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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.
501

Singing ourselves in

King, Anna-Leah 03 December 2007 (has links)
In a qualitative study, grade three students in an urban classroom were introduced to Aboriginal children's picture-storybooks followed by "menoh," which are literary response activities. "Menoh" is defined as aesthetics, although, in this study "menoh" activities stem from Anishnabe and Cree cultural ways such as in traditional singing, dance, drumming, art and cooking.<p> The researcher used a reframing as a decolonizing methodology in order to reclaim Aboriginal voice and perspective. Reframing is taking greater control over the way Aboriginal research is structured, analyzed and written. The research data was collected over a period of several months within the classroom where the researcher read aloud and drew Aboriginal and non-Aboriginal listeners into the multi-layers of the stories. Through dialogue and critique, the students discussed the stories in literary circles. They shared meanings about the stories and made connections to their own lives and the lives of others. The stories contained messages about loyalty, respect, responsibility, honesty, humility, trust, and sharing-all those qualities that helped Aboriginal people live the life they did and still do today. Discussion was followed by a variety of "menoh," activities that introduced aesthetic ways of knowing from an Aboriginal perspective.
502

Variation of Feeding Regimes: Effects on Giant Panda (Ailuropoda melanoleuca) Behavior

Sandhaus, Estelle Ann 03 December 2004 (has links)
Giant pandas in captivity are typically fed discrete amounts of highly concentrated food on a fixed time schedule, in addition to limited amounts of fresh bamboo throughout the day. In response to informal observations that these animals engage in a number of undesirable behaviors just prior to the predictable feeding of concentrated meals, we examined the existing feeding regime at the Research Base of Giant Panda Breeding in Chengdu, Peoples Republic of China. We sought to determine whether undesirable behaviors were occurring more frequently before the delivery of meals than at other times of day and whether modified feeding regimes would result in a more species-appropriate activity budget overall. As predicted, female giant pandas spent significantly more time engaged in door-directed/human-oriented behavior, stereotypic behavior, and non-stereotypic locomotion in the 30-minute periods prior to the feeding of concentrated meals. When placed on a modified feeding schedule in which frequency of bamboo provisioning was increased (total amount was held constant), significant differences were not found between study phases for the above-mentioned behaviors of interest, though a visual trend towards a decline in stereotypic behavior during the experimental phase was noted. Male pandas, when placed on a less predictable feeding schedule, did not exhibit significant behavioral differences in behaviors of interest between experimental phases or observation periods. These findings may be attributable in part to the low power inherent in the small sample size. However, visual trends that may be indicative of feeding anticipatory activity (FAA) were apparent. It appears that giant pandas, like many other animal species cited in the literature, are sensitive to periodic feeding regimes, though it is less clear as to which regime modifications will prove most beneficial.
503

Influences of Firework Displays on Ambient Air Quality during the Lantern Festival in Kaohsiung City

Chien, Li-hsing 10 August 2010 (has links)
In recent years, the celebration activities of various types of folk-custom festivals in Taiwan have already been getting more and more attention from civilians. Festivities throughout the whole island are traditionally accompanied by loud and brightly colored firework displays. Among these activities, the firework display during the Chinese Lantern Festival in Kaohsiung City is one of the largest festivals in Taiwan every year. Therefore, it is important to investigate the influences of firework displays on ambient air quality during the Chinese Lantern Festival in Kaohsiung City. Field measurement of ambient gaseous pollutants and particulate matter (PM) was conducted on February 9-12, 2009, the Chinese Lantern Festival, in Kaohsiung City. Moreover, three kinds of firework powders obtained from the same factory producing Kaohsiung Lantern Festival fireworks were burned in a combustion chamber to determine the physicochemical properties of firework aerosols. Metallic elements were analyzed with an inductively coupled plasma-atomic emission spectrometer (ICP-AES). Ionic species and carbonaceous contents in the PM samples were analyzed with an ion chromatography (IC) and an elemental analyzer (EA), respectively. Finally, the source identification and apportionment of PM were analyzed by principal component analysis (PCA), enrichment factor (EF), and receptor modeling (CMB). For inorganic gaseous pollutants, the concentration peaks of NO, NO2, O3, CO were observed during the firework periods, and the concentration peak of NO was approximately 8.8 times higher than those during the non-firework periods. This study further revealed that, even at nighttime, ambient O3 could be reduced dramatically during the firework periods, whenas NO2 concentration increased concurrently, due to titration effects resulting from the prompt reaction of NO with O3 to form NO2 and O2. For organic gaseous pollutants, the concentration peak of toluene during the firework periods was approximately 2.2-4.1 times higher than those during the non-firework periods. Several metallic elements of PM during the firework display periods were obviously higher than those during the non-firework periods. On February 10, the concentrations of Mg, K, Pb, and Sr in PM2.5 were 10 times higher than those during the non-firework periods. Besides, the Cl-/Na+ ratio was slightly smaller than 1 in Kaohsiung Harbor, but it was approximately 3 during the firework display periods since Cl- came form chlorine content in firework aerosols at this time. Moreover, OC/EC ratio increased up to 2.8. In addition to the analysis of gaseous pollutants and PM during the Chinese Lantern Festival in Kaohsiung City, this study burned firework powders in a self-designed combustion chamber to measure the physicochemical properties of firework aerosols. In the results, K, Mg, Cl-, OC were major contents (<10%) in the aerosols produced from the burning firework powders. Moreover, Cl-/Na+ and OC/EC ratio were 15.0~23.4 and 2.9~3.2, respectively. Consequently, Cl-/Na+ and OC/EC ratio can be used as two important indicators of firework displays. Results obtained from PCA and CMB receptor modeling showed that the major sources of aerosols during the firework display periods were firework displays, motor/diesel vehicle exhanst, soil dusts, and marine aerosols. Besides, the firework displays on February 10 contributed approximately 25.2% and 16.6% of PM10 at two sampling sites, respectively.
504

Diurnal Variation of Atmospheric Particles and their Source Fingerprint at Xiamen Bay

Wu, Chung-Yi 31 August 2011 (has links)
In recent years, the rapid development of economy and industry in Xiamen Bay causes serious environmental problems, particularly poor air quality and visibility impairment. There are no large-scale industrial emission sources in Kinmen Island, however, its ambient air quality is always the poorest in Taiwan. Moreover, ambient air quality monitoring data showed that PM10 concentrations varied in daytime and at nighttime. Consequently, this study tired to ascertain the potential causes for this phenomenon. This study selected ten particulate matter (PM) sampling sites at Xiamen Bay, including five sites at Kinmen Island and five sites at metro Xiamen. Particulate matter sampling was conducted in daytime (8:00-17:00) and at nighttime (17:00-8:00), which included regular and intensive sampling. Regular sampling was conducted to collect PM10 with high-volume samplers three times a month from April 2009 to April 2010, while intensive sampling was conducted to collect fine (PM2.5) and coarse (PM2.5-10) particles with dichotomous samplers and particle size distribution with a MOUDI at site B2 for consecutive 5 days in the spring and winter of 2009~2010. After sampling, the physicochemical properties of PM, including mass concentrations, particle size distribution, water- soluble ionic species, metallic elements, and carbonaceous contents were further analyzed. The level of atmospheric PM is affected by meteorological condition, thus PM10 concentrations in winter and fall was much higher than those in spring and summer. Results from backward trajectories showed that the concentrations of PM10 blown from the north were generally higher than those from the south. Furthermore, t-test analysis indicated that PM10 concentrations in daytime and at nighttime at site B3 were significantly different (p-value<0.05). During the intensive sampling periods, PM10 concentrations were mainly affected by coarse particles compared to fine particles. The highest concentration for fine and coarse particle modes occurred at the size ranges of 0.32~0.56 £gm and 3.2~5.6 £gm, respectively. The most abundant water-soluble ionic species of PM10 were secondary inorganic aerosols (SO42-, NO3-, and NH4+) which accounted for 85% of total ions. The daytime and nighttime PM10 concentration ratios (D/N) for Mg, K, Ca, Cr, Mn, Fe, Zn, Al, Cu, As, and V were in the same order of magnitude, however, the D/N ratios of Cd, Pb, Ni, and Ti in spring and summer varied higher than an order of magnitude, indicating that the emission sources of PM were different in daytime and at nighttime. Correlation analysis of OC and EC showed that OC and EC at nighttime had a higher correlation than those in daytime, while OC and EC had a higher correlation in Kinmen Island than those in metro Xiamen, indicating carbonaceous sources must be different in summer and winter at Xiamen Bay. Enrichment factor analysis revealed that ceramic industry, stone processing, and cement industry had higher correlation with PM10 concentration than utility power plants. Crustal dusts consisted of road dusts, farmland dusts, and constructive dusts, while biomass burning was not a negligible sources. Results obtained from PCA and CMB receptor modeling showed that major sources of PM in Xiamen Bay were secondary inorganic aerosols, fuel and biomass burning, marine aerosols, vehicular exhansts, and soil dusts. Besides, stone processing, cement industry, ceramic industry, and utility power plants had the highest contribution in winter. Their contributions in daytime and at nighttime were 38% and 45%, respectively.
505

The Effect Of Self-esteem Enrichment Bibliocounseling Program On The Self-esteem Level Sixth Grade Students

Karacan, Nurten 01 September 2009 (has links) (PDF)
This study aims to design and investigate the effect of Self-Esteem Enrichment Bibliocounseling Program on the self-esteem level of sixth grade students. Twenty four subjects (13 female, 11 male) out of 166 total sixth grade students from a university affiliated private middle school in Ankara, were randomly selected based on Coopersmith Self-Esteem Inventory (CSEI) total scores and assigned to treatment and no-treatment control group conditions. An experimental design with one selfesteem treatment group and one no-treatment control group, and two measurements (pre and post) were used to investigate the effectiveness of Self-Esteem Enrichment Bibliocounseling Program. The treatment program developed by the researcher was introduced to subjects during eight weeks. The group sessions were held once a week. Each session lasted 80 minutes. Mixed Design (one between and one within factor) Repeated-Measures Analysis of Variance (ANOVA) was employed to the pre-test and post-test CSEI scores of experimental and control group subjects. Results indicated that, the Self-Esteem Enrichment Bibliocounseling Program employed to the treatment group produced significant increase in treatment group subjects self-esteem scores.
506

Electrokinetic focusing of charged species at bipolar electrode in a microfluidic device

Perdue, Robbyn K. 14 February 2012 (has links)
The development and characterization of bipolar electrode (BPE) focusing is described. BPE focusing is an electrokinetic equilibrium technique in which charged analytes are focused and locally enriched on an electric field gradient in the presence of a counter-flow. This electric field gradient is formed at the boundary of an ion depletion zone – the direct result of faradaic reactions occurring at the BPE in the presence of an externally applied electric field. Direct measurement of the electric field strength in the ion depletion region shows that the electric field is enhanced in this region and takes on a gradient shape, confirming the results of numerical simulations. Transient electric field measurements with simultaneous monitoring of a focused fluorescent tracer reveal that the field gradient forms rapidly upon application of the external field and remains stable over time with the tracer focused at a local field strength predicted by simple electrokinetic equations. These transient electric field measurements probe the effect of individual experimental parameters on the electric field gradient and the focused band. The results of these studies indicate that a steeper field gradient leads to enhanced concentration enrichment of the analyte. The slope of the gradient is increased with higher concentration of the running buffer and higher applied field strength. The addition of pressure driven flow across the microchannel moves the location of the field gradient and the position of the focused band. Further enhancement of enrichment is achieved through the suppression of Taylor dispersion after coating the microchannel with a non-ionic surfactant. The findings of these studies have motivated the transition of BPE focusing to smaller microchannels. A decrease in microchannel size not only decreases Taylor dispersion, but also provides access to higher buffer concentration and higher applied field strength, both of which enhance enrichment. The result is a three-order-of-magnitude increase in total analyte enrichment at a much higher enrichment rate. Furthermore, a dual channel configuration for BPE focusing is introduced which provides greater control over focusing conditions. Finally, the formation of ion depletion and enrichment zones at a BPE in a microchannel is shown to mimic ion concentration polarization (ICP) at micro-/nano-channel junctions. This is significant because this faradaic ICP provides a model to which traditional ICP can be compared and is achieved in a more easily fabricated device. In summary, the fundamental principles of BPE focusing are described. A greater understanding of the effect of experimental parameters on the focusing process leads to an unprecedented magnitude and rate of enrichment in a simple device architecture. / text
507

The Effect of Extra Food Stimulation on Asian Elephants (Elephas maximus) Kept at Kolmården Zoo

Sjöberg, Johanna January 2011 (has links)
Stereotypic behaviors in all animals are more often than not associated with poor welfare. Limited access to perform species specific behaviors is often a reason for the development of stereotypies. Elephants with their great intelligence and need of social contact, coupled with a destructive a behavior are especially difficult to house in captivity. To decrease the occurrence of stereotypic behaviors in elephants, environmental enrichment in form of food enrichment is a good option, since elephants have a great need of foraging. The aim of this study was to investigate if an extra supply of food enrichment could decrease the presence of stereotypic behaviors at night in three Asian elephants at Kolmården zoo. Already existing hay nets attached to wires in the roof were used and connected to a timer. The hay nets were lowered to vision trunk reach between 6:00 am and 6:30 am during five days and the frequencies of selected behaviors were compared with the frequencies of the same behaviors during five preceding baseline nights. The animals were filmed using mounted cameras with IR lights. There was a significant decrease of stereotypic behavior for one of the elephants, but all three showed an increase in foraging whereof the increases were significant for two of them. One of the elephants showed no stereotypic behaviors at all during the study. To keep in mind is that the elephants have different backgrounds and experiences which might have influenced the results.
508

Two Novel Methods for Clustering Short Time-Course Gene Expression Profiles

2014 January 1900 (has links)
As genes with similar expression pattern are very likely having the same biological function, cluster analysis becomes an important tool to understand and predict gene functions from gene expression profi les. In many situations, each gene expression profi le only contains a few data points. Directly applying traditional clustering algorithms to such short gene expression profi les does not yield satisfactory results. Developing clustering algorithms for short gene expression profi les is necessary. In this thesis, two novel methods are developed for clustering short gene expression pro files. The fi rst method, called the network-based clustering method, deals with the defect of short gene expression profi les by generating a gene co-expression network using conditional mutual information (CMI), which measures the non-linear relationship between two genes, as well as considering indirect gene relationships in the presence of other genes. The network-based clustering method consists of two steps. A gene co-expression network is firstly constructed from short gene expression profi les using a path consistency algorithm (PCA) based on the CMI between genes. Then, a gene functional module is identi ed in terms of cluster cohesiveness. The network-based clustering method is evaluated on 10 large scale Arabidopsis thaliana short time-course gene expression profi le datasets in terms of gene ontology (GO) enrichment analysis, and compared with an existing method called Clustering with Over-lapping Neighbourhood Expansion (ClusterONE). Gene functional modules identi ed by the network-based clustering method for 10 datasets returns target GO p-values as low as 10-24, whereas the original ClusterONE yields insigni cant results. In order to more speci cally cluster gene expression profi les, a second clustering method, namely the protein-protein interaction (PPI) integrated clustering method, is developed. It is designed for clustering short gene expression profi les by integrating gene expression profi le patterns and curated PPI data. The method consists of the three following steps: (1) generate a number of prede ned profi le patterns according to the number of data points in the profi les and assign each gene to the prede fined profi le to which its expression profi le is the most similar; (2) integrate curated PPI data to refi ne the initial clustering result from (1); (3) combine the similar clusters from (2) to gradually reduce cluster numbers by a hierarchical clustering method. The PPI-integrated clustering method is evaluated on 10 large scale A. thaliana datasets using GO enrichment analysis, and by comparison with an existing method called Short Time-series Expression Miner (STEM). Target gene functional clusters identi ed by the PPI-integrated clustering method for 10 datasets returns GO p-values as low as 10-62, whereas STEM returns GO p-values as low as 10-38. In addition to the method development, obtained clusters by two proposed methods are further analyzed to identify cross-talk genes under fi ve stress conditions in root and shoot tissues. A list of potential abiotic stress tolerant genes are found.
509

Towards a plant-based method of guiding CO₂ enrichment in greenhouse tomato

Edwards, Diane Roselyn 05 1900 (has links)
Atmospheric CO₂ enrichment is employed by greenhouse tomato growers to increase fruit yields, and CO₂ applications are managed according to atmospheric set points or CO₂ injection rates. These methods do not immediately focus on the targets of CO₂ applications: plant performance and the regulation of plant carbon status. This thesis explores several plant-based approaches that may have potential for use in the management of CO₂ in greenhouse tomato production. Three plant-based approaches to CO₂ management were explored in commercial and experimental tomato greenhouses. These were: (1) simulation modeling, (2) non-destructive analysis of growth and (3) the status of plant carbon reserves. A cost and benefit analysis (c/b) using simulation modeling was carried out using grower-collected greenhouse environment and yield data. Simulation modeling was useful for retrospectively determining c/b of several CO₂ scenarios. The model was effective in predicting long term yields, but not short term yield variations, which limits its application for CO₂ management. Non-destructive measures of growth: stem length and diameter, leaf area and fruit load were found to be too sluggish for daily CO₂ dosing decision-making. Finally, plants growing under CO₂ enrichment can deposit substantial carbon as starch in their leaves. Plant carbon status was evaluated by determining the spatial distribution of leaf starch in the shoot and by following its variation diurnally and after the onset of CO₂ enrichment. As starch is difficult to measure by a grower, leaf mass per unit area (LMA) was also monitored for assessment as a surrogate measure for starch. Leaves in positions 7 to 9 were identified as the most meaningful in the shoot to sample. Diurnal profiles indicated these leaves carryover substantial starch from one day to the next. Monitoring starch at its peak time of accumulation (14 h to 16 h), at sunset and sunrise will indicate how much the peak starch reserves are used overnight. If starch remains high between peak and sunrise the following day, then the plants are in a carbon-surplus state and CO₂ enrichment could be postponed. For upper canopy leaves LMA is substantially influenced by starch and thus is a promising surrogate.
510

Identification of bacterial pathogenic gene classes subject to diversifying selection

Sumir Panji January 2009 (has links)
<p>Availability of genome sequences for numerous bacterial species comprising of different bacterial strains allows elucidation of species and strain specific adaptations that facilitate their survival in widely fluctuating micro-environments and enhance their pathogenic potential. Different bacterial species use different strategies in their pathogenesis and the pathogenic potential of a bacterial species is dependent on its genomic complement of virulence factors. A bacterial virulence factor, within the context of this study, is defined as any endogenous protein product encoded by a gene that aids in the adhesion, invasion, colonization, persistence and pathogenesis of a bacterium within a host. Anecdotal evidence suggests that bacterial virulence genes are undergoing diversifying evolution to counteract the rapid adaptability of its host&rsquo / s immune defences. Genome sequences of pathogenic bacterial species and strains provide unique opportunities to study the action of diversifying selection operating on different classes of bacterial genes.</p>

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