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Full-Text Articles in Physical Sciences and Mathematics

Automated Negotiation Among Web Services, Khayyam Hashmi Jan 2016

Automated Negotiation Among Web Services, Khayyam Hashmi

Wayne State University Dissertations

Software as a service is well accepted software deployment and distribution model that is grown exponentially in the last few years. One of the biggest benefits of SaaS is the automated composition of these services in a composite system. It allows users to automatically find and bind these services, as to maximize the productivity of their composed systems, meeting both functional and non-functional requirements. In this paper we present a framework for modeling the dependency relationship of different Quality of Service parameters of a component service. Our proposed approach considers the different invocation patterns of component services in the system …


Principal Component Analysis-Based Anatomical Motion Models For Use In Adaptive Radiation Therapy Of Head And Neck Cancer Patients, Mikhail Aleksandrovich Chetvertkov Jan 2016

Principal Component Analysis-Based Anatomical Motion Models For Use In Adaptive Radiation Therapy Of Head And Neck Cancer Patients, Mikhail Aleksandrovich Chetvertkov

Wayne State University Dissertations

Purpose: To develop standard and regularized principal component analysis (PCA) models of anatomical changes from daily cone beam CTs (CBCTs) of head and neck (H&N) patients, assess their potential use in adaptive radiation therapy (ART), and to extract quantitative information for treatment response assessment.

Methods: Planning CT (pCT) images of H&N patients were artificially deformed to create “digital phantom” images, which modeled systematic anatomical changes during Radiation Therapy (RT). Artificial deformations closely mirrored patients’ actual deformations, and were interpolated to generate 35 synthetic CBCTs, representing evolving anatomy over 35 fractions. Deformation vector fields (DVFs) were acquired between pCT and synthetic …


Development Of Gamma-Modified Atp Analogs To Study Kinase-Catalyzed Phosphorylations, Ahmed Eid Fouda Jan 2016

Development Of Gamma-Modified Atp Analogs To Study Kinase-Catalyzed Phosphorylations, Ahmed Eid Fouda

Wayne State University Dissertations

Kinase-catalyzed protein phosphorylation is one of the most important post-translational modifications that controls cascades of biochemical reactions. Irregularities in phosphorylation result in many diseases, such as diabetes mellitus, Parkinsons, and cancer. The development of new methods to monitor kinase-catalyzed phosphorylation is needed to decipher details of normal and diseased cell signaling. The Pflum lab recently developed several -modified ATP analogs to study kinase catalyzed phosphorylation reactions. The -modified ATP analogs have different tags, such as biotin for substrate labeling or aryl-azide for kinase substrates identification. Unfortunately, use of -modified ATP analogs was limited to in vitro studies due to the …


Nonlinear Stochastic Systems And Controls: Lotka-Volterra Type Models, Permanence And Extinction, Optimal Harvesting Strategies, And Numerical Methods For Systems Under Partial Observations, Ky Quan Tran Jan 2016

Nonlinear Stochastic Systems And Controls: Lotka-Volterra Type Models, Permanence And Extinction, Optimal Harvesting Strategies, And Numerical Methods For Systems Under Partial Observations, Ky Quan Tran

Wayne State University Dissertations

This dissertation focuses on a class of stochastic models formulated using stochastic differential equations with regime switching represented by a continuous-time Markov chain, which also known as hybrid switching diffusion processes. Our motivations for studying such processes in this dissertation stem from emerging and existing applications in biological systems, ecosystems, financial engineering, modeling, analysis, and control and optimization of stochastic systems under the influence of random environments, with complete observations or partial observations.

The first part is concerned with Lotka-Volterra models with white noise and regime switching represented by a continuous-time Markov chain. Different from the existing literature, the Markov …


Molecular Regulation Of Trophoblast Survival During Placentation And Pathologies Of Placental Insufficiency, Chandni V. Jain Jan 2016

Molecular Regulation Of Trophoblast Survival During Placentation And Pathologies Of Placental Insufficiency, Chandni V. Jain

Wayne State University Dissertations

HBEGF, is present in the uterus at the time of embryo implantation and protects first

trimester TB cells from apoptosis and promotes their invasion. The hypertensive disease, PE, in

which TB invasion of the uterine arteries is reduced and TB apoptosis is elevated, is

characterized by a reduction in HBEGF expression. In this study using a first trimester cell line

and villous explant culture key components involved in HBEGF survival signaling pathway were

identified. Specific MMP inhibitors established the requirement for MMP2 in HBEGF shedding

and upregulation. NGS identified a HIF regulated gene, HSPA6 (HSP70B’) and using specific

inhibitors it …


Improving User Experience In Information Retrieval Using Semantic Web And Other Technologies, Erfan Najmi Jan 2016

Improving User Experience In Information Retrieval Using Semantic Web And Other Technologies, Erfan Najmi

Wayne State University Dissertations

The need to find, access and extract information has been the motivation for many

different fields of research in the past few years. The fields such as Machine Learning,

Question Answering Systems, Semantic Web, etc. each tries to cover parts of the

mentioned problem. Each of these fields have introduced many different tools and

approaches which in many cases are multi-disciplinary, covering more than one of

these fields to provide solution for one or more of them. On the other hand, the

expansion of the Web with Web 2.0, gave researchers many new tools to extend

approaches to help users …


Novel Approaches For Assessment Of Copper Toxicity: Fast Scan Cyclic Voltammetry And Optical Bioassays, Annette R. Tremonti Jan 2016

Novel Approaches For Assessment Of Copper Toxicity: Fast Scan Cyclic Voltammetry And Optical Bioassays, Annette R. Tremonti

Wayne State University Dissertations

Anthropogenic activities negatively impact fresh water ecosystems through toxic contaminants that are released into the environment. Copper (Cu) is a water contaminant that is fundamentally persistent once introduced into the environment that has the potential for bioaccumulation. Although Cu toxicity has been studied for decades, there is still a continuing problem with new sources and pathways. New approaches are needed to understand distribution and transport of Cu and its potential for complex biological impacts beyond the simple assessment of lethality. Several novel approaches were used in this research project to advance our understanding of Cu toxicity, including fast scan cyclic …


System Support For Energy Efficient Mobile Computing, Youhuizi Li Jan 2016

System Support For Energy Efficient Mobile Computing, Youhuizi Li

Wayne State University Dissertations

Mobile devices are developed rapidly and they have been an integrated part of our daily life. With the blooming of Internet of Things, mobile computing will become more and more important. However, the battery drain problem is a critical issue that hurts user experience. High performance devices require more power support, while the battery capacity only increases 5% per year on average. Researchers are working on kinds of energy saving approaches. For examples, hardware components provide different power state to save idle power; operating systems provide power management APIs to better control power dissipation. However, the system energy efficiency is …


Essays On Oil Price Volatility And Irreversible Investment, Daniel Joseph Pastor Jan 2016

Essays On Oil Price Volatility And Irreversible Investment, Daniel Joseph Pastor

Wayne State University Dissertations

In chapter 1, we provide an extensive and systematic evaluation of the relative

forecasting performance of several models for the volatility of daily spot

crude oil prices. Empirical research over the past decades has uncovered

significant gains in forecasting performance of Markov Switching GARCH

models over GARCH models for the volatility of financial assets and crude

oil futures. We find that, for spot oil price returns, non-switching models

perform better in the short run, whereas switching models tend to do better

at longer horizons.

In chapter 2, I investigate the impact of volatility on firms' irreversible investment decisions using real …


Sharing-Aware Resource Management Algorithms For Virtual Computing Environments, Safraz Rampersaud Jan 2016

Sharing-Aware Resource Management Algorithms For Virtual Computing Environments, Safraz Rampersaud

Wayne State University Dissertations

Virtualization technologies in cloud computing are ubiquitous throughout data centers around the world where providers consider operational costs and fast delivery guarantees for a variety of profitable services. These providers should consistently invoke measures for increasing the efficiencies of their virtualized services in a competitive environment where fast entry to market, technology advancement, and service price differentials separate sustaining providers from antiquated ones. Therefore, providers seeking further efficiencies and profit opportunities should consider how their resources are managed in virtual computing environments which leverage memory reclamation techniques, specifically page-sharing; motivating the design of new memory sharing-aware resource management algorithms. In …


Enhanced Pump Schedule Optimization For Large Water Distribution Networks To Maximize Environmental And Economic Benefits, Seyed Mohsen Sadatiyan Abkenar Jan 2016

Enhanced Pump Schedule Optimization For Large Water Distribution Networks To Maximize Environmental And Economic Benefits, Seyed Mohsen Sadatiyan Abkenar

Wayne State University Dissertations

For more than four decades researchers tried to develop optimization method and tools to reduce electricity consumption of pump stations of water distribution systems. Based on this ongoing research trend, about a decade ago, some commercial pump operation optimization software introduced to the market. Using metaheuristic and evolutionary techniques (e.g. Genetic Algorithm) make some commercial and research tools able to optimize the electricity cost of small water distribution systems (WDS). Still reducing the environmental footprint of these systems and dealing with large and complicated water distribution system is a challenge.

In this study, we aimed to develop a multiobjective optimization …


Cohomology Operations On Random Spaces, Matthew John Zabka Jan 2016

Cohomology Operations On Random Spaces, Matthew John Zabka

Wayne State University Dissertations

Topology has recently received more attention from statisticians as some its tools have been applied to understanding the shape of data. In particular, a data set can generate a topological space, and this space’s topological structure can give us insight into some properties of the data. This framework has made it necessary to study random spaces generated by data. For example, without an understanding of the probabilistic properties of random spaces, one cannot conclude with any degree of confidence what the tools of topology tell us about a data set. While some results are known about the cohomological structure of …


Design Of First-Row Transition Metal Bis(Alkoxide) Complexes And Their Reactivity Toward Nitrene And Carbene Transfer, James Bellow Jan 2016

Design Of First-Row Transition Metal Bis(Alkoxide) Complexes And Their Reactivity Toward Nitrene And Carbene Transfer, James Bellow

Wayne State University Dissertations

The novel alkoxide ligand [OCtBu2Ph], or [OR], was synthesized in a single step as a lithium salt. It was then reacted with a series of first-row transition metal(II) halides, with widely varying results. Upon reaction with chromium, manganese, iron, or cobalt(II) chloride, dimeric complexes of the form M2(OR)4Li2Cl2 were formed, which displayed rare seesaw geometry at the metal. This unusual geometry was confirmed by various spectroscopic and computational studies. Computational studies also indicate that the steric bulk of the ligand, as well as the inclusion of lithium atoms in the molecules, are what lead to the seesaw geometry. Reaction of …


Europium(Ii)-Containing Complexes For Responsive Magnetic Resonance Imaging, Levi Alexander Ekanger Jan 2016

Europium(Ii)-Containing Complexes For Responsive Magnetic Resonance Imaging, Levi Alexander Ekanger

Wayne State University Dissertations

The research projects described in this dissertation are focused on studying the oxidation of EuII-containing complexes within the context of responsive MRI. Prior to this research, EuII had not been explored within the context of oxidation-responsive MRI nor had the use of this ion been reported in vivo. The results of these studies enable predictions about the oxidation-responsive behavior of EuII-containing complexes in vitro and in vivo.

The EuII-containing cryptate 1.33 was used to evaluate EuII-based positive contrast enhancement after intravenous, intraperitoneal, and subcutaneous injections. The transitory behavior of the positive contrast enhancement correlated with reported levels of oxygenation and …


The Impact Of Multiple Imputation On The Type Ii Error Rate Of The T Test, Tammy A. Grace Jan 2016

The Impact Of Multiple Imputation On The Type Ii Error Rate Of The T Test, Tammy A. Grace

Wayne State University Dissertations

ABSTRACT

THE IMPACT OF MULTIPLE IMPUTATION ON THE TYPE II ERROR RATE OF

THE T TEST

by

TAMMY A. GRACE

August 2016

Advisor: Shlomo Sawilowsky, PhD

Major: Evaluation and Research

Degree: Doctor of Philosophy

The National Academy of Science identified numerous high priority areas for missing data research. This study addresses several of those areas by systematically investigating the impact of multiple imputation on the rejection rate of the independent samples t test under varying conditions of sample size, effect size, fraction of missing data, distribution shape, and alpha. In addition to addressing gaps in the missing data literature, this …


Dielectric Anomalies Of Both Chiral And Achiral Nematogens Near The Isotropic To Mesogenic Phase Transition, Garrett Justin Godfrey Jan 2016

Dielectric Anomalies Of Both Chiral And Achiral Nematogens Near The Isotropic To Mesogenic Phase Transition, Garrett Justin Godfrey

Wayne State University Dissertations

The dielectric properties of nematic liquid crystals were studied in both the achiral and chiral limits. For achiral nematics, the literature documents that pretransitional curvature occurs for polar molecules on both sides of the nematic and isotropic phase transition. This curvature is due to anti-parallel dimer formation. However, past models have failed to quantitatively describe pretransitional curvature. Through a generalization of the order parameter, a macroscopic model has been developed to mathematically describe the pretransitional curvature on the isotropic side of the transition. The new model was fitted to dielectric data from the literature. Meaningful parameter estimates were extracted.

The …


Big Data Management Using Scientific Workflows, Andrii Kashliev Jan 2016

Big Data Management Using Scientific Workflows, Andrii Kashliev

Wayne State University Dissertations

Humanity is rapidly approaching a new era, where every sphere of activity will be informed by the ever-increasing amount of data. Making use of big data has the potential to improve numerous avenues of human activity, including scientific research, healthcare, energy, education, transportation, environmental science, and urban planning, just to name a few. However, making such progress requires managing terabytes and even petabytes of data, generated by billions of devices, products, and events, often in real time, in different protocols, formats and types. The volume, velocity, and variety of big data, known as the "3 Vs", present formidable challenges, unmet …


Novel Regression Models For High-Dimensional Survival Analysis, Yan Li Jan 2016

Novel Regression Models For High-Dimensional Survival Analysis, Yan Li

Wayne State University Dissertations

Survival analysis aims to predict the occurrence of specific events of interest at future time points. The presence of incomplete observations due to censoring brings unique challenges in this domain and differentiates survival analysis techniques from other standard regression methods. In this thesis, we propose four models to deal with the high-dimensional survival analysis. Firstly, we propose a regularized linear regression model with weighted least-squares to handle the survival prediction in the presence of censored instances. We employ the elastic net penalty term for inducing sparsity into the linear model to effectively handle high-dimensional data. As opposed to the existing …


Synthesis Of Apramycin And Paromomycin Derivatives As Potential Next Generation Aminoglycoside Antibiotics And Chemistry Of Isothiocyanato Sialyl Donors, Appi Reddy Mandhapati Jan 2016

Synthesis Of Apramycin And Paromomycin Derivatives As Potential Next Generation Aminoglycoside Antibiotics And Chemistry Of Isothiocyanato Sialyl Donors, Appi Reddy Mandhapati

Wayne State University Dissertations

AGAs are clinically important antibacterials for human therapy and have long been used as highly potent antibiotics for treating several bacterial infections. The fidelity of protein synthesis is affected by AGAs in the course of binding to specific sites of the bacterial rRNA. The clinical use of AGAs and their applications as therapeutics is restricted by toxicity (irreversible ototoxicity and reversible nephrotoxicity) and by the resistance of pathogens. The objective of this research was the development of proficient AGAs that are less toxic (i.e., more selective) and that evade resistance. The first three chapters of this thesis are aimed towards …


Variational Analysis And Stability In Optimization, M. Ebrahim Sarabi Jan 2016

Variational Analysis And Stability In Optimization, M. Ebrahim Sarabi

Wayne State University Dissertations

The dissertation is devoted to the study of the so-called full Lipschitzian stability of local solutions to finite-dimensional parameterized problems of constrained optimization, which has been well recognized as a very important property from both viewpoints of optimization theory and its applications. Employing second-order subdifferentials of variational analysis, we obtain necessary and sufficient conditions for fully stable local minimizers in general classes of constrained optimization problems including problems of composite optimization as well as problems of nonlinear programming with twice continuously differentiable data. Based on our recent explicit calculations of the second-order subdifferential for convex piecewise linear functions, we establish …


Nano-Structured Electrocatalysts For High Performance Lithium Sulfur Batteries, Negar Mosavati Jan 2016

Nano-Structured Electrocatalysts For High Performance Lithium Sulfur Batteries, Negar Mosavati

Wayne State University Dissertations

Ni nanoparticles has been investigated as a carbon-free cathode material for dissolved polysulfide Li-S battery. A series of Ni nanoparticles with nominal particle size of 20, 40, and 100 nm have been used as electrocatalysts, and the effect of particle size on Li-S battery performance has been investigated. In addition, graphene has been chosen as a support to anchor the Ni nanoparticles, and the synergetic effect of carbon material and Ni nanoparticles on Li-S battery electrochemical performance has been studied. The results indicated there is a strong particle size effect. Ni/graphene electrode exhibits a capacity of 753 mAh g-1 sulfur …


Synthesis And Heteroallene Reactivity Of Bis(Aldimino)Pyridine Nickel Complexes In Four Different Oxidation States, Blake Reed Jan 2016

Synthesis And Heteroallene Reactivity Of Bis(Aldimino)Pyridine Nickel Complexes In Four Different Oxidation States, Blake Reed

Wayne State University Dissertations

A series of redox non-innocent bis(aldimino)pyridine ligands were synthesized. These were then reacted with nickel(II) salts to form Ni[NNN]X2 complexes. Cyclic voltammograms of these nickel(II) complexes suggest that more reduced states can be achieved. Reduction of these nickel(II) complexes lead to distorted square planar complexes with the halide bent ~20° out of the plane. EPR suggests that spin density is located on the metal as g-values of >2.01 were obtained. This differs from previously reported analogous bis(ketimino)pyridine complexes, which show a ligand-based radical and nickel(II). DFT confirms that as the Npyr-Ni-X angle decreases, spin density on the nickel increases. Because …


How Geometric Distortions Scatter Electronic Excitations In Conjugated Macromolecules: Towards Photoinduced Relaxation And Energy Transfer, Tian Shi Jan 2016

How Geometric Distortions Scatter Electronic Excitations In Conjugated Macromolecules: Towards Photoinduced Relaxation And Energy Transfer, Tian Shi

Wayne State University Dissertations

The exciton scattering (ES) approach has been developed to study electronic excitations in large branched conjugated molecules. It attributes excited states to standing waves in the quasi-one-dimensional system by assuming a quasi-particle picture of optical excitations. Tight binding models extend capability of the ES approach to investigate the exciton-phonon coupling.

The topological counting method plays a substantial role in constructing tight binding models. It depicts the ES equations as a topological intersection problem. Then, by applying the index theorem, we can get the total number of excited states, which is equal to the number of repeat units plus topological charges …


Electronic Transport In Two-Dimensional Systems In The Quantum Hall Regime, Vinicio Tarquini Jan 2016

Electronic Transport In Two-Dimensional Systems In The Quantum Hall Regime, Vinicio Tarquini

Wayne State University Dissertations

The integer and the fractional quantum Hall effects are essential to the exploration of quantum matters characterized by topological phases. A quantum Hall system hosts one-dimensional (1D) chiral edge channels that manifest zero magnetoresistance, dissipationless due to the broken time reversal symmetry, and quantized Hall resistance v h e^2 with v being the topological invariant (or Chern number). The 1-1 correspondence between the conducting gapless edge channels to the gapped incompressible bulk states is a defining character of a topological insulator (TI). Understanding this correspondence in real systems, especially the origin of its robustness (in terms of the limit of …


Substrate Effects And Dielectric Integration In 2d Electronics, Bhim Prasad Chamlagain Jan 2016

Substrate Effects And Dielectric Integration In 2d Electronics, Bhim Prasad Chamlagain

Wayne State University Dissertations

The ultra-thin body of monolayer (and few-layer) two dimensional (2D) semiconducting materials such as transitional metal dichalconiges (TMDs), black phosphorous (BP) has demonstrated tremendous beneficial physical, transport, and optical properties for a wide range of applications. Because of their ultrathin bodies, the properties of 2D materials are highly sensitive to environmental effects. Particularly, the performance of 2D semiconductor electronic devices is strongly dependent on the substrate/dielectric properties, extrinsic impurities and absorbates. In this work, we systematically studied the transport properties of mechanically exfoliated few layer TMD field-effect transistors (FETs) consistently fabricated on various substrates including SiO2,Parylene –C, Al2O3, SiO2 modified …


Identification Of Lead-Sensitive Expression And Splicing Quantitative Trait Loci In Drosophila Melanogaster By Analysis Of Rna-Seq Data, Wen Qu Jan 2016

Identification Of Lead-Sensitive Expression And Splicing Quantitative Trait Loci In Drosophila Melanogaster By Analysis Of Rna-Seq Data, Wen Qu

Wayne State University Dissertations

Lead exposure has long been one of the most important topics in global public health since it is a potent developmental neurotoxin. Here, we conducted an expression QTL (eQTLs) analysis, which is genome-wide association analysis of genetic variants with differential gene expression, in the male heads of 79 Drosophila melanogaster recombinant inbred lines originally from eight parental strains in the presence or absence of developmental exposure to 250 µM lead acetate. The aim was to study the effects of lead exposure on gene expression and identify the lead-responsive genes. After detecting 1,536 cis-eQTLs and 952 trans-eQTLs (1000 permutation threshold at …


Synthesis And Characterization Of Transition Metal Phosphide Nanoparticles For Catalytic Applications: Model Catalysts For Hydrodesulfurization And Electrocatalysts For The Oxygen Evolution Reaction, Don Malinda Ruchira Liyanage Jan 2016

Synthesis And Characterization Of Transition Metal Phosphide Nanoparticles For Catalytic Applications: Model Catalysts For Hydrodesulfurization And Electrocatalysts For The Oxygen Evolution Reaction, Don Malinda Ruchira Liyanage

Wayne State University Dissertations

Transition metal phosphides are emerging as efficient catalysts for different processes. Although binary phases have been extensively studied recently researchers have explored the synergism afforded by bimetallic ternary transition metal phosphides. The conventional catalyst preparation methods (temperature programmed reduction or solvothermal synthesis) yield inhomogeneous samples, preventing a detailed understanding of how active site density impacts catalytic activity and mechanism. In contrast, solution-phase arrested-precipitation reactions produce uniform nanoparticles with an excellent control on size, morphology and composition.

This dissertation describes the synthesis of ternary transition metal phosphide nanoparticles (Ni2-xCoxP and Ni2-xRuxP) by solution-phase arrested-precipitation reactions and evaluation of their composition-dependent catalytic …


An Automated System To Measure The Quantum Efficiency Of Ccds For Astronomy, Rebecca Ann Coles Jan 2016

An Automated System To Measure The Quantum Efficiency Of Ccds For Astronomy, Rebecca Ann Coles

Wayne State University Dissertations

We describe a system to measure the Quantum Efficiency in the wavelength range of 300nm to 1100nm of 40x40 mm n-channel CCD sensors for the construction of the 3.2 gigapixel LSST focal plane. The technique uses a series of instruments to create a very uniform flux of photons of controllable intensity in the wavelength range of interest across the face the sensor. This allows the absolute Quantum Efficiency to be measured with an accuracy in the 1% range. This system will be part of a production facility at Brookhaven National Lab for the basic component of the LSST camera.


Use Of 17o-Nmr Spectroscopy To Study The Coordination Chemistry Of Trivalent Lanthanide Ions In Solution, Zhijin Lin Jan 2016

Use Of 17o-Nmr Spectroscopy To Study The Coordination Chemistry Of Trivalent Lanthanide Ions In Solution, Zhijin Lin

Wayne State University Dissertations

Trivalent lanthanide (Ln3+)-containing complexes have a number of important applications in molecular imaging, catalysis, medical diagnosis, information storage, and environmental sensing. The properties of Ln3+-containing complexes that are useful for these applications are influenced by coordination chemistry, including the number of coordinated ligands and ligand-exchange rates. The coordination numbers for water molecules bound to Eu3+ and Tb3+ have been studied by luminescence-decay measurements; however, the coordination numbers of other important oxygen-containing functional groups such as ketones, esters, ethers, sulfonyls, amides, phosphine oxides, and aldehydes have not been as thoroughly studied in solution because of the lack of hydroxyl groups that …


User-Centric Power Management For Mobile Operating Systems, Hui Chen Jan 2016

User-Centric Power Management For Mobile Operating Systems, Hui Chen

Wayne State University Dissertations

The power consumption of mobile devices must be carefully managed to provide a satisfied battery life to users. This target, however, recently has become more and more difficult to complete. We still cannot expect the battery life problem be solved economically shortly, even though researchers already addressed many aspects of this problem. Principally, that's because existing power management systems, which concentrate on controlling hardware power states, cannot effectively make these hardware components work in low-power mode. Why is this the case?

Based on our analysis of 14 users' device usage trace, we found that background applications generate too many activities …