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Nitrogen Biogeochemistry In A Restored Mississippi River Delta: A Modeling Approach, Benjamin Lee Branoff Jan 2012

Nitrogen Biogeochemistry In A Restored Mississippi River Delta: A Modeling Approach, Benjamin Lee Branoff

LSU Master's Theses

There is evidence that significant reductions (about 50%) in surface water nitrate concentrations within coastal deltaic wetlands receiving diverted Mississippi River water can be contributed to denitrification. Yet there is also contrasting evidence that other processes could be responsible for this nitrate reduction. As Louisiana plans the implementation of major Mississippi River sediment diversions, a thorough understanding of nitrogen dynamics is necessary to reduce risks of coastal eutrophication and offshore hypoxia. A mechanistic numerical computer model has been developed to simulate nitrogen biogeochemistry within the wetlands of the prograding Wax Lake Delta. This model is calibrated to observed fluxes within …

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Oyster Reef Restoration In The Northern Gulf Of Mexico: Effect Of Substrate And Age On Ecosystem Services, Laura Alicia Brown Jan 2012

Oyster Reef Restoration In The Northern Gulf Of Mexico: Effect Of Substrate And Age On Ecosystem Services, Laura Alicia Brown

LSU Master's Theses

Oyster reefs provide estuaries with ecosystem services including carbon sequestration, shoreline stabilization, refugia for invertebrate biodiversity, and fisheries enhancement, but have been disappearing over the past century due to increasing overharvesting, disease, and eutrophication. The northern Gulf of Mexico has over 400 artificial oyster reefs constructed of various materials created through efforts to restore ecosystem services lost with declining oyster populations. The purpose of this study was to determine how two common artificial reef construction materials (rock vs. oyster shell) at various ages affect ecosystem services, specifically blue crab abundance, the commensal community, and oyster recruitment, as well as to …

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An Extensible And Scalable Pilot-Mapreduce Framework For Data Intensive Applications On Distributed Cyberinfrastructure, Pradeep Kumar Mantha Jan 2012

An Extensible And Scalable Pilot-Mapreduce Framework For Data Intensive Applications On Distributed Cyberinfrastructure, Pradeep Kumar Mantha

LSU Master's Theses

The volume and complexity of data that must be analyzed in scientific applications is increasing exponentially. Often, this data is distributed; thus, the ability to analyze data by localizing it will yield limited returns. Therefore, an efficient processing of large distributed datasets is required, whilst ideally not introducing fundamentally new programming models or methods. For example, extending MapReduce - a proven effective programming model for processing large datasets, to work more effectively on distributed data and on different infrastructure (such as non-Hadoop, general-purpose clusters) is desirable. We posit that this can be achieved with an effective and efficient runtime environment …

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Lentiviral Transduction Of Epigenetically Modified Bovine Adult Stem Cells, Meredith Kathleen Addison Jan 2012

Lentiviral Transduction Of Epigenetically Modified Bovine Adult Stem Cells, Meredith Kathleen Addison

LSU Master's Theses

Bovine adipose-derived stem cells (ADS), a form of adult stem cells, are somatic cells that have similar characteristics of embryonic stem (ES) cells. Bovine ADS cells possess multipotent capabilities and have been found to express pluripotency genes associated with ES cells. The unique properties of ADS cells make them a desirable source for reprogramming experiments. The goal of reprogramming experiments is to transform somatic cells from a differentiated state to a pluripotent state. When somatic cells reprogram, there are certain epigenetic changes or modifications that must occur in order to successfully reprogram the nucleus. Epigenetic modifications will change the chromatin …

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Towards The Development Of Biotin Carboxylase Driven Robotic Nanoswimmers, Rachel Yates Jan 2012

Towards The Development Of Biotin Carboxylase Driven Robotic Nanoswimmers, Rachel Yates

LSU Master's Theses

The objective of this research is to take the first step towards demonstrating the use of the enzyme biotin carboxylase (BC) as a biomolecular motor. BC is a homodimeric protein involved in fatty biosynthesis in all organisms. The conjecture is that BC can convert chemical energy into useful mechanical work via its conformation change, which acts as a fin or flexible oar producing nonreciprocal motion. To this end, we fabricate a proof-of-concept biomolecular machine driven by BC molecules, viz., a robotic nanoswimmer. This machine consists of a Janus-type nanosize silica particle, where one hemisphere is coated with an intermediate layer …

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Juvenile Justice In Louisiana: An Exploratory Study Of Trends Surrounding Juvenile Incarceration, Sabrina Michelle Whitney Jan 2012

Juvenile Justice In Louisiana: An Exploratory Study Of Trends Surrounding Juvenile Incarceration, Sabrina Michelle Whitney

LSU Master's Theses

In the State of Louisiana, one of the major problems surrounding youth is juvenile delinquency. Several studies have been conducted regarding juvenile delinquency, however, actual research pertaining to recidivism among youth offenders who were later incarcerated as an adult vs. those who were not incarcerated as an adult are limited. For this study, chi-square analyses were conducted to analyze the association between six variables and recidivism. The age of first OJJ contact was the only variable that was not statistically significant. Such knowledge is crucial for research and policy formation at the local, state, and national levels for positive progression …

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Morphology Controlled Coating Of Catalytically Active Gold Structures Within Flow-Focused Millifluidic Reactor, Chelliah V. Navin Jan 2012

Morphology Controlled Coating Of Catalytically Active Gold Structures Within Flow-Focused Millifluidic Reactor, Chelliah V. Navin

LSU Master's Theses

Synthesis of micro/nanomaterials within confined flow-based systems such as microfluidics has always been a promising research. However, the inability to scale up reagent volumes due to geometric constraints and pressure development within the channels at higher flow rates has limited their usage. In recent times, millifluidics has emerged as a useful technique where, apart from the synthesis, the in situ characterization of materials becomes easier. In this study, formation of morphology-controlled gold structures at different time intervals (viz. 1, 5, and 9 h) within a millifluidic chip reactor was investigated using gold chloride and dimercaptosuccinic acid (DMSA) as precursor reagents …

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Oysters And Catfish: Resource Exploitation At Rollins Shell Ring, Ft. George Island, Florida, Julie Ann Doucet Jan 2012

Oysters And Catfish: Resource Exploitation At Rollins Shell Ring, Ft. George Island, Florida, Julie Ann Doucet

LSU Master's Theses

Detailed faunal analyses were conducted on two major subsistence resources, oysters and marine catfish, at Rollins Shell Ring, a Late Archaic (5000 – 3000 B.P.) site on the northeast coast of Florida. The focus of this investigation was on resource exploitation, and, specifically, whether there was evidence that oysters from this site were over-exploited. Three units from previous excavations at the site were selected for analysis, and represent the span of occupation recorded for this site. Measurements were obtained from oysters to determine habitat, and, along with shell height, were compared across time for any changes in the pattern of …

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Programming And Healing Temperature Effects On The Efficiency Of Confined Self-Healing Polymers, Yves Quentin Yougoubare Jan 2012

Programming And Healing Temperature Effects On The Efficiency Of Confined Self-Healing Polymers, Yves Quentin Yougoubare

LSU Master's Theses

Shape memory polymers are smart materials capable of fixing a temporary shape and returning to their initial shape in response to an external stimulus. Since the discovery and acknowledgment of their importance in 1960s, shape memory polymers have been the subject of tremendous and continuous attention. In a previous study conducted on a biomimetic shape memory polymer (SMP), the ability of a self-healing composite to heal, and to repair and restore structural-length scale damage using a close-then-heal (CTH) self-healing mechanism was examined and validated. The present study is purposed with investigation of the effects on healing efficiencies of the variation …

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Comparison Of Alumni Donors And Alumni Nondonors On Selected Demographic, Educational And Involvement Factors, Arlette Barbara Rodriguez Rodrigue Jan 2012

Comparison Of Alumni Donors And Alumni Nondonors On Selected Demographic, Educational And Involvement Factors, Arlette Barbara Rodriguez Rodrigue

LSU Doctoral Dissertations

This study compared College of Agriculture (COA) alumni of a research university (RU/VH) in the Southern U.S. on selected demographic characteristics and contact information by whether or not the alumni are donors to the university. The target population was COA graduates from 1862 Land Grant Universities located in the Southern portion of the United States. The accessible population was Louisiana State University (LSU) COA alumni graduates. The sample was alumni who completed their degree program from the years 1950 through 2000. The instrument used was the Tiger Advancement Information Lookup System (TAILS) database. Universities have become burdened by financial instability …

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Linking Nitrogen Biogeochemistry To Different Stages Of Wetland Soil Development In The Mississippi River Delta, Louisiana, Kelly Marie Henry Jan 2012

Linking Nitrogen Biogeochemistry To Different Stages Of Wetland Soil Development In The Mississippi River Delta, Louisiana, Kelly Marie Henry

LSU Doctoral Dissertations

Extensive wetland loss and nutrient-enhanced eutrophication occur across the Mississippi River delta and include newly emergent landscapes, in the early stages of ecological succession, and older landscape formations, with fully developed ecological communities. Here I tested how the anthropogenic effects of a climate-induced vegetation shift, an oil spill, and nitrate-enrichment regulate the principal environmental factors controlling nutrient biogeochemistry in wetland soils at different stages of development throughout the Mississippi River delta. In the older, transgressing Barataria basin, there was no clear effect of the climate-induced species shift from Spartina alterniflora Loisel to Avicennia germinans L. on soil nutrient chemistry. Observed …

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The Effect Of Loving Kindness Meditation And Student Teachers Stress And Empathy, Imre Csaszar Jan 2012

The Effect Of Loving Kindness Meditation And Student Teachers Stress And Empathy, Imre Csaszar

LSU Doctoral Dissertations

Teachers face increasing demands in the twenty-first century as they engage with students, administrators, coworkers, staff, and parents. High demands and stressors may generate feelings of emotional exhaustion in educators. If left ignored or untreated the emotional exhaustion may eventually lead to burnout and impairment. This prospectus highlights a study designed to explore a preventative option to mitigate the experience of stress felt by student teachers through a structured, guided mindfulness training practice: loving kindness meditation.

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Geometrical And Electronic Structure Of Metal Oxide Nanoparticles On Silica And Alumina, Udaya Indike Rodrigo Jan 2012

Geometrical And Electronic Structure Of Metal Oxide Nanoparticles On Silica And Alumina, Udaya Indike Rodrigo

LSU Doctoral Dissertations

Recent studies demonstrated nanometer-scale combustion-generated nanoparticles cause demonstrable health effects. It is essential to understand the chemical characteristics of these nanoparticles. Since combustion-generated nanoparticles arise in complex mixtures, we employed a dendrimeric method to generate simpler, more reproducible nanoparticles, which were tethered to fumed silica and alumina to provide surrogates for fly ash. We collected XANES and EXAFS data, which are useful for characterizing disordered mixtures where the metal is a minor component. The effect of particle size on structural properties was studied with copper oxide nanoparticles on fumed silica. XANES data demonstrated copper atoms in the nanoparticles are present …

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Developing A Geospatial Protocol For Coral Epizootiology, Jennifer Anne Lentz Jan 2012

Developing A Geospatial Protocol For Coral Epizootiology, Jennifer Anne Lentz

LSU Doctoral Dissertations

This dissertation explores how geographic information systems (GIS) and spatial statistics, specifically the techniques used to map, detect, and spatially analyze disease epidemics, could be used to advance our understanding of coral reef health. Given that different types of spatial analysis, as well as different parameter settings within each analysis, can produce noticeably different results, poor selection or improper use of a given technique would likely lead to inaccurate representations of the spatial distribution and false interpretations of the disease. For this reason, I performed a comprehensive review of the following types of exploratory spatial data analysis (ESDA): mapping and …

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Effect Of Instructional Methodologies On Student Achievement Modeling Instruction Vs. Traditional Instruction, Jacqueline Grace Barker Jan 2012

Effect Of Instructional Methodologies On Student Achievement Modeling Instruction Vs. Traditional Instruction, Jacqueline Grace Barker

LSU Master's Theses

ABSTRACT Different teaching styles can impact student learning in many ways. The purpose of this study was to determine the effectiveness of Modeling Instruction on student achievement in a high school Chemistry course. Different tests were used to compare the data at the beginning of a school year and at the end of the school year. The tests used were to determine gains in chemistry content knowledge, abilities to reason scientifically, and attitudes about learning chemistry. The control group was taught by traditional instruction through the use of lecture, note-taking, and textbook guided assignments. The experimental group was taught by …

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Modeling Gopher Tortoise (Gopherus Polyphemus) Habitat In A Fire-Dependnent Ecosystem In North Florida, Christina Legleu Jan 2012

Modeling Gopher Tortoise (Gopherus Polyphemus) Habitat In A Fire-Dependnent Ecosystem In North Florida, Christina Legleu

LSU Master's Theses

Gopher tortoise (Gopherus polyphemus) populations have declined with longleaf pine (Pinus palustris) ecosystems across their historic range. The influence of gopher tortoise burrows on co-inhabiting plants and animals necessitates an understanding of how landscape features and management practices influence gopher tortoise presence, absence, and abandonment. In this study, naïve gopher tortoise burrow encounter rates from a line transect distance sampling (LTDS) pilot study were used for two methods of modeling gopher tortoise habitat. In Chapter 1, naïve encounter rates were tested for a linear correlation to a HSI model created from three ranked geographic information system (GIS) landscape variables. Initial …

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Base-Caged Adenosine Triphosphate As A Model System For Photoactivatable Small Interfering Rna, Amanda Yoesting Hendrix Jan 2012

Base-Caged Adenosine Triphosphate As A Model System For Photoactivatable Small Interfering Rna, Amanda Yoesting Hendrix

LSU Master's Theses

Photocaged adenosine triphosphate (ATP) is one of the earliest examples of exerting spatial-temporal control over the activity of a substrate. The activity of ATP is blocked until near-ultraviolet light exposure photocleaves the cage moiety. Caged ATP has been used for a myriad of applications including kinetic studies of ATP-dependent enzymes. Traditional caging of ATP occurs at the gamma-phosphate, which has been found to competitively inhibit several enzymatic systems. It was hypothesized that blocking access to the adenosine N6 position via cage molecule would prevent the initial enzyme-substrate binding event from occurring prior to photolysis, effectively minimizing competitive inhibition. Utilizing a …

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Insights Into The Role Of Pfkfb3 In Cancer, Minsuh Seo Jan 2012

Insights Into The Role Of Pfkfb3 In Cancer, Minsuh Seo

LSU Doctoral Dissertations

PFKFB3, an isoform of PFK-2, which is highly expressed in cancer cells, has been suggested to be associated with enhanced aerobic glycolysis in cancer by elevating the intracellular levels of key glycolytic activator, Fru-2,6-P2. This work describes the importance of PFKFB3 function in metabolic alterations and adaptations of cancers, providing new insights into the PFKFB3-associated ROS regulation in cancer and suggesting promising strategies for cancer drug development. The first study investigates the therapeutic potential of novel PFKFB3 inhibitors as well as the molecular mechanism of PFKFB3 inhibition. I was able to identify small molecular inhibitors, N4A and YN1, which almost …

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Unraveling Ecological Effects On Social Behavior. Insights From Tent-Roosting Bats, Maria Sagot Jan 2012

Unraveling Ecological Effects On Social Behavior. Insights From Tent-Roosting Bats, Maria Sagot

LSU Doctoral Dissertations

Although group living has been associated with high fitness cost, multiple lines of evidence have suggested that it has evolved multiple times independently. Given the wide diversity of social systems, it appears that multiple explanations are necessary to understand this process. Although evidence indicates that multiple ecological and environmental factors might promote variation in cohesion of social organisms, studies investigating how these factors interrelate and shape social structure have been limited. In the tropics, there are at least 23 bat species that roost in modified structures called tents. These species present a wide diversity in social systems. Moreover, they have …

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Synthesis And Characterization Of Red And Near-Infrared Bodipy-Based Fluorophores For Various Biological Applications, Timsy Kaur Uppal Jan 2012

Synthesis And Characterization Of Red And Near-Infrared Bodipy-Based Fluorophores For Various Biological Applications, Timsy Kaur Uppal

LSU Doctoral Dissertations

ABSTRACT 4,4-Difluoro-3a,4a-diaza-s-indacene, better known as BODIPY® dyes, have attracted considerable attention due to their intriguing physicochemical and spectral properties, including high absorption coefficient, fluorescence quantum yield and good photochemical stability. Despite the recent progress achieved in this field, the synthesis of BODIPY derivatives that absorb and emit in the red- and NIR-region of the electromagnetic spectrum and their application to biomolecular targets, represents a long-standing challenge in BODIPY chemistry. This research work is therefore focused on the synthesis and characterization of red and NIR-emissive BODIPY-based fluorophores for various bioanalytical and biomedical applications. Chapter 1 of this dissertation represents a concise …

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Amd&Art: Performativity And Participation In Ecological Remediation, Travis Paine Brisini Jan 2012

Amd&Art: Performativity And Participation In Ecological Remediation, Travis Paine Brisini

LSU Doctoral Dissertations

In this study, I examine and theorize AMD&ART, an artwork devoted to treating polluted water in Vintondale, PA. AMD&ART is much more than simply a water treatment facility, however. Each chapter of this document examines AMD&ART through the lens of a different body of scholarly literature: the literature associated with land art, Systems Theory, Network Theory, Companion Specieshood and others. The theoretical focus of this paper is the emergent importance of the concept of performativity—“that reiterative power of discourse to produce the phenomena that it regulates and constrains” (Butler, Bodies 2)—in the deconstruction of the binary division of “nature” and …

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How Core Symptoms Of Autism Spectrum Disorder Predict Engagement In Specific Topographies Of Challenging Behavior, Sara Mahan Jan 2012

How Core Symptoms Of Autism Spectrum Disorder Predict Engagement In Specific Topographies Of Challenging Behavior, Sara Mahan

LSU Doctoral Dissertations

Challenging behavior, such as aggression, destructive behavior, and self-injurious behavior (SIB), are common among people of all ages with Autism Spectrum Disorder (ASD). Numerous researchers have found that greater severity of ASD or a diagnosis of ASD is significantly correlated with greater levels of challenging behavior. However, there is dearth of information on how core symptoms of ASD (i.e., socialization deficits, communication deficits, stereotypies) predict the engagement of specific topographies of challenging behavior above and beyond other variables, such as developmental functioning. The purpose of this study is to extend the current literature base through examining how core symptoms of …

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An Examination Of The Relationship Between Autism Spectrum Disorder, Intellectual Functioning, And Social Skills In Children, Kimberly Tureck Jan 2012

An Examination Of The Relationship Between Autism Spectrum Disorder, Intellectual Functioning, And Social Skills In Children, Kimberly Tureck

LSU Master's Theses

Autism spectrum disorders (ASD) are the focus of a vast amount of research due to their recent rise in prevalence. Nonetheless, there is a dearth of research looking at how ASD and IQ scores impact social skills. The present study aimed to extend the literature in this area by evaluating how ASD and IQ scores are related to ratings on a measure of appropriate and inappropriate social skills. Two groups of individuals participated: children without ASD and children with ASD. Two dependent measures of social skills (adaptive/appropriate social skills and hostile/inappropriately assertive social skills) were obtained using the Matson Evaluation …

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The Effects Of Coping Strategies On Burden Among Louisiana Alzheimer's Disease Caregivers, Rhonda Lee Jordan Jan 2012

The Effects Of Coping Strategies On Burden Among Louisiana Alzheimer's Disease Caregivers, Rhonda Lee Jordan

LSU Master's Theses

The purpose of this study was to examine the relationship between three coping strategies—emotion-focused, task-focused, and avoidance-focused—and the perceived burden among Louisiana Alzheimer’s disease caregivers. This study was a secondary data analysis. The target population was Alzheimer’s disease caregivers in Louisiana. The design for this study was cross-sectional. The instrument was a survey consisting of a demographic section, the Revised Memory and Behavior Problems Checklist, the shortened Zarit Burden Interview, and the Coping in Task questionnaire. Most caregivers reported engaging in task-focused coping. Emotion-focused coping and avoidance-focused coping were positively related to burden. No significant relationship existed between task-focused coping …

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Children's Representations Of Parenting Behaviors, Basic Negative Emotions, And Negative Self-Conscious Emotions In The Narrative Story Stem Technique, Loredana Apavaloaie Jan 2012

Children's Representations Of Parenting Behaviors, Basic Negative Emotions, And Negative Self-Conscious Emotions In The Narrative Story Stem Technique, Loredana Apavaloaie

LSU Doctoral Dissertations

The current study examined middle childhood aged Romanian children’s representations of parenting behaviors, basic negative emotions, and negative self-conscious emotions in the Narrative Story Stem Technique (NSST; Bretherton, Ridgeway, & Cassidy, 1990). More specifically, the research objectives of the study were a) to identify the frequency of the representations that were reflected in children’s narratives, b) to identify the specific stories that elicited the greatest number of representations, c) to identify possible relationships among children’s representations, their age, and amount of time that parents spend with their children, d) to identify gender differences in representations, and e) to evaluate the …

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Single-Molecule Detection Of Molecular Beacons Generated From Ldr On Thermoplastic Microfluidic Device For Bioanalysis, Zhiyong Peng Jan 2012

Single-Molecule Detection Of Molecular Beacons Generated From Ldr On Thermoplastic Microfluidic Device For Bioanalysis, Zhiyong Peng

LSU Doctoral Dissertations

Current clinical techniques for nucleic acid detection and analysis often involve PCR, lacking adequate specificity or sensitivity to meet the stringent requirements in certain applications. This research aims to develop an innovative molecular assay and the associated hardware to rapidly signal the presence of certain targets using reporter sequence found in their genome without requiring PCR. This assay coupled the sensitivity of single-pair fluorescence resonance energy transfer (spFRET) with the specificity of ligase detection reaction (LDR) to provide near real-time readout of target biomarkers. Heightened concerns on potential bioterrorism threats, such as rapid dissemination of pathogenic bacteria or viruses into …

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The Utilization Of Chemical Communication By Three Species Of Ghost Shrimp, Callichirus Islagrande, Callichirus Major, And Lepidophthalmus Louisianensis, And The Transport Of Chemical Cues Within And Between Burrows, Julie Emily Prerost Jan 2012

The Utilization Of Chemical Communication By Three Species Of Ghost Shrimp, Callichirus Islagrande, Callichirus Major, And Lepidophthalmus Louisianensis, And The Transport Of Chemical Cues Within And Between Burrows, Julie Emily Prerost

LSU Doctoral Dissertations

A multidisciplinary study of the factors affecting the potential use of chemical cues by three species of infaunal shrimp was performed in three parts. A set of modified y-maze choice experiments were performed to establish the ability of three species of ghost shrimp, Callichirus islangrande, Callichirus major, and Leptidophthalmus louisianensis, to detect conspecifics via chemical cue. The time budgets for the detection of conspecifics chemical cues differed significantly from controls (no cue) for both animal cues and odor only cues indicating that all three species were able to detect the difference in sex of conspecific chemical cues regardless of cue …

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Nitrogen And Carbon Export To The Gulf Of Mexico By The Atchafalaya River, A Major Distributary Of The Mississippi River, April Elizabeth Bryantmason Jan 2012

Nitrogen And Carbon Export To The Gulf Of Mexico By The Atchafalaya River, A Major Distributary Of The Mississippi River, April Elizabeth Bryantmason

LSU Doctoral Dissertations

Summer hypoxia in the Northern Gulf of Mexico has been attributed to large nutrient inputs, especially nitrate-nitrogen, from the Mississippi-Atchafalaya River system. The 2008 Gulf Hypoxia Action Plan calls for river corridor wetland restoration to reduce nitrate loads, but it is largely unknown how effective riverine wetland systems in the lower Mississippi River (MR) are for nitrate removal. This dissertation research examined nitrate and carbon export from the Atchafalaya River (AR) to: (1) determine nitrate processing by a river swamp basin under varied seasons, (2) investigate nitrate retention and processing in the AR during a major flood event, and (3) …

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Function And Diversity Of The Ship, Trinity, And Tiger Shoal Complex, With Emphasis On Macrofauna And Spawning Blue Crabs (Callinectes Sapidus), Carey George Gelpi Jr. Jan 2012

Function And Diversity Of The Ship, Trinity, And Tiger Shoal Complex, With Emphasis On Macrofauna And Spawning Blue Crabs (Callinectes Sapidus), Carey George Gelpi Jr.

LSU Doctoral Dissertations

The ecological and economic value of sandy shoals off the Louisiana coast is not well understood. During three years of comprehensive benthic sampling and environmental measurements I studied the Ship, Trinity, Tiger Shoal Complex (STTSC), which comprises changing and discrete benthic habitats including high relief sandy shoals, and muddier, mostly deeper off-shoal areas, prone to hypoxia. Benthic macrofaunal assemblages of shoals included endemic species, and shoal communities were significantly different from each other and the muddier offshoal habitat, contributing to northern Gulf of Mexico (GoM) regional biodiversity. Sand percentage was the most influential environmental parameter shaping macrofaunal community composition across …

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Cluster Based Jamming And Countermeasures For Wireless Sensor Network Mac Protocols, David Trammell Jan 2012

Cluster Based Jamming And Countermeasures For Wireless Sensor Network Mac Protocols, David Trammell

LSU Doctoral Dissertations

A wireless sensor network (WSN) is a collection of wireless nodes, usually with limited computing resources and available energy. The medium access control layer (MAC layer) directly guides the radio hardware and manages access to the radio spectrum in controlled way. A top priority for a WSN MAC protocol is to conserve energy, however tailoring the algorithm for this purpose can create or expose a number of security vulnerabilities. In particular, a regular duty cycle makes a node vulnerable to periodic jamming attacks. This vulnerability limits the use of use of a WSN in applications requiring high levels of security. …

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