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Spatially Inhomogeneous Linear Inverse Problems With Possible Singularities, Marianna Pensky Jan 2013

Spatially Inhomogeneous Linear Inverse Problems With Possible Singularities, Marianna Pensky

Faculty Bibliography 2010s

The objective of the present paper is to introduce the concept of a spatially inhomogeneous linear inverse problem where the degree of ill-posedness of operator Q depends not only on the scale but also on location. In this case, the rates of convergence are determined by the interaction of four parameters, the smoothness and spatial homogeneity of the unknown function f and degrees of ill-posedness and spatial inhomogeneity of operator Q. Estimators obtained in the paper are based either on wavelet-vaguelette decomposition (if the norms of all vaguelettes are finite) or on a hybrid of wavelet-vaguelette decomposition and Galerkin method …

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Discrete-Like Diffraction Dynamics In Free Space, Armando Perez-Leija, Francisco Soto-Eguibar, Sabino Chavez-Cerda, Alexander Szameit, Hector Moya-Cessa, Demetrios N. Christodoulides Jan 2013

Discrete-Like Diffraction Dynamics In Free Space, Armando Perez-Leija, Francisco Soto-Eguibar, Sabino Chavez-Cerda, Alexander Szameit, Hector Moya-Cessa, Demetrios N. Christodoulides

Faculty Bibliography 2010s

We introduce a new class of paraxial optical beams exhibiting discrete-like diffraction patterns reminiscent to those observed in periodic evanescently coupled waveguide lattices. It is demonstrated that such paraxial beams are analytically described in terms of generalized Bessel functions. Such effects are elucidated via pertinent examples.

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Influence Of Internal Heat Generation/Absorption, Thermal Radiation, Magnetic Field, Variable Fluid Property And Viscous Dissipation On Heat Transfer Characteristics Of A Maxwell Fluid Over A Stretching Sheet, K. V. Prasad, K. Vajravelu, A. Sujatha Jan 2013

Influence Of Internal Heat Generation/Absorption, Thermal Radiation, Magnetic Field, Variable Fluid Property And Viscous Dissipation On Heat Transfer Characteristics Of A Maxwell Fluid Over A Stretching Sheet, K. V. Prasad, K. Vajravelu, A. Sujatha

Faculty Bibliography 2010s

The present study investigates the effects of internal heat generation/absorption, thermal radiation, magnetic field, and temperature-dependent thermal conductivity on the flow and heat transfer characteristics of a Non-Newtonian Maxwell fluid over a stretching sheet. The upper convected Maxwell fluid model is used to characterize the non-Newtonian fluid behavior. Similarity solutions for the governing equations are obtained with prescribed surface temperature (PST) and/or with prescribed surface heat flux (PHF). Numerical solutions for the governing equations subject to the appropriate boundary conditions are obtained by a finite difference scheme known as Keller-Box method. The numerical results thus obtained are analyzed for the …

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Global Stability Of Infectious Disease Models Using Lyapunov Functions, Zhisheng Shuai, P. Van Den Driessche Jan 2013

Global Stability Of Infectious Disease Models Using Lyapunov Functions, Zhisheng Shuai, P. Van Den Driessche

Faculty Bibliography 2010s

Two systematic methods are presented to guide the construction of Lyapunov functions for general infectious disease models and are thus applicable to establish their global dynamics. Specifically, a matrix-theoretic method using the Perron eigenvector is applied to prove the global stability of the disease-free equilibrium, while a graph-theoretic method based on Kirchhoff's matrix tree theorem and two new combinatorial identities are used to prove the global stability of the endemic equilibrium. Several disease models in the literature and two new cholera models are used to demonstrate the applications of these methods.

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Linear-Quadratic Optimal Control Problems For Mean-Field Stochastic Differential Equations, Jiongmin Yong Jan 2013

Linear-Quadratic Optimal Control Problems For Mean-Field Stochastic Differential Equations, Jiongmin Yong

Faculty Bibliography 2010s

Linear-quadratic optimal control problems are considered for mean-field stochastic differential equations with deterministic coefficients. By a variational method, the optimality system is derived, which is a linear mean-field forward-backward stochastic differential equation. Using a decoupling technique, two Riccati differential equations are obtained which are uniquely solvable under certain conditions. Then a feedback representation is obtained for the optimal control.

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Laplace Deconvolution With Noisy Observations, Felix Abramovich, Marianna Pensky, Yves Rozenholc Jan 2013

Laplace Deconvolution With Noisy Observations, Felix Abramovich, Marianna Pensky, Yves Rozenholc

Faculty Bibliography 2010s

In the present paper we consider Laplace deconvolution for discrete noisy data observed on the interval whose length T-n may increase with a sample size. Although this problem arises in a variety of applications, to the best of our knowledge, it has been given very little attention by the statistical community. Our objective is to fill this gap and provide statistical treatment of Laplace deconvolution problem with noisy discrete data. The main contribution of the paper is explicit construction of an asymptotically rate-optimal (in the minimax sense) Laplace deconvolution estimator which is adaptive to the regularity of the unknown function. …

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Anisotropic De-Noising In Functional Deconvolution Model With Dimension-Free Convergence Rates, Rida Benhaddou, Marianna Pensky, Dominique Picard Jan 2013

Anisotropic De-Noising In Functional Deconvolution Model With Dimension-Free Convergence Rates, Rida Benhaddou, Marianna Pensky, Dominique Picard

Faculty Bibliography 2010s

In the present paper we consider the problem of estimating a periodic (r + 1)-dimensional function f based on observations from its noisy convolution. We construct a wavelet estimator of f , derive minimax lower bounds for the L-2-risk when f belongs to a Besov ball of mixed smoothness and demonstrate that the wavelet estimator is adaptive and asymptotically near-optimal within a logarithmic factor, in a wide range of Besov balls. We prove in particular that choosing this type of mixed smoothness leads to rates of convergence which are free of the curse of dimensionality and, hence, are higher than …

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Multi-Decadal Mangrove Forest Change Detection And Prediction In Honduras, Central America, With Landsat Imagery And A Markov Chain Model, Chi-Farn Chen, Nguyen-Thanh Son, Ni-Bin Chang, Cheng-Ru Chen, Li-Yu Chang, Miguel Valdez, Gustavo Centeno, Carlos Alberto Thompson, Jorge Luis Aceituno Jan 2013

Multi-Decadal Mangrove Forest Change Detection And Prediction In Honduras, Central America, With Landsat Imagery And A Markov Chain Model, Chi-Farn Chen, Nguyen-Thanh Son, Ni-Bin Chang, Cheng-Ru Chen, Li-Yu Chang, Miguel Valdez, Gustavo Centeno, Carlos Alberto Thompson, Jorge Luis Aceituno

Faculty Bibliography 2010s

Mangrove forests play an important role in providing ecological and socioeconomic services for human society. Coastal development, which converts mangrove forests to other land uses, has often ignored the services that mangrove may provide, leading to irreversible environmental degradation. Monitoring the spatiotemporal distribution of mangrove forests is thus critical for natural resources management of mangrove ecosystems. This study investigates spatiotemporal changes in Honduran mangrove forests using Landsat imagery during the periods 1985-1996, 1996-2002, and 2002-2013. The future trend of mangrove forest changes was projected by a Markov chain model to support decision-making for coastal management. The remote sensing data were …

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Hidden Symmetry Subgroup Problems, Thomas Decker, Gábor Ivanyos, Miklos Santha, University Of Central Florida Jan 2013

Hidden Symmetry Subgroup Problems, Thomas Decker, Gábor Ivanyos, Miklos Santha, University Of Central Florida

Faculty Bibliography 2010s

We advocate a new approach for addressing hidden structure problems and finding efficient quantum algorithms. We introduce and investigate the hidden symmetry subgroup problem (HSSP), which is a generalization of the well-studied hidden subgroup problem (HSP). Given a group acting on a set and an oracle whose level sets define a partition of the set, the task is to recover the subgroup of symmetries of this partition inside the group. The HSSP provides a unifying framework that, besides the HSP, encompasses a wide range of algebraic oracle problems, including quadratic hidden polynomial problems. While the HSSP can have provably exponential …

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Identification Of Snp-Containing Regulatory Motifs In The Myelodysplastic Syndromes Model Using Snp Arrays Ad Gene Expression Arrays, Jing Fan, Jennifer G. Dy, Chung-Che Chang, Xiaoboo Zhou Jan 2013

Identification Of Snp-Containing Regulatory Motifs In The Myelodysplastic Syndromes Model Using Snp Arrays Ad Gene Expression Arrays, Jing Fan, Jennifer G. Dy, Chung-Che Chang, Xiaoboo Zhou

Faculty Bibliography 2010s

Myelodysplastic syndromes have increased in frequency and incidence in the American population, but patient prognosis has not significantly improved over the last decade. Such improvements could be realized if biomarkers for accurate diagnosis and prognostic stratification were successfully identified. In this study, we propose a method that associates two state-of-the-art array technologies-single nucleotide polymor-phism (SNP) array and gene expression array-with gene motifs considered transcription factor-binding sites (TFBS). We are particularly interested in SNP-containing motifs introduced by genetic variation and mutation as TFBS. The potential regulation of SNP-containing motifs affects only when certain mutations occur. These motifs can be identified from …

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Incorporating Phylogenetic-Based Covarying Mutations Into Rnaalifold For Rna Consensus Structure Prediction, Ping Ge, Shaojie Zhang Jan 2013

Incorporating Phylogenetic-Based Covarying Mutations Into Rnaalifold For Rna Consensus Structure Prediction, Ping Ge, Shaojie Zhang

Faculty Bibliography 2010s

Background: RNAalifold, a popular computational method for RNA consensus structure prediction, incorporates covarying mutations into a thermodynamic model to fold the aligned RNA sequences. When quantifying covariance, it evaluates conserved signals of two aligned columns with base-pairing rules. This scoring scheme performs better than some other approaches, such as mutual information. However it ignores the phylogenetic history of the aligned sequences, which is an important criterion to evaluate the level of sequence covariance. Results: In this article, in order to improve the accuracy of consensus structure folding, we propose a novel approach named PhyloRNAalifold. It incorporates the number of covarying …

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Numerical And Analytical Methods For Variational Inequalities And Related Problems 2013, Zhenyu Huang, Ram N. Mohapatra, Shih-Sen Change, Qingzhi Yang Jan 2013

Numerical And Analytical Methods For Variational Inequalities And Related Problems 2013, Zhenyu Huang, Ram N. Mohapatra, Shih-Sen Change, Qingzhi Yang

Faculty Bibliography 2010s

No abstract provided.

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A Dynamic Enrollment Simulation Model For Planning And Decision-Making In A University, Luis Robledo Jan 2013

A Dynamic Enrollment Simulation Model For Planning And Decision-Making In A University, Luis Robledo

Electronic Theses and Dissertations

Decision support systems for university management have had limited improvement in the incorporation of new cutting-edge techniques. Most decisionmakers use traditional forecasting methods to base their decisions in order to maintain financially affordable programs and keep universities competitive for the last few decades. Strategic planning for universities has always been related to enrollment revenues, and operational expenses. Enrollment models in use today are able to represent forecasting based on historical data, considering usual variables like student headcount, student credit, among others. No consideration is given to students’ preferences. Retention models, associated to enrollment, deal with average retention times leaving off …

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Sustainability Analysis Of Intelligent Transportation Systems, Tolga Ercan Jan 2013

Sustainability Analysis Of Intelligent Transportation Systems, Tolga Ercan

Electronic Theses and Dissertations

Commuters in urban areas suffer from traffic congestion on a daily basis. The increasing number of vehicles and vehicle miles traveled (VMT) are exacerbating this congested roadway problem for society. Although literature contains numerous studies that strive to propose solutions to this congestion problem, the problem is still prevalent today. Traffic congestion problem affects society’s quality of life socially, economically, and environmentally. In order to alleviate the unsustainable impacts of the congested roadway problem, Intelligent Transportation Systems (ITS) has been utilized to improve sustainable transportation systems in the world. The purpose of this thesis is to analyze the sustainable impacts …

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Growth And Characterization Of Zno Based Semiconductor Materials And Devices, Ming Wei Jan 2013

Growth And Characterization Of Zno Based Semiconductor Materials And Devices, Ming Wei

Electronic Theses and Dissertations

Wide band gap semiconductors such as MgxZn1-xO represent an excellent choice for making optical photodetectors and emitters operating in the UV spectral region. High crystal and optical quality MgxZn1-xO thin films were grown epitaxially on c-plane sapphire substrates by plasma-assisted Molecular Beam Epitaxy. ZnO thin films with high crystalline quality, low defect and dislocation densities, and sub-nanometer surface roughness were achieved by applying a low temperature nucleation layer. The critical growth conditions were discussed to obtain a high quality film: the sequence of Zn and O sources for initial growth of nucleation layer, growth temperatures for both ZnO nucleation and …

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High School Students Attending College: A Study Of The Dual Enrollment Program And Its Impact On The Postsecondary Institution Of Brevard Community College, Matthew Hiesterman Jan 2013

High School Students Attending College: A Study Of The Dual Enrollment Program And Its Impact On The Postsecondary Institution Of Brevard Community College, Matthew Hiesterman

Electronic Theses and Dissertations

This study looks at the dual enrollment program at Brevard Community College in the state of Florida. It uses new interview data to determine if the positive and negative aspects of the program established by the literature still pertain. Four main themes were identified by the study of dual enrollment students and the postsecondary institution: money, quality of students, quantity of students, and opportunities of students and the institution. A discussion of each side of the discourse are made in order to help the program retain its positive attributes. While quality, quantity, and money are all issues concerning the day …

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Sparse Ridge Fusion For Linear Regression, Nozad Mahmood Jan 2013

Sparse Ridge Fusion For Linear Regression, Nozad Mahmood

Electronic Theses and Dissertations

For a linear regression, the traditional technique deals with a case where the number of observations n more than the number of predictor variables p (n > p). In the case n < p, the classical method fails to estimate the coefficients. A solution of the problem is the case of correlated predictors is provided in this thesis. A new regularization and variable selection is proposed under the name of Sparse Ridge Fusion (SRF). In the case of highly correlated predictor, the simulated examples and a real data show that the SRF always outperforms the lasso, eleastic net, and the S-Lasso, and the results show that the SRF selects more predictor variables than the sample size n while the maximum selected variables by lasso is n size.

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Efficient Alignment Of Rna Secondary Structures Using Sparse Dynamic Programming, Cuncong Zhong, Shaojie Zhang Jan 2013

Efficient Alignment Of Rna Secondary Structures Using Sparse Dynamic Programming, Cuncong Zhong, Shaojie Zhang

Faculty Bibliography 2010s

Background: Current advances of the next-generation sequencing technology have revealed a large number of un-annotated RNA transcripts. Comparative study of the RNA structurome is an important approach to assess their biological functionalities. Due to the large sizes and abundance of the RNA transcripts, an efficient and accurate RNA structure-structure alignment algorithm is in urgent need to facilitate the comparative study. Despite the importance of the RNA secondary structure alignment problem, there are no computational tools available that provide high computational efficiency and accuracy. In this case, designing and implementing such an efficient and accurate RNA secondary structure alignment algorithm is …

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Thermal Emission At 3.6-8 Mu M From Wasp-19b: A Hot Jupiter Without A Stratosphere Orbiting An Active Star, D. R. Anderson, A. M. S. Smith, N. Madhusudhan, P. J. Wheatley, A. Collier Cameron, C. Hellier, C. Campo, M. Gillon, Joseph Harrington, P. F. L. Maxted, D. Pollacco, D. Queloz, B. Smalley, A. H. M. J. Triaud, R. G. West Jan 2013

Thermal Emission At 3.6-8 Mu M From Wasp-19b: A Hot Jupiter Without A Stratosphere Orbiting An Active Star, D. R. Anderson, A. M. S. Smith, N. Madhusudhan, P. J. Wheatley, A. Collier Cameron, C. Hellier, C. Campo, M. Gillon, Joseph Harrington, P. F. L. Maxted, D. Pollacco, D. Queloz, B. Smalley, A. H. M. J. Triaud, R. G. West

Faculty Bibliography 2010s

We report detection of thermal emission from the exoplanet WASP-19b at 3.6, 4.5, 5.8 and 8.0 mu m. We used the InfraRed Array Camera on the Spitzer Space Telescope to observe two occultations of WASP-19b by its host star. We combine our new detections with previous measurements of WASP-19b's emission at 1.6 and 2.09 mu m to construct a spectral energy distribution of the planet's dayside atmosphere. By comparing this with model-atmosphere spectra, we find that the dayside atmosphere of WASP-19b lacks a strong temperature inversion. As WASP-19 is an active star (log R'(HK) = -4.50 +/- 0.03), this finding …

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Well-Posed And Ill-Posed Boundary Value Problems For Pde 2013, Allaberen Ashyralyev, Sergey Piskarev, Valery Covachev, Ravshan Ashurov, Hasan Ali Yurtsever, Abdullah Said Erdogan Jan 2013

Well-Posed And Ill-Posed Boundary Value Problems For Pde 2013, Allaberen Ashyralyev, Sergey Piskarev, Valery Covachev, Ravshan Ashurov, Hasan Ali Yurtsever, Abdullah Said Erdogan

Faculty Bibliography 2010s

No abstract provided.

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Centaurs And Scattered Disk Objects In The Thermal Infrared: Analysis Of Wise-Neowise Observations, James M. Bauer, Tommy Grav, Erin Blauvelt, A. K. Mainzer, Joseph R. Masiero, Rachel Stevenson, Emily Kramer, Yan R. Fernández, C. M. Lisse, Roc M. Cutri, Paul R. Weissman, John W. Dailey, Frank J. Masci, Russel Walker, Adam Waszczak, Carrie R. Nugent, Karen J. Meech, Andrew Lucas, George Pearman, Ashlee Wilkins, Jessica Watkins, Shrinivas Kulkarni, Edward L. Wright Jan 2013

Centaurs And Scattered Disk Objects In The Thermal Infrared: Analysis Of Wise-Neowise Observations, James M. Bauer, Tommy Grav, Erin Blauvelt, A. K. Mainzer, Joseph R. Masiero, Rachel Stevenson, Emily Kramer, Yan R. Fernández, C. M. Lisse, Roc M. Cutri, Paul R. Weissman, John W. Dailey, Frank J. Masci, Russel Walker, Adam Waszczak, Carrie R. Nugent, Karen J. Meech, Andrew Lucas, George Pearman, Ashlee Wilkins, Jessica Watkins, Shrinivas Kulkarni, Edward L. Wright

Faculty Bibliography 2010s

The Wide-field Infrared Survey Explorer (WISE) observed 52 Centaurs and scattered disk objects (SDOs) in the thermal infrared, including 15 new discoveries. We present analyses of these observations to estimate sizes and mean optical albedos. We find mean albedos of 0.08 +/- 0.04 for the entire data set. Thermal fits yield average beaming parameters of 0.9 +/- 0.2 that are similar for both SDO and Centaur sub-classes. Biased cumulative size distributions yield size-frequency distribution power law indices of similar to-1.7 +/- 0.3. The data also reveal a relation between albedo and color at the 3 sigma level. No significant relation …

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Evaluating The Effect Of Partial Contributing Storage On The Storage-Discharge Function From Recession Analysis, X. Chen, D. Wang Jan 2013

Evaluating The Effect Of Partial Contributing Storage On The Storage-Discharge Function From Recession Analysis, X. Chen, D. Wang

Faculty Bibliography 2010s

Hydrograph recession during dry periods has been used to construct water storage-discharge relationships and to quantify storage dynamics and evaporation when streamflow data is available. However, variable hydrologic connectivity among hillslope-riparian-stream zones may affect the lumped storage-discharge relationship, and as a result, affect the estimation of evaporation and storage change. Given observations of rainfall and runoff, and remote-sensing-based observations of evaporation, the ratio (alpha) between estimated daily evaporation from recession analysis and observed evaporation, and the ratio (beta) between estimated contributing storage and total watershed storage are computed for 9 watersheds located in different climate regions. Both evaporation and storage …

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Crystallographic Anisotropy Of The Resistivity Size Effect In Single Crystal Tungsten Nanowires, Dooho Choi, Matthew Moneck, Xuan Liu, Soong Ju Oh, Cherie R. Kagan, Kevin R. Coffey, Katayun Barmak Jan 2013

Crystallographic Anisotropy Of The Resistivity Size Effect In Single Crystal Tungsten Nanowires, Dooho Choi, Matthew Moneck, Xuan Liu, Soong Ju Oh, Cherie R. Kagan, Kevin R. Coffey, Katayun Barmak

Faculty Bibliography 2010s

This work demonstrates an anisotropic increase in resistivity with decreasing width in single crystal tungsten (W) nanowires having a height of 21 nm. Nanowire-widths were in the range of 15-451 nm, with the anisotropy observed for widths below 50 nm. The longitudinal directions of the nanowires coincided with the < 100 >, < 110 > and < 111 > orientations of the body centered cubic phase of W. The resistivity increase was observed to be minimized for the < 111 > -oriented single crystal nanowires, exhibiting a factor of two lower increase in resistivity at a width of similar to 15 nm, relative to the thin film resistivity (i.e., an infinitely …

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Mmp-3 Contributes To Nigrostriatal Dopaminergic Neuronal Loss, Bbb Damage, And Neuroinflammation In An Mptp Mouse Model Of Parkinson's Disease, Young Cheul Chung, Yoon-Seong Kim, Eugene Bok, Tae Young Yune, Sungho Maeng, Byung Kwan Jin Jan 2013

Mmp-3 Contributes To Nigrostriatal Dopaminergic Neuronal Loss, Bbb Damage, And Neuroinflammation In An Mptp Mouse Model Of Parkinson's Disease, Young Cheul Chung, Yoon-Seong Kim, Eugene Bok, Tae Young Yune, Sungho Maeng, Byung Kwan Jin

Faculty Bibliography 2010s

The present study examined whether matrix metalloproteinase-3 (MMP-3) participates in the loss of dopaminergic (DA) neurons in the nigrostriatal pathway in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of Parkinson's disease with blood brain barrier (BBB) damage and infiltration of peripheral immune cells. Tyrosine hydroxylase (TH) immunostaining of brain sections from MPTP-treated mice showed that MPTP induced significant degeneration of nigrostriatal DA neurons. Moreover, FITC-labeled albumin detection and immunostaining revealed that MPTP caused damage to the BBB and increased the number of ED-1- and CD-3-immunopositive cells in the substantia nigra (SN). Genetic ablation of MMP-3 reduced the nigrostriatal DA neuron loss and …

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Isospectral Measures, Dorin Ervin Dutkay, Palle E.T. Jorgensen Jan 2013

Isospectral Measures, Dorin Ervin Dutkay, Palle E.T. Jorgensen

Faculty Bibliography 2010s

In recent papers a number of authors have considered Borel probability measures mu in R-d such that the Hilbert space L-2(mu) has a Fourier basis (orthogonal) of complex exponentials. If mu satisfies this property, the set of frequencies in this set is called a spectrum for mu. Here we fix a spectrum, say G, and we study the possibilities for measures mu having G as spectrum.

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Edge Dominating Sets And Vertex Covers, Ronald Dutton, William F. Klostermeyer Jan 2013

Edge Dominating Sets And Vertex Covers, Ronald Dutton, William F. Klostermeyer

Faculty Bibliography 2010s

Bipartite graphs with equal edge domination number and maximum matching cardinality are characterized. These two parameters are used to develop bounds on the vertex cover and total vertex cover numbers of graphs and a resulting chain of vertex covering, edge domination, and matching parameters is explored. In addition, the total vertex cover number is compared to the total domination number of trees and grid graphs.

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Mobility Transition From Ballistic To Diffusive Transport In Non-Hermitian Lattices, T. Eichelkraut, R. Heilmann, S. Weimann, Simon Stützer, Felix Dreisow, Demetrios N. Christodoulides, Stefan Nolte, Alexander Szameit Jan 2013

Mobility Transition From Ballistic To Diffusive Transport In Non-Hermitian Lattices, T. Eichelkraut, R. Heilmann, S. Weimann, Simon Stützer, Felix Dreisow, Demetrios N. Christodoulides, Stefan Nolte, Alexander Szameit

Faculty Bibliography 2010s

Within all physical disciplines, it is accepted that wave transport is predetermined by the existence of disorder. In this vein, it is known that ballistic transport is possible only when a structure is ordered, and that disorder is crucial for diffusion or (Anderson-)localization to occur. As this commonly accepted picture is based on the very foundations of quantum mechanics where Hermiticity of the Hamiltonian is naturally assumed, the question arises whether these concepts of transport hold true within the more general context of non-Hermitian systems. Here we demonstrate theoretically and experimentally that in ordered time-independent PT-symmetric systems, which are symmetric …

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Seasonality Influences Cuticle Melanization And Immune Defense In A Cricket: Support For A Temperature-Dependent Immune Investment Hypothesis In Insects, Kenneth M. Fedorka, Emily K. Copeland, Wade E. Winterhalter Jan 2013

Seasonality Influences Cuticle Melanization And Immune Defense In A Cricket: Support For A Temperature-Dependent Immune Investment Hypothesis In Insects, Kenneth M. Fedorka, Emily K. Copeland, Wade E. Winterhalter

Faculty Bibliography 2010s

To improve thermoregulation in colder environments, insects are expected to darken their cuticles with melanin via the phenoloxidase cascade, a phenomenon predicted by the thermal melanin hypothesis. However, the phenoloxidase cascade also plays a significant role in insect immunity, leading to the additional hypothesis that the thermal environment indirectly shapes immune function via direct selection on cuticle color. Support for the latter hypothesis comes from the cricket Allonemobius socius, where cuticle darkness and immune-related phenoloxidase activity increase with latitude. However, thermal environments vary seasonally as well as geographically, suggesting that seasonal plasticity in immunity may also exist. Although seasonal fluctuations …

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Helicobacter Pylori Infection And Light Chain Gammopathy, José A. Girón, Shawn L. Shah Jan 2013

Helicobacter Pylori Infection And Light Chain Gammopathy, José A. Girón, Shawn L. Shah

Faculty Bibliography 2010s

Objective. Helicobacter pylori provokes a host of immune alterations upon colonizing the gastric mucosa. Design. We report 22 individuals with confirmed Helicobacter pylori infection who were also managed for the concurrent elevation of immunoglobulin free light chain (kappa and lambda) levels. Result. Of the 22 patients, 15 patients (68.2%) had elevated free light chain levels: 6 patients (40%) had only kappa chain elevation, 2 patients (13.3%) had only lambda chain elevation, and 7 patients (46.7%) had both kappa and lambda chain elevation. Twenty out of the 22 patients (90.9%) were microbiologically confirmed cured with 3 patients being lost to follow-up …

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Shockwave Based Nonlinear Optical Manipulation In Densely Scattering Opaque Suspensions, Elad Greenfield, Jonathan Nemirovsky, Ramy El-Ganainy, Demetri N. Christodoulides, Mordechai Segev Jan 2013

Shockwave Based Nonlinear Optical Manipulation In Densely Scattering Opaque Suspensions, Elad Greenfield, Jonathan Nemirovsky, Ramy El-Ganainy, Demetri N. Christodoulides, Mordechai Segev

Faculty Bibliography 2010s

Optical manipulation of particulate-loaded, highly scattering (opaque) suspensions is considered impossible. Here we demonstrate theoretically and experimentally optical manipulation of the local properties of such opaque suspensions. We show that the optical forces exerted by multiply-scattered light give rise to dense shock fronts of particle concentration, propagating deep inside the opaque suspensions, where the optical field is completely diffuse. We exploit these waves to demonstrate a plethora of optofluidic manipulations, ranging from optical transport and concentration of large populations of nanoparticles, to light-induced 'writing' of concentrated spots in the suspensions and light-induced phase-transition from suspension to gel in localized volumes …

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