Astronomy

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.Model atmospheres have been constructed over a wide range of temperature and gravities. The condition of radiative equilibrium is enforced using a variation of the temperature correction scheme devised by M. Krook, thus extending the work of Gingerich to the realm of higher temperatures; flux constancy is attained to within [plus or minus]1% to a depth of [tau][subscript STD] = 10 or...

Geological and Planetary Sciences

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.This thesis integrates the data from field, petrographic, X-ray, and lead and uranium isotopic studies on the Port Radium pitchblende deposit, Great Bear Lake, Canada.The oldest rocks exposed are andesitic-dacitic bedded tuffs and flows of the Echo Bay group. Overlying detrital rocks of the Cameron Bay group were accumulated before intrusion of hypabyssal, dacitic porphyry bodies and...

Physics

A C.F.R. Wilson expansion-chamber was used to study the space-distribution of photoelectrons ejected from a gas by monochromatic x-rays. Distribution curves were obtained for electrons ejected from both the K and the L atomic energy-levels. A more isotropic space-distribution was found for electrons ejected from the L energy-levels than for those from the K energy-level. The distribution of the electrons from the L energy-levels became less isotropic with an increase in the frequency of the inci...

Chemistry

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.A magnetic nucleus located on an internal rotor is coupled not only to the rotational magnetic field generated by the end-over-end rotation of the molecule but also to the magnetic field produced by the internal rotation of the top relative to the frame. Although the importance of the nuclear-spin-internal-rotation coupling as a nuclear spin-lattice relaxation mechanism has been esta...

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.This thesis examines the problem of the coupling of gravitational radiation to its sources in the limit of weak fields and slowly-moving sources; it shows in detail how the irreversibility caused by the escape of radiation can be included in the formalism.The usual slow-motion expansions of General Relativity (EIH and post-Newtonian) have the difficulty that they are not uniformly va...

Geological and Planetary Sciences

The locations and depths of earthquakes occurring in the Walker Pass Region, California, and the surrounding area have been examined for the period from January, 1934, to December, 1963. Whenever possible, least-square computer locations programs have been used to check or revise the previously determined epicenters and origin times. In most cases, epicenters determined by machine methods are within ten kilometers of those previously assigned. Accurate depths, whenever they could be calculated, ...

Geological and Planetary Sciences

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.The Grenville Front forms the boundary between the Superior and Grenville provinces, which differ greatly in structural trends and in grade and age of major metamorphism. The Front has been claimed to be a metamorphic transition, a regional fault zone, or a combination of the two. The Lake Timagami area lies athwart the Front and is favored by good outcrop and an unusually complete g...

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.It has been suggested that very dense star clusters might play important roles in quasi-stellar sources and in the nuclei of certain galaxies, where violent events occur. Such star clusters should become unstable against relativistic gravitational collapse when, in the course of evolution, they contract down to a certain critical density. In this thesis the study of the relativistic ...

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.This thesis begins with a brief review of observations of cosmological interest and with a sketch of the "standard" spatially homogeneous and isotropic cosmological models of our Universe that are currently in vogue. Following this introduction we investigate in great detail anisotropic cosmologies and cosmological models of Bianchi Type I. Our primary goal is to understand...

Electrical Engineering

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.Muscovite mica, cleaving every 10[Angstroms], provides a crystalline insulator with uniformly parallel surfaces of well known separation ideally suited to the study of electron transport phenomena. Using a micro-splitting technique similar to that developed by Foote and Kazan, muscovite was cleaved in a vacuum of 10(^6) Torr and metal electrodes evaporated, aluminum on one side, gold...

Mathematics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.In this paper the theory of dissipative linear operators in Hilbert space developed by R. S. Phillips has been applied in the study of the Cauchy problem[...](t) + A(t)x(t) = f(t), x(o) = x[subscript o]where A(t), t [epsilon] [o,[tau]], is a family of unbounded linear operators with a common dense domain D in a Hilbert space H, f [epsilon] [...], the Hilbert space of measurable funct...

Astronomy

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.The spectral range from [lamda]3600 to [lamda]11 000 has been observed in the spectra of the Orion nebula. The large amount of dust in the nebula effects the intensity of the lines, according to their wavelengths. The correction, which takes into account this effect, has been obtained using the ratio of the Paschen to the Balmer lines, which arise from the same upper level. The unred...

Chemistry

No abstract submitted.

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.The relative frequency spectrum [...] of plasma wave resonances in the positive column of a low pressure mercury discharge tube has been shown to depend upon the parameter [...] where r[subscript w] is the radius of the column, [...] is the Debye length defined in terms of the average electron density, and [...] is the square of the average plasma frequency. This paper presents obser...

Chemistry

The work presented here encompasses two distinct areas, with the first section addressing structure-function relationships in the mechanosensitive channel of large conductance (MscL) from bacteria. A high-throughput fluorescent screening technique has been developed for the E. coli homologue of MscL. This technique has been applied to a large library of random E. coli MscL mutations to provide insights into channel function. Additionally, attempts have been made to characterize the functionally ...

Astronomy

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.The color-magnitude diagram for the globular cluster M3 has been obtained to absolute magnitude M[subscript v] = +6. The main sequence has been found, extending from M[subscript v] = +3.5 to the limit of the data. The photometric parallax of m - M = 15.63 is found by fitting the apparent magnitude diagram to O. J. Eggen s and H. L. Johnson s diagram for stars in the solar neighborhoo...

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.We show that for scalar theories without a cutoff the asymptotic form for large energies [omega] of the perturbation expansion of the Low equation in the one-meson approximation is a double power series in the coupling constant g[superscript 2]and [...]. The method applied by Gell-Mann and Low to the photon propagator in electrodynamics is used to show that if the crossing matrix has...

Engineering and Applied Science

An experimental investigation of the time delay for initiation of plastic deformation in an annealed low carbon steel is described. The delay time is determined as a function of the applied stress at temperatures of -75

Physics

The effects of spin-polarized quasiparticle transport in superconducting YBa2Cu3O(7-d) (YBCO) epitaxial films are investigated by means of current injection into perovskite ferromagnet-insulator-superconductor (F-I-S) heterostructures. Transport and magnetic properties of these CMR perovskites are first investigated by inducing lattice distortions using lattice mismatching substrates. The half-metallic nature of these perovskites provides an epitaxially grown heterostructure, ideal for injection...

Engineering and Applied Science

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.PART I.Equations for radiative transfer of energy in hot gases are presented for cases involving absorption, spontaneous emission, induced emission, and isotropic scattering. Application of these equations to energy transfer between two infinite parallel plates and also to energy transfer to the nose cone of a reentry vehicle are reviewed.The Planck and Rosseland mean free paths for ...

Engineering and Applied Science

The flow field around the injection port for secondary injection of a gas normal to a supersonic stream has been studied in a series of wind tunnel experiments. The experiments were conducted at free-stream Mach numbers of 1.38 to 4.54. Gaseous nitrogen, argon, and helium were injected through a circular hole or a transverse slot with sonic flow at the injection orifice. Data are presented which include static pressure distributions on the wall in the region of the injector, shock shapes, and in...

Chemistry

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.The Hg(II) complexes of aniline, guanidine, and ammonia have been studied potentiometrically in aqueous solution with a mercury electrode. The stability of the HgR[subscript 2][superscript ++] complexes of these compounds correlates well with their basicities. An RHgOH[superscript +] complex (R = guanidine) has been identified potentiometrically and its stability determined.Potentiom...

Chemistry

In situ characterization of cosmic dust grains typically involves impact-ionization time-of-flight mass spectrometry. Considering the performance and limitations of previous instruments, I designed and tested a novel, compact time-of-flight mass spectrometer for cosmic dust analysis. The instrument, Dustbuster, incorporates a large target area with a reflectron, simultaneously optimizing mass resolution, particle detection, and ion collection. Dust particles hit the 65-cm2 target plate and are p...

Physics

In this thesis, I present a search for scalar leptons in e+e- annihilation using the L3 detector at LEP. Data collected in 1999 and 2000, at center-of-mass energies between 192 GeV and 208 GeV, was used in this analysis.This work covered the scalar lepton searches in both SUGRA and GMSB models. To achieve this analysis, a parametrized selection was developed to handle the different event signatures in SUGRA models. Improvement of the L3 simulation and reconstruction program packages was carried ...

Biology

Object recognition requires both specificity, to ensure that stimuli with distinct behavioral relevance are distinguished, and invariance, to ensure that different instances of the same stimulus are recognized as the same under varied conditions (intensity, pitch, position, ). Psychophysical studies show that an odor can be perceived as identical over significant ranges of concentrations. Whether concentration invariance results, at least in part, from low-level neural phenomena rather than cogn...

Chemistry

Part I. The ESR spectra of cycloheptatrienyl (CHT) in several crystalline environments at temperatures ranging from 1.5[degrees] to 300[degrees]K and the methods of sample preparation are described in detail.The observed spectra are classified as:(a) High-temperature spectra--eight equally spaced lines with splittings of 3.7 to 4 gauss and intensity ratios 1:7:21:35:35:21:7:1.(b) Low-temperature spectra-highly anisotropic and different for each environment.The transitions between (a) and (b) are...

Engineering and Applied Science

A set of experiments has been performed to investigate the behaviour of intermittency in pipe flow, particularly in response to periodical disturbances at fixed frequency (up to 360 cycles per minute) which were introduced in the flow.The effects were studied at various values of Reynolds number in the transition range from Re = 2000 to 3000.The main object was to relate the input frequency of the disturbance to the output frequency of the turbulent slugs emerging at the end of the pipe (Part II...

Chemistry

Protein biosynthesis has precisely controlled accuracy, and aminoacyl-tRNA synthetases (AARSs) play an important role in charging amino acids to their cognate tRNAs with high fidelity. In some cases the misactivation of non-natural amino acids by the wild-type or mutant AARS can be utilized to incorporate these non-natural amino acids into proteins in vivo. Such technique has tremendous potentials in protein engineering and other applications. Therefore, it is essential to understand the amino a...

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.1. [Photon-neutron going to pion-nucleon].The process [photon-neutron going to pion-nucleon] is studied at high energies in both the forward and backward directions. The helicity formalism is used. Contributions from the [rho], [omega], [phi] and [pi] trajectories in the t channel and from the [...],[...], and [...] trajectories in [...] channel are included. Polarization formulae fo...

Astronomy

The various possibilities for the origin (``progenitors ) of gamma-ray bursts (GRBs) manifest in differing observable properties. Through deep spectroscopic and high-resolution imaging observations of some GRB hosts, I demonstrate that well-localized long-duration GRBs are connected with otherwise normal star-forming galaxies at moderate redshifts of order unity. Using high-mass binary stellar population synthesis models, I quantify the expected spatial extent around galaxies of coalescing neutr...

Mathematics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.A real quadratic form [...] is called copositive if [...] whenever [...]. If we associate each quadratic form [...] with a point [...] of Euclidean [...] space, then the copositive forms constitute a closed convex cone in this space. We are concerned with the extreme points of this cone. That is, with those copositive quadratic forms Q for which [...] implies [...]. We show that (1) ...

Mathematics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.A Riesz space L is said to be Egoroff, if, whenever [...] and [...], there is a sequence [...] in L such that [...] and, for each n,m, there exists an index k(n,m) such that [...]. This notion was introduced, in rather a different form, by Nakano. Banach function spaces are Egoroff, and Lorentz showed that, for any function seminorm [...], the maximal seminorm [...] among those which...

Physics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.This thesis describes the measurement of the reaction Li[superscript 6](p,n)Be[superscript 6] by slow-neutron methods, with particular attention to the Be[superscript 6] ground-state threshold. The detector response was calculated by a Monte Carlo technique and verified with a measurement of the Li[superscript 7]([alpha],n)B[superscript 10] threshold. An analysis of the shape of the ...

Physics

We report the results of four different pulsar searches, covering radio, X-ray, and gamma-ray wavelengths. These searches targeted pulsars in virtually all of their guises: young and old, long-period and short-period, accretion-powered and rotation-powered. Ten new pulsars were discovered.There are very few known gamma-ray pulsars, all of which were found by folding gamma-ray data with a pulse period known from other wavelengths. Some emission models indicate that there may be a large number of ...

Chemical Engineering

Due to the unique and difficult chemistry they perform, the aromatic ring-hydroxylating dioxygenases are of interest as industrial catalysts. Unfortunately, an application-specific array of problems limits their utility. To address these problems through laboratory evolution, I developed methods for high-throughput screening of tens of thousands of dioxygenase variants. These methods rely on a phenol detection reagent (Gibbs reagent) and can be applied to liquid cultures or to growing bacterial ...

Biology

The genetic evidence available at present indicates that certain groups of genes tend to remain linked in the various members of the genus Drosophila (Donald 1936; Sturtevant and Tan, 1937; Sturtevant, 1938a, 1940; Sturtevant and Novitaki., 1941). These elements are comparable to the arms of the chromosomes of melanogaster and have accordingly been lettered A, B, C, D, E, and F for X, IIL, IIR, IIIL, IIIR, and IV, respectively. In view of the extensive cytological studies on the various members ...

Chemistry

Part I.The Configurational Stability of Primary Grignard Reagents.Examination of the temperature dependence of the nuclear magnetic resonance spectrum of 3,3-dimethylbutylmagnesium chloride in diethyl ether solution indicates that inversion of configuration at the methylene group of this Grignard reagent occurs with an approximate rate of 10 sec.[superscript -1] at room temperature. The dependence of the rate of inversion on solvent and on the structure of the Grignard reagent is discussed in te...

Physics

1. A Model of Fermi Acceleration at Shock FrontsA model of first order Fermi acceleration at shock fronts is developed. A "fast" hydromagnetic shock is assumed to be propogating toward an isolated magnetic mirror in an otherwise uniform magnetic field which is not parallel to the shock front. The behavior of an ensemble of particles trapped between the mirror and the shock is studied and a differential equation describing the balance of particle injection into the trapping region, loss...

Chemistry

Irradiation of santonin in aprotic solvents, e. g. benzene or dioxane, gives rise only to lumisantonin, but further irradiation of lumisantonin then leads to no fewer than four new photoproducts which will be designated mazdasantonin, H, B, and J. The further photoconversion of these compounds, although considerably less striking than that of lumisantonin, has also been studied in a qualitative way.Studies of the singlet or triplet nature of these reactions provides evidence for triplet paths in...

Chemical Engineering

I. A numerical method was developed for smoothing thermodynamic data with a digital computer. As a feasibility study, data on specific volume and enthalpy from the skeleton tables of the Sixth International Conference on the Properties of Steam and from the tables of Keenan and Keyes were smoothed and interpolated. Orthogonal polynomials of temperature and pressure were used as the smoothing functions. In order to maintain thermodynamic onsistency between the smoothed values of the two thermodyn...

Chemistry

The equilibrium properties of the Ag (I) complexes of DNA have been studied potentiometrically and spectrophotometrically at ionic strength of 0.1 M (NaC10[subscript 4]) and at pH s from 5.6 to 8.0. There are at least two different complexes which form at low silver ion concentrations. The strength of association of one complex (type I binding) is pH independent. The type I complexing reaction releases no protons from the DNA. A second complex (type II binding) is stronger at high pH. This compl...

Geological and Planetary Sciences

Wind is currently the dominant geological agent acting on the surface of Mars. A study of Martian aeolian activity leads to an understanding of the forces that have sculpted the planets face over the past billion years or more and to the potential discovery of climate shifts recorded in surface wind features that reflect ancient wind patterns. This work takes advantage of newly available tools and data to reconstruct the sedimentary history reflected in aeolian features on Mars. The thesis is di...

Biology

Two classes of enzymes are responsible for modulation of intracellular phosphotyrosine levels, namely protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Together these enzymes maintain the appropriate balance of phosphoproteins required for a variety of developmental processes including axon pathfinding. In Drosophila, five receptor-like protein tyrosine phosphatases (RPTPs) regulate axon pathfinding, but little is known about their downstream signaling pathways or the mea...

Mathematics

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.Let [...][subscript i] = L[subscript 2]([...],[...]; N[subscript i], where N[subscript i] is a Hilbert space (i = 1.2). Define the operator L by Lf(x) = xf(x), and let [...][subscript I] be the characteristic function of I. We examine bounded linear operators T:[...][subscript 1][...][subscript 2] which satisfy some or all of the following conditions:(1) There exists a complex-valued...

Biochemistry and Molecular Biophysics

The early development of vertebrate embryos is characterized by massive, coordinated cell movements. These movements shape the embryo, distribute different cell types, shape complex tissues, and bring tissues into their correct spatial relationships. We have examined two early cell movements: the dorsal mesoderm of the frog embryo during gastrulation as a model for the coordinated movement of connected sheets of cells and the neural crest in the chicken embryo, as a model for cell migration.The ...

Chemistry

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.In Part I results are reported for the electrolytical reduction of iron(III), copper(II), lead(II), zinc(II), and cadmium(II) in sodium pyrophosphate media. In the cases of iron(III) and copper(II), reduction in neutral and basic pyrophosphate media is irreversible. However, if a pyrophosphate ligand is dissociated from the metal complex, a species is obtained that is reversibly redu...

Chemistry

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.This thesis consists of two parts. The first part describes a study of the spectral properties of simple molecules trapped in liquid helium-cooled rare gas matrices and the equipment used in these studies. Measurements have been made of the phosphorescence lifetimes of C[subscript 6]H[subscript 6], C[subscript 6]D[subscript 6], C[subscript 10]H[subscript 8], and C[subscript 10]D[subs...

Engineering and Applied Science

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.The object is to obtain good approximations for the ground state wave function and energy for atoms and simple molecules (e.g., H[subscript 2], HF, H[subscript 2]O, CH[subscript 4]). We neglect relativistic effects including all spin couplings and we fix the nuclear positions; thus, the Hamiltonian for a molecule with N electrons is H =[...], where V(r[subscript i]) is theelectrostat...

Engineering and Applied Science

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.An experimental investigation of the initial phase of shock produced ionization in argon, krypton, xenon, and argon-xenon mixtures has been conducted in order to elucidate the atom-atom ionization reaction and to determine the atom-atom ionization cross sections for the gases noted. A high-purity shock tube was employed to heat these gases to temperatures in the range 5000[degrees]K ...

Aeronautics

The present work investigates the applications of steady and unsteady detonation waves to air-breathing propulsion systems. The efficiency of ideal detonation-based propulsion systems is first investigated based on thermodynamics. We reformulate the Hugoniot analysis of steady combustion waves for a fixed initial stagnation state to conclude that steady detonation waves are less desirable than deflagrations for propulsion. However, a thermostatic approach shows that unsteady detonations have the...