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Effect Of Age, Body Condition, Pregnancy And Lactation On Circulating Leptin Concentrations In Beef Cattle, Glen Talmage Gentry, Jr. Jan 2007

Effect Of Age, Body Condition, Pregnancy And Lactation On Circulating Leptin Concentrations In Beef Cattle, Glen Talmage Gentry, Jr.

LSU Doctoral Dissertations

A series of experiments were conducted to evaluate the potential role of leptin in bovine reproduction. In Experiment 1, mean circulating leptin concentrations of postpartum cows were not affected by exogenous dexamethasone treatments. In Experiment 2, mean leptin concentrations were not correlated with female age or body weight but were positively correlated with body condition scores of beef cattle. Leptin concentrations were higher in 1 year old heifers (8.9 ng/ml) compared with 2 year old cows (6.0 ng/ml), but heifer leptin concentrations were not different than 4 to 6 year old cows (8.0 ng/ml) and cows ≥7 years of age …

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Chemical Ecology, Fungal Interactions And Forest Stand Correlations Of The Exotic Asian Ambrosia Beetle, Xylosandrus Crassiusculus (Motschulsky) (Curculionidae), Eric Paul Ott Jan 2007

Chemical Ecology, Fungal Interactions And Forest Stand Correlations Of The Exotic Asian Ambrosia Beetle, Xylosandrus Crassiusculus (Motschulsky) (Curculionidae), Eric Paul Ott

LSU Master's Theses

Increasing evidence of non-indigenous ambrosia beetles aggressively attacking hosts in their new environment in the United States has led to concern over the potential for damage to urban trees, nurseries, orchards, and forests. A novel technique of flooding host trees was devised to stimulate ambrosia beetle attacks, with ambrosia beetle attraction peaking four days following flooding. In-situ sampling identified significant differences in the composition, quantity and point of release (leaf or bole) of volatiles emitted by the flooded and non-flooded trees. Coupled gas chromatography electroantennographic detection revealed olfactory sensitivity by the ambrosia beetle Xylosandrus crassiusculus (Motschulsky) to 29 of these …

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The Particulate Nature Of Polyatomic Ions: An Exploratory Study Using Molecular Drawing Software, Leodore Mathew, Jr. Amiot Jan 2007

The Particulate Nature Of Polyatomic Ions: An Exploratory Study Using Molecular Drawing Software, Leodore Mathew, Jr. Amiot

LSU Doctoral Dissertations

The purpose of this study was to determine if the use of molecular drawing software would improve student understanding of polyatomic ions. Using software designed for producing drawings of molecules, students developed drawings of polyatomic ions during a regular activity of the state mandated core curriculum on ions. The sample consisted of students enrolled in chemistry at a rural south Louisiana high school-both Honors and Regular. Pretest and posttest scores were analyzed with a number of covariants. The statistical analysis of test scores indicated that there was no significant difference in the improved test scores between the treatment and control …

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The Role Of Olympia In Charles Mee's Big Love: A Production Thesis In Acting, Elizabeth Nicole Travis Jan 2007

The Role Of Olympia In Charles Mee's Big Love: A Production Thesis In Acting, Elizabeth Nicole Travis

LSU Master's Theses

The role of Olympia in Charles Mee’s Big Love was selected as a thesis project in the fall semester of 2006. This thesis is a written record of the actor’s work on the character throughout the rehearsal process and performance in the form of an Actor’s Score. It also includes an Introduction, a Chapter on the Rehearsal Process, Character Analysis, News Article, Production Photo and a Conclusion.

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Biogeomorphic Evaluation Of Caminada-Moreau Maritime Beach Ridges With Respect To Future Restoration Initiatives, Hannon Didier Jan 2007

Biogeomorphic Evaluation Of Caminada-Moreau Maritime Beach Ridges With Respect To Future Restoration Initiatives, Hannon Didier

LSU Master's Theses

Restoration efforts within the coastal zone of southern Louisiana have assumed greater importance in the wake of recent storms and ever increasing sea level rise. A poorly studied geomorphic structure known as the Caminada-Moreau maritime beach ridge complex exists along the southeastern Louisiana coastline between Grand Isle and the Port of Fourchon. Active subsidence in the area has reduced the overall elevation of these structures, decreasing the live cover of its most noticeable feature, stands of Quercus virginiana (live oak), along the ridge spines. Elevation data was gathered along and across four randomly selected ridges in the study area with …

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Chagas In Culture And Place: A Mixed Methods Approach To A New Medical Geography Of Chagas Disease In Los Tuxtlas, Mexico, Frances Heyward Currin Mujica Jan 2007

Chagas In Culture And Place: A Mixed Methods Approach To A New Medical Geography Of Chagas Disease In Los Tuxtlas, Mexico, Frances Heyward Currin Mujica

LSU Doctoral Dissertations

This project is concerned with a new medical geography approach to investigating Chagas disease in Los Tuxtlas, Mexico which focuses on the intersection of disease risk and place. More specifically this work will describe the domestic cycle of Chagas disease and the cultural factors that perpetuate its transmission in six communities in the Los Tuxtlas region, Municipio San Andres, Veracruz State, Mexico. Using several collection techniques, such as interviews and house type surveys, as well as identifying and collecting the vector Triatoma dimidiata (including testing them for the parasite Trypanosoma cruzi), this dissertation describes the characteristics of the Chagas landscape …

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Development Of Micropump For Microfluidic Applications, Dong Eun Lee Jan 2007

Development Of Micropump For Microfluidic Applications, Dong Eun Lee

LSU Doctoral Dissertations

This dissertation covers the research work on two types of micropumps, one is based on magnetohydrodynamic (MHD) principle that utilizes Lorentz force for actuation, and the other is based on electrochemical actuation. The AC-type MHD micropump was designed and analyzed as a solution to the bubble formation problem encountered in DC-type MHD micropump. A UV-LIGA process using thick layer of SU-8 negative photoresist was successfully developed to microfabricate the AC MHD micropump. Preliminary studies and tests of the AC MHD micropumps demonstrate that bubble formation was significantly reduced to permit the proper function of the micropump. A continuous flow was …

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Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang Jan 2007

Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang

LSU Doctoral Dissertations

Useful mechanistic studies to date concerning sugar detection by arylboronic acid chemosensors have mainly involved the elucidation of equilibrium constants and the role of boron-nitrogen interactions in signal transduction. However, several discreet sugarboronate complexes exist in solution. This is due to the complex equilibria between isomeric species of even the simplest monosaccharides. Relatively few reports have been devoted to a systematic study of the structures of each of the corresponding individual sugar-boronate complexes. We have investigated some of the precise regio- and stereochemical features of the various equilibrating sugar isomers that induce selective signal transduction. As a result of this …

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Spatial And Temporal Structure Of Typhoid Fever In Washington, D.C., 1895-1909: A Geographic Information Systems Exploration Of Urban Health Concerns, Sarah Elizabeth Hinman Jan 2007

Spatial And Temporal Structure Of Typhoid Fever In Washington, D.C., 1895-1909: A Geographic Information Systems Exploration Of Urban Health Concerns, Sarah Elizabeth Hinman

LSU Doctoral Dissertations

The period between 1880 and 1920 was one of the most dynamic in the history of medicine. Morbidity and mortality rates for infectious diseases dropped quickly. Concurrently, miasmatic theory gave way to germ theory. Many of these dynamic changes occurred in the urban centers of North America, which were also entering into a period of dramatic growth and change. Following the 1905 completion of infrastructure improvements intended to improve public health in Washington, D.C., typhoid fever rates unexpectedly increased. Previously, for mitigation purposes, Dr. George Kober investigated a typhoid epidemic in 1895, and as a result of the 1906 increase …

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The Role Of The Merchant In Bertolt Brecht's The Exception And The Rule: A Production Thesis In Acting, Mark Jaynes Jan 2007

The Role Of The Merchant In Bertolt Brecht's The Exception And The Rule: A Production Thesis In Acting, Mark Jaynes

LSU Master's Theses

The role of the Merchant in Bertolt Brecht’s The Exception and the Rule was selected as the topic of this production thesis in acting to be submitted unto the Graduate School of Louisiana State University in partial fulfillment of the requirements for graduation with the Master of Fine Arts degree in Theatre. The thesis includes an introduction, a chapter on preparation for the role, a chapter on implementation of the role, a physical score and a conclusion. It details the author’s approach to the role of the Merchant in performance, as well as to the performance theories of Bertolt Brecht …

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Competencies For Rural Nursing Practice, Florence Elaine Hurme Jan 2007

Competencies For Rural Nursing Practice, Florence Elaine Hurme

LSU Doctoral Dissertations

This study sought to identify nursing competencies most associated with good nursing practice in Critical Access Hospitals. The Delphi panel for this study consisted of seven rural health nurse experts who were currently employed as a Director of Nursing in a Critical Access Hospital. A survey instrument was developed for each of the three Delphi rounds. The Round One instrument consisted of two open-ended focus questions. The four classification headings used for the identified competencies included Clinical/Technical Skills, Critical Thinking Skills, Communication/Interpersonal Skills, and Management/Organizational Skills. The Round Two survey instrument was a compilation of the competencies received from the …

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Isolation And Characterization Of Two Closely Related Beta-Carbonic Anhydrases Of Chlamydomonas Reinhardtii, Ruby Agno Ynalvez Jan 2007

Isolation And Characterization Of Two Closely Related Beta-Carbonic Anhydrases Of Chlamydomonas Reinhardtii, Ruby Agno Ynalvez

LSU Doctoral Dissertations

Aquatic photosynthetic organisms such as the green alga, C. reinhardtii respond to low carbon dioxide conditions by inducing a carbon dioxide concentrating mechanism (CCM). Important components of the CCM are carbonic anhydrases (CAs), zinc metalloenzymes that catalyze the interconversion of carbon dioxide and bicarbonate. C. reinhardtii now has nine carbonic anhydrases, three alpha-CAs and six beta-CAs. This dissertation describes the identification and characterization of two closely related beta-CAs, CAH7 and CAH8. These CAs are 63% identical. CAH7 and CAH8 encode proteins of 399 and 333 amino acids, respectively. Both of these CAs are constitutively expressed at the transcript and protein …

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An Exploration Of The Impact Of Picture Book Illustrations On The Comprehension Skills And Vocabulary Development Of Emergent Readers, Judy Lavender Nicholas Jan 2007

An Exploration Of The Impact Of Picture Book Illustrations On The Comprehension Skills And Vocabulary Development Of Emergent Readers, Judy Lavender Nicholas

LSU Doctoral Dissertations

The formal instruction process of teaching reading to emergent and beginning readers needs to incorporate a much more multimodal approach. People today, not only in America but in many other countries as well, are more graphically oriented than any other generation has ever been. Children in our society expect to experience pictures and images in almost everything they encounter. This graphic orientation needs to be taken advantage of and incorporated into the educational process in ways that can be beneficial to the learning environments of children in our schools. Reading programs need to forego one-dimensional teaching methods and learn how …

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Analysis Of Miocene Stratigraphy And Sedimentology In The Ross Sea, Antarctica: A First Order Test Of Proxy Based Climate Interpretations, Samuel Gray Jan 2007

Analysis Of Miocene Stratigraphy And Sedimentology In The Ross Sea, Antarctica: A First Order Test Of Proxy Based Climate Interpretations, Samuel Gray

LSU Master's Theses

During the Cenozoic, the climate progressed from global warmth into an icehouse world. This study investigates the links between the development of the climate and cryosphere using sediment flux and stratal geometries. The current polar conditions are characterized by dry basal conditions, which due to minimal melt water produce significantly less sediment than their temperate counterparts. Therefore, the transition from temperate to polar conditions should have resulted in marked decrease in sediment flux and change in stratal geometries in adjacent marine margins. Regional seismic stratigraphic evidence clearly suggests that ice has been intermittently grounded on the Ross Sea outer continental …

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Error Training: An Examination Of Metacognition, Emotion Control, Intrinsic Motivation, And Knowledge As Mediators Of Performance Effects, Natalie T. Bourgeois Jan 2007

Error Training: An Examination Of Metacognition, Emotion Control, Intrinsic Motivation, And Knowledge As Mediators Of Performance Effects, Natalie T. Bourgeois

LSU Doctoral Dissertations

Error Management Training (EMT) is a method of training that encourages trainees to make errors during training and to view those errors as beneficial for learning. Previous research has shown support for the benefits of EMT on metacognition, emotion control, intrinsic motivation and transfer performance compared to traditional error avoidant training. Also, previous research has found support for the mediating effects of metacognition and emotion control on the training type (i.e., EMT vs. error avoidant) and transfer performance relationship. However, previous research has not determined whether the increased metacognition, emotion control, and intrinsic motivation of EMT individuals has its effects …

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Lanthanide Complexes As Fluorescent Indicators For Neutral Sugars And Cancer Biomarkers, Onur Alpturk Jan 2007

Lanthanide Complexes As Fluorescent Indicators For Neutral Sugars And Cancer Biomarkers, Onur Alpturk

LSU Doctoral Dissertations

Simple water soluble lanthanum and europium complexes are effective at detecting neutral sugars as well as glyco- and phospholipids. In solutions at physiologically relevant pH the fluorescent lanthanum complex binds neutral sugars with apparent binding constants comparable to those of arylboronic acids. Interference from commonly occurring anions is minimal. The europium complex detects sialic acid-containing gangliosides at pH 7.0 over an asialoganglioside. This selectivity is attributed, in large part, to the cooperative complexation of the oligosaccharide and sialic acid residues to the metal center, based on analogous prior studies. In MeOH, lysophosphatidic acid (LPA), a biomarker for several pathological conditions …

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Investigation On The Antioxidant Capabilities Of Spice Extracts In Inhibition Of Long Chain Polyunsaturated Fatty Acids Oxidation And Cholesterol, Sandeep D. Bhale Jan 2007

Investigation On The Antioxidant Capabilities Of Spice Extracts In Inhibition Of Long Chain Polyunsaturated Fatty Acids Oxidation And Cholesterol, Sandeep D. Bhale

LSU Doctoral Dissertations

Antioxidant capabilities of the spice extract of ginger, oregano, rosemary and turmeric were evaluated by monitoring inhibition of DHA and EPA in a menhaden fish oil model and cholesterol oxidation model system. The spice extracts were mixed with the fish oil at 1, 2.5 and 5 % (w/w) and 1, 2.5 and 5mg (dw) were used in cholesterol study. The temperatures 150oC and 175oC were used for the oxidation study and a 60oC was used for incubation storage. The methanol extracts of all four spices demonstrated significant capability in retaining the DHA and EPA, after subjected to oxidation when compared …

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Xanthene/Benzoxanthene Dyes: Novel Synthetic Metholologies, Applications In Molecular Recognition, Cellular Imaging And The Design Of A Tunable White (Rgb) Light Emitter, Youjun Yang Jan 2007

Xanthene/Benzoxanthene Dyes: Novel Synthetic Metholologies, Applications In Molecular Recognition, Cellular Imaging And The Design Of A Tunable White (Rgb) Light Emitter, Youjun Yang

LSU Doctoral Dissertations

My graduate work has focused on the development of new fluorophore materials towards addressing several interdisciplinary research problems. Selective detection of sialic acid via a boron-amide interaction. Concentration changes of sialic acid can be monitored ratiometrically in the visible region using a boronic acid based chemosensor. The technique shows great promise for the detection of sialic acid, a critical cell surface residue involved in cancer, graft rejection and virulence in certain bacteria. There is no interference from commonly occurring oligosaccharides, aminosugars and most carboxylic acid-containing compounds. Improved synthetic methodology and studies of novel molecular probe architectures. I have developed a …

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When In Rome An Examination Of Women And Political Rhetoric, Christina Grace Juneau Jan 2007

When In Rome An Examination Of Women And Political Rhetoric, Christina Grace Juneau

Honors Capstones

No abstract provided.

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Effect Of Red Imported Fire Ant (Solenopsis Invicta Buren) On The Nesting Success Of Northern Bobwhite (Colinus Virginianus L.), Michael Andrew Seymour Jan 2007

Effect Of Red Imported Fire Ant (Solenopsis Invicta Buren) On The Nesting Success Of Northern Bobwhite (Colinus Virginianus L.), Michael Andrew Seymour

LSU Master's Theses

The Northern Bobwhite (Colinus virginianus L.) has experienced average yearly decline of 3% in the United States from 1966-2005. Factors implicated in decline include habitat destruction, alteration of farm practices, and red imported fire ant (RIFA) (Solenopsis invicta Buren). Effect of RIFA on bobwhites has been a hot topic leading to formation of polarized camps – those who believe RIFA have little effect and those who believe the effect will further threaten the species’ survival. The main objective of this study was to determine if RIFA affect nesting of bobwhites and at what stage in nesting birds are most vulnerable. …

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Quantitative And Spatial Analysis Of The Microscopic Bone Structures Of Deer (Odocoileus Virginianus), Dog (Canis Familiaris), And Pig (Sus Scrofa Domesticus), Zoe Hensley Morris Jan 2007

Quantitative And Spatial Analysis Of The Microscopic Bone Structures Of Deer (Odocoileus Virginianus), Dog (Canis Familiaris), And Pig (Sus Scrofa Domesticus), Zoe Hensley Morris

LSU Master's Theses

Structure and morphology of bone tissue are variable by species. The influence of different factors on structure and morphology is still debated. Qualifying and quantifying these differences are necessary in the evaluation of fragmentary bones in order to identify specific species. To understand the influence of species of origin on the microscopic structure of bone tissue, the influence of developmental and biomechanical forces specific to a skeletal element must also be assessed. This research is a preliminary analysis of the histological bone structures in terms of their area, density and spatial organization. To achieve this research goal, the cross-section of …

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Pathology And Seedling Nutrition Of Spartina Alterniflora (Smooth Cordgrass), Clark Lane Robertson Jan 2007

Pathology And Seedling Nutrition Of Spartina Alterniflora (Smooth Cordgrass), Clark Lane Robertson

LSU Master's Theses

Transplants of Spartina alterniflora Loisel. (smooth cordgrass, Poaceae) are effective in stabilizing and protecting vulnerable coastal wetlands from erosion. However, the expense and labor associated with propagation and transplanting restrict the widespread use of S. alterniflora in coastal restoration and protection projects. As an alternative, seeding of S. alterniflora by aircraft has been proposed as a more useful and economical approach for revegetating denuded marsh sites. However, a period of stalled growth, which lasts for 12 or more weeks, has been observed in smooth cordgrass seedlings, and this increases their susceptibility to being washed away by inundating tides. This stalled …

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Grade Retention In High Stakes And Low Stakes Testing Years, Anna Elizabeth Ball Jan 2007

Grade Retention In High Stakes And Low Stakes Testing Years, Anna Elizabeth Ball

LSU Master's Theses

Recent political calls for an end to social promotion have led to an era in which many states are using high stakes tests to make retention decisions. Several decades of research have shown that retention is not an effective practice academically or socially. Louisiana is one state that has adopted a high stakes testing policy. This study examines a state-wide database to examine the predictors of retention in high stakes and low stakes testing years. Multiple regression analyses, discriminant analyses, and logistic regression analyses were run on data from students in grade 4 through grade 8 in Louisiana. The results …

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The Portrayal Of Science In Children's Television, Tristi Bercegeay Charpentier Jan 2007

The Portrayal Of Science In Children's Television, Tristi Bercegeay Charpentier

LSU Master's Theses

Scholars argue that a scientifically literate public is a requirement for a democracy. Children are watching television more today than ever before, and studies have shown that children learn academically educational content from television. The Children's Television Act of 1990 requires broadcasters to provide educational and informational content for children. This study qualitatively evaluated a sample of 38 children's television programs to obtain a description of the scientific content contained in children's television. The study yielded a large quantity of scientific content, yet the quality of the content left much to be desired. Based on the findings of this study, …

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Pharmaceutical Compounds In Wastewater: Wetland Treatment As A Potential Solution, John R. White, Marco A. Belmont, Chris D. Metcalfe Dec 2006

Pharmaceutical Compounds In Wastewater: Wetland Treatment As A Potential Solution, John R. White, Marco A. Belmont, Chris D. Metcalfe

Faculty Publications

Pharmaceutical compounds are being released into the aquatic environment through wastewater discharge around the globe. While there is limited removal of these compounds within wastewater treatment plants, wetland treatment might prove to be an effective means to reduce the discharge of the compounds into the environment. Wetlands can promote removal of these pharmaceutical compounds through a number of mechanisms including photolysis, plant uptake, microbial degradation, and sorption to the soil. We review relevant laboratory research on these various mechanisms and provide data on the few studies that have examined wetland removal. There is a need to document the degree to …

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Epinecrophylla, A New Genus Of Antwrens (Aves: Passeriformes: Thamnophilidae), Morton L. Isler, Daniela Rodrigues Lacerda, Phyllis R. Isler, Shannon J. Hackett, Kenneth V. Rosenberg, Robb T. Brumfield Dec 2006

Epinecrophylla, A New Genus Of Antwrens (Aves: Passeriformes: Thamnophilidae), Morton L. Isler, Daniela Rodrigues Lacerda, Phyllis R. Isler, Shannon J. Hackett, Kenneth V. Rosenberg, Robb T. Brumfield

Faculty Publications

We offer a new generic name for the stipple-throated assemblage of antwrens (Thamnophilidae) currently placed in the genus Myrmotherula. Molecular studies demonstrated that Myrmotherula is polyphyletic, with the stippled-throated group forming a clade that is not sister to any other currently recognized Myrmotherula species. The stipple-throated assemblage is distinguished morphologically by at least one sex having a black throat stippled white or buffy white combined with a comparatively long, unmarked tail, although three populations considered subspecies have lost one of these characters. The distinct evolution of this assemblage is supported by diagnostic behavioral characters derived from foraging behaviors, vocal repertoires, …

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Geological And Oceanographic Perspectives On Event Bed Formation During Hurricane Katrina, T. R. Keen, Y. Furukawa, S. J. Bentley, R. L. Slingerland, W. J. Teague, J. D. Dykes, C. D. Rowley Dec 2006

Geological And Oceanographic Perspectives On Event Bed Formation During Hurricane Katrina, T. R. Keen, Y. Furukawa, S. J. Bentley, R. L. Slingerland, W. J. Teague, J. D. Dykes, C. D. Rowley

Faculty Publications

Storm deposits in ancient shelf sediments typically form thick sequences of interbedded sand and mud deposited during shoreline regression, whereas modern shelf sediments are generally thin veneers deposited during shoreline transgression. In this paper we present a preliminary comparison between ancient and modern storm beds deposited in these disparate contexts. Hurricane Katrina deposited a storm bed on the Louisiana shelf with a maximum observed thickness of 0.58 m, which thinned to approximately 0.1 m at 200 km west of landfall. This thickness is similar to event beds observed in both ancient and modern sediments. Using data for tropical cyclone landfalls …

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Performance Of The Nzi And Other Traps For Biting Flies In North America, S. Mihok, D. A. Carlson, E. S. Krafsur, L. D. Foil Dec 2006

Performance Of The Nzi And Other Traps For Biting Flies In North America, S. Mihok, D. A. Carlson, E. S. Krafsur, L. D. Foil

Faculty Publications

The performance of Nzi traps for tabanids (Tabanus similis Macquart, T. quinquevittatus Wiedemann, Chrysops aberrans Philip, C. univittatus Macquart, C. cincticornis Walker, Hybomitra lasiophthalma (Macquart)), stable flies (Stomoxys calcitrans Linnaeus) (Diptera: Muscidae) and mosquitoes (Aedes) (Diptera: Culicidae) was investigated at various sites in Canada (Ontario, Alberta) and USA (Iowa, Florida, Louisiana). Traps made from selected fabrics, insect nettings and hand-dyed blue cotton were compared to the African design to provide practical recommendations for temperate environments. Comparisons of substituted materials showed that trap performance was optimal only when traps were made from appropriate fabrics in the colours produced by either copper …

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Rapid Decay Of Tree-Community Composition In Amazonian Forest Fragments, William F. Laurance, Henrique E.M. Nascimento, Susan G. Laurance, Ana Andrade, José E.L.S. Ribeiro, Juan Pablo Giraldo, Thomas E. Lovejoy, Richard Condit, Jerome Chave, Kyle E. Harms, Sammya D'Angelo Dec 2006

Rapid Decay Of Tree-Community Composition In Amazonian Forest Fragments, William F. Laurance, Henrique E.M. Nascimento, Susan G. Laurance, Ana Andrade, José E.L.S. Ribeiro, Juan Pablo Giraldo, Thomas E. Lovejoy, Richard Condit, Jerome Chave, Kyle E. Harms, Sammya D'Angelo

Faculty Publications

Forest fragmentation is considered a greater threat to vertebrates than to tree communities because individual trees are typically long-lived and require only small areas for survival. Here we show that forest fragmentation provokes surprisingly rapid and profound alterations in Amazonian tree-community composition. Results were derived from a 22-year study of exceptionally diverse tree communities in 40 1-ha plots in fragmented and intact forests, which were sampled repeatedly before and after fragment isolation. Within these plots, trajectories of change in abundance were assessed for 267 genera and 1,162 tree species. Abrupt shifts in floristic composition were driven by sharply accelerated tree …

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Sines Of A Nearly Perfect Character, David A. Ray, Jinchuan Xing, Abdel Halim Salem, Mark A. Batzer Dec 2006

Sines Of A Nearly Perfect Character, David A. Ray, Jinchuan Xing, Abdel Halim Salem, Mark A. Batzer

Faculty Publications

Mobile elements have been recognized as powerful tools for phylogenetic and population-level analyses. However, issues regarding potential sources of homoplasy and other misleading events have been raised. We have collected available data for all phylogenetic and population level studies of primates utilizing Alu insertion data and examined them for potentially homoplasious and other misleading events. Very low levels of each potential confounding factor in a phylogenetic or population analysis (i.e., lineage sorting, parallel insertions, and precise excision) were found. Although taxa known to be subject to high levels of these types of events may indeed be subject to problems when …

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