This paper establishes a basis for abelian categories, then gives the statement and proof of two equivalent definitions of an abelian category, the development of the basic theory of such categories, and the proof of some theorems involving this basic theory.

Supernova (SN) 1987A focused attention on the critical role of hydrodynamic instabilities in the evolution of supernovae. To test the modeling of these instabilities, we are developing laboratory experiments of hydrodynamic mixing under conditions relevant to supernovae. Initial results were reported in J. Kane et al., Astrophys. J.478, L75 (1997) The Nova laser is used to shock two-layer targets, producing Richtmyer-Meshkov (RM) and Rayleigh-Taylor (RT) instabilities at the interfaces between the layers, analogous to instabilities seen at the interfaces of SN 1987A. Because the hydrodynamics in the laser experiments at intermediate times (3-40 ns) and in SN 1987A at intermediate times (5 s-10{sup 4} s) are well described by the Euler equations, the hydrodynamics scale between the two regimes. The experiments are modeled using the hydrodynamics codes HYADES and CALE, and the supernova code PROMETHEUS, thus serving as a benchmark for PROMETHEUS. Results of the experiments and simulations are presented. Analysis of the spike and bubble velocities in the experiment using potential flow theory and a modified Ott thin shell theory is presented. A numerical study of 2D vs. 3D differences in instability growth at the O-He and He-H interface of SN 1987A, and the design for analogous laser experiments …

A two-dimensional, two fluid model of the MHD equations has been coupled to a Monte Carlo transport model of high energy, non-Maxwellian ions. The MHD part of the model assumes complete ionization and includes a perfect gas law for a scalar pressure, a tensor artificial viscosity, electron and ion thermal conduction, electron-ion coupling, and a radiation loss term. A simple Ohm's Law is used with a B/sub theta/ magnetic field. The MHD equations were solved in Lagrangian coordinates. The conservation equations were differenced explicitly and the diffusion-type equations implicitly using the splitting technique. The Monte Carlo model solves the equation of motion for high energy ions, moving through and suffering small and large angle collisions with the fluid Maxwellian plasma. The source of high energy ions is the thermonuclear reactions of the hydrogen isotopes, or it may be an externally injected beam of neutralized ions. In addition to using the usual Maxwell averaged thermonuclear cross sections for calculating the number of reactions taking place within the Maxwellian plasma, the high energy ions may suffer collisions resulting in a reaction. In the Monte Carlo model all neutrons are assumed to escape, and all energetic ions of Z less than or equal …

Nucleon structure functions measured in neutrino-iron and antineutrino-iron charged-current interactions are presented. The data were taken in two high-energy high-statistics runs by the LAB-E detector at the Fermilab Tevatron. Structure functions are extracted from a sample of 950,000 neutrino and 170,000 antineutrino events with neutrino energies from 30 to 360 GeV. The structure functions F{sub 2} and xF{sub 3} are compared with the predictions of perturbative Quantum Chromodynamics (PQCD). The combined non-singlet and singlet evolution in the context of PQCD gives value of {Lambda}NLO,(4)/MS = 337 {+-} 28 (exp.) MeV, which corresponds to {alpha}{sub S}(M{sub Z}{sup 2}) = 0.119 {+-} 0.002 (exp.) {+-} 0.004 (theory), and with a gluon distribution given by xG(x,Q{sub 0}{sup 2} = 5GeV{sup 2}) = (2.22 {+-} 0.34) {times} (1 {minus} x){sup 4.65{+-}0.68}.

A kinetic model of the primary loop of a multi-pass pressurized water reactor power plant is developed to evaluate, by analog computer techniques, the transient response characteristics under conditions of steam generator load and reactor control rod perturbations. Using the 2-pass 28 Mw(t) SM-2 reactor as a typical plant, transient behavior patterns are illustrated and examined for a variety of load inputs, variations in plant constants, and analog model simplifications. (auth)

The purpose of this study was to find if memory load significantly affects the performance of the subjects in the before condition of a before versus after technique experiment. In order to accomplish this the alternatives were presented either before or after the stimulus, with the alternatives and stimuli being either of high-complexity or low-complexity.

The beta decay of the radioactive members of the mass-eight and -twelve triads has been studied with a spiral-orbit spectrometer having a 1.3% resolution. The end point, half-life and log-ft values respectively are: for N{sup 12}, 16.37 {+-} 0.06 MeV, 11.43 {+-} 0.05 milliseconds, and 4.17; for B{sup 12}, 13.40 {+-} 0.05 MeV, 20.6 {+-} 0.2 msec and 4.11; for B{sup 8}, 14 MeV (broad), 0.75 {+-} 0.02 sec, and 5.72; and for Li{sup 8}, 13 Mev (broad), 0.87 {+-} 0.01 sec, and 5.67. The mass excesses in millimass units are: for N{sup 12}, 22.48 {+-} 0.06; for B{sup 12}, 18.19 {+-} 0.06; for B{sup 8}, 27.08 {+-} 0.13; and for Li{sup 8}, 24.97 {+-} 0.09. The shapes of the Kurie function for the mirror pairs indicate positron and electron transitions to the same levels of the daughter nuclide, with greater percentages in the positron branches relative to the ground-state transitions because of the higher energy available. The Li{sup 8} and B{sup 8} shapes are consistent with the shape of the alpha spectrum following the decay of the Be{sup 8} daughter. Less than 1% of the Li{sup 8} transition and less than 5% of the B{sup 8} transition go to …

The government of any state has the responsibility of providing for the health, safety, welfare, education, and protection of its citizens. To accomplish these goals, states have created elaborate and complex administrative organizations staffed by thousands of bureaucrats. The increased demands of the citizens of each state upon their state governments for better education, highways, and increased protection are reflected both in the expansion of the agencies created to provide these services and, in turn, in requests for funds in ever increasing amounts to expand the scope of the services. The ability of a state to fund each agency's request is definitely limited; no state is sufficiently wealthy to grant every request. Rather, a state must make some judgment in the distribution of its limited resources (money) among competing and demanding sources. This requires planning and is called budgeting, which one writer has defined as "one of the major processes by which the use of public resources is planned and controlled."

It was the intent of this study to investigate the relationship of the concept of ego-strength to the success in vocational rehabilitation. Specifically, the study was designed to evaluate in detail certain components of ego-strength which might be significant in distinguishing between the successful and unsuccessful disabled workers referred to Goodwill Industries of Dallas for vocational diagnosis and training.

The present study was made to determine the relationship between the level of teaching effectiveness of beginning elementary teachers and three individual characteristics of prospective teachers. A secondary purpose was an attempt to improve the service rendered by the School of Education at North Texas State College, Denton, Texas, in the selection and guidance of students who indicate a desire to enter the program for preparing elementary teachers.

Thesis written Laura Kuykendall, Southwestern University's Dean of Women (1918-1935), for her Master of Arts Degree in the Department of Sociology and Economics in 1926.

The major goal of this work is to provide a means to characterize the final structure of a metal that has solidified from a melt. The thermally controlled solidification of a binary alloy, nucleated at isolated sites, is described by the evolution of a probability distribution function (PDF). The relevant equation required for propagating the PDF is developed with variables for grain size and distance to nearest neighbor. The phenomena of nucleation, growth, and impingement of the grains are discussed, and used as the basis for developing rate equations that evolve the PDF. The complementary equations describing global heat and solute transfer are discussed, and coupled with the microstructure evolution equations for grain growth and PDF evolution. The full set of equations is solved numerically and results are compared with experimental data for the plutonium 1 weight percent gallium system. The three principal results of this work are: (1) The formulation of transient evolution equations for the PDF description of nucleation, growth, and impingement of a distribution of grain sizes and locations; (2) Solution of the equations to give a correlation for final average grain size as a function of material parameters, nucleation site density, and cooling rate; and (3) …

I have performed a search for t-channel single top quark production in p{bar p} collisions at 1.96 TeV on a 366 pb{sup -1} dataset collected with the D0 detector from 2002-2005. The analysis is restricted to the leptonic decay of the W boson from the top quark to an electron or muon, tq{bar b} {yields} lv{sub l}b q{bar b} (l = e,{mu}). A powerful b-quark tagging algorithm derived from neural networks is used to identify b jets and significantly reduce background. I further use neural networks to discriminate signal from background, and apply a binned likelihood calculation to the neural network output distributions to derive the final limits. No direct observation of single top quark production has been made, and I report expected/measured 95% confidence level limits of 3.5/8.0 pb.

InGaN based light emitting devices demonstrate excellent luminescence properties and have great potential in lighting applications. Though these devices are already being produced on an industrial scale, the nature of their radiative transition is still not well understood. In particular, the role of the huge (>1MV/cm), built-in electric field in these transitions is still under debate. The luminescence characteristics of InGaN quantum well structures were investigated as a function of excitation power, temperature, and biaxial strain, with an intent of discerning the effects of the electric field and inhomogeneous indium distribution in the QW on the radiative transition. It was found that the luminescence energy did not scale only with the indium concentration but that the QW thickness must also be taken into account. The thickness affects the transition energy due to quantum confinement and carrier separation across a potential drop in the QW. The luminescence peak width was shown to increase with increased indium fraction, due to increased indium inhomogeneity. The carrier lifetime increased exponentially with QW thickness and luminescence wavelength, due to increased carrier separation. Measuring the luminescence energy and carrier lifetime as a function of excitation density showed that the electric field can be screened by strong …

In an effort to determine the details of reaction mechanisms, kinetic parameters are obtained for the following two catalytic reactions, C/sub 2/H/sub 4/ + H/sub 2/ ..-->.. C/sub 2/H/sub 6/ and C/sub 2/H/sub 6/ + H/sub 2/ ..-->.. 2 CH/sub 4/. The first reaction is carried out, for the most part, under reaction conditions (e.g. 110-200 K) which prevent complications caused by a side reaction, the surface dehydrogenation of adsorbed ethylene. The second reaction is carried out at somewhat higher temperatures (80 to 200/sup 0/C). Both reactions are studied in the pressure range 0.5 to 1000 ..mu... Extensive isotope labeling experiments are also carried out, which together with the kinetic measurements support in a self-consistent way the following mechanisms of hydrogen addition. The adsorbed species C/sub 2/H/sub 5/(a) and H(a) are found to be intermediates in both the hydrogenation and hydrogenolysis reactions. In the case of the hydrogenation reaction, the rate limiting step is found to be the irreversible addition of an adsorbed hydrogen atom to an adsorbed ethylene molecule to produce C/sub 2/H/sub 5/(a) which is further hydrogenated to produce ethane. The hydrogenolysis occurs by dissociative adsorption of ethane to produce C/sub 2/H/sub 5/(a) and H(a). In this case …

Low temperature Nonphotochemical Hole Burning (NPHB) Spectroscopy of the dye rhodamine 800 (MF680) was applied for the purpose of discerning differences between cultured normal and carcinoma ovarian surface epithelial (OSE) cells. Both the cell lines were developed and characterized at the Mayo Clinic (Rochester, MN), with the normal cell line having been transfected with a strain of temperature sensitive Simian Virus 40 Large T Antigen (SV40) for the purpose of extending the life of the cell culture without inducing permanent changes in the characteristics of the cell line. The cationic lipophilic fluorophore rhodamine 800 preferentially locates in in situ mitochondria due to the high lipid composition of mitochondria and the generation of a large negative membrane potential (relative to the cellular cytoplasm) for oxidative phosphorylation. Results presented for NPHB of MF680 located in the cells show significant differences between the two cell lines. The results are interpreted on the basis of the NPHB mechanism and characteristic interactions between the host (cellular mitochondrial) and the guest (MF680) in the burning of spectral holes, thus providing an image of the cellular ultrastructure. Hole growth kinetics (HGK) were found to differ markedly between the two cell lines, with the carcinoma cell line burning …

This research examined the relationship between sediment sample data taken at Potential Release Sites (PRSs) and storm water samples taken at selected sites in and around Los Alamos National Laboratory (LANL). The PRSs had been evaluated for erosion potential and a matrix scoring system implemented. It was assumed that there would be a stronger relationship between the high erosion PRSs and the storm water samples. To establish the relationship, the research was broken into two areas. The first area was raster-based modeling, and the second area was data analysis utilizing the raster based modeling results and the sediment and storm water sample results. Two geodatabases were created utilizing raster modeling functions and the Arc Hydro program. The geodatabase created using only Arc Hydro functions contains very fine catchment drainage areas in association with the geometric network and can be used for future contaminant tracking. The second geodatabase contains sub-watersheds for all storm water stations used in the study along with a geometric network. The second area of the study focused on data analysis. The analytical sediment data table was joined to the PRSs spatial data in ArcMap. All PRSs and PRSs with high erosion potential were joined separately to create …

The purpose of this study is to determine whether or not the Illinois Test of Psycholinguistic Abilities, including its subtests and total test scores, can be used reliably as predictors of achievement on other tests used in the diagnosis of language disorders in children.

The purpose of this study has been to create a simplified yet reliable list of literary works pertinent to medieval art; one that will serve the greatest usefulness to the largest number of students.

William Blake's poetry in Cary's novel plays an integral role, and it is the purpose of this thesis to discuss the significance of Blake's poetry in The Horse's Mouth.

This study is an attempt to ascertain if there is a relationship between academic achievement, I. Q. and social maturity in mentally retarded children in an institutional setting.

The problem of this study was to determine how capable college students are in making choices relevant to each other's success as student teachers when compared with (a) college faculty ratings, (b) the judgments of cooperating teachers, and (c) scores from two objective self-rating scales.

This thesis investigates to what extent a self-concept measure may contribute to predicting which patients in a hospital are most likely to profit from treatment.

The problem with which this investigation was concerned was to determine whether or not fear of death was related to positive future time perspective and self-esteem.