A Possible luxR Solo Type Regulator of an Antibiotic-Like Compound from the Soil Bacterium Rhodococcus

Rhodococcus, a species of bacteria commonly found in the soil, is an under-explored producer of small bioactive compounds including siderophores, pigments and antibiotics. MTM3W5.2 is a strain of Rhodococcus that was previously discovered to produce an antibiotic-like compound that has inhibitory effects on other Rhodococcus strains, including the veterinary pathogen, R. equi. The biosynthetic gene cluster responsible for production of the antibiotic has been identified, and a small gene, BTZ20_3964 at the start of the operon is believed to be a luxR solo regulator of the gene cluster. The goal of this project was to determine this gene’s status as a regulator for the gene cluster. Merodiploids were constructed using the deletion construct, pEX18Km3964AD to obtain a double crossover recombination event to replace the functional gene with the deletion construct. However, evidence indicates that an illegitimate recombination event occurred to produce a merodiploid strain

Alien Registration- Sellick, Ethel (South Portland, Cumberland County)

https://digitalmaine.com/alien_docs/20425/thumbnail.jp

Alien Registration- Sellick, Ethel (South Portland, Cumberland County)

https://digitalmaine.com/alien_docs/20425/thumbnail.jp

Alien Registration- Sellick, Ethel (South Portland, Cumberland County)

https://digitalmaine.com/alien_docs/20425/thumbnail.jp

Experiences of Agricultural Education Preservice Teachers Engaging in Critical Friendships

Like educators in other disciplines, agricultural education preservice teachers must find ways to improve as teachers using methods such as reflection or peer observation. Critical friendship combines both, promoting reflection through the use of a critical friend who observes an individual’s teaching and provides constructive criticism to help the individual advance their practice. This qualitative study sought to use the critical friendship concept to assist agricultural education preservice teachers in reflecting on their teaching techniques. Participants were randomly assigned to one of two groups; one group selected a critical friend in agricultural education, and the other group selected a critical friend in an educational discipline outside of agricultural education. Participants were asked to have a conversation with their critical friend each week, and reflect on the conversation in their journals. Audio from conversations from week four through week six of the study were recorded. The participants were also required to arrange for their critical friend to come observe them teaching a lesson plan prepared by the researchers and then reflect on the experience together. At the end of the student teaching internship, participants were asked to engage in one-on-one interviews with the researcher about their experiences in a critical friendship. The audio recorded conversations and interviews were transcribed and coded for themes. Different themes emerged from the conversations between two agricultural education preservice teachers and between an agricultural education preservice teacher and a teacher in a different educational discipline. The two agricultural education preservice teachers discussed teaching concerns and sought feedback from each other about potential solutions. The agricultural education preservice teacher and the non-agricultural education critical friend used the conversations to establish common ground as teachers. The same themes emerged from the interviews regardless of the type of critical friend. Participants found critical friendships to be beneficial, but cautioned that there were certain characteristics that allowed their critical friendships to develop

Discovery, analysis, and utility of bovine single nuclotide polymorphisms

Thesis (Ph.D.) -- University of Adelaide, Dept. of Animal Science, 2002

Visual Methods of Monitoring the Effect of Wettability on Fines Migration in Sandstones

Global energy demands are changing, with focus on replacement of hydrocarbons with renewables. However, the reliance on hydrocarbons cannot be removed in the short term, so any methods to improve the efficiency and environmental profile of hydrocarbon extraction are needed. Hydrocarbon extraction rate may be reduced if the formation becomes damaged during the extraction process. This damage may be particularly problematic during low salinity enhanced oil recovery (EOR) and although there are many mechanisms by which this may happen, the mechanism which is of particular interest in this work is that of fines migration, especially in combination with variation of wettability. This work considers a variety of different methods to investigate the ways in which fine mineral particles move when encountering surfaces with variable wettability, and new test methods to rapidly assess the fines migration potential of a sandstone. Throughout this work, 3D printing is used to assist in these investigations, and hence firstly a comprehensive study of the wettability of commonly used 3D printing materials was undertaken which showed good agreement with the literature. Contributions to the wettability of aspects of the printing process resulting in variation of roughness was also evaluated but did not correlate at the length scales studied. Secondly, a study of the likelihood of removal of fines from sandstones by ultrasonic treatment in various salinity brines was performed, finding increased removal in low salinity brines and giving general agreement to those previously reported in the literature. Finally, several conceptual experiments looking at methods to monitor the movement of fine particles over surfaces of variable wettability, including drop spread and flow through 3D printed flow cells with individual particle tracking, were carried out. The results were compared to flow simulations and showed good agreement between particle tracking and simulated flow