Nine phenotypically normal purebred Hampshire and crossbred Hampshire x Yorkshire gilts were mated to purebred Hampshire boars to produce 25-day embryos for chromosomal analysis. Blood samples were drawn from five of these gilts and one of the boars for leucocyte cultures and a comparison was made between karyotypes prepared from the dam with those prepared from her 25-day embryos. The mean ovulation rate of the nine gilts was 11.8 ± 0.4. A total of 75 embryos were recovered, of which six were degenerating. In addition to the regressing embryos, several sites of complete embryo reabsorption were found. Prenatal losses were calculated to be 35.9%. The diploid number of 38 chromosomes were found in 85.9% and 90.2% of the cells counted in the leucocyte and embryo cultures, respectively. A normal chromosomal complement was displayed in all cells examined from the leucocyte culture obtained from the boar. Karyotype analyses showed only one abnormal embryo, which was monosomic for group 16. Other variations in chromosome number were described as the mechanical limitations of the technique used. If chromosomal abnormalities are constant in nature, these results would indicate that most abnormal embryos are unable to survive implantation, which is in agreement with findings of other researchers. Although the monosomic embryo had survived implantation, it is highly unlikely that it would have survived through parturition. / Master of Science

Field experiments were established on September 7, 1968, and Hay 13 and July 16, 1969, by seeding three rates (on pure live seed basis [PLS]) of several companion grasses with a constant rate of Kentucky bluegrass (Poa pratensis L.). Mixtures were irrigated and clipped to 1- and 2-in. sod residues. Objectives were to determine which mixture or mixtures could provide rapid initial establishment. with subsequent high quality, permanent turf. The improved perennial ryegrasses (Lolium perenne L.) (NK-100 and Pelo) were no more competitive in the seedling stage toward Kentucky bluegrass (Poa pratensis L.) than annual ryegrass (Lolium multiflorum L.), but they provided as rapid initial cover. However, their persistence provides a means for bluegrass encroachment during the seedling year. Seedling competition was not due to any excretions from ryegrass seeds or seedlings. Turf quality of the improved perennials was superior to annual ryegrass, but slightly lower than pure bluegrass, because of frayed leaf tips. Redtop (Agrostis alba L.) and creeping red fescue (Festuca rubra L.) were less competitive to bluegrass than the ryegrasses, but they provided little advantage in ground cover; however, turf quality was similar to pure bluegrass. It was concluded that mixtures should be designed to obtain designated populations of companion and other seedlings that are needed for sufficient initial cover. The 5% PLS in this study was higher than normally recommended on a weight basis; therefore there was no advantage from higher seeding rates. Fall seeded mixtures generally contained the most Kentucky bluegrass, and the summer seedings had the least. Low clipping reduced competition from companion grasses, especially the improved perennial ryegrasses, which allowed a uniform transition toward bluegrass dominance with turf of average quality. Sod strength was best for the pure bluegrass turf, but root development of the improved perennial ryegrasses was best. / Master of Science

Born to wealth, Marguerite Inman Davis (1870-1963), daughter of a New York cotton broker of Southern lineage, grew up in the best societies of Georgia and New York and studied piano in Bonn and Paris. After her marriage to Westmoreland Davis in 1893, she continued to travel extensively in Europe and the Orient. In 1903, after she and her husband purchased the 1,500 acre Morven Park estate in Loudoun County, Virginia, Mrs. Marguerite Inman Davis assumed the life of a hostess and pursued her talents as an equestrienne and gardener. As first lady of Virginia during World War I, Marguerite Davis consciously set an example for women·of the state and nation to enter war work. She volunteered, as president of the Woman's Munition Reserve, to sew silk bags and fill them with smokeless gun powder at Seven Pines outside Richmond. Later she helped save a peach crop from ruin during the war labor shortage. In the course of the Spanish influenza epidemic which swept Richmond between October, 1918, and November, 1919, she served as a volunteer nurse in the pneumonia ward of the John Marshall Emergency Hospital. Yet, while Marguerite Davis played the role of a modern woman and patriot, she also maintained the tradition of southern gentility and hospitality. Entertaining groups of soldiers, students, politicians, and suffragettes, she democratically made the people of the Old Dominion very much at home in the executive mansion during the Davis administration (1918-1922). From her husband’s defeat in the 1922 senatorial primary until her death, Mrs. Davis contributed generously to many philanthropic and social causes. Unable personally to work in the war effort of World War II as she had in World War I, Marguerite Davis donated two ambulances, several pedigreed Doberman Pinschers, and invested a large part of her husband's estate in war bonds. Throughout her life, Marguerite was generous in giving scholarships to deserving Virginia students. Mrs. Davis retired from public life after the death of her husband in 1943, and moved to her sister's home in Branford, Connecticut. She continued, however, despite her advancing age to attack the state of Virginia politics. Inflamed by the laudatory eulogies heaped upon Senator Carter Glass at his death in 1947, Mrs. Davis publicly condemned both Glass and the Byrd organization. In establishing the Westmoreland Davis Memorial Foundation, Marguerite Inman Davis displayed enlightened philanthropic views by providing munificently not only for ordinary scholarships but to make historic Morven Park an endowed center. She remained at Branford, Connecticut, until her death on July 15, 1963. / Master of Arts

The basic objective of this study was to identify relevant variables that are significant to the pedestrian effect on vehicle flow at at-grade intersections. The data on these variables were collected and analyzed to determine if a statistical relationship existed between these selected variables and the vehicle seconds of delay being caused by pedestrian-vehicle function as a result of both vehicular and pedestrian movements at the study intersections. The multiple regression analysis of the data for this study produced three regression models which should give accurate estimates of the vehicle seconds of delay. The first model included the data for all six study intersections, three with all one-way streets intersecting and three with one one-way streets and one two-way street connecting. The second model was applied to three intersections with one-way streets intersecting. The third model was derived from the data on three intersections with two one-way street legs and two two-way street legs. These models all have high multiple correlation coefficients, 0.93 or above, and passed F tests at 0.10 level of significance. Therefore, a definite statistical relationship was found to explain the pedestrian effects on vehicle delay at typical urban intersections. It is hoped that this study will stimulate further research and development in the field of pedestrian effect on vehicle flow at at-grade intersections. / Master of Science

This thesis is a report on an experimental study done on a new type of microwave device. This device is a monolithic, integrated circuit which uses “lumped” elements to approximate a distributed-parameter active RC line. The active region of this device are IMPATT diodes which are capable of generating negative conductance effects (through transit-time delays of majority carriers) at microwave frequencies. The combined effect of negative conductance and positive real resistance within the device makes it capable of being a microwave amplifier or oscillator. The advantage of this type of device is that it does not have to present a negative impedance to an external signal source (as is the case with parametric amplifiers) to accomplish gain. Due to the nature of its design, it is inherently more “broadbanded” than the parametric amplifier. Also, no external “pump” is needed since the device obtains gain by an entirely different principle. In the following pages a brief description of the basic operating theory of the device will be given. This description will show how the negative conductance effect is generated and how this is incorporated into the design of the final active network. Following this is a detailed discussion of experimental procedure, device characteristics sought, and the results obtained. The results of testing show that this device is capable of functioning as a microwave amplifier. They also show that more work will have to be done in improving the "packaging” of the device. Aside from these "packaging” problems, it appears that this device is the key to a new area of microwave semiconductor devices. / Master of Science

The increasing amounts of initial capital investments in the chemical and petroleum industry are making accurate and realistic economic analyses a necessity. The purpose of this investigation was to develop a general economic evaluation model which was an improvement over previous analysis techniques. The new aspect of this model is its capability of analysing multiple investments with a comprehensive risk analysis and with a short computer running time. Significant features of the analysis technique include: (1) A general and flexible computer model which can easily be applied to a wide range of capital investment decisions, (2) The use of present value for a consistent and realistic economic evaluation criterion, (3) Consideration of the future economic environment through the capability of predicting the time-dependent changes of the main variables, (4) Monte Carlo risk analysis to determine the effect of uncertainty in the 14 main variables, (5) Two-plant analysis with the advantage of a delayed decision on the second plant, and (6) Execution in a relatively short computer running time (six minutes on IBM 360, 65). / Master of Science

This research involved the development of a laboratory procedure, consisting of two variations, and a wear test method for wrinkling fabrics. The intent of the laboratory testing was to have the results obtained simulate those received from the wear test, thus alleviating the need for future wear testing. The· fabrics tested were three Dacron® polyester/wool blends and one 100% wool from Burlington Worsteds Division. The laboratory method consisted of balling the wet or dry samples, wrapping them in commercial plastic wrap, securing the packages with elastic bands and subjecting them to centrifugal force in the Bock Extractor. The wear test utilized 14-inch squares of the fabrics, which were hand basted to the fronts of four nylon tricot half slips, and were worn by four subjects for.sit hour ·periods. Rating, to the nearest tenth, was performed by a panel of three trained judges using AATCC Method 88A-1964. The samples were evaluated immediately following laboratory wrinkling or removal of test garment and again following a twenty minute recovery period in a conditioning room exhibiting 70 ± 2 degrees Fahrenheit and 65 ± 2 per cent humidity. Statistical analysis involved Analysis of Variance and Duncan’s New Multiple Range Test. Major conclusions of this research were: 1. Dry laboratory testing and wear testing showed no significant differences among original sample ratings. All recovery ratings were above a 4.2. 2. All four fabrics received extremely lower ratings when tested wet. 3. The 100% wool fabric received the best overall ratings when dry and the worst ratings when wet. 4. The two lighter weight blends behaved similarly throughout testing. 5. The dry laboratory results correlate with those of the wear test. All four fabrics showed a slight degree of muzziness. Therefore, based on this research data, a prediction cannot be made as to how a fabric with severe muzziness characteristics would perform. / Master of Science

Synchronous cultures of Chlorella pyrenoidosa (strain 7- 11-05) have been utilized to measure the potential expression of the structural gene for isocitrate lyase (three D_S-Isocitrate glyoxylate-lyase, EC 4.1.3.1) during the cell cycle. Synthesis of the enzyme could be induced by placing cultures in the dark on acetate, with the induction process occurring in a quadratic fashion. By addition of cycloheximide during the course of induction, the increase in isocitrate lyase activity was shown to result from de novo protein synthesis. In the absence of protein synthesis the enzyme was stable for at least five hours. The pattern of uninduced isocitrate lyase synthesis during the cell cycle in continuous light, paralleled the stepwise increase of total cellular DNA. The enzyme appeared to be fully repressed for most of the cell cycle, and was derepressed during the time of DNA replication. Isocitrate lyase could be induced at all times in the cell cycle, indicating that the potential for gene expression is continuous in this eukaryote. A time lag was observed between the beginning of DNA replication and the initial rise in potential for isocitrate lyase gene expression. The control of gene expression in Chlorella appeared to be similar to that found in a fission yeast. / Ph. D.

Québec Université Laval, Bibliothèque 2014

Montréal Trigonix inc. 2018