Astronomy

The diversity of stellar death is revealed in the energy, velocity and geometry of the explosion debris ("ejecta"). Using multi-wavelength observations of gamma-ray burst (GRB) afterglows I show that GRBs, arising from the death of massive stars, are marked by relativistic, collimated ejecta ("jets") with a wide range of opening angles. I further show that the jet opening angles are strongly correlated with the isotropic-equivalent kinetic energies, such that the true relativ...

Electrical Engineering

The invention of turbo codes and low density parity check (LDPC) codes has made it possible for us for design error correcting codes with low decoding complexity and rates close to channel capacity. However, such codes have been studied in detail only for the most basic communication system, in which a single transmitter sends data to a single receiver over a channel whose statistics are known to both the transmitter and the receiver. Such a simplistic model is not valid in the case of a wireles...

Chemical Engineering

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.Pressure drops across ten prosthetic aortic heart valves have been measured under both steady and pulsatile flow using two different Newtonian liquids having viscosities of 0.01 dyne sec/cm[superscript 2] and 0.035 dyne sec/cm[superscript 2], respectively. The experimental results and the theory developed indicate that for a given aortic valve it is possible to predict peak systolic ...

Applied Physics

The main limitations of floating gate memory devices (Flash memory) are the long program (microsecond) and erase times (millisecond) inherent to the charging of floating gates using Fowler-Nordheim tunneling. An alternative to the integration of homogeneous dielectric tunnel barriers present in standard Flash memory is to use layered tunnel barriers made of high-k heterostructures. This allows for an effective lowering in barrier height under applied bias, resulting in shorter write/erase times ...

Chemical Engineering

This thesis is composed of two separate and unrelated projects. The first project examines the preparation of functional groups that can serve as immobilized bases in molecular sieves. Many heterogeneous, base catalysts are not able to promote diverse reaction types that require strong bases as catalysts. Additionally, some of the stronger solid base catalysts are sensitive to carbon dioxide and moisture in air and therefore are not easily suitable for recycling. Organic-functionalized molecular...

Geological and Planetary Sciences

The spatial and temporal coverage of geodetic data sets such as Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS) is increasing to the point where we can constrain many aspects of the deformation associated with earthquakes and volcanic eruptions. As our understanding of the kinematics of deformation improves, we can begin to explore the dynamic processes that drive seismic and volcanic deformation in tectonically active regions around the world.In this thesis,...

Electrical Engineering

NOTE: Text or symbols not renderable in plain ASCII are indicated by {...]. Abstract is included in .pdf document.A novel on-chip impedance transformation and power-combining technique, the distributed active transformer (DAT) is introduced. It overcomes the fundamental difficulties presented by silicon technology in the design of integrated rf power amplifiers. This technique efficiently combines several low-voltage push-pull amplifiers and simultaneously performs an impedance transformation to...

Astronomy

We present the results of a search for OVI absorption in the intergalactic medium (IGM) at 2 < z < 3. The measurements are taken from a set of 7 quasars observed with Keck I/HIRES. We find two classes of OVI system in the high redshift IGM. The first class is more rare (2-4 per sightline) and also quite strong (N_HI>10^{15.2}). These systems resemble hot, collisionally ionized gas at high densities, and contain complex mixtures of HI and metals at a range of temperatures. Al...

Biochemistry and Molecular Biophysics

Hereditary hemochromatosis (HH) is a prevalent genetic disorder that results in the daily excess absorption of dietary iron. If untreated this disease leads to systemic organ failure and death. HH is caused by mutations to the gene coding for a protein called HFE, a type I transmembrane glycoprotein with a demonstrated role in regulating cellular iron homeostasis. HFE binds to the cell-surface receptor transferrin receptor (TfR), a dimeric type II transmembrane glycoprotein responsible for iron ...

Astronomy

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.The thesis consists primarily of 4 parts, which are separate but related insofar as each makes use of spectra of high redshift QSOs in order to investigate the properties of intervening gaseous material. Briefly summarized, the sections are as follows:I. Wide-slit spectrophotometry of a sample of very high redshift QSOs is used to establish that the cumulative effect of the Lyman [al...

Physics

The gauge/gravity duality in the interaction between M theory objects has taught us a lot about quantum gravity. The eleven-dimensional PP-wave background provides a new arena for exploring this duality beyond flat and almost flat, i.e., weakly curved, backgrounds. In this thesis we discuss the gauge theories that describe the dynamics of interacting M theory objects, the supergravity calculations that capture these dynamics, the comparison of the two sides, and various objects (such as graviton...

Mathematics

Foulkes conjectured that for n=ab and a <= b, every irreducible module occurring as a constituent in $1_{Sym{b}wrSym{a}}^{Sym{n}}$ occurs with greater or equal multiplicity in $1_{Sym{a}wrSym{b}}^{Sym{n}}$. We generalize part of this to say those irreducibles also occur in $1_{Sym{d}wrSym{c}}^{Sym{n}}$, where cd=n and c,d >= a. We prove the generalized conjecture for a=2 and a=3, by explicitly constructing the corresponding tableaux. We also prove the multiplicity constraint for ce...

Chemical Engineering

Synthetic small-diameter vascular grafts often fail within three years of implantation. The underlying causes of graft failure are thought to be i) a mismatch in the mechanical properties between the graft and host material and ii) an inability of the graft to support the adhesion of endothelial cells. To address these two issues, artificial extracellular matrix (aECM) proteins contain elastin-like regions to provide physical integrity and cell-binding domains derived from fibronectin to promote...

Physics

In this thesis I explore two different types of limits on the time complexity of quantum computation---that is, limits on how much time is required to perform a given class of quantum operations on a quantum system. Upper limits can be found by explicit construction; I explore this approach for the problem of determining whether two graphs are isomorphic. Finding lower limits, on the other hand, usually requires appeal to some fundamental principle of the operation under consideration; I use thi...

Applied Mechanics

This thesis concerns problems of microstructure and its macroscopic consequences in multiphase elastic solids, both single crystals and polycrystals.The elastic energy of a two-phase solid is a function of its microstructure. Determining the infimum of the energy of such a solid and characterizing the associated extremal microstructures is an important problem that arises in the modeling of the shape memory effect, microstructure evolution (precipitation, coarsening, etc.), homogenization of com...

Materials Science

The temperature anisotropy of the cosmic microwave background (CMB) is now being probed with unprecedented accuracy and sky coverage by the Wilkinson Microwave Anisotropy Probe (WMAP), and will be definitively mapped by the Planck Surveyor after its launch in 2007. However, the polarization of the CMB will not be mapped with sufficient accuracy. In particular, the measurement of the curl-polarization, which may be used to probe the energy scale of the inflationary epoch, requires a large advance...

Civil Engineering

The recording of ground motions is a fundamental part of both seismology and earthquake engineering. The current state-of-the-art 24-bit continuously recording seismic station is described, with particular attention to the frequency range and dynamic range of the seismic sensors typically installed. An alternative method of recording the strong-motions would be to deploy a velocity sensor rather than an accelerometer. This instrument has the required ability to measure the strongest earth motion...

Chemistry

We use multi-scale simulation strategy to understand, improve and rationally design novel materials with desired properties in molecular nanotechnology. The areas we have studied cover from molecular electronics, nano-structured materials to carbon nanotube technology.In term of molecular and nano-electronics, first we used quantum mechanics to characterize the structure and current-voltage (I-V) performance of the Stoddart-Heath rotaxane-based programmable electronic switch. This methodology es...

Electrical Engineering

In this thesis, I examine both applied and theoretical issues in network source coding.The applied results focus on the construction of locally rate-distortion-optimal vector quantizers for networks. I extend an existing vector quantizer design algorithm for arbitrary network topologies [1] to allow for the use of side information at the decoder and for the presence of channel errors. I show how to implement the algorithm and use it to design codes for several different systems. The implementati...

Chemistry

Synthetic methods are presented for the preparation of various substituted bis(phosphino)borates. A relatively general protocol based on the delivery of a nucleophilic phosphine-containing carbanion to a borane electrophile has been developed. Preparative methods for the synthesis of substituted diarylchloroboranes from dimethyldiaryltin reagents provide the borane electrophiles. Methyldialkyl- or methyldiarylphosphines are selectively deprotonated at the phosphine-methyl using alkyl lithium bas...

Geological and Planetary Sciences

The alkali metals K, Rb and Cs, and the alkaline earth metals Ca, Sr and Ba were analyzed in the rocks, minerals, soils, snow, stream water and soil moisture films of Thompson Canyon, a glacially scoured watershed in the central crest region of the Sierra Nevada in east central California. The stable isotope dilution method was used.1. The mass balance of metals entering and leaving the watershed, the denudation rate, and chemical and mineralogical details of the weathering process: In the batho...

Biochemistry and Molecular Biophysics

In this thesis, I present a strategy for the design and development of microfluidic devices for high-throughput screening applications, such as mutant enzyme libraries expressed in prokaryotic hosts, where a few point mutations at the DNA level translates to hundreds of thousands of enzyme variants. The work falls into three main sections. Section I addresses fundamental research in polymer chemistry, where I explore the suitability of several polymers for microfluidic applications, examining pr...

Mathematics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...].Abstract is included in .pdf document.In this thesis we analyzed the simple connectivity of the Quillen complex at [...] for the classical groups of Lie type. In light of the Solomon-Tits theorem, we focused on the case where [...] is not the characteristic prime. Given (p,q) = 1. let dp(q) be the order of [...] in [...]. In this thesis we proved the following result:Main Theorem. When (p,q) = 1 we have the following resu...

Environmental Science and Engineering

This thesis concerns the biological process of iron reduction mediated by microbially produced extracellular redox-active organic molecules. Two different iron reducing bacteria were studied: Shewanella oneidensis and Pseudomonas chlororaphis. S. oneidensis can grow by reducing ferric iron [Fe(III)] as a terminal electron acceptor in anaerobic respiration (i.e. dissimilatory iron reduction). Previous studies had suggested that it produces extracellular electron shuttles as a strategy for reducin...

Biology

The aim of engineering immunity is to harness and engineer the immune system to treat infectious diseases and cancer. Towards this goal, accumulating evidence shows that the immune system can be manipulated to achieve the desired and improved functions. In the context of cancer therapy, many strategies have appeared to utilize the principle of immune defense to safely and effectively target tumor cells for destruction. These strategies fall into two categories: active immunotherapy and passive i...

Chemistry

A series of neutral and cationic group 4 and neutral group 3 model complexes of the Me2Si(eta^5-C5H4)(eta^5-3-(CMe3)-C5H3)(tBuSp) ligand have been prepared: tBuSpZrCl2(1), tBuSpZr(CH2SiMe3)2 (8), tBuSpZrMe2 (9), [tBuSpZrH2]2 (10), tBuSpZrMeCl (11), tBuSpZrMe(CH2CMe3) (12), tBuSpZrMe(CH2SiMe3) (13), tBuSpScCl(THF) (14), tBuSpScCH(SiMe3)2 (17), [tBuSpScH] (18), and tBuSpTiCl2 (19). The kinetically preferred isomers of 12 and 13 have been identified, and in both cases the syn isomer is preferred. W...

Mathematics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.This paper makes contributions to the structure theory of finite semifields, i.e., of finite nonassociative division algebras with unit. It is shown that a semifield may be conveniently represented as a 3-dimensional array of numbers, and that matrix multiplications applied to each of the three dimensions correspond to the concept of isotopy. The six permutations of three coordinates...

Mechanical Engineering

The object of this experimental investigation was to obtain some information on the effect of the orientation of a heating surface on boiling heat transfer and particularly on the "burnout point". This was achieved by electrically heating a chromax strip that was cemented to some refractory backing so as to limit the heat transfer to one surface of the strip. The heating unit could be rotated about the longitudinal axis, thus allowing tests to be carried out with the surface of the str...

Biology

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...].Abstract is included in .pdf document.Among the progeny of males carrying the inverted I chromosome, [...], individuals are found which have lost the terminal euchromatic segment of the inversion. This has been interpreted in the past (Sidorov 1940, 1941) as the result of exchange between the distal heterochromatin of the inversion and the short arm of the Y chromosome, and, indeed, the reciprocal recombinant type may be ...

Astronomy

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.Spectrograms were taken at two slit positions in the brighest portion of the Orion Nebula near the exciting star [...] Ori C. Four independent measurements were made in each slit position of the ratios of the He I lines [...], and [...] to the hydrogen lines H , H , and H , respectively. The ratios of the [OIII] lines [...] and [...] and of the [OII] lines [...] and [...] were also d...

Chemistry

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.A radiochemical and spectrophotometric investigation of the interactions between thallium (I) and thallium (III) is used to show that the majority of the thallium (I) and thallium (III) atoms in the crystalline thallium sesquihalides do not occupy equivalent positions in the crystalline lattice and that there is no strong optical interaction between thallium (I) and thallium (III) in...

Chemistry

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract in included in .pdf document.1. A method is presented for the study of the molecular weight and composition of macromolecules by observing in the ultracentrifuge their equilibrium distribution in a density gradient. The macromolecular material is centrifuged to near equilibrium in a solution of a low molecular weight solute. Under these conditions, sedimentation of the low molecular weight solute results in a co...

Social Science

The research presented in this thesis aims at understanding some of the principles by which aggregate patterns in competitive markets emerge as a result of the interactions between economic agents. Experiments are used in every step as a bridge between theory and its target applications. Each of the three self-contained chapters focuses on a different aspect of equilibrium or equilibration in a competitive framework.The objective of the first chapter is to examine the validity of the Rothschild-...

Chemistry

No Abstract Submitted.

Engineering and Applied Science

I. The one-dimensional propagation of shock waves in a perfect gas in which the pressure and the density are not necessarily uniform is investigated by seeking similarity solutions of the equations describing the non-isentropic motion of the gas. It is shown that such solutions can be found and that they can be related to specific types of compressive piston motion. In particular, the propagation of the shock resulting from the uniform compressive motion of a piston in a non-uniform gas is studi...

Computation and Neural Systems

NOTE: Text or symbols not renderable in plain ASCII are indicated bt [...]. Abstract is included in .pdf document.I built an analog very large-scale integration (VLSI) chip that learns in real-time. I have designed and tested this network in a 2 [...] complementary metal-oxide-silicon (CMOS) process. The chip was fabricated through the Metal-Oxide-Silicon Implementation Service (MOSIS). This fabricated chip contains 12 neurons, each fully connected to the other 11 neurons, but with no self-feedb...

Aeronautics

The effect of a plane discontinuity on a plane wave propagated in a cylindrical tube is calculated by variational methods. In carrying out the calculations a transmission line analogy is used and the effect of the discontinuity at a distance is represented by a capacitance placed at the discontinuity.In section 1 the equations of motion for the propagation of a small disturbance in a cylindrical tube are established, culminating in the tyro-dimensional wave equation, while the solutions to the e...

Chemistry

The synthesis and purification of p-nitrobenzoic-acetic mixed anhydride, p-methoxybenzoic-acetic mixed anhydride and benzoic-acetic mixed anhydride is described. The thermodynamic constants for the disproportionation reaction have been determined. A mechanism for this reaction is discussed. Measurements of the interaction of acetic and benzoic acids with the acetic-benzoic anhydride system have been made.The cleavage of the mixed anhydrides with nucleophilic agents is described.The synthesis of ...

Chemistry

Organic chemists at the University of New Brunswick, while investigating the alkaloid veatchine derived from Garrya veatchii, had isolated a degradation product C16H15N which they believed to be a substituted phenanthridine. A sample was submitted to us for investigation by X-ray diffraction. Using the phenanthrene-like nucleus as a "heavy atom" it was possible to determine the substituents. Difference syntheses indicated that the skeleton is not a phenanthridine but an aza-phenanthren...

Biology

Nervous systems process information about the environment in order to generate adaptive behavior. Sensory information that is obtained through different modalities, gleaned from different interactions of the animal with its surroundings, generated by different neural algorithms, or used to infer different distal stimulus properties, is often processed by distinct pathways in the brain. The auditory system compares sounds at the two ears in order to derive the location of the source. In the barn ...

Civil Engineering

An experimental investigation was made of the friction characteristics of streams with sediment load. Measurements of velocity and sediment profiles, and calculations of friction factor, f, and von Karman s constant, k, were made in a 40-foot tilting flume. Several runs were made with uniform flow and various bed configurations using sands of two sizes (.10 mm and .16 mm). For better understanding of the effect of sediment on von Karman s constant k and the friction factor, uniform clear water f...

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.In part I the various methods of determining the energy distributions of electrons are described. Reasons are given for the choice of a semi-circular focusing spectrograph. The construction of the magnet, the spectrograph box, the field measuring devices and the coincidence Geiger-Muller counters are given in considerable detail.In part II the experimental energy distributions of the...

Chemistry

No Abstract Submitted.

Electrical Engineering

The tunneling characteristics of metal contacts on n-type CdTe and p-type InAs have been measured. Both the forward and reverse bias characteristics on CdTe are in good agreement with the two-band model for the energy vs. complex momentum relationship. The presence of trapping states increased the magnitude of the tunneling current at low voltage levels by providing a two-step transition. The slope of the forward bias log J vs. V curves for tunneling through the intermediate states was reduced b...

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.An investigation of the statistical properties of the mechanics of the dust and gas structures making up the interstellar medium is carried out. The aim is to get a comprehensive picture of the general nature of the motions and structure of the interstellar material that would follow from certain simple assumptions. Comparison with observation then shows to what extent the behavior o...

Applied Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.In this thesis, we present the results of two groups of investigations of deep level defects in semiconductor material systems.Chapter 1 consists of an overview of the thesis, background information on semiconductor impurities, and a description of deep level transient spectroscopy (DLTS).Chapter 2 contains discussions of the experiments performed on transition metal silicide-silicon...

Geological and Planetary Sciences

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.PART I: A study of the shocked Coconino sandstone from Meteor Crater, Arizona, was undertaken to examine the role of porosity in the compression of rocks and in the formation of high-pressure phases. A suite of shocked Coconino specimens collected at the crater is divided into five classes, arranged in order of decreasing quartz content. The amounts of coesite, stishovite (measured b...

Chemical Engineering

Detailed measurements of the temperature and velocity distribution in the two-dimensional wake of a heated cylinder are presented. Measurements of the temperature distribution on the surface of the cylinder for various rates of heat dissipation are also included, and these data are correlated in the form of dimensionless parameters. The cylinder was 12.15 inches long and 0.190 inch in outside diameter and was placed midway between the upper and lower parallel walls of a horizontal conduit of rec...

Physics

Cloud expansion photographs of the photoelectrons produced in hydrogen, air, and argon by means of the K[alpha] radiation of Mo show that the most probable direction of emission is the same for all three gases, and forms an angle of about 70[degrees] with the x-ray beam. These angles have been measured by means of a stereoscopic comparator specially built for the purpose. The total number of tracks measured is 443. Distribution curves plotted with number of tracks starting at a given angle with ...

Mathematics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.In Chapter I the preliminary concepts are introduced and applied to the quadratic differential equations, [...], in a complete normed linear ring. In Chapters II and V the functional equation, [...] is studied under suitable assumptions and shown to be related to the Frechet differential of the above differential equation as a functional of [...]. In Chapter IV the more general funct...