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4-Ethoxymethylphenol: a novel phytoestrogen that acts as an agonist for human estrogen receptors.
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Date: December 2001
Creator: Pearce, Virginia
Description: Estrogen is the natural agonist of the estrogen receptor (ER). However, certain plant-derived compounds or phytoestrogens have been identified that mimic estrogens and act as agonists and/or antagonists of ERs, depending on subtype and target tissue. Understanding how phytoestrogens interact with ERs, and therefore effect the estrogenic response, may prove beneficial in hormone replacement therapy and in the prevention and treatment of hormone-related diseases. Using Thin Layer Chromatography, gas chromatography/mass spectrometry (GC/MS), and proton nuclear nagnetic resonance (HNMR), I identified 4-ethoxymethylphenol (4EM) found in Maclura pomifera. While most phytoestrogens are heterocyclic compounds, 4EM is a simple phenol that acts as an agonist of ER-alpha and -beta in HeLa and MCF-7 cells. To study the effect of 4EM on ER-alpha and -beta activity, I performed transient transfection assays and showed that 4EM activates ER dependent gene transcription in a dose dependent manner in both ER subtypes. Further, 4EM- mediated transcription in ER-alpha, like estrogen, was enhance in the presense of co-activators, SRC-1 (steroid receptor coactivator-1), CBP (CREB binding proteins), and E6-AP (E6-associated protein) and inhibited by trans-4- hydroxytamoxifen (4HT). I found that 4EM was specific for ER and did not activate transcription of the progesterone receptor in HeLa cells.
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9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress
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Date: May 2012
Creator: Nalam, Vamsi J.
Description: The activity of plant 9-lipoxygenases (LOXs) influences the outcome of Arabidopsis thaliana interaction with pathogen and insects. Evidence provided here indicates that in Arabidopsis, 9-LOXs facilitate infestation by Myzus persicae, commonly known as the green peach aphid (GPA), a sap-sucking insect, and infection by the fungal pathogen Fusarium graminearum. in comparison to the wild-type plant, lox5 mutants, which are deficient in a 9-lipoxygenase, GPA population was smaller and the insect spent less time feeding from sieve elements and xylem, thus resulting in reduced water content and fecundity of GPA. LOX5 expression is induced rapidly in roots of GPA-infested plants. This increase in LOX5 expression is paralleled by an increase in LOX5-synthesized oxylipins in the root and petiole exudates of GPA-infested plants. Micrografting experiments demonstrated that GPA population size was smaller on plants in which the roots were of the lox5 mutant genotype. Exogenous treatment of lox5 mutant roots with 9-hydroxyoctadecanoic acid restored water content and population size of GPA on lox5 mutants. Together, these results suggest that LOX5 genotype in roots is critical for facilitating insect infestation of Arabidopsis. in Arabidopsis, 9-LOX function is also required for facilitating infection by F. graminearum, which is a leading cause of Fusarium head ...
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Academic Dishonesty: Attitudes and Behaviors of Fundamentalist Christian College Students
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Date: December 2000
Creator: Sunday, William G.
Description: This study was designed to examine: (1) the extent to which cheating occurs in fundamentalist Christian colleges; (2) the attitudes of fundamentalist Christian college students toward cheating; (3) attitudes of fundamentalist Christian college students toward cheating among their peers; (4) the kinds of cheating practices of fundamentalist Christian college students; (5) the degree to which students engage in neutralizing behavior to justify cheating; (6) differences in cheating behaviors according to gender; (7) differences in cheating behaviors according to ethnicity; and (8) differences in cheating behaviors according to the length of duration of Christian commitment. Based upon the responses of 337 students attending 3 different Christian colleges, it was concluded that: (1) most Christian fundamentalist students do not engage in cheating; (2) respondents believe that each of 17 self-reported cheating behaviors are serious forms of cheating; (3) respondents are unlikely to report cheating among peers; (4) plagiarism is the most common cheating behavior; (5) most respondents justify cheating on the basis of the workload at school and the pressure to obtain good grades; (6) there are no differences in cheating behavior according to gender; (7) there are differences in cheating behavior according to groups; and (8) most respondents do not cheat ...
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African Refugee Parents' Involvement in Their Children's Schools: Barriers and Recommendations for Improvement
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Date: December 2009
Creator: Githembe, Purity Kanini
Description: The purpose of this study was to examine involvement of African refugee parents in the education of their elementary school children. The setting of the study was Northern and Southern Texas. African refugee parents and their children's teachers completed written surveys and also participated in interviews. In the study's mixed-method design, quantitative measures provided data about parent involvement at home, parent involvement at school, frequency of parent-teacher contact, quality of parent-teacher relationship, parent endorsement of children's schools, and barriers to parent involvement. Qualitative data from the open-ended questions provided data on barriers and strategies to improve involvement. Sixty-one African refugee parents responded to the survey and also participated in an in-depth face-to-face or telephone interview. Twenty teacher participants responded to an online survey. Quantitative data gathered from the parent and teacher surveys were analyzed using frequency distributions and analyses of variance. Qualitative data were analyzed by summarizing and sorting information into different categories using Weft QDA, an open-source qualitative analysis software. From these data, I identified barriers to African refugee parent involvement in their children's schools, as well as challenges that teachers face as they try to involve African refugee parents. Results of analyses of variance revealed statistically significant differences ...
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The Afro-British Slave Narrative: The Rhetoric of Freedom in the Kairos of Abolition
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Date: December 1999
Creator: Evans, Dennis F.
Description: The dissertation argues that the development of the British abolition movement was based on the abolitionists' perception that their actions were kairotic; they attempted to shape their own kairos by taking temporal events and reinterpreting them to construct a kairotic process that led to a perceived fulfillment: abolition. Thus, the dissertation examines the rhetorical strategies used by white abolitionists to construct an abolitionist kairos that was designed to produce salvation for white Britons more than it was to help free blacks. The dissertation especially examines the three major texts produced by black persons living in England during the late eighteenth centuryIgnatius Sancho's Letters of the Late Ignatius Sancho (1782), Ottobauh Cugoano's Thoughts and Sentiments on the Evil of Slavery (1787), and Olaudah Equiano's The Interesting Narrative of the Life of Olaudah Equiano, or Gustavus Vassa, the African (1789)to illustrate how black rhetoric was appropriated by whites to fulfill their own kairotic desires. By examining the rhetorical strategies employed in both white and black rhetorics, the dissertation illustrates how the abolitionists thought the movement was shaped by, and how they were shaping the movement through, kairotic time. While the dissertation contends that the abolition movement was rhetorically designed to provide redemption, ...
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Age-Dependent Effects Of Chronic GABAA Receptor Blockade In Barrel Cortex
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Date: May 2001
Creator: Gargan, Lynn
Description: GABAA receptor binding is transiently increased in rat whisker barrels during the second postnatal week, at a time when neurons in the developing rat cortex are vulnerable to excitotoxic effects. To test whether these GABAA receptors might serve to protect neurons from excessive excitatory input, polymer implants containing the GABAA receptor antagonist bicuculline were placed over barrel cortex for a 4-day period in young (postnatal days 8 - 12) and adult rats. In the cortex of young, but not adult rats, the chronic blockade of GABAA receptors resulted in substantial tissue loss and neuron loss. The greater loss of neurons in young rats supports the hypothesis that a high density of GABAA receptors protects neurons from excessive excitatory input during a sensitive period in development.
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Alexander Johnson's Ni' Concerto (1994) - Concerto no. 1 for Piano and Orchestra: a Discussion of Influences from Africa, Eastern and Western Europe
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Date: August 2001
Creator: Malan, Petronel
Description: In the new generation of artists emerging in South Africa, Alexander Johnson is considered the most prolific young composer of his day. In a recent review in the Pretoria News, Johnson has been praised by eminent critic Paul Boekkooi as a composer who has “an ear for the exotic and knows exactly how to bring it off....” He continued by noting that his music is “mentally engrossing, pleasurable to the senses and seems refreshingly free from dogmatic formulas." Johnson writes for musicians and the general public to equal satisfaction. His accessible compositions and catching use of melodic materials have made his writings very popular both in South Africa and abroad. During his residency in Belgrade in 1993-94, Johnson met Croatian pianist Dorian Leljak. Impressed with Johnson's compositional ideas and output, Leljak commissioned a work from Johnson for piano and orchestra. The result was the Ni Concerto, which Johnson completed in April 1994. The world premiere took place on June 23, 1994 with the Ni Philharmonic Orchestra conducted by Anatoli Nowiestski with Dorian Leljak as soloist. The Ni Concerto received its South African premiere in 1995 during a simultaneous celebration for “Europe Day” and the new democracy of the Republic of ...
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Alternative Information Processing Formats for Overcoming Information Processing Deficits in Senior Adults
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Date: December 2000
Creator: Muller, Lynn F.
Description: The objective of this study was to examine the effectiveness of alternative advertising presentation formats, and the quantity of information presented in advertisements in overcoming possible information-processing deficits in senior adults that could affect their recall of ad attributes and brand name, the cognitive responses generated, and attitude toward the ad. In addition, the study examined the effectiveness of retirement status as a classification or segmentation variable in comparison with the use of the more traditional classification variable, chronological age. A convenience sample of senior adult volunteers from church groups, social clubs, and civic organizations from the local area were randomly assigned to one of nine experimental conditions. The experiment utilized a simulated magazine to test the effects of presentation formats (3 levels), and quantity of information (3 levels) on senior adult's recall, cognitive responses and attitude toward the test ads. Covariates (gender, wealth, education, activity level, health, and income) were used to reduce variance. The findings clearly indicate that the presentation format of the can ad adversely affected the memory of some senior adults. In addition, the results were significantly different across the different age levels. Retirement status was less beneficial than chronological age in the current study, but ...
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The American doctrine for the use of naval gunfire in support of amphibious landings: Myth vs. reality in the Central Pacific of World War II.
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Date: December 2006
Creator: Mitchener, Donald Keith
Description: The United States Marine Corps and the United States Navy developed during the interwar period a doctrine that addressed the problems inherent in the substitution of naval gunfire for artillery support in an amphibious assault. The invasion of Betio Islet, Tarawa Atoll, in November of 1943 was the first test of this doctrine. It has been said many times since the war that the doctrine basically passed this test and that lessons learned at Tarawa increased the efficiency with which the Marine Corps and Navy applied the prewar doctrine during the rest of the war. An analysis of the planning and execution of naval bombardments in the Central Pacific Campaign, after the invasion of the Gilberts, does not support this claim. This analysis leads the researcher to three conclusions. First, the Japanese developed defenses against many of the effects of the gunfire support doctrine that blunted much of the force of American firepower. American planners were slow to recognize the implications of these changes and, consequently, were slow to react to them. Second, many naval commanders responsible for providing naval gunfire support for Central Pacific operations still equated tonnage of ordnance to effectiveness of bombardment, regardless of their frequent references ...
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Analysis of a cotton gene cluster for the antifungal protein osmotin.
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Date: December 2003
Creator: Wilkinson, Jeffery Roland
Description: Three overlapping genomic clones covering 29.0 kilobases of cotton DNA were found to encompass a cluster of two presumptive osmotin genes (OSMI and OSMII) and two osmotin pseudogenes (OSMIII and OSMIV). A segment of 16,007 basepairs of genomic DNA was sequenced from the overlapping genomic clones (GenBank Accessions AY303690 and AF304007). The two cotton osmotin genes were found to have open reading frames of 729 basepairs without any introns, and would encode presumptive osmotin preproteins of 242 amino acids. The open reading frames of the genes are identical in sequence to two corresponding cDNA clones (GenBank Accessions AF192271 and AY301283). The two cDNA inserts are almost full-length, since one lacks codons for the four N-terminal amino acids, and the other cDNA insert lacks the coding region for the 34 N-terminal amino acids. The cotton osmotin preproteins can be identified as PR5 proteins from their similarities to the deduced amino acid sequences of other plant osmotin PR5 preproteins. The preproteins would have N-terminal signal sequences of 24 amino acids, and the mature 24 kilodalton isoforms would likely be targeted for extracellular secretion. Prospective promoter elements, including two ethylene response elements, implicated as being positive regulatory elements in the expression of a ...
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