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2003

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Normal Mixture Models For Gene Cluster Identification In Two Dimensional Microarray Data, Eric Scott Harvey Jan 2003

Normal Mixture Models For Gene Cluster Identification In Two Dimensional Microarray Data, Eric Scott Harvey

Theses and Dissertations

This dissertation focuses on methodology specific to microarray data analyses that organize the data in preliminary steps and proposes a cluster analysis method which improves the interpretability of the cluster results. Cluster analysis of microarray data allows samples with similar gene expression values to be discovered and may serve as a useful diagnostic tool. Since microarray data is inherently noisy, data preprocessing steps including smoothing and filtering are discussed. Comparing the results of different clustering methods is complicated by the arbitrariness of the cluster labels. Methods for re-labeling clusters to assess the agreement between the results of different clustering techniques …

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We Are Family: Embracing Our Lesbian, Gay, Bisexual, And Transgender (Lgbt) Family Members, Juan Battle, Cathy J. Cohen, Kenya L. Covington Cox, Angela Dews, Ernest Drucker, Angelique Harris, Robert B. Hill, James R. Lanier, Melissa Mendez, Beth E. Richie Jan 2003

We Are Family: Embracing Our Lesbian, Gay, Bisexual, And Transgender (Lgbt) Family Members, Juan Battle, Cathy J. Cohen, Kenya L. Covington Cox, Angela Dews, Ernest Drucker, Angelique Harris, Robert B. Hill, James R. Lanier, Melissa Mendez, Beth E. Richie

Social and Cultural Sciences Faculty Research and Publications

No abstract provided.

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Approaches To The Synthesis Of Novel Triptycene Dendrimers And Hyperbranched Poly(Phenylene Sulfides) And Poly(Phenylene Sulfones), Alfredo Mellace Jan 2003

Approaches To The Synthesis Of Novel Triptycene Dendrimers And Hyperbranched Poly(Phenylene Sulfides) And Poly(Phenylene Sulfones), Alfredo Mellace

Seton Hall University Dissertations and Theses (ETDs)

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Towards Developing A Natural Law Jurisprudence In The U.S. Patent System, Wendy Lim Jan 2003

Towards Developing A Natural Law Jurisprudence In The U.S. Patent System, Wendy Lim

Santa Clara High Technology Law Journal

No abstract provided.

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Spring 2003 Jan 2003

Spring 2003

University of Richmond Magazine

No abstract provided.

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Gvsu Undergraduate And Graduate Catalog, 2003-2004, Grand Valley State University Jan 2003

Gvsu Undergraduate And Graduate Catalog, 2003-2004, Grand Valley State University

Course Catalogs, 1963 - Current

Grand Valley State University 2003-2004 undergraduate and/or graduate course catalog published annually to provide students with information and guidance for enrollment.

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Development Of An Online Supplement To Reduce Ethnocentrism, Udo Fluck Jan 2003

Development Of An Online Supplement To Reduce Ethnocentrism, Udo Fluck

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

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Measurement Of The Stochasticity Of Low-Latitude Geomagnetic Temporal Variations, Mark Anthony Reynolds, James A. Wanliss Jan 2003

Measurement Of The Stochasticity Of Low-Latitude Geomagnetic Temporal Variations, Mark Anthony Reynolds, James A. Wanliss

Publications

Ground magnetometer measurements of total magnetic field strength from 6 stations at low latitudes were analyzed using power spectrum and Hurst range scaling techniques. The Hurst exponents for most of these time-series were near 0.5, which indicates stochasticity, with the highest latitude stations exhibiting some persistence with Hurst exponents greater than 0.6. Although no definite correlations are evident, the relative increase of the Hurst exponent with latitude suggests the possibility that the underlying dynamics of the magnetosphere change with latitude. This result may help quantify the dynamics of the inner magnetosphere itself without the direct presence of the solar wind …

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Flame Retardancy Of Polystyrene Nanocomposites Based On An Oligomeric Organically-Modified Clay Containing Phosphate, Xiaoxia Zheng, Charles A. Wilkie Jan 2003

Flame Retardancy Of Polystyrene Nanocomposites Based On An Oligomeric Organically-Modified Clay Containing Phosphate, Xiaoxia Zheng, Charles A. Wilkie

Chemistry Faculty Research and Publications

Novel modified clays, which may enable the formation of flame retarded polystyrene nanocomposites by melt or solution blending, have been prepared using an ammonium salt which contains an oligomeric material consisting of vinylbenzyl chloride, styrene and vinyl phosphate reacting with dimethylhexadecylamine. These nanocomposites have been characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, cone calorimetry and the evaluation of mechanical properties. Melt blending is an effective, economical way to produce intercalated nanocomposites with greatly reduced peak heat release rate and a decreased total heat release; the polymer does not all undergo thermal degradation.

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A Tolerance Initiative Versus Multicultural Education: Portraits Of Teachers In Action., Raphael Chesare Heaggans Jan 2003

A Tolerance Initiative Versus Multicultural Education: Portraits Of Teachers In Action., Raphael Chesare Heaggans

Graduate Theses, Dissertations, and Problem Reports (ETD)

Shadypine Middle School has recently implemented what they called a Teaching-for-Tolerance initiative designed to help all students become tolerant of cultural perspectives. This initiative involved teachers adding multicultural education to current curricula to show students groups of people who were discriminated and prejudiced against and their reaction to the discrimination and prejudice. Since teachers are using multicultural education as a base for this initiative, this study investigates how the tolerance initiative illustrates or exemplifies levels of multicultural education as described by Sonia Nieto. This study also investigates what the reactions of the parents and students are. This qualitative study employed …

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The Evolution Of Human Life Expectancy And Intelligence In Hunter-Gatherer Economies, Hillard Kaplan Jan 2003

The Evolution Of Human Life Expectancy And Intelligence In Hunter-Gatherer Economies, Hillard Kaplan

ESI Publications

The economics of hunting and gathering must have driven the biological evolution of human characteristics, since hunter-gatherer societies prevailed for the two million years of human history. These societies feature huge intergenerational resource flows, suggesting that these resource flows should replace fertility as the key demographic consideration. It is then theoretically expected that life expectancy and brain size would increase simultaneously, as apparently occurred during our evolutionary history. The brain here is considered as a direct form of bodily investment, but also crucially as facilitating further indirect investment by means of learning-by-doing.

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The Motivating Aspects Of Technology, Mary Ascher Jan 2003

The Motivating Aspects Of Technology, Mary Ascher

Graduate Research Papers

Motivation is the most challenging and complex issue facing educators today. There are two types of motivation: intrinsic and extrinsic. To foster life-long learning educators need to stimulate intrinsic motivation in their students. Three factors that stimulate and sustain intrinsic motivation include personal relationships, shared responsibility, and safety. The expectancy theory also identifies elements affecting motivation. Technology is a tool that fits into all of these factors to capture the students' motivation.

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Nonqualified Deferred Variable Annuities: A Product In Search Of A Coherent Theory, Tommy F. Thompson Jan 2003

Nonqualified Deferred Variable Annuities: A Product In Search Of A Coherent Theory, Tommy F. Thompson

North Dakota Law Review

No abstract provided.

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Reconsidering Gender And Investment In The Intrahousehold Decision-Making Process, Lin Johnson Iii Jan 2003

Reconsidering Gender And Investment In The Intrahousehold Decision-Making Process, Lin Johnson Iii

University Avenue Undergraduate Journal of Economics

In the very recent past, the economics of the household and the economics of development appear to be edging toward a new convergence of concern around the nature and use of assets. However, these two literatures of economics continue to exist in separate spheres. I draw from both bodies of literature in order to examine gender differences in asset portfolios. I find systematic differences in the way that certain assets held by husbands versus wives influence household decision outcomes. A clear understanding of the nature and functions of various types of assets in hands of husbands and wives is necessary …

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Simulation Of Dynamic Electrochemical Processes, John Cassidy Jan 2003

Simulation Of Dynamic Electrochemical Processes, John Cassidy

Articles

This work is designed to introduce electrochemists in a tutorial manner to the basics of modeling of electrochemical systems based primarily on diffusion equations. There is an introduction to analytical and numerical methods with examples taken from typical electrochemical experiments. The Laplace transform is used to derive the Cottrell equation and chronopotentiometry. The response of an electrode to a Gaussian concentration profile is detailed. Laplace’s equation is solved for a simple cell to determine the potential distribution. Discrete methods are employed to calculate the current time behavior following a potential step using the explicit finite difference method. Cyclic voltammetry is …

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Educating Illinois, 2003-2010: An Action Plan For Distinctiveness And Excellence, Illinois State University Jan 2003

Educating Illinois, 2003-2010: An Action Plan For Distinctiveness And Excellence, Illinois State University

Educating Illinois (2000-2018)

Strategic plan of Illinois State University

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Metrics For Evaluating Human-Robot Interactions, Michael A. Goodrich, Dan R. Olsen Jr. Jan 2003

Metrics For Evaluating Human-Robot Interactions, Michael A. Goodrich, Dan R. Olsen Jr.

Faculty Publications

Metrics for evaluating the quality of a human-robot interface are introduced. The autonomy of a robot is measured by its neglect time. The robot attention demand metric measures how much of the user’s attention is involved with instructing a robot. The free-time and fan-out metrics are two ways to measure this demand. Each of them leads to estimates of the interaction effort. Reducing interaction effort without diminishing task effectiveness is the goal of human-robot interaction design.

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The Constitutional Contributions Of John Dickinson, Robert G. Natelson Jan 2003

The Constitutional Contributions Of John Dickinson, Robert G. Natelson

Faculty Law Review Articles

This article explores the contributions of John Dickinson to the Constitution and as a member of the Continental Congress. Part II provides a brief biography of John Dickinson through the ratification debates. Part II discusses Dickinson's political philosophy. Part IV examines Dickinson's philosophy in action at the Constitutional Convention.

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Achieving Equality Of Educational Opportunity In The Wake Of Judicial Retreat From Race Sensitive Remedies: Lessons From North Carolina, Roslyn Arlin Mickleson Jan 2003

Achieving Equality Of Educational Opportunity In The Wake Of Judicial Retreat From Race Sensitive Remedies: Lessons From North Carolina, Roslyn Arlin Mickleson

American University Law Review

No abstract provided.

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A Review Of South Dakota Criminal Justice: A Study Of Racial Disparities By Richard Braunstein & (And) Steve Feimer, Elsie Meeks, Frank Pommersheim Jan 2003

A Review Of South Dakota Criminal Justice: A Study Of Racial Disparities By Richard Braunstein & (And) Steve Feimer, Elsie Meeks, Frank Pommersheim

South Dakota Law Review

No abstract provided.

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Kinetics Of Aqueous Pyrite Oxidation By Potassium Dichromate - An Experimental Study, Paul Chirita Jan 2003

Kinetics Of Aqueous Pyrite Oxidation By Potassium Dichromate - An Experimental Study, Paul Chirita

Turkish Journal of Chemistry

The kinetics of pyrite oxidation in perchloric acid solutions were investigated at temperatures ranging from 30°C to 40°C, potassium dichromate concentration from 0.001 to 0.05 mol L^{ - 1}, particle size fractions from 50 to 150 \mu m and pH values down to 2.83. The rate of the oxidation reaction is described by the following expression: r = bkS^{0.51}[K_{2}Cr_{2}O_{7}]^{0.64}[H^{+} ]^{0.22} where S is the surface area of reacting solid, r represents the amount of Fe release in solution per unit surface area per unit time, b is a stoichiometric factor, k is the rate constant, and [K_{2}Cr_{2}O_{7}] and [H^{+} ] …

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Synthesis, Characterization And Electrical Conductivity Of Poly(P-Phenylene Vinylene), Ali̇ Çirpan, Zuhal Küçükyavuz, Savaş Küçükyavuz Jan 2003

Synthesis, Characterization And Electrical Conductivity Of Poly(P-Phenylene Vinylene), Ali̇ Çirpan, Zuhal Küçükyavuz, Savaş Küçükyavuz

Turkish Journal of Chemistry

Poly(p-phenylene vinylene) (PPV) was prepared electrochemically from p-xylene-bis(diethylsulphonium chloride) in a solvent-electrolyte couple of acetonitrile-tetrabutylammonium tetrafluoroborate (TBAFB). The polymer obtained from the electrode surface was converted to PPV by the thermal elimination of diethyl sulfide, HCl and ethyl sulfide. PPV was also obtained chemically in order to investigate the effect of the synthetic method on the structure and electrical conductivity. The characterization of the polymers was carried out by means of fourier transform infrared spectrometer (FTIR), differential scanning calorimetry (DSC) and thermal gravimetry analysis (TGA) techniques. The doping effect on the conductivity of the PPV was investigated by using different …

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Characterization Of Polyphenol Oxidase From Jerusalem Artichoke (Helianthus Tuberosus), Emi̇ne Zi̇yan, Şule Pekyardimci Jan 2003

Characterization Of Polyphenol Oxidase From Jerusalem Artichoke (Helianthus Tuberosus), Emi̇ne Zi̇yan, Şule Pekyardimci

Turkish Journal of Chemistry

Polyphenol oxidases (PPO) in Jerusalem arthichoke (Helianthus tuberosus) skin and flesh were extracted and purified through (NH_{4})_{2}SO_{4} precipitation, dialysis and gel filtration chromatography. The samples obtained from ammonium sulfate precipitation and dialysis were used for the characterization of crude skin and flesh PPO. Optimum pH values were 7.5 for skin PPO and 8.0 for flesh PPO with 50 mM catechol. The optimum temperatures for skin and flesh PPO were 25 °C and 30 °C respectively with catechol. Six inhibitors were tested in the study and the most effective inhibitors were found to be sodium azide and thiourea for both flesh …

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Kinetics And Mechanism Of Oxidation Of Some Hydroxy Butyric Acid Salts By Ditelluratocuprate(Iii) In Alkaline Medium, Jin-Huan Shan, Li-Ping Wang, Shi-Gang Shen, Han-Wen Sun Jan 2003

Kinetics And Mechanism Of Oxidation Of Some Hydroxy Butyric Acid Salts By Ditelluratocuprate(Iii) In Alkaline Medium, Jin-Huan Shan, Li-Ping Wang, Shi-Gang Shen, Han-Wen Sun

Turkish Journal of Chemistry

The kinetics of oxidation of 2-hydroxy butyric acid salt (2-HBAS) and 3-hydroxy butyric acid salt (3-HBAS) by ditelluratocuprate(III) (DTC) were studied spectrophotometrically between 298.2 K and 313.2 K in alkaline medium. The reaction rate showed first order dependence in DTC and a fractional order in HBAS. It was found that the pseudo-first order rate constant k_{obs} increased with an increase in the concentration of OH^- and a decrease in the concentration of TeO_{4}^{2-}. The reaction rate changed with the position of the hydroxyl group. There was a negative salt effect. A plausible mechanism involving a pre-equilibrium of adduct formation between …

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Iridoid And Phenylpropanoid Glycosides From Phlomis Samia, P. Monocephala And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher Jan 2003

Iridoid And Phenylpropanoid Glycosides From Phlomis Samia, P. Monocephala And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher

Turkish Journal of Chemistry

From the aerial parts of Phlomis samia an iridoid glucoside, shanzhiside methylester (1), and three phenylethanoid glycosides, martynoside (2), 4''-O-acetylmartynoside (3) and samioside (4), were isolated. From the overground parts of P. monocephala two iridoid glucosides, lamiide (5) and ipolamiide (6), as well as three phenylethanoid glycosides, verbascoside (= acteoside) (7), forsythoside B (8), alyssonoside (9), and one lignan glucoside, syringaresinol 4'-O-\beta -D-glucopyranoside (10), were isolated. From the aerial parts of P. carica one phenylethanoid glycoside, verbascoside (= acteoside) (7) and three phenylpropanoid monomeric glucosides, syringin (11), dihydrosyringin (12) and coniferin (13), were isolated. The structures of the isolated compounds …

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Production Of An E. Coli Toxin Protein; Colicin A In E. Coli Using An Inducible System, İsa Gökçe, Jeremy H. Lakey Jan 2003

Production Of An E. Coli Toxin Protein; Colicin A In E. Coli Using An Inducible System, İsa Gökçe, Jeremy H. Lakey

Turkish Journal of Chemistry

Colicins are bacterial toxins that kill Escherichia coli and related cells; their mode of action is of interest in protein import and toxicology. Colicins translocate across the E. coli outer membrane and periplasm by interacting with several receptors. This translocation process involves interaction of the colicin with the outer membrane porin OmpF and subsequently with the integral membrane protein TolA. The N-terminal domain of colicin N is involved in the import process. Our aim was to produce a large quantity of colicin A for functional and structural studies. It is a prerequisite to have a correctly folded and stable protein …

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Crystal Structure Of Cis-Bis(N,N-Dimethyl-N'-Benzoylthioureato)Palladium(Ii), Göktürk Avşar, Hakan Arslan, Hans-Jurgen Haupt, Nevzat Külcü Jan 2003

Crystal Structure Of Cis-Bis(N,N-Dimethyl-N'-Benzoylthioureato)Palladium(Ii), Göktürk Avşar, Hakan Arslan, Hans-Jurgen Haupt, Nevzat Külcü

Turkish Journal of Chemistry

In this study cis-bis(N,N-dimethyl-N'-benzoylthioureato) palladium(II) is synthesised and the crystal structure is determined by X-ray diffraction methods. It crystallises in the space group P2_{1}/c, with a = 11.943(1) Å, b = 11.713(1) Å, c = 15.345(1) Å, \beta = 93.90(1)°, and D_{calc} = 1.616 g cm^{-1} for Z = 4. The Pd(II) atom is in a four-coordinate geometry consisting of two thiocarbonyl S and two carbonyl O atoms from two ligand groups. The Pd-S and Pd-O bond lengths are 2.2313(6) and 2.0211(16) Å, respectively.

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Effect Of Polyoxyethylene Chain Length And Electrolyte On The Viscosity Of Mixed Micelles, Hali̇de Akbaş, Tali̇ha Si̇di̇m, Mehmet İşcan Jan 2003

Effect Of Polyoxyethylene Chain Length And Electrolyte On The Viscosity Of Mixed Micelles, Hali̇de Akbaş, Tali̇ha Si̇di̇m, Mehmet İşcan

Turkish Journal of Chemistry

The viscosity measurements of micelles composed of mixtures of anionic/nonionic surfactants were carried out as a function of the mole fraction of surfactants. The systems studied were sodium dodecyl sulfate (SDS)-polyoxyethylene lauryl ether (C_{12}POE_{n} n = 4, 10 and 23) in water and 0.1 M sodium chloride solution. In the single systems, the relative viscosity of nonionic surfactant is greater than that of SDS, and increases with the increasing level of ethylene oxide. In the mixed surfactant systems, the relative viscosities vary at the mixed molar fraction of SDS, between 0.2 and 0.3, and then the relative viscosities of mixed …

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Purification And Characterization Of Glucose 6-Phosphate Dehydrogenase From Sheep Liver, Vedat Türkoğlu, Si̇nan Aldemi̇r, Mehmet Çi̇ftçi̇ Jan 2003

Purification And Characterization Of Glucose 6-Phosphate Dehydrogenase From Sheep Liver, Vedat Türkoğlu, Si̇nan Aldemi̇r, Mehmet Çi̇ftçi̇

Turkish Journal of Chemistry

Glucose 6-phosphate dehydrogenase (D-glucose 6-phosphate: NADP^{+} oxidoreductase, EC 1.1.1.49; G6PD) was purified from sheep liver by a simple and rapid method. The purification process consisted of two steps: preparation of the homogenate, and 2', 5'-adenosine diphosphate (ADP) Sepharose 4B affinity chromatography. Through the use of these two consecutive steps, the enzyme was purified with a yield of 35.6% and 1,920 fold, having the specific activity of 11.2 enzyme units (EU/mg protein). A K_{M} of 0.176 mM and a V_{\max} of 0.0179 EU/ml were obtained for G6-P, and 0.0194 mM and 0.0223 EU/ml for NADP^{+}. Enzymatic activity was measured spectrophotometrically according …

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Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

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