The polymerase activities involved in bovine parvoviral (BPV) DNA replication in vivo and in vitro have been described. In the in vitro system, purified and partially purified enzymes were used and the replication products were analyzed by gel electrophoresis and restriction enzyme digestion. DNA pol ૪ purified from fetal bovine liver, replicated BPV ssDNA to a unit-length covalently-linked dsDNA hairpin molecule but was unable to utilize purified BPV dsDNA as a template. Partially purified calf thymus DNA pol α replicated BPV DNA to a product 1 kbp smaller than unit-length dsDNA (11 kbp). Mapping of this product showed that the middle of the genome was under-represented. Purified pol a from bovine fetal lung (BFL) cells was capable of only end-labeling BPV ssDNA. If HeLa cell DNA pol α, which consisted of the core enzyme plus cofactors C₁ C₂, was used, the products consisted of both noncovalently- and covalently-linked unit-length dsDNA hairpin molecules. Hence, purification of pol a removed factor(s) necessary for the activity of the enzyme on B PV DNA. The polymerase activities involved in vivo in BPV DNA replication were analyzed using aphidicolin, a specific inhibitor of DNA pol α, and/or L-canavanine, an inhibitor of protein synthesis. DNA present in infected cells was visualized by autoradiography of Southern blots after probing with nick-translated BPV DNA. Aphidicolin, added at any time after-infection, reversibly inhibited each step of BPV DNA synthesis. Conversely, L-canavanine slowed the replication process, inhibited the synthesis of the viral-coded proteins NP-1 and VP3, and inhibited the production of replicative intermediates (RI) and progeny ssDNA. After removal of L-canavanine, both protein and DNA synthesis resumed. These results demonstrate that 1) pol α is involved in every stage of the replication process including the production of parental replicative form (RF), daughter RF, RI, and progeny genomes, 2) taken in conjunction with the in vitro data, that a pol α holoenzyme complex is required for BPV DNA replication, and 3) viral proteins are required for RI and progeny DNA synthesis, / Ph. D.

M.A.

We study the ħ→0 limit of the quantum dynamics determined by the Hamiltonian H(ħ) = -(ħ²/2m)Δ + Ｖ on L²(ℝⁿ) for a large class of potentials. By convolving with certain Gaussian states we obtain classically determined asymptotic behavior of the quantum evolution of states of compact support. For suitable potentials we obtain the analogus result for the scattering operator in the position representation. For initial or incoming states of class C_o¹ the error terms are shown to have L² norms of order ħ^½-ε for arbitrarily small positive ε. / Ph. D.

The question of whether or not an individual suffering from a hearing loss is capable of hearing an auditory alarm or warning is an extremely important industrial safety issue. International standard ISO 773 1—1986(E), Danger Signals for Work Places — Auditory Danger Signals, requires that any auditory alarm or warning be audible to all individuals in the workplace, including those suffering from a hearing loss and/or wearing hearing protection devices (HPDs). Very little research has been conducted to determine how an individual's hearing level affects his/her ability to detect an auditory alarm or warning in a high-noise environment while wearing an HPD. The research effort described herein was undertaken to determine how the ability to detect an alarm or warning signal changed for individuals with normal hearing and two levels of hearing loss as the levels of masking noise and alarm were manipulated. Pink noise was used as the masker since it is a generally-accepted, generic substitute for industrial noise. A heavy-equipment reverse alarm was used as the signal since it is a common alarm in industrial facilities and construction sites. The rating method paradigm of signal detection theory was used as the experimental procedure in order to separate the subjects’ absolute sensitivities to the alarm from their individual criteria for deciding to respond in an affirmative manner. Results indicated that even at a fairly low signal-to-noise ratio (0 dB), individuals with a substantial hearing loss [a pure-tone average (PTA) hearing level on the order of 45-50 dBHL in both ears] are capable of hearing the alarm while wearing a high-attenuation earmuff. Predictive models were developed using nonlinear regression techniques. These models may be used to predict whether or not individuals with known hearing levels will be capable of hearing the alarm under known conditions or to determine the level of alarm presentation in order to be heard reliably by individuals with a specified range of hearing for given noise levels / Ph. D.

The purpose of this research was to study the relationship between muscle coordination and the performance of a simple manual tracking task. The study employed an isometric, zero order, pursuit tracking task with a laterally translating, periodic sine wave forcing function. The speed of the target was varied by altering the Frequency (3 levels) of the simple sine wave. The control/response ratio for each trial was manipulated by requiring a percentage of each subject’s flexion and extension maximum voluntary contraction effort (MVC, 5 levels) to track the target. Multiple electromyograms (EMGs) of the biceps and triceps muscle groups were taken to observe flexor and extensor activity during the tracking task. Muscle modeling techniques were used to quantify the force contributions from the biceps and triceps to the observed tracking force. It was hypothesized that significant levels of co-active muscle effort would be present during the tracking task and that this co-contraction would have a unique characteristic function about the tracking conditions which yielded optimal tracking performance. The dependent measures investigated were the absolute tracking error as a proportion of the required tracking force (proportional error, PE), the absolute antagonist muscle force (AAF), and the ratio of antagonist to agonist force (co-contraction ratio, CR). Each muscle group’s maximum muscle force (MMF) required to track each condition was also determined. The experimental design was a 3 by 5 by 2 mixed factor, repeated measures ANOVA with Gender (5 male, 5 female) as the blocking variable. The ANOVA results revealed that both target Frequency and tracking Force level had significant effects on tracking error (PE). Orthogonal polynomial contrasts showed that the Frequency effect was characteristically linear while the Force effect was quadratic in nature. A polynomial regression function was used to predict PE from the Force and Frequency conditions. This model accounted for over 96% of the variance in the PE cell means. Further analysis revealed the optimal Force level for isometric tracking to be approximately 61% MVC. Analysis of the force contributions from each muscle group revealed quadratic relationships for the actual muscle force (%MMF) of the biceps during flexion and of the triceps during extension. These results show that optimal tracking performance during flexion occurs at approximately 66% of the biceps MMF and 65% of the triceps MMF during extension. Actual MMF values were consistently larger than net force values indicating that due to the presence of co-contraction, the measured force output at the wrist underestimated the actual muscle forces involved in tracking. Neither Force nor Frequency had significant effects on absolute co-activity (AAF) showing that antagonist activity remained largely constant over the tracking conditions. However, co-activity was higher for the extension phase than for the flexion phase of the task. Both Force and Frequency had significant effects on the co-contraction ratio (CR). However, no characteristic function of co-activity was found to explain the optimal tracking performance at median levels of flexion and extension force. CR increased with increasing target speed (Frequency) while it decreased with higher tracking Force levels. Since antagonist activity (AAF) remained almost constant, these results for CR must be due to changes in the level of agonist activity needed to perform the tracking task. Higher co-contraction was also found during decreasing force production (release) than for increasing force production (exertion). Since there was no significant difference in tracking error for these parts of the task, co-activity may serve to facilitate tracking performance by controlling the rate of force release. / Master of Science

An experiment was conducted to determine the effects of different acoustic characteristics of the testing environment on the measured attenuation of hearing protection devices (HPDs) when using a standard real-ear attenuation at threshold (REAT) protocol. In the experiment, three earmuffs and three earplugs were tested in two diffuse sound fields implemented in two different sound environments with different loudspeaker configurations. In the first case, the testing environment was reverberant, with frequency-specific reverberation time characteristics as specified in ANSI $3.19- 1974, "Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation of Earmuffs" and with three loudspeakers, one in each principal plane of the room. In the other case, a diffuse sound field was established within an anechoic chamber (free-field), as permitted by ANSI S12.6-1984 "Method for the Measurement of the Real-Ear Attenuation of Hearing Protectors" using four loudspeakers, one at each vertex of a tetrahedron with the subject's head center position at the centroid. Each of the environments met the requirements of the applicable ANSI standard as well as the requirements of standards adopted by several foreign countries. The experimental design allowed a direct comparison of the testing environments (reverberant vs. free-field) permitted by the two aforementioned ANSI standards. Results indicate that for both earmuffs and earplugs, the environment in which a REAT evaluation is performed has a statistically significant impact on the results of the evaluation. These results have implications for ongoing standards development efforts not only in the United States but also abroad since the testing environments investigated in this research are either required or allowed by several international standards. These international standards include: International Standard ISO 4869-1981, Canadian Standard CSA Z94.2-M1984, British Standard BSI 5108:1983, and Swedish Standard SS 882151 (1981). The impact of outlier dismissal on the results of REAT tests of HPDs was also investigated and found to have minimal impact on the results obtained in this experiment. However, this result is most likely case-specific and it is doubted that any generalizations can be made concerning outlier tests and their impact on HPD evaluations. As a side issue, it was also determined that ear canal size is highly correlated with attenuation achieved using premolded earplugs with attenuation decreasing with increasing ear canal size. No consistent gender effects were found in the analysis, indicating that gender alone may not be an important factor in determining how much attenuation can be obtained with a given HPD. Finally, the lack of a significant trial effect points to the absence of a strong practice effect over the three trials of a REAT evaluation, at least for subjects who are highly practiced in the REAT procedures. / Master of Science

The performance of a poly(ether/urea) membrane has been evaluated in a full scale reverse osmosis system. A series of experiments were conducted with six aromatic compounds - anthracene, pyrene, fluorene, 2-chlorobiphenyl, 2,4,6 trichlorophenol, and pentachlorophenol- and four volatile compounds - trichloromethane, bromodichloromethane, dibromochloromethane, and trichloroethene - as single and multi-solute contaminants. The objectives of the experiments were to determine if poly(ether/urea) membranes could produce a permeate that met maximum contaminant levels (MCL) set by the Safe Drinking Water Act (SDWA) and to correlate membrane performance with physical/chemical properties of the solute contaminants. Aromatic contaminants were removed to concentrations below the current MCLs. However, volatile contaminants were not sufficiently rejected by the membrane to meet either the MCL for total trihalomethanes or trichloroethene. Sorption onto the poly(ether/urea) was found to occur for several of the aromatic compounds tested in this research. This prevented developing any relationship between membrane performance and physical/chemical properties of the solute. / Master of Science

L’augmentation de productivité et de capacité de production est aujourd’hui au coeur des problématiques industrielles. Ceci touche particulièrement l’industrie forestière qui cherche depuis de nombreuses années à accroître sa productivité par, entre autres, des méthodes d’automatisation appliquées à leur processus de transformation du bois. Pour automatiser les méthodes d’inspection industrielle, plusieurs voies ont été empruntées jusqu’à ce jour : photométrie, ultrason, rayon-X, thermographie, etc . La technique présentée ici, l’effet trachéïde, utilise les caractéristiques de diffusion d’un laser dans les fibres de bois pour faire ressortir la densité et la direction du grain du bois. Cette technique produit rapidement une image en tons de gris de la pièce. À partir de cette image plusieurs méthodes ont été développées afin de faire ressortir les défauts sur la pièce. Une méthode de fusion des données a été mise au point afin de faire le regroupement des résultats des différentes techniques de détection. Finalement, une méthode de détection de contours adaptée à la détection des noeuds a été explorée. / Québec Université Laval, Bibliothèque 2019

The purpose of this study was to design a model to evaluate the influence of selected factors on the performance of a telephone delivery system for nutrition information and use the model to evaluate the performance of the Roanoke Dietetic Association Dial-A-Dietitian program. The Dial-A-Dietitian program was established to provide nutrition information to the public by Registered Dietitians. The model entailed a systems approach to evaluate the Roanoke Dietetic Association Dial-A-Dietitian program. The five phases of the model included Enabling Factors (inputs), the Interaction Process, Effort Factors (outputs), Performance (outcome), and Feedback. Feedback entailed the utilization of the results of the evaluation in the decision-making process for future Dial-A-Dietitian programs and their operation. The evaluation instruments, the Encounter Form and the Telephone Survey of clients, included reaction statements and attitude assessment of clients and dietitians. The data were analyzed with frequency distributions. Also the Chi Square Tests of Independence were computed to determine the relationship between the independent variables, Enabling Factors (Phase 1) and Effort Factors (Phase 3), and the dependent variable, Performance (Phase 4). The model was useful in the evaluation of the Dial-A-Dietitian program. The data analysis indicated that the Dial-A-Dietitian program was effective as measured by this model. / Ph. D.

Little research has been reported which has assessed the motor skills of children in elementary classroom situations where teacher aides have been involved in the teaching of physical education activities. The purpose of this study was to assess selected motor skills of second and fifth grade students and to determine whether the motor skills of students in classes with college aides differed significantly from the motor skills of students in classes without college aides. The children were tested on the motor skills of throwing, catching, kicking, and striking. The study was conducted over a fourteen week period of time in elementary schools located in Mercer County, West Virginia. Four hundred forty nine children participated in the study. All of the children were pre tested using an adapted form of the Ohio State University Scale of Intra-Gross Motor Assessment (1975) on the four motor skills during the first two weeks of the study. A ten week instructional period then followed for the experimental groups on each grade level, utilizing aides from an elementary physical education methods class at Concord College, located in Athens, West Virginia. The assigned college aide assisted the classroom teachers in conducting physical education activities with the experimental classes four days each week for the ten week period. The control group experienced. their regular instructional period for the interim ten week period, having the classroom teacher being solely responsible for conducting the physical education activities four days each week. Both groups received their regularly scheduled instruction from a physical education specialist one class period each week. At the completion of the ten week instructional period, all of the subjects were post tested utilizing the same instrument which was used in the pretest. A two way factorial MANOVA was applied in order to determine statistically significant differences in motor skill with respect to experimental versus control group, second and fifth grades and the interaction between them. The results indicated that there was a nonsignificant interaction between grades and experimental versus control group. Therefore, the two groups were relatively constant across the two grades. The results indicated that the classes of students with college aides scored significantly higher on the motor skills of catching, kicking, and striking, while there was no significant difference on the skill of throwing from pretest to posttest. The older children (fifth graders) scored significantly higher on the two skills of catching and kicking than did the younger children (second graders). There was no significant difference from pretest to posttest with respect to the grades on the motor skills of throwing and striking. / Ed. D.