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The Edible Landscape: Plant Breeding, Farming, And Sustainbility In Northwest Portugal, Joseph Blanchard Powell Jan 2015

The Edible Landscape: Plant Breeding, Farming, And Sustainbility In Northwest Portugal, Joseph Blanchard Powell

LSU Doctoral Dissertations

This dissertation is an ethnographic analysis of a participatory plant breeding project in northwest Portugal. Participatory plant breeding (PPB) is a crop enhancement strategy that brings farmers and plant breeders together in the effort to conserve crop genetic resources in-situ, improve yield, and increase the overall agricultural sustainability in agriculture. One strategy in PPB calls for plant breeders to spend considerable time on working farms to understand better farmers’ knowledge and skill, and to survey the existing crop genetic diversity within the existing resource limitations on farms. Although there are clear social implications for PPB, the bulk of PPB evaluative …

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Development And Characterization Of A Live-Attenuated Vaccine To Combat Equine Herpesvirus Type-1 Infections, Shiliang Anthony Liu Jan 2015

Development And Characterization Of A Live-Attenuated Vaccine To Combat Equine Herpesvirus Type-1 Infections, Shiliang Anthony Liu

LSU Doctoral Dissertations

Equine Herpesvirus 1 (EHV-1) is an important ubiquitous enzootic equine pathogen and one of the most common pathogens of the horse, causing, respiratory disease, epidemic abortion, occasionally neurological disease in horses, which leads to significant economic losses to the horse industry. EHV-1 induces several clinical signs of disease ranging in severity, from mild respiratory disease to abortion in pregnant mares, neonatal foal death and neuropathogenic disorders. Natural EHV-1 infection stimulated short lived protective immunity and had both humoral and cellular immune responses. Currently vaccination remains the best option to prevent EHV-1 infection and different applications of vaccination have been investigated …

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Synthesis, Characterization, And Evaluation Of Small Molecule-Based Fluorogenic Probes For The Detection Of Cellular Thiols, Rasika Ranatunga Nawimanage Jan 2015

Synthesis, Characterization, And Evaluation Of Small Molecule-Based Fluorogenic Probes For The Detection Of Cellular Thiols, Rasika Ranatunga Nawimanage

LSU Doctoral Dissertations

Fluorescence methods for disease diagnosis and detection of important analytes are becoming popular route as a technique, as they offer a simple non-invasive approach. Recently, many novel fluorophores and probes have been reported for selectively and sensitively detecting low abundance biological species in disease pathways. Biological thiols, such as glutathione, cysteine, and homocysteine, along with the smallest member hydrogen sulfide, are key thiol analytes in biological environments, and they play a vital role in living systems by maintaining the redox homeostasis of cells. Alteration of their ratios can cause cellular dysfunction and cell death. Furthermore, thiol levels in cells and …

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"The Lonely Romantic": Nature, Education, And Cultural Pessimism In The Early Works Of Hermann Hesse, Erik Paul Wagner Jan 2015

"The Lonely Romantic": Nature, Education, And Cultural Pessimism In The Early Works Of Hermann Hesse, Erik Paul Wagner

LSU Master's Theses

This study examines the early works of Hermann Hesse in the historical context of early twentieth-century Germany. While Hesse’s literary career spans over six decades, most scholarship focuses only on a brief period. Historians study his Weimar novels, as psychologically penetrating pieces that offer insights into this fascinating and chaotic era of German history. Yet, Hesse’s early works have not received due attention in historical scholarship. This situation is unfortunate because Hesse’s prewar writings provide interesting and relevant commentary on life in fin de siècle Germany. Hesse’s early writings offer unique insights into aspects of German culture and society, specifically …

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Using Trace Fossils To Determine The Role Of Oceanic Anoxic Event Ii On The Cretaceous Western Interior Seaway Paleoenvironment, Jacob Frederick Grosskopf Jan 2015

Using Trace Fossils To Determine The Role Of Oceanic Anoxic Event Ii On The Cretaceous Western Interior Seaway Paleoenvironment, Jacob Frederick Grosskopf

LSU Doctoral Dissertations

Did well-oxygenated benthic conditions exist in all parts of the Cretaceous Western Interior Seaway (CWIS) during the deposition of Bed 63 at the onset Oceanic Anoxic Event II (OAE II), as suggested by findings from two cores from the central portion of the CWIS? This problem was approached by categorizing the bioturbation that is prevalent through Bed 63 into oxygen-related ichnofabrics (ORI) in order to describe benthic oxygen conditions. These data were collected from outcrop and core among seven different sites along West–East and North–South transects that traversed portions of the CWIS with differing depositional settings and proximities to the …

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Development Of A Three-Dimensional Bioprinter With Inline Light Activation For Bone Tissue Engineering, Colton Alexander Mcelheny Jan 2015

Development Of A Three-Dimensional Bioprinter With Inline Light Activation For Bone Tissue Engineering, Colton Alexander Mcelheny

LSU Master's Theses

Bioprinting offers exciting possibilities for tissue engineering related to tissue and organ failure due to trauma, disease, or aging. This is of substantial societal value as the world populace mean age rises. Current needs for tissue and organ repair far exceed availability. A strategy being explored to counter this imbalance is the single step fabrication of cellular constructs. This paper explores various bioprinting techniques and suggests a custom design for a cost-effective, low-maintenance bioprinting platform for academic research. The platform functionality was validated via two-dimensional image transfer and simple three-dimensional geometries.

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Increasing Student Engagement In The Secondary Math Classroom, Chantell Holloway Walker Jan 2015

Increasing Student Engagement In The Secondary Math Classroom, Chantell Holloway Walker

LSU Master's Theses

This thesis reports on a professional development package developed by the author to help three teachers increase the level of student engagement in their math classrooms. There were three phases: 1) initial presentation of strategies and sample lessons, 2) classroom implementation, 3) reflection and evaluation. As a result of the professional development, the Louisiana Compass Teacher Evaluation Rubric scores of the teachers improved in the area of student engagement. This thesis can be used as a guide for principals or instructional specialists who wish to provide professional development for small groups of teachers, with a focus on increasing student engagement.

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Regarding Suicide: A Textually Informed Rhetorical And Psychoanalytic Construct Of The State Of Disconstituency, Disconstitutive Rhetoric, And The Disconstituent As Related To The Constitutive Rhetorical Structure Of The Vanishing Subject, Charles Stowers Womelsdorf Jan 2015

Regarding Suicide: A Textually Informed Rhetorical And Psychoanalytic Construct Of The State Of Disconstituency, Disconstitutive Rhetoric, And The Disconstituent As Related To The Constitutive Rhetorical Structure Of The Vanishing Subject, Charles Stowers Womelsdorf

LSU Doctoral Dissertations

Suicide contagion is a real phenomenon. The stigmatization of suicide attempters, completers, survivors of suicide loss, and the idea of suicide itself is at least partly to blame for these outbreaks. Regarding suicide as an analyst, journalist, witness, responder, or bereaved family member or friend can be a devastating form of metaphorical and literal looking. Through a psychoanalytic understanding of constitutive rhetoric, this dissertation offers a textualized way of considering the difficult process of giving individuals who have completed suicide one’s regard. Beyond just suicide, this rhetoric of regard presents the disconstituent as the lost persona that withdraws from identification …

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Study Of Factors Affecting Growth And Development Of Narrow Brown Leaf Spot Of Rice Caused By Cercospora Janseana (Racib.) O. Const., Kirandeep Kaur Mani Jan 2015

Study Of Factors Affecting Growth And Development Of Narrow Brown Leaf Spot Of Rice Caused By Cercospora Janseana (Racib.) O. Const., Kirandeep Kaur Mani

LSU Doctoral Dissertations

Studies evaluated the effects of planting date, cultivar susceptibility, fungicide application timing, nitrogen management, and tillage practices on the severity of narrow brown leaf spot of rice (NBLS) caused by Cercospora janseana. All factors evaluated affected NBLS severity. The mid-April planted rice had less NBLS as compared to mid-May, late planted rice. Propiconazole fungicide (Tilt) application at panicle initiation or early boot stage was found equally effective in terms of disease reduction in mid-April planting while panicle initiation stage was the best time to apply fungicide in the late planting (mid-May). Early onset and higher severity of NBLS was observed …

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Effects Of Spinosad On Formosan Subterranean Termite, Coptotermes Formosanus Shiraki (Isoptera: Rhinotermitidae), Dependra Bhatta Jan 2015

Effects Of Spinosad On Formosan Subterranean Termite, Coptotermes Formosanus Shiraki (Isoptera: Rhinotermitidae), Dependra Bhatta

LSU Master's Theses

Formosan subterranean termites, Coptotermes formosanus, are economically important structural pests of warm and humid regions. Different control measures have been developed to avoid the damage caused by them. Among the available measures, chemical treatments have predominated for the last five decades. In our study we tested the effect of spinosad, a biopesticide, on C. formosanus. Spinosad is composed of bacterial metabolites that have been widely used to control various agriculture pests. It has been tested on Kalotermitidae and Termitidae; however, not on Rhinotermitidae, the most destructive of termite families. Both no choice and choice tests were conducted using three concentrations, …

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Factors Influencing Mottled Duck Nest Success On The Atchafalaya River Delta, Brendan Caillouet Jan 2015

Factors Influencing Mottled Duck Nest Success On The Atchafalaya River Delta, Brendan Caillouet

LSU Master's Theses

The Atchafalaya River Delta system along with the Wax Lake Outlet Delta and the Mississippi River Delta are the only three areas in Louisiana where land is being gained. Beneficial use of dredge spoil from shipping channel maintenance is used on the Atchafalaya River Delta to supplement natural accretion. These dredge spoil islands have the ability to provide valuable nesting habitat for a variety of waterbirds, including Mottled Ducks. Previous studies on these islands reported mammalian predation to be a significant cause of nest failure for Mottled Ducks. I tested the hypothesis that predator reduction through trapping would increase Mottled …

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Effects Of Detrital Subsidy On Arthropod Communities In Louisiana Rice Fields And Predation On Rice Water Weevil (Lissorhoptrus Oryzophilus), Nathan Mercer Jan 2015

Effects Of Detrital Subsidy On Arthropod Communities In Louisiana Rice Fields And Predation On Rice Water Weevil (Lissorhoptrus Oryzophilus), Nathan Mercer

LSU Master's Theses

The rice water weevil (RWW), Lissorhoptrus oryzophilus (Kuschel), is the most important insect pest of rice in the United States. Integrated pest management strategies for RWW in Louisiana consist of cultural controls, resistant cultivars and chemical insecticides. The fourth component of IPM, biological control, is largely absent from the literature for RWW, making exploration of biological control a logical next step in developing a full set of IPM strategies. The three main types of biological control are augmentation, classical and conservation. With little known about RWW predators, conservation biological control makes the most sense as local natural enemy abundance is …

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Investigations Into Ecogeomorphodynamics Of Coastal Embryo Dunes At Padre Island National Seashore, Texas, Katherine Anne Renken Jan 2015

Investigations Into Ecogeomorphodynamics Of Coastal Embryo Dunes At Padre Island National Seashore, Texas, Katherine Anne Renken

LSU Doctoral Dissertations

This dissertation is an investigation into the interplay between vegetation and aeolian processes in the coastal embryo dune environment at Padre Island National Seashore, Texas. Vegetation is a geomorphic agent, altering aeolian process dynamics. This research adopted a three-pronged approach to improving our understanding of ecogeomorphodynamics in the coastal environment. The first study analyzed large-scale spatiotemporal trends in the vegetation community of the embryo dune environment in order to contextualize smaller scale aeolian processes. Results of this study demonstrated that there was a clear transition in community assemblage from the seaward edge of the embryo dune zone, where species functioned …

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Motion Analysis Of Biotin Carboxylase-Driven Robotic Nano-Swimmers, Sima Hannani Jan 2015

Motion Analysis Of Biotin Carboxylase-Driven Robotic Nano-Swimmers, Sima Hannani

LSU Master's Theses

The purpose of this study is to experimentally validate the hypothesis that the enzyme biotin carboxylase (BC) can behave as a bimolecular motor and propel nano-scale particles in fluidic environments. This hypothesis was proposed in the M.S. thesis “Toward the Development of Biotin Carboxylase Driven Robotic Nano-swimmer” by Rachel Yates (Yates, 2012). In (Yates, 2012), the nano-particle (called a nano-swimmer) is a Janus particle with BC molecules attached to one hemisphere. The idea is that in the presence of its substrates (i.e., fuel) BC will cause individual nano-particles to undergo non-Brownian motion by virtue of its conformational change. In order …

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Polycyclic Aromatic Hydrocarbons Dynamics In The Northern Gulf Of Mexico, Puspa Lal Adhikari Jan 2015

Polycyclic Aromatic Hydrocarbons Dynamics In The Northern Gulf Of Mexico, Puspa Lal Adhikari

LSU Doctoral Dissertations

Polycyclic aromatic hydrocarbons (PAHs) are introduced into the marine environment via oil seeps/spills, riverine discharges, continental runoff, coastal erosion, and atmospheric deposition. An estimated 2.1 x 1010g of PAHs entered into the northern Gulf of Mexico (GOM) during the Deepwater Horizon (DWH) oil spill in 2010. It became evident following the oil spill that accurate quantification of ultimate fate of these potentially carcinogenic and/or mutagenic organic pollutants is extremely challenging. In general, very little is known about PAHs fate, distribution and accumulation in the open ocean ecosystems. This study determines the upper ocean vertical fluxes and sedimentary PAHs accumulation rates …

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This Is My Attempt To Hold On, Kimberly Reneé Jones Jan 2015

This Is My Attempt To Hold On, Kimberly Reneé Jones

LSU Master's Theses

I am an identical twin. The connection I share with my twin sister is intense and immediate. But now, we live over 800 miles apart. This Is My Attempt To Hold On serves as a visual metaphor for the longing for the undiluted rapport we have when we are together, and the frustrations of communicating with her through a digital device. I am constantly dissatisfied with my attempts to connect with her. I watch myself, my words, and my thoughts become diffused through the pixels. The work exists as composites of various mediums, creating a dialogue between photography, printmaking, sculpture, …

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My Choice, My Fraternity, And My Engagement: Experiences Of White Men In Black Greek Letter Organizations (Bglo), Kourtney Prentice Gray Jan 2015

My Choice, My Fraternity, And My Engagement: Experiences Of White Men In Black Greek Letter Organizations (Bglo), Kourtney Prentice Gray

LSU Doctoral Dissertations

This qualitative study grounded in the theoretical framework and research of Alexander Astin’s Student Engagement Theory, with support from Critical Race Theory and Terrell Strayhorn’s work on Sense of Student Belonging, utilizes a methodological case-study approach with multiple units of analysis. In an effort to understand the choice, ownership, and engagement of White men who hold membership in Black Greek Letter Organizations (BGLO), this study utilized the counter-narrative tenant presented and supported by Critical Race Theory to examine the racial identity and engagement of fraternity men from a pluralistic experience. Additionally, the researcher hypothesized that there is a special experience …

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Development Of Satellite-Assisted Forecasting System For Oyster Norovirus Outbreaks, Jiao Wang Jan 2015

Development Of Satellite-Assisted Forecasting System For Oyster Norovirus Outbreaks, Jiao Wang

LSU Doctoral Dissertations

Norovirus outbreaks can cause the closure of oyster harvesting waters and acute gastroenteritis in humans associated with consumption of contaminated raw oysters. The overall goal of this study was to develop a satellite-assisted forecasting system for oyster norovirus outbreaks. The forecasting system is comprised of three components: (1) satellite algorithms for retrieval of environmental variables, including salinity, temperature, and gage height, (2) an Artificial Neural Network (ANN) based model, called NORF model, for predicting relative risk levels of oyster norovirus outbreaks, and (3) a mapping method for visualizing spatial distributions of norovirus outbreak risks in oyster harvest areas along Louisiana …

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Excavations And Interpretation Of Two Ancient Maya Salt-Work Mounds, Paynes Creek National Park, Toledo District, Belize, Rachel Mariah Watson Jan 2015

Excavations And Interpretation Of Two Ancient Maya Salt-Work Mounds, Paynes Creek National Park, Toledo District, Belize, Rachel Mariah Watson

LSU Doctoral Dissertations

In 2012, excavations were conducted at Witz Nabb’ and Killer Bee the last remaining above sea level features Paynes Creek National Park, Belize. Salt is a basic biological necessity that was in limited supply at inland Maya cities. The ancient Maya of coastal Belize produced by fire enhanced evaporation of salt enriched brine. Survey and excavation at inundated salt works in a shallow lagoon in Paynes Creek National Park provide extensive evidence of this technique in the form of briquetage, the remains of pots used in the fire evaporation. Lacking is any evidence that the salinity of seawater was enriched …

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Nanoscale Gumbos: Size-Control, Characterization, And Applications As Enantioselective Molecularly Imprinted Polymers And Fluorescent Materials, Suzana Hamdan Jan 2015

Nanoscale Gumbos: Size-Control, Characterization, And Applications As Enantioselective Molecularly Imprinted Polymers And Fluorescent Materials, Suzana Hamdan

LSU Doctoral Dissertations

Nanomaterials derived from a group of uniform materials based on organic salts (GUMBOS) have been introduced into the scientific literature through many analytical, biological, and technological applications. These nanomaterials, referred to as nanoGUMBOS, have been shown to display a number of interesting properties including fluorescence, magnetism, tumor targeting, and optoelectronic properties. Herein, we present major studies on nanoGUMBOS including synthesis and size-control, chiral molecular imprinting in polymers, as well as investigation of optical properties and quantum yield of fluorescent semiconductor-based nanoGUMBOS. Various strategies were introduced for production of well-defined nanoGUMBOS. Specifically, several methods based on sonochemistry, microwave, cyclodextrin, and surfactant-assisted …

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Integrated Multiple-Tactic Management Of The Redbanded Stink Bug On Soybeans In Louisiana, Miyanda Nzala Moonga Jan 2015

Integrated Multiple-Tactic Management Of The Redbanded Stink Bug On Soybeans In Louisiana, Miyanda Nzala Moonga

LSU Doctoral Dissertations

Stink bugs (Hemiptera: Pentatomidae) are major pests of soybeans in Louisiana and heavy infestations often lead to economic losses. The stink bug species complex has changed in the past decade with the prevalence of the invasive redbanded stink bug, Piezodorus guildinii (Westwood), which causes greater damage than other stink bug species. Moreover, control of the redbanded stink bug has been faced with challenges because it is less sensitive to recommended insecticides. Therefore, studies were conducted to evaluate different control options for P. guildinii. Among the studies conducted was the current status of egg parasitoids of stink bugs in Louisiana. Telenomus …

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Transmembrane Signaling And Conformational Regulation Of Integrin, Ping Hu Jan 2015

Transmembrane Signaling And Conformational Regulation Of Integrin, Ping Hu

LSU Doctoral Dissertations

Integrins are heterodimeric cell adhesion molecules that play an essential role in hemostasis, thrombosis, cell migration, and can transmit bidirectional signals. The inside-out activating signal triggers integrin conformational change, leading to high affinity for extracellular ligands. Binding of extracellular matrix ligands to integrins results in outside-in signaling that leads to formation of focal adhesion (FA) complex at the integrin cytoplasmic tails and activation of downstream signal pathways. Transmembrane/cytoplasmic domains are hypothesized to associate in resting integrins, whereas ligand binding and intracellular activating signals induce transmembrane domain separation. However, how this conformational change affects integrin outside-in signaling and whether the á …

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Holocene Palynology Of The Gulf Of Papua, Papua New Guinea: Using Modern Palynomorph Distribution To Better Constrain Paleoenvironmental Changes, Marie Louise Thomas Jan 2015

Holocene Palynology Of The Gulf Of Papua, Papua New Guinea: Using Modern Palynomorph Distribution To Better Constrain Paleoenvironmental Changes, Marie Louise Thomas

LSU Doctoral Dissertations

Multiple NSF (National Science Foundation)-funded MARGINS Source-to-Sink cruises were conducted in the Gulf of Papua (GoP), Papua New Guinea (PNG), from 2003 through 2005 to better understand how sediment is created, transported, and deposited. Although much work has been done on the data collected during these cruises, palynological analysis has never been conducted on the hundreds of available cores. The first phase of this project (Chapters 2 and 3) examines the connection between modern depositional regimes in the GoP and species assemblages recovered. Statistical analysis of palynomaceral assemblages (Chapter 2) indicates a correlation between their distribution and bathymetry, sedimentation rate, …

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Effects Of Inbreeding On Endangered Red Wolves (Canis Rufus), Kristin E. Brzeski Jan 2015

Effects Of Inbreeding On Endangered Red Wolves (Canis Rufus), Kristin E. Brzeski

LSU Doctoral Dissertations

Inbreeding depression, the reduction in offspring fitness caused by mating among close relatives, is widespread in small populations and a major concern in conservation biology because it can affect population persistence. The negative effects of inbreeding results in the evolution of inbreeding avoidance behaviors; within small populations, such behaviors may encourage individuals to select mates outside of their respective species. Mate choice may also be facilitated by variation at major histocompatibility complex (MHC) genes, a gene group critical for immune response and disease resistance. Given broad impacts of inbreeding and MHC variation on fitness and behavior, evaluating their effects is …

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Shallow Water Depth Inversion Based On Data Mining Models, Shu Gao Jan 2015

Shallow Water Depth Inversion Based On Data Mining Models, Shu Gao

LSU Master's Theses

This thesis focuses on applying machine-learning algorithms on water depth inversion from remote sensing images, with a case study in Michigan lake area. The goal is to assess the use of the public available Landsat images on shallow water depth inversion. Firstly, ICESAT elevation data were used to determine the absolute water surface elevation. Airborne bathymetry Lidar data provide systematic measure of water bottom elevation. Subtracting water bottom elevation from water surface elevation will result in water depth. Water depth is associated with reflectance recorded as DN value in Landsat images. Water depth inversion was tested on ANN models, SVM …

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The Effect Of Frequent Quizzing On Student Populations With Differing Preparation And Motivation In The High School Biology Classroom, Rebecca Lynn Kling Achord Jan 2015

The Effect Of Frequent Quizzing On Student Populations With Differing Preparation And Motivation In The High School Biology Classroom, Rebecca Lynn Kling Achord

LSU Master's Theses

This study was undertaken to test whether frequent quizzing would have different learning outcomes with the different populations within the classroom. Normalized mean learning gains were compared among classes that were quizzed or not quizzed. Allied Health Honors, Allied Health Academic and Academic classes in a high school biology classroom were given pre- and posttests in three units of study: protein synthesis, genetics, and classification. The same student population was also analyzed based on academic achievement levels: high, medium and low. In each unit, the experimental group was taught with traditional power point based lectures and guided notes, laboratories, activities, …

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Exploration Of Segmented Flow In Microchannels Using The Volume Of Fluid Method In Ansys Fluent, Jace Michael Boudreaux Jan 2015

Exploration Of Segmented Flow In Microchannels Using The Volume Of Fluid Method In Ansys Fluent, Jace Michael Boudreaux

LSU Master's Theses

Segmented flow can be utilized in lab-on-a-chip technologies to speed up chemical and biological analysis. Segmented flow (also known as Taylor flow or the Bretherton problem) has often been explored in circular channels, but rectangular channels are more common for microfluidics applications. To this end, pressure-driven droplet flow in a square microchannel is studied using the volume of fluid method in ANSYS Fluent, a computational fluid dynamics program. It was found that for low Reynolds number (Ret = 0.01) and droplet sizes larger than the channel diameter, the flow is mostly influenced by capillary number and viscosity ratio. The …

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Factors Influencing Sustainable Cocoa Production In Northern Haiti, Wegbert Chery Jan 2015

Factors Influencing Sustainable Cocoa Production In Northern Haiti, Wegbert Chery

LSU Master's Theses

Given the environmental concerns on the one hand, especially soil erosion and deforestation, and the hope that the global cocoa market offers on the other hand, cocoa production is a potential candidate to simultaneously guarantee a competitive return to investment for farmers in northern Haiti and mitigate the negative environmental impact of farming practices. It becomes crucial for policy makers and investors to know and understand the key elements of the decision to produce cocoa. Though there has been substantial effort to improve the cocoa sector in Haiti, cocoa production systems in Haiti lag behind in the area of sustainability. …

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Neodymium Isotope Ratios And A Positive Δ13c Excursion: Connecting Oceanographic And Climate Changes Near The M4-M5 Sequence Boundary Of The Late Ordovician, Zachary Wright Jan 2015

Neodymium Isotope Ratios And A Positive Δ13c Excursion: Connecting Oceanographic And Climate Changes Near The M4-M5 Sequence Boundary Of The Late Ordovician, Zachary Wright

LSU Master's Theses

A significant positive carbon isotope excursion first described from the Guttenberg Member of the Decorah Formation in Iowa called the GICE is a defining feature of Late Ordovician chemostratigraphy. It occurs near the M4-M5 sequence boundary of the Late Ordovician and has been correlated across the globe using prominent K-bentonite ash beds and conodont biomarkers. The cause of the GICE has been debated, with some arguing that it represents the initiation of a glacial period in a greenhouse climate 10 Ma before the end Ordovician glaciation and extinction. A variety of cooling signals have been identified across the M4-M5 sequence …

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Genomic Diversification In Strains Of Rickettsia Felis Isolated From Different Arthropods, Joseph J. Gillespie, Timothy P. Drisco, Victoria I. Verhoeve, Tadanobu Utsuki, Claudia Husseneder, Vladimir N. Chouljenko, Abdu F. Azad, Kevin R. Macaluso Dec 2014

Genomic Diversification In Strains Of Rickettsia Felis Isolated From Different Arthropods, Joseph J. Gillespie, Timothy P. Drisco, Victoria I. Verhoeve, Tadanobu Utsuki, Claudia Husseneder, Vladimir N. Chouljenko, Abdu F. Azad, Kevin R. Macaluso

Faculty Publications

Rickettsia felis (Alphaproteobacteria: Rickettsiales) is the causative agent of an emerging flea-borne rickettsiosis with worldwide occurrence. Originally described from the cat flea, Ctenocephalides felis, recent reports have identified R. felis from other flea species, as well as other insects and ticks. This diverse host range for R. felis may indicate an underlying genetic variability associated with host-specific strains. Accordingly, to determine a potential genetic basis for host specialization, we sequenced the genome of R. felis str. LSU-Lb, which is an obligate mutualist of the parthenogenic booklouse Liposcelis bostrychophila (Insecta: Psocoptera). We also sequenced the genome of R. felis str. LSU, …

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