Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

2008

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 12631 - 12660 of 15505

Full-Text Articles in Entire DC Network

Trophic Control Of Saltmarsh Invertebrates, David Samuel Johnson Jan 2008

Trophic Control Of Saltmarsh Invertebrates, David Samuel Johnson

LSU Doctoral Dissertations

Top-down (consumer) versus bottom-up (resource) control of food webs has long interested ecologists. Here, I take advantage of a full-factorial design of ecosystem-wide manipulations of nutrient additions (loading rates 10x above background) and the significant reduction (~60%) of a key predator, the killifish Fundulus heteroclitus, in the tidal creeks of the Plum Island Estuary, Massachusetts. Prior to manipulations, annelids numerically constituted 97% of the infaunal community and the largest scale (creeks) accounted for little spatial variability in annelid populations and diversities. Tidal creeks were similar based on diversity indices, abundance, and community patterns, suggesting the tidal creeks are appropriate replicates/experimental …

Go to article

Avian Diversification In The Afrotropics, Ben D. Marks Jan 2008

Avian Diversification In The Afrotropics, Ben D. Marks

LSU Doctoral Dissertations

Widespread bird species endemic to the lowlands of the Guineo-Congolian rainforest of Africa have traditionally been thought to lack substantial intraspecific structure. This view owes largely to their widespread distributions coupled with the absence of discrete geographic variation in plumage. In the following chapters I examine the phylogeographic patterns of three such species using a combination of molecular and morphometric data. The three species investigated are the Green Hylia (Hylia prasina), the Red-tailed Bristlebill (Bleda syndactylus), and the Yellow-whiskered Greenbul (Andropadus latirostris). Using the phylogeographic patterns from these data, I assess 1) models of rainforest species diversification, 2) current taxonomy, …

Go to article

Digital Storytelling As A Literacy-Based Intervention For A Sixth Grade Student With Autism Spectrum Disorder: An Exploratory Case Study, Brent A. Daigle Jan 2008

Digital Storytelling As A Literacy-Based Intervention For A Sixth Grade Student With Autism Spectrum Disorder: An Exploratory Case Study, Brent A. Daigle

LSU Doctoral Dissertations

This study investigates the use of Digital Storytelling as an intervention to improve the academic performance and social interactions of a sixth grade student with High-Functioning Autism. Qualitative methodology, using an inductive approach informed by grounded theory, was employed throughout this exploratory case study. Three separate data sources, consisting of document analysis, interviews, and participant observation, contributed to the findings of this study. Triangulation of inquiry methods enhanced the validity and rigor of this investigation. The findings from this inquiry indicate that Digital Storytelling was beneficial to the participant in this exploratory case study. Engaged student processes and critical analysis …

Go to article

The Diet Of Saltmarsh Consumers, Kari Ann Galvan Jan 2008

The Diet Of Saltmarsh Consumers, Kari Ann Galvan

LSU Doctoral Dissertations

Salt marshes are areas of high primary production that in turn support high secondary production. Macrophytes, phytoplankton and a variety of benthic algae all contribute to the high primary productivity. Each has the potential to contribute to the saltmarsh food web making it difficult to determine organic matter resources important to secondary production in salt marshes. Furthermore, our understanding of saltmarsh food webs is complicated by anthropogenic effects such as nutrient inputs and exploitation of key predators. I utilized a combination of natural abundance stable isotopes, isotope tracer additions, gut content analysis and manipulative experiments to determine the diets of …

Go to article

Bioanalytical Methods For Studies Of Homocysteine And Novel Cardiovascular Disease Indicators, Arther T. Gates Jan 2008

Bioanalytical Methods For Studies Of Homocysteine And Novel Cardiovascular Disease Indicators, Arther T. Gates

LSU Doctoral Dissertations

This dissertation explores the development of analytical methods for studies of CVD biomarkers and related biomolecular indicators. Initially, spectroscopic studies were conducted to investigate the chemical reactivity of homocysteine (Hcy), an independent CVD risk factor and serological biomarker. Consequently, we proposed an alternate theory for in vivo Hcy clearance based on spontaneous pyridoxal tetrahydrothiazine (PT) formation from Hcy and pyridoxal. The validity of PT-assisted Hcy clearance was further evaluated by use of capillary electrophoretic methods, which allowed rapid monitoring of protein oligomerization in PT-protein reaction mixtures. The results of these studies suggest that PT formation is a plausible mechanism for …

Go to article

Climate Change And The Environmental Impact Review Process, Michael B. Gerrard Jan 2008

Climate Change And The Environmental Impact Review Process, Michael B. Gerrard

Faculty Scholarship

In the explosion of modern environmental law that occurred in the 1970s, the first major statute was the National Environmental Policy Act (NEPA), 42 U.S.C. §§ 4321-4347, signed into law by President Richard M. Nixon on January 1, 1970. It spawned "little NEPAs" in about twenty-five states and eighty countries. Council on Environmental Quality, The National Environmental Quality Act: A Study of Its Effectiveness After Twenty-Five Years (1997). All of these laws were designed to require governments to consider environmental issues in their decisions. The chief mechanism of NEPA and its state equivalents is the preparation of environmental impact statements …

Go to article

Seeing And Believing: Mandatory Ultrasound And The Path To A Protected Choice, Carol Sanger Jan 2008

Seeing And Believing: Mandatory Ultrasound And The Path To A Protected Choice, Carol Sanger

Faculty Scholarship

Several state legislatures now require that before a woman may consent to an abortion, she must first undergo an ultrasound and be offered the image of her fetus. The justification is that without an ultrasound, her consent will not be fully informed. Such legislation, the latest move in abortion regulation, supposes that a woman who sees the image will be less likely to abort. This Article explores how visual politics has combined with visual technology, and how law has seized upon both in a campaign to encourage women to choose against abortion. While rarely analyzed, the significance of seeing, or …

Go to article

Fundamentals Of Biology, Steelman Library, Todd Schraw Dr. Jan 2008

Fundamentals Of Biology, Steelman Library, Todd Schraw Dr.

Syllabus Repository

No abstract provided.

Go to article

Release And Removal Of Microcystins From Microcystis During Disinfection Treatments, Jie Ding Jan 2008

Release And Removal Of Microcystins From Microcystis During Disinfection Treatments, Jie Ding

Masters Theses

"The presence of algal toxins, or cyanotoxins, in surface water has been increasingly reported. These highly hazardous toxins are potential threat to both human health and animals by contaminating drinking water sources over the world. In this research project, inactivation of Microcystis aeruginosa cells and release and removal of intracellular microcystins during several oxidative and physical treatments was studied. The results of this study show that chlorine dioxide, sonication, low salinity and quick blending with tissuemiser caused immediate release of microcystin-LR to water after treatment. No significant increase of toxin level was observed after treatment with free chlorine, ozone, permanganate, …

Go to article

Women In Science: Stories From The Margins, Laura Mathis Mulvanity Jan 2008

Women In Science: Stories From The Margins, Laura Mathis Mulvanity

College of Graduate Studies: Theses & Dissertations

Women are significantly underrepresented in the hard sciences and engineering. While the number of women seeking degrees in these fields has increased in the last forty years, a substantial gap still exists between the sexes. The purpose of this dissertation is to examine one area of influence on career choice -- the curriculum. Women scientists are underrepresented in the school curriculum. This dissertation examines the discourse of curriculum and the role it has in the gendering of the field of science. The nature of the development of a curriculum lends itself to the practice of exclusion. The construction of curriculum …

Go to article

Species Boundaries, Biogeography, And Intra-Archipelago Genetic Variation Within The Emoia Samoensis Species Group In The Vanuatu Archipelago And Oceania, Alison Madeline Hamilton Jan 2008

Species Boundaries, Biogeography, And Intra-Archipelago Genetic Variation Within The Emoia Samoensis Species Group In The Vanuatu Archipelago And Oceania, Alison Madeline Hamilton

LSU Doctoral Dissertations

Speciation, geographic variation, and genetic differentiation are fundamental processes that generate diversity, and understanding these processes are major goals of evolutionary biology. Evolutionary phenomena may be more observable on islands as compared to continental landmasses as a result of small population sizes, unoccupied niches, and the relative simplicity of island systems and their populations: physical isolation, shorter (and often well documented) geologic time scale, reduced faunal diversity, and lack of outside faunal influence. Yet, despite their incredible diversity, Pacific island faunas have received little research attention relative to other tropical regions. Using molecular data from several species of scincid lizards …

Go to article

Neonatal Respiratory Virus Infection Shapes Pulmonary Function In Adult Mice, Dahui You Jan 2008

Neonatal Respiratory Virus Infection Shapes Pulmonary Function In Adult Mice, Dahui You

LSU Doctoral Dissertations

Respiratory syncytial virus (RSV) and influenza are the two most common causes of acute lower respiratory tract infections in infants. Epidemiological data suggest that both severe RSV and influenza infections during infancy are associated with long-term pulmonary function abnormalities. Despite of the severe burdens of RSV and influenza infections in infants, no efficacious vaccines are available for RSV and the current vaccine strategy for influenza is inconvenient due to the fact that vaccines are made annually based on the prediction of circulating strains in the next season. New strategies in vaccine development have been slow to arrive partly due to …

Go to article

A Tour-De-Force In Polymer Crosslinked Aerogels, Sudhir Mulik Jan 2008

A Tour-De-Force In Polymer Crosslinked Aerogels, Sudhir Mulik

Doctoral Dissertations

"In the quest of building mechanically strong materials with low density and high porosity, polymer crosslinked aerogels stand as the most promising nano-engineered examples. Covalent attachment of polymers and bridging of skeletal nanoparticles of typical aerogels is demonstrated by using surface initiated polymerization (SIP) with a bidentate free-radical initiator structurally related to azobisisobutyronitrile (AIBN) and confined on mesoporous silica surfaces. Different monomers were introduced in the mesopores and upon heating at 70⁰C, all mesoporous surfaces throughout the entire skeletal framework were coated conformally with a 10-12 nm thick polymer layer indistinguishable spectroscopically from the respective commercial bulk materials. The new …

Go to article

Removal Of Heavy Metals From Electroplating Wastewater Using Rice Husk And Coconut Coir, Frency Mathew Jan 2008

Removal Of Heavy Metals From Electroplating Wastewater Using Rice Husk And Coconut Coir, Frency Mathew

Masters Theses

"Heavy metal toxicity due to industrial wastewater has been a threat to the environment for the past many decades, especially in the developing countries such as India, China and Thailand where cost effectiveness of the removal process is a major factor. In this research, the effectiveness of two natural adsorbents, rice husk (RH) and coconut coir (CC), which are cheaply available in these countries for the removal of heavy metals from electroplating wastewaters were studied"--Abstract, page iii.

Go to article

A Laboratory Study Of Struvite Precipitation For Phosphorus Removal From Concentrated Animal Feeding Operation Wastewater, Sushmita Dhakal Jan 2008

A Laboratory Study Of Struvite Precipitation For Phosphorus Removal From Concentrated Animal Feeding Operation Wastewater, Sushmita Dhakal

Masters Theses

"Struvite precipitation occurs spontaneously in many wastewater treatment facilities as a nuisance. However, struvite precipitation is now being studied as a method to concurrently treat high phosphorus wastewaters and generate a valuable product. Many factors influence the precipitation of struvite such as component -ion molar ratios, pH, aeration, solubility, solids and mixing energy. In the present work, struvite precipitation in the actual swine wastewater was studied by strategically controlling aeration, pH, and mixing"--Abstract, page iv.

Go to article

Co-Optimization: A Generalization Of Coevolution, Travis Service Jan 2008

Co-Optimization: A Generalization Of Coevolution, Travis Service

Masters Theses

"Many problems encountered in computer science are best stated in terms of interactions amongst individuals. For example, many problems are most naturally phrased in terms of finding a candidate solution which performs best against a set of test cases. In such situations, methods are needed to find candidate solutions which are expected to perform best over all test cases. Coevolution holds the promise of addressing such problems by employing principles from biological evolution, where populations of candidate solutions and test cases are evolved over time to produce higher quality solutions...This thesis presents a generalization of coevolution to co-optimization, where optimization …

Go to article

A Time Series Classifier, Christopher Mark Gore Jan 2008

A Time Series Classifier, Christopher Mark Gore

Masters Theses

"A time series is a sequence of data measured at successive time intervals. Time series analysis refers to all of the methods employed to understand such data, either with the purpose of explaining the underlying system producing the data or to try to predict future data points in the time series...An evolutionary algorithm is a non-deterministic method of searching a solution space, and modeled after biological evolutionary processes. A learning classifier system (LCS) is a form of evolutionary algorithm that operates on a population of mapping rules. We introduce the time series classifier TSC, a new type of LCS that …

Go to article

Role Of Microtubules In Budding Yeast Cytokinesis, Su Young Park Jan 2008

Role Of Microtubules In Budding Yeast Cytokinesis, Su Young Park

Masters Theses

"Cytokinesis is an important step to finish cell cycle events and separate into two daughter cells. This event is driven by actomyosin ring contraction. In budding yeast, the mitotic exit network (MEN) controls completion of ana/telophase by signaling events. Bub2 is a mitotic exit network regulator and binds to Tem1p which is an important component in MEN. Mad2 is a component of a separate spindle checkpoint. Mad2 dependent pathway prevents the metaphase to anaphase transition under spindle damage. Because yeast cells have cell walls, septum formation follows actin ring contraction. Here it was investigated how microtubule defects affect cytokinesis in …

Go to article

Transcriptome Analysis Of Alzheimer's Disease Identifies Links To Cardiovascular Disease, Monika Ray, Jianhua Ruan, Weixiong Zhang Jan 2008

Transcriptome Analysis Of Alzheimer's Disease Identifies Links To Cardiovascular Disease, Monika Ray, Jianhua Ruan, Weixiong Zhang

All Computer Science and Engineering Research

No abstract provided.

Go to article

How To Measure And Report Growing Conditions For Experiments In Controlled Environments., M. P. Fuller, J. Franklin, L. D. Incoll Jan 2008

How To Measure And Report Growing Conditions For Experiments In Controlled Environments., M. P. Fuller, J. Franklin, L. D. Incoll

School of Biological and Marine Sciences

No abstract provided.

Go to article

Modeling Motor Pattern Generation In The Development Of Infant Speech Production, Is Howard, P Messum Jan 2008

Modeling Motor Pattern Generation In The Development Of Infant Speech Production, Is Howard, P Messum

School of Engineering, Computing and Mathematics

We previously proposed a non-imitative account of learning to pronounce, implemented computationally using discovery and mirrored interaction with a caregiver. Our model used an infant vocal tract synthesizer and its articulators were driven by a simple motor system. During an initial phase, motor patterns develop that represent potentially useful speech sounds. To increase the realism of this model we now include some of the constraints imposed by speech breathing. We also implement a more sophisticated motor system. Firstly, this can independently control articulator movement over different timescales, which is necessary to effectively control respiration as well as prosody. Secondly, we …

Go to article

How People Should Respond When Encountering A Large Carnivore: Opinions Of Wildlife Professionals, Dylan E. Brown, Michael R. Conover Jan 2008

How People Should Respond When Encountering A Large Carnivore: Opinions Of Wildlife Professionals, Dylan E. Brown, Michael R. Conover

Human–Wildlife Interactions

We conducted telephone surveys of wildlife professionals who work with large carnivores to ask their opinions about how people should respond to avoid being injured when confronted by a black bear (Ursus americana), grizzly bear (Ursus arctos), mountain lion (Puma concolor), or gray wolf (Canis lupus). The respondents agreed that the most appropriate response was to try to increase the distance between a person and the carnivore. In the event of an attack by a black bear, mountain lion, or wolf, most respondents said to fight back. Opinion was divided over the …

Go to article

Carnivores, Urban Landscapes, And Longitudinal Studies: A Case History Of Black Bears, Jon P. Beckmann, Cael W. Lackey Jan 2008

Carnivores, Urban Landscapes, And Longitudinal Studies: A Case History Of Black Bears, Jon P. Beckmann, Cael W. Lackey

Human–Wildlife Interactions

As urban landscapes expand across the globe, it becomes imperative to understand how these landscapes affect large carnivore populations. We examined the effects of human-altered landscapes on age-specific fecundity and life history parameters for female black bears (Ursus americanus) in urban and wildland regions in the northern Sierra Nevada Mountains of Nevada, including the Lake Tahoe Basin. We followed 12 marked female bears in an urban environment and 10 females in wildland habitats from 1997–2006. Our results show that female bears in urban areas have higher age-specific fecundity rates than did wildland female bears. Despite this difference, female …

Go to article

Evaluation Of An Oral Vaccination Program To Control Raccoon Rabies In A Suburbanized Landscape, Jason R. Boulanger, Laura L. Bigler, Paul D. Curtis, Donald H. Lein, Arthur J. Lembo Jr. Jan 2008

Evaluation Of An Oral Vaccination Program To Control Raccoon Rabies In A Suburbanized Landscape, Jason R. Boulanger, Laura L. Bigler, Paul D. Curtis, Donald H. Lein, Arthur J. Lembo Jr.

Human–Wildlife Interactions

We evaluated the efficacy of an oral rabies vaccination (ORV) program conducted in Erie County, New York, from July through September, 2002–2005. Ingress of the raccoon (Procyon lotor) rabies variant first occurred along the southern border of Erie County, New York, during 1992 and began to spread northward at a velocity of 31 km/year. Fixed-wing aircraft dropped ORV baits in rural landscapes; helicopters, hand baiting, and bait stations distributed baits in suburban landscapes (&#;x bait densities ranged 59–118 baits/km2). Our study objectives were to quantify rabies case densities, evaluate efficacy of intervention efforts, and determine biological, …

Go to article

Mammalian Hazards At Small Airports In Indiana: Impact Of Perimeter Fencing, Travis L. Devault, Jacob E. Kubel, David J. Glista, Olin E. Rhodes Jr. Jan 2008

Mammalian Hazards At Small Airports In Indiana: Impact Of Perimeter Fencing, Travis L. Devault, Jacob E. Kubel, David J. Glista, Olin E. Rhodes Jr.

Human–Wildlife Interactions

Fences are used at many airports and small airfields to exclude wildlife from entering critical areas. However, not all fences exclude hazardous mammals reliably, and effective fences can be too expensive for small airports to purchase and maintain. In this study, we evaluated fencing at 10 small airports in Indiana and documented the presence and relative abundance of wildlife within airport boundaries using remote cameras and spotlight surveys. Only 4 airports were completely fenced, and four were Odocoileus virginianus) or coyotes (Canis latrans) at nine of the airports with remote cameras and during spotlight surveys. There were fewer …

Go to article

Resolving Conflicts Between Humans And The Threatened Louisiana Black Bear, Walter Cotton Jan 2008

Resolving Conflicts Between Humans And The Threatened Louisiana Black Bear, Walter Cotton

Human–Wildlife Interactions

The Louisiana black bear (Ursus americanus luteolus) is one of 16 subspecies of American black bear. At the time of English settlement, this subspecies was abundant throughout Louisiana, the southern two-thirds of Mississippi, eastern Texas, and extreme southern Arkansas. By the 1950s, Louisiana black bears had been extirpated from most of their original range due to habitat destruction and fragmentation and over-harvest by hunters (Leigh and Chamberlain 2008). It is believed that only about 100 black bears remained; existing in isolated, extremely rural areas of eastern Louisiana. Bears became so scarce during the 1960s that the Louisiana Department …

Go to article

Modeling Wildlife Damage To Crops In Northern Indiana, Mónica I. Retamosa, Lee A. Humberg, James C. Beasley, Olin E. Rhodes Jr. Jan 2008

Modeling Wildlife Damage To Crops In Northern Indiana, Mónica I. Retamosa, Lee A. Humberg, James C. Beasley, Olin E. Rhodes Jr.

Human–Wildlife Interactions

Comprehensive information on crop damage by wildlife species is critical if effective strategies for controlling wildlife damage are to be formulated. Discriminating how landscape composition and configuration attributes influence crop damage is important for implementing landscape management techniques to resolve human–wildlife conflicts. We analyzed crop damage data from 100 corn fields and 60 soybean fields located in the Upper Wabash River Basin of northern Indiana during 2003 and 2004. We used negative binomial regression to model the rate of damage to corn and soybean crops in response to local and landscape variables. Rate of crop damage was best predicted by …

Go to article

Evaluation Of Physical Barriers To Prevent Prairie Dog Colony Expansion, Gary Witmer, James Gionfriddo, Michael Pipas Jan 2008

Evaluation Of Physical Barriers To Prevent Prairie Dog Colony Expansion, Gary Witmer, James Gionfriddo, Michael Pipas

Human–Wildlife Interactions

Expansion of black-tailed prairie dog (Cynomys ludovicianus) colonies on public and private lands can result in damage to property. Physical barriers to prairie dogs can be used to minimize human–wildlife conflicts. We evaluated 17 existing barriers in the Fort Collins and Boulder, Colorado, areas. Most barriers were made of a single row of vinyl material; these barriers sustained high levels of damage, primarily from wind, and were frequently breached by prairie dogs digging underneath them. Barriers that included a vegetation and a vinyl barrier or a double-vinyl barrier were wind damaged and breached less frequently than the single-vinyl …

Go to article

Trans Fatty Acids Provide Evidence Of Anthropogenic Feeding By Black Bears, Gregory W. Thiemann, Randal S. Stahl, Sharon Baruch-Mordo, Stewart W. Breck Jan 2008

Trans Fatty Acids Provide Evidence Of Anthropogenic Feeding By Black Bears, Gregory W. Thiemann, Randal S. Stahl, Sharon Baruch-Mordo, Stewart W. Breck

Human–Wildlife Interactions

Bears (Ursus spp.) that become conditioned to anthropogenic food sources pose a risk to human safety and generally need to be relocated, rehabilitated, or destroyed. Identifying food-conditioned bears may be difficult if the animal is not captured or killed while immediately engaged in the nuisance behavior. Fatty acid signature analysis has been used to examine the dietary habits of bears and other carnivores and is based on the predictable incorporation of ingested fatty acids into the consumer’s fat stores. Unusual fatty acids that are available in only a few food types may be particularly useful dietary markers. In this …

Go to article

Relationship Between Raccoon Abundance And Crop Damage, James C. Beasley, Olin E. Rhodes Jr. Jan 2008

Relationship Between Raccoon Abundance And Crop Damage, James C. Beasley, Olin E. Rhodes Jr.

Human–Wildlife Interactions

Wildlife damage to crops is a widespread concern among agricultural producers and wildlife professionals. In the United States, raccoon (Procyon lotor) damage to field corn (Zea maize) has become a serious concern, as raccoon depredation to corn has increased significantly in recent years. However, little information is available to suggest the underlying factors responsible for recent increases in raccoon depredation on agricultural crops because there is a limited understanding of the ecological factors influencing wildlife damage to crops at local scales. During 2004, we initiated a study to elucidate the ecological factors influencing depredation to field …

Go to article

First Prev Next Last