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2010

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On A Generalized Time-Varying Seir Epidemic Model With Mixed Point And Distributed Time-Varying Delays And Combined Regular And Impulsive Vaccination Controls, Ravi P. Agarwal, Manuel De La Sen, Asier Ibeas, Santiago Alonso-Quesada Dec 2010

On A Generalized Time-Varying Seir Epidemic Model With Mixed Point And Distributed Time-Varying Delays And Combined Regular And Impulsive Vaccination Controls, Ravi P. Agarwal, Manuel De La Sen, Asier Ibeas, Santiago Alonso-Quesada

Mathematics and System Engineering Faculty Publications

This paper discusses a generalized time-varying SEIR propagation disease model subject to delays which potentially involves mixed regular and impulsive vaccination rules. The model takes also into account the natural population growing and the mortality associated to the disease, and the potential presence of disease endemic thresholds for both the infected and infectious population dynamics as well as the lost of immunity of newborns. The presence of outsider infectious is also considered. It is assumed that there is a finite number of time-varying distributed delays in the susceptible-infected coupling dynamics influencing the susceptible and infected differential equations. It is also …


Superhydrophobic Thin Films Fabricated By Reactive Layer-By-Layer Assembly Of Azlactone-Functionalized Polymers, Maren E. Buck, Sarina C. Schwartz, David M. Lynn Dec 2010

Superhydrophobic Thin Films Fabricated By Reactive Layer-By-Layer Assembly Of Azlactone-Functionalized Polymers, Maren E. Buck, Sarina C. Schwartz, David M. Lynn

Chemistry: Faculty Publications

We report an approach to the fabrication of superhydrophobic thin films that is based on the "reactive" layer-by-layer assembly of azlactone-containing polymer multilayers. We demonstrate that films fabricated from alternating layers of the azlactone functionalized polymer poly(2-vinyl- 4,4-dimethylazlactone) (PVDMA) and poly(ethyleneimine) (PEI) exhibit micro- and nanoscale surface features that result in water contact angles in excess of 150°. Our results reveal that the formation of these surface features is (i) dependent upon film thickness (i.e., the number of layers of PEI and PVDMA deposited) and (ii) that it is influenced strongly by the presence (or absence) of cyclic azlactone-functionalized oligomers …


Do Cosmological Perturbations Have Zero Mean?, Christian Armendariz-Picon Dec 2010

Do Cosmological Perturbations Have Zero Mean?, Christian Armendariz-Picon

Physics - All Scholarship

A central assumption in our analysis of cosmic structure is that cosmological perturbations have zero ensemble mean. This property is one of the consequences of statistically homogeneity, the invariance of correlation functions under spatial translations. In this article we explore whether cosmological perturbations indeed have zero mean, and thus test one aspect of statistical homogeneity. We carry out a classical test of the zero mean hypothesis against a class of alternatives in which perturbations have non-vanishing means, but homogeneous and isotropic covariances. Apart from Gaussianity, our test does not make any additional assumptions about the nature of the perturbations and …


Isomer-Dependent Adsorption And Release Of Cis- And Trans-Platin Anticancer Drugs By Mesopomus Silica Nanoparticles, Zhimin Tao, Youwei Xie, Jerry Goodisman, Tewodros Asefa Dec 2010

Isomer-Dependent Adsorption And Release Of Cis- And Trans-Platin Anticancer Drugs By Mesopomus Silica Nanoparticles, Zhimin Tao, Youwei Xie, Jerry Goodisman, Tewodros Asefa

Chemistry - All Scholarship

We report on adsorption and release of the anticancer drugs cisplatin and transplatin from mesoporous silica nanomaterials, emphasizing the differences between cisplatin and its much less toxic isomer. Two types of particles, M.CM-41 and SBA-IS, were used, either as just synthesized or after calcination to remove the templates. The particles were characterized by TEM, nitrogen physisorption, and elemental analysis. The UV-vis spectra of cisplatin and transplatin were obtained and the intensities of several bands (205-210 nm, 210-220 nm, 220-235 nm, and 300-330 nm) were found proportional to drug concentrations, allowing their use for measuring drug concentration. To evaluate drug adsorption …


Uncertainty Associated With Modeling The Global Ionosphere, Janelle V. Jenniges, Ariel O. Acebal, Larry Gardner, Robert W. Schunk, Lie Zhu Dec 2010

Uncertainty Associated With Modeling The Global Ionosphere, Janelle V. Jenniges, Ariel O. Acebal, Larry Gardner, Robert W. Schunk, Lie Zhu

Physics Student Research

A study has been conducted of the effect that different physical assumptions have on global models of the electron density distribution. The study was conducted with the Ionosphere Forecast Model (IFM) and the Ionosphere Plasmasphere Model (IPM) developed by Utah State University. Both physics-based, time-dependent, global models use the same empirical models for the neutral atmosphere (MSIS) and neutral wind (Horizontal Wind Model, HWM), but the altitude range, thermal structure, number of ion species, and magnetic 2ield are different. The IFM covers the altitude range from 90-1400 km, calculates the densities for four ions (NO+, O2+, N2+, O+), has a …


Paranets: A Parallel Network Architecture For The Future Internet, Khaled Harras, Abderrahmen Mtibaa Dec 2010

Paranets: A Parallel Network Architecture For The Future Internet, Khaled Harras, Abderrahmen Mtibaa

Computer Science Faculty Works

The evolution of networking technologies and portable devices has led users to expect connectivity anytime and everywhere. We have reached the point of seeing networking occur underwater, via aerial devices, and across space. While researchers push the true boundaries of networking to serve a wide range of environments, there is the challenge of providing robust network connectivity beyond the boundaries of the core internet, defined by fiber optics and well-organized backbones. As the internet edges expand, the expectation is that connectivity will be as good, in terms of high bandwidth and minimal interruption, as anywhere in the core. Such an …


Sources Of The Radio Background Considered, Jack Singal, L. Stawarz, A. Lawrence, V. Petrosian Dec 2010

Sources Of The Radio Background Considered, Jack Singal, L. Stawarz, A. Lawrence, V. Petrosian

Physics Faculty Publications

We investigate different scenarios for the origin of the extragalactic radio background. The surface brightness of the background, as reported by the Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission 2 (ARCADE 2) collaboration, is several times higher than that which would result from currently observed radio sources. We consider contributions to the background from diffuse synchrotron emission from clusters and the intergalactic medium, previously unrecognized flux from low-surface-brightness regions of radio sources and faint point sources below the flux limit of existing surveys. By examining radio source counts available in the literature, we conclude that most of the radio …


Nanoparticle Doped Photopolymer With Reduced Shrinkage For Holographic Recording, Mohesh Moothanchery, Svetlana Mintova, Izabela Naydenova, Vincent Toal Dec 2010

Nanoparticle Doped Photopolymer With Reduced Shrinkage For Holographic Recording, Mohesh Moothanchery, Svetlana Mintova, Izabela Naydenova, Vincent Toal

Conference Papers

We demonstrate holographic recording with Si-MFI zeolite doped acrylamide based photopolymerfilm. The influence of silicate nanoparticles on photopolymer shrinkage has been studied and compared withshrinkage in undoped photopolymer layers The shrinkage of the material (1.03%) is significantly lower forrecording in Si-MFI zeolite nanoparticle doped samples than for undoped layers (1.77%).


Classification Of Generalized Hadamard Matrices H(6,3) And Quaternary Hermitian Self-Dual Codes Of Length 18, Masaaki Harada, Clement Lam, Akihiro Munemasa, Vladimir Tonchev Dec 2010

Classification Of Generalized Hadamard Matrices H(6,3) And Quaternary Hermitian Self-Dual Codes Of Length 18, Masaaki Harada, Clement Lam, Akihiro Munemasa, Vladimir Tonchev

Department of Mathematical Sciences Publications

All generalized Hadamard matrices of order 18 over a group of order 3, H(6,3),are enumerated in two different ways: once, as class regular symmetric (6,3)-nets,or symmetric transversal designs on 54 points and 54 blocks with a group of order 3 acting semi-regularly on points and blocks, and secondly,as collections of fullweight vectors in quaternary Hermitian self-dual codes of length 18. The second enumeration is based on the classification of Hermitian self-dual [18,9] codes over GF(4), completed in this paper. It is shown that up to monomial equivalence, there are 85 generalized Hadamard matrices H(6,3), and 245 inequivalent Hermitian self-dual codes …


Late 20th Century Hydrologic Change In Western North America: Regional Impacts And The Role Of Climate, Shaleen Jain Dec 2010

Late 20th Century Hydrologic Change In Western North America: Regional Impacts And The Role Of Climate, Shaleen Jain

University of Maine Office of Research Administration: Grant Reports

Hydroclimatic variations and change directly impact the freshwater supplies in western North America. Streamflow in this region has shown increased variability of annual flow volumes and increasing synchroneity in the largest basins in the west towards the end of last century. As land-use change seems to play a lesser role, the PI will study the sensitivity of the western North American winter precipitation and related streamflow to El Nino-Southern Oscillation variations. The PI will use observations and multi-model ensemble integrations to study the decadal variations. The broader impact of this project will be an increase of the scientific knowledge required …


Retired A Stars And Their Companions. Vi. A Pair Of Interacting Exoplanet Pairs Around The Subgiants 24 Sextanis And Hd 200964*, John Asher Johnson, Matthew J. Payne, Andrew W. Howard, Kelsey I. Clubb, Eric B. Ford, Brendan P. Bowler, Gregory W. Henry, Debra A. Fischer, Geoffrey W. Marcy, John M. Brewer, Christian Schwab, Sabine Reffert, Thomas B. Lowe Dec 2010

Retired A Stars And Their Companions. Vi. A Pair Of Interacting Exoplanet Pairs Around The Subgiants 24 Sextanis And Hd 200964*, John Asher Johnson, Matthew J. Payne, Andrew W. Howard, Kelsey I. Clubb, Eric B. Ford, Brendan P. Bowler, Gregory W. Henry, Debra A. Fischer, Geoffrey W. Marcy, John M. Brewer, Christian Schwab, Sabine Reffert, Thomas B. Lowe

Information Systems and Engineering Management Research Publications

We report radial velocity (RV) measurements of the G-type subgiants 24 Sextanis (= HD 90043) and HD 200964. Both are massive, evolved stars that exhibit periodic variations due to the presence of a pair of Jovian planets. Photometric monitoring with the T12 0.80 m APT at Fairborn Observatory demonstrates both stars to be constant in brightness to ⩽0.002 mag, thus strengthening the planetary interpretation of the RV variations. Based on our dynamical analysis of the RV time series, 24 Sex b, c have orbital periods of 452.8 days and 883.0 days, corresponding to semimajor axes 1.333 AU and 2.08 AU, …


The Hanle Effect As A Diagnostic Of Magnetic Fields In Stellar Envelopes. V. Thin Lines From Keplerian Disks., Richard Ignace Dec 2010

The Hanle Effect As A Diagnostic Of Magnetic Fields In Stellar Envelopes. V. Thin Lines From Keplerian Disks., Richard Ignace

ETSU Faculty Works

This paper focuses on the polarized profiles of resonance scattering lines that form in magnetized disks. Optically thin lines from Keplerian planar disks are considered. Model line profiles are calculated for simple field topologies of axial fields (i.e., vertical to the disk plane) and toroidal fields (i.e., purely azimuthal). A scheme for discerning field strengths and geometries in disks is developed based on Stokes Q − U diagrams for the run of polarization across line profiles that are Doppler-broadened by the disk rotation. A discussion of the Hanle effect for magnetized disks in which the magnetorotational instability (MRI) is operating …


Graphs Of Bounded Degree And The P-Harmonic Boundary, Michael J. Puls Dec 2010

Graphs Of Bounded Degree And The P-Harmonic Boundary, Michael J. Puls

Publications and Research

Let p be a real number greater than one and let G be a connected graph of bounded degree. We introduce the p-harmonic boundary of G and use it to characterize the graphs G for which the constant functions are the only p-harmonic functions on G. We show that any continuous function on the p-harmonic boundary of G can be extended to a function that is p-harmonic on G. We also give some properties of this boundary that are preserved under rough-isometries. Now let Gamma be a finitely generated group. As an application of our results, we characterize the vanishing …


Double Compact Objects As Low-Frequency Gravitational Wave Sources, Krzysztof Belczynski, Matthew Benacquista, Tomasz Bulik Dec 2010

Double Compact Objects As Low-Frequency Gravitational Wave Sources, Krzysztof Belczynski, Matthew Benacquista, Tomasz Bulik

Physics and Astronomy Faculty Publications and Presentations

We study the Galactic field population of double compact objects (DCOs; NS-NS, BH-NS, BH-BH binaries) to investigate the number (if any) of these systems that can potentially be detected with the Laser Interferometer Space Antenna (LISA) at low gravitational wave frequencies. We calculate the Galactic numbers and physical properties of these binaries and show their relative contributions from the disk, bulge, and halo. Although the Galaxy hosts ∼10 5 DCO binaries emitting low-frequency gravitational waves, only a handful of these objects in the disk will be detectable with LISA, but none from the halo or bulge. This is because the …


Invasive Species And Climate Change, Invasive Species Advisory Committee Dec 2010

Invasive Species And Climate Change, Invasive Species Advisory Committee

National Invasive Species Council

ISSUE

Climate change interacts with and can often amplify the negative impacts of invasive species. These interactions are not fully appreciated or understood. They can result in threats to critical ecosystem functions on which our food system and other essential provisions and services depend as well as increase threats to human health. The Invasive Species Advisory Committee to the National Invasive Species Council recognizes the Administration’s commitment to dealing proactively with global climate change. However, unless we recognize and act on the impact of climate change and its interaction with ecosystems and invasive species, we will fall further behind in …


10th Annual Senior Research Symposium Of The Department Of Biological Sciences, Chemistry And Biochemistry, Messiah College Dec 2010

10th Annual Senior Research Symposium Of The Department Of Biological Sciences, Chemistry And Biochemistry, Messiah College

School of Science, Engineering & Health (SEH) Symposium

No abstract provided.


A Sequel To “A Space Topologized By Functions From Omega To Omega”, Tetsuya Ishiu, Akira Iwasa Dec 2010

A Sequel To “A Space Topologized By Functions From Omega To Omega”, Tetsuya Ishiu, Akira Iwasa

Faculty Publications

We consider a topological space ⟨𝑋, 𝜏 (ℱ)⟩, where 𝑋 = {𝑝 ∗} ∪ [𝜔 Å~ 𝜔] and ℱ ⊆ 𝜔𝜔. Each point in 𝜔 Å~ 𝜔 is isolated and a neighborhood of 𝑝∗ has the form {𝑝∗}∪{⟨𝑖, 𝑗⟩ : 𝑖 ≥ 𝑛, 𝑗 ≥ 𝑓(𝑖)} for some 𝑛 ∈ 𝜔 and 𝑓 ∈ ℱ. We show that there are subsets ℱ and 𝒢 of 𝜔𝜔 such that ℱ is not bounded, 𝒢 is bounded, yet ⟨𝑋, 𝜏 (ℱ)⟩ and ⟨𝑋, 𝜏 (𝒢)⟩ are homeomorphic. This answers a question of the second author posed in A space topologized by functions …


Automatic Media Segmentation Within Ieee 1599–2008, Antonello D'Aguanno, Luca A. Ludovico, Davide Andrea Mauro Dec 2010

Automatic Media Segmentation Within Ieee 1599–2008, Antonello D'Aguanno, Luca A. Ludovico, Davide Andrea Mauro

Computer Sciences and Electrical Engineering Faculty Research

This paper deals with the automatic extraction of synchronization data from IEEE 1599-2008, an XML-based standard aiming at a comprehensive description of music. Within such format, audio tracks and video contents related to the same music piece can be referred to the occurrence of symbolic music events. In this way, digital objects are mutually synchronized, too. The goal is to show how timing information can be easily extracted from an IEEE 1599-2008 file, converted into a suitable format, and finally employed in a multimedia editing environment in order to produce an automatic segmentation of media objects.


Estimating Potential Forest Npp, Biomass And Their Climatic Sensitivity In New England Using A Dynamic Ecosystem Model, Guoping Tang, Brian Beckage, Benjamin Smith, Paul A. Miller Dec 2010

Estimating Potential Forest Npp, Biomass And Their Climatic Sensitivity In New England Using A Dynamic Ecosystem Model, Guoping Tang, Brian Beckage, Benjamin Smith, Paul A. Miller

College of Agriculture and Life Sciences Faculty Publications

Accurate estimation of forest net primary productivity (NPP), biomass, and their sensitivity to changes in temperature and precipitation is important for understanding the fluxes and pools of terrestrial carbon resulting from anthropogenically driven climate change. The objectives of this study were to (1) estimate potential forest NPP and biomass for New England using a regional ecosystem model, (2) compare modeled forest NPP and biomass with other reported data for New England, and (3) examine the sensitivity of modeled forest NPP to historical climatic variation. We addressed these objectives using the regional ecosystem model LPJ-GUESS implemented with eight plant functional types …


Hybrid Micro-/Nanogels For Optical Sensing And Intracellular Imaging, Weitai Wu, Shuiqin Zhou Dec 2010

Hybrid Micro-/Nanogels For Optical Sensing And Intracellular Imaging, Weitai Wu, Shuiqin Zhou

Publications and Research

Hybrid micro-/nanogels are playing an increasing important part in a diverse range of applications, due to their tunable dimensions, large surface area, stable interior network structure, and a very short response time. We review recent advances and challenges in the developments of hybrid micro-/nanogels toward applications for optical sensing of pH, temperature, glucose, ions, and other species as well as for intracellular imaging. Due to their unique advantages, hybrid micro-/nanogels as optical probes are attracting substantial interests for continuous monitoring of chemical parameters in complex samples such as blood and bioreactor fluids, in chemical research and industry, and in food …


Ua1b1/3 University Lecture Series, Wku Archives Dec 2010

Ua1b1/3 University Lecture Series, Wku Archives

WKU Archives Collection Inventories

Records created by the University Lecture Series committee which invites distinguished and prominent individuals to lecture at the university. The records include correspondence with potential speakers and programs, posters and recordings of lectures.


Ua1b1/2 L.Y. Lancaster Lecture Series, Wku Archives Dec 2010

Ua1b1/2 L.Y. Lancaster Lecture Series, Wku Archives

WKU Archives Collection Inventories

Records regarding the L.Y. Lancaster Lecture Series.


Ua24 Mammoth Cave International Center For Science & Learning, Wku Archives Dec 2010

Ua24 Mammoth Cave International Center For Science & Learning, Wku Archives

WKU Archives Collection Inventories

Records created by and about the Mammoth Cave International Center for Science and Learning.


Erratum: Scaled Momentum Spectra In Deep Inelastic Scattering At Hera (Journal Of High Energy Physics (2010) 06 (009)), H. Abramowicz, I. Abt, L. Adamczyk, M. Adamus, S. Antonelli, P. Antonioli, A. Antonov, M. Arneodo, V. Aushev, Y. Aushev, O. Bachynska, A. Bamberger, A. N. Barakbaev, G. Barbagli, G. Bari, F. Barreiro, D. Bartsch, M. Basile, O. Behnke, J. Behr, U. Behrens, L. Bellagamba, A. Bertolin, S. Bhadra, M. Bindi, C. Blohm, T. Bołd, E. G. Boos, M. Borodin, K. Borras, D. Boscherini, Margarita C. K. Mattingly Dec 2010

Erratum: Scaled Momentum Spectra In Deep Inelastic Scattering At Hera (Journal Of High Energy Physics (2010) 06 (009)), H. Abramowicz, I. Abt, L. Adamczyk, M. Adamus, S. Antonelli, P. Antonioli, A. Antonov, M. Arneodo, V. Aushev, Y. Aushev, O. Bachynska, A. Bamberger, A. N. Barakbaev, G. Barbagli, G. Bari, F. Barreiro, D. Bartsch, M. Basile, O. Behnke, J. Behr, U. Behrens, L. Bellagamba, A. Bertolin, S. Bhadra, M. Bindi, C. Blohm, T. Bołd, E. G. Boos, M. Borodin, K. Borras, D. Boscherini, Margarita C. K. Mattingly

Faculty Publications

No abstract provided.


Interview With Brendan Phillips, Sisters Of The Road, 2010 (Audio), Brendan Phillips Dec 2010

Interview With Brendan Phillips, Sisters Of The Road, 2010 (Audio), Brendan Phillips

All Sustainability History Project Oral Histories

Interview of Brendan Phillips by Brandon Green in Portland, Oregon on December 8th, 2010.

The interview index is available for download.


Ua1c11/25 Lost River Cave Photo Collection, Wku Archives Dec 2010

Ua1c11/25 Lost River Cave Photo Collection, Wku Archives

WKU Archives Collection Inventories

Photographs and postcards created by Lost River Cave & Valley.


Global Dimension Of Ci: Compete Or Collaborate, Arden L. Bement Jr. Dec 2010

Global Dimension Of Ci: Compete Or Collaborate, Arden L. Bement Jr.

PPRI Digital Library

No abstract provided.


The Fierce Green Fire: Vol. 1 Issue 6, Wofford College Environmental Studies Program Dec 2010

The Fierce Green Fire: Vol. 1 Issue 6, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


Investigation Of Spatial And Temporal Processes Of Lake-Aquifer Interactions In The Nebraska Sand Hills, John T. Ong Dec 2010

Investigation Of Spatial And Temporal Processes Of Lake-Aquifer Interactions In The Nebraska Sand Hills, John T. Ong

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Interaction between surface water and groundwater is an important component of the water cycle that affects the physicochemical and biological characteristics of lakes, streams, wetlands, and seacoasts. Due to the complex interaction of geologic, topographic, and hydrologic factors, flow between lakes and groundwater remains poorly understood. Evolution of conceptual models over the past 30 years describes processes of advection, dispersion, and free convection that occur in different lake flow regimes. Few detailed field studies document the validity of these conceptual models because of the difficulty of studying the subsurface and the prohibitive cost of instrumenting large areas. In the semi-arid …


Direct Patterning Of Silanized-Biomolecules On Semiconductor Surfaces, Dorjderem Nyamjav, Richard C. Holz Dec 2010

Direct Patterning Of Silanized-Biomolecules On Semiconductor Surfaces, Dorjderem Nyamjav, Richard C. Holz

Chemistry Faculty Research and Publications

A novel approach to pattern silanized-biomolecules directly onto glass (SiOx) substrates via Dip-Pen nanolithography (DPN) and microcontact printing (μCP) is presented. Subsequent hybridization reactions of DPN patterned silanized-DNA with its complementary strands provide “proof-of-concept” that the patterned oligonucleotides maintain their biological activities. The fabrication strategy does not require premodification of substrates and offers a cheap and robust way to immobilize molecules on electronically important semiconductor surfaces.