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University of Central Florida

Faculty Bibliography 2000s

2009

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Habitat-Specific Breeder Survival Of Florida Scrub-Jays: Inferences From Multistate Models, David R. Breininger, James D. Nichols, Geoffrey M. Carter, Donna M. Oddy Jan 2009

Habitat-Specific Breeder Survival Of Florida Scrub-Jays: Inferences From Multistate Models, David R. Breininger, James D. Nichols, Geoffrey M. Carter, Donna M. Oddy

Faculty Bibliography 2000s

Quantifying habitat-specific survival and changes in habitat quality within disturbance-prone habitats is critical for understanding population dynamics and variation in fitness, and for managing degraded ecosystems. We used 18 years of color-banding data and multistate capture-recapture models to test whether habitat quality within territories influences survival and detection probability of breeding Florida Scrub-Jays (Aphelocoma coerulescens) and to estimate bird transition probabilities from one territory quality state to another. Our study sites were along central Florida's Atlantic coast and included two of the four largest metapopulations within the species range. We developed Markov models for habitat transitions and compared these to …

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The Longin Domain Regulates The Steady-State Dynamics Of Sec22 In Plasmodium Falciparum, Lawrence Ayong, Avanthi Raghavan, Timothy G. Schneider, Theodore F. Taraschi, David A. Fidock, Debopam Chakrabarti Jan 2009

The Longin Domain Regulates The Steady-State Dynamics Of Sec22 In Plasmodium Falciparum, Lawrence Ayong, Avanthi Raghavan, Timothy G. Schneider, Theodore F. Taraschi, David A. Fidock, Debopam Chakrabarti

Faculty Bibliography 2000s

The specificity of vesicle-mediated transport is largely regulated by the membrane-specific distribution of SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins. However, the signals and machineries involved in SNARE protein targeting to the respective intracellular locations are not fully understood. We have identified a Sec22 ortholog in Plasmodium falciparum (PfSec22) that contains an atypical insertion of the Plasmodium export element within the N-terminal longin domain. This Sec22 protein partially associates with membrane structures in the parasitized erythrocytes when expressed under the control of the endogenous promoter element. Our studies indicate that the atypical longin domain contains signals that are required …

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Beat The Diffraction Limit In 3d Direct Laser Writing In Photosensitive Glass, Matthieu Bellec, Arnaud Royon, Bruno Bousquet, Kevin Bourhis, Mona Treguer, Thierry Cardinal, Martin Richardson, Lionel Canioni Jan 2009

Beat The Diffraction Limit In 3d Direct Laser Writing In Photosensitive Glass, Matthieu Bellec, Arnaud Royon, Bruno Bousquet, Kevin Bourhis, Mona Treguer, Thierry Cardinal, Martin Richardson, Lionel Canioni

Faculty Bibliography 2000s

Three-dimensional (3D) femtosecond laser direct structuring in transparent materials is widely used for photonic applications. However, the structure size is limited by the optical diffraction. Here we report on a direct laser writing technique that produces subwavelength nanostructures independently of the experimental limiting factors. We demonstrate 3D nanostructures of arbitrary patterns with feature sizes down to 80 nm, less than one tenth of the laser processing wavelength. Its ease of implementation for novel nanostructuring, with its accompanying high precision will open new opportunities for the fabrication of nanostructures for plasmonic and photonic devices and for applications in metamaterials.

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Periodic Radio And H Alpha Emission From The L Dwarf Binary 2massw J0746425 + 200032: Exploring The Magnetic Field Topology And Radius Of An L Dwarf, E. Berger, R. E. Rutledge, N. Phan-Bao, G. Basri, M. S. Giampapa, J. E. Gizis, J. Liebert, E. Martín, T. A. Fleming Jan 2009

Periodic Radio And H Alpha Emission From The L Dwarf Binary 2massw J0746425 + 200032: Exploring The Magnetic Field Topology And Radius Of An L Dwarf, E. Berger, R. E. Rutledge, N. Phan-Bao, G. Basri, M. S. Giampapa, J. E. Gizis, J. Liebert, E. Martín, T. A. Fleming

Faculty Bibliography 2000s

We present an 8.5 hr simultaneous radio, X-ray, UV, and optical observation of the L dwarf binary 2MASSW J0746425+200032. We detect strong radio emission, dominated by short-duration periodic pulses at 4.86 GHz with P = 124.32 +/- 0.11 min. The stability of the pulse profiles and arrival times demonstrates that they are due to the rotational modulation of a B approximate to 1.7 kG magnetic field. A quiescent nonvariable component is also detected, likely due to emission from a uniform large-scale field. The Ha emission exhibits identical periodicity, but unlike the radio pulses it varies sinusoidally and is offset by …

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Neighbourhood Friends, Vanessa M. Blakeslee Jan 2009

Neighbourhood Friends, Vanessa M. Blakeslee

Faculty Bibliography 2000s

No abstract provided.

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Extreme Value Statistics In Silicon Photonics, D. Borlaug, S. Fathpour, B. Jalali Jan 2009

Extreme Value Statistics In Silicon Photonics, D. Borlaug, S. Fathpour, B. Jalali

Faculty Bibliography 2000s

L-shape probability distributions are extremely non-Gaussian functions that have been surprisingly successful in describing the occurrence of extreme events ranging from stock market crashes, natural disasters, structure of biological systems, fractals, and optical rogue waves. We show that fluctuations in stimulated Raman scattering, as well as in coherent anti-Stokes Raman scattering, in silicon can follow extreme value statistics and provide mathematical insight into the origin of this behavior.

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Water In Comets 71p/Clark And C/2004 B1 (Linear) With Spitzer, Dominique Bockelée-Morvan, Charles E. Woodward, Michael S. Kelley, Diane H. Wooden Jan 2009

Water In Comets 71p/Clark And C/2004 B1 (Linear) With Spitzer, Dominique Bockelée-Morvan, Charles E. Woodward, Michael S. Kelley, Diane H. Wooden

Faculty Bibliography 2000s

We present 5.5-7.6 mu m spectra of comets 71P/Clark (2006 May 27.56 UT, r(h) = 1.57 AU pre-perihelion) and C/2004 B1 (LINEAR) (2005 October 15.22 UT, r(h) = 2.21 AU pre-perihelion and 2006 May 16.22 UT, r(h) = 2.06 AU post-perihelion) obtained with the Spitzer Space Telescope. The nu(2) vibrational band of water is detected with a signal-to-noise ratio of 11-50. Fitting the spectra using a fluorescence model of water emission yields a water rotational temperature of < 18 K for 71P/Clark and similar or equal to 14 +/- 2K (pre-perihelion) and 23 +/- 4K (post-perihelion) for C/2004 B1 (LINEAR). The water ortho-to-para ratio in C/2004 B1 (LINEAR) is measured to be 2.31 +/- 0.18, which corresponds to a spin temperature of 26(-2)(+3) K. Water production rates are derived. The agreement between the water model and the measurements is good, as previously found for Spitzer spectra of C/2003 K4 (LINEAR). The Spitzer spectra of these three comets do not show any evidence for emission from polycyclic aromatic hydrocarbons and carbonate minerals, in contrast to results reported for comets 9P/Tempel 1 and C/1995 O1 (Hale-Bopp).

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A New Measurement Of Sequence Conservation, Xiaohui Cai, Haiyan Hu, Xiaoman Li Jan 2009

A New Measurement Of Sequence Conservation, Xiaohui Cai, Haiyan Hu, Xiaoman Li

Faculty Bibliography 2000s

Background: Understanding sequence conservation is important for the study of sequence evolution and for the identification of functional regions of the genome. Current studies often measure sequence conservation based on every position in contiguous regions. Therefore, a large number of functional regions that contain conserved segments separated by relatively long divergent segments are ignored. Our goal in this paper is to define a new measurement of sequence conservation such that both contiguously conserved regions and discontiguously conserved regions can be detected based on this new measurement. Here and in the following, conserved regions are those regions that share similarity higher …

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Evidence For An Ancient Adaptive Episode Of Convergent Molecular Evolution, Todd A. Castoe, A. P. Jason De Koning, Hyun-Min Kim, Wanjun Gu, Brice P. Noonan, Gavin Naylor, Zhi J. Jiang, Christopher L. Parkinson, David D. Pollock Jan 2009

Evidence For An Ancient Adaptive Episode Of Convergent Molecular Evolution, Todd A. Castoe, A. P. Jason De Koning, Hyun-Min Kim, Wanjun Gu, Brice P. Noonan, Gavin Naylor, Zhi J. Jiang, Christopher L. Parkinson, David D. Pollock

Faculty Bibliography 2000s

Documented cases of convergent molecular evolution due to selection are fairly unusual, and examples to date have involved only a few amino acid positions. However, because convergence mimics shared ancestry and is not accommodated by current phylogenetic methods, it can strongly mislead phylogenetic inference when it does occur. Here, we present a case of extensive convergent molecular evolution between snake and agamid lizard mitochondrial genomes that overcomes an otherwise strong phylogenetic signal. Evidence from morphology, nuclear genes, and most sites in the mitochondrial genome support one phylogenetic tree, but a subset of mostly amino acid-altering substitutions ( primarily at the …

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Comparative Data Mining Analysis For Information Retrieval Of Modis Images: Monitoring Lake Turbidity Changes At Lake Okeechobee, Florida, Ni-Bin Chang, Ammarin Daranpob, Y. Jeffrey Yang, Kang-Ren Jin Jan 2009

Comparative Data Mining Analysis For Information Retrieval Of Modis Images: Monitoring Lake Turbidity Changes At Lake Okeechobee, Florida, Ni-Bin Chang, Ammarin Daranpob, Y. Jeffrey Yang, Kang-Ren Jin

Faculty Bibliography 2000s

In the remote sensing field, a frequently recurring question is: Which computational intelligence or data mining algorithms are most suitable for the retrieval of essential information given that most natural systems exhibit very high non-linearity. Among potential candidates might be empirical regression, neural network model, support vector machine, genetic algorithm/genetic programming, analytical equation, etc. This paper compares three types of data mining techniques, including multiple non-linear regression, artificial neural networks, and genetic programming, for estimating multi-temporal turbidity changes following hurricane events at Lake Okeechobee, Florida. This retrospective analysis aims to identify how the major hurricanes impacted the water quality management …

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Urban Land Use And Land Cover Classification Using The Neural-Fuzzy Inference Approach With Formosat-2 Data, Ho-Wen Chen, Ni-Bin Chang, Ruey-Fang Yu, Yi-Wen Huang Jan 2009

Urban Land Use And Land Cover Classification Using The Neural-Fuzzy Inference Approach With Formosat-2 Data, Ho-Wen Chen, Ni-Bin Chang, Ruey-Fang Yu, Yi-Wen Huang

Faculty Bibliography 2000s

This paper presents a neural-fuzzy inference approach to identify the land use and land cover (LULC) patterns in a fast growing urban region with the 8-meter resolution of multi-spectral images collected by Formosat-2 satellite. Texture and feature analyses support the retrieval of fuzzy rules in the context of data mining to discern the embedded LULC patterns via a neural-fuzzy inference approach. The case study for Taichung City in central Taiwan shows the application potential based on five LULC classes. With the aid of integrated fuzzy rules and a neural network model, the optimal weights associated with these achievable rules can …

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Loss Of Prostasin (Prss8) In Human Bladder Transitional Cell Carcinoma Cell Lines Is Associated With Epithelial-Mesenchymal Transition (Emt), Li-Mei Chen, Nicole J. Verity, Karl X. Chai Jan 2009

Loss Of Prostasin (Prss8) In Human Bladder Transitional Cell Carcinoma Cell Lines Is Associated With Epithelial-Mesenchymal Transition (Emt), Li-Mei Chen, Nicole J. Verity, Karl X. Chai

Faculty Bibliography 2000s

Background: The glycosylphosphatidylinositol (GPI)-anchored epithelial extracellular membrane serine protease prostasin (PRSS8) is expressed abundantly in normal epithelia and essential for terminal epithelial differentiation, but down-regulated in human prostate, breast, and gastric cancers and invasive cancer cell lines. Prostasin is involved in the extracellular proteolytic modulation of the epidermal growth factor receptor (EGFR) and is an invasion suppressor. The aim of this study was to evaluate prostasin expression states in the transitional cell carcinomas (TCC) of the human bladder and in human TCC cell lines. Methods: Normal human bladder tissues and TCC on a bladder cancer tissue microarray (TMA) were evaluated …

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The Homocysteine-Inducible Endoplasmic Reticulum Stress Protein Counteracts Calcium Store Depletion And Induction Of Ccaat Enhancer-Binding Protein Homologous Protein In A Neurotoxin Model Of Parkinson Disease, Srinivasulu Chigurupati, Zelan Wei, Cherine Belal, Myrian Vandermey, George A. Kyriazis, Thiruma V. Arumugam, Sic L. Chan Jan 2009

The Homocysteine-Inducible Endoplasmic Reticulum Stress Protein Counteracts Calcium Store Depletion And Induction Of Ccaat Enhancer-Binding Protein Homologous Protein In A Neurotoxin Model Of Parkinson Disease, Srinivasulu Chigurupati, Zelan Wei, Cherine Belal, Myrian Vandermey, George A. Kyriazis, Thiruma V. Arumugam, Sic L. Chan

Faculty Bibliography 2000s

The endoplasmic reticulum (ER) is a key organelle regulating intracellular Ca(2+) homeostasis. Oxidants and mitochondria-derived free radicals can target ER-based Ca(2+) regulatory proteins and cause uncontrolled Ca(2+) release that may contribute to protracted ER stress and apoptosis. Several ER stress proteins have been suggested to counteract the deregulation of ER Ca(2+) homeostasis and ER stress. Here we showed that knockdown of Herp, an ubiquitin-like domain containing ER stress protein, renders PC12 and MN9D cells vulnerable to 1-methyl-4-phenylpyridinium-induced cytotoxic cell death by a mechanism involving up-regulation of CHOP expression and ER Ca(2+) depletion. Conversely, Herp overexpression confers protection by blocking 1-methyl-4-phenylpyridinium-induced …

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Self-Assembly Of Densely Packed And Aligned Bilayer Zno Nanorod Arrays, L. Chow, O. Lupan, H. Heinrich, G. Chai Jan 2009

Self-Assembly Of Densely Packed And Aligned Bilayer Zno Nanorod Arrays, L. Chow, O. Lupan, H. Heinrich, G. Chai

Faculty Bibliography 2000s

We present a method of self-assembly of densely packed and aligned bilayer ZnO nanorod arrays in a hydrothermal synthesis process. The alkali hydrothermal environment first induced the growth of hydrotalcitelike zincowoodwardite plates, which provide a lattice-matched surface for the self-assembly of ZnO nanorod arrays. The high packing density of the ZnO nanorod arrays demonstrates efficient nucleation and growth processes of ZnO on the zincowoodwardite. The interfacial phenomena involved in the growth of ZnO and self-assembly are discussed. The two-dimensional arrays of ZnO nanorods may find future applications in nanoelectronics and nanophotonics.

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Analysis And Design Of Wide-Angle Foveated Optical Systems Based On Transmissive Liquid Crystal Spatial Light Modulators, George Curatu, James E. Harvey Jan 2009

Analysis And Design Of Wide-Angle Foveated Optical Systems Based On Transmissive Liquid Crystal Spatial Light Modulators, George Curatu, James E. Harvey

Faculty Bibliography 2000s

Optical foveated imaging using liquid crystal (LC) spatial light modulators (SLMs) has received considerable attention in recent years as a potential approach to reducing size and complexity in fast wideangle lenses. We cover a theoretical study quantifying the diffraction efficiency and image quality of foveated optical systems (FOSs) based on transmissive LC SLMs. A practical design example of a fast wideangle FOS based on the current transmissive LC SLM technology is proposed.

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Optimization Of Codon Composition And Regulatory Elements For Expression Of Human Insulin Like Growth Factor-1 In Transgenic Chloroplasts And Evaluation Of Structural Identity And Function, Henry Daniell, Gricel Ruiz, Bela Denes, Laurence Sandberg, William Langridge Jan 2009

Optimization Of Codon Composition And Regulatory Elements For Expression Of Human Insulin Like Growth Factor-1 In Transgenic Chloroplasts And Evaluation Of Structural Identity And Function, Henry Daniell, Gricel Ruiz, Bela Denes, Laurence Sandberg, William Langridge

Faculty Bibliography 2000s

Background: Transgenic chloroplasts are potential bioreactors for recombinant protein production, especially for achievement of high levels of protein expression and proper folding. Production of therapeutic proteins in leaves provides transgene containment by elimination of reproductive structures. Therefore, in this study, human Insulin like Growth Factor-1 is expressed in transgenic chloroplasts for evaluation of structural identity and function. Results: Expression of the synthetic Insulin like Growth Factor 1 gene (IGF-1s, 60% AT) was observed in transformed E. coli. However, no native IGF-1 gene (IGF-1n, 41% AT) product was detected in the western blots in E. coli. Site-specific integration of the transgenes …

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A Novel In Vitro Multiple-Stress Dormancy Model For Mycobacterium Tuberculosis Generates A Lipid-Loaded, Drug-Tolerant, Dormant Pathogen, Chirajyoti Deb, Chang-Muk Lee, Vinod S. Dubey, Jaiyanth Daniel, Bassam Abomoelak, Tatiana D. Sirakova, Santosh Pawar, Linda Rogers, Pappachan E. Kolattukudy Jan 2009

A Novel In Vitro Multiple-Stress Dormancy Model For Mycobacterium Tuberculosis Generates A Lipid-Loaded, Drug-Tolerant, Dormant Pathogen, Chirajyoti Deb, Chang-Muk Lee, Vinod S. Dubey, Jaiyanth Daniel, Bassam Abomoelak, Tatiana D. Sirakova, Santosh Pawar, Linda Rogers, Pappachan E. Kolattukudy

Faculty Bibliography 2000s

Background: Mycobacterium tuberculosis (Mtb) becomes dormant and phenotypically drug resistant when it encounters multiple stresses within the host. Inability of currently available drugs to kill latent Mtb is a major impediment to curing and possibly eradicating tuberculosis (TB). Most in vitro dormancy models, using single stress factors, fail to generate a truly dormant Mtb population. An in vitro model that generates truly dormant Mtb cells is needed to elucidate the metabolic requirements that allow Mtb to successfully go through dormancy, identify new drug targets, and to screen drug candidates to discover novel drugs that can kill dormant pathogen. Methodology/Principal Findings: …

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Two-Photon Photodetector In A Multiquantum Well Gaas Laser Structure At 1.55 Mu M, D. Duchesne, L. Razzari, L. Halloran, R. Morandotti, A. J. Spring Thorpe, D. N. Christodoulides, D. J. Moss Jan 2009

Two-Photon Photodetector In A Multiquantum Well Gaas Laser Structure At 1.55 Mu M, D. Duchesne, L. Razzari, L. Halloran, R. Morandotti, A. J. Spring Thorpe, D. N. Christodoulides, D. J. Moss

Faculty Bibliography 2000s

We report two-photon photocurrent in a GaAs/AlGaAs multiple quantum well laser at 1.55 mu m. Using 1ps pulses, a purely quadratic photocurrent is observed. We measure the device efficiency, sensitivity, as well as the two-photon absorption coefficient. The results show that the device has potential for signal processing, autocorrelation and possibly two-photon source applications at sub-Watt power levels.

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Nonlinear Optical Dynamics In Nonideal Gases Of Interacting Colloidal Nanoparticles, R. El-Ganainy, D. N. Christodoulides, E. M. Wright, W. M. Lee, K. Dholakia Jan 2009

Nonlinear Optical Dynamics In Nonideal Gases Of Interacting Colloidal Nanoparticles, R. El-Ganainy, D. N. Christodoulides, E. M. Wright, W. M. Lee, K. Dholakia

Faculty Bibliography 2000s

We show that many-body effects in stabilized nanocolloidal suspensions can have a profound effect on their optical nonlinearity. By considering the screened Coulomb repulsions between nanoparticles, we find that the nonlinear optical behavior of these colloids can range from polynomial to exponential depending on their composition and chemistry. The dynamics and stability properties of optical beams propagating in such nonideal gas environments of interacting colloidal particles are investigated. Our analysis provides a theoretical foundation for understanding the recently observed super-Kerr nonlinear optical response of such systems.

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Albedos Of Small Jovian Trojans, Yanga R. Fernández, David Jewitt, Julie E. Ziffer Jan 2009

Albedos Of Small Jovian Trojans, Yanga R. Fernández, David Jewitt, Julie E. Ziffer

Faculty Bibliography 2000s

We present thermal observations of 44 Jovian Trojan asteroids with diameters D ranging from 5 to 24 km. All objects were observed at a wavelength of 24 mu m with the Spitzer Space Telescope. Measurements of the thermal emission and of scattered optical light, mostly from the University of Hawaii 2.2 m Telescope, together allow us to constrain the diameter and geometric albedo of each body. We find that the median R-band albedo of these small Jovian Trojans is about 0.12, much higher than that of "large" Trojans with D > 57 km (0.04). Also the range of albedos among the …

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Social Service Staffing In Us Nursing Homes, Denise Gammonley, Ning Jackie Zhang, Kathryn Frahm, Seung Chun Paek Jan 2009

Social Service Staffing In Us Nursing Homes, Denise Gammonley, Ning Jackie Zhang, Kathryn Frahm, Seung Chun Paek

Faculty Bibliography 2000s

Using data from the 2003 national Online Survey Certification and Reporting System, this study examines how the structure of social service staffing in nursing homes is affected by organizational and contextual factors. The results suggest that, although federal regulations impose minimal obligation, requiring only facilities with more than 120 beds to employ qualified social service providers, nearly 12 percent of these facilities failed to meet this staffing requirement in 2003. Results further suggest that the skill mix of social service providers in nursing homes is influenced by market competition, market demand, facility ownership, aggregate resident acuity, and the proportion of …

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Met Receptor Tyrosine Kinase Degradation Is Altered In Response To The Leucine-Rich Repeat Of The Listeria Invasion Protein Internalin B, Xiu Gao, Marta Lorinczi, Kristen S. Hill, Natasha C. Brooks, Hatem Dokainish, Keith Ireton, Lisa A. Elferink Jan 2009

Met Receptor Tyrosine Kinase Degradation Is Altered In Response To The Leucine-Rich Repeat Of The Listeria Invasion Protein Internalin B, Xiu Gao, Marta Lorinczi, Kristen S. Hill, Natasha C. Brooks, Hatem Dokainish, Keith Ireton, Lisa A. Elferink

Faculty Bibliography 2000s

Entry of the bacterial pathogen Listeria monocytogenes into host epithelial cells is critical for infection and virulence. One major pathway for Listeria entry involves binding of the bacterial protein Internalin B to the host receptor tyrosine kinase Met ( hepatocyte growth factor receptor). Activation of Met and downstream signaling cascades is critical for Listeria entry. Internalin B is composed of several structural domains including an N-terminal leucine-rich repeat that is sufficient for binding Met and stimulating downstream signal transduction. Internalin B is monomeric, whereas the leucine-rich repeat is dimeric when expressed as an isolated fragment. The different quaternary states of …

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Modeling The Land Surface Heat Exchange Process With The Aid Of Moderate Resolution Imaging Spectroradiometer Images, Zhiqiang Gao, Wenjiang Zhang, Wei Gao, Ni-Bin Chang Jan 2009

Modeling The Land Surface Heat Exchange Process With The Aid Of Moderate Resolution Imaging Spectroradiometer Images, Zhiqiang Gao, Wenjiang Zhang, Wei Gao, Ni-Bin Chang

Faculty Bibliography 2000s

Most ecosystems and crops experience water stress in arid and semiarid areas of the Inner Mongolia grassland, Northern China. Yet the lack of long-term in situ monitoring data hinders the managerial capacity of changing water vapor environment, which is tied with sustaining the grassland in the Inner Mongolia. Environmental remote sensing monitoring and modeling may provide synergistic means of observing changes in thermodynamic balance during drought onset at the grassland surface, providing reliable projections accounting for variations and correlations of water vapor and heat fluxes. It is the aim of this paper to present a series of estimates of latent …

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Experimental Observation Of Mode-Selective Anticrossing In Surface-Plasmon-Coupled Metal Nanoparticle Arrays, Amitabh Ghoshal, Ivan Divliansky, Pieter G. Kik Jan 2009

Experimental Observation Of Mode-Selective Anticrossing In Surface-Plasmon-Coupled Metal Nanoparticle Arrays, Amitabh Ghoshal, Ivan Divliansky, Pieter G. Kik

Faculty Bibliography 2000s

Surface plasmon excitation using resonant metal nanoparticles is studied experimentally. Geometry dependent reflection measurements reveal the existence of several optical resonances. Strong coupling of the in-plane nanoparticle plasmon resonance and propagating plasmons is evident from clear anticrossing behavior. Reflection measurements at high numerical aperture demonstrate the excitation of surface plasmons via out-of-plane particle polarization. The thus excited plasmons do not exhibit anticrossing in the considered frequency range. The results are explained in terms of the known surface plasmon dispersion relation and the anisotropic frequency dependent nanoparticle polarizability. These findings are important for applications utilizing surface-coupled nanoparticle plasmon resonances.

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Excitation Of Propagating Surface Plasmons By A Periodic Nanoparticle Array: Trade-Off Between Particle-Induced Near-Field Excitation And Damping, Amitabh Ghoshal, Pieter G. Kik Jan 2009

Excitation Of Propagating Surface Plasmons By A Periodic Nanoparticle Array: Trade-Off Between Particle-Induced Near-Field Excitation And Damping, Amitabh Ghoshal, Pieter G. Kik

Faculty Bibliography 2000s

The excitation of propagating surface plasmons (SPs) on a silver-silica interface by an array of ellipsoidal silver nanoparticles is investigated using numerical simulations as a function of particle volume for three different nanoparticle aspect ratios with representative resonance frequencies. We find that while the SP amplitude depends sensitively on particle volume for each selected aspect ratio, the maximum SP amplitude obtained for the different particle shapes is remarkably similar. These observations are explained in terms of particle-mediated SP excitation, counteracted by a size dependent particle-induced damping. An analytical model is presented that quantitatively describes the observed trends in SP damping.

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Binary And Ternary Recombination Of D-3(+) Ions With Electrons In He-D-2 Plasma, J. Glosík, I. Korolov, R. Plašil, T. Kotrík, P. Dohnal, O. Novotný, J. Varju, Š. Roucka, Chris H. Greene, V. Kokoouline Jan 2009

Binary And Ternary Recombination Of D-3(+) Ions With Electrons In He-D-2 Plasma, J. Glosík, I. Korolov, R. Plašil, T. Kotrík, P. Dohnal, O. Novotný, J. Varju, Š. Roucka, Chris H. Greene, V. Kokoouline

Faculty Bibliography 2000s

An experimental study is reported about the recombination of D-3(+) ions with electrons in a low-temperature plasma (200-300K) consisting of He with a small admixture of D-2. At several temperatures, the pressure dependence of the apparent binary recombination rate coefficient (alpha(eff)) was measured over a broad range of helium pressures (200-2000 Pa). The binary and ternary recombination rate coefficients were obtained from measured pressure dependences of alpha(eff). The binary recombination rate coefficient obtained alpha(bin)(300 K) = (2.7 +/- 0.9) x 10(-8) cm(3) s(-1) is in agreement with recent theory. The ternary recombination rate coefficient obtained is K-He(300 K) = (1.8 …

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Decorin Is A Novel Antagonistic Ligand Of The Met Receptor, Silvia Goldoni, Ashley Humphries, Alexander Nyström, Sampurna Sattar, Rick T. Owens, David J. Mcquillan, Keith Ireton, Renato V. Iozzo Jan 2009

Decorin Is A Novel Antagonistic Ligand Of The Met Receptor, Silvia Goldoni, Ashley Humphries, Alexander Nyström, Sampurna Sattar, Rick T. Owens, David J. Mcquillan, Keith Ireton, Renato V. Iozzo

Faculty Bibliography 2000s

Decorin, a member of the small leucine-rich proteoglycan gene family, impedes tumor cell growth by down-regulating the epidermal growth factor receptor. Decorin has a complex binding repertoire, thus, we predicted that decorin would modulate the bioactivity of other tyrosine kinase receptors. We discovered that decorin binds directly and with high affinity (K(d) = similar to 1.5 nM) to Met, the receptor for hepatocyte growth factor (HGF). Binding of decorin to Met is efficiently displaced by HGF and less efficiently by internalin B, a bacterial Met ligand. Interaction of decorin with Met induces transient receptor activation, recruitment of the E3 ubiquitin …

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A Novel Mode Of Translocation For Cytolethal Distending Toxin, Lina Guerra, Kathleen N. Nemec, Shane Massey, Suren A. Tatulian, Monica Thelestam, Teresa Frisan, Ken Teter Jan 2009

A Novel Mode Of Translocation For Cytolethal Distending Toxin, Lina Guerra, Kathleen N. Nemec, Shane Massey, Suren A. Tatulian, Monica Thelestam, Teresa Frisan, Ken Teter

Faculty Bibliography 2000s

Thermal instability in the toxin catalytic subunit may be a common property of toxins that exit the endoplasmic reticulum (ER) by exploiting the mechanism of ER-associated degradation (ERAD). The Haemophilus ducreyi cytolethal distending toxin (HdCDT) does not utilize ERAD to exit the ER, so we predicted the structural properties of its catalytic subunit (HdCdtB) would differ from other ER-translocating toxins. Here, we document the heat-stable properties of HdCdtB which distinguish it from other ER-translocating toxins. Cell-based assays further suggested that HdCdtB does not unfold before exiting the ER and that it may move directly from the ER lumen to the …

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Cooperation Enforcement In A Highly Dynamic Mobile Ad Hoc Network, Yao H. Ho, Ai Hua Ho, Kien A. Hua, Fei Xie Jan 2009

Cooperation Enforcement In A Highly Dynamic Mobile Ad Hoc Network, Yao H. Ho, Ai Hua Ho, Kien A. Hua, Fei Xie

Faculty Bibliography 2000s

Operations of mobile ad hoc networks rely on the collaboration of participating nodes to route data for each other. This standard approach using a fixed set of nodes for each communication link cannot cope with high mobility due to a high frequency of link breaks. A recent approach based on virtual routers has been proposed to address this problem. In this new environment, virtual routers are used for forwarding data. The functionality of each virtual router is provided by the mobile devices currently within its spatial proximity. Since these routers do not move, the communication links are much more robust …

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Albedos Of Main-Belt Comets 133p/Elst-Pizarro And 176p/Linear, Henry H. Hsieh, David Jewitt, Yanga R. Fernández Jan 2009

Albedos Of Main-Belt Comets 133p/Elst-Pizarro And 176p/Linear, Henry H. Hsieh, David Jewitt, Yanga R. Fernández

Faculty Bibliography 2000s

We present the determination of the geometric R-band albedos of two main-belt comet (MBC) nuclei based on data from the Spitzer Space Telescope and a number of ground-based optical facilities. For 133P/Elst-Pizarro, we find an albedo of p(R) = 0.05 +/- 0.02 and an effective radius of r(e) = 1.9 +/- 0.3 km (estimated semiaxes of a similar to 2.3 km and b similar to 1.6 km). For 176P/LINEAR, we find an albedo of p(R) = 0.06 +/- 0.02 and an effective radius of r(e) = 2.0 +/- 0.2 km (estimated semiaxes of a similar to 2.6 km and b …

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