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The Chick Embryo Amnion As An In Vitro Culture System For Ivf And Nt Embryos, Tonya Renea Davidson Jan 2004

The Chick Embryo Amnion As An In Vitro Culture System For Ivf And Nt Embryos, Tonya Renea Davidson

LSU Doctoral Dissertations

Calving rates are significantly reduced following in vitro production of embryos. Thus, if a technique could be developed that would increase calving rates by as little as one viable offspring, significant research advances could be made. Therefore, in a series of experiments, the efficiency and quality of culturing IVP bovine embryos in the amnion of a domestic chicken egg was tested. In Experiment I, by culturing IVP bovine embryos in the chick amnion (day 4 to 7 of incubation) it was discovered that there was no significant difference in blastocyst rates compared with controls. In Experiment II, it was shown …

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Synthesis And Antibacterial Assessment Of Water-Soluble Hydrophobic Chitosan Derivatives Bearing Quaternary Ammonium Functionality, Mrunal R. Thatte Jan 2004

Synthesis And Antibacterial Assessment Of Water-Soluble Hydrophobic Chitosan Derivatives Bearing Quaternary Ammonium Functionality, Mrunal R. Thatte

LSU Doctoral Dissertations

Chitosan is a naturally occurring, bio-degradable, non-toxic, non-allergenic bio-polysaccharide derived from chitin, found in abundance in nature. Studies aimed at deriving newer applications of chitosan are hence of interest. Among these, one of the focuses of investigations is aimed at excellent antimicrobial activity demonstrated by chitosan. In this context, certain quaternary ammonium derivatives of chitosan have been shown in the past to be highly effective antibacterial materials. In the present study, substituted chitosan derivatives were synthesized and further quaternized using Quat-188 to produce water soluble derivatives at neutral pH. The antibacterial assessments of the quaternized derivatives of substituted chitosan were …

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New Insights Into The Binding Site Formation And The Performance Of Molecularly Imprinted Polymers, Hyunjung Kim Jan 2004

New Insights Into The Binding Site Formation And The Performance Of Molecularly Imprinted Polymers, Hyunjung Kim

LSU Doctoral Dissertations

Molecularly imprinted polymers (MIPs) are finding important applications in the field of separation science, catalysis, sensor, and immunoassays. To optimize the performance of the MIPs, it is essential to understand the underlying mechanism of the process. This research focuses on understanding binding site formation and performance, and improvement of the MIPs. Chapter 1 introduces the concept of the MIPs, and binding isotherm and affinity distribution of heterogeneous binding sites in the MIPs. Chapter 2 describes fundamental studies conducted to understand the binding site formation of the MIPs. The number of binding sites (N) and the number average association constant (Kn) …

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Assessment Of Instructional Methodologies And Student Information Processing Styles In A Terrorism Preparedness Course, William James Mccarthy Jan 2004

Assessment Of Instructional Methodologies And Student Information Processing Styles In A Terrorism Preparedness Course, William James Mccarthy

LSU Doctoral Dissertations

The focus of the research was the evaluation of two instructional methodologies for teaching terrorism preparedness at several universities in Louisiana. Participants were taught a curriculum for an audience who may work at a potential terrorist target. The purpose of the research was to determine if processing styles based instruction improved learning. The objectives of the study were to: 1) Describe participant demographics: a) age, b) gender, c) credit hours, d) field of study; and e) preferred Strategic Information Processing Style (SIPS); 2) Determine if changes occur in knowledge of terrorism preparedness as measured by the Terrorism Awareness test; 3) …

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Developing Embryo Technologies For The Eland Antelope (Taurotragus Oryx), Gemechu G. Wirtu Jan 2004

Developing Embryo Technologies For The Eland Antelope (Taurotragus Oryx), Gemechu G. Wirtu

LSU Doctoral Dissertations

Assisted reproductive technologies developed in domestic cattle serve as a starting point in similar studies on nondomestic bovids. The common eland is a useful model species for studies on rare tragelaphine antelopes. In Chapter 3 of the present study, effects of components/attributes of protein-free embryo culture media on the in vitro development of in vitro-derived bovine embryos were evaluated. A 2 x 2 factorial study comparing effects of groups of amino acids (20aa or 11aa) in two base media (modified KSOM or BM-3) demonstrated that amino acids and base medium affected embryonic development. A subsequent 7 x 2 factorial experiment …

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Modeling Longleaf Pine (Pinus Palustris Mill) Wood Properties Using Near Infrared Spectroscopy, Brian Kipling Via Jan 2004

Modeling Longleaf Pine (Pinus Palustris Mill) Wood Properties Using Near Infrared Spectroscopy, Brian Kipling Via

LSU Doctoral Dissertations

This research demonstrated model development for important wood properties using near infrared spectroscopy (NIR); it considered the effect of outside sources of error, and the ability of NIR to measure fiber morphology. Strength, stiffness, and density were successfully modeled from wood samples taken throughout 10 longleaf (Pinus palustris Mill) trees. Principal components and multiple linear regression were compared for performance in prediction of density, strength, and stiffness. I found both modeling techniques to yield similar prediction accuracies. However, I found that density could be estimated through Beer-Lambert’s law since the absorbance at all wavelengths increased with density. Also, 5 of …

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Being Otherworldly In The World: Michael Oakeshott On Religion, Aesthetics And Politics, Elizabeth Campbell Corey Jan 2004

Being Otherworldly In The World: Michael Oakeshott On Religion, Aesthetics And Politics, Elizabeth Campbell Corey

LSU Doctoral Dissertations

This dissertation is a study of the thought of Michael Oakeshott with particular emphasis on his writings about the character of religion and aesthetics. The dissertation as a whole makes the case that a certain moral vision-one informed by religious and aesthetic considerations-lies at the center of Oakeshott's thought and informs his political philosophy. The dissertation begins as an examination of Oakeshott's debts to St. Augustine and to British Idealist thinkers such as F. H. Bradley, and moves to a study of Oakeshott's own views on religion and aesthetics. It turns next to a consideration of Oakeshott's two essays entitled …

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Tissue Culture And Transformation Of Introducing Genes Useful For Pest Management In Rice, Shuli Zhang Jan 2004

Tissue Culture And Transformation Of Introducing Genes Useful For Pest Management In Rice, Shuli Zhang

LSU Doctoral Dissertations

Sheath blight (SB), caused by Rhizoctonia solani K¨¹hn, is a major rice disease internationally and in the southern rice area of the Unites States, including Louisiana. Breeders have incorporated partial resistance into commercial rice varieties to control the disease, but a higher level of resistance is needed. It has been demonstrated that the pathogenesis-related (PR) proteins ¦Â-1, 3-glucanase and chitinase are components of effective defense mechanisms for protecting plants against fungal pathogens. This research was conducted to co-transform the ¦Â-1, 3-glucanase, chitinase and bar genes into the rice variety Taipei 309 using the hpt gene for resistance to hygromycin B …

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Imidazolinone-Tolerant Rice: Weed Control, Crop Response, And Environmental Impact, Ronald Joseph Levy, Jr. Jan 2004

Imidazolinone-Tolerant Rice: Weed Control, Crop Response, And Environmental Impact, Ronald Joseph Levy, Jr.

LSU Doctoral Dissertations

Field and greenhouse research was conducted from 1999 to 2003 to evaluate weed control in imidazolinone-tolerant (IT) rice (Oryza sativa L.) under various tillage and planting systems, tolerance of IT rice cultivars to imazethapyr rate and application timing, and the impact of IT technology and tillage systems on solids runoff in rice drainage water. In both conventional and reduced tillage systems imazethapyr applied preemergence and postemergence at 70 g ai/ha controlled red rice (Oryza sativa L.), barnyardgrass [Echinochloa crus-galli (L.) Beauv.], Amazon sprangletop [Leptochloa panicoides (Presl) Hitchc.], and rice flatsedge (Cyperus iria L.) 87 to 99%. Indian jointvetch (Aeschynomene indica …

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A Basic Interpretative Analysis Of Instrumental Music Education Majors' Approaches To Score Study In Varying Musical Contexts, Jeremy S. Lane Jan 2004

A Basic Interpretative Analysis Of Instrumental Music Education Majors' Approaches To Score Study In Varying Musical Contexts, Jeremy S. Lane

LSU Doctoral Dissertations

The purposes of this qualitative study were to 1) provide a holistic description of procedures used by undergraduate instrumental music education majors (N = 21) in music score study tasks; 2) examine relationships among these procedures and their use in varying musical contexts; 3) examine relationships among score study tendencies, education level, and overall musical ability; and 4) provide general comparisons of undergraduate music education majors’ score study procedures and those implied by expert conductors’ major disciplinary ways of thinking. Each subject participated in two one-on-one interview sessions with the investigator. During each session, subjects “thought out loud” as they …

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Interactions Of Insect Herbivory And Multiple Abiotic Stress Agents On Two Wetland Tree Species In Southeast Louisiana Swamps, Rebecca Faye Souther-Effler Jan 2004

Interactions Of Insect Herbivory And Multiple Abiotic Stress Agents On Two Wetland Tree Species In Southeast Louisiana Swamps, Rebecca Faye Souther-Effler

LSU Doctoral Dissertations

Forested wetlands in Louisiana are hydrologically isolated from the Mississippi River, impounded by manmade structures, impacted by saltwater intrusion, and are sinking, resulting in more frequent flooding for longer periods. Additionally, defoliation of the two dominant trees, baldcypress (Taxodium distichum L. Rich) and water tupelo (Nyssa aquatica L.), occur frequently during spring. In Louisiana, the baldcypress leafroller, BCLR, (Archips goyerana Kruse) and the forest tent caterpillar, FTC, (Malacosoma disstria Hubner) defoliate up to 120,000ha of baldcypress-tupelo swamps. Restoration plans call for reintroducing Mississippi River water (diversions) to increase sediment elevation, promote natural regeneration, and enhance primary and secondary productivity. In …

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Applying The Transtheoretical Model To Promote Greater Fruit And Vegetable Consumption: A Successful Approach To Maintaining Behavioral Change, Hiba Ahmad Bawadi Jan 2004

Applying The Transtheoretical Model To Promote Greater Fruit And Vegetable Consumption: A Successful Approach To Maintaining Behavioral Change, Hiba Ahmad Bawadi

LSU Doctoral Dissertations

The purpose of this study was to investigate the response of participants in the first three Stages of Change (SOC) to a preparation stage-tailored intervention to increase fruit and vegetable (F&V) consumption. An on-line survey was delivered to 400 university employees, and included questionnaires about their demographic information, SOC, self efficacy (SE), and decisional balance (DB). One hundred fifty six (39%) responded to the survey. A total of 40 were selected from the first three stages, precontemplation (PC), contemplation (C), and preparation (P), and were assigned into two groups (PC/C and P) with consideration to the best possible matching in …

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Herbivore Movement And Spatial Population Dynamics In A Heterogeneous Landscape, Kyle Jonathan Haynes Jan 2004

Herbivore Movement And Spatial Population Dynamics In A Heterogeneous Landscape, Kyle Jonathan Haynes

LSU Doctoral Dissertations

To date, few metapopulation studies have isolated the effects of the intervening matrix from other attributes of landscape structure (e.g., patch geography or quality) that might influence dispersal among patches. Furthermore, there has been little exploration of the mechanisms underlying effects of the matrix on the spatial ecology of species. In this dissertation, I examine how the movement and distribution of the planthopper Prokelisia crocea within and among host-plant patches (prairie cordgrass, Spartina pectinata) is affected by the composition of the matrix (the invasive grass smooth brome [Bromus inermis], native non-host grasses, or mudflat). First, using a mark-recapture study in …

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Biology And Host Finding Of Predaceous Hister Beetles (Coleoptera: Histeridae) Associated With Ips Spp. (Coleoptera: Scolytidae) In Loblolly Pine (Pinus Taeda L.), William Pinson Shepherd Jan 2004

Biology And Host Finding Of Predaceous Hister Beetles (Coleoptera: Histeridae) Associated With Ips Spp. (Coleoptera: Scolytidae) In Loblolly Pine (Pinus Taeda L.), William Pinson Shepherd

LSU Doctoral Dissertations

The most common predaceous Histeridae (Coleoptera) found associated with Ips engraver beetles (Coleoptera: Scolytidae) in Louisiana were Platysoma attenuata LeConte, Pla. cylindrica (Paykull), Pla. parallelum (Say), and Plegaderus transversus (Say). Seasonal abundance of histerids in flight traps coincided with Ips spp. activity in the area. Histerid adults arrived at loblolly pine (Pinus taeda L.) logs one wk after Ips attacks had begun. As a group, histerids exhibited a bimodal emergence pattern with the first peak occurring during Ips emergence and a second four wks later, indicating that they fed on bark beetles and associated organisms arriving later in the colonization …

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Preservation Of Sperm Harvested From The Rat, Caprine, Equine, And Bovine Epididymis, Aida Nioma James Jan 2004

Preservation Of Sperm Harvested From The Rat, Caprine, Equine, And Bovine Epididymis, Aida Nioma James

LSU Doctoral Dissertations

The interest in preserving endangered species has increased the amount of attention lent to the recovery of functional sperm from the epididymides of deceased males (Foote, 2000). Postmortem specimens have a finite time period before decomposition affects functionality. Determination of this “window of opportunity” to harvest and preserve epididymal sperm would be beneficial for further research in sperm preservation and assisted reproductive technologies. The objective of these studies was to determine 1) the “window of opportunity” to collect viable rat, caprine, equine and bovine epididymal sperm, 2) if epididymal sperm collected could be cryopreserved, 3) to test two common cryoprotectants …

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Evaluation Of Injury And Management Strategies For Stink Bugs (Heteroptera: Pentatomidae) On Cotton, Gossypium Hirsutum L., Melissa Marie Willrich Jan 2004

Evaluation Of Injury And Management Strategies For Stink Bugs (Heteroptera: Pentatomidae) On Cotton, Gossypium Hirsutum L., Melissa Marie Willrich

LSU Doctoral Dissertations

The effects of brown stink bug, Euschistus servus (Say), and southern green stink bug, Nezara viridula (L.), feeding on pre-flowering, flowering, and senescing cotton, Gossypium hirsutum L., plants were evaluated in field studies. Vegetative stage seedlings and flower buds (squares) were not significantly injured by adults or nymphs of either species in no-choice studies. Brown stink bug adults induced boll abscission, and reduced seedcotton yield and seed germination in bolls accumulating „T 350, „T 550, and 101 to „T 600 heat units beyond anthesis, respectively. In free-choice tests, boll preference was evaluated during each of the initial five weeks of …

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Flesh And Spirit Onstage: Chronotopes Of Performance In Medieval English Theatre, Gregory Lee Cavenaugh Jan 2004

Flesh And Spirit Onstage: Chronotopes Of Performance In Medieval English Theatre, Gregory Lee Cavenaugh

LSU Doctoral Dissertations

This study uses Mikhail Bakhtin's chronotope, which is the informing principle of one's experience of space and time, to explore different relations among space, time, actors, and audience in medieval theatre. Relations between the material and spiritual worlds as understood in the Middle Ages are considered in the context of relations between performers and audience members with two goals. First, I explore how the ontological status of the metaworld created through performance changed in the context of specific chronotopes. Second, I explore how diverse religious discourses affected medieval modes of representation. This study posits three chronotopes of performance informing medieval …

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Spectroscopic Investigation Of Nitrogenase: Epr And Mcd Studies Of The Femo Cofactor And The P-Cluster, Robyn B. Broach Jan 2004

Spectroscopic Investigation Of Nitrogenase: Epr And Mcd Studies Of The Femo Cofactor And The P-Cluster, Robyn B. Broach

LSU Doctoral Dissertations

Little is known about substrate binding and reduction of nitrogenase. EPR spectroscopy is used here to observe intermediate states generated by different substrates. Two different spin states (S=3/2 and S=1/2) were exhibited for each substrate, which may result from different binding of the substrate to the cofactor (side-on or terminal binding) or the difference of the substrate binding to either Fe or Mo of the cofactor. Parallel studies were performed on a variant MoFe protein, alpha-195Gln, which exhibited different signals from the wild-type suggesting that the substituted amino acid maybe necessary to reach some mechanistic states that the …

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Effects Of Gp130 Cytokines On Adipocytes, Sanjin Zvonic Jan 2004

Effects Of Gp130 Cytokines On Adipocytes, Sanjin Zvonic

LSU Doctoral Dissertations

Members of the gp130 cytokine family are known for their pleiotropic roles in various cell types. Our work has focused on their actions in adipocytes. CNTF administration has been shown to ameliorate most complications associated with obesity and type 2 diabetes through an unknown mechanism. In this study CNTF is shown to activate JAK/STAT and MAPK signaling, both in vitro and in vivo. In 3T3-L1 adipocytes, chronic CNTF also regulates the expression of SREBP-1, FAS, IRS-1 and GLUT4. Acute CNTF administration enhances the activation of IRS-1 and Akt by insulin. Our data also demonstrate that the expression of CNTF-specific receptor, …

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Seasonal Occurrence Of Phyllophaga Species And Biological Studies Of Phyllophage Ephilida (Say) On Sweet Potato, Ipomoea Batatas (L) Lam, In Louisiana, Aboubacar Diagne Jan 2004

Seasonal Occurrence Of Phyllophaga Species And Biological Studies Of Phyllophage Ephilida (Say) On Sweet Potato, Ipomoea Batatas (L) Lam, In Louisiana, Aboubacar Diagne

LSU Doctoral Dissertations

The biology of Phyllophaga ephilida (Say) was studied in Louisiana with both laboratory and field experiments from 1998 through 2003. The seasonal occurrence of common adult Phyllophaga species in sweet potato growing areas was surveyed with blacklight traps. P. ephilida and P. crinita (Burmeister) were the most common species at all locations. The attractiveness of seven methyl esters of L-isoleucine and L-valine blends to P. ephilida males was evaluated in sweet potato fields in 1999 and 2000. The 100% methyl ester of L-isoleucine was significantly more attractive than all other blend ratios that were tested. The life cycle of P. …

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Comparison Studies Of The Mechanistic Formation Of Polyhalogentaed Dibenzo-P-Dioxins And Furans From The Thermal Degradation Of 2-Bromophenol And 2-Chlorophenol, Catherine Spearing Evans Jan 2004

Comparison Studies Of The Mechanistic Formation Of Polyhalogentaed Dibenzo-P-Dioxins And Furans From The Thermal Degradation Of 2-Bromophenol And 2-Chlorophenol, Catherine Spearing Evans

LSU Doctoral Dissertations

Emissions of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and polybrominated dibenzo-p-dioxins and furans (PBDD/Fs) from hazardous waste incinerators, and many other sources for combustion have been considered environmentally hazardous and a major health threat. Recently, a growing number of materials containing brominated hydrocarbons, commonly used flame retardants, have been disposed in municipal and hazardous waste incinerators. This results in the increased potential for formation of PBDD/Fs and other hazardous combustion by-products. In contrast to chlorinated hydrocarbons, the reactions of brominated hydrocarbons have been studied only minimally. In fact, studies have shown that brominated phenols form higher yields of PBDD/Fs than the …

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Dynamics Of Complex Polymer Solutions: Putting Diffusion To Work And Exploring Rigid Rod Diffusion, Garrett John Doucet Jan 2004

Dynamics Of Complex Polymer Solutions: Putting Diffusion To Work And Exploring Rigid Rod Diffusion, Garrett John Doucet

LSU Doctoral Dissertations

This dissertation is concerned with random coil and rodlike polymer diffusion in complex solutions. The development of fluorescence photobleaching recovery, FPR, as a technique to determine polymer molecular weight distributions by measuring the diffusion distribution and converting it to a molecular weight distribution using a calibration curve is first covered. Fluorescently tagged probes were individually dissolved in polymer solutions at negligible amounts and measured with FPR to construct the calibration curve of self-diffusion vs. molecular weight. Once calibration curves were constructed, bimodal distributions were separated using the matrices corresponding to the calibration curves. The diffusion of the probes and separation …

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The Contributions Of Floyd Leslie Sandle To Black Educational Theatre In Louisiana, Ava Marie Brewster-Turner Jan 2004

The Contributions Of Floyd Leslie Sandle To Black Educational Theatre In Louisiana, Ava Marie Brewster-Turner

LSU Doctoral Dissertations

Floyd Leslie Sandle appeared on the theatrical scene in 1938 on the campus of Grambling State University. From his humble beginnings in the segregated town of Magnolia, Mississippi, to Dillard University where his passion for theatre was nurtured by Dr. Sheppard Randolph Edmonds, Sandle made significant strides in the dvelopment of Black Educational Theatre in Louisiana. Through his unique approach of presenting plays to the residents of the rural community of Grambling, Louisiana, Sandle was able to establish a state certified Speech and Drama Department at Grambling State University. He trained students in educational theatre though his lectures, laboratory experiences, …

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Pan African Narratives: Sites Of Resistance In The Black Diaspora, Anita Louise Harris Jan 2004

Pan African Narratives: Sites Of Resistance In The Black Diaspora, Anita Louise Harris

LSU Doctoral Dissertations

Africa as a point of reference for Africans dispersed from her shores and their descendants in the Diaspora has perpetuated discourse of longing and ambivalence. For centuries these various sentiments have emerged in Black literary expressions. The quest of this study is to advance Black narrative tradition by proposing a theoretical framework informed by these constructs and predicaments to establish a genre of literature referred to here as Pan African narratives. This work looks at Black response to the dilemma of dispersal and dislocation in the Diaspora from the nineteenth to the twentieth century. More specifically, it examines the emergence …

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Agouti Expression In Human Adipose Tissue: Functional Consequences And Increased Expression In Type 2 Diabetes, Steven R. Smith, Barbara Gawronska-Kozak, Lenka Janderová, Taylor Nguyen, Angela Murrel, Jacqueline M. Stephens, Randall L. Mynatt Dec 2003

Agouti Expression In Human Adipose Tissue: Functional Consequences And Increased Expression In Type 2 Diabetes, Steven R. Smith, Barbara Gawronska-Kozak, Lenka Janderová, Taylor Nguyen, Angela Murrel, Jacqueline M. Stephens, Randall L. Mynatt

Faculty Publications

It is well recognized that the agouti/melanocortin system is an important regulator of body weight homeostasis. Given that agouti is expressed in human adipose tissue and that the ectopic expression of agouti in adipose tissue results in moderately obese mice, the link between agouti expression in human adipose tissue and obesity/type 2 diabetes was investigated. Although there was no apparent relationship between agouti mRNA levels and BMI, agouti mRNA levels were significantly elevated in subjects with type 2 diabetes. The regulation of agouti in cultured human adipocytes revealed that insulin did not regulate agouti mRNA, whereas dexamethasone treatment potently increased …

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Rubisco Activase Is Required For Optimal Photosynthesis In The Green Alga Chlamydomonas Reinhardtii In A Low-Co2 Atmosphere, Steve V. Pollock, Sergio L. Colombo, Davey L. Prout, Ashley C. Godfrey, James V. Moroney Dec 2003

Rubisco Activase Is Required For Optimal Photosynthesis In The Green Alga Chlamydomonas Reinhardtii In A Low-Co2 Atmosphere, Steve V. Pollock, Sergio L. Colombo, Davey L. Prout, Ashley C. Godfrey, James V. Moroney

Faculty Publications

This report describes a Chlamydomonas reinhardtii mutant that lacks Rubisco activase (Rca). Using the BleR (bleomycin resistance) gene as a positive selectable marker for nuclear transformation, an insertional mutagenesis screen was performed to select for cells that required a high-CO2 atmosphere for optimal growth. The DNA flanking the Ble R insert of one of the high-CO2-requiring strains was cloned using thermal asymmetric interlaced-polymerase chain reaction and inverse polymerase chain reaction and sequenced. The flanking sequence matched the C. reinhardtii Rca cDNA sequence previously deposited in the National Center for Biotechnology Information database. The loss of a functional Rca in the …

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Molecular And Culture-Based Analyses Of Aerobic Carbon Monoxide Oxidizer Diversity, Gary M. King Dec 2003

Molecular And Culture-Based Analyses Of Aerobic Carbon Monoxide Oxidizer Diversity, Gary M. King

Faculty Publications

Isolates belonging to six genera not previously known to oxidize CO were obtained from enrichments with aquatic and terrestrial plants. DNA from these and other isolates was used in PCR assays of the gene for the large subunit of carbon monoxide dehydrogenase (coxL). CoxL and putative coxL fragments were amplified from known CO oxidizers (e.g., Oligotropha carboxidovorans and Bradyrhizobium japonicum), from novel CO-oxidizing isolates (e.g., Aminobacter sp. strain COX, Burkholderia sp. strain LUP, Mesorhizobium sp. strain NMB1, Stappia strains M4 and M8, Stenotrophomonas sp. strain LUP, and Xanthobacter sp. strain COX), and from several well-known isolates for which the capacity …

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Annotations, Cwbr_Editor Dec 2003

Annotations, Cwbr_Editor

Civil War Book Review

No abstract provided.

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Uptake Of Carbon Monoxide And Hydrogen At Environmentally Relevant Concentrations By Mycobacteria, Gary M. King Dec 2003

Uptake Of Carbon Monoxide And Hydrogen At Environmentally Relevant Concentrations By Mycobacteria, Gary M. King

Faculty Publications

Liquid culture assays revealed a previously unreported capacity for Mycobacterium bovis BCG, M. gordonae, and M. marinum to oxidize CO and for M. smegmatis to consume molecular hydrogen. M. bovis BCG, M. gordonae, M. smegmatis, and M. tuberculosis H37Ra oxidized CO at environmentally relevant concentrations (<50 >ppm); H2 oxidation by M. gordonae and M. smegmatis also occurred at environmentally relevant concentrations (< 10 ppm). CO was not consumed by M. avium or M. microti, although the latter appeared to possess CO dehydrogenase (CODH) genes based on PCR results with primers designed for the CODH large subunit, coxL. M. smegmatis and M. gordonae oxidized CO under suboxic (10 and 1% atmospheric oxygen) and anoxic conditions in the presence of nitrate; no oxidation occurred under anoxic conditions without nitrate. Similar results were obtained for H2 oxidation by M. smegmatis. Phylogenetic analyses of coxL PCR products indicated that mycobacterial sequences form a subclade distinct from that of other bacterial coxL, with limited differentiation among fast- and slow-growing strains.

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Rates Of Species Loss From Amazonian Forest Fragments, Gonçalo Ferraz, Gareth J. Russell, Philip C. Stouffer, Richard O. Bierregaard, Stuart L. Pimm, Thomas E. Lovejoy Nov 2003

Rates Of Species Loss From Amazonian Forest Fragments, Gonçalo Ferraz, Gareth J. Russell, Philip C. Stouffer, Richard O. Bierregaard, Stuart L. Pimm, Thomas E. Lovejoy

Faculty Publications

In the face of worldwide habitat fragmentation, managers need to devise a time frame for action. We ask how fast do understory bird species disappear from experimentally isolated plots in the Biological Dynamics of Forest Fragments Project, central Amazon, Brazil. Our data consist of mist-net records obtained over a period of 13 years in 11 sites of 1, 10, and 100 hectares. The numbers of captures per species per unit time, analyzed under different simplifying assumptions, reveal a set of species-loss curves. From those declining numbers, we derive a scaling rule for the time it takes to lose half the …

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