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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.
101

Student and Intervention Characteristics as Predictors of Response to School Engagement Interventions in the 6th Grade

Brandel, Drew 06 September 2018 (has links)
School engagement has emerged as a consistent target variable in prevention and intervention efforts to improve student achievement and reduce risk of dropout. This dissertation study analyzed several student-level and intervention-level characteristics as potential predictors of student response to school engagement interventions. Participants included 757 6th graders who were a part of a large-scale, comprehensive intervention project for Oregon middle schoolers. The results of the current study indicated that students’ baseline school engagement (as measured by the Student Engagement Instrument), Limited English Proficiency (LEP) Status, and school district significantly predicted response. Implications for research and practice are discussed.
102

Isolation and characterisation of the potential immunomodulatory principles from Astragalus membranaceus

Watson, Robert James January 2006 (has links)
[Abstract]: This thesis describes an in-vivo evaluation of ethanolic extracts of Astragalus membranaceus and fractions derived from this extract administered either orally by gavage or by intraperitoneal injection to Balb/c mice. Total antibody titre was used as an indicator of humoral immune response. Cell mediated immune response was determined using Interferon-γ and Interleukin-12 as indicators. Additionally, mice were vaccinated with a killed Salmonella typhimurium vaccine, previously demonstrated to induce humoral response but not cell mediated immunity, to determine whether the acquired immune response was enhanced or suppressed. Serum was analysed for total antibody titre using an enzyme-linked immunosorbent assay. Serum and splenocyte culture supernatants were analysed for levels of interferon-γ and interleukin-12. No statistically significant differences were observed between groups either orally gavaged or intraperitoneally injected with extracts of Astragalus membranaceus, or orally gavaged with fractions derived from this extract when compared with the control groups.
103

Testing the validity of a non-associative theory of Pavlovian learning, Rate Estimation Theory (RET)

Gean, Emily Grace, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
104

The Evolution of the Carbonate Shelf Margins and Fill of the Antler Foreland Basin by Prograding Mississippian Carbonates, Northern U.S. Rockies

Buoniconti, Matthew Robert 09 December 2008 (has links)
The aims of this study are to extend the established high-resolution sequence stratigraphic framework of the Madison Formation of Wyoming and southern central Montana to the correlative and genetically-related Mississippian carbonate ramp, ramp margin, and basin strata of the central Montana trough and Antler foreland basin in order to examine and discriminate the controls on depositional processes and the resulting stratigraphic architecture through space and time in tectonically-active settings. An outcrop-based, high-resolution sequence stratigraphic study of two ramp-to-basin transects, one in central Montana and the other in southwestern Montana and east-central Idaho, is conducted in order to examine these deposits across two coeval margins with differing subsidence, hydrodynamic, and physiographic configurations and histories. Independent measurements of system response to global and local forcings allows disentanglement of primary controls on deposition and allows us to gain understanding of the roles and interplay of these controls, in particular eustasy and tectonics, on the system's architectural development. Conversely, insight into the geodynamic evolution of western North America, glacioeustatic changes, and variations in global climate and oceanographic systems during the greenhouse-to-icehouse transition is gained. A series of high-resolution sequence stratigraphic cross-sections and time-slices are produced incorporating outcrop measured sections and measured sections previously collected by members of the Comparative Sedimentology Laboratory in a series of transects across the Madison ramp system. A new chronostratigraphic framework for Madison carbonates is developed by using Lower Carboniferous delta C-13 isotope excursions as isochronous tie points between ramp-top, margin, and basinal sections. These delta C-13 excursion events have been documented to be time-invariant globally due to global changes in ocean chemistry. The results of the study include resolution and discrimination of sequential foreland basin subsidence, carbonate sediment production and progradation, subsidence and uplift of foreland basin structures along a carbonate shelf edge, diachronous subsidence of discrete depocenters, and eustasy.
105

Characterization of the DNA Damage Resistance Gene RTT107

Roberts, Tania 28 July 2008 (has links)
In Saccharomyces cerevisiae, RTT107 (ESC4, YHR154W) encodes a BRCT-domain protein that is important for recovery from DNA damage during S phase. I have found that Rtt107 forms a complex with the Slx1/Slx4 structure-specific nuclease. Deletion of SLX4 confers many of the same phenotypes observed in rtt107∆, including DNA damage sensitivity, prolonged DNA damage checkpoint activation, and increased spontaneous DNA damage, suggesting that Slx4 and Rtt107 function in concert. These defects are not shared by Slx1 indicating that the function of Slx4 and Slx1 in the DNA damage response is not entirely overlapping. Furthermore, I found that Slx4 regulates the phosphorylation of Rtt107 by the checkpoint kinase Mec1. The phenotypes conferred by deletion of RTT107 and the spectrum of its synthetic genetic interactions indicates that Rtt107 may function at stalled replication forks. I have shown that Rtt107 is recruited to chromatin in the presence of DNA damaging agents that cause DNA replication forks to stall. Recruitment of Rtt107 to chromatin requires Rtt109, an acetyltransferase, and the cullin Rtt101, but is not dependent on Slx4 or the checkpoint kinases. Rtt109 acetylates histone H3 on lysine 56 (H3-K56), yet recruitment of Rtt107 to chromatin does not require acetylation of H3-K56, indicating that Rtt109 may have additional targets. Chromatin immunoprecipitation indicates that the sites of Rtt107 binding correspond to regions at or near stalled replication forks throughout the genome. I propose that Rtt107 acts in the recovery from DNA damage by localizing to stalled replication forks and acting as a scaffold for assembly of DNA damage response proteins, ultimately promoting replication fork restart.
106

Characterization of the DNA Damage Resistance Gene RTT107

Roberts, Tania 28 July 2008 (has links)
In Saccharomyces cerevisiae, RTT107 (ESC4, YHR154W) encodes a BRCT-domain protein that is important for recovery from DNA damage during S phase. I have found that Rtt107 forms a complex with the Slx1/Slx4 structure-specific nuclease. Deletion of SLX4 confers many of the same phenotypes observed in rtt107∆, including DNA damage sensitivity, prolonged DNA damage checkpoint activation, and increased spontaneous DNA damage, suggesting that Slx4 and Rtt107 function in concert. These defects are not shared by Slx1 indicating that the function of Slx4 and Slx1 in the DNA damage response is not entirely overlapping. Furthermore, I found that Slx4 regulates the phosphorylation of Rtt107 by the checkpoint kinase Mec1. The phenotypes conferred by deletion of RTT107 and the spectrum of its synthetic genetic interactions indicates that Rtt107 may function at stalled replication forks. I have shown that Rtt107 is recruited to chromatin in the presence of DNA damaging agents that cause DNA replication forks to stall. Recruitment of Rtt107 to chromatin requires Rtt109, an acetyltransferase, and the cullin Rtt101, but is not dependent on Slx4 or the checkpoint kinases. Rtt109 acetylates histone H3 on lysine 56 (H3-K56), yet recruitment of Rtt107 to chromatin does not require acetylation of H3-K56, indicating that Rtt109 may have additional targets. Chromatin immunoprecipitation indicates that the sites of Rtt107 binding correspond to regions at or near stalled replication forks throughout the genome. I propose that Rtt107 acts in the recovery from DNA damage by localizing to stalled replication forks and acting as a scaffold for assembly of DNA damage response proteins, ultimately promoting replication fork restart.
107

Singing Ourselves In

King, Anna-Leah 22 October 2007
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.
108

Combined Micro and Nanopatterning for Cell Substrates

Eliason, Marcus Todd 09 April 2007 (has links)
The success of many emerging biotechnologies depends upon the ability to tune cell function to mimic conditions found in vivo. Cells exhibit complex interactions with their surrounding environment known and the extracellular matrix (ECM). These interactions control many cell functions such as proliferation, differentiation and cell death. ECM components span the meso-, micro- and nano-length scales. Successful biotechnologies therefore must also exhibit patterning over these length scales. The objective of this study is to fabricate and analyze cell response to micro and nanopatterned polymer substrates. Experiments examined cell alignment and proliferation to various substrates. The substrates used featured micropatterned grooves and holes, micropatterned carbon nanotubes, and combinations of microgrooves and nanogrooves. Results showed significant interactions between cell alignment and the patterned topography for all substrate types, while cell proliferation showed no significant dependence on these topographic parameters.
109

Observational and numerical study of Atlantic tropical instability waves

Wu, Qiaoyan 02 June 2009 (has links)
This study uses high resolution satellite measurements from the Tropical Rainfall Measuring Mission (TRMM), Quick Scatterometer (QuikSCAT) and Special Sensor Mi¬crowave Imager (SSM/I) to investigate the variability of sea surface temperature (SST), surface wind velocity, water vapor, cloud liquid water and precipitation associated with westward moving tropical instability waves (TIWs) in the Atlantic Ocean from 1998 to 2005. On interannual scales, TIWs in the Pacific Ocean are strongest during the cold phase of El Ni¨ no Southern Oscillation (ENSO), when the cold tongue is most pronounced. The waves are weak during the warm phase of ENSO. A low-frequency Atlantic air-sea cou-pled mode influences the TIW activity in the Atlantic Ocean as ENSO does in the Pacific Ocean. The characteristics of TIWs are largely associated with the background oceano-graphic states. Coherent ocean-atmosphere patterns are shown in the Atlantic Ocean during eight years. Southeasterly trades strengthen and water vapor increases over warm SST anomalies associated with TIWs. The opposite is true over cold TIW SST anomalies. The cloud liquid water and rain response to the SST follows a very similar pattern, appearing to be roughly in phase with wind convergence and divergence in the central tropical Atlantic. The atmospheric response to the TIW SST anomalies extends north of the TIW active region, suggesting a remote response to the TIWs. The atmospheric response to the Atlantic TIWs shows interannual variability. In 1999, the rainfall response to the TIW SST anomalies is much larger than in other years, which is due to the southward movement of Atlantic ITCZ (Intertropical Convergence Zone). When the Atlantic ITCZ moves south, it is more susceptible to TIW influence. One regional climate model and one global climate model are applied to study the mechanism of atmospheric response to the Atlantic TIWs with daily TMI satellite SST forcing. Both models successfully simulated the wind velocity, wind convergence and pre-cipitation as observed. While the satellite observations support the vertical mixing mech-anism for the surface wind response to TIWs, both models show the pressure gradient mechanism is dominant in the Atlantic.
110

Development of Parameterized Surge Response Functions for Coastal Bays

Katyal, Rajat 2009 December 1900 (has links)
In the past few years, there has been an increase in the number of hurricanes hitting the Gulf of Mexico coastline. These hurricanes have caused damage in the billions of dollars, and hundreds of people have been killed during these events. The damage from hurricanes is caused by four main factors: storm surges, waves, strong winds and rain. At the coast, the damage due to the storm surge and waves is dominant. Numerical simulation models like ADCIRC are available for estimating storm surge, but high computational time makes it impossible to use them for evacuation planning purposes. Public perception of storm surge hazard is based upon the Saffir Simpson scale. As demonstrated by Hurricanes Katrina and Ike, the Saffir Simpson scale does not work well for surge prediction. The accurate and timely prediction of storm surge is very important. For this purpose, dimensionless Surge Response Functions (SRFs) for the open coast of Texas has been developed (Irish et.al 2008a and Song, 2009). The surge inside bays tends to be different from that at the open coast due to local geometric factors like shape, center of gravity, and characteristic size of the bay. To predict accurately the surge levels inside the bay, scaling laws are developed based upon the above mentioned factors. These scaling laws are used along with SRFs for the open coast (Irish et. al. 2009) to develop dimensionless SRFs for bays. The SRFs for 3 bays, Matagorda, Galveston and Corpus Christi have been explored. Results have shown that the Surge Response method works reasonably well for Matagorda, Corpus Christi and Galveston Bay. For these bays the dimensionless surge lies within the 95% confidence interval of Surge Response Functions.

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