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Theses/Dissertations

2011

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Full-Text Articles in Physical Sciences and Mathematics

Synthesis And Biological Evaluation Of Aeruginosin Based Compounds And Self-Assembly Of Glucosamine Based Compounds, Navneet Goyal Dec 2011

Synthesis And Biological Evaluation Of Aeruginosin Based Compounds And Self-Assembly Of Glucosamine Based Compounds, Navneet Goyal

University of New Orleans Theses and Dissertations

Aeruginosins are a family of marine natural products containing mostly non-proteogenic amino acids. These compounds contain a common 2-carboxy-6-hydroxy-octaindole (Choi) rigid bicyclic structure. Many aeruginosins are inhibitors for enzymes involved in the blood coagulation cascade, such as thrombin and Factor VIIa. In order to understand the structure activity relationship (SAR) of the aeruginosins and to discover novel anticoagulants with potentially improved inhibitory and pharmacokinetic properties, in the first part of my thesis I have discussed, synthesis of a series of novel analogs of aeruginosin 298-A, in which the Choi will be replaced with L-proline and oxygenated Choi analogs, and the …


Android Memory Capture And Applications For Security And Privacy, Joseph T. Sylve Dec 2011

Android Memory Capture And Applications For Security And Privacy, Joseph T. Sylve

University of New Orleans Theses and Dissertations

The Android operating system is quickly becoming the most popular platform for mobiledevices. As Android’s use increases, so does the need for both forensic and privacy toolsdesigned for the platform. This thesis presents the first methodology and toolset for acquiringfull physical memory images from Android devices, a proposed methodology for forensicallysecuring both volatile and non-volatile storage, and details of a vulnerability discovered by theauthor that allows the bypass of the Android security model and enables applications to acquirearbitrary permissions.


Investigating The Thermal Stability And Cation Ordering In Layered Cathode Lixmo2 (X ≤ 1; M = Co, Mn, Ni) Materials For Li-Ion Rechargeable Batteries And Studying The Ferroelectric Properties Of Linbo3 Nanoparticles, Debasish Mohanty Dec 2011

Investigating The Thermal Stability And Cation Ordering In Layered Cathode Lixmo2 (X ≤ 1; M = Co, Mn, Ni) Materials For Li-Ion Rechargeable Batteries And Studying The Ferroelectric Properties Of Linbo3 Nanoparticles, Debasish Mohanty

University of New Orleans Theses and Dissertations

In recent years, transition metal oxides have drawn extensive attention because of their wide application in electronic, memory, battery, informatics, and optoelectronics devices. In this dissertation, we have studied two different types of oxide materials which are technologically important: LiMO 2 (M = Co, Mn, Ni), has served as cathode materials in the rechargeable battery, and LiNbO3, has wide application in ferroelectric devices such as electronics, non-volatile memories, and thin film capacitors. LiMO2 was synthesized and characterized to understand the correlation between capacity fading and thermal stability relating to the microstructures. Our results showed that delithiated (charged) LiCoO2, forms a …


Synthesis And Applications Of Luminescent Quantum Dots In Bioassays, Venkata Ramana Kethineedi Dec 2011

Synthesis And Applications Of Luminescent Quantum Dots In Bioassays, Venkata Ramana Kethineedi

University of New Orleans Theses and Dissertations

Luminescent quantum dot (QD) based probes have gained significance in the last decade for optical imaging of cells, tissues and in bioassays as alternatives to conventional organic fluorophores. The main objective of my PhD dissertation was to develop luminescent quantum dot based bioassays for real time monitoring of enzyme activity and simultaneous detection of several biomarkers. The quantum dot based bioassays developed will be potential tools in identification and diagnosis of several ailments that interfere with normal living conditions of human beings.

In Chapter 2 new liposome encapsulated quantum dot based fluorescence resonance energy transfer (FRET) probes have been fabricated …


Synthesis And Antifungal Evaluation Of Spirostane Saponins, Sunil Upadhyay Dec 2011

Synthesis And Antifungal Evaluation Of Spirostane Saponins, Sunil Upadhyay

University of New Orleans Theses and Dissertations

Methods for the preparation of novel antifungal saponins have been investigated in

order to further explore their medicinal utility and provide the opportunity to synthesize

their derivatives.

Through this work, several partially protected stereoisomers of Cholestane,

Androstane and Spirostane have been prepared which could be used for the synthesis of

various saponin derivatives in order to discover novel saponin based antifungal agent.

Various mono and disaccharide derivatives of these steroids have been synthesized and

evaluated for their antifungal activity against four pathogenic fungal strains. Among the

various derivatives maltose derivatives were found to have the best antifungal activity.

However there …


Influence Of Weak Interactions On Supramolecular Binding: Characterization Of Cucurbituril Complexes With Alkylmonoammonium Ions Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Ruijan Shi Dec 2011

Influence Of Weak Interactions On Supramolecular Binding: Characterization Of Cucurbituril Complexes With Alkylmonoammonium Ions Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Ruijan Shi

Theses and Dissertations

This thesis focuses on using mass spectrometry-based techniques for characterizing the structure and behavior of cucurbituril complexes in the gas phase. Both solvent and counter ion effects can be completely eliminated in the gas phase and the intrinsic interactions in the system are directly shown in the experimental results. Chapter 1 introduces the structures, properties and host-guest chemistry of cucurbituril, and FTICR mass spectrometry including instrumentation, performance and working principles. Two mass spectrometry-based methods for supramolecular characterization, sustained off-resonance irradiation collision induced dissociation (SORI CID) and ion molecule equilibrium measurements, are also discussed in this chapter. Chapter 2 characterizes the …


Study Of The Vaporization Enthalpies By Correlation-Gas Chromatography, Dmitry Lipkind Dec 2011

Study Of The Vaporization Enthalpies By Correlation-Gas Chromatography, Dmitry Lipkind

Dissertations

The focus of this thesis is on the measurement and collection of thermodynamic and physical property data, including vaporization, fusion, and sublimation enthalpies and vapor pressures of large n-alkanes, nitrogen heterocycles and related compounds by a technique developed in our laboratory referred to as correlation-gas chromatography (C-GC). These thermodynamic data are of importance to several disciplines that include chemical engineering, as well as the pharmaceutical and the petrochemical industries. Vapor pressures of large hydrocarbons are fundamental data required in the petroleum industry to develop thermodynamic models for dealing with crude oil. Environmental chemists and engineers use vapor pressures and vaporization …


The Vulnerability Assessment And Penetration Testing Of Two Networks, Steven L. Simpson Dec 2011

The Vulnerability Assessment And Penetration Testing Of Two Networks, Steven L. Simpson

Regis University Student Publications (comprehensive collection)

Vulnerability assessments and penetration testing are two approaches available for use by internet security practitioners to determine the security posture of information networks. By assessing network vulnerabilities and attempting to exploit found vulnerabilities through penetration testing security professionals are able to evaluate the effectiveness of their network defenses by identifying defense weaknesses, affirming the defense mechanisms in place, or some combination of the two. This project is a discussion of the methods and tools used during the vulnerability assessment and penetration testing, and the respective test results of two varied and unique networks. The assessment and testing of the first …


Molecular Dynamics Studies Of Interactions Of Phospholipid Membranes With Dehydroergosterol And Penetrating Peptides, Amir Mohsen Pourmousa Abkenar Dec 2011

Molecular Dynamics Studies Of Interactions Of Phospholipid Membranes With Dehydroergosterol And Penetrating Peptides, Amir Mohsen Pourmousa Abkenar

Electronic Thesis and Dissertation Repository

We have performed molecular modeling of membrane and peptide systems by employing the classical molecular dynamics method and force field parameterizations. In this thesis, our main interest is the interaction of sterols as well as peptides with membranes. The thesis consists of three related projects. The first project focuses on cholesterol (CHOL) and dehydroergosterol (DHE) interacting with palmitoyl-oleoyl phosphatidylcholine (POPC) lipid bilayers. We study the effects of both sterols on the bilayer and compare them with each other. We first study the condensing and ordering effect of these sterols. Then, we study their orientations within the bilayer and relate them …


Lesson Not Learned: Deepwater Horizon Research And Media Coverage Exposes Gaps In Knowledge And Risky Protocol Within The Oil Industry, Lauren Haller Dec 2011

Lesson Not Learned: Deepwater Horizon Research And Media Coverage Exposes Gaps In Knowledge And Risky Protocol Within The Oil Industry, Lauren Haller

Honors Theses

An insatiable thirst for oil has led poorly coordinated, risk-prone megasystems deeper into the ocean in search of new oil reserves. Profit-driven agendas at the corporate level have a top-down effect within these megasystems. Cost-cutting and risk-downplaying leaves the field employees unprepared to handle emergencies. A series of costly mistakes led to the 2010 BP Deepwater Horizon oil spill, which caused extensive damage to an already fragile ecosystem in the Gulf of Mexico. The wealth and political influence of the oil industry overpowers lax regulatory agencies and legislation-even though media and research has exposed frustrating parallels between the Deepwater Horizon …


Photocatalytic Activity Of Zinc Oxide Thin Films Prepared By Dc Sputter Deposition And Thermal Oxidation, Robert Louder Dec 2011

Photocatalytic Activity Of Zinc Oxide Thin Films Prepared By Dc Sputter Deposition And Thermal Oxidation, Robert Louder

Honors Theses

Zinc oxide (ZnO) is a wide-bandgap semiconductor with a broad range of applications, such as photocatalysis. The photocatalytic properties of ZnO result from the highly oxidizing holes and reducing electrons that are induced on the ZnO surface by ultraviolet (UV) light. The efficiency of electron-hole pair formation is therefore critical for photocatalysis, and thus the optical quality of the films in the UV region is of critical importance. ZnO thin films have been fabricated using DC sputter deposition of Zn-metal films followed by thermal oxidation at different temperatures (300, 600, and 900°C). Characterization of the optical properties of the resulting …


Mechanism Of G Protein Beta-Gamma Assembly Mediated By Phosducin-Like Protein 1, Chun Wan Jeffrey Lai Dec 2011

Mechanism Of G Protein Beta-Gamma Assembly Mediated By Phosducin-Like Protein 1, Chun Wan Jeffrey Lai

Theses and Dissertations

G-protein coupled receptor signaling (GPCR) is essential for regulating a large variety of hormonal, sensory and neuronal processes in eukaryotic cells. Because the regulation of these physiological responses is critical, GPCR signaling pathways are carefully controlled at different levels within the cascade. Phosducin-like protein 1 (PhLP1) can bind the G protein βγ dimer and participate in GPCR signaling. Recent evidence has supported the concept that PhLP1 can serve as a co-chaperone of the eukaryotic cytosolic chaperonin complex CCT/TRiC to mediate G βγ assembly. Although a general mechanism of PhLP1-mediated G βγ assembly has been postulated, many of the details about …


A General Model For Continuous Noninvasive Pulmonary Artery Pressure Estimation, Robert Anthony Smith Dec 2011

A General Model For Continuous Noninvasive Pulmonary Artery Pressure Estimation, Robert Anthony Smith

Theses and Dissertations

Elevated pulmonary artery pressure (PAP) is a significant healthcare risk. Continuous monitoring for patients with elevated PAP is crucial for effective treatment, yet the most accurate method is invasive and expensive, and cannot be performed repeatedly. Noninvasive methods exist but are inaccurate, expensive, and cannot be used for continuous monitoring. We present a machine learning model based on heart sounds that estimates pulmonary artery pressure with enough accuracy to exclude an invasive diagnostic operation, allowing for consistent monitoring of heart condition in suspect patients without the cost and risk of invasive monitoring. We conduct a greedy search through 38 possible …


Multimessenger Astronomy: Modeling Gravitational And Electromagnetic Radiation From A Stellar Binary System, Kevin Kern Dec 2011

Multimessenger Astronomy: Modeling Gravitational And Electromagnetic Radiation From A Stellar Binary System, Kevin Kern

Honors Theses

Our Solar System is one of roughly 100 billion other stars that make up the Milky Way Galaxy. Two-thirds of all stars are paired off, forming a gravitational bond between one another. Such systems are known as stellar binaries. Although these binaries are prevalent there is much yet to be learned about their formation, evolution, and interactions. The approach taken in this thesis is to produce simulated data representing the expected measurements that an observational astronomer would collect. Specifically, we have simulated the data from an eclipsing binary light curve, spectroscopic velocity curve, and the gravitational wave times series form …


Multiple Biolgical Sequence Alignment: Scoring Functions, Algorithms, And Evaluations, Ken D. Nguyen Dec 2011

Multiple Biolgical Sequence Alignment: Scoring Functions, Algorithms, And Evaluations, Ken D. Nguyen

Computer Science Dissertations

Aligning multiple biological sequences such as protein sequences or DNA/RNA sequences is a fundamental task in bioinformatics and sequence analysis. These alignments may contain invaluable information that scientists need to predict the sequences' structures, determine the evolutionary relationships between them, or discover drug-like compounds that can bind to the sequences. Unfortunately, multiple sequence alignment (MSA) is NP-Complete. In addition, the lack of a reliable scoring method makes it very hard to align the sequences reliably and to evaluate the alignment outcomes.

In this dissertation, we have designed a new scoring method for use in multiple sequence alignment. Our scoring method …


Syntactic And Semantic Analysis And Visualization Of Unstructured English Texts, Saurav Karmakar Dec 2011

Syntactic And Semantic Analysis And Visualization Of Unstructured English Texts, Saurav Karmakar

Computer Science Dissertations

People have complex thoughts, and they often express their thoughts with complex sentences using natural languages. This complexity may facilitate efficient communications among the audience with the same knowledge base. But on the other hand, for a different or new audience this composition becomes cumbersome to understand and analyze. Analysis of such compositions using syntactic or semantic measures is a challenging job and defines the base step for natural language processing.

In this dissertation I explore and propose a number of new techniques to analyze and visualize the syntactic and semantic patterns of unstructured English texts.

The syntactic analysis is …


A Horizontal Edges Bound For The Independence Number Of A Graph, Michelle Grigsby Dec 2011

A Horizontal Edges Bound For The Independence Number Of A Graph, Michelle Grigsby

Theses and Dissertations

The independence number alpha of a graph is the size of a maximum independent set of vertices. An independent set is a set of vertices where every pair of vertices in non-adjacent. This number is known to be hard to compute. The bound we worked with is defined as epsilon = max[e(v)-eh(v)] over all the vertices in the vertex set, V(G). e(v) is the number of vertices at even distance from v. eh(v) is the number of edges both of whose endpoints are at even distance from v. Epsilon can be calculated in polynomial time. Siemion Fajtlowicz proved that alpha …


Novel Near-Infrared Cyanine Dyes For Fluorescence Imaging In Biological Systems, Nilmi T. Fernando Dec 2011

Novel Near-Infrared Cyanine Dyes For Fluorescence Imaging In Biological Systems, Nilmi T. Fernando

Chemistry Dissertations

Heptamethine cyanine dyes are attractive compounds for imaging purposes in biomedical applications because of their chemical and photophysical properties exhibited in the near-infrared region. A series of meso amino-substituted heptamethine cyanine dyes with indolenine, benz[e]indolenine and benz[c,d]indolenine heterocyclic moieties were synthesized and their spectral properties including fluorescence quntum yield were investigated in ethanol and ethanol/water mixture. Upon substitution with amines, the absorption maxima of the dyes shifted to the lower wavelength region (~600 nm), showed larger Stokes shifts and stronger fluorescence which can be attributed to an excited state intramolecular charge transfer (ICT). High quantum yields …


Nucleic Acid Substrates: Investigation Of Structural And Dynamic Features That Influence Enzyme Activity, Christopher N. Johnson Dec 2011

Nucleic Acid Substrates: Investigation Of Structural And Dynamic Features That Influence Enzyme Activity, Christopher N. Johnson

Chemistry Dissertations

The previous view of DNA as a linear sequence of bases is evolving to consider structure, topology and dynamics. Sequences surrounding damage lesions have been shown to effect enzyme recognition and processing. Here we present an in depth investigation of subtle structural and dynamical features imparted to nucleic acid duplexes by a designed modification or damage lesions. Highly restrained solution structures were generated and validated utilizing a range of NMR techniques. This allowed for the characterization of multiple features of the nucleic acid duplex; such as base pairing, backbone torsion angles, deoxyribose sugar pucker, and intra and inter nucleotide proton …


Development Of A Strontium-87 Ion Interferometer, Christopher Joseph Erickson Dec 2011

Development Of A Strontium-87 Ion Interferometer, Christopher Joseph Erickson

Theses and Dissertations

I present the construction of a low-velocity intense source (LVIS) of laser-cooled neutral strontium using permanent ring magnets. The LVIS consists of a magneto-optical trap from which cold strontium is extracted in a well-collimated beam. I also present the development and implementation of a full suite of low-noise, high-bandwidth laser control electronics including a microcontroller unit. This microcontroller remotely controls and monitors the current driver, temperature controller, and PID lock circuit for each diode laser simultaneously. The current driver output is accurate to within 2 micro-amps and repeatable to with a few nano-amps. The noise spectral density of the current …


Transition Metal Complexes With Reactive Trimethylsilylchalcogenolate Ligands: Precursors For The Preparation Of Ternary Nanoclusters, Chhatra Bahadur Khadka Dec 2011

Transition Metal Complexes With Reactive Trimethylsilylchalcogenolate Ligands: Precursors For The Preparation Of Ternary Nanoclusters, Chhatra Bahadur Khadka

Electronic Thesis and Dissertation Repository

The Co2+ and Mn2+ complexes (N,N´-tmeda)Co(ESiMe3)2 (E = S, 1a; E = Se, 1b), (3,5-Me2C5H3N)2Co(ESiMe3)2 (E = S, 2a; E = Se, 2b), [Li(N,N´-tmeda)]2[(N,N´-tmeda)Mn5(μ-ESiMe3)2(ESiMe3)44-E)(μ3-E)2] (E = S, 3a; E = Se, 3b), [Li(N,N´-tmeda)]2[Mn(SSiMe3)4] (4), [Li(N,N´-tmeda)]4[Mn4(SeSiMe3)43 …


Background-Oriented Schlieren Pattern Optimization, Jeffery E. Hartberger Dec 2011

Background-Oriented Schlieren Pattern Optimization, Jeffery E. Hartberger

Theses and Dissertations

This paper describes a test series to investigate background patterns used for the Background-Oriented Schlieren field density measurement technique. Several varying background patterns were substituted under similar fluid density conditions to visualize and isolate the effects of patterns in the background images. A qualitative comparison was completed of the flow visualization results of each background pattern to categorize background conditions that improved the flow visualization image. Changes in background patterns revealed significant changes in flow visualization. Pattern contrast, spacing and sizing all played large parts in the quality of the visual density gradient imaging during the test series.


Study Of Malaria Transmission Dynamics By Mathematical Models, Yanyu Xiao Dec 2011

Study Of Malaria Transmission Dynamics By Mathematical Models, Yanyu Xiao

Electronic Thesis and Dissertation Repository

This Ph.D thesis focuses on modeling transmission and dispersal of one of the most common infectious disease, Malaria. Firstly, an integro-differential equation system is derived, based on the classical Ross-Macdonald model, toemphasize the impacts of latencies on disease dynamics. The novelty lies in the fact that different distributionfunctions are used to describe the variance of individual latencies. The theoretical results of this projectindicate that latencies reduce the basic reproduction number. Secondly, a patch model is derived to examine how travels of human beings affects the transmission and spread of Malaria. Due to coexistence of latency and dispersal, the model turns …


Thermal Plume Transport From Sand And Gravel Pits Potential Thermal Impacts On Cool-Water Streams, Jeffrey M. Markle Dec 2011

Thermal Plume Transport From Sand And Gravel Pits Potential Thermal Impacts On Cool-Water Streams, Jeffrey M. Markle

Electronic Thesis and Dissertation Repository

Potential thermal impacts from below-water-table aggregate extraction on a cool-water stream were investigated by monitoring thermal plumes, moving through an unconfined glacial-outwash aquifer, and assessing their subsurface persistence. The growing demand for aggregate and increased pressure to pursue extraction in ecologically sensitive areas has driven the need for this work. During a 10-year period, ground and surface water temperatures were measured monthly, including two periods of intensive monitoring (22 months and 2.5 years). The aquifer hydraulic conductivity (K) is quantified at the laboratory and field scale. The mean K’s from the multi-scale tests depend on test-support volume and …


Framework To Secure Cloud-Based Medical Image Storage And Management System Communications, Timothy James Rostrom Dec 2011

Framework To Secure Cloud-Based Medical Image Storage And Management System Communications, Timothy James Rostrom

Theses and Dissertations

Picture Archiving and Communication Systems (PACS) have been traditionally constrained to the premises of the healthcare provider. This has limited the availability of these systems in many parts of the world and mandated major costs in infrastructure for those who employ them. Public cloud services could be a solution that eases the cost of ownership and provides greater flexibility for PACS implementations. This could make it possible to bring medical imaging services to places where it was previously unavailable and reduce the costs associated with these services for those who utilize them. Moving these systems to public cloud infrastructure requires …


Quantum Coherence And Interference In Metallic Photonic Crystals And Hybrid Systems, Ali Hatef Dec 2011

Quantum Coherence And Interference In Metallic Photonic Crystals And Hybrid Systems, Ali Hatef

Electronic Thesis and Dissertation Repository

In the first part of the thesis, we study the absorption coefficient of quantum dots doped in metallic photonic crystals under different circumferences. We study numerically the temporal evolution of the absorption coefficient profile where a probe field is applied to monitor the absorption process in two cases, when quantum dots are embedded lightly and densely. We also studied the effect of a changing plasma frequency on the absorption profile of quantum dots two possible field configurations. We show that the changes in plasma energy can take the system from the absorption region to the transparent and gain region.

As …


A Hierarchical Image Processing Approach For Diagnostic Analysis Of Microcirculation Videos, Nazanin Mirshahi Dec 2011

A Hierarchical Image Processing Approach For Diagnostic Analysis Of Microcirculation Videos, Nazanin Mirshahi

Theses and Dissertations

Knowledge of the microcirculatory system has added significant value to the analysis of tissue oxygenation and perfusion. While developments in videomicroscopy technology have enabled medical researchers and physicians to observe the microvascular system, the available software tools are limited in their capabilities to determine quantitative features of microcirculation, either automatically or accurately. In particular, microvessel density has been a critical diagnostic measure in evaluating disease progression and a prognostic indicator in various clinical conditions. As a result, automated analysis of the microcirculatory system can be substantially beneficial in various real-time and off-line therapeutic medical applications, such as optimization of resuscitation. …


Synthesis And Characterization Of Highly Porous Borazine-Linked Polymers Via Dehydrogenation/Dehydrocoupling Of Borane-Amine Adducts And Their Applications To Gas Storage, Karl Jackson Dec 2011

Synthesis And Characterization Of Highly Porous Borazine-Linked Polymers Via Dehydrogenation/Dehydrocoupling Of Borane-Amine Adducts And Their Applications To Gas Storage, Karl Jackson

Theses and Dissertations

A new class of porous polymers has been designed and successfully synthesized by thermal dehydrogenation of several polytopic arylamine-borane adducts and has been designated Borazine-Linked Polymers (BLPs). The polymers reported are constructed of linear, triangular, and tetrahedral amine building units to form 2D and 3D frameworks. The boron sites of the pores are aligned with hydrogen atoms contrasted with the recently reported halogenated BLPs which consist of pore channels aligned with bromine or chlorine atoms. One of the reported BLPs, BLP-2(H), was proven to be crystalline by PXRD, matching the experimental pattern to theoretical patterns calculated from modeled structures. BLPs …


Bifurcations And Stability In Models Of Infectious Diseases, Bernard S. Chan Dec 2011

Bifurcations And Stability In Models Of Infectious Diseases, Bernard S. Chan

Electronic Thesis and Dissertation Repository

This work is concerned with bifurcation and stability in models related to various aspects of infections diseases.

First, we study the dynamics of a mathematical model on primary and secondary cytotoxic T-lymphocyte responses to viral infections by Wodarz et al. This model has three equilibria and the stability criteria of them are discussed. We analytically show that periodic solutions may arise from the third equilibrium via Hopf bifurcation. Numerical simulations of the model agree with the theoretical results. These dynamical behaviours occur within biologically realistic parameter range.

After studying the single-strain model, we analyze the bifurcation dynamics of an …


Screening Designs That Minimize Model Dependence, Kenneth P. Fairchild Dec 2011

Screening Designs That Minimize Model Dependence, Kenneth P. Fairchild

Theses and Dissertations

When approaching a new research problem, we often use screening designs to determine which factors are worth exploring in more detail. Before exploring a problem, we don't know which factors are important. When examining a large number of factors, it is likely that only a handful are significant and that even fewer two-factor interactions will be significant. If there are important interactions, it is likely that they are connected with the handful of significant main effects. Since we don't know beforehand which factors are significant, we want to choose a design that gives us the highest probability a priori of …