Digital Commons Network^™

Estimating Epidemiological Parameters Of A Stochastic Differential Model Of Hiv Dynamics Using Hierarchical Bayesian Statistics, Renee Dale, Bei Bei Guo

Faculty Publications

Current estimates of the HIV epidemic indicate a decrease in the incidence of the disease in the undiagnosed subpopulation over the past 10 years. However, a lack of access to care has not been considered when modeling the population. Populations at high risk for contracting HIV are twice as likely to lack access to reliable medical care. In this paper, we consider three contributors to the HIV population dynamics: at-risk population exhaustion, lack of access to care, and usage of anti-retroviral therapy (ART) by diagnosed individuals. An extant problem in the mathematical study of this system is deriving parameter estimates …

Natively Oxidized Amino Acid Residues In The Spinach Cytochrome B6 F Complex, Ryan M. Taylor, Larry Sallans, Laurie K. Frankel, Terry M. Bricker

Faculty Publications

© 2018, Springer Science+Business Media B.V., part of Springer Nature. The cytochrome b6f complex of oxygenic photosynthesis produces substantial levels of reactive oxygen species (ROS). It has been observed that the ROS production rate by b6f is 10–20 fold higher than that observed for the analogous respiratory cytochrome bc1 complex. The types of ROS produced (O2•−, 1O2, and, possibly, H2O2) and the site(s) of ROS production within the b6f complex have been the subject of some debate. Proposed sources of ROS have included the heme bp, PQp•− (possible sources for O2•−), the Rieske iron–sulfur cluster (possible source of O2•− and/or …

Discrete Bethe–Sommerfeld Conjecture, Rui Han, Svetlana Jitomirskaya

Faculty Publications

In this paper, we prove a discrete version of the Bethe–Sommerfeld conjecture. Namely, we show that the spectra of multi-dimensional discrete periodic Schrödinger operators on Zd lattice with sufficiently small potentials contain at most two intervals. Moreover, the spectrum is a single interval, provided at least one of the periods is odd, and can have a gap whenever all periods are even.

Characterization Of Intersecting Families Of Maximum Size In Psl(2,Q), Ling Long, Rafael Plaza, Peter Sin, Qing Xiang

Faculty Publications

We consider the action of the 2-dimensional projective special linear group PSL(2,q) on the projective line PG(1,q) over the finite field Fq, where q is an odd prime power. A subset S of PSL(2,q) is said to be an intersecting family if for any g1,g2∈S, there exists an element x∈PG(1,q) such that xg1=xg2. It is known that the maximum size of an intersecting family in PSL(2,q) is q(q−1)/2. We prove that all intersecting families of maximum size are cosets of point stabilizers for all odd prime powers q>3.

On-Orbit Operations And Offline Data Processing Of Calet Onboard The Iss, Y. Asaoka, S. Ozawa, S. Torii, O. Adriani, Y. Akaike, K. Asano, M. G. Bagliesi, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, P. Brogi, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, A. Javaid, K. Kasahara, J. Kataoka

Faculty Publications

The CALorimetric Electron Telescope (CALET), launched for installation on the International Space Station (ISS) in August, 2015, has been accumulating scientific data since October, 2015. CALET is intended to perform long-duration observations of high-energy cosmic rays onboard the ISS. CALET directly measures the cosmic-ray electron spectrum in the energy range of 1 GeV to 20 TeV with a 2% energy resolution above 30 GeV. In addition, the instrument can measure the spectrum of gamma rays well into the TeV range, and the spectra of protons and nuclei up to a PeV. In order to operate the CALET onboard ISS, JAXA …

An Evaluation Of College Student Attitudes Toward Gay Adoption, Cassandra Chaney Phd, Le'brian Patrick

Faculty Publications

Given the increasing debate regarding same-sex marriage and same-sex adoption, few studies to date have examined college student attitudes regarding this topic. This qualitative study explores the sentiments of 31 college students from a large university in the southern region of the country towards gay adoption before and after viewing the documentary We Are Dad (2005). The study allowed students to provide their level of agreement or disagreement with the statements provided by respondents on a public blog site who debated both sides of this issue. In addition, students responded to the following two questions during two points in time: …

Large Deviation Principle For Stochastic Integrals And Stochastic Differential Equations Driven By Infinite-Dimensional Semimartingales, Arnab Ganguly

Faculty Publications

The paper concerns itself with establishing large deviation principles for a sequence of stochastic integrals and stochastic differential equations driven by general semimartingales in infinite-dimensional settings. The class of semimartingales considered is broad enough to cover Banach space-valued semimartingales and the martingale random measures. Simple usable expressions for the associated rate functions are given in this abstract setup. As illustrated through several concrete examples, the results presented here provide a new systematic approach to the study of large deviation principles for a sequence of Markov processes.

Primordial Power Spectrum From The Dapor–Liegener Model Of Loop Quantum Cosmology, Ivan Agullo

Faculty Publications

We compute the predictions for the power spectrum of scalar perturbations from a recent new proposal for the effective Hamiltonian of loop quantum cosmology. The model provides an attractive picture of the early cosmos, in which our classical Friedmann–Lemaître–Robertson–Walker universe emerges from a quantum phase where the spacetime curvature remains constant and of Planckian size. We compare the predictions for the cosmic microwave background with previous results obtained within loop quantum cosmology, and discuss the differences and similarities. The analysis provides an example of the way differences between quantization schemes can be translated to physical observables.

Bounded Backstepping Control And Robustness Analysis For Time-Varying Systems Under Converging-Input-Converging-State Conditions, Frédéric Mazenc, Michael Malisoff, Laurent Burlion, Jerome Weston

Faculty Publications

We provide new bounded backstepping results that ensure global asymptotic stability for a large class of partially linear systems with an arbitrarily large number of integrators. We use a dynamic extension that contains one artificial delay, and a converging-input-converging-state assumption. When the nonlinear subsystem is control affine, we provide sufficient conditions for our converging-input-converging-state assumption to hold. We also show input-to-state stability with respect to a large class of model uncertainties, and robustness to delays in the measurements of the state of the nonlinear subsystem. We illustrate our result in a first example that has a nondifferentiable vector field and …

Rényi Relative Entropies Of Quantum Gaussian States, Kaushik P. Seshadreesan, Ludovico Lami, Mark M. Wilde

Faculty Publications

The quantum Rényi relative entropies play a prominent role in quantum information theory, finding applications in characterizing error exponents and strong converse exponents for quantum hypothesis testing and quantum communication theory. On a different thread, quantum Gaussian states have been intensely investigated theoretically, motivated by the fact that they are more readily accessible in the laboratory than are other, more exotic quantum states. In this paper, we derive formulas for the quantum Rényi relative entropies of quantum Gaussian states. We consider both the traditional (Petz) Rényi relative entropy as well as the more recent sandwiched Rényi relative entropy, finding formulas …

Woody Plants Optimise Stomatal Behaviour Relative To Hydraulic Risk, William R.L. Anderegg, Adam Wolf, Adriana Arango-Velez, Brendan Choat, Daniel J. Chmura, Steven Jansen, Thomas Kolb, Shan Li, Frederick C. Meinzer, Pilar Pita, Víctor Resco De Dios, John S. Sperry, Brett T. Wolfe, Stephen Pacala

Faculty Publications

Stomatal response to environmental conditions forms the backbone of all ecosystem and carbon cycle models, but is largely based on empirical relationships. Evolutionary theories of stomatal behaviour are critical for guarding against prediction errors of empirical models under future climates. Longstanding theory holds that stomata maximise fitness by acting to maintain constant marginal water use efficiency over a given time horizon, but a recent evolutionary theory proposes that stomata instead maximise carbon gain minus carbon costs/risk of hydraulic damage. Using data from 34 species that span global forest biomes, we find that the recent carbon-maximisation optimisation theory is widely supported, …

Matrix And Area Effects On The Nutritional Condition Of Understory Birds In Amazonian Rainforest Fragments, Angélica Hernández-Palma, Philip C. Stouffer

Faculty Publications

Forest fragmentation, a result of deforestation, not only decreases the amount of habitat available for wildlife, but also increases the isolation of the remaining fragments and the area of edges surrounding them. Also, deforestation often leads to the creation of a dynamic regenerating matrix where cleared land is subsequently abandoned. Here we examine the effects of fragmentation and landscape change on the nutritional condition of Amazonian rainforest birds at the Biological Dynamics of Forest Fragments Project, near Manaus, Brazil. We analyzed ptilochronology-based measurements of feather growth rate in 12 species living in fragments within a dynamic landscape over 21 years. …

What Can Mixed-Species Flock Movement Tell Us About The Value Of Amazonian Secondary Forests? Insights From Spatial Behavior, Karl Mokross, Jonathan R. Potts, Cameron L. Rutt, Philip C. Stouffer

Faculty Publications

The value of secondary forest for rain forest species remains an important question for conservation in the 21st century. Here, we describe the spatial behavior of understory mixed-species flocks in a heterogeneous landscape in central Amazonia. Understory mixed-species flocks represent a diverse, highly organized component of the rich Amazonian avifauna. We recorded movements within 26 flock home ranges in primary forest, secondary forest, interfaces between forest types, and forest fragments. We describe frequency and movement orientation in relation to forest edges, movement patterns and proportion of use between secondary and primary forest, the relation between home range sizes and vegetation …

Predicting Tree Height From Tree Diameter And Dominant Height Using Mixed-Effects And Quantile Regression Models For Two Species In Turkey, Ramazan Özçelik, Quang V. Cao, Guillermo Trincado, Nilsun Göçer

Faculty Publications

Height-diameter models were developed for Brutian pine (Pinus brutia Ten.) and Taurus cedar (Cedrus libani A. Rich.) in Turkey. A modified Chapman-Richards model that includes dominant height was used to predict tree height from diameter. Using the twofold evaluation scheme, five alternative modeling approaches were evaluated: (1) fixed-effects model, (2) calibrated fixed-effects model, (3) calibrated mixed-effects model, (4) three-quantile regression method, and (5) five-quantile regression method. Parameters of fixed-effects, mixed-effects and quantile regression models were calibrated by use of a subset of height measurements, ranging from 1 to 10 sample trees per plot. Evaluation statistics show that both quantile regression …

Comparison Of Performance And Quantitative Descriptive Analysis Sensory Profiling And Its Relationship To Consumer Liking Between The Artisanal Cheese Producers Panel And The Descriptive Trained Panel, Emmanuel De Jesús Ramírez-Rivera, Pablo Díaz-Rivera, Lorena Guadalupe Ramón-Canul, José Manuel Juárez-Barrientos, Jesús Rodríguez-Miranda, Erasmo Herman-Lara, Witoon Prinyawiwatkul, José Andrés Herrera-Corredor

Faculty Publications

The aim of this research was to compare the performance and sensory profiling of a panel of artisanal cheese producers against a trained panel and their relationship to consumer liking (external preference mapping). Performance was analyzed statistically at an individual level using the Fisher's test (F) for discrimination, the mean square error for repeatability, and Manhattan plots for visualizing the intra-panel homogeneity. At group level, performance was evaluated using ANOVA. External preference mapping technique was applied to determine the efficiency of each sensory profile. Results showed that the producers panel was discriminant and repetitive with a performance similar to that …

Relative Contributions Of Halobacteriovorax And Bacteriophage To Bacterial Cell Death Under Various Environmental Conditions, Huan Chen, Edward A. Laws, Julio L. Martin, Timkhite Kulu Berhane, Paul A. Gulig, Henry N. Williams

Faculty Publications

The role of protists and bacteriophages in bacterial predation in the microbial food web has been well studied. There is mounting evidence that Bdellovibrio and like organisms (BALOs) also contribute to bacterial mortality and, in some cases, more so than bacteriophages. A full understanding of the ecologic function of the microbial food web requires recognition of all major predators and the magnitude of each predator’s contribution. Here we investigated the contribution of Halobacteriovorax, one of the BALOs, and bacteriophages when incubated with their common prey, Vibrio vulnificus, in a seawater microcosm. We observed that Halobacteriovorax was the greatest responder to …

Stabilization Of Miscible Viscous Fingering By A Step Growth Polymerization Reaction, S. Stewart, D. Marin, M. Tullier, J. Pojman, E. Meiburg, P. Bunton

Faculty Publications

© 2018, Springer-Verlag GmbH Germany, part of Springer Nature. Abstract: Fingering is a hydrodynamic instability that occurs when a more mobile fluid displaces a fluid of lower mobility. When the primary source of the mobility difference is viscosity, the instability is termed viscous fingering. Viscous fingering is often, though not always, undesirable in industrial processes, particularly secondary petroleum recovery. Linear stability analysis by Hejazi et al. has indicated that the production of a non-monotonic viscosity profile can stabilize the interface. Herein, we use step-growth polymerization at the interface between two miscible monomers as a model system. In particular, a dithiol …

Correction To: Accuracy Of Genomic Selection To Predict Maize Single-Crosses Obtained Through Different Mating Designs (Theoretical And Applied Genetics, (2018), 131, 5, (1153-1162), 10.1007/S00122-018-3068-8), Roberto Fritsche-Neto, Deniz Akdemir, Jean Luc Jannink

Faculty Publications

Unfortunately, the first author name of the above-mentioned article was incorrectly published in the original publication. The complete correct name should read as follows.

Emotional Judges And Unlucky Juveniles, Ozkan Eren, Naci Mocan

Faculty Publications

Employing the universe of juvenile court decisions in a US state between 1996 and 2012, we analyze the effects of emotional shocks associated with unexpected outcomes of football games played by a prominent college team in the state. We find that unexpected losses increase sentence lengths assigned by judges during the week following the game. Unexpected wins, or losses that were expected to be close contests ex ante have no impact. The effects of these emotional shocks are asymmetrically borne by black defendants. The impact of upset losses on sentence lengths is larger for defendants if their cases are handled …

Self-Regulation Of Emotional Responses To Zika: Spiral Of Fear, James Price Dillard, Chun Yang, Ruobing Li

Faculty Publications

Fear of infectious disease can create a variety of problems not the least of which is fear itself. An important question is how individuals attempt to manage their fear. The appearance of Zika in the U.S. presented an opportunity to examine this issue in a consequential natural context. Beginning nine days after the W.H.O. declared Zika a world health crisis, two-waves of survey data were collected from women ages 18–35 who were living in the Southern U.S. (N = 561). Most respondents (71%) used one or more emotion regulation strategies and a plurality (41%) utilized multiple strategies. Fear of Zika …

Criteria And Tools For Determining Drainage Divide Stability, Adam M. Forte, Kelin X. Whipple

Faculty Publications

© 2018 Elsevier B.V. Watersheds are the fundamental organizing units in landscapes and thus the controls on drainage divide location and mobility are an essential facet of landscape evolution. Additionally, many common topographic analyses fundamentally assume that river network topology and divide locations are largely static, allowing channel profile form to be interpreted in terms of spatio-temporal patterns of rock uplift rate relative to base level, climate, or rock properties. Recently however, it has been suggested that drainage divides are more mobile than previously thought and that divide mobility, and resulting changes in drainage area, could potentially confound interpretations of …

Robust Optimization Of Cyclic Co2 Flooding Through The Gas-Assisted Gravity Drainage Process Under Geological Uncertainties, Watheq J. Al-Mudhafar, Dandina N. Rao, Sanjay Srinivasan

Faculty Publications

The purpose of this research is to determine an estimate for actual optimal oil recovery through cyclic Gas-Assisted Gravity Drainage (GAGD) process in a heterogeneous sandstone reservoir under geological uncertainties. A robust optimization approach was adopted to determine the optimal durations of gas injection, soaking, and oil production under geological uncertainties. 100 stochastic reservoir realizations of the 3D permeability and porosity distributions were created to honor geological constraints. Ranking was applied through quantifying of reservoir oil response to select P10, P50, and, P90 that represent the overall reservoir uncertainty. A compositional reservoir flow simulation was used for the GAGD process …

Dimensions Of Diversity In U.S. Arts Participation: Race-Ethnicity, Education, Genre Origins, And Means Of Broadcast Consumption, Nile Degray Patterson

LSU Doctoral Dissertations

Dimensions of Diversity in U.S. Arts Participation uses data from the 2012 Survey of Public Participation in the Arts to investigate the following three research questions: (1) Does education’s association with visual and performing arts participation vary by race-ethnicity; (2) does visual and performing arts attendance amongst racial-ethnic groups differ depending upon a genre’s cultural roots; and (3) does education’s relationship to visual and performing arts consumption vary between traditional and non-traditional broadcast media? Major findings reveal that education has a more consistent positive association with the likelihood and diversity of visual and performing arts attendance for Whites than non-Whites. …

Endocannabinoid Metabolome Of Human Breast Milk, Adriana V. Gaitan Espinoza

LSU Doctoral Dissertations

Human breast milk (HBM) is an extremely complex yet fascinating biofluid tailored to meet an infant’s nutritional requirements for development. Amongst the nutrients present in HBM, the long-chain polyunsaturated fatty acids (LCPUFAs) are of high importance due to the pivotal role they play in infant cognitive and visual development, and growth. In addition, the LCPUFAs are precursors to endocannabinoids (EC) which are endogenous lipid mediators. EC exert metabolic responses including appetite and food intake regulation, and they have been identified to play a role in establishing the suckling response of the newborn that is needed to nurse. Thus, we aimed …

Throughput And Yield Improvement For A Continuous Discrete-Product Manufacturing System, Md Shahriar J. Hossain

LSU Doctoral Dissertations

A seam-welded steel pipe manufacturing process has mainly four distinct major design and/or operational problems dealing with buffer inventory, cutting tools, pipe sizing and inspection-rework facility. The general objective of this research is to optimally solve these four important problems to improve the throughput and yield of the system at a minimum cost.

The first problem of this research finds the optimal buffer capacity of steel strip coils to minimize the maintenance and downtime related costs. The total cost function for this coil feeding system is formulated as a constrained non-linear programming (NLP) problem which is solved with a search …

Virtual Element Methods On Meshes With Small Edges Or Faces, Susanne C. Brenner, Li Yeng Sung

Faculty Publications

We consider a model Poisson problem in Rd (d = 2, 3) and establish error estimates for virtual element methods on polygonal or polyhedral meshes that can contain small edges (d = 2) or small faces (d = 3). Our results extend the ones in [L. Beirão da Veiga, C. Lovadina and A. Russo, Stability analysis for the virtual element method, Math. Models Methods Appl. Sci. 27 (2017) 2557-2594] for the original two-dimensional virtual element method from [L. Beirão da Veiga, F. Brezzi, A. Cangiani, G. Manzini, L. D. Marini and A. Russo, Basic principles of virtual element methods, Math. …

Exploring The Role Of Rna Polymerase Iii Complex Assembly On Ribosomal Dna Silencing In Saccharomyces Cerevisiae, Kyle Thomas Kern

LSU Doctoral Dissertations

The yeast rDNA region is host to a number of transcriptional regulatory elements, which work in conjunction to generate essential RNA subunits of ribosomes, as well as protecting the region from DNA damage. The role of RNA polymerase III complex binding at the 5S gene on rDNA silencing in the NTS2 region was investigated, both by use of a TY1:MET15 reporter insert and a MET15 gene integration at an endogenous SphI site. It was discovered that Pol III complexes do have an effect on reporter expression in the NTS2 region, though the specific effect was different based on the method …

Numerical Convergence Of Nonlinear Nonlocal Continuum Models To Local Elastodynamics, Prashant K. Jha, Robert Lipton

Faculty Publications

We quantify the numerical error and modeling error associated with replacing a nonlinear nonlocal bond-based peridynamic model with a local elasticity model or a linearized peridynamic model away from the fracture set. The nonlocal model treated here is characterized by a double-well potential and is a smooth version of the peridynamic model introduced in the work of Silling. The nonlinear peridynamic evolutions are shown to converge to the solution of linear elastodynamics at a rate linear with respect to the length scale ε of nonlocal interaction. This rate also holds for the convergence of solutions of the linearized peridynamic model …

The Use Of Expansions To Increase The Mean Length Utterance Of Preschool Students, Kaitlyn Carley Geffen

LSU Master's Theses

Language is an important area of development addressed in preschool, as it is the foundation for literacy development and the way children express their thoughts and understandings. Mean length utterance (MLU) can be used as a measure of a child’s expressive language development. One intervention that has been used to increase MLU is expansion. Expansion is when an adult responds to a child’s utterance by expanding their sentence to form a more complete or complex sentence. This study used an Expansion Intervention to increase the MLU of preschool aged students. The subjects consisted of three preschool children attending a …

Non-Local Methods In Fracture Dynamics, Eyad Said

LSU Doctoral Dissertations

We first introduce a regularized model for free fracture propagation based on non-local potentials. We work within the small deformation setting and the model is developed within a state based peridynamic formulation. At each instant of the evolution we identify the softening zone where strains lie above the strength of the material. We show that deformation discontinuities associated with flaws larger than the length scale of non-locality $\delta$ can become unstable and grow. An explicit inequality is found that shows that the volume of the softening zone goes to zero linearly with the length scale of non-local interaction. This scaling …