excised, UVJ tissue removed, and SST were procured by enzymatic digestion. Recovered SST were intact and contained motile sperm. The sperm were oriented with their acrosomes pointed towards the distal end of the SST, and their long axes in parallel with the long axis of the tubule’s lumen. This method for the isolation of intact SST can be readily applied …


Pfiesteria Piscicida And Dinoflagellates Similar To Pfiesteria, Harold G. Marshall Jan 1999

Pfiesteria Piscicida And Dinoflagellates Similar To Pfiesteria, Harold G. Marshall

Biological Sciences Faculty Publications

Pfiesteria pisiccida is a microscopic, unicellular organism that is classified as both a mixotrophic and heterotrophic dinoflagellate, which has been associated with both fish deaths and a cause of human illness (Burkholder et al., 1992; Glasglow et al., 1995; Burkholder and Glasgow, 1997). This species possesses a complex life cycle that includes motile forms (e.g. zoospores, gametes, amoebae) and a cyst stage that may remain dormant in the sediment (Burkholder et al, 1995b). Pfiesteria piscicida is known to have toxin and non-toxin producing populations, where cyst transformation into the toxic motile zoospores may be initiated by the presence of certain …


Multiple Duplications Of Yeast Hexose Transport Genes In Response To Selection In A Glucose-Limited Environment, Celeste J. Brown, Kristy M. Todd, R. Frank Rosenzweig Aug 1998

Multiple Duplications Of Yeast Hexose Transport Genes In Response To Selection In A Glucose-Limited Environment, Celeste J. Brown, Kristy M. Todd, R. Frank Rosenzweig

Biological Sciences Faculty Publications

When microbes evolve in a nutrient-limited environment, natural selection can be predicted to favor genetic changes that give cells greater access to limiting substrate. We analyzed a population of baker's yeast that underwent 450 generations of glucose-limited growth. Relative to the strain used as the inoculum, the predominant cell type at the end of this experiment sustains growth at significantly lower steady-state glucose concentrations and demonstrates markedly enhanced cell yield per mole glucose, significantly enhanced high-affinity glucose transport, and greater relative fitness in pairwise competition. These changes are correlated with increased levels of mRNA hybridizing to probe generated from the …


Ammonium And Nitrate Effects On Growth, Development And Nutrient Uptake Of Hydroponic Wheat, Thomas M. Hooten May 1998

Ammonium And Nitrate Effects On Growth, Development And Nutrient Uptake Of Hydroponic Wheat, Thomas M. Hooten

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The long-term effects of low and high NH4+/ NO3- uptake ratios in a system with rigorous control of pH and nitrogen concentration are poorly understood. In two replicate studies, two cultivars of wheat (Triticum aestivum) were grown to maturity with three NH4+/ NO3- ratios in hydroponic solution: 0/100, 25/75, and 85/15%. Nitrogen was controlled at ample levels throughout the 70-d life cycle and pH was controlled at 5.8 ± 0.2. An equimolar ratio of NH4+ to Cl- was used to facilitate charge balance. Nitrogen consumption …