In this thesis, the three hypotheses on the nature of early L2 acquisition (the Full Transfer/Full Access view of Schwartz and Sprouse (e.g., 1996), the Minimal Trees view of Vainikka and Young-Scholten (e.g., 1996), and the Valueless Features view of Eubank (e.g., 1996)), are discussed. Analysis of the early French production by two native speakers of Moroccan Arabic is done to determine if the L1 grammar is transferred onto the L2 grammar. In particular, the phenomena of verb-raising (as determined by the verb's position vis-a-vis negation) and finiteness are examined. The results of this study indicate that the relevant structures of Moroccan Arabic do not transfer onto the emerging French grammar.

The purpose of this study was to explore heterosexual bias in the diagnosis and treatment of gay males. Two hundred-fifty (134 males and 116 females) mental health professionals from the Division of Psychotherapy (29) of the American Psychological Association participated in the study. Participants were randomly assigned to one of two case history conditions, which presented a 35-year-old male seeking therapy. Both conditions were equivalent with regards to the presenting problem (i.e., diagnostic symptoms) with the exception of his significant other (i.e., gay vs. non-gay condition). Potential bias was measured through a diagnostic rating Likert scale and a treatment plan questionnaire. Other independent variables that could potentially have an effect on diagnostic ratings were explored, such as gender, year of graduation, and theoretical orientation of the respondents. Results of the statistical analyses failed to confirm evidence of heterosexual bias. Implications for further research and training are discussed.

The main research question pertains to the relationship between time-based manufacturing competence and business performance: Is there a positive relationship between time-based manufacturing competence and business performance. The objective of the study, therefore, is to examine the relationship between time -based manufacturing competence and business performance.

Molybdenum disilicide has been predominantly used for furnace heating elements, but recently there has been interest in its use for high temperature structural applications. The reason for this increased interest stems from its desirable characteristics which are a high melting point, relatively low density, good oxidation resistance, relatively good thermal conductivity and electronically conductive. The melting point of MoSi{sub 2} is approximately 2030{degrees}C as compared to a melting point of 1340{degrees}C for the Ni-based superalloys. This could potentially give MoSi{sub 2} a big advantage over the Ni-based superalloys in turbine applications because the operating temperature can be increased resulting in an increase in turbine efficiency and reduced emissions. The relatively low density (6.25g/cm{sup 3}) compared to the Ni-based superalloys (8.9 g/cm{sup 3}) is an important advantage in turbine applications because of the need for low weight. Good oxidation resistance stems from the ability of MoSi{sub 2} to form a protective SiO{sub 2} surface layer when exposed to oxygen. Another advantageous feature of MoSi{sub 2} is its thermal conductivity which is superior to Ni-based superalloys at low temperatures and comparable to the Ni-based superalloys at high temperatures. This allows heat to be dissipated at a rate better than ceramics and comparable …

We address the problem of the DNA sequences developing a "dynamical" method based on the assumption that the statistical properties of DNA paths are determined by the joint action of two processes, one deterministic, with long-range correlations, and the other random and delta correlated. The generator of the deterministic evolution is a nonlinear map, belonging to a class of maps recently tailored to mimic the processes of weak chaos responsible for the birth of anomalous diffusion. It is assumed that the deterministic process corresponds to unknown biological rules which determine the DNA path, whereas the noise mimics the influence of an infinite-dimensional environment on the biological process under study. We prove that the resulting diffusion process, if the effect of the random process is neglected, is an a-stable Levy process with 1 < a < 2. We also show that, if the diffusion process is determined by the joint action of the deterministic and the random process, the correlation effects of the "deterministic dynamics" are cancelled on the short-range scale, but show up in the long-range one. We denote our prescription to generate statistical sequences as the Copying Mistake Map (CMM). We carry out our analysis of several DNA sequences, …

This thesis showed that low temperature (250 C) SPE of stoichiometrically balanced ion implanted GaAs layers can yield good epitaxial recovery for doses near the amorphization threshold. For 250 C anneals, most of the regrowth occurred in the first 10 min. HRTEM revealed much lower stacking fault density in the co-implanted sample than in the As-only and Ga-only samples with comparable doses. After low temp annealing, the nonstoichiometric samples had a large number of residual defects. For higher dose implants, very high temperatures (700 C) were needed to remove residual defects for all samples. The stoichiometrically balanced layer did not regrow better than the Ga-only and As-only samples. The co-implanted sample exhibited a thinner amorphous layer and a room temperature (RT) annealing effect. The amorphous layer regrew about 5 nm, suggesting that stoichiometrically balanced amorphous layers can regrow even at RT. Mechanisms for solid phase crystallization in (100)GasAs is discussed: nucleation and growth of randomly oriented crystallites and SPE. These two mechanisms compete in compound semiconductors at much lower temperatures than in Si. For the low dose As-only and Ga-only samples with low-temp anneals, both mechanisms are active. For this amorphization threshold dose, crystallites remain in the amorphous layer for …

A total of 192 largemouth bass were caught at Lake Ray Roberts, Texas (1995) to investigate five controversial bass angling techniques relative to hooking mortality. The bait types were Texas-rigged scented and non-scented plastic worms, Carolina-rigged scented and non-scented plastic worms, and live golden shiners. Overall hooking mortality was 21.87% and mortality was dependent upon bait type. Highest mortality resulted from the Texas-rigged scented lures, while the lowest mortality was generated by live golden shiners. A creel survey indicated that few anglers were having success with the investigated baits. Factors that had a confirmed effect on hooking mortality were hooking location and water temperature. Hooking mortality was not excessive compared to other similar studies.

X-ray ablation of material from the first wall and other components of an ICF (Inertial Confinement Fusion) chamber is a major threat to the laser final optics. Material condensing on these optics after a shot may cause damage with subsequent laser shots. To ensure the successful operation of the ICF facility, removal rates must be predicted accurately. The goal for this dissertation is to develop an experimentally validated x-ray response model, with particular application to the National Ignition Facility (NIF). Accurate knowledge of the x-ray and debris emissions from ICF targets is a critical first step in the process of predicting the performance of the target chamber system. A number of 1-D numerical simulations of NIF targets have been run to characterize target output in terms of energy, angular distribution, spectrum, and pulse shape. Scaling of output characteristics with variations of both target yield and hohlraum wall thickness are also described. Experiments have been conducted at the Nova laser on the effects of relevant x-ray fluences on various materials. The response was diagnosed using post-shot examinations of the surfaces with scanning electron microscope and atomic force microscope instruments. Judgments were made about the dominant removal mechanisms for each material. Measurements …

The objective of the present study was to evaluate the relationship between a set of cofactors and severity of cognitive impairment, to determine if there were any factors which significantly predicted more severe neurocognitive deficits in persons with AIDS. Twenty-four male volunteers recruited from community groups and physician referrals participated. Subjects completed several self-report questionnaires eliciting information regarding demographics and risk factor variables, in addition to a comprehensive battery of neuropsychological tests. A severity of cognitive impairment summary score was computed for each subject, reflecting both the number of impaired tests and their distance in the impaired direction from normative data. Neither CD4 count, number of months since diagnosis of AIDS, number of AIDS-related illnesses, number of recent stressors, history of head injury/LOC, history of substance use, current or past psychiatric disorder, history of learning disability nor history of other medical illness were found to be significantly related to severity of cognitive impairment in this sample, after controlling for the effects of age, level of education, estimated premorbid IQ and mood status. However, no reliable conclusions could be drawn from this study because the small sample size resulted in an unacceptably low level of statistical power for the desired regression …

The problem in this study was to determine the relationship between the scores on the three parts (reading, writing, and mathematics) of the Texas Assessment of Academic Skills Test (TAAS) and the academic success of first-year students at Clarendon College, Clarendon, Texas. High school grade-point average and gender were also included in the study. The purpose of the study was to develop an equation to predict first-year college grade-point average at Clarendon College . The predictor variables were the three parts of the TAAS Test (reading, writing, and mathematics) , high school grade-point average, and gender. The equation was developed through multiple correlation/multiple regression multivariate procedures. All statistical analyses were calculated through sub-programs of the Statistical Package for the Social Sciences (SPSS). The study was limited to using only 1992/1993 Texas high school graduates who had entered Clarendon College in the fall semesters of 1992 and 1993 directly following high school graduation. A search of Clarendon College records produced 115 students from these groups who fully met all standards defined for the study. Two predictor equations were developed. One developed through a simple regression command included all five predictor variables. The second equation was produced through a stepwise procedure. This …

The purpose of this study was to examine the reliability and validity of the Child Life Style Scale (CLSS) and clarify the underlying dimensions of the scale. Dr. Kathleen Stiles designed the 90 item CLSS to quantitatively identify life style typologies for children between eight and twelve. This questionnaire consisted of 6 scales based on Adlerian constructs of personality. They are pleasing, getting, controlling, rebelling, inadequacy, and socially useful. Ten items were deleted after an inter-judge reliability/validity study. The 80 item CLSS was administered to 314 third, fourth, and fifth graders in public and private schools in Dallas, Texas. Internal consistency coefficients for the six subscales ranged from .72 to .76 and test-retest reliability coefficients ranged from .70 to .80 (p < .001). Results from a factor analysis confirmed the original six scales but factors five and six were not strong. Exploratory factor analysis found four clear factors with internal consistency coefficients ranging from .76 to .84 and test-retest reliability coefficients ranging from .73 to .83 (p < .001). Underlying dimensions of the factors, which reflect Alfred Adler's four typologies exactly, were: Factor 1: Rebelliousness Factor 2: Social Usefulness Factor 3: Control Factor 4: Fear of Failure. Results of analysis …

My work has developed to the point where it exists within the grey area between painting and sculpture. These hybrid works necessitate the transition from creating objects to that work singularly to installations of various works that operate as a whole. The purpose of this study is to identify successful methods of making this transition through the use of the computer. The computer should provide new strategies to integrate sculpture and painting into a hybrid form.

International environmental accords frequently contain obligations that may be easily satisfied by their signatories. Observers have speculated why it is in a state`s interests to sign agreements that lack strict conditions, but policy analysts lack a coherent model explaining how such agreements are formalized. Knowledge, values, and authority are key forces that elucidate how environmental accords are developed with provisions that are easily executable. This dissertation examines the formulation of Helsinki Commission recommendations to reduce emissions of organochlorines from Nordic kraft pulp mills. The kraft pulp industry, the largest industrial pollution emitter to the Baltic Sea, is also a crucial foreign exchange earner for both Sweden and Finland. Hence, Swedes and Finns were the most active participants in regional negotiations to reduce organochlorine emissions. Key variable analysis explains how obstacles in various regional negotiations were overcome, and how parties constructed a recommendation with obligations that could be easily accommodated. The two sides never agreed about the level of risk posed by organochlorines in the marine environment. This problem influenced the strictness of pollution limits specified in the final agreement. But, the parties overcame formidable obstacles in the negotiations, including: (1) concerns about costs to industry and competitive disadvantages in the …

Public concern with respect to declining traditional values, character, and family structure in the midst of increased crime, violence, and drug use have brought American education into the political arena and under intense scrutiny. The purpose of this study was to investigate whether or not differences exist in the values fostered in private schools, public choice schools and public attendance-zone schools and whether or not there are differences in the values that are identified by students as compared with teachers. The theoretical framework for the study is based upon the beliefs that values form the foundation of human behavior and that schools influence the values of societies in which they exist.

A methodology for nondestructive assay of drum packaged radioactive waste materials is investigated using Emission Computed Tomography procedures. A requirement of this method is accurate gamma attenuation correction. This is accomplished by the use of a constant density distribution for the drum content, thereby requiring the need for a homogeneous medium. The current predominant NDA technique is the use of the Segmented Gamma Scanner. Tomographic Gamma Scanning improves upon this method by providing a low resolution three-dimensional image of the source distribution, yielding both spatial and activity information. Reconstruction of the source distribution is accomplished by utilization of algebraic techniques with a nine by six voxel model with detector information gathered over scanning intervals of ninety degrees. Construction of a linear system to describe the scenario was accomplished using a point-source response function methodology, where a 54 {times} 120 matrix contained the projected detector responses for each source-detector geometry. Entries in this matrix were calculated using the point-kernal shielding code QAD-CGGP. Validation was performed using the MCNP photon transport code. Solutions to the linear system were determined using the Non-Negative Least Squares (NNLS) algorithm and the LSMOD algorithm. A series of four scans were performed, each reconstructing the source distribution …

Charge state dependence of L-shell x-ray production cross sections have been measured for 4-14 MeV ¹⁶O^q (q=3⁺-8⁺) ions incident on ultra-clean, ultra-thin copper, and for 12 MeV ¹⁶O^q (q=3⁺-8⁺) on nickel, zinc, gallium and germanium solid foils. L-shell x-ray production cross section were measured using target foils of thickness ≤0.6 μg/cm² evaporated onto 5 μg/cm² carbon backings. Oxygen ions at MeV energies and charge state q were produced using a 3MV 9SDH-2 National Electrostatics Corporation tandem Pelletron accelerator. Different charge states, with and without K-vacancies, were produced using a post acceleration nitrogen striping gas cell or ¹²C stripping foils. L-shell x-rays from ultra-thin ₂₈Ni, ₂₉Cu,₃₀Zn,₃₁Ga, and ₃₂Ge targets were measured using a Si(Li) x-ray detector with a FWHM resolution of 135 eV at 5.9 keV. The scattered projectiles were detected simultaneously by means of silicon surface barrier detectors at angle of 45° and 169° with respect to the beam direction. The electron capture (EC) as well as direct ionization (DI) contributions were determined from the projectile charge state dependence of the target x-ray production cross sections under single collision conditions. The present work was undertaken to expand the measurements of L-shell x-ray production cross sections upon selected elements with low …

The City of Denton Pecan Creek Wastewater Treatment Facility has periodically failed effluent toxicity testing. A Toxicity Identification Evaluation has determined that Diazinon in the effluent is contributing to the observed toxicity. Chlorpyrifos is also implicated as a factor. The City of Denton constructed a half acre experimental wetland to remove Diazinon related toxicity. Results from spiking and microcosm experiments indicate that the wetland can reduce the Diazinon.

Typical accounting studies attempting to explain accounting method choice employ positive theoretical hypotheses and test for association between adoption method or adoption timing and economic measures that focus upon specific firm stakeholders. Such studies addressing the adoption and impact of SFAS 87, "Employer's Accounting for Pensions," yield mixed and contradicting results. Various researchers have suggested that traditional economic analysis often fails to capture important explanatory variables and is far too simplistic. The purpose of this study is to expand analysis by evaluating a particular accounting choice by means of three different characterizations. SFAS 106, "Employers' Accounting for Postretirement Benefits Other than Pensions," allows management to choose between two very different methods of adopting the standard. The principal question explored in this study is: why did managers of firms that employ defined benefit postretirement plans for benefits other than pensions choose to adopt SFAS 106 using a particular method? The research question is explored by means of three different characterizations: 1) a traditional economic characterization; 2) a sociopolitical characterization); and 3) a joint decision characterization. Logit methodology is used with method of SFAS 106 adoption as the binary dependent variable of interest. Results indicate that all three characterizations are important in …

The purpose of this study was to investigate the effects of self-management strategies as a means of reducing off-task and disruptive behaviors of elementary school children identified as emotionally disturbed or behavior disordered (E/BD). This study provided a practical approach for classroom teachers to implement self-management strategies in classes that include children identified as having E/BD. Five elementary school children who were formally evaluated and enrolled in a special education classroom for students with E/BD were selected to participate in the study. The study also examined the effects of the self-management procedures when targeted behaviors were monitored by peers. Four resource students from the regular education class served as peer monitors. An ABAB reversal design was used to assess the effectiveness of the self-management strategy in the special education classroom. A behavior rating scale was used at the beginning of the study to develop a baseline of student behavior and during the final phase of the intervention to measure progress. The data indicated that the self-management strategies decreased the levels off-task and disruptive behaviors for all participating students. The findings of this study substantiates previous research that suggests self-management techniques help student to manage their own behaviors.

In this study, effects of facial self-reflection and complexity of self on physiological responses were investigated. Skin conductance levels were measured during baseline and neutral conditions, then under a self-focusing condition provided by mirror reflection of the face. Subjects completed measures of self-complexity, depressive affect, self-esteem, anxiety and body image satisfaction. Eye tracking data was collected during the mirror condition. Results showed a significant effect of mirror self-reflection on physiological reactivity as measured by differences between mirror and baseline mean responses. Pre-test depressive affect was correlated with low self-esteem but not with self-complexity. Self-complexity was negatively correlated with orientation to physical appearance and positively correlated with greater differences between baseline and mirror mean reactivity. Self-complexity and depressive affect did not significantly predict physiological reactivity, although a trend was found for the influence of each variable. Post-hoc analyses showed significant group differences for both self-complexity and depressive affect on physiological reactivity, although the influence of self-complexity was in the unexpected direction. Results of this study are consistent with general findings that negative self-esteem, anxiety and depression are strongly correlated. In addition, a strong correlation was found between negative self-esteem and dissociative symptoms. Exploratory analyses of eye tracking data found no significant …

A study of the phytoplankton communities of Lake Ray Roberts was conducted at three sampling sites on two sampling dates during the summer of 1995, assessing both community structure and chlorophyll a concentrations. Eight similarity indices were then used to characterize and compare the communities of these sites. Both community similarity and chlorophyll a concentrations were evaluated using a minimum detectable difference equation to determine the amount of change that must occur in these parameters in order to be deemed statistically significant. The Bray-Curtis Index was shown to be the most adequate index evaluated, and was subsequently used in conjunction with bootstrap analysis to determine the similarity between the three sampling sites.

The work presented here evaluates the dynamics of a beam of heavy ions propagating through a chamber filled with gas. The motivation for this research stems from the possibility of using heavy ion beams as a driver in inertial confinement fusion reactors for the purpose of generating electricity. Such a study is important in determining the constraints on the beam which limit its focus to the small radius necessary for the ignition of thermonuclear microexplosions which are the source of fusion energy. Nuclear fusion is the process of combining light nuclei to form heavier ones. One possible fusion reaction combines two isotopes of hydrogen, deuterium and tritium, to form an alpha particle and a neutron, with an accompanying release of {approximately}17.6 MeV of energy. Generating electricity from fusion requires that we create such reactions in an efficient and controlled fashion, and harness the resulting energy. In the inertial confinement fusion (ICF) approach to energy production, a small spherical target, a few millimeters in radius, of deuterium and tritium fuel is compressed so that the density and temperature of the fuel are high enough, {approximately}200 g/cm{sup 3} and {approximately}20 keV, that a substantial number of fusion reactions occur; the pellet microexplosion …

This research investigated how self-managed teams get the information they need to perform their job tasks. Two important factors prompted this study: the growing importance of self-managed teams in the workplace and the impact of the information system on team performance.

This study was designed to determine if impingement and entrainment by cooling water intake at the Comanche Peak Steam Electric Station have an adverse impact upon the Squaw Creek Reservoir fish population. The yearly impingement of fish was estimated to be 262,994 of 14 species. The threadfin shad (Dorosoma petenense) accounted for 96% of this total. Entrainment of eggs and larvae for a five month period was estimated to be 15,989,987 and 42,448,794 respectively. Two fish population studies were performed on Squaw Creek Reservoir to help assess impact. It was determined that the losses due to impingement and entrainment have no adverse impact upon the fish population of Squaw Creek Reservoir.