Digital Commons Network^™

The Multiple Dimensions Of The Interfirm Network: The Critical Sources Of Product Innovation, Thongchai Srivardhana

LSU Doctoral Dissertations

This dissertation examines the impacts of interfirm variables on both invention and commercialization activities, following Greve’s (2003) suggestion that innovation research will be enriched if more studies integrate invention and commercialization activities to understand the entire innovation development process. Utilizing two established theoretical perspectives—organizational learning and institutional theory—six sets of hypotheses are developed containing the following interfirm variables: 1) direct and indirect ties, 2) strength of direct ties, 3) structural holes, 4) prominence of direct partners, 5) exploration and exploitation partners, and 6) horizontal and vertical networks. The dissertation also predicts that these interfirm variables would contribute to either invention …

The Relationship Between Mania And Feeding/Mealtime Behavior Problems Among Persons With Intellectual Disability, Rinita Laud

LSU Doctoral Dissertations

This study represents the first to assess whether a relationship between mania and feeding/mealtime behavior problems exists in individuals with ID. Participants were compared across three groups (manic, non-manic psychiatrically impaired, and controls) on subscales and items of the Screening Tool for fEeding Problems (STEP). An attempt was made to assess for differences in problematic feeding behavior. Individuals in the manic group exhibited clinically significant symptoms of mania (n = 18), those in the non-manic psychiatrically impaired group exhibited symptoms of psychopathology other than mania (n = 18), and those in the control group did not exhibit symptoms of mania …

Mindfulness Meditation: Creative Musical Performance Through Awareness, Sheri Oyan

LSU Doctoral Dissertations

Musicians spend countless hours practicing their instruments over the course of a lifetime. These hours are primarily spent learning how to manipulate the instrument through scale studies, etudes, and repertoire. However, despite intense and diligent effort, many musicians find themselves unable to perform for an audience without some kind of interruption in creativity in the form of mental and/or physical distractions. The symptoms of such distractions can include heart palpitations, muscle tension, shaking, feelings of fear and panic, and an inability to focus on the task at hand. The presence of these symptoms, typically referred to as “performance anxiety,” is, …

Characterization Of Equine Pulmonary Endothelin Receptors In Health And Disease, Sumanth Polikepahad

LSU Doctoral Dissertations

Endothelin-1 (ET-1) has been implicated in allergic type of respiratory inflammatory diseases in various species of animals including horses. This peptide elicits its actions by acting through endothelin-A (ET-A) and endothelin-B (ET-B) receptor sub-types. In this project, we have hypothesized that endothelin receptors (both ET-A and ET-B) are altered in terms of affinity and expression, in the lungs of summer pasture-associated obstructive pulmonary disease (SPAOPD)-affected horses. Objective of this dissertation was to determine the alterations in the affinity and expression of endothelin receptors in the lungs of healthy and SPAOPD-affected horses. To pursue our hypothesis, we have employed pharmacological, immunohistochemical …

A Neural Network Model For Classification Of Coastal Wetlands Vegetation Structure With Moderate Resolution Imaging Spectro-Radiometer (Modis) Data, Evaristo Joseph Liwa

LSU Doctoral Dissertations

Mapping coastal marshes is an important component in the management of coastal environments. Classification of marshes using remote sensing data has traditionally been performed by employing either parametric supervised classification algorithms or unsupervised classification algorithms. The implementation of these conversional classification methods is based on the underlying distributions concerning the probability density functions (PDF). Neural networks provide a practical approach to this classification because they are essentially non-parametric data transformations that are not restricted by any underlying assumptions. The major objective of this study was to evaluate the ability of neural networks using Moderate Resolution Imaging Spectro-radiometer (MODIS) data to …

Ecology Of Lesser Scaup Amphipods In The Upper-Midwest: Scope And Mechanisms Of The Spring Condition Hypothesis And Implications For Migration Habitat Conservation, Michael Jason Anteau

LSU Doctoral Dissertations

I tested the scope of the Spring Condition Hypothesis in explaining the continental population decline of lesser scaup (Aythya affinis; hereafter scaup) and explored potential mechanisms affecting female body condition to assist conservation efforts for population recovery. Lipid reserves of females currently are lower than historical values during spring migration throughout Iowa, Minnesota, and North Dakota; females catabolized lipids throughout this area (indexed by concentrations of plasma-lipid metabolites, which accounted for 75% of the variation in mass change). My results indicate that a large segment of the continental scaup population likely is affected by decreased lipid reserves, which could cause …

Biomechanical Characteristics Of Low Back Tissues During Trunk Flexion-Extension, Michael William Olson

LSU Doctoral Dissertations

Analysis of the mechanical and neural regulatory mechanisms of the flexion-relaxation phenomenon (FRP), observed in deep trunk flexion, was performed since it is believed these mechanisms provide insight into the causes of low back injury and pain. Three methods were used to analyze the behavior of the lumbar tissues during trunk flexion-extension exercises: 1) active continuous cyclic movement, 2) acute cyclic movement at different orientations, and 3) passive continuous cyclic movement. All activities were performed at a rate of 0.1 Hz (6 cycles•min-1) while monitoring the surface electromyography (EMG) of the lumbar paraspinal muscles. Abdominal, hamstring, and quadriceps muscle activities …

The Regulation Of Genes Involved In Trichome Development, Matthew Lloyd Brown

LSU Doctoral Dissertations

Arabidopsis thaliana is an organism that can be used as a model for most of the processes that occur in flowering plants. The leaf hairs, or trichomes, of Arabidopsis thaliana are macroscopic single cells that have been used as a model system for cell fate determination, cell expansion, cell cycle regulation, cell wall deposition, as well as other processes. Initiation of the trichome cell fate is controlled by a complex of genes including GLABRA1 (GL1), TRANSPARENT TESTA GLABRA (TTG), and GLABRA3 (GL3). This work examines the role of GL3 in trichome initiation and uses plants expressing varying levels of GL3 …

Power Analysis For A Mixed Effects Logistic Regression Model, Yinmei Li

LSU Doctoral Dissertations

In herd health studies, the mixed effects logistic regression model with random herd effects are commonly used for modeling clustered binary data. These models are well developed and widely used in the literature, among which is the logistic-normal regression model. In contrast to the rich literature in modeling methods, the sample size/power analysis methods for such mixed effects models are sparse. The sample size/power analysis method for the logistic-normal regression model is not readily available. This study is to develop a power analysis/sample size estimation method for the logistic-normal regression model. Extended from the sample size method for the likelihood …

The Scent Of A New World Novel: Translating The Olfactory Language Of Faulkner And García Márquez, Terri Smith Ruckel

LSU Doctoral Dissertations

Both William Faulkner and Gabriel García Márquez introduce the olfactory as a focal element in their writing, producing works that challenge the singular primacy of sight as the unrivaled means by which the New World might be understood. As they translate experiences of the New World into language, both writers record the power of olfactory perception to reflect memory and history, to shape identity, to mark unmistakably certain crisis moments of ethical action, and to delineate a form of knowledge crucial to their New World poetics of the novel. Observing and analyzing the olfactory language particular to the cultural spaces …

Direct Detection Of Homocysteine And Syntheses Of Lanthanide Complexes As Biosensors, Weihua Wang

LSU Doctoral Dissertations

At elevated levels, homocysteine (Hcy) is a risk factor for cardiovascular diseases and Alzheimer’s disease. It’s also implicated in a number of other diseases such as neural tube defects, pregnancy complications, and renal failures. The monitoring of Hcy levels in plasma is of current concern. To date, the biochemical mechanism by which Hcy is involved in disease states is unclear. Herein, we describe highly selective colorimetric methods for the direct determination of Hcy. Inexpensive, commercially available materials are reported. The results show potential application for the detection of Hcy in human blood plasma. Additionally, new HPLC postcolumn detection methods for …

Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy

LSU Doctoral Dissertations

A number of environmental stressors have been shown to interfere with reproductive and behavioral processes of fish by interfering with endocrine function. Most biomarkers of endocrine disturbance tend to be static measurements from dynamic systems making them difficult to evaluate within the context of an individual, or subtle effects that do not relate well to endpoints of ecological significance. I present an approach that uses a series of models, based on Atlantic croaker, to extrapolate laboratory results to indicators of individual and population health. First, I created a physiologically based model that simulates vitellogenesis in a female fish. The model …

Repression And Reduction: The Apparatchik's Discourse In The Works Of Ammianus Marcellinus, Denis Diderot, Victor Serge And George Orwell, Jason Paul Juneau

LSU Doctoral Dissertations

In monopolizing political power, the state claims to possess the best idea towards leading a society and solving its problems. While these claims may vary according to regime, all face the eventual failure of expectation on the part of its subjects. No regime can master all the variables in running the country, and so it must convince their subjects otherwise of its legitimacy, despite the reality of their failure. The apparatchik’s discourse is the interaction of the state’s discourse and that of its institutions. This discourse is used to uphold the state’s legitimacy through the expertise of its institutions. The …

Glycosylphosphatidylinositol-Anchored Proteins Are Required For Cell Wall Synthesis And Morphogenesis In Arabidopsis, C. Stewart Gillmor, Wolfgang Lukowitz, Ginger Brininstool, John C. Sedbrook, Thorsten Hamann, Patricia Poindexter, Chris Somerville

Faculty Publications

Mutations at five loci named PEANUT1-5 (PNT) were identified in a genetic screen for radially swollen embryo mutants, pnt1 cell walls showed decreased crystalline cellulose, increased pectins, and irregular and ectopic deposition of pectins, xyloglucans, and callose. Furthermore, pnt1 pollen is less viable than the wild type, and pnt1 embryos were delayed in morphogenesis and showed defects in shoot and root meristems. The PNT1 gene encodes the Arabidopsis thaliana homolog of mammalian PIG-M, an endoplasmic reticulum-localized mannosyltransferase that is required for synthesis of the glycosylphosphatidylinositol (GPI) anchor. All five pnt mutants showed strongly reduced accumulation of GPI-anchored proteins, suggesting that …

Mutation Of Sac1, An Arabidopsis Sac Domain Phosphoinositide Phosphatase, Causes Alterations In Cell Morphogenesis, Cell Wall Synthesis, And Actin Organization, Ruiqin Zhong, David H. Burk, C. Joseph Nairn, Alicia Wood-Jones, W. Herbert Morrison, Zheng Hua Ye

Faculty Publications

SAC (for suppressor of actin) domain proteins in yeast and animals have been shown to modulate the levels of phosphoinositides, thereby regulating several cellular activities such as signal transduction, actin cytoskeleton organization, and vesicle trafficking. Nine genes encoding SAC domain-containing proteins are present in the Arabidopsis thaliana genome, but their roles in plant cellular functions and plant growth and development have not been characterized. In this report, we demonstrate the essential roles of one of the Arabidopsis SAC domain proteins, AtSAC1, in plant cellular functions. Mutation of the AtSAC1 gene in the fragile fiber7 (fra7) mutant caused a dramatic decrease …

Detection Of Homocysteine And Cysteine, Weihua Wang, Oleksandr Rusin, Xiangyang Xu, Kyu Kwang Kim, Jorge O. Escobedo, Sayo O. Fakayode, Kristin A. Fletcher, Mark Lowry, Corin M. Schowalter, Candace M. Lawrence, Frank R. Fronczek, Isiah M. Warner, Robert M. Strongin

Faculty Publications

At elevated levels, homocysteine (Hcy, 1) is a risk factor for cardiovascular diseases, Alzheimer's disease, neural tube defects, and osteoporosis. Both 1 and cysteine (Cys, 3) are linked to neurotoxicity. The biochemical mechanisms by which 1 and 3 are involved in disease states are relatively unclear. Herein, we describe simple methods for detecting either Hey or Cys in the visible spectral region with the highest selectivity reported to date without using biochemical techniques or preparative separations. Simple methods and readily available reagents allow for the detection of Cys and Hey in the range of their physiologically relevant levels. New HPLC …

Host-Parasitoid Spatial Ecology: A Plea For A Landscape-Level Synthesis, James T. Cronin, John D. Reeve

Faculty Publications

A growing body of literature points to a large-scale research approach as essential for understanding population and community ecology. Many of our advances regarding the spatial ecology of predators and prey can be attributed to research with insect parasitoids and their hosts. In this review, we focus on the progress that has been made in the study of the movement and population dynamics of hosts and their parasitoids in heterogeneous landscapes, and how this research approach may be beneficial to pest management programs. To date, few studies have quantified prey and predator rates and ranges of dispersal and population dynamics …

Successful Island Reintroductions Of New Zealand Robins And Saddlebacks With Small Numbers Of Founders, Sabrina S. Taylor, Ian G. Jamieson, Doug P. Armstrong

Faculty Publications

Populations established with a small number of founders are thought to have a high risk of extinction due to Allee effects, demographic stochasticity, inbreeding and reduced genetic variation. We tested whether the initial number of birds released was related to persistence in reintroductions of saddlebacks (Philesturnus carunculatus) and robins (Petroica australis) to New Zealand offshore islands. Data were analysed for 31 populations that had been observed for at least 3 years since reintroductions. The numbers released ranged from 5-188. Most of the populations (26) survived and grew, including five from less than 15 founders, and four out of the five …

Lsu In The Eye Of The Storm: A University Model For Disaster Response, Renée Bacher, Teresa Devlin, Kristine Calongne, Joshua Duplechain, Stephanie Pertuit

LSU Press Published Books

No abstract provided.

Genetic Analysis Of The Sars-Coronavirus Spike Glycoprotein Functional Domains Involved In Cell-Surface Expression And Cell-To-Cell Fusion, Chad M. Petit, Jeffrey M. Melancon, Vladimir N. Chouljenko, Robin Colgrove, Michael Farzan, David M. Knipe, K. G. Kousoulas

Faculty Publications

The SARS-coronavirus (SARS-CoV) is the etiological agent of severe acute respiratory syndrome (SARS). The SARS-CoV spike (S) glycoprotein mediates membrane fusion events during virus entry and virus-induced cell-to-cell fusion. To delineate functional domains of the SARS-CoV S glycoprotein, single point mutations, cluster-to-lysine and cluster-to-alanine mutations, as well as carboxyl-terminal truncations were investigated in transient expression experiments. Mutagenesis of either the coiled-coil domain of the S glycoprotein amino terminal heptad repeat, the predicted fusion peptide, or an adjacent but distinct region, severely compromised S-mediated cell-to-cell fusion, while intracellular transport and cell-surface expression were not adversely affected. Surprisingly, a carboxyl-terminal truncation of …

Immunocytochemical Localization Of Small-Conductance, Calcium-Dependent Potassium Channels In Astrocytes Of The Rat Supraoptic Nucleus, William E. Armstrong, Adam Rubrum, Ryoichi Teruyama, Chris T. Bond, John P. Adelman

Faculty Publications

Supraoptic nucleus (SON) neurons possess a prominent afterhyperpolarization (AHP) that contributes to spike patterning. This AHP is probably underlain by a small-conductance, CA2+-dependent, K+ type 3 (SK3) channel. To determine the distribution of SK3 channels within the SON, we used immunocytochemistry in rats and in transgenic mice with a regulatory cassette on the SK3 gene, allowing regulated expression with dietary doxycycline (DOX). In rats and wild-type mice, SK3 immunostaining revealed an intense lacy network surrounding SON neurons, with weak staining in neuronal somata and dendrites. In untreated, conditional SK3 knockout mice, SK3 was overexpressed, but the pericellular pattern in the …

A Role For Airway Remodeling During Respiratory Syncytial Virus Infection, David Becnel, Dahui You, Joshua Erskin, Dawn M. Dimina, Stephania A. Cormier

Faculty Publications

Background: Severe respiratory syncytial virus infection (RSV) during infancy has been shown to be a major risk factor for the development of subsequent wheeze. However, the reasons for this link remain unclear. The objective of this research was to determine the consequences of early exposure to RSV and allergen in the development of subsequent airway hyperreactivity (AHR) using a developmental time point in the mouse that parallels that of the human neonate. Methods: Weanling mice were sensitized and challeged with ovalbumin (Ova) and/or infected with RSV. Eight days after the last allergen challenge, various pathophysiological endpoints were examined. Results: AHR …

F05rs Sgb No. 1 (Election Code Campaigning), Staples

Student Senate Enrolled Legislation

A BILL

To amend several portions of the Student Government Election Code concerning campaigning

Louisiana Agriculture Fall, 2005, Lsu Agcenter

Louisiana Agriculture

No abstract provided.

Hurricane-Forced Upwelling And Chlorophyll A Enhancement Within Cold-Core Cyclones In The Gulf Of Mexico, Nan D. Walker, Robert R. Leben, Shreekanth Balasubramanian

Faculty Publications

Clear skies, subsequent to Hurricane Ivan's passage across the Gulf of Mexico in September 2004, provided a unique opportunity to investigate upper ocean responses to a major hurricane. Oceanic cyclonic circulation was rapidly intensified by the hurricane's wind field (59-62 m s^-1), maximizing upwelling and surface cooling (3-7°C) in two large areas along Ivan's track. Upward isothermal displacements of 50-65 m, computed from wind stress and sea surface height changes, caused rapid ventilation of thermoclines and nutriclines, leading to phytoplankton blooms with peak concentrations 3-4 days later. Wind speed changes along Ivan's track demonstrated that the cool waters …

A Climate-Based Approach To The Restoration Of Fire-Dependent Ecosystems, Brian Beckage, William J. Platt, Bob Panko

Faculty Publications

Recurrent fires are integral to the function of many ecosystems worldwide. The management of fire-frequented ecosystems requires the application of fire at the appropriate frequency and seasonally, but establishing the natural fire regime for an ecosystem can be problematic. Historical records of fires are often not available, and surrogates for past fires may not exist. We suggest that the relationship between climate and fire can provide an alternative means for inferring past fire regimes in some ecosystems. © 2005 Society for Ecological Restoration International.

Status, Trends And Management Of Sturgeon And Paddlefish Fisheries, Ellen K. Pikitch, Phaedra Doukakis, Liz Lauck, Prosanta Chakrabarty, Daniel L. Erickson

Faculty Publications

The 27 extant species of sturgeons and paddlefishes (Order Acipenseriformes) represent a unique and relict lineage of fishes. Producers of coveted black caviar, sturgeons are one of the most valuable wildlife commodities on earth. The group is among the most endangered fishes with all species listed under Convention on International Trade in Endangered Species (CITES) Appendix I (two species) or II (25 species), only two species considered Lower Risk by IUCN, four of the nine US taxa and one Caspian species protected under the Endangered Species Act, and local extinctions recorded for 19 of 27 species. Despite their well-publicized imperilled …

Easy's Gettin' Harder All The Time: The Computational Theory And Affective States, Jason Megill, Jon Cogburn

Faculty Publications

We argue that A. Damasio's (1994) Somatic Marker hypothesis can explain why humans don't generally suffer from the frame problem, arguably the greatest obstacle facing the Computational Theory of Mind. This involves showing how humans with damaged emotional centers are best understood as actually suffering from the frame problem. We are then able to show that, paradoxically, these results provide evidence for the Computational Theory of Mind, and in addition call into question the very distinction between easy and hard problems in the contemporary philosophy of mind. © Blackwell Publishing Ltd. 2005.

Animal Virus Replication And Rnai-Mediated Antiviral Silencing In Caenorhabditis Elegans, R. Lu, M. Maduro, F. Li, H. W. Li, G. Broitman-Maduro, W. X. Li, S. W. Ding

Faculty Publications

The worm Caenorhabditis elegans is a model system for studying many aspects of biology, including host responses to bacterial pathogens, but it is not known to support replication of any virus. Plants and insects encode multiple Dicer enzymes that recognize distinct precursors of small RNAs and may act cooperatively. However, it is not known whether the single Dicer of worms and mammals is able to initiate the small RNA-guided RNA interference (RNAi) antiviral immunity as occurs in plants and insects. Here we show complete replication of the Flock house virus (FHV) bipartite, plus-strand RNA genome in C. elegans. We show …

Altering The Tropism Of Lentiviral Vectors Through Pseudotyping, James Cronin, Xian Yang Zhang, Jakob Reiser

Faculty Publications

The host range of retroviral vectors including lentiviral vectors can be expanded or altered by a process known as pseudotyping. Pseudotyped lentiviral vectors consist of vector particles bearing glycoproteins (GPs) derived from other enveloped viruses. Such particles possess the tropism of the virus from which the GP was derived. For example, to exploit the natural neural tropism of rabies virus, vectors designed to target the central nervous system have been pseudotyped using rabies virus-derived GPs. Among the first and still most widely used GPs for pseudotyping lentiviral vectors is the vesicular stomatitis virus GP (VSV-G), due to the very broad …