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You searched for subject:(IM1). Showing records 1 – 3 of 3 total matches.

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Texas A&M University

1. Merchant, Lance William. Neutronics Simulations of Graphite Experiments.

Degree: 2016, Texas A&M University

A widely used method for Neutronics simulations is MCNP6. Throughout this work, multiple MCNP6 simulations were completed on different supercomputers. These simulations entailed realistic representations of experiments being completed. The IM1 configuration was simulated with the corrected source definition. This geometry resulted in 0.222 as the graphite to air ratio. The IM1 experiment required many different configurations to be modeled in MCNP6. In order to further characterize the experiment different boric acid concentrations were poured in a beaker. The boric acid concentration produced an exponential fit, this represented the decrease in absorptions per second as the boric acid concentration was increased. With the progression of the project a more complex problem was created. This year 5 geometry was approached primarily through a straightforward stacked air duct problem. These results concluded that with the addition of a more complex geometry MCNP6 would require many neutron particle histories and become computationally expensive. Finally, in anticipation of the arrival of the neutron generator safety calculations were completed. These calculations yielded an estimated dose of 107.04 ? 0.3 mrem per hour in the entrance way during operation. The estimated dose was less than 5 mrem per hour in every other location of concern. The geometries were developed in MCNP6 and converted into PDT readable formats. This work was completed in order to aid in the validation of PDT development. Advisors/Committee Members: Adams, Marvin L (advisor), McClarren, Ryan G (advisor), Rauchwerger, Lawrence (committee member).

Subjects/Keywords: Graphite; CERT; AmBe; Americium; Beryllium; Americium-Beryllium; Boric Acid; IM1; Year 5; Impurities Model

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Merchant, L. W. (2016). Neutronics Simulations of Graphite Experiments. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/159090

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Merchant, Lance William. “Neutronics Simulations of Graphite Experiments.” 2016. Thesis, Texas A&M University. Accessed March 20, 2019. http://hdl.handle.net/1969.1/159090.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Merchant, Lance William. “Neutronics Simulations of Graphite Experiments.” 2016. Web. 20 Mar 2019.

Vancouver:

Merchant LW. Neutronics Simulations of Graphite Experiments. [Internet] [Thesis]. Texas A&M University; 2016. [cited 2019 Mar 20]. Available from: http://hdl.handle.net/1969.1/159090.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Merchant LW. Neutronics Simulations of Graphite Experiments. [Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/159090

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Couve-Deacon, Elodie. Epidémiologie et régulation des intégrons de classe 1 chez Acinetobacter Baumannii : Epidemiology and regulation of class 1 integrons in Acinetobacter baumannii.

Degree: Docteur es, Immunologie, oncologie et infectiologie, 2017, Limoges

Acinetobacter baumannii est un pathogène opportuniste qui prend une importance clinique croissante du fait de l’acquisition de multi-résistance. Nous avons étudié chez A. baumannii les caractéristiques et la régulation des intégrons de classe 1 (IM1) qui sont des systèmes génétiques favorisant l’acquisition, l’expression et la dissémination des gènes de résistance aux antibiotiques. Nous avons montré qu’il existe une prédominance des promoteurs des cassettes Pc fort in vivo dans une collection d’isolats cliniques et d’environnement hospitalier et in silico dans les IM1 chez A. baumannii. Nous avons aussi montré que l’expression des Pc chez A. baumannii est 4 fois plus faible que chez E. coli, quel que soit le variant de Pc. Deux explications sont possibles pour la sélection des Pc forts chez A. baumannii : (i) la nécessité d’avoir un niveau d’expression suffisant en clinique pour survivre à la pression de sélection antibiotique et (ii) la nécessité d’une régulation de l’expression de l’intégrase, représentant un coût biologique important. En effet, A. baumannii ne possède pas le système de répression par LexA existant chez E. coli. Nos résultats ouvrent le champ de l’étude de la régulation des IM1 chez A. baumannii et ainsi l’identification de nouvelles voies d’action pour lutter contre l’antibio-résistance

Acinetobacter baumannii is an opportunistic pathogen of increasing clinical importance due to the acquisition of multi-resistance. We studied in A. baumannii the characteristics and regulation of class 1 integrons (IM1), which are genetic systems that favor the acquisition, expression and dissemination of antibiotic resistance genes. We have shown that there is a predominance of strong Pc cassette promoters, in vivo, in a collection of clinical and hospital environment isolates, and in silico, from A. baumannii IM1 published in NCBI. We have also shown that the expression of Pc in A. baumannii is 4-fold lower than in E. coli, regardless of the Pc variant. Explanations that can be raised for the selection of strong Pc in A. baumannii are: (i) the need for a sufficient level of antibiotic resistance expression to survive the selection pressure in clinical environment; and (ii) the need for regulation of the integrase expression, which is of significant biological cost. Indeed A. baumannii does not have the LexA repression system existing in E. coli. Our results open the field of the study of IM1 regulation in A. baumannii and thus the identification of new pathways to fight antibiotic resistance.

Advisors/Committee Members: Ploy, Marie-Cécile (thesis director), Garnier, Fabien (thesis director).

Subjects/Keywords: Acinetobacter baumannii; Régulation; Épidémiologie; Antibiorésistance; PcS; Promoteur de l’intégrase; Promoteur des cassettes; IM1; Intégron; E. coli; Acinetobacter baumannii; Regulation; Epidemiology; Antibiotic resistance; PcS; Integrase promoter; Cassette promoter; IM1; Integron; E. coli; 610

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Couve-Deacon, E. (2017). Epidémiologie et régulation des intégrons de classe 1 chez Acinetobacter Baumannii : Epidemiology and regulation of class 1 integrons in Acinetobacter baumannii. (Doctoral Dissertation). Limoges. Retrieved from http://www.theses.fr/2017LIMO0116

Chicago Manual of Style (16th Edition):

Couve-Deacon, Elodie. “Epidémiologie et régulation des intégrons de classe 1 chez Acinetobacter Baumannii : Epidemiology and regulation of class 1 integrons in Acinetobacter baumannii.” 2017. Doctoral Dissertation, Limoges. Accessed March 20, 2019. http://www.theses.fr/2017LIMO0116.

MLA Handbook (7th Edition):

Couve-Deacon, Elodie. “Epidémiologie et régulation des intégrons de classe 1 chez Acinetobacter Baumannii : Epidemiology and regulation of class 1 integrons in Acinetobacter baumannii.” 2017. Web. 20 Mar 2019.

Vancouver:

Couve-Deacon E. Epidémiologie et régulation des intégrons de classe 1 chez Acinetobacter Baumannii : Epidemiology and regulation of class 1 integrons in Acinetobacter baumannii. [Internet] [Doctoral dissertation]. Limoges; 2017. [cited 2019 Mar 20]. Available from: http://www.theses.fr/2017LIMO0116.

Council of Science Editors:

Couve-Deacon E. Epidémiologie et régulation des intégrons de classe 1 chez Acinetobacter Baumannii : Epidemiology and regulation of class 1 integrons in Acinetobacter baumannii. [Doctoral Dissertation]. Limoges; 2017. Available from: http://www.theses.fr/2017LIMO0116


University of Victoria

3. Hanson, Mark. Immune evolution in the Immigrans-Tripunctata clade of Drosophila.

Degree: Department of Biology, 2015, University of Victoria

Drosophila melanogaster has been integral to unravelling the mechanisms of animalian immunity. Diverse species of Drosophila with sequenced genomes have been used to characterize how immune systems respond to natural selection. However, Drosophila is an incredibly speciose lineage, especially so in the subgenus Drosophila. Of the 12 genomes sequenced in 2007, ushering in the era of Drosophila comparative genomics, only three were subgenus Drosophila flies, and none were from the lesser- characterized Immigrans-Tripunctata clade. Recently, multiple Immigrans-Tripunctata clade Drosophila have been sequenced, including the transcriptome of Drosophila neotestacea. I investigated the realized immune responses of D. neotestacea to characterize the immune repertoire of this divergent lineage. The signalling pathways of D. neotestacea were largely conserved, though there were interesting patterns of evolution in antimicrobial peptide genes (AMPs). One of these AMPs, a diptericin, was highly dissimilar to diptericins in D. melanogaster, and conserved in other subgenus Drosophila flies. This prompted me to characterize the evolution of the diptericin gene family in Drosophila. I found that Drosophila diptericins have evolved under positive selection, and display intriguing differences in net charge to well-conserved diptericin domains. I assessed the expression profile of this divergent D. neotestacea diptericin, and found that it did not respond to Serratia bacterial challenge, unlike diptericin in D. melanogaster. I also highlight a potential novel drosocin-like AMP conserved throughout the subgenus Drosophila. These results agree that signalling pathways are highly conserved in diverse insects, including Drosophila. However seemingly-conserved effectors of the Drosophila immune response (such as AMPs) may have previously unappreciated variation in expression and function. Advisors/Committee Members: Perlman, Steven John (supervisor).

Subjects/Keywords: Drosophila; neotestacea; AMP; diptericin; attacin; antimicrobial peptide; melanogaster; immune; immunity; toll; imd; drosocin; metchnikowin; IM1; IM4; bomanin; albomicans; guttifera; testacea; immigrans; tripunctata

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Hanson, M. (2015). Immune evolution in the Immigrans-Tripunctata clade of Drosophila. (Masters Thesis). University of Victoria. Retrieved from http://hdl.handle.net/1828/6972

Chicago Manual of Style (16th Edition):

Hanson, Mark. “Immune evolution in the Immigrans-Tripunctata clade of Drosophila.” 2015. Masters Thesis, University of Victoria. Accessed March 20, 2019. http://hdl.handle.net/1828/6972.

MLA Handbook (7th Edition):

Hanson, Mark. “Immune evolution in the Immigrans-Tripunctata clade of Drosophila.” 2015. Web. 20 Mar 2019.

Vancouver:

Hanson M. Immune evolution in the Immigrans-Tripunctata clade of Drosophila. [Internet] [Masters thesis]. University of Victoria; 2015. [cited 2019 Mar 20]. Available from: http://hdl.handle.net/1828/6972.

Council of Science Editors:

Hanson M. Immune evolution in the Immigrans-Tripunctata clade of Drosophila. [Masters Thesis]. University of Victoria; 2015. Available from: http://hdl.handle.net/1828/6972

.