116,321 research outputs found
David O. Johnson Letter
No full textA letter sent by Private First Class David O. Johnson from Virginia Polytechnic Institute in Blacksburg, Virginia on July 13, 1943 to the First Christian Church of Morehead, Kentucky.https://scholarworks.moreheadstate.edu/mfcc_ww2_letters/1026/thumbnail.jp
Three Song Cycles by Trevor Hold: Pitt, Wilson-Johnson Dutton CDLX 7213 2008
No full textRecorded at Turner Sims Concert Hall, University of Southampton, 13-14 September & 20 December 2007The celebrated baritone David Wilson-Johnson makes his debut on Dutton Epoch, with soprano Amanda Pitt and pianist David Owen Norris in a heartfelt group of song- cycles by the Northamptonshire composer Trevor Hold. Following the success of Dutton Epoch’s recording of Hold’s song cycle The Unreturning Spring (CDLX 7196), the team present three of the composer’s engrossing song cycles: The Image Stays, River Songs and Voices from the Orchard. Norris and Wilson-Johnson, who have uniquely championed Trevor Hold’s music, include Voices from the Orchard, the composer’s tribute to his champions ‘the two Davids in memory of Henry Williamson’<br/
The Griffith University Environmental Engineering Industry Program
No full textGriffith Sciences, Griffith School of EngineeringFull Tex
David & Celestine Johnson interview #2
No full text36 p. transcript of an interview with David & Celestine Johnson conducted by Margaret Whitehead on June 7, 1979. Tape number IH-BC.85, transcript disc 184.An interview that consists of general reminiscences of their lives at the Mission Indian Residential school.Othern
David Bancroft Johnson Travel Journals - Accession 32 - M9 (32)
No full textThe David Bancroft Johnson Travel Journals Collection consists of a diary of a trip taken by David Bancroft Johnson, Founder and First President of Winthrop, to Belgium, Holland, Germany, Switzerland, France, England, and Scotland October- December 1908. The journals contain descriptions of areas visited, social life and customs, and educational practices. Also included is a description of his trip to Denver, Colorado in July 1909 in which he describes the area and its people.https://digitalcommons.winthrop.edu/manuscriptcollection_findingaids/1031/thumbnail.jp
Johnson, David W. -- 1954 -- Correspondence, Individual -- letter, 1967-05-17
No full textLetter from Johnson, Karl M. to Sabin, Albert B. dated 1967-05-17.Sabin Collection Fair Use Policy</a
Assessing Maternal, Environmental and Individual Risk Indicators for Dental Caries in a Population of Children from Queensland, Australia
No full textOral diseases affect 3.9 billion people worldwide, and dental caries is the most prevalent oral condition. Untreated caries in permanent and deciduous dentitions were reported among approximately 35% and 9% of the world population, respectively, in 2010. Moreover, it is the fourth-most expensive chronic disease to treat according to the World Health Organization. The importance of various social, environmental, familial, and behavioural factors on childhood caries has been identified by earlier researchers. In the past, epidemiological research on caries has mainly focused on describing biological and dietary determinants of the disease. During the past few decades, there has been an effort to explore children’s oral health outcomes using a broader framework, incorporating behavioural, social, and environmental predictors with biological and genetic factors. Despite the fact that these characteristics have been found to be significantly associated with childhood caries experience in different population groups, there has been scarce research exploring the whole range of putative risk factors, and their associated risk indicators, and their possible interactions, simultaneously, in a single child cohort. In particular, the impact of the epigenome and of the in utero environment on susceptibility to dental caries has not been reported in children from a typical Western industrialised country. Hence, this thesis explored a wide range of factors: environmental, socio-economic, behavioural, maternal (including throughout pregnancy), children’s individual factors (including well-established risks associated with diet and hygiene practices), and a screen for epigenetic modifications, as indicators of risk for childhood caries.
Participants were 174, six- to seven-year-old children and their mothers from South East Queensland, who were originally enrolled in the Environments for Healthy Living (EFHL) Griffith University birth cohort study. Participants for the oral health sub-study were volunteers obtained from the EFHL database who were willing to come for an oral examination at Griffith dental clinics.
Mothers completed a questionnaire on oral health knowledge and behaviours at the dental clinic followed by anthropometric measurements. Trained and calibrated examiners conducted detailed head and neck, and oral examinations, and recorded participant’s salivary characteristics and dental caries scores. Total DNA was extracted from each participant’s saliva for sequencing and methylation arrays to detect epigenetic changes. Descriptive statistics, negative binomial regression, and path analyses were performed to evaluate the associations between risk indicators and the lifetime dental caries experience of each child.
Maternal risk indicators included mother’s age at examination, her lifetime caries experience, oral health knowledge and practices, body mass index, saliva characteristics of clinical oral hydration, stimulated flow rate, pH, buffering capacity, and load of salivary mutans Streptococci and Lactobacilli.
Results indicated that low annual household income was a risk indicator for dental caries experience in this child population. Maternal behaviours: initiating child’s tooth brushing later than six months of age and a high frequency of giving carbonated drinks to the child were associated with increased caries experience in their children. In addition, high loads of maternal oral Lactobacilli were related to the children’s increased risk of caries. Moreover, children’s past caries experience, and increased levels of salivary mutans Streptococci were recognised to be significant risk indicators for their dental caries experience. Children whose mothers took iron supplements during pregnancy had low levels of caries (past and current) compared to their counterparts.
One highlight of the thesis has been the cutting-edge evidence of an association between epigenetic modifications and caries experience of individuals. There were significant differences in differentially methylated regions between persons with high and low caries experience on chromosomes 1, 2, 5, 7, 12, 20 and 22. Chromosome 12, in particular, showed the highest average methylation difference between the two groups. Further, functional annotations of related genes revealed that there are two gene clusters related to zinc (Zn) metabolism and membrane protein functions, which could indirectly be related to the caries process.
In summary, the study found maternal, environmental, and children’s characteristics that were risk indicators for caries experience in this child population. It was observed that low maternal income and poor oral health behaviours had positive associations with children’s caries experience. Also, bad oral health of the mother, expressed as maternal caries experience, placed their children at risk of dental caries. Similarly, children with poor oral health with past caries and high counts of cariogenic bacteria, along with reported low maternal iron supplements during pregnancy were more at risk of continuing to develop dental caries than their counterparts. The latter could reflect inadequate iron during pregnancy and consequent sub-optimal development of foetal tissues and immune responses. The pilot study of 12 mother child dyads to explore associations between epigenetic changes and lifetime caries experience suggests that epigenetic modifications might, indeed, predispose individuals to dental caries. However, with such a small sample size, this cannot be a firm conclusion. Nevertheless it leads to the generation of hypotheses which can be tested in further studies.”
This thesis adds new knowledge to the current literature on local, systemic and environmental factors influencing susceptibility and resistance to the process of childhood caries. The results also offer new avenues for health promotion using a common risk factor approach to improve maternal behaviours and nutrition, which would eventually enhance the clinical caries outcomes in children.Thesis (PhD Doctorate)Doctor of Philosophy (PhD)School of Dentistry&Oral HlthGriffith HealthFull Tex
The Role of Viral and Cellular Factors in Regulating HIV-1 Reverse Transcription
No full textThe human immunodeficiency virus type 1 (HIV-1) is a complex retrovirus whose genome encodes 9 genes coding for 15 different proteins. Many of these proteins are required to facilitate the hallmark process of retroviral replication, reverse transcription. Reverse transcription is a complex, multistep process, during which the virus converts single stranded RNA genome into a double stranded DNA, which can then integrate into the host cell genome. Many studies have indicated that reverse transcription is a tightly-regulated process, with multiple factors contributing to this regulation, both viral and cellular. The research herein examines how different factors affect this process. RNA factors have long been believed to play a role in regulating reverse transcription, although the precise mechanisms by which they may regulate the process has never been fully characterised. Chapter two describes for the first time an RNA element called the repressor of reverse transcription (RRT) that appears to downregulates initiation of reverse transcription immediately following viral entry into the cell. Loss of this repression results in severe replication defects in cells. Results suggest that this loss of replication is due to defective formation of the viral pre-integration complex following completion of reverse transcription, resulting in degradation of the viral cDNA following entry into the nucleus. This study potentially explains previous observations that there is a lag between viral entry into the cell and initiation of reverse transcription, as well as showing that deregulation of reverse transcription is detrimental to viral replication.
Multiple studies have shown that protein interactions with RNA elements are required for efficient reverse transcription to occur. Chapter three investigates the role of the viral Tat protein in regulating reverse transcription. Multiple studies have suggested a role for Tat in reverse transcription, but there are conflicting views on what that role may be. In this study an in vitro assay was established to mimic initiation of reverse transcription in a cell-free environment. The results showed that at low concentrations, Tat upregulates initiation of reverse transcription, but at high concentrations it switches to suppression of the same process. The alternate effects of 8 the Tat protein at high and low concentrations could explain the discrepancy observed between various studies. Further analysis showed that Tat does not interact with the RNA template to mediate the effect but instead interacts with the RT protein directly, possibly stabilising the heterodimeric form of the protein to allow more efficient initiation to occur. Upregulation required a number of Tat domains, including the basic domain, which was surprising since previous studies indicated that this domain was not required for Tat to mediate reverse transcription.
The basic domain of Tat is required to mediate several Tat functions. It contains an arginine-rich motif (ARM) that contains the RNA binding domain, as well as an extra-cellular receptor interaction domain, and the nuclear localisation signal that is required for Tat accumulation in the nucleus. Chapter three showed that the basic domain is also required for reverse transcription to occur, a finding that was expanded upon in chapter four. A transdominant mutant of Tat, Nullbasic, was made, and the effects on viral replication analysed. The results showed that expression of Nullbasic significantly suppressed viral production from cells, caused by decreased Env and Gag expression. Nullbasic was found to inhibit Rev mediated export of viral mRNA, resulting in the observed reduction in proteins expressed from unspliced or singlyspliced mRNA transcripts. Furthermore, virus produced from cells expressing Nullbasic was poorly infectious. These viruses were found to be highly defective for reverse transcription, indicating that Nullbasic is impairing efficient initiation of reverse transcription in the virion. The multiple inhibitory effects of Nullbasic on viral replication indicated that it was a possible candidate for treatment of viral infection.
To test this principle, Nullbasic was expressed in a reporter cell line and then challenged with high dose HIV-1. Interestingly, Nullbasic caused a greater than 800- fold decrease in viral replication, indicating that it may potentially be useful as a therapeutic in the future, however there are significant obstacles to be overcome before this becomes a reality.
Overall, this study addresses the role of multiple factors in regulating reverse transcription, while highlighting multiple regions that could provide potential therapeutic applications.Thesis (PhD Doctorate)Doctor of Philosophy (PhD)Griffith Medical Research CollegeGriffith HealthFull Tex
David Wark Griffith
No full textPalao, JA. (1999). David Wark Griffith. Banda aparte. (14):134-135. https://riunet.upv.es/handle/10251/42354.Importación Masiva1341351
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The David W. Fentress Family Letters, 1856-1969
No full textTranscript of a letter by an unidentified author to David Fentress regarding sharing federal newspapers and the banning of federal newspapers in some areas. The author passes on the news of the war including the destruction of the Federal merchantmen by the Confederate fleet. He passes along world news: Russia preparing to go to War with Europe and how that could negatively affect the Confederacy. There is also speculation on the future of the war
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