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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.
11

Rice domestication in the middle Yangtze Region, China : an application of phytolith analysis /

Zhao, Zhijun, January 1996 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 279-302). Also available on the Internet.
12

Rice domestication in the middle Yangtze Region, China an application of phytolith analysis /

Zhao, Zhijun, January 1996 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 279-302). Also available on the Internet.
13

Cutting propagation and container production of Rudy Haag burning bush [Euonymus alatus 'Rudy Haag']

Poston, Amy Lynn, January 2007 (has links) (PDF)
Thesis (M.S.)--University of Kentucky, 2007. / Title from document title page (viewed on June 28, 2007). Document formatted into pages; contains: vii, 74 p. Includes abstract and vita. Includes bibliographical references (p. 64-73).
14

Optimization of muscle progenitor cell isolation techniques for production of cultivated meat

Steele, Alexandra P January 2023 (has links)
Traditional meat production has major sustainability and ethical concerns. Cultivated meat helps to address these concerns by reducing the need for mass animal farming. Muscle progenitor cells (MPCs) harvested from skeletal muscle are a promising cell source for cultivated meat. While various protocols have been developed for MPC isolation, which protocol is best suited for the cultivated meat industry requires further investigation. Therefore, the purpose of this thesis was to optimize the MPC isolation technique to produce a pure myogenic cell population and provide the cultivated meat industry with standardized procedures for production. For these proof-of-concept experiments, skeletal muscles harvested from the hindlimb muscles of mice were used. Cells were isolated from the harvested muscle then subjected to one of three protocols for MPC enrichment: pre-plating, ice-cold treatment (ICT), or fluorescence activated cell sorting (FACS). The pre-plating and ICT protocols resulted in impure cell populations with few MPCs after one week in culture. Therefore, FACS using two cell-surface markers, NCAM and CD34, was employed as a more specific method for MPC sorting. CD34+NCAM1- cells grew quickly, however, unwanted cell types remained following FACS. In contrast, CD34+NCAM1+ cells had a consistent small, rounded shape and slow proliferation rate. These cells remained viable in culture for several months and had high Pax7 expression, indicating they were a pure population of myogenic cells. CD34+NCAM1+ cells maintained their capacity to differentiate after culturing for an extended period, demonstrating their potential use for cultivated meat production. The results of this study provide a better understanding of the differences between previously published MPC isolation techniques. Future studies will investigate the potential for CD34+NCAM1+ cells to be grown on a larger scale. These experiments provide insight into MPC populations that may exist in livestock species and will help to streamline the early stages of cultivated meat production. / Thesis / Master of Science (MSc) / Traditional meat production is associated with numerous challenges including animal welfare concerns, human health concerns, and harmful environmental consequences. The global population is predicted to reach 9.7 billion by 2050, emphasizing the importance of alternative food sources to meet the increased food demand. Cultivated meat is a promising new protein source, with the intended purpose of providing a sustainable food source with reduced ethical concerns compared to conventional meat. While there are several challenges to overcome throughout the production process, a major consideration in the early stages of cultivated meat production is cell sourcing. Muscle cells harvested from a tissue biopsy are one proposed starting cell source which has the potential to make up most of the tissue in cultivated meat products. This thesis aimed to improve upon previously published protocols used for muscle cell isolation and provide an optimized cell population for use in cultivated meat production. The cell sorting protocol described in this thesis provides a highly efficient technique for muscle cell purification and long-term growth. The resulting cell population has many characteristics that are pertinent to cultivated meat and may advance the early stages of production.
15

Food for two seasons: culinary uses of non-cultivated local vegetables and mushrooms in a south Italian village.

Pieroni, Andrea, Nebel, S., Santoro, R.F., Heinrich, M. 28 October 2009 (has links)
No / The use of non-cultivated plants in a daily diet based on local cuisines is potentially of considerable interest to nutritional scientists, because of the plants' role as local products and their potential as sources of novel nutraceuticals. In many Mediterranean regions these traditions are at risk of disappearing, hence the urgent need to study such knowledge systems. Accordingly, an ethnobotanical survey was carried out among the 850 inhabitants of the village of Castelmezzano, in central Lucania, which is located in the inland southern Italy. Seventy-five taxa of non-cultivated and semi-cultivated local food plants and mushrooms were documented, and uncommon food uses of a few species were reported for the first time. These include Bellavalia romana, Lepista nebularis and Onopordum illyricum. Most of the recorded non-cultivated food plants and mushrooms are cooked in oil or fat. Very few are consumed raw. This article discusses in detail the traditional culinary uses of these plants, their seasonality, ethnoecology, and their economic and nutritional potentials. The article also demonstrates how food agro-biodiversity is inextricably connected with cultural heritage.
16

Selecting donor inbred lines for enhancing the performance of single-cross hybrids from key heterotic groups of oilseed sunflower (Helianthus annuus L.)

Cheres, Mercy Tuiya 28 May 1998 (has links)
Graduation date: 1999
17

Inhibition of anomalous retinal pigment epithelial cell activities, anin vitro study for the effects of 5-fluorouracil and Agaricus bisporuslectin

Cheung, Yiu-him., 張耀謙. January 2012 (has links)
  Proliferative vitreoretinopathy (PVR) remains the major cause of failure of retinal detachment surgery. Retinal pigment epithelial (RPE) cells have been suggested to play a major role in the pathogenesis of PVR. Numerous studies have employed pharmacological means to modulate cellular activities in attempts to inhibit the process. Recent attempts using adjunctive therapy during PVR surgery that consisted of 5-fluorouracil (5-FU) and low molecular weight heparin showed some promise in preventing PVR but the concern is that prolonged 5-FU treatment may have a toxic effect. On the other hand, lectin from the edible mushroom Agaricus bisporus (ABL) was found to inhibit growth of RPE cells in a potent manner without apparent cytotoxicity. This lectin could be a candidate to modulate anomalous proliferation of RPE cells while the mechanism for the observed inhibition is unknown.   In our study, we investigated whether RPE cells treated with 5-FU or ABL would attenuate cellular proliferation, cell migration, cell adhesion and cell-mediated contraction rates. Further, we investigated if complementary inhibition for the above cellular activities could be obtained when RPE cells were treated with ABL after the short treatment using 5-FU. We also explored the possible mechanisms through which ABL inhibited RPE cell proliferation.   ARPE-19 and primary human RPE cells were treated with 5-FU or vehicle for 10 minutes. Cells were then maintained in culture medium supplemented with or without ABL. The rate of cellular proliferation was measured by a tetrazolium salt assay. Effects on cell adhesion were investigated through loading RPE cells onto the strips coated with collagen I or fibronectin. Cell migration was investigated using a scratch wound model. The effect on cell-mediated contraction was assessed using a free floating collagen I matrix. Cytotoxicity of 5-FU and ABL was determined by the live/dead assay.   To elucidate the mechanism through which ABL inhibited RPE cell proliferation, we investigated cell cycle distribution patterns using flow cytometry. Phosphorylation statuses of Erk, Jnk, p38, Akt as well as p53 and Cyclin D expression level were investigated by Western blotting.   Both 5-FU and ABL inhibited RPE cell proliferation. Only ABL promoted cell adhesion towards collagen I in hRPE3 cells. ABL was found to attenuate the rate of cell migration. Cell-mediated collagen gel contraction was attenuated by 5-FU only. Complementary inhibition in cellular proliferation and cell-mediated collagen gel contraction was observed when both 5-FU and ABL were applied. No significant cell death was observed after treatment with 5-FU, ABL or both.   ABL was found to reduce the amount of cells present at S phase. Akt and Erk were found to be hypo-phosphorylated and hyper-phosphorylated respectively after ABL treatment. The expression levels of phosphorylated-Jnk, phosphorylated-p38, p53, and Cyclin D1 were not altered when compared with the control.   These results showed that 5-FU and ABL complement with each other on inhibiting the wound healing activities of RPE cells in vitro without apparent cytotoxicity. They suggested a possible new treatment modality for PVR. ABL hypo-phosphorylated Akt and this observation is in line with the fact that ABL could attenuate cell proliferation. / published_or_final_version / Anatomy / Doctoral / Doctor of Philosophy
18

An archaeobotanical approach to the earliest appearance of domesticated plant species in Ukraine

Motuzaite Matuzeviciute, Giedre January 2010 (has links)
No description available.
19

Analysis of Incentives for Grassland Conversion and Retention in the United State Prairie Pothole Region

Awudu, Lukeman 18 September 2014 (has links)
Over the last century, much of the United State prairie pothole region has been converted to cultivated cropland. Concerns have been raised on government subsidized crop insurance effect on grassland to cropland conversion in the United States. Most grassland in the United State prairie pothole region are privately owned making a vivid understanding of landowners’ response to crop insurance subsidies important to facilitate effective design of prairie pothole conservation programs. The purpose of this study was to determine the extent of land use conversion with the removal of crop insurance subsidies in the United States prairie pothole region. Government subsidies on crop insurance was determined to have a measurable impact on Conservation Reserve Program land acreage within the United States. It was estimated that a 15% reduction in the net returns to cropland resulted in about 274,000 increase in the land acreage of the Conservation Reserve Program. In Conclusion, the removal of crop insurance subsidies was predicted to slow down but not stop the conversion of grassland to cropland in the United States prairie pothole region.
20

A study of a pre-maize cultigen-based subsistence system in the lower Ohio Valley

Snook, J. Carleton January 1974 (has links)
This thesis modifies and enlarges on a theory that a separate center of plant domestication existed in the Lower Ohio Valley prior to the introduction of the Mesoamerican maize, beans, and squash complex. A shift from food-collecting to cultivation occurred around seasonally sedentary foci located along the region's waterways. A model for the development of a pre-maize cultigen-based subsistence system is suggested.This subsistence system provided the basis for the development and evolution of the Scioto Tradition within the Ohio Valley. The thesis questions the applicability of the mud-flat hypothesis to the region under consideration.

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