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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.
121

Submersion

Harper, Hannah M, Ms. 01 May 2014 (has links)
The artist discusses the influence, concept, and process behind creating a cohesive body of work and accompanying show, Submersion, for the completion of her Bachelor of Arts degree and undergraduate research for the Fine and Performing Art Scholars branch of East Tennessee State University's Honors College. The show is to be held May 1st through May 7th of 2014 with its reception on May 3rd in the Submarine Gallery located on ETSU campus. The artist explored themes of the unknown, subconscious, and memory, using water as a reoccurring symbol. The works include five large portraits and two small to medium underwater landscapes in oil paint completed between Fall of 2012 and Spring of 2014. Three large-scale charcoal drawings completed in the Spring of 2013 relate to this body of work as part of a further exploration of the concepts of interest, but will not be included in the Submarine Gallery show and were instead presented as part of the B.A. Senior show in the Fall of 2013. Influences on the artist's work come from artists Jeremy Miranda, Alyssa Monks, Bill Viola, Susanna Majuri, Andreas Franke, and the work and techniques of the Old Masters
122

Climatic Change Causes Abrupt Shifts in Forests, Inferred from a High-resolution Lacustrine Record, Southwestern Quebec, Canada

Paquette, Nathalie 31 October 2012 (has links)
A pollen profile from varved lake sediments sampled at 10-year intervals and spanning the past 1000 years is analyzed to understand the effects of climate change and anthropogenic activity on forests in southwestern Quebec. The forests responded rapidly to changes in temperature and precipitation during the Medieval Warm Period and Little Ice Age as well as to land-use changes associated with the European Settlement of the area. The transition into the Little Ice Age was abrupt and had significant impact on the pollen production within a couple of decades. A synthesis of this record with other high-resolution and well-dated pollen data from the conifer-hardwood forest of eastern North America shows consistent results across the whole area, indicating that very-high resolution pollen data can provide insight into multi-decadal climate variability and its impact on forest vegetation. Tree-ring records from the region show inter-annual fluctuations not always consistent between sites, while high-resolution pollen data record multi-decadal to century changes which enable us to interpret climatic effects on plant communities.
123

Multi-Proxy Approach on Black Carbon Characterization and Combustion Products Source Discrimination in Environmental Media

Kuo, Li-Jung 2009 December 1900 (has links)
Environmental applications of pyrogenic carbon, aka black carbon (BC), have been hampered due to the poor characterization and quantification of environmental BC. This dissertation was dedicated to the better characterization of environmental char/charcoal BC (char-BC), the most heterogeneous and the less identifiable group in the BC continuum. The analytical approach developed for char-BC was further incorporated with other BC methods in environmental samples for a comprehensive assessment of combustion-derived carbon inputs in different environmental systems. The present study firstly evaluated the feasibility of using levoglucosan, a marker derived from cellulose/hemocellulose combustion, to characterize and quantify char-BC in the environment. Levoglucosan was found exclusively in BC materials derived from biomass combustion albeit in highly variable yields across different char-BC. A further examination of synthetic chars showed that temperature is the most influential factor affecting levoglucosan yield in char. Notably, levoglucosan was only detectable in low temperature char samples (150-350 degrees C), regardless of plant species. These results demonstrated that levoglucosan could serve as a good qualitative indicator for the presence of char produced under low temperature conditions in soil, sediments, and aerosols. Results of lignin analysis on the synthetic chars further reveal that combustion can greatly decrease the yield of the eight major lignin phenols with no lignin phenols detected in any synthetic char produced at greater than or equal to 400 degrees C. The values of all lignin parameters show significant shifts with increasing combustion severity (temperature and/or duration), indicating that thermal alteration is an important abiotic lignin degradation process. Hence the input of char-BC in the environments represents a terrestrial organic matter source with highly altered lignin signatures. Finally, a multi-proxy approach, including elemental (soot-BC) and molecular (levoglucosan, polycyclic aromatic hydrocarbons (PAHs), and lignin oxidation products) proxies, was adopted to investigate the centennial-scale temporal distribution of combustion products in four sediment cores from Puget Sound basins, WA. The observed temporal trends of soot-BC and combustion PAHs fluxes reflect the evolution of energy consumption and the positive effects of environmental regulations. The distinct temporal patterns of soot and PAHs among cores demonstrate that urbanization is a crucial factor controlling the inputs of combustion byproducts to the environment. On the other hand, the trends of levoglucosan may be more relevant to the climate oscillation and thus show a regional distribution pattern. Our results demonstrate that environmental loading of combustion byproducts is a complex function of urbanization and land use, fuel usage, combustion technology, environmental policies, and climate changes.
124

TECTONICS & MATERIAL IN THE DESIGN OF A MEDITATION CENTRE IN PEGGY’S COVE, NOVA SCOTIA

Wang, Zhe 22 March 2011 (has links)
Meditation means awareness. It is a process inducing a series of steps, that leads to a state of consciousness which brings serenity and clarity. While the space we choose for meditating needs to reflect the state of clear mind, if possible, it should be isolated from the noisy city and in a natural pure land. This thesis investigates meditation theory and the natural context of Peggy’s Cove, as well as material and tectonic experiments, to design a New Meditation Centre in Peggy’s Cove, Nova Scotia. The design of the New Meditation Center proposes building as a new form of architecture, the form, material and construction of which engages the viewer to admire and respect our nature.
125

Gut microbiome analysis in piglet models infected with Escherchia coli K88: the role of charcoal and dietary crude protein supplemented with probiotic Escherchia coli strains UM2 and UM7.

Meshkibaf, Shahab 08 September 2011 (has links)
Entrotoxigenic Escherichia coli (ETEC) K88 is a causative agent of post-weaning diarrhea (PWD) in early-weaned pigs. This study investigated the efficacy of two alternative diets, charcoal (0.1, 0.5, 1, and 2%) and a low crude protein (CP) diet (17%) supplemented with probiotic E. coli strains (UM2 and UM7), against PWD infection in ETEC K88 challenged piglets. The present study found that charcoal had no effect on the challenged piglets’ performance, ileal and colonic microbiota or their fermentation end products. There was, however, a correlation between charcoal dosage and fecal consistency score. Charcoal reduced the ileal mucosal attached ETEC K88. Feeding a low-CP diet resulted in a lower ileal ammonia concentration. The low-CP diet reduced the E. coli populations in the ileal digesta as well as lowered mRNA expression of the IL-1ß. We concluded that the use of both 1-2% charcoal diet and a low-CP diet supplemented with probiotic E. coli strains were effective in reducing the incidence and severity of PWD infection.
126

Gut microbiome analysis in piglet models infected with Escherchia coli K88: the role of charcoal and dietary crude protein supplemented with probiotic Escherchia coli strains UM2 and UM7.

Meshkibaf, Shahab 08 September 2011 (has links)
Entrotoxigenic Escherichia coli (ETEC) K88 is a causative agent of post-weaning diarrhea (PWD) in early-weaned pigs. This study investigated the efficacy of two alternative diets, charcoal (0.1, 0.5, 1, and 2%) and a low crude protein (CP) diet (17%) supplemented with probiotic E. coli strains (UM2 and UM7), against PWD infection in ETEC K88 challenged piglets. The present study found that charcoal had no effect on the challenged piglets’ performance, ileal and colonic microbiota or their fermentation end products. There was, however, a correlation between charcoal dosage and fecal consistency score. Charcoal reduced the ileal mucosal attached ETEC K88. Feeding a low-CP diet resulted in a lower ileal ammonia concentration. The low-CP diet reduced the E. coli populations in the ileal digesta as well as lowered mRNA expression of the IL-1ß. We concluded that the use of both 1-2% charcoal diet and a low-CP diet supplemented with probiotic E. coli strains were effective in reducing the incidence and severity of PWD infection.
127

Holocene vegetation and fire history of Pender Island, British Columbia, Canada

Lucas, Jennifer D. 30 August 2012 (has links)
Pollen and charcoal analyses were used to reconstruct the Holocene vegetation and fire history of Pender Island (48°46’59” N, 123°18’11” W), located in the southern Gulf Islands on the south coast of British Columbia. A 9.03 m sediment core was retrieved from Roe Lake, a small, deep lake on Pender Island. Four AMS radiocarbon ages, the stratigraphic position of the Mazama tephra and a series of 210Pb ages were used to produce an age-depth model that estimated the base of the sediment core to be 9880 ± 126 calendar years before present (cal yr BP). The vegetation history from Roe Lake is similar to other paleoecological studies from the region. The early Holocene (10,000-7500 cal yr BP) was characterized by mixed woodlands with abundant Pseudotsuga menziesii and a diverse understory that included abundant Salix shrubs and Pteridium aquilinum ferns in these open canopy communities. An open Quercus garryana-dominated community with Acer macrophyllum and Arbutus menziesii in the canopy and xeric associations in the understory occurred from 7500-5500 cal yr BP. By 3500 cal yr BP, modern mixed Pseudotsuga menziesii forests with an increasingly closed canopy were established on Pender Island. Charcoal analyses of the uppermost sediments revealed low charcoal accumulation in the Roe Lake sediment core over the last 1300 years with a mean fire return interval of 100 years for the period before modern fire suppression, suggesting that fire was not a major control on plant community composition on Pender Island on this timescale. Fires were more frequent (i.e., every 47 years on average) during the Medieval Climate Anomaly with warm, dry conditions facilitating a higher fire frequency. Few fires (i.e., every 141 years on average) occurred between 1200-1850 AD, coinciding with the Little Ice Age. As climate was cooler and wetter during the Little Ice Age, fires during this time may reflect intentional burning by First Nations. In general, changes in vegetation and fire dynamics on Pender Island correlate well with changes in climate throughout the Holocene period, suggesting that climate change was likely the principal mechanism driving plant community composition and changes in the fire regime. / Graduate
128

Ancient earth ovens and their environment: a Holocene history of climate, vegetation, and fire in Upper Hat Creek Valley, British Columbia, Canada

Brintnell, Miranda 10 January 2013 (has links)
Paleoecological analyses of an alkaline fen in the southern Interior Plateau of British Columbia, Canada were undertaken in association with ancient earth ovens. Local and regional vegetation and natural disturbance regimes were reconstructed using pollen, plant macrofossils and macroscopic charcoal. At White Rock Springs, Artemisia-Poaceae steppe occurred in the early Holocene and the inferred climate from this period was warmer and drier than present. Increasing moisture at 6000 14C yr BP fostered development of open Pinus ponderosa forests surrounding the fen, with Pinus contorta var. latifolia expanding at higher elevations. A slope-wash event likely resulting from root processing activities occurred in the late Holocene that resulted in 13% Asteraceae Tubuliflorae pollen at 2200 ± 80 14C yr BP. Macroscopic charcoal concentrations increased following this disturbance. Shortly after this time a modern open mixed conifer forest with Pseudotsuga menziesii was likely established. A second major ecological disturbance perhaps occurred within the last 200 years as indicated by fluctuating pollen values of P. ponderosa, Poaceae, Asteraceae Liguliflorae and wetland species. The fen’s vegetation history is consistent with regional records, but rapid changes during the late Holocene apparently occurred in response to disturbances. These disturbances are most likely linked to human root food harvesting and earth oven use, and later to ranching. Differentiation of P. ponderosa and P. contorta pollen types reveals intervals of local forest change that were not detected in previous studies. This study is part of a larger research project at Upper Hat Creek Valley including lithics, phytoliths, and patterns of earth oven structure. / Graduate
129

In vitro studies on the mechanisms of action of chamomile, myrrh and coffee charcoal – components of a traditional herbal medicinal product (Myrrhinil-Intest®)

Vissiennon, Cica 17 February 2015 (has links) (PDF)
The traditional herbal medicinal product Myrrhinil-Intest® is a fixed herbal combination, which is marketed in Germany since 1959 and applied in medical practice for the treatment of gastrointestinal disorders such as functional diarrhea, irritable bowel syndrome and inflammatory bowel disease. It contains myrrh, which is described as the oleo-gum resin from mainly Commiphora molmol Engler (Burseraceae), coffee charcoal, which are the milled roasted to blackening outer seed parts of green dried Coffea Arabica Linné (Rubiaceae) fruits and chamomile flowers - the flower heads of Matricaria recutita Linné (Asteraceae). The clinical effectiveness of Myrrhinil-Intest® for the treatment of various gastrointestinal disorders was demonstrated in several clinical studies and is described in various experience reports, however its pharmacological profile is not fully elucidated. Within the present study the spasmolytic and anti-inflammatory potential of the components myrrh, chamomile and coffee charcoal was investigated. Therefore pharmacological, histological and molecular biological methods were utilised. Spasmolytic activity was characterised using isometric tension measurement with rat isolated small intestinal preparations. Anti-inflammatory potential was assessed with different methods using isolated rat small intestinal preparations and immune cell lines. Inflammation was induced with TNBS and LPS respectively. Additionally, the influence of the herbal components on the gene expression profile of native human macrophages after LPS/IFNγ stimulation was determined by microarray gene expression analysis. Chamomile flower and myrrh exerted spasmolytic effects, whereby the more pronounced spasmolytic effects of myrrh were mediated via calcium channel blockade. Myrrh and chamomile flower exerted anti-inflammatory effects.
130

Pleistocene and Holocene environmental changes in the Brazilian Amazon region

Hermanowski, Barbara 25 February 2013 (has links)
No description available.

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