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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Garrison Keillor and American Literary Traditions

Elston, Suzanne Poteet 08 1900 (has links)
Although Garrison Keillor is perhaps best known as the creator and host of Minnesota Public Radio's A Prairie Home Companion (1974-1987), the focus of this study is his literary career. Keillor's literary accomplishments include a successful career as a writer for The New Yorker and two best-selling books about the fictional town of Lake Wobegon, Minnesota, entitled Lake Wobegon Days (1985) and Leaving Home (1987). His literary style incorporates elements from several traditions in American literature--the precise, sophisticated "New Yorker style" practiced by writers such as E. B. White and James Thurber; the oral tradition prominent in the works of Mark Twain and the nineteenth-century literary comedians; and the satiric realism associated with the small-town literature of writers such as Sherwood Anderson and Sinclair Lewis.
162

Transient Expression of BABY BOOM, WUSCHEL, and SHOOT MERISTEMLESS from Virus-Based Vectors in Cotton Explants: Can We Accelerate Somatic Embryogenesis to Improve Transformation Efficiency?

Alejos, Marcos 12 1900 (has links)
Upland cotton (Gossypium hirsutum L.) is the world's most prominent fiber crop. Cotton transformation is labor intensive and time consuming, taking 12 to 18 months for rooted T0 plants. One rate limiting step is the necessary production of somatic embryos. In other recalcitrant species, ectopic expression of three genes were shown to promote somatic embryogenesis: WUSCHEL (WUS), SHOOT MERISTEMLESS (STM), and BABY BOOM (BBM). WUS is responsible for maintaining stem-cell fate in shoot and floral meristems. STM is needed to establish and maintain shoot meristems. STM and WUS have similar functions but work in different pathways; overexpression of both together converts somatic cells to meristematic and embryogenic fate. BBM encodes an AP2/ERF transcription factor that is expressed during embryogenesis and ectopic expression of BBM reprograms vegetative tissues to embryonic growth. In prior studies, these genes were constitutively expressed, and cultures did not progress beyond embryogenesis because the embryogenic signal was not turned off. In our study, we set out to use these genes to increase the efficiency of cotton transformation and decrease the time it takes to regenerate a plant. A disarmed cotton leaf crumple virus (dCLCrV) vector delivers WUS, STM, or BBM into cotton tissue cultures through Agrobacterium tumefaciens infection. We propose that virus delivery of embryo-inducing genes is a better approach for transformation because A) inserts more than 800 nucleotides are unstable, and will spontaneously inactivate, B) virus DNA can migrate through plasmodesmata to cells around the infected cell, creating a gradient of embryonic potential, C) the virus DNA does not pass through the germ line and the seed will not contain virus. We propose this method of inducing embryogenesis will facilitate the stable transformation of cotton and will be beneficial to the cotton industry. Ectopic expression of AtBBM, AtSTM, and AtWUS GrWUS:meGFP from a constitutive CaMV 35S promoter produced plants with phenotypes similar to those described in previous studies overexpressing AtBBM, indicating that the AtBBM gene was functional. The cotton cotyledon infiltration of the pART27 constructs showed transformed cells in Coker 312 by GFP localization in the nucleus. Although GFP was detected, no visible embryos appeared from the cotyledon. Cotyledons infiltrated with Agrobacterium harboring overexpression vectors withered and aborted after ~2 weeks. The virus-based vector in tissue culture failed to increase transformation efficiency, resulting in no embryos. The combination of hormone concentration showed no contribution to increasing the transformation efficiency.
163

Vítěz Mezinárodní motocyklové šestidenní. Biografie Josefa Rabase / Winner of International Six days enduro. Biography of Josef Rabas

Knotová Vaicová, Barbora January 2021 (has links)
Master thesis focuses on the life story of Josef Rabas, the multiple world champion of the International six days enduro competition. Thesis uses biographical research together with oral history method to capture the storytelling of his life journey. The emphasis is placed not only on the chronological description of the person's life but also on the explanation and understanding of contextual impacts of the period in which he lived. Another followed line is the explanation of the chosen career path where we search for possible contradiction to family's tradition. Besides being the motorcycle racer, Josef is a grandson of the academic painter and renowned artist Václav Rabas and a son of Jan Rabas, a lawyer and one of the signatories of the "Dva tisíce slov" document. Therefore, we also emphasized the family's socio-political context.
164

Evaluation of crop development stages with TerraSAR-X backscatter signatures (2010-12) by using Growing Degree Days

Ishaq, Atif, Pasternak, René, Wessollek, Christine 13 August 2019 (has links)
TerraSAR-X images have been tested for agricultural fields of corn and wheat. The main purpose was to evaluate the impact of daily temperatures in crop development to optimize climate induced factors on the plant growth anomalies. The results are completed by utilizing Geographic Information Science, e.g. tools of ArcMap 10.3.1 and databases of ground truth and meteorological information. Synthetic Aperture Radar (SAR) images from German Aerospace Center (DLR) are acquired and the field survey datasets are sampled, each per month for three years (2010-2012) but only for the crop seasons (April-October). Correlation between SAR images and farmland anomalies is investigated in accordance with daily heat accumulations and a comparison of the three years’ SAR backscatter signatures is explained for corn and wheat. Finding the influence of daily temperatures on crops and hence on the TerraSAR-X backscatter is developed by Growing Degree Days (GDD) which appears to be the most suitable parameter for this purpose. Observation of GDD permits that the coolest year was 2010, either rest of the years were warmer and GDD accumulated in 2011 was higher as compared to that of 2012 in the first half of the year, however 2012 had rather more heat accumulation in the second half of the year. SAR backscatter from farmland depicts the crop development stages which depend upon the time when satellite captures data during the crop season. It varies with different development stages of crop plants. Backscatter of each development stage changes as the roughness and the moisture content (dielectric property) of the plants changes and local temperature directly impacts crop growth and hence the development stages.
165

Minimator: A Serious Game on Zero-Day Markets

Cseresnyes, Ehud, Sharma, Hans January 2022 (has links)
Zero-days are vulnerabilities that the software vendor does not know about and thus cannot provide a patch for. Their value has caused markets to develop, divided by the purchase intention. This thesis focuses on the white and grey markets, that is those buying to patch and those buying to exploit. While states generally have an interest in both, they currently spend money to exploit zerodays, keeping software insecure. The lack of knowledge and awareness surrounding this practice is the problem targeted in this thesis. Serious games, aiming to be both entertaining and educational, represent one opportunity to create awareness. They fit our circumstances particularly well because understanding the problem space requires adversarial thinking and lots of different concepts. Our research goal has thus been to create a serious game that accurately illuminates the dilemma experienced by states. Design science was the research strategy employed to reach the stated goal. Our main contribution is Minimator, a multiplayer, web-based game in which players, acting as states, have to protect their infrastructure and deal with zero-day markets. Additionally, we present a formal model of states’ treatment of zero-day markets developed using game theory and shown to resemble the n-players prisoners’ dilemma. An expert evaluation was conducted, delivering promising results in terms of gameplay appeal, and accuracy. A naturalistic evaluation remains, but is suggested in detail for future endeavours. Minimator is original as, to our knowledge, no similar artefact exists. It provides value by potentially creating a starting point for and encouraging an informed, public debate about the trade-off between national and infrastructure security, which is inherently political.
166

Animism in Whitman: "Multitudes" of Interpretations?

Woodbury, Rachelle Helene 07 July 2006 (has links) (PDF)
Walt Whitman used animistic techniques in his poetry and prose, specifically "Song of the Redwood Tree," "Out of the Cradle Endlessly Rocking," and Specimen Days. The term animism can be traced to the Latin root of the word, anime, which connotes a "soul" or "vitality." So, when one is talking about animistic techniques, one is speaking of the (metaphoric or realistic) ensoulment of natural objects. In the wake of a growing global crisis modern scholarship has begun reexamining the implications of this belief; often it introduces ambiguities into an otherwise comfortable relationship of unquestioned human domination. In Specimen Days, Whitman seems to have a more clear view of his natural philosophy, in which he expresses his belief that nature possesses an inherency that he envies and an ability to communicate that quality with him. However, Whitman's "Song of the Redwood Tree" is ambiguous and contradicting. Whitman creates a vision of Manifest Destiny by portraying settlers in California clearing space for houses and agriculture by cutting down the majestic redwood forests. However, this poem contains a particularly odd element: the trees have a voice. They mourn their own demise while simultaneously celebrating the arrival of the new American populace. It is a conflicting image. The animistic, majestic qualities of the trees challenge an anthropocentric view of the world, not allowing the reader to quickly disregard the extinction of the redwood forests in order to embrace American ideals of progress, which in a way defeats the more imperialistic message of the poem. Another comparison, with "Out of the Cradle Endlessly Rocking," demonstrates how important subversion of self to place is when using animistic techniques in poetry. This poem implies that animate nature is a locus for Whitman's creative genius, both inspiring his poetry and permeating it with confusion. Whitman's very engagement with the process of imagining a voice for nature inserts doubt into some of his more imperialistic pronouncements and encourages the reader to question his own previously unexamined assumptions. Animistic literary techniques have the potential to encourage an involvement with non-human nature, along with a more conscious awareness of the way we use (and abuse) that Other.
167

Relationship between History Plays and Historical Studies Through Comparing the Dramas and the Audience Receptions of Yi Sang Counts to Thirteen and Our Joyful Young Days

Jeon, Youngji 28 April 2010 (has links)
No description available.
168

HAPPY DAYS: A MODERN WOMAN’S APPROACH TO ABSURDISM THROUGH FEMINIST THEATER THEORY

Collins, Rachel 30 May 2012 (has links)
No description available.
169

Effect of Nitrogen Rates, Planting Dates, and Irrigation Regimes on Potato Production in the Eastern Shore of Virginia

Suero Mirabal, Alexis Emanuel 04 January 2024 (has links)
Potatoes in the Eastern Shore of Virginia are traditionally planted between late February and early April and harvested between early June and late August. Potato prices are usually higher early into the harvest season and decrease slowly as the season progresses. Early planting dates are desirable for farmers, as it allows them to perceive higher prices for their product, but early planting is also associated with lower air temperature during the early season, which in turn can affect plant development, water and nutrient uptake, and overall yield. Additionally, variations in soil properties often affect nutrient and water availability for plants, as well as the distribution of soil-borne insect pests. Additionally, several techniques are available to map the variations of soil properties in commercial potato fields, but little effort has been made to relate this information to the potential presence of soil-borne pests. Hence, the objective of this project was to evaluate the effect of planting dates, nitrogen (N) rates, and irrigation regimes on potato production. Two comprehensive studies were conducted between February and July 2022 and 2023. The objective of the first study was to evaluate the effect of N rates, planting dates, and soil physicochemical properties in potato production and the presence of soil-borne pests. This study was established in a split-plot design with four replications, with planting dates on the main plot and N rates and time of application on the sub-plot. Late March planting resulted in the highest total tuber yield, while early planting produced significantly larger tubers. Early March planting reduced plant development and emergence, probably due to lower air and soil temperatures. There was no interaction between planting dates and N applications. Using N rates higher than 147 kg ha-1 resulted in no significant differences in total tuber yield. Regression analyses showed that the Normalized Differences Red Edge (NDRE) is an excellent predictor of N content in plant tissue and tuber yield. Moreover, Ca and H saturation percentages were linked to wireworm damage levels using classification algorithms. Similarly, K saturation percentage was identified as a potential predictor of nematode presence in this region. A second study was established with the objective of evaluating the effect of N rates and irrigation regimes on potato production. The study was established in a split-plot design with four replications, with the irrigation method on the main plot and total N rate on the subplot. Results from these experiments showed higher growth and tuber yield when combining overhead irrigation with crop evapotranspiration (ETc) estimation. Moreover, there were no significant differences when using N rates higher than 112 kg ha-1. Overall, results from these experiments suggest no changes in current N rate recommendations for this region. Additionally, these results suggest planting in late March and using irrigation regimes based on evapotranspiration with overhead irrigation systems. Future research should focus on adaptive fertilization based on growing degree days and refinement irrigation determination practices. / Master of Science in Life Sciences / In the Eastern Shore of Virginia, nearly 4,000 acres are annually dedicated to fresh white potato farming. The established planting window extends from early March to early April, aligned with peak market demands in late April. However, this traditional planting strategy exposes crops to varying temperatures, potentially affecting water and nutrient demands, as well as overall yield. A research project consisting of two studies was conducted with the objective of evaluating the effect of planting dates, nitrogen (N) rates, and irrigation regimes on potato production. The first study was conducted with the aim of optimizing yield and nutrient management by exploring the interplay between planting dates, N rates, and application timing. The second study evaluated overhead and subsurface drip irrigation systems with irrigation regimes determined either by crop evapotranspiration (ETc) or by soil moisture content through soil water sensors (SWS). Results demonstrated that early March planting resulted in delayed emergence and overall growth due to colder temperatures, while late March plantings produced the highest tuber yields. On the irrigation front, overhead irrigation integrated with ETc estimation consistently improved plant health and augmented yield. In addition, the Normalized Differences Red Edge (NDRE) index, obtained from multispectral drone imaging, produced a significant correlation with N content in plant tissue and with total tuber yields for both studies. This suggests its high potential as a yield prediction tool. Overall, results from these studies reinforce current N rate recommendations for Virginia. Furthermore, they not only refine regional potato cultivation practices but also suggest the need for research pivoting around adaptive fertilization based on growing degree days and the potential refinement of irrigation regimens.
170

Factors governing zoysiagrass response to herbicides applied during spring green-up

Craft, Jordan Michael 29 March 2021 (has links)
Zoysiagrass (Zoysia spp.) is utilized as a warm-season turfgrass because of its density, visual quality, stress tolerance, and reduced input requirements. Turf managers often exploit winter dormancy in warm-season turfgrass to apply nonselective herbicides such as glyphosate and glufosinate to control winter annual weeds. Although this weed control strategy is common in bermudagrass (Cynodon spp.), it has been less adopted in zoysiagrass due to unexplainable turf injury. Many university extension publications recommend against applying nonselective herbicides to dormant zoysiagrass despite promotional language found in a few peer-reviewed publications and product labels. Previous researchers have used vague terminology such as "applied to dormant zoysiagrass" or "applied prior to zoysiagrass green-up" to describe herbicide application timings. These ambiguous terms have led to confusion since zoysiagrass typically has subcanopy green leaves and stems throughout the winter dormancy period. No research has sought to explain why some turfgrass managers are observing zoysiagrass injury when the literature only offers evidence that these herbicides do not injure dormant zoysiagrass. We sought to explore various herbicides, prevailing temperatures surrounding application, heat unit based application timings, and spray penetration into zoysiagrass canopies as possible contributors to zoysiagrass injury. The results indicated that a wide range of herbicides may be safely used in dormant zoysiagrass. However, as zoysiagrass begins to produce more green leaves, herbicides such as metsulfuron, glyphosate, glufosinate, flumioxazin, and diquat become too injurious. Glufosinate was consistently more injurious regardless of application timing than glyphosate and other herbicides. When temperatures were 10 °C for 7 d following treatment, a delayed effect of glyphosate and glufosinate effect on digitally-assessed green cover loss was noted on zoysiagrass sprigs. In subsequent studies on turf plugs, a 14-d incubation period at 10 °C reduced glyphosate but not glufosinate effects on turf green color reduction. Glyphosate applied at 125, and 200 GDD5C can safely be applied to zoysiagrass while glufosinate applied at the same timings caused inconsistent and often unacceptable zoysiagrass injury in field studies conducted at Blacksburg, VA, Starkville, MS, and Virginia Beach, VA. Zoysiagrass green leaf density was described as a function of accumulated heat units consistently across years and locations but variably by turf mowing height. Turf normalized difference vegetative index was primarily governed by green turf cover but reduced by herbicide treatments, especially when applied at greater than 200 GDD5C. Substantial spray deposition occurred to subcanopy tissue regardless of nozzle type, pressure and height above the zoysiagrass canopy based on spectrophotometric assessment of a colorant admixture. However, increasing nozzle height above the turf canopy and avoiding air induction type nozzles significantly reduced the percentage of green tissue exposed at lower canopy levels. Absorption of radio-labeled glyphosate and glufosinate was up to four times greater when exposed to zoysiagrass stems compared to leaves. Glyphosate translocated more than glufosinate and both herbicides moved more readily from stem to leaf than from leaf to stem / Doctor of Philosophy / Zoysiagrass (Zoysia spp.) is utilized as a warm-season turfgrass because of its density, visual quality, stress tolerance, and reduced input requirements. Being that zoysiagrass is a warm-season turfgrass, it enters a dormancy period during the winter months. During this period, zoysiagrasses' active growth is halted, and leaves lose their green color and turn a golden-brown color. The winter dormancy period presents turfgrass managers with a unique opportunity to apply nonselective herbicides such as glyphosate and glufosinate to control a broad spectrum of winter annual weeds. Although this weed control strategy is common in bermudagrass (Cynodon spp.), it has been less adopted in zoysiagrass due to turfgrass managers observing unexplainable turfgrass injury. Many university extension publications recommend against applying nonselective herbicides to dormant zoysiagrass despite language found in peer-reviewed publications and product labels suggesting they could be safely applied. Previous researchers have used vague terminology such as "applied to dormant zoysiagrass" or "applied prior to zoysiagrass green-up" to describe herbicide application timings. These terms have led to confusion about when to make these applications since zoysiagrass typically has subcanopy green leaves and stems throughout the winter dormancy period. No research has sought to explain why some turfgrass managers observe zoysiagrass injury when the literature only offers evidence that these herbicides do not injure dormant zoysiagrass. Research projects were designed to explore various herbicides, temperatures surrounding herbicide applications, application timings, and spray penetration into zoysiagrass canopies as possible contributors to zoysiagrass injury. The results indicated that a wide range of herbicides may be safely used in dormant and semidormant zoysiagrass. However, as zoysiagrass begins to produce more green leaves and stems, herbicides such as metsulfuron, glyphosate, glufosinate, flumioxazin, and diquat become too injurious and should be avoided. Across multiple research studies, glufosinate was consistently more injurious regardless of application timing than glyphosate and other herbicides. When temperatures were 10 °C for 7-d following treatment, it delayed zoysaigrass response to glyphosate and glufosinate. In a subsequent study, when temperatures were at 10 °C for a 14-d period, glyphosate and the nontreated reached 50% green cover at the same time, which suggests cold temperatures could mitigate glyphosate injury on zoysiagrass over a 14-d period. The 10 ° temperature only delayed glufosinate injury on zoysiagrass, and no safening was observed. The results also indicated that as temperatures increased, glyphosate and glufosinate rate in which injury was observed increased on the zoysiagrass. Glyphosate applied at 125, and 200 GDD5C can safely be applied to zoysiagrass while glufosinate applied at the same timings caused inconsistent and often unacceptable zoysiagrass injury in field studies conducted at Blacksburg, VA, Starkville, MS, and Virginia Beach, VA. Zoysiagrass injury increased when glyphosate and glufosinate were applied later into the spring when more green leaves were present regardless of location. Accumulated heat units and zoysiagrass green leaf density were closely related, indicating that accumulated heat units could be a useful tool for turfgrass managers to track zoysiagrass spring green-up. Substantial spray deposition was found on subcanopy zoysiagrass leaves and stems regardless of nozzle type, pressure, and height above the zoysiagrass canopy based on recovered colorant at the upper, middle and lower levels of the zoysiagrass canopy. However, avoiding air induction-type nozzles and raising spray height may slightly decrease penetration of spray droplets into a zoysiagrass subcanopy, but a large percentage of droplets still reached the middle and lower canopy layers in this research. Absorption of radio-labeled glyphosate and glufosinate was up to four times greater when applied directly to zoysiagrass stolen compared to leaves. Glyphosate translocated more than glufosinate, and both herbicides moved more readily from stem to leaf than from leaf to stem. These data suggest limiting the number of green zoysiagrass leaves at application would be an effective method to avoid injury zoysiagrass when applying nonselective herbicides

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