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Articles 2221 - 2250 of 3347

Full-Text Articles in Life Sciences

An Assessment Of High School Coaches Knowledge Of Sport-Related Concussion, Erin M. O'Donoghue Apr 2007

An Assessment Of High School Coaches Knowledge Of Sport-Related Concussion, Erin M. O'Donoghue

Human Movement Studies & Special Education Theses & Dissertations

Sport-related concussion is a common occurrence in high-risk sports and can occur during participation in all sports. The purpose of this study was to assess the knowledge base high school athletic coaches possess about concussion signs and symptoms in regards to recognition, management, and prevention of this condition. A 25 question demographic questionnaire was used to gather background information and a 24 question multiple-choice assessment was used to determine knowledge of recognition, management, and prevention of sport-related concussion. A panel of eight experts in the fields of sport-related concussion and/or survey research reviewed and modified the survey instrument, which were …

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Behavioral Enhancement Of Onshore Transport By Postlarval Caribbean Spiny Lobster (Panulirus Argus), Jason Seth Goldstein Apr 2007

Behavioral Enhancement Of Onshore Transport By Postlarval Caribbean Spiny Lobster (Panulirus Argus), Jason Seth Goldstein

Biological Sciences Theses & Dissertations

The onshore transport of meroplanktonic marine larvae or postlarvae is often complex, involving both active (i.e., behavior, swimming) and passive (i.e., oceanographic elements) transport mechanisms. Behaviors that modify passive transport have presumably evolved to situate larvae in settlement habitats where survival is enhanced. Active transport mechanisms have not been described for the puerulus postlarvae of any species of spiny lobster, despite their extraordinary mobility and known preference for specific settlement habitats. In the Florida Keys, for example, Caribbean spiny lobster (Panulirus argus) pueruli travel from oceanic waters into coastal areas where they settle within bushy, red macroalgae. I …

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Effects Of Elevated Atmospheric Co2 On Root Dynamics, Biomass And Architecture In A Scrub-Oak Ecosystem At Kennedy Space Center, Florida, Daniel Benjamin Stover Apr 2007

Effects Of Elevated Atmospheric Co2 On Root Dynamics, Biomass And Architecture In A Scrub-Oak Ecosystem At Kennedy Space Center, Florida, Daniel Benjamin Stover

Biological Sciences Theses & Dissertations

A major gap in whole-plant ecology lies with our understanding of root system growth, function and distribution. Large belowground structures, in addition to fine roots, are of particular interest because of their role in carbon sequestration. Non-destructive methods, including ground-penetrating radar (GPR) and minirhizotron observation tubes, were used to investigate effects of elevated CO2 on root biomass, dynamics (productivity, mortality, and turnover), root persistence and architecture in a fire dominated scrub-oak ecosystem. Open-top chambers have been exposed to elevated atmospheric CO2 for the past eleven years at Kennedy Space Center, Florida. No significant sustained CO2 treatment effects …

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The Effect Of Three Foot Orthoses On Plantar Pressure Under The First Metatarsophalangeal Joint Of Pes Planus Foot Type During Standing And Slow Running, Lacey Ann Nordsiden Apr 2007

The Effect Of Three Foot Orthoses On Plantar Pressure Under The First Metatarsophalangeal Joint Of Pes Planus Foot Type During Standing And Slow Running, Lacey Ann Nordsiden

Human Movement Studies & Special Education Theses & Dissertations

The purpose of this study was to examine the effect of three different foot orthoses on plantar pressure under the first metatarsophalangeal joint during standing and slow running. Twenty physically active participants, 12 males (19.7±1.3 years, 181.5±6.3cm, 83.6±12.3kg) and 8 females (20.8±1.5 years, 172.7±11.2cm, 69.9±14.2kg) with navicular drop greater than 10mm, no history of surgery to the lower extremity, and no history of pain or injury to the 1st metatarsophalangeal joint in the past six months volunteered for the study. Each subject performed standing and slow running tasks with four different orthosis conditions: no orthosis, metatarsal dome, U-shaped orthosis, and …

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Down-Regulation Of Natural Killer Cell Activation In Response To Influenza Virus In Older Adults, Yu Jing Apr 2007

Down-Regulation Of Natural Killer Cell Activation In Response To Influenza Virus In Older Adults, Yu Jing

Theses and Dissertations in Biomedical Sciences

Immune senescence contributes to influenza-associated high mortality and morbidity and reduced vaccine efficacy in elderly people. Type I T cell (Thl)-mediated immunity plays a significant role in Immune responses to influenza infection and vaccination. Natural killer (NK) cells secrete significant amount of IFN-7 , a hallmark Thl cytokine, in response to influenza infection. How aging influences human NK cell IFN-7 production in response to influenza virus has not been well documented. In this study we employed human peripheral blood mononuclear cells (PBMC) and performed intracellular cytokine staining and flow cytometry primarily to investigate how aging influences NK cell activation with …

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Interactions Between Phytoplankton And Bacteria In The Uptake Of Organic Compounds, Andrea Michel Rocha Apr 2007

Interactions Between Phytoplankton And Bacteria In The Uptake Of Organic Compounds, Andrea Michel Rocha

OES Theses and Dissertations

The most common methods for estimating bacterial productivity are [3H]-leucine and [3H]-thymidine incorporation. Uptake of these compounds has been attributed primarily to bacteria; however, because dissolved organic nitrogen may be an important N source for some phytoplankton, the use of these compounds to estimate bacterial productivity needs to be reexamined. In order to ascertain whether phytoplankton could compete with bacteria on relevant timescales and thereby bias bacterial productivity estimates in estuaries, I examined the ability of cultured phytoplankton and size-fractionated natural populations to take up leucine and thymidine in systems seasonally dominated by phytoplankton mixotrophs. In …

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Staphylococcal Cassette Chromosome Mec And Panton-Valentine Leukocidin Characterization Of Methicillin-Resistant Staphylococcus Aureus Clones, Shannon M. Moroney, Loree C. Heller, Jesse Arbuckle, Monica Talavera, Ray H. Widen Mar 2007

Staphylococcal Cassette Chromosome Mec And Panton-Valentine Leukocidin Characterization Of Methicillin-Resistant Staphylococcus Aureus Clones, Shannon M. Moroney, Loree C. Heller, Jesse Arbuckle, Monica Talavera, Ray H. Widen

Bioelectrics Publications

Staphylococcal cassette chromosome mec (SCCmec) types and Panton-Valentine leukocidin (PVL) gene carriage were compared among suspected community-associated methicillin-resistant Staphylococcus aureus MRSA (CA-MRSA) and health care-associated MRSA (HA-MRSA) isolates. CA-MRSA isolates carried the SCCmec type IV complex, and most were PVL positive. The HA-MRSA isolates carried the SCCmec type II complex and did not harbor the PVL genes.

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Optimization Of Cutaneous Electrically Mediated Plasmid Dna Delivery Using Novel Electrode, L. C. Heller, M. J. Jaroszeski, D. Coppola, A. N. Mccray, J. Hickey, R. Heller Feb 2007

Optimization Of Cutaneous Electrically Mediated Plasmid Dna Delivery Using Novel Electrode, L. C. Heller, M. J. Jaroszeski, D. Coppola, A. N. Mccray, J. Hickey, R. Heller

Bioelectrics Publications

The easy accessibility of skin makes it an excellent target for gene transfer protocols. To take advantage of skin as a target for gene transfer, it is important to establish an efficient and reproducible delivery system. Electroporation is an established technique for enhancing plasmid delivery to many tissues in vivo. A critical component of this technique is the electrode configuration. Electroporation parameters were optimized for transgene expression with minimal tissue damage with a novel electrode. The highest transgene expression and efficiency of individual cell transformation with minimal damage was produced with eight 150 ms pulses at field strength of …

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The Application Of Electrospray Ionization Coupled To Ultrahigh Resolution Mass Spectrometry For The Molecular Characterization Of Natural Organic Matter, Rachel L. Sleighter, Patrick G. Hatcher Jan 2007

The Application Of Electrospray Ionization Coupled To Ultrahigh Resolution Mass Spectrometry For The Molecular Characterization Of Natural Organic Matter, Rachel L. Sleighter, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Mass spectrometry has recently played a key role in the understanding of natural organic matter (NOM) by providing molecular-level details about its composition. NOM, a complex assemblage of organic molecules present in natural waters and soils/sediments, has the ability to bind and transport anthropogenic materials. An improved understanding of its composition is crucial in order to understand how pollutants interact with NOM and how NOM cycles through global carbon cycles. In the past, low-resolution (> 3000) mass analyzers have offered some insights into the structure of NOM, but emerging ultrahigh resolution (> 200000) techniques such as electrospray ionization (ESI) coupled …

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Amurocrangonyx, A New Genus Of Subterranean Amphipod (Crangonyctidae) From The Russian Far East, With A Redescription Of The Poorly Known Crangonyx Arsenjevi And Comments On Biogeographic Relationships, Dmitry A. Sidorav, John R. Holsinger Jan 2007

Amurocrangonyx, A New Genus Of Subterranean Amphipod (Crangonyctidae) From The Russian Far East, With A Redescription Of The Poorly Known Crangonyx Arsenjevi And Comments On Biogeographic Relationships, Dmitry A. Sidorav, John R. Holsinger

Biological Sciences Faculty Publications

Amurocrangonyx n. gen. is described on the basis of recently collected specimens of Crangonyx arsenjevi (Derzhavin, 1927), a very poorly known subterranean amphipod crustacean originally described from springs in the Khor River basin of the Ussury River drainage in the Russian Far East. The species is redescribed from specimens obtained from the type-locality, Orekhovy spring, and a neotype is designated. A careful examination of the newly acquired material, although closely similar morphologically to Crangonyx, suggests that it represents a new genus in Crangonyctidae. However, determination of the precise phylogeographic relationship of Amurocrangonyx to Crangonyx or to other crangonyctoid genera …

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Stormwater Influence On Phytoplankton Composition And Dynamics In Lake Joyce, Virginia, Lewis F. Affronti Jr., B. Thomas Duquette Jan 2007

Stormwater Influence On Phytoplankton Composition And Dynamics In Lake Joyce, Virginia, Lewis F. Affronti Jr., B. Thomas Duquette

Virginia Journal of Science

A three year study of Lake Joyce, Virginia revealed relationships between the timing, duration, and amount of stormwater runoff and phytoplankton abundance and composition. Major phytoplankton taxa were identified and cyanophytes dominanted during periods of decreased rainwater input and increased lake water retention times. Increased freshwater input was associated with the growth of a diverse assemblage of both chlorophytes and diatoms. Phytoplankton dynamics as a result of significant rain events (i.e., hurricanes Floyd and Irene, 1999) were documented and specific taxa involved in nuisance algal blooms were identified.

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On A Multinational Assessment Of Rotavirus Disease In Europe, David O. Matson Jan 2007

On A Multinational Assessment Of Rotavirus Disease In Europe, David O. Matson

Community & Environmental Health Faculty Publications

Rotaviruses were discovered in the 1960s in animals and in the 1970s in humans; the latter discovery was made by an intrepid group who performed duodenal biopsies on children with acute gastroenteritis (AGE) [1]. By the late 1970s, data already clearly indicated that rotavirus was the cause of the annual winter peak of AGE affecting young children, as well as a frequent cause of severe gastroenteritis in various animal species (e.g., [2–5]). Use of the retrospectroscope clarified or left as tantalizing the suggestion that rotaviruses were the cause of the annual “winter vomiting syndrome” first described in children in 1910 …

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Potential For Stimulating Host Anti-Tumor Immune Response Via Rnai-Mediated Local Foxp3 Knockdown, N. Klaiber Jan 2007

Potential For Stimulating Host Anti-Tumor Immune Response Via Rnai-Mediated Local Foxp3 Knockdown, N. Klaiber

Chemistry & Biochemistry Faculty Publications

Neoplastic growths represent a unique challenge for the host immune system. As they are indeed derived from self, many of the same mechanisms operating to prevent autoimmunity also provide an umbrella beneath which malignant cells are free to proliferate.1 Central among these immune regulatory boundaries are an influential subset of lymphocytes known as T regs. Hypothesized to exist decades ago, yet eluding definitive characterization until relatively recently, T regs have been demonstrated to play a crucial role in the proper functioning of the immune system as a whole. They may also, however, represent one of the primary obstacles to successful …

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Bioelectric Effects Of Intense Nanosecond Pulses, Karl H. Schoenbach, Barbara Y. Hargrave, Ravindra P. Joshi, Juergen F. Kolb, Richard Nuccitelli, Christopher J. Osgood, Andrei G. Pakhomov, Michael W. Stacey, James R. Swanson, Jody A. White, Shu Xiao, Jue Zhang, Stephen J. Beebe, Peter F. Blackmore, E. Stephen Buescher Jan 2007

Bioelectric Effects Of Intense Nanosecond Pulses, Karl H. Schoenbach, Barbara Y. Hargrave, Ravindra P. Joshi, Juergen F. Kolb, Richard Nuccitelli, Christopher J. Osgood, Andrei G. Pakhomov, Michael W. Stacey, James R. Swanson, Jody A. White, Shu Xiao, Jue Zhang, Stephen J. Beebe, Peter F. Blackmore, E. Stephen Buescher

Bioelectrics Publications

Electrical models for biological cells predict that reducing the duration of applied electrical pulses to values below the charging time of the outer cell membrane (which is on the order of 100 ns for mammalian cells) causes a strong increase in the probability of electric field interactions with intracellular structures due to displacement currents. For electric field amplitudes exceeding MV/m, such pulses are also expected to allow access to the cell interior through conduction currents flowing through the permeabilized plasma membrane. In both cases, limiting the duration of the electrical pulses to nanoseconds ensures only nonthermal interactions of the electric …

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Mutations In Transmembrane Domains 1, 4 And 9 Of The Plasmodium Falciparum Chloroquine Resistance Transporter Alter Susceptibility To Chloroquine, Quinine And Quinidine, Roland A. Cooper, Kristan D. Lane, Bingbing Deng, Jianbing Mu, Jigar J. Patel, Thomas E. Wellems, Xinzhuan Su, Michael T. Ferdig Jan 2007

Mutations In Transmembrane Domains 1, 4 And 9 Of The Plasmodium Falciparum Chloroquine Resistance Transporter Alter Susceptibility To Chloroquine, Quinine And Quinidine, Roland A. Cooper, Kristan D. Lane, Bingbing Deng, Jianbing Mu, Jigar J. Patel, Thomas E. Wellems, Xinzhuan Su, Michael T. Ferdig

Biological Sciences Faculty Publications

Mutations in the Plasmodium falciparum chloroquine (CQ) resistance transporter (PfCRT) can result in verapamil-reversible CQ resistance and altered susceptibility to other antimalarials. PfCRT contains 10 membrane-spanning domains and is found in the digestive vacuole (DV) membrane of intraerythrocytic parasites. The mechanism by which PfCRT mediates CQ resistance is unclear although it is associated with decreased accumulation of drug within the DV. On the permissive background of the P. falciparum 106/1(K76) parasite line, we used single-step drug selection to generate isogenic clones containing unique pfcrt point mutations that resulted in amino acid changes in PfCRT transmembrane domains 1 (C72R, K76N, K76I …

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Tissue And Life Stage Distribution Of A Defensin-Like Gene In The Lone Star Tick Amblyomma Americanum, S. Michelle Todd, Daniel E. Sonenshine, Wayne L. Hynes Jan 2007

Tissue And Life Stage Distribution Of A Defensin-Like Gene In The Lone Star Tick Amblyomma Americanum, S. Michelle Todd, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

The transcript sequence of the Amblyomma americanum Linnaeus (Acari: Ixodidae) defensin, termed amercin (amn), was ascertained and a 219-bp amn coding region identified. The gene encodes a 72-amino acid prepropeptide with a putative 37-amino acid mature peptide. This gene shows little similarity to either of the defensins from Amblyomma hebraeum Koch, the only other Amblyomma species for which a defensin has been described. Sequence comparisons with other tick defensins reveal amn to be shorter (6 bp or 2 amino acids) than the Ixodes scapularis Linnaeus (Acari: Ixodidae) and Dermacentor variabilis (Say) (Acari: Ixodidae) defensin sequences. The amercin prepropeptide …

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In Vivo Imaging Of Transport And Biocompatibility Of Single Silver Nanoparticles In Early Development Of Zebrafish Embryos, Kerry J. Lee, Prakash D. Nallathamby, Lauren M. Browning, Christopher J. Osgood, Xiao-Hong Nancy Xu Jan 2007

In Vivo Imaging Of Transport And Biocompatibility Of Single Silver Nanoparticles In Early Development Of Zebrafish Embryos, Kerry J. Lee, Prakash D. Nallathamby, Lauren M. Browning, Christopher J. Osgood, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Real-time study of the transport and biocompatibility of nanomaterials in early embryonic development at single-nanoparticle resolution can offer new knowledge about the delivery and effects of nanomaterials in vivo, and provide new insights into molecular transport mechanisms in developing embryos. In this study, we directly characterized the transport of single silver nanoparticles into an in vivo model system (zebrafish embryos) and investigated their effects on early embryonic development at single-nanoparticle resolution in real time. We designed highly purified and stable (not aggregated and no photodecomposition) nanoparticles and developed single-nanoparticle optics and in vivo assays to enable the study. We …

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Punking Yoga: Reconstructing Post/Neo/Colonial Fashion And Movement, Tara Brabazon Jan 2007

Punking Yoga: Reconstructing Post/Neo/Colonial Fashion And Movement, Tara Brabazon

Reconstruction: Studies in Contemporary Culture

The branded clothes worn through sporting and fitness activities confirm that any movement, practice or behaviour that seems transgressive of heteronormative masculinity and femininity is also implicated in neo/colonial incorporations and the casualized workforce that is a characteristic of sports clothing manufacture. In an environment washed by the marketing of opposition, resistance is both difficult to define and apply in cultural studies. This paper invokes 'the problem' of resistance while denying the seamless and simple determinations of positive and negative representations. The focus of study is Yogurt Activewear, a company attacking corporatized yoga wear by creating an anti-brand brand. They …

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Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2005, Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman Jan 2007

Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2005, Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman

Status and Trends for Virginia Chesapeake Bay

A marked decline in the water quality of the Chesapeake Bay has occurred over the past several decades. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality. The results of concentrated research efforts in the late 1970s and early 1980s stimulated the establishment of Federal and state directives to better manage the Chesapeake Bay watershed. By way of the …

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Plant Assemblage Structure On Barrier Island ‘Pimple’ Dunes At The Virginia Coast Reserve Long-Term Ecological Research Site, Brett A. Mcmillan Jan 2007

Plant Assemblage Structure On Barrier Island ‘Pimple’ Dunes At The Virginia Coast Reserve Long-Term Ecological Research Site, Brett A. Mcmillan

Biological Sciences Theses & Dissertations

The habitats at the VCR LTER that were the focus of the current study are the Hog Island and Parramore Island 'pimples', small, rounded dunes forming along main dune ridges of the barrier islands. There are distinct plant assemblage zones found on pimples, although most of these dunes are 10–20 m in diameter. Hypotheses of the study were that fresh water availability was a main determinant of differences between assemblages and that pimple size and location would influence diversity and assemblage structure. Research goals were (1) to describe the plant assemblages on pimples, (2) to relate edaphic and geomorphological factors …

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Phytoplankton Productivity In The Tidal Regions Of Four Chesapeake Bay (U.S.A.) Tributaries, Kneeland K. Nesius, Harold G. Marshall, Todd A. Egerton Jan 2007

Phytoplankton Productivity In The Tidal Regions Of Four Chesapeake Bay (U.S.A.) Tributaries, Kneeland K. Nesius, Harold G. Marshall, Todd A. Egerton

Virginia Journal of Science

Monthly and annual phytoplankton productivity rates of four Virginia tidal rivers were determined based on a 12-year monitoring study that included sampling stations from tidal freshwater, oligohaline, and mesohaline regions in these rivers. The mean monthly rates and range at these locations were 5.52 (Dec.) to 175.12 (Aug.) mg C m-3 h-1 for tidal freshwater, 12.21 (Jan.) to 149.90 (May) mg C m-3 h-1 in oligohaline regions, and 16.20 (Jan.) to 151.33 (May) mg C m-3 h-1 for the mesohaline. The estimated mean annual 12 year productivity for the different Virginia river sites in …

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Optimization Of Biomathematical Model Predictions For Cognitive Performance Impairment In Individuals: Accounting For Unknown Traits And Uncertain States In Homeostatic And Circadian Processes, Hans P. A. Van Dongen, Christopher G. Mott, Jen-Kuang Huang, Daniel J. Mollicone, Frederic D. Mckenzie, David F. Dinges Jan 2007

Optimization Of Biomathematical Model Predictions For Cognitive Performance Impairment In Individuals: Accounting For Unknown Traits And Uncertain States In Homeostatic And Circadian Processes, Hans P. A. Van Dongen, Christopher G. Mott, Jen-Kuang Huang, Daniel J. Mollicone, Frederic D. Mckenzie, David F. Dinges

Mechanical & Aerospace Engineering Faculty Publications

Current biomathematical models of fatigue and performance do not accurately predict cognitive performance for individuals with a priori unknown degrees of trait vulnerability to sleep loss, do not predict performance reliably when initial conditions are uncertain, and do not yield statistically valid estimates of prediction accuracy, These limitations diminish their usefulness for predicting the performance of individuals in operational environments. To overcome these 3 limitations, a novel modeling approach was developed, based on the expansion of a statistical technique called Bayesian forecasting. The expanded Bayesian forecasting procedure was implemented in the two-process model of sleep regulation, which has been used …

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Confidence Intervals For Individualized Performance Models, Hans P. A. Van Dongen, Christopher G. Mott, Jen-Kuang Huang, Daniel J. Millicone, Frederic D. Mckenzie, David F. Dinges Jan 2007

Confidence Intervals For Individualized Performance Models, Hans P. A. Van Dongen, Christopher G. Mott, Jen-Kuang Huang, Daniel J. Millicone, Frederic D. Mckenzie, David F. Dinges

Mechanical & Aerospace Engineering Faculty Publications

Commentary on Reifman J; Rajaraman S; Gribok AV. Moving Towards Individualized Performance Models. Sleep 2007;30(9):1081-82.

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An Epidemiological Model Of Rift Valley Fever, Holly D. Gaff, David M. Hartley, Nicole P. Leahy Jan 2007

An Epidemiological Model Of Rift Valley Fever, Holly D. Gaff, David M. Hartley, Nicole P. Leahy

Biological Sciences Faculty Publications

We present and explore a novel mathematical model of the epidemiology of Rift Valley Fever (RVF). RVF is an Old World, mosquito-borne disease affecting both livestock and humans. The model is an ordinary differential equation model for two populations of mosquito species, those that can transmit vertically and those that cannot, and for one livestock population. We analyze the model to find the stability of the disease-free equlibrium and test which model parameters affect this stability most significantly. This model is the basis for future research into the predication of future outbreaks in the Old World and the assessment of …

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Structural Attributes Of The Hypogeous Holoparasite Hydnora Triceps Drège & Meyer (Hydnoraceae), Kushan U. Tennakoon, Jay F. Bolin, Lytton J. Musselman, Erika Maas Jan 2007

Structural Attributes Of The Hypogeous Holoparasite Hydnora Triceps Drège & Meyer (Hydnoraceae), Kushan U. Tennakoon, Jay F. Bolin, Lytton J. Musselman, Erika Maas

Biological Sciences Faculty Publications

The morphology of the hypogeous root holoparasite Hydnora triceps is highly reduced, and as with many holoparasites, the vegetative body is difficult to interpret. The vegetative body of H. triceps has been historically considered a "pilot root" studded with lateral appendages known as "haustorial roots." We found the vegetative body of H. triceps to consist of a rhizome with a thickened root-cap-like structure that covered a vegetative shoot apical meristem. From the apical meristem, procambial strands originated and developed into endarch collateral vascular bundles arranged radially around a pith without an interfascicular cambium. Xylem vessels had scalariform pitting and simple …

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Sensory Genes And Mate Choice: Evidence That Duplications, Mutations, And Adaptive Evolution Alter Variation In Mating Cue Genes And Their Receptors, Lisa Horth Jan 2007

Sensory Genes And Mate Choice: Evidence That Duplications, Mutations, And Adaptive Evolution Alter Variation In Mating Cue Genes And Their Receptors, Lisa Horth

Biological Sciences Faculty Publications

Fascinating new data, revealed through gene sequencing, comparative genomics, and genetic engineering, precisely establish which genes are involved in mate choice and mating activity—behaviors that are surprisingly understudied from a genetic perspective. Discussed here are some of the recently identified visual and chemosensory genes that are involved in mate choice and mating behavior. These genes’ products are involved in the production, transmission, and receipt of crucial sensory mate-choice cues that affect fitness. This review exposes newfound evidence that alternative splicing, gene-expression pattern changes, and molecular genetic variation in sensory genes are crucial for both intra- and interspecific mate choice and …

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Bottom-Up Forcing And The Decline Of Steller Sea Lions (Eumetopias Jubatus) In Alaska: Assessing The Ocean Climate Hypothesis, Andrew W. Trites, Arthur J. Miller, Michael A. Alexander, Steven J. Bograd, John A. Calder, Antonietta Capotondi, Kenneth O. Coyle, Emanuele Di Lorenzo, Bruce P. Finney, Edward J. Gregr, Chester E. Grosch, Thomas C. Royer Jan 2007

Bottom-Up Forcing And The Decline Of Steller Sea Lions (Eumetopias Jubatus) In Alaska: Assessing The Ocean Climate Hypothesis, Andrew W. Trites, Arthur J. Miller, Michael A. Alexander, Steven J. Bograd, John A. Calder, Antonietta Capotondi, Kenneth O. Coyle, Emanuele Di Lorenzo, Bruce P. Finney, Edward J. Gregr, Chester E. Grosch, Thomas C. Royer

CCPO Publications

Declines of Steller sea lion ( Eumetopias jubatus) populations in the Aleutian Islands and Gulf of Alaska could be a consequence of physical oceanographic changes associated with the 1976–77 climate regime shift. Changes in ocean climate are hypothesized to have affected the quantity, quality, and accessibility of prey, which in turn may have affected the rates of birth and death of sea lions. Recent studies of the spatial and temporal variations in the ocean climate system of the North Pacific support this hypothesis. Ocean climate changes appear to have created adaptive opportunities for various species that are preyed upon …

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Self-Consistent Analyses For Potential Conduction Block In Nerves By An Ultrashort High-Intensity Electric Pulse, R. P. Joshi, A. Mishra, Q. Hu, K. H. Schoenbach, A. Pakhomov Jan 2007

Self-Consistent Analyses For Potential Conduction Block In Nerves By An Ultrashort High-Intensity Electric Pulse, R. P. Joshi, A. Mishra, Q. Hu, K. H. Schoenbach, A. Pakhomov

Bioelectrics Publications

Simulation studies are presented that probe the possibility of using high-field (>100kV ∕ cm), short-duration (∼50ns) electrical pulses for nonthermal and reversible cessation of biological electrical signaling pathways. This would have obvious applications in neurophysiology, clinical research, neuromuscular stimulation therapies, and even nonlethal bioweapons development. The concept is based on the creation of a sufficiently high density of pores on the nerve membrane by an electric pulse. This modulates membrane conductance and presents an effective "electrical short" to an incident voltage wave traveling across a nerve. Net blocking of action potential propagation can then result. A continuum approach based …

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Simulations Of Phytoplankton Species And Carbon Production In The Equatorial Pacific Ocean 1. Model Configuration And Ecosystem Dynamics, Baris Salihoglu, Eileen E. Hofmann Jan 2007

Simulations Of Phytoplankton Species And Carbon Production In The Equatorial Pacific Ocean 1. Model Configuration And Ecosystem Dynamics, Baris Salihoglu, Eileen E. Hofmann

OES Faculty Publications

The primary objective of this research is to investigate phytoplankton community response to variations in physical forcing and biological processes in the Cold Tongue region of the equatorial Pacific Ocean at 0N, 140W. This research objective was addressed using a one-dimensional multicomponent lower trophic level ecosystem model that includes detailed algal physiology, such as spectrally-dependent photosynthetic processes and iron limitation on algal growth. The ecosystem model is forced by a one-year (1992) time series of spectrally-dependent light, temperature, and water column mixing obtained from a Tropical Atmosphere-Ocean (TAO) Array mooring. Autotrophic growth is represented by five algal groups, which have …

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Otolith Chemistry Reflects Frontal Systems In The Antarctic Circumpolar Current, J. R. Ashford, A. I. Arkhipkin, C. M. Jones Jan 2007

Otolith Chemistry Reflects Frontal Systems In The Antarctic Circumpolar Current, J. R. Ashford, A. I. Arkhipkin, C. M. Jones

OES Faculty Publications

Pronounced environmental trends across fronts suggest that the otolith chemistry of oceanic fish can resolve zones on either side, promoting application to population questions at similar spatial scales. Trace and minor elements laid down immediately prior to capture - along the edges of otoliths from Patagonian toothfish Dissostichus eleginoides - discriminated frontal zones in the Antarctic Circumpolar Current in the Southwestern Atlantic Ocean. Mean values differentiated sampling areas by up to 2.6 standard deviations, suggesting: (1) otolith Mg/Ca enrichment related to fish activity around the Burdwood Bank; (2) Mn/Ca enrichment associated with South America; (3) Sr/Ca linked to the presence …

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