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Control Of High-Order Harmonic Emission Using Attosecond Pulse Trains, J. Biegert, A. Heinrich, C. P. Hauri, W. Kornelis, P. Schlup, M. P. Anscombe, M. B. Gaarde, K. J. Schafer, U. Keller Jan 2006

Control Of High-Order Harmonic Emission Using Attosecond Pulse Trains, J. Biegert, A. Heinrich, C. P. Hauri, W. Kornelis, P. Schlup, M. P. Anscombe, M. B. Gaarde, K. J. Schafer, U. Keller

Faculty Publications

We show that attosecond pulse trains are a natural tool to control strong field processes such as high-order harmonic generation. Coherently combining an attosecond pulse train with an IR driving field, we predict and experimentally confirm enhancement and spectral narrowing of the harmonic yield at photon energies around 90 eV. The use of an attosecond pulse train to seed the harmonic generation process replaces tunneling ionization with a single-photon ionization step, therefore permitting the manipulation of the time–frequency properties of high-order harmonic generation already at the single-atom level. © 2006 Taylor & Francis Group, LLC.


Whole Genome Computational Comparative Genomics: A Fruitful Approach For Ascertaining Alu Insertion Polymorphisms, Jianxin Wang, Lei Song, M. Katherine Gonder, Sami Azrak, David A. Ray, Mark A. Batzer, Sarah A. Tishkoff, Ping Liang Jan 2006

Whole Genome Computational Comparative Genomics: A Fruitful Approach For Ascertaining Alu Insertion Polymorphisms, Jianxin Wang, Lei Song, M. Katherine Gonder, Sami Azrak, David A. Ray, Mark A. Batzer, Sarah A. Tishkoff, Ping Liang

Faculty Publications

Alu elements are the most active and predominant type of short interspersed elements (SINEs) in the human genome. Recently inserted polymorphic (for presence/absence) Alu elements contribute to genome diversity among different human populations, and they are useful genetic markers for population genetic studies. The objective of this study is to identify polymorphic Alu insertions through an in silico comparative genomics approach and to analyze their distribution pattern throughout the human genome. By computationally comparing the public and Celera sequence assemblies of the human genome, we identified a total of 800 polymorphic Alu elements. We used polymerase chain reaction-based assays to …


Restoration Success Of Backfilling Canals In Coastal Louisiana Marshes, Joseph Baustian, R. Eugene Turner Jan 2006

Restoration Success Of Backfilling Canals In Coastal Louisiana Marshes, Joseph Baustian, R. Eugene Turner

Faculty Publications

The need for effective marsh restoration techniques in Louisiana is a pressing issue as the state continues to lose coastal wetlands. Returning spoil banks to canals, known as backfilling, is an attractive restoration option because it restores marsh, prevents future wetland loss, and is cost effective. The restoration of 30 canals backfilled 20 years ago was examined in this study and compared to restoration success 5 and 10 years after backfilling. Ultimately, the success of backfilling was controlled by the amount of spoil returned to the canal and the position of the canal in the marsh. Up to 95% of …


Reconstructing The Development Of Eutrophication In Louisiana Salt Marshes, M L. Parsons, Q Dortch, R. Eugene Turner, N R. Rabalais, M L. Parsons Jan 2006

Reconstructing The Development Of Eutrophication In Louisiana Salt Marshes, M L. Parsons, Q Dortch, R. Eugene Turner, N R. Rabalais, M L. Parsons

Faculty Publications

We collected sediment cores from three salt marsh ponds in coastal Louisiana to test the usefulness of proxies of eutrophication. One-centimeter increments of Pb-210- and Cs-137-dated sediment were analyzed for diatoms, pigments (phaeophytin and chlorophyll a), biogenic silica, percentage organic matter, percentage carbon, and percentage nitrogen. Both sediment chlorophyll a and a diatom-based trophic index (TI) were significantly and positively correlated with riverine or local nutrient indices. Two diatom species, Amphora copulata Giffen and Navicula yarrensis Grunow, were significantly and negatively correlated with riverine and local nutrient indices. These results suggest that these variables can be used as potential indicators …


Paleo-Indicators And Water Quality Change In The Charlotte Harbor Estuary (Florida), R. Eugene Turner, N N. Rabalais, B Fry, N Atilla, J M. Lee, C Normandeau, T A. Oswald, E M. Swenson, D A. Tomasko Jan 2006

Paleo-Indicators And Water Quality Change In The Charlotte Harbor Estuary (Florida), R. Eugene Turner, N N. Rabalais, B Fry, N Atilla, J M. Lee, C Normandeau, T A. Oswald, E M. Swenson, D A. Tomasko

Faculty Publications

We reconstructed water quality changes for 1800 to 2000 in Charlotte Harbor (Florida), a shallow subtropical estuary, by using a suite of biological and geochemical proxies in dated sediments collected in the region of a present day, midsummer hypoxic zone. The declining freshwater loading into the estuary from 1931 to the 1980s is not the probable causal agent encouraging the appearance or expansion of a hypoxia zone (measuring up to 90 km(2) in summer). Rather, the reconstructed trends in nitrogen loading indicate increased phytoplankton production has likely caused a decline in bottom water oxygen concentrations. Sedimentary biogenic silica (BSi), carbon, …


Oxygen Depletion In The Gulf Of Mexico Adjacent To The Mississippi River, Nancy N. Rabalais, R. Eugene Turner Jan 2006

Oxygen Depletion In The Gulf Of Mexico Adjacent To The Mississippi River, Nancy N. Rabalais, R. Eugene Turner

Faculty Publications

The seasonal formation of a bottom water layer severely depleted in dissolved oxygen has become a perennial occurrence on the Louisiana continental shelf adjacent to the Mississippi River system. Dramatic changes have occurred in this coastal ecosystem in the last half of the 20th century as the loads of dissolved inorganic nitrogen tripled. There are increases in primary production, shifts in phytoplankton community composition, changes in trophic interactions, and worsening severity of hypoxia. The hypoxic conditions (dissolved oxygen less than 2 mg l-1) cover up to 22,000 km2 of the seabed in mid-summer. Dissolved oxygen concentrations seldom decrease to anoxia, …


Leaf Gas Exchange Characteristics Of Three Neotropical Mangrove Species In Response To Varying Hydroperiod, Ken W. Krauss, Robert R. Twilley, Thomas W. Doyle, Emile S. Gardiner Jan 2006

Leaf Gas Exchange Characteristics Of Three Neotropical Mangrove Species In Response To Varying Hydroperiod, Ken W. Krauss, Robert R. Twilley, Thomas W. Doyle, Emile S. Gardiner

Faculty Publications

We determined how different hydroperiods affected leaf gas exchange characteristics of greenhouse-grown seedlings (2002) and saplings (2003) of the mangrove species Avicennia germinans (L.) Stearn., Laguncularia racemosa (L.) Gaertn. f., and Rhizophora mangle L. Hydroperiod treatments included no flooding (unflooded), intermittent flooding (intermittent), and permanent flooding (flooded). Plants in the intermittent treatment were measured under both flooded and drained states and compared separately. In the greenhouse study, plants of all species maintained different leaf areas in the contrasting hydroperiods during both years. Assimilation-light response curves indicated that the different hydroperiods had little effect on leaf gas exchange characteristics in either …


Gumbo Yearbook, Class Of 2006, Louisiana State University And Agricultural And Mechanical College Jan 2006

Gumbo Yearbook, Class Of 2006, Louisiana State University And Agricultural And Mechanical College

Gumbo Yearbook

The Gumbo yearbook chronicles the entire academic year at LSU. In words and especially photos, the Gumbo shows the people, places, and events that make each year unique. In addition to formal portraits of schools and departments, the book contains hundreds of snapshots of students with their friends and dozens of pages showcasing organizations.


Temperature Dependence And Thermodynamics Of Klenow Polymerase Binding To Primed-Template Dna, Kausiki Datta, Andy J. Wowor, Allison J. Richard, Vince J. Licata Jan 2006

Temperature Dependence And Thermodynamics Of Klenow Polymerase Binding To Primed-Template Dna, Kausiki Datta, Andy J. Wowor, Allison J. Richard, Vince J. Licata

Faculty Publications

DNA binding of Klenow polymerase has been characterized with respect to temperature to delineate the thermodynamic driving forces involved in the interaction of this polymerase with primed-template DNA. The temperature dependence of the binding affinity exhibits distinct curvature, with tightest binding at 25-30°C. Nonlinear temperature dependence indicates Klenow binds different primed-template constructs with large heat capacity (ΔCp) values (-870 to -1220 cal/mole K) and thus exhibits large temperature dependent changes in enthalpy and entropy. Binding is entropy driven at lower temperatures and enthalpy driven at physiological temperatures. Large negative ΔCp values have been proposed to be a 'signature' of site-specific …


Plasmid-Mediated High-Level Gentamicin Resistance Among Enteric Bacteria Isolated From Pet Turtles In Louisiana, María Alejandra Díaz, Richard Kent Cooper, Axel Cloeckaert, Ronald John Siebeling Jan 2006

Plasmid-Mediated High-Level Gentamicin Resistance Among Enteric Bacteria Isolated From Pet Turtles In Louisiana, María Alejandra Díaz, Richard Kent Cooper, Axel Cloeckaert, Ronald John Siebeling

Faculty Publications

The sale of small turtles is banned by the Food and Drug Administration from the U.S. market due to concerns about their excretion of Salmonella spp. To produce a safe pet for the export market, the Louisiana pet turtle industry uses gentamicin sulfate baths (1,000 μg/ml) to eradicate Salmonella spp. from turtle eggs. In 1999, we analyzed bacterial samples recovered from turtle farms and found that strains of Salmonella enterica subsp. arizonae and other bacteria, such as Enterobacter cloacae, Citrobacter freundii, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia, were resistant to high concentrations of gentamicin (>2,000 μg/ml) and to other aminoglycosides. …


Sequence Variation In The Coding Region Of The Melanocortin-1 Receptor Gene (Mc1r) Is Not Associated With Plumage Variation In The Blue-Crowned Manakin (Lepidothrix Coronata), Z. A. Cheviron, Shannon J. Hackett, Robb T. Brumfield Jan 2006

Sequence Variation In The Coding Region Of The Melanocortin-1 Receptor Gene (Mc1r) Is Not Associated With Plumage Variation In The Blue-Crowned Manakin (Lepidothrix Coronata), Z. A. Cheviron, Shannon J. Hackett, Robb T. Brumfield

Faculty Publications

Avian plumage traits are the targets of both natural and sexual selection. Consequently, genetic changes resulting in plumage variation among closely related taxa might represent important evolutionary events. The molecular basis of such differences, however, is unknown in most cases. Sequence variation in the melanocortin-1 receptor gene (MC1R) is associated with melanistic phenotypes in many vertebrate taxa, including several avian species. The blue-crowned manakin (Lepidothrix coronata), a widespread, sexually dichromatic passerine, exhibits striking geographic variation in male plumage colour across its range in southern Central America and western Amazonia. Northern males are black with brilliant blue crowns whereas southern males …


Louisiana Agriculture Winter, 2006, Lsu Agcenter Jan 2006

Louisiana Agriculture Winter, 2006, Lsu Agcenter

Louisiana Agriculture

No abstract provided.


Phytochrome Genes In Higher Plants: Structure,Expression, And Evolution, Robert A. Sharrock, Sarah Mathews Jan 2006

Phytochrome Genes In Higher Plants: Structure,Expression, And Evolution, Robert A. Sharrock, Sarah Mathews

Faculty Publications

© 2006 Springer. All Rights Reserved. Phytochromes play critical roles in monitoring light quantity, quality, and periodicity in plants and they relay this photosensory information to a large number of signaling pathways that regulate plant growth and development. Given these complex functions, it is not surprising that the phytochrome apoproteins are encoded by small multigene families and that different forms of phytochrome regulate different aspects of photomorphogenesis. Over the course of the last decade, progress has been made in defining the number, molecular properties, and biological activities of the photoreceptors that constitute a plant R/FR sensing system. This chapter summarizes …


Relations Between Chinese Mothers' Parenting Practices And Social Withdrawal In Early Childhood, Larry J. Nelson, Craig H. Hart, Bo Wu, Chongming Yang, Susanne Olsen Roper, Shenghua Jin Jan 2006

Relations Between Chinese Mothers' Parenting Practices And Social Withdrawal In Early Childhood, Larry J. Nelson, Craig H. Hart, Bo Wu, Chongming Yang, Susanne Olsen Roper, Shenghua Jin

Faculty Publications

Researchers have identified specific parenting practices used by parents of preschoolers in mainland China (e.g., physical coercion, overprotection, shaming, directiveness, encouragement of modesty). Some of the intrusive practices have been linked to social withdrawal in western societies (e.g., United States, Canada). It seemed important to examine these associations in China because recent research suggests that young Chinese children who exhibit wariness in peer settings may be at risk for negative outcomes such as peer rejection. Therefore, the purpose of this study was to examine the relation between Chinese parenting practices and preschoolers' social withdrawal. Mothers of preschool-age children from mainland …


A Spectrum Of Pcsk9 Alleles Contributes To Plasma Levels Of Low-Density Lipoprotein Cholesterol, Ingrid K. Kotowski, Alexander Pertsemlidis, Amy Luke, Richard S. Cooper, Gloria L. Vega, Jonathan C. Cohen, Helen H. Hobbs Jan 2006

A Spectrum Of Pcsk9 Alleles Contributes To Plasma Levels Of Low-Density Lipoprotein Cholesterol, Ingrid K. Kotowski, Alexander Pertsemlidis, Amy Luke, Richard S. Cooper, Gloria L. Vega, Jonathan C. Cohen, Helen H. Hobbs

Faculty Publications

Selected missense mutations in the proprotein convertase subtilisin/kexin type 9 serine protease gene (PCSK9) cause autosomal dominant hypercholesterolemia, whereas nonsense mutations in the same gene are associated with low plasma levels of low-density lipoprotein cholesterol (LDL-C). Here, DNA sequencing and chip-based oligonucleotide hybridization were used to determine whether other sequence variations in PCSK9 contribute to differences in LDL-C levels. The coding regions of PCSK9 were sequenced in the blacks and whites from the Dallas Heart Study (n = 3,543) who had the lowest (percentile) and highest (>95 th percentile) plasma levels of LDL-C. Of the 17 missense variants identified, …


Comparative Susceptibility Of Sweetpotato Weevil (Coleoptera: Brentidae) To Selected Insecticides, Tara P. Smith, Abner M. Hammond Jan 2006

Comparative Susceptibility Of Sweetpotato Weevil (Coleoptera: Brentidae) To Selected Insecticides, Tara P. Smith, Abner M. Hammond

Faculty Publications

The response of sweetpotato weevil, Cylas formicarius (F.) (Coleoptera: Brentidae), to insecticides used for its control was tested in laboratory bioassays. A glass vial bioassay technique was used to determine the susceptibility of two cohorts of sweetpotato weevil to selected insecticides. Vials were treated with methyl parathion, bifenthrin, cyfluthrin, carbaryl, and phosmet. Sweetpotato weevils demonstrated a mortality response to increasing concentrations of all insecticides tested, and our results indicated decreases in susceptibility of the Louisiana cohort of sweetpotato weevil compared with the Texas cohort for all insecticides tested. Methyl parathion was the most toxic chemical tested for both cohorts, followed …


Pilibacter Termitis Gen. Nov., Sp. Nov., A Lactic Acid Bacterium From The Hindgut Of The Formosan Subterranean Termite (Coptotermes Formosanus), Dennis T. Higashiguchi, Claudia Husseneder, J. Kenneth Grace, John M. Berestecky Jan 2006

Pilibacter Termitis Gen. Nov., Sp. Nov., A Lactic Acid Bacterium From The Hindgut Of The Formosan Subterranean Termite (Coptotermes Formosanus), Dennis T. Higashiguchi, Claudia Husseneder, J. Kenneth Grace, John M. Berestecky

Faculty Publications

A previously undescribed anaerobic, heterofermentative, non-spore-forming, Gram-positive rod was isolated from the hindgut of the Formosan subterranean termite Coptotermes formosanus Shiraki. The DNA G + C content of this bacterium was 37.8 mol%. Sequence analysis of the 16S rRNA gene revealed that this organism is related to, but distinct from, several genera of lactic acid bacteria, principally several species of the genus Enterococcus. Phenotypic traits that serve to separate this organism from related genera include high levels of the cellular fatty acid C18:1ω9c and the production of ethanol along with lactic acid as fermentation products. Based on the collected phylogenetic …


Genetic Analysis Of Colony And Population Structure Of Three Introduced Populations Of The Formosan Subterranean Termite (Isoptera: Rhinotermitidae) In The Continental United States, Edward L. Vargo, Claudia Husseneder, David Woodson, Michael G. Waldvogel, J. Kenneth Grace Jan 2006

Genetic Analysis Of Colony And Population Structure Of Three Introduced Populations Of The Formosan Subterranean Termite (Isoptera: Rhinotermitidae) In The Continental United States, Edward L. Vargo, Claudia Husseneder, David Woodson, Michael G. Waldvogel, J. Kenneth Grace

Faculty Publications

The Formosan subterranean termite, Coptotermes formosanus Shiraki, is a major invasive pest species in many parts of the world. We compared the colony breeding system and population genetic structure in three introduced populations in the continental United States: Charleston, SC; City Park, New Orleans, LA; and Rutherford County, NC. Based on worker genotypes at 12 microsatellite loci, we found that colonies were mainly genetically distinct entities consisting of either simple families headed by monogamous pairs of reproductives or extended families containing multiple neotenic (replacement) reproductives descended from simple families. Populations varied from 48% simple families in Charleston to 82% simple …


Dating Paleosol And Animal Remains In Loess Deposits, H. C. Zhang, B. Li, M. S. Yang, G. L. Lei, H. Ding, Jie Niu, H. F. Fan, W. X. Zhang, F. Q. Chang Jan 2006

Dating Paleosol And Animal Remains In Loess Deposits, H. C. Zhang, B. Li, M. S. Yang, G. L. Lei, H. Ding, Jie Niu, H. F. Fan, W. X. Zhang, F. Q. Chang

Faculty Publications

Accurate and reliable dating of paleosols, animal remains, and artifacts is of crucial importance in reconstructing environmental change and understanding the interrelationship between human activities and natural environments. Dating different materials in the same sample can help resolve problems such as soil carbon sources and carbon storage state. Conventional radiocarbon dating of soil (inorganic and organic matter) and accelerator mass spectrometry (AMS) dating of animal remains (fossil bones and teeth) result in different ages for materials from the same sample position in a typical loess section at Xinglong Mountain, Yuzhong County, Gansu Province in NW China. Inorganic matter is ∼3400 …


Human Genomic Deletions Mediated By Recombination Between Alu Elements, Shurjo K. Sen, Kyudong Han, Jianxin Wang, Jungnam Lee, Hui Wang, Pauline A. Callinan, Matthew Dyer, Richard Cordaux, Ping Liang, Mark A. Batzer Jan 2006

Human Genomic Deletions Mediated By Recombination Between Alu Elements, Shurjo K. Sen, Kyudong Han, Jianxin Wang, Jungnam Lee, Hui Wang, Pauline A. Callinan, Matthew Dyer, Richard Cordaux, Ping Liang, Mark A. Batzer

Faculty Publications

Recombination between Alu elements results in genomic deletions associated with many human genetic disorders. Here, we compare the reference human and chimpanzee genomes to determine the magnitude of this recombination process in the human lineage since the human-chimpanzee divergence ∼6 million years ago. Combining computational data mining and wet-bench experimental verification, we identified 492 human-specific deletions (for a total of ∼400 kb) attributable to this process, a significant component of the insertion/deletion spectrum of the human genome. The majority of the deletions (295 of 492) coincide with known or predicted genes (including 3 that deleted functional exons, as compared with …


Introduction: Self-Organization In Nonequilibrium Chemical Systems, Irving R. Epstein, John A. Pojman, Oliver Steinbock Jan 2006

Introduction: Self-Organization In Nonequilibrium Chemical Systems, Irving R. Epstein, John A. Pojman, Oliver Steinbock

Faculty Publications

The field of self-organization in nonequilibrium chemical systems comprises the study of dynamical phenomena in chemically reacting systems far from equilibrium. Systematic exploration of this area began with investigations of the temporal behavior of the Belousov-Zhabotinsky oscillating reaction, discovered accidentally in the former Soviet Union in the 1950s. The field soon advanced into chemical waves in excitable media and propagating fronts. With the systematic design of oscillating reactions in the 1980s and the discovery of Turing patterns in the 1990s, the scope of these studies expanded dramatically. The articles in this Focus Issue provide an overview of the development and …


School Of Renewable Natural Resources Newsletter, Fall 2006, Louisiana State University And Agricultural & Mechanical College Jan 2006

School Of Renewable Natural Resources Newsletter, Fall 2006, Louisiana State University And Agricultural & Mechanical College

Research Matters & RNR Newsletters

The annual newsletter from the School of Renewable Natural Resources was a publication which aimed to update and entertain interested readers with the news and research from RNR faculty, students and staff.


Hume, Comte, And The Religion Of Le Grand Etre, Darian C. Debolt Jan 2006

Hume, Comte, And The Religion Of Le Grand Etre, Darian C. Debolt

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.


David Hume, "Ofthe Standard Of Taste," And Esthetic Theory, James W. Mock Jan 2006

David Hume, "Ofthe Standard Of Taste," And Esthetic Theory, James W. Mock

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.


Hume And The End Of Design, Michael F. Patton Jr. Jan 2006

Hume And The End Of Design, Michael F. Patton Jr.

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.


"Of That Rank That Is Meanest And Most Despised Of All" Victorian Romany Studies And The Recovery Of John Bunyan's "Gypsy' Origins, Mary Burke Jan 2006

"Of That Rank That Is Meanest And Most Despised Of All" Victorian Romany Studies And The Recovery Of John Bunyan's "Gypsy' Origins, Mary Burke

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.


Quantum Interpretations, A. R.P. Rau Jan 2006

Quantum Interpretations, A. R.P. Rau

Faculty Publications

Difficulties and discomfort with the interpretation of quantum mechanics are due to differences in language between it and classical physics. Analogies to the special theory of relativity, which also required changes in the basic world-view and language of nonrelativistic classical mechanics, may help in absorbing the changes called for by quantum physics. There is no need to invoke extravagances such as the many-worlds interpretation or specify a central role for consciousness or neural microstructures. The simple, but basic, acceptance that what is meant by the state of a physical system is different in quantum physics from what it is in …


Occurrence Of Freshwater Bivalves In A Chronically Hypoxic Coastal Stream In Louisiana, Usa, Michael D. Kaller, William E. Kelso Jan 2006

Occurrence Of Freshwater Bivalves In A Chronically Hypoxic Coastal Stream In Louisiana, Usa, Michael D. Kaller, William E. Kelso

Faculty Publications

We sampled bivalves in Mill Creek, a low-gradient stream in southwestern Louisiana, and found a comparatively diverse assemblage in a disturbed, chronically hypoxic stream. We found few bivalves in April, nearly 1,700 in June, but only 170 in September. Species richness varied temporally with one species in April, eight species in June, and three species in September. We suggest dissolved oxygen level plays a particularly important role in bivalve community dynamics in this stream. © 2006, Copyright Taylor & Francis Group, LLC.


Avian Influenza (H5n1) And The Evolutionary And Social Ecology Of Infectious Disease Emergence, Durrell D. Kapan, Shannon N. Bennett, Brett N. Ellis, Jefferson Fox, Nancy D. Lewis, James H. Spencer, Sumeet Saksena, Bruce A. Wilcox Jan 2006

Avian Influenza (H5n1) And The Evolutionary And Social Ecology Of Infectious Disease Emergence, Durrell D. Kapan, Shannon N. Bennett, Brett N. Ellis, Jefferson Fox, Nancy D. Lewis, James H. Spencer, Sumeet Saksena, Bruce A. Wilcox

Faculty Publications

No abstract provided.


Case Study: Cholera, Edward Laws Jan 2006

Case Study: Cholera, Edward Laws

Faculty Publications

No abstract provided.