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Articles 3271 - 3300 of 4351

Full-Text Articles in Life Sciences

Agronomic Growth Characteristics Of Two Varieties Of Baby Carrots (Daucus Carota L.) At Three Planting Densities In Walipini (Ingavi Province), María Eugenia Valdez Cuba Jan 2006

Agronomic Growth Characteristics Of Two Varieties Of Baby Carrots (Daucus Carota L.) At Three Planting Densities In Walipini (Ingavi Province), María Eugenia Valdez Cuba

Theses and Dissertations

Our objective is to study the agronomic growth characteristics of two varieties of baby carrots at three planting densities. The study site is in the area of Walipini, town of Lentanias, province of Ingavi, department of La Paz, Bolivia. In this investigation, the two varieties of baby carrots used were ‘Amsterdam Forcing 3-Minicor’ and ‘Thumbelina’ (Daucus carota var. sativus). Both varieties were planted at densities of 333 plants/m2, 166 plants/m2 and 111 plants/m2 with a planting interval of two days. Statistical differences were observed for the following variables: plant height, root length, root diameter, base diameter, leaf yield, and root …

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Application Of Different Levels Of Byproducts From Quinua (Chenopodium Quinoa Willd.) In The Preparation Of Rations For Guinea Pigs (Cavia Porcellus L.) In The Growing And Fattening Stages, Grover Antonio Aduviri Paredes Jan 2006

Application Of Different Levels Of Byproducts From Quinua (Chenopodium Quinoa Willd.) In The Preparation Of Rations For Guinea Pigs (Cavia Porcellus L.) In The Growing And Fattening Stages, Grover Antonio Aduviri Paredes

Theses and Dissertations

From quinua crop residue it is possible to obtain byproducts that can be used to feed small animals, especially guinea pigs. These byproducts can become an alternative feed to ameliorate food deficiencies generally present in the Altiplano. This study compared the effect of consumed quinua meal rations on guinea pig body weight increase and food and economic conversion. This project was developed in two phases: pre-experimental and experimental. In the first phase, genetic material appropriate for the project and the initial rations for consumption was acquired. The second phase included the experimental design where the treatments were developed. The study …

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Apparent Digestibility In Vicunas Fed With Soft Straw And Alfalfa In The C.E.A.C., Felisa Capriles Apaza Jan 2006

Apparent Digestibility In Vicunas Fed With Soft Straw And Alfalfa In The C.E.A.C., Felisa Capriles Apaza

Theses and Dissertations

South American camelids are a source of fiber and meat for the inhabitants of the Andean region of Bolivia, Argentina, and Chile. When camelids are well fed they efficiently convert the Andean flora into meat with high protein content. Vicuñas have a great capacity to produce wool to be used as a high quality fiber. However, the yield of vicuña meat production is generally low. There have been several studies concerning nutritional forage sources for camelids, resulting in improved nutrition, decreased morbidity and mortality, and intensified production systems. Soft straw is a source of tough forage with low protein content. …

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Metabolic Profile And Nitrogen Balance In Llamas (Lama Glama) Fed With Jipi Quinua And Barley Hay, Viacha Municipality - Department Of La Paz, Meliton Ajata Avircata Jan 2006

Metabolic Profile And Nitrogen Balance In Llamas (Lama Glama) Fed With Jipi Quinua And Barley Hay, Viacha Municipality - Department Of La Paz, Meliton Ajata Avircata

Theses and Dissertations

This research was completed in Letanías, Viacha, La Paz, Bolivia, to determine the metabolic profile in blood plasma (total protein, glucose, urea, albumin, total lipids, creatinine, triglycerides, and cholesterol concentrations), live weight gain, and Nitrogen balance in adult llamas fed with 4 rations of barley and quinoa residue. Eight adult (4-5 year old) Q’ara type llamas were used in this study. Study llamas were trained to stay in metabolic cages with feces collection harnesses. Llamas were given one of the following feed rations: ration A (20% quinoa residue, 80% barley), ration B (40% quinoa residue, 60% barley), ration C (60% …

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Effect Of The Use Of Amaranth Leaf Flour In The Development Of A Diet For Guinea Pigs, Verónica Del Rocío Guerrero Carrera Jan 2006

Effect Of The Use Of Amaranth Leaf Flour In The Development Of A Diet For Guinea Pigs, Verónica Del Rocío Guerrero Carrera

Theses and Dissertations

This study was carried out in the San Clemente community. The objective was to analyze the effect of using amaranth leaf flour in the creation of a diet for guinea pigs. The field work was done over a period of 12 months and was done in two phases: Development of the diet: this was done by growing the amaranth, cutting it, and dehydrating it until flour was obtained. Then, it was mixed into the diet in accordance with the pre-determined formula along with the other respective materials. Handling of guinea pigs: This was done in the shed of the San …

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Effect Of Chemical Fertilization And Organic Amaranth (Amaranthus Caudatus L.) Var. Alegria Iniap Chaltura, Andrade Andrade Pablo Raúl Jan 2006

Effect Of Chemical Fertilization And Organic Amaranth (Amaranthus Caudatus L.) Var. Alegria Iniap Chaltura, Andrade Andrade Pablo Raúl

Theses and Dissertations

The present investigation was made in the Experimental Farm "La Pradera", located in the province of Imbabura, the parish of San José de Chaltura, to 1350 meters above sea level and an average temperature of 16, 4⁰ C. To analyze the effect of the chemical and organic fertilization in amaranth of variety INIAP "Alegría" was the primary target of the investigation. The field work was made in a lapse of 6 months. The design of complete blocks (DBCA) with 15 treatments was used at random and three repetitions by treatment. The experimental unit was 18 m². It was evaluated by …

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Determination Of The Primary Levels Of The Residues Of The Seeds Of Wheat, Maize, And Barley For The Elaboration Of The Food Mixture For Rabbits, Aida Esperanza Morejon Jacome Jan 2006

Determination Of The Primary Levels Of The Residues Of The Seeds Of Wheat, Maize, And Barley For The Elaboration Of The Food Mixture For Rabbits, Aida Esperanza Morejon Jacome

Theses and Dissertations

The present investigation was done in the parish of Chaltura, Granja "La Pradera" which belongs to the University Técnica del Norte. The main objective of this investigation was to determine the primary levels of the residues of the seeds of wheat, maize, barley for the elaboration of the food mixture for rabbits. The evaluated variables, food consumed, weight gain, food value, protein percentage, production cost per treatment. Previously to the initiation of the field phase bromatological analysis were done on the three food mixtures in the National Institute of Farming Investigation, Quality and Nutrition Area. The treatments were four: TI …

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Energy Value In Llamas (Lama Glama) Fed With Alfalfa Hay (Modicago Sativa) And Barley (Hordeum Vulgare) For Apparent Digestibility In Vivo In The National Camelid Germplasm Bank (Ceac), Edwin Gonzalo Ugarte Huanca Jan 2006

Energy Value In Llamas (Lama Glama) Fed With Alfalfa Hay (Modicago Sativa) And Barley (Hordeum Vulgare) For Apparent Digestibility In Vivo In The National Camelid Germplasm Bank (Ceac), Edwin Gonzalo Ugarte Huanca

Theses and Dissertations

In this experiment, we used four male llamas that were three to four years of age from the Khara race. They were divided into two ad libitum feeding groups. The digestible energy (ED) was determined using samples that were sent to the laboratory. These samples were derived from a conventional in vivo assay using the method of total fecal collection in order to determine the difference between energy consumed and energy excreted. Metabolizable energy was calculated by deducting digestible energy, energy loss in the urine and energy loss in the gases (methane). Urinary energy was determined through the measurement of …

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Patterns Of Habitat Use By Bats Along A Riparian Corridor In Northern Utah, Duke S. Rogers, Mark C. Belk, Malinda W. González, Brent L. Coleman Jan 2006

Patterns Of Habitat Use By Bats Along A Riparian Corridor In Northern Utah, Duke S. Rogers, Mark C. Belk, Malinda W. González, Brent L. Coleman

Faculty Publications

We examined patterns of habitat use within a community of bats along the Provo River in Heber Valley, Utah. The landscape was divided into 5 habitat categories: riparian forest, wetland, agricultural field, edge, and a habitat restoration site. We used Anabat II bat detectors to record the number of echolocation calls per night within each habitat type as an index of bat activity. Echolocation calls were classified into foraging guilds based on acoustic traits, and we analyzed activity by entire community and by the 4 guilds related to habitat type and environmental variables. Activity was not significantly related to moon …

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Assessment Of Chenopodium Quinoa Willd. Genetic Diversity In The Usda And Cip-Fao Collections Using Ssr?S And Snp?S, Shawn A. Christensen Nov 2005

Assessment Of Chenopodium Quinoa Willd. Genetic Diversity In The Usda And Cip-Fao Collections Using Ssr?S And Snp?S, Shawn A. Christensen

Theses and Dissertations

Quinoa (Chenopodium quinoa Willd.) is a staple grain for the indigenous people of the Andean region of South America with excellent nutritional qualities, including protein content. The objective of this study is to report on the development of fluorescence-tagged simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs) to (1) genetically characterize the inherent diversity of 152 accessions of C. quinoa; (2) determine to what degree the CIP-FAO collection represents the range of genetic diversity in quinoa; and (3) test four hypotheses regarding quinoa?s center of diversity, Highland and Lowland clustering patterns, origin of Lowland varieties, and the …

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Applications Of Phylogenetics To Issues In Freshwater Crayfish Biology, Keith A. Crandall Nov 2005

Applications Of Phylogenetics To Issues In Freshwater Crayfish Biology, Keith A. Crandall

Faculty Publications

Freshwater crayfish have served as model organisms for over 125 years in scientific research, from areas such as neurobiology and vision research to conservation biology and evolution. Recently, evolutionary histories in the form of phylogenies have served as a critical foundation for testing hypotheses in such diverse research areas as well. In this article, I review the amazing diversity of freshwater crayfish, especially in a phylogenetic context and explore how these evolutionary histories have informed crayfish biology and can be used powerfully in the future to guide research in a diversity of areas. Throughout the article, I draw on examples …

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The Role Of Phosducin-Like Protein And The Cytosolic Chaperonin Cct In G Beta Gamma Dimer Assembly, Ting Hu Nov 2005

The Role Of Phosducin-Like Protein And The Cytosolic Chaperonin Cct In G Beta Gamma Dimer Assembly, Ting Hu

Theses and Dissertations

Phosducin-like protein (PhLP), a G protein beta gamma subunit dimer binder and G protein signaling regulator, was suggested to regulate the activity of cytosolic chaperonin CCT by their high affinity interaction. In the present study, the three-dimensional structure of PhLP:CCT complex has been solved by cryoelectron microscopy. PhLP was found to bind only one of the chaperonin rings with both N- and C-terminal domains. It spans the central folding cavity of CCT and interacts with two opposite sides of the top apical region, inducing the constraining of the entry of the folding cavity. These findings support a putative role of …

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Palladium-Imidazolium Carbene Catalyzed Heck Coupling Reactions And Synthesis Of A Novel Class Of Fluoroanthracenylmethyl Ptc Catalysts, Jiuqing Zhang Nov 2005

Palladium-Imidazolium Carbene Catalyzed Heck Coupling Reactions And Synthesis Of A Novel Class Of Fluoroanthracenylmethyl Ptc Catalysts, Jiuqing Zhang

Theses and Dissertations

Palladium catalyzed Heck coupling with aryl and alkenyl halides has become a powerful means of carbon-carbon bond formation. This standard synthetic method has been developed to a high level of utility using various catalysts, conditions and substrates. Yet significant drawbacks remain, including poor reactivity, the need for high temperatures and base, limited substrate generality, and selectivity. Mixed products often suffer from olefin migration following insertion. N-Heterocyclic carbenes (NHC) have proven to be electron-rich donors which provide higher stability and reactivity than phosphines. In a previous paper reported by our research group the imidazolium-palladium carbene has proven to be highly efficient …

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Total Syntheses Of (+)-Geldanamycin, (-)-Ragaglitazar, And (+)-Kurasoin A And Phase-Transfer-Catalyzed Asymmetric Alkylation, Erik J. Hicken Nov 2005

Total Syntheses Of (+)-Geldanamycin, (-)-Ragaglitazar, And (+)-Kurasoin A And Phase-Transfer-Catalyzed Asymmetric Alkylation, Erik J. Hicken

Theses and Dissertations

Geldanamycin possesses various biological activities as seen in the NCI 60 cell line panel (13 nM avg., 70 nM SKBr-3 cells). The predominant mode of action providing these unique results arises from the ability of geldanamycin (GA) to bind to the chaperone heat shock protein 90 (Hsp90). Despite its complicated functionality, the first total synthesis of GA was accomplished, which included two new reactions developed specifically to address the stereochemical features. The final step in the synthesis of GA was a demethylation-oxidation sequence to generate the desired para-quinone. This step could only be accomplished with HNO3/AcOH, producing GA in …

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Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell Oct 2005

Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell

Faculty Publications

Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. Few studies have examined the nociception and stress hormone responses after consumption of soy isoflavones. Methods: In this study, ovariectomized (OVX) female Long-Evans rats were fed either an isoflavone-rich diet (Phyto-600) or an isoflavone-free diet (Phyto-free). We examined the effects of soy isoflavones on metabolism by measuring body weights, food/water intake, adipose tissue weights as well as serum leptin levels. Also, circulating isoflavone levels were quantified. During chemically induced estrous, nociceptive thresholds were recorded. Then, the animals were subjected to a stressor and stress hormone levels were …

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Specific Heat And Thermodynamic Properties Of Metallic Systems: Instrumentation And Analysis, Brian E. Lang Oct 2005

Specific Heat And Thermodynamic Properties Of Metallic Systems: Instrumentation And Analysis, Brian E. Lang

Theses and Dissertations

A small-scale adiabatic calorimeter has been constructed as part of a larger project to study nano-particles and to facilitate specific heat measurements on samples where it is difficult to obtain enough material to run on the current large-scale adiabatic apparatus. This calorimeter is designed to measure sample sizes of less than 0.8 cc over a temperature range from 13 K to 350 K. Specific heat results on copper, sapphire, and benzoic acid show the accuracy of the measurements to be better than ±0.4% for temperatures higher than 50 K. The reproducibility of these measurements is generally better than ±0.25%. Experimental …

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Polymer Microchips For Capillary Electrophoresis And Electric Field Gradient Focusing Of Biomolecules, Ryan Thomas Kelly Sep 2005

Polymer Microchips For Capillary Electrophoresis And Electric Field Gradient Focusing Of Biomolecules, Ryan Thomas Kelly

Theses and Dissertations

Polymeric materials have seen increasing use as microfluidic device substrates due to their low cost and the simplicity of templated fabrication procedures. I showed that poly(methyl methacrylate) (PMMA) microdevices could be enclosed in a boiling water bath, which allowed the seal to form more quickly than in conventional approaches, and enabled microchannels to remain hydrated throughout the bonding process. Microchip capillary electrophoresis (µ-CE) devices were fabricated using water-based enclosure, and a mixture of fluorescently labeled amino acids was separated in 30 s in these microchips. To create more robust capillary electrophoresis (CE) microdevices with improved separation performance, phase-changing sacrificial materials …

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Structure Elucidation Of Bioactive Compounds Isolated From Endophytes Of Alstonia Scholaris And Acmena Graveolens, Nicholas James Hundley Sep 2005

Structure Elucidation Of Bioactive Compounds Isolated From Endophytes Of Alstonia Scholaris And Acmena Graveolens, Nicholas James Hundley

Theses and Dissertations

Alstonia scholaris is an evergreen tree native to Southeast Asia and Australia. It is commonly used as a medicinal plant throughout these regions. In the present study, an endophyte of the genus Xylaria was isolated from a stem of Alstonia scholaris, its mycelia and exudate extracted, and the extract assayed for growth inhibition of HeLa cancer cells in vitro. Several known compounds were isolated and identified based on NMR, infrared, and mass spectral data. The compounds identified are 19,20-epoxycytochalasin C; 19,20epoxycytochalasin D; and xylobovide. Two other compounds, fusaric acid and dehydrofusaric acid, were discovered in an endophyte of the Hypocreales …

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An Acyl Radical Cascade Model For The Total Synthesis Of Lyconadin A, Seth W. Grant Sep 2005

An Acyl Radical Cascade Model For The Total Synthesis Of Lyconadin A, Seth W. Grant

Theses and Dissertations

Lyconadin A (1) is a structurally unique Lycopodium alkaloid with antitumor properties, isolated from the club moss Lycopodium complanatum. We are developing a synthetic route to 1 based on a novel 7-exo-trig/6-exo-trig acyl radical cascade cyclization. The synthesis of model acyl radical cascade precursor 23 will be presented. Key features of this synthesis include the suppression of competing elimination during the alkylation of a hindered phenethyl bromide and the use of a lactone as a precursor to a compound bearing two differentially protected primary alcohols. An account of our studies on the model acyl radical cascade cyclization (23 to 24 …

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Effect Of Melatonin And Dopamine In Site Specific Phosphorylation Of Phosducin In Intact Retina, Arinzechukwu Okere Nkemdirim Aug 2005

Effect Of Melatonin And Dopamine In Site Specific Phosphorylation Of Phosducin In Intact Retina, Arinzechukwu Okere Nkemdirim

Theses and Dissertations

Phosducin (Pdc) is a 28 kDa binding partner for the G protein beta gamma subunit dimer (G-beta-gamma) found abundantly in the photoreceptor cells of the retina and pineal gland. In the retina, light-dependent changes in cAMP and Ca2+ control the phosphorylation of Pdc at serine 73 and 54, respectively, which in turn controls the binding of Pdc to G protein beta gamma subunit dimer . G protein beta gamma subunit dimer binding has been proposed to facilitate light-driven transport of G protein beta gamma subunit dimer from the site of phototransduction in the outer segment of the photoreceptor cell to …

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A Modified Poisson–Boltzmann Analysis Of The Capacitance Behavior Of The Electric Double Layer At Low Temperatures, Douglas Henderson, L. B. Bhuiyan, C. W. Outhwaite Jul 2005

A Modified Poisson–Boltzmann Analysis Of The Capacitance Behavior Of The Electric Double Layer At Low Temperatures, Douglas Henderson, L. B. Bhuiyan, C. W. Outhwaite

Faculty Publications

The modified Poisson–Boltzmann theory is used to analyze the anomalous behavior of the electric double layer capacitance for small surface charge at low temperatures and densities. Good agreement is found with simulation and recent density-functional theory results. Negative adsorption is also found in line with theory and simulation. An unsatisfactory feature is the relatively poor structure in this region due to the inherent approximations in the theory. This feature is unimportant in relation to the capacitance results but has implications when calculating adsorption properties.

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The Effect Of Leisure-Based Screen Time On Physical Activity, Mary Dawn Sperry Jul 2005

The Effect Of Leisure-Based Screen Time On Physical Activity, Mary Dawn Sperry

Theses and Dissertations

The purpose of this study was to determine the effect of leisure-based screen time on physical activity. Ninety-four families participated in this six-week study. Each family was randomly assigned to one of three screen time groups: (1) control group (2) 2-hour-limit group or (3) one-hour-limit group. Family members wore a Walk4Life LS 2505® pedometer to measure steps. Daily screen time logs were filled out each night and leisure-based screen time and steps were recorded. Analysis of variance (steps x group) was used to determine differences among the groups. Univariate tests showed there were no significant differences among any of the …

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The Perceptions Of High School Physical Educators On The Benefits Of Block Scheduling In The State Of Utah, Marilyn Miller Jul 2005

The Perceptions Of High School Physical Educators On The Benefits Of Block Scheduling In The State Of Utah, Marilyn Miller

Theses and Dissertations

The purpose of this research was to examine the extent to which the block schedule is being used in Utah high school physical education, and determine teacher's perceptions of block scheduling in teaching physical education. Block scheduling is a new and more efficient way of organizing the school day. NASPE has found the following positive effects in block scheduling: a better learning environment, more access to stronger curriculum, detailed instruction and demonstrations, and more variety in assessment (NASPE, 2000). Although there were several different forms of the block schedule reported, it appears that a majority of physical educators have discovered …

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Effects Of Long-Term Storage On Quality Of Retail-Packaged Pinto Beans, C. M. Larson, A. R. Sloan, Lynn V. Ogden, Oscar A. Pike Jul 2005

Effects Of Long-Term Storage On Quality Of Retail-Packaged Pinto Beans, C. M. Larson, A. R. Sloan, Lynn V. Ogden, Oscar A. Pike

Faculty Publications

There is interest in storing low-moisture foods for long periods of time for uses such as personal preparedness, disaster relief efforts and space travel. Pinto beans in restaurant-sized No. 10 cans are available in the retail market, but work is needed to determine the effects of long-term storage on quality. The objective of this research was to investigate the quality of retail-packaged pinto beans held at ambient temperatures up to 32 years. Fifteen samples of pinto beans packaged in No. 10 cans, which were treated to remove oxygen, were obtained from donors. Samples ranged from <1 to 32 years in age. Prior to cooking, pinto bean samples were soaked in water containing varying levels of baking soda to standardize textural attributes.

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Hard-Sphere Radial Distribution Function Again, Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak Jul 2005

Hard-Sphere Radial Distribution Function Again, Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak

Faculty Publications

A theoretically based closed-form analytical equation for the radial distribution function, g(r), of a fluid of hard spheres is presented and used to obtain an accurate analytic representation. The method makes use of an analytic expression for the short- and long-range behaviors of g(r), both obtained from the Percus-Yevick equation, in combination with the thermodynamic consistency constraint. Physical arguments then leave only three parameters in the equation of g(r) that are to be solved numerically, whereas all remaining ones are taken from the analytical solution of the Percus-Yevick equation.

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Development Of A Model For The Kinetics And Mechanism Of Nitrogenase, Phillip E. Wilson Jul 2005

Development Of A Model For The Kinetics And Mechanism Of Nitrogenase, Phillip E. Wilson

Theses and Dissertations

Nitrogenase has a central role in the global nitrogen cycle as the enzyme that catalyzes the reduction of atmospheric N2 to NH3. Fixed nitrogen is generally limiting in the environment and in agriculture, so nitrogenase has received much attention as an alternative to nitrogen fertilizers. Characterizing the mechanism of nitrogenase is the goal of this work. The molybdenum nitrogenase enzyme system is comprised of the MoFe protein and the Fe protein. Interactions between these proteins and nucleotides are crucial to catalysis. An important approach to characterize these interactions is to correlate the kinetics of nitrogenase catalysis to a mechanism based …

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Angiotensin Ii-Mediated Regulation Of The Human Angiotensin Ii Type 1 Receptor Gene, Xylophone Vijai Aasee Victor Jul 2005

Angiotensin Ii-Mediated Regulation Of The Human Angiotensin Ii Type 1 Receptor Gene, Xylophone Vijai Aasee Victor

Theses and Dissertations

The physiological responses of angiotensin II (Ang II) are mediated across the cell membrane through the angiotensin II type 1 receptor (AT1R), a heptahelical membrane protein coupled to trimeric G-proteins on the cytosolic side. AT1R on binding its ligand, Ang II, leads to downregulation of cell-surface receptor and also its mRNA. We have investigated whether the 3'- and 5'-untranslated regions of the human AT1R mRNA mediate the degradation of hAT1R mRNA by post-transcriptional mechanisms in human adrenocortical carcinoma cell line (H295R cells). Protein kinase C (PKC) activator, phorbol-12-myristate-13-acetate (PMA), showed that the downregulation of hAT1R mRNA is mediated by the …

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Homologous Strand Exchange And Dna Helicase Activities In Plant Mitochondria, Daqing Song Jul 2005

Homologous Strand Exchange And Dna Helicase Activities In Plant Mitochondria, Daqing Song

Theses and Dissertations

Homologous recombination is critical for generating genetic variation in living organisms by exchange and rearrangement of DNA. Most of our knowledge about homologous recombination is limited to processes in bacteria or in eukaryotic nuclei. In E. coli, homologous recombination is dependent on the RecA protein. Higher plant chloroplasts have RecA-like strand exchange activity. However, little is known about these mechanisms in higher plant mitochondria. I have detected a RecA-like strand exchange activity in soybean mitochondria. This activity forms joint molecules in the presence of ATP, Mg2+, and homologous DNA substrates. In addition, the E. coli single-stranded DNA binding (SSB) protein …

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Genetic Analysis Of Conserved Residues In Phou Of Escherichia Coli, Stewart G. Gardner Jul 2005

Genetic Analysis Of Conserved Residues In Phou Of Escherichia Coli, Stewart G. Gardner

Theses and Dissertations

The Pho regulon is controlled by the PstSCAB transporter, PhoU, and the two-component proteins, PhoB and PhoR. PhoU is a negative regulator of the Pho regulon under phosphate-replete conditions. How PhoU functions is unknown. Many PhoU homologues are found widely throughout prokaryotic domains. There are several conserved amino acid residues in the PhoU protein. It is hypothesized that these residues play an important role in the function of PhoU. To test this hypothesis, several site directed mutations in the phoU gene have been produced with single amino acid changes in conserved residues. After testing these mutants, it was found that …

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Time Efficiency In Computer Assisted Direct Observation Of Physical Activity Using Sofit, Trisha Anderson Jul 2005

Time Efficiency In Computer Assisted Direct Observation Of Physical Activity Using Sofit, Trisha Anderson

Theses and Dissertations

Having valid and reliable methods for assessing physical activity levels is critical to understanding physical activity patterns. Direct observation is a widely used technique for obtaining contextually rich data on physical activity levels in physical education classes. One major limitation of direct observation is that it is time intensive. The use of digital video editing software programs may lessen the amount of time needed to gather the data. The purpose of this study was to compare the amount of time needed to obtain SOFIT (System for Observing Fitness Instruction Time) physical activity data using the traditional paper and pencil method …

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