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2007

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The Effects Of Prior Knowledge Activation On Learner Retention Of New Concepts In Learning Objects, Kelsey Henderson Jan 2007

The Effects Of Prior Knowledge Activation On Learner Retention Of New Concepts In Learning Objects, Kelsey Henderson

Electronic Theses and Dissertations

Establishing relationships between a learner's prior knowledge and any new concepts he or she will be expected to learn is an important instructional activity. Learning objects are often devoid of such activities in an attempt to maintain their conciseness and reusability in a variety of instructional contexts. The purpose of this study was to examine the efficacy of using questioning as a prior knowledge activation strategy in learning objects. Previous research on the use prior knowledge activation strategies supports their effectiveness in helping to improve learner retention. Approaches such as questioning, advance organizers, and group discussions are examples of techniques …

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The Influence Of Discourse And Journal Writing On Second Graders' Acquisition Of Multidigit Addition Concepts, Elizabeth Hensley Jan 2007

The Influence Of Discourse And Journal Writing On Second Graders' Acquisition Of Multidigit Addition Concepts, Elizabeth Hensley

Electronic Theses and Dissertations

The purpose of this study was to examine how second graders use writing and language when they are learning to add multidigit numbers in mathematics class. Second grade students were taught addition conceptually with a focus on sharing their strategies and thought processes with each other during the mathematics lesson. Two social norms were established with students so that sharing information and asking for clarity when they did not understand would be natural and expected. Students kept a daily mathematics journal to answer the class's Problems of the Day. Patterns found in student journals indicated three stages of multidigit learning. …

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Sex-Biased Parasitism And The Reproductive Costs Of Parasites In A Social African Ground Squirrel, Melissa Ann Hillegass Jan 2007

Sex-Biased Parasitism And The Reproductive Costs Of Parasites In A Social African Ground Squirrel, Melissa Ann Hillegass

Electronic Theses and Dissertations

Vertebrate males frequently carry higher numbers of parasites than females. This bias in parasite loads could be a consequence of sexual selection. Grouping species are also assumed to be afflicted with larger numbers of parasites than solitary animals and associated costs of this parasitism could vary with group size or structure. I examined sex-biased parasitism and the influence of group size on parasite loads in Cape ground squirrels (Xerus inauris), a highly social species that occurs in the arid regions of southern Africa. Males carried three times as many ectoparasites as females, but females harbored nearly three times more endoparasites …

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Does Habitat Affect Clonal Demography? An Experiment With Polygonella Myriophylla In Roadside And Florida Scrub, Kristina Dianne Horn Jan 2007

Does Habitat Affect Clonal Demography? An Experiment With Polygonella Myriophylla In Roadside And Florida Scrub, Kristina Dianne Horn

Electronic Theses and Dissertations

Polygonella myriophylla (Polygonaceae) is a clonal shrub listed as endangered and narrowly endemic to pyrogenic scrub ecosystems in central Florida. It is almost restricted to gaps within the matrix of shrubs in the scrub but also occurs along adjacent road-side habitats. I hypothesize that persistent disturbed microhabitats and more dynamic sand accretion in roadsides will increase rooting probabilities compared to more stable scrub habitats, affecting survival, growth and reproduction. In April 2004- March 2006, I compared plant (genet) and basal branch (ramet) performance between experimentally manipulated plants in native scrub and roadside habitats at two locations within the Lake Wales …

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On Optimality Of Bayesian Testimation In The Normal Means Problem, Felix Abramovich, Vadim Grinshtein, Marianna Pensky Jan 2007

On Optimality Of Bayesian Testimation In The Normal Means Problem, Felix Abramovich, Vadim Grinshtein, Marianna Pensky

Faculty Bibliography 2000s

We consider a problem of recovering a high-dimensional vector mu observed in white noise, where the unknown vector g is assumed to be sparse. The objective of the paper is to develop a Bayesian formalism which gives rise to a family of l(0)-type penalties. The penalties are associated with various choices of the prior distributions pi(n)(center dot) on the number of nonzero entries of mu and, hence, are easy to interpret. The resulting Bayesian estimators lead to a general thresholding rule which accommodates many of the known thresholding and model selection procedures as particular cases corresponding to specific choices of …

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Peter Safar: Father Of Modern Cardiopulmonary Resuscitation, Louis J. Acierno, L. Timothy Worrell Jan 2007

Peter Safar: Father Of Modern Cardiopulmonary Resuscitation, Louis J. Acierno, L. Timothy Worrell

Faculty Bibliography 2000s

No abstract provided.

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Voigt Spectral Profiles In Two-Photon Resonance Fluorescence, Moorad Alexanian, Subir K. Bose Jan 2007

Voigt Spectral Profiles In Two-Photon Resonance Fluorescence, Moorad Alexanian, Subir K. Bose

Faculty Bibliography 2000s

A recent work on two-photon fluorescence is extended by considering the pump field to be a coherent state, which represents a laser field operating well above threshold. The dynamical conditions are investigated under which the two-photon spectrum gives rise, in addition to a Lorentzian line shape at the pump frequency, to two Voigt spectral sideband profiles. Additional conditions are found under which the Voigt profile behaves like either a Gaussian or a Lorentzian line shape.

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Toward A Formula-Based Model For Academic Library Funding: Statistical Significance And Implications Of A Model Based Upon Institutional Characteristics, Frank R. Allen, Mark Dickie Jan 2007

Toward A Formula-Based Model For Academic Library Funding: Statistical Significance And Implications Of A Model Based Upon Institutional Characteristics, Frank R. Allen, Mark Dickie

Faculty Bibliography 2000s

This study tests the hypothesis that a positive relationship exists between academic library funding (dependent variable) and selected institutional variables taken as indicators of the demand for library services at the university (enrollment, number of doctoral programs, doctoral degrees awarded, number of faculty, select other institutional characteristics). The research employs 11 years of longitudinal data from 113 members of the Association of Research Libraries to create a multiple regression model. Empirical results indicate that operational indicators of the demand for library services are positively associated with funding, and most of the associations are statistically significant at the five percent level …

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A Bayesian Approach To Estimation And Testing In Time-Course Microarray Experiments, Claudia Angelini, Daniela De Canditiis, Margherita Mutarelli, Marianna Pensky Jan 2007

A Bayesian Approach To Estimation And Testing In Time-Course Microarray Experiments, Claudia Angelini, Daniela De Canditiis, Margherita Mutarelli, Marianna Pensky

Faculty Bibliography 2000s

The objective of the present paper is to develop a truly functional Bayesian method specifically designed for time series microarray data. The method allows one to identify differentially expressed genes in a time-course microarray experiment, to rank them and to estimate their expression profiles. Each gene expression profile is modeled as an expansion over some orthonormal basis, where the coefficients and the number of basis functions are estimated from the data. The proposed procedure deals successfully with various technical difficulties that arise in typical microarray experiments such as a small number of observations, non-uniform sampling intervals and missing or replicated …

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Analysis Of Global Geomagnetic Variability, V. Anh, Z. -G. Yu, J. A. Wanliss Jan 2007

Analysis Of Global Geomagnetic Variability, V. Anh, Z. -G. Yu, J. A. Wanliss

Faculty Bibliography 2000s

The orthogonal field components from global INTERMAGNET magnetometer stations are studied via multifractal detrended fluctuation analysis to determine whether there are clear and consistent regional patterns in the behavior of the fluctuations. There are three distinct scaling regimes in the qth-order fluctuation function for each of the 24 stations studied covering Southwest North America, Northeast North America, Central Europe, Northern Europe, Australasia and Asia. There is a consistent break point at time scale around 23 h for all stations. The scaling exponents of the second-order fluctuation functions reflect the regional character of the stations, and can be used for station …

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Field Production And Functional Evaluation Of Chloroplast-Derived Interferon-Alpha 2b, Philip A. Arlen, Regina Falconer, Sri Cherukumili, Amy Cole, Alexander M. Cole, Karen K. Oishi, Henry Daniell Jan 2007

Field Production And Functional Evaluation Of Chloroplast-Derived Interferon-Alpha 2b, Philip A. Arlen, Regina Falconer, Sri Cherukumili, Amy Cole, Alexander M. Cole, Karen K. Oishi, Henry Daniell

Faculty Bibliography 2000s

Type I interferons (IFNs) inhibit viral replication and cell growth and enhance the immune response, and therefore have many clinical applications. IFN-alpha 2b ranks third in world market use for a biopharmaceutical, behind only insulin and erythropoietin. The average annual cost of IFN-alpha 2b for the treatment of hepatitis C infection is $26 000, and is therefore unavailable to the majority of patients in developing countries. Therefore, we expressed IFN-alpha 2b in tobacco chloroplasts, and transgenic lines were grown in the field after obtaining United States Department of Agriculture Animal and Plant Health Inspection Service (USDA-APHIS) approval. Stable, site-specific integration …

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Intravenous Immunoglobulin (Ivig) Protects The Brain Against Experimental Stroke By Preventing Complement-Mediated Neuronal Cell Death, Thiruma V. Arumugam, Sung-Chun Tang, Justin D. Lathia, Aiwu Cheng, Mohamed R. Mughal, Srinivasulu Chigurupati, Tim Magnus, Sic L. Chan, Dong-Gyu Jo, Xin Ouyang, David P. Fairlie, Daniel N. Granger, Alexander Vortmeyer, Milan Basta, Mark P. Mattson Jan 2007

Intravenous Immunoglobulin (Ivig) Protects The Brain Against Experimental Stroke By Preventing Complement-Mediated Neuronal Cell Death, Thiruma V. Arumugam, Sung-Chun Tang, Justin D. Lathia, Aiwu Cheng, Mohamed R. Mughal, Srinivasulu Chigurupati, Tim Magnus, Sic L. Chan, Dong-Gyu Jo, Xin Ouyang, David P. Fairlie, Daniel N. Granger, Alexander Vortmeyer, Milan Basta, Mark P. Mattson

Faculty Bibliography 2000s

Stroke is among the three leading causes of death worldwide and the most frequent cause of permanent disability. Brain ischemia induces an inflammatory response involving activated complement fragments. Here we show that i.v. Ig (IVIG) treatment, which scavenges complement fragments, protects brain cells against the deleterious effects of experimental ischemia and reperfusion (I/R) and prevents I/R-induced mortality in mice. Animals administered IVIG either 30 min before ischemia or after 3 h of reperfusion exhibited a 50-60% reduction of brain infarct size and a 2- to 3-fold improvement of the functional outcome. Even a single low dose of IVIG given after …

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Calculation Of Three-Body Resonances Using Slow-Variable Discretization Coupled With A Complex Absorbing Potential, Juan Blandon, Viatcheslav Kokoouline, Françoise Masnou-Seeuws Jan 2007

Calculation Of Three-Body Resonances Using Slow-Variable Discretization Coupled With A Complex Absorbing Potential, Juan Blandon, Viatcheslav Kokoouline, Françoise Masnou-Seeuws

Faculty Bibliography 2000s

We developed a method to calculate positions and widths of three-body resonances. The method combines the hyperspherical adiabatic approach, slow variable discretization method [O. I. Tolstikhin , J. Phys. B 29, L389 (1996)], and a complex absorbing potential. The method can be used to obtain resonances having short-range or long-range wave functions. In particular, we have applied the method to obtain very shallow three-body Efimov resonances for a model system [E. Nielsen , Phys. Rev. A 66, 012705 (2002)].

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Effect Of Packing Parameter On Phase Diagram Of Amphiphiles: An Off-Lattice Gibbs Ensemble Approach, Geuorgui K. Bourov, Aniket Bhattacharya Jan 2007

Effect Of Packing Parameter On Phase Diagram Of Amphiphiles: An Off-Lattice Gibbs Ensemble Approach, Geuorgui K. Bourov, Aniket Bhattacharya

Faculty Bibliography 2000s

We determine the phase diagram of several amphiphilic molecules as a function of the amphiphilic parameter alpha defined as the ratio of the volume of hydrophilic to hydrophobic segments using the Gibbs ensemble Monte Carlo method supplemented by configurational bias scheme. Specifically, we study amphiphilic molecules h(1)t(7), h(2)t(6), and h(3)t(5), for which alpha=0.14, 0.33, and 0.60 respectively, and demonstrate that the former two exhibit phase separation while h(3)t(5) forms micelles, supporting the contention that alpha=0.5 is the border line for phase separation and micellization, as observed in previous lattice Monte Carlo studies [Panagiotopoulos , Langmuir 18, 2940 (2002)]. Further, we …

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The Effects Of Year-Round Irrigation On Landscape Plant Quality And Health In Ohio, Heath Caldwell, Karen Mancl, Martin F. Quigley, Malcolm Pirnie Inc. Jan 2007

The Effects Of Year-Round Irrigation On Landscape Plant Quality And Health In Ohio, Heath Caldwell, Karen Mancl, Martin F. Quigley, Malcolm Pirnie Inc.

Faculty Bibliography 2000s

Deep (over 165 cm), permeable, unsaturated soil is needed to treat and dispose of wastewater through septic systems. In Ohio, only 6.4% of the state's land area is suited for septic systems for wastewater treatment. Soils with shallow depth to a limiting condition, between 30 and 60 cm, represent 49% of Ohio's land area. In these areas onsite wastewater treatment systems could be followed by irrigation on the lot to disperse the treated wastewater. Several months each year in Ohio reach subfreezing temperatures, making year-round irrigation a challenge. The objective of this research was to examine the feasibility of year-round …

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Nuclear Spectra Of Comet 28p Neujmin, Humberto Campins, Javier Licandro, Noemí Pinilla-Alonso, Kulie Ziffer, Julia De León, Thais Mothé-Diniz, Juan C. Guerra, Carl Hergenrother Jan 2007

Nuclear Spectra Of Comet 28p Neujmin, Humberto Campins, Javier Licandro, Noemí Pinilla-Alonso, Kulie Ziffer, Julia De León, Thais Mothé-Diniz, Juan C. Guerra, Carl Hergenrother

Faculty Bibliography 2000s

We present visible and near-infrared spectra of the nucleus of comet 28P/Neujmin 1, obtained in 2001, 2002, and 2003, while it had no detectable coma. The spectra show no strong features in this wavelength range, which prevented the identification of specific compounds on the surface of comet 28P. We found evidence for spectral variability, as our 2002 near-infrared spectrum has a significantly steeper slope than those obtained in 2001 and 2003. We compare the spectra of 28P with published spectra of other comet nuclei, with primitive asteroids and with meteorites. At near-infrared wavelengths, all the comet nuclei show spectra with …

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Self-Bending Of Dark And Gray Photorefractive Solitons, M. I. Carvalho, M. Facão, D. N. Christodoulides Jan 2007

Self-Bending Of Dark And Gray Photorefractive Solitons, M. I. Carvalho, M. Facão, D. N. Christodoulides

Faculty Bibliography 2000s

We investigate the effects of diffusion on the evolution of steady-state dark and gray spatial solitons in biased photorefractive media. Numerical integration of the nonlinear propagation equation shows that the soliton beams experience a modification of their initial trajectory, as well as a variation of their minimum intensity. This process is further studied using perturbation analysis, which predicts that the center of the optical beam moves along a parabolic trajectory and, moreover, that its minimum intensity varies linearly with the propagation distance, either increasing or decreasing depending on the sign of the initial transverse velocity. Relevant examples are provided.

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Electron Transport Through Single Carbon Nanotubes, G. Chai, H. Heinrich, L. Chow, T. Schenkel Jan 2007

Electron Transport Through Single Carbon Nanotubes, G. Chai, H. Heinrich, L. Chow, T. Schenkel

Faculty Bibliography 2000s

The authors report on the transport of energetic electrons through single, well aligned multiwall carbon nanotubes (CNTs). Embedding of CNTs in a protective carbon fiber coating enables the application of focused ion beam based sample preparation techniques for the nondestructive isolation and alignment of individual tubes. Aligned tubes with lengths of 0.7-3 mu m allow transport of 300 keV electrons in a transmission electron microscope through their hollow cores at zero degree incident angles and for a misalignment of up to 1 degrees.

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Decoupling Of Silicon Carbide Optical Sensor Response For Temperature And Pressure Measurements, A. Chakravarty, N. R. Quick, A. Kar Jan 2007

Decoupling Of Silicon Carbide Optical Sensor Response For Temperature And Pressure Measurements, A. Chakravarty, N. R. Quick, A. Kar

Faculty Bibliography 2000s

Single crystal silicon carbide is a chemically inert transparent material with superior oxidation-resistant properties at elevated temperatures compared to black polycrystalline silicon carbide substrates. These improved properties make crystalline silicon carbide a good optical sensor material for harsh environments such as combustion chambers and turbine systems. Interferometric optical sensors are orders of magnitude more sensitive than electrical sensors and are proposed for these applications. Silicon carbide itself behaves as a Fabry-Perot etalon eliminating the need for an external interferometer for any measurement using this silicon carbide as a sensor. The principle of the optical sensor in this study is the …

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Editorial: Remote Sensing For Environmental Studies, Ni-Bin Chang Jan 2007

Editorial: Remote Sensing For Environmental Studies, Ni-Bin Chang

Faculty Bibliography 2000s

No abstract provided.

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Stable Expression Of Gal/Galnac Lectin Of Entamoeba Histolytica In Transgenic Chloroplasts And Immunogenicity In Mice Towards Vaccine Development For Amoebiasis, Seethamahalakshmi Chebolu, Henry Daniell Jan 2007

Stable Expression Of Gal/Galnac Lectin Of Entamoeba Histolytica In Transgenic Chloroplasts And Immunogenicity In Mice Towards Vaccine Development For Amoebiasis, Seethamahalakshmi Chebolu, Henry Daniell

Faculty Bibliography 2000s

Chloroplast genetic engineering offers several advantages, including high levels of transgene expression, transgene containment via maternal inheritance and multigene engineering in a single transformation event. Entamoeba histolytica infects 50 million people, causing about 100 000 deaths annually, but there is no approved vaccine against this pathogen. LecA, a potential target for blocking amoebiasis, was expressed for the first time in transgenic plants. Stable transgene integration into chloroplast genomes and homoplasmy were confirmed by polymerase chain reaction and Southern blot analyses. LecA expression was evaluated by Western blots and quantified by enzyme-linked immunosorbent assay (up to 6.3% of total soluble protein …

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Prostasin Induces Protease-Dependent And Independent Molecular Changes In The Human Prostate Carcinoma Cell Line Pc-3, Mengqian Chen, Ya-Yuan Fu, Chen-Yong Lin, Li-Mei Chen, Karl X. Chai Jan 2007

Prostasin Induces Protease-Dependent And Independent Molecular Changes In The Human Prostate Carcinoma Cell Line Pc-3, Mengqian Chen, Ya-Yuan Fu, Chen-Yong Lin, Li-Mei Chen, Karl X. Chai

Faculty Bibliography 2000s

Expression of prostasin in the PC-3 human prostate carcinoma cells inhibited in vitro invasion, but the molecular mechanisms are unknown. Wild-type human prostasin or a serine active-site mutant prostasin was expressed in the PC-3 cells. Molecular changes were measured at the mRNA and the protein levels. Cell signaling changes were evaluated by measuring phosphorylation of the extracellular signal-regulated kinases (Erk 1/2) following epidermal growth factor (EGF) treatment of the cells. Protein expression of the EGF receptor (EGFR) was differentially downregulated by the wild-type and the active-site mutant prostasin. The mRNA expression of EGFR and the transcription repressor SLUG was reduced …

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Sharp Estimates On Minimum Travelling Wave Speed Of Reaction Diffusion Systems Modelling Autocatalysis, Xinfu Chen, Yuanwei Qi Jan 2007

Sharp Estimates On Minimum Travelling Wave Speed Of Reaction Diffusion Systems Modelling Autocatalysis, Xinfu Chen, Yuanwei Qi

Faculty Bibliography 2000s

This article studies propagating wave fronts in an isothermal chemical reaction A + 2B - > 3B involving two chemical species, a reactant A and an autocatalyst B, whose diffusion coefficients, D-A and D-B, are unequal due to different molecular weights and/or sizes. Explicit bounds v(*) and v* that depend on D-B/D-A are derived such that there is a unique travelling wave of every speed v > = v* and there does not exist any travelling wave of speed v < v*. New to the literature, it is shown that v(*) proportional to v* proportional to D-B/D-A when D-B = v(min). Estimates on v(min) significantly improve those of early works. The framework is built upon general isothermal autocatalytic chemical reactions A + nB - > (n + 1)B of arbitrary order n > = 1.

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Radiation Properties In Electron Waveguides, Yupeng Chen, Thomas X. Wu Jan 2007

Radiation Properties In Electron Waveguides, Yupeng Chen, Thomas X. Wu

Faculty Bibliography 2000s

We study the radiation properties in electron waveguide structure with multistep discontinuities and soft wall lateral confinement. Radiation mechanism and conditions are examined by numerical simulation of dispersion relations and transport properties. The study of geometry variations shows its significant impact on the radiation intensity and direction. In particular, the periodic corrugation structure exhibits strong directional radiation. This interesting feature may be useful to design a nanoscale transmitter, a communication device for future nanoscale system.

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Domac: An Accurate, Hybrid Protein Domain Prediction Server, Jianlin Cheng Jan 2007

Domac: An Accurate, Hybrid Protein Domain Prediction Server, Jianlin Cheng

Faculty Bibliography 2000s

Protein domain prediction is important for protein structure prediction, structure determination, function annotation, mutagenesis analysis and protein engineering. Here we describe an accurate protein domain prediction server (DOMAC) combining both template-based and ab initio methods. The preliminary version of the server was ranked among the top domain prediction servers in the seventh edition of Critical Assessment of Techniques for Protein Structure Prediction (CASP7), 2006. DOMAC server and datasets are available at: http://www.bioinfotool.org/domac.html.

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Improved Residue Contact Prediction Using Support Vector Machines And A Large Feature Set, Jianlin Cheng, Pierre Baldi Jan 2007

Improved Residue Contact Prediction Using Support Vector Machines And A Large Feature Set, Jianlin Cheng, Pierre Baldi

Faculty Bibliography 2000s

Background: Predicting protein residue-residue contacts is an important 2D prediction task. It is useful for ab initio structure prediction and understanding protein folding. In spite of steady progress over the past decade, contact prediction remains still largely unsolved. Results: Here we develop a new contact map predictor (SVMcon) that uses support vector machines to predict medium- and long-range contacts. SVMcon integrates profiles, secondary structure, relative solvent accessibility, contact potentials, and other useful features. On the same test data set, SVMcon's accuracy is 4% higher than the latest version of the CMAPpro contact map predictor. SVMcon recently participated in the seventh …

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Effect Of The Concentration Of Organic Dyes On Their Surface Plasmon Enhanced Two-Photon Absorption Cross Section Using Activated Au Nanoparticles, Ion Cohanoschi, Sheng Yao, Kevin D. Belfield, Florencio E. Hernández Jan 2007

Effect Of The Concentration Of Organic Dyes On Their Surface Plasmon Enhanced Two-Photon Absorption Cross Section Using Activated Au Nanoparticles, Ion Cohanoschi, Sheng Yao, Kevin D. Belfield, Florencio E. Hernández

Faculty Bibliography 2000s

In this article we present the study of the surface plasmon enhanced two-photon absorption of a hydrophilic stilbene derivative (trans-4,4'-diaminostilbene) in aqueous solution at different concentrations. The observed exponential growth of the effective two-photon absorption cross section [sigma(')(2)(Au)] is attributed to the electric-field augmentation via surface plasmon resonance between nanoparticles, i.e., hot spots, and the molecular density on Au nanospheres. An unprecedented sigma(')(2)(Au)=550 000 GM has been measured. This result opens a new universe of applications in multiphoton imaging, photodynamic therapy, telecommunications, optical limiting, and multidimensional data storage using hybrid systems.

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Lunar Surface: Dust Dynamics And Regolith Mechanics, J. E. Colwell, S. Batiste, M. Horányi, S. Robertson, S. Sture Jan 2007

Lunar Surface: Dust Dynamics And Regolith Mechanics, J. E. Colwell, S. Batiste, M. Horányi, S. Robertson, S. Sture

Faculty Bibliography 2000s

The lunar surface is characterized by a collisionally evolved regolith resulting from meteoroid bombardment. This lunar soil consists of highly angular particles in a broad, approximately power law size distribution, with impact-generated glasses. The regolith becomes densified and difficult to excavate when subjected to lunar quakes or, eventually, manned and unmanned activity on the surface. Solar radiation and the solar wind produce a plasma sheath near the lunar surface. Lunar grains acquire charge in this environment and can exhibit unusual behavior, including levitation and transport across the surface because of electric fields in the plasma sheath. The fine component of …

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Elevated Soil Lead: Statistical Modeling And Apportionment Of Contributions From Lead-Based Paint And Leaded Gasoline, R. Dennis Cook, Liqiang Ni Jan 2007

Elevated Soil Lead: Statistical Modeling And Apportionment Of Contributions From Lead-Based Paint And Leaded Gasoline, R. Dennis Cook, Liqiang Ni

Faculty Bibliography 2000s

While it is widely accepted that lead-based paint and leaded gasoline are primary sources of elevated concentrations of lead in residential soils, conclusions regarding their relative contributions are mixed and generally study specific. We develop a novel nonlinear regression for soil lead concentrations over time. It is argued that this methodology provides useful insights into the partitioning of the average soil lead concentration by source and time over large residential areas. The methodology is Used to investigate soil lead concentrations from the 1987 Minnesota Lead Study and the 1990 National Lead Survey. Potential litigation issues are disscussed briefly.

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Design And Construction Of An Electric Fish Finder, William G. R. Crampton, Jonathan K. Wells, Charles Smuth, Steven A. Walz Jan 2007

Design And Construction Of An Electric Fish Finder, William G. R. Crampton, Jonathan K. Wells, Charles Smuth, Steven A. Walz

Faculty Bibliography 2000s

We provide notes on the design and construction of an Electric Fish Finder - a portable differential amplifier for detecting the electrostatic fields of gymnotiform knifefishes. The device can be adapted to locate electric fishes in any kind of aquatic environment. It is rugged, water resistant, and powered by alkaline batteries. This contribution is part of a series of technical papers designed to encourage students of neotropical ichthyology to explore the ecology, systematics, and electric signaling of gymnotiform fishes.

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