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University of Georgia
1.
Martin, Jacob Leeds.
A construct validation for a resistance by Perceived Injustice Scale.
Degree: PhD, Psychology, 2015, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201505_phd 
► This study develops and validates the Resistance by Perceived Injustice Scale (RPIS), which aims to capture attitudes of race and fairness in a way that…
(more)
▼ This study develops and validates the
Resistance by Perceived Injustice Scale (RPIS), which aims to capture attitudes of race and fairness in a way that explains
resistance to organizational diversity policies and strategy. Through initial item generation and three studies, this scale is shown to be a reliable and valid measure which exhibits sufficient psychometric properties. Specifically, the RPIS is reduced to a final set of 17 items, captures distinct but interrelated dimensions, and is shown to be unique from existing related concepts. Finally, this scale is shown to predict support attitudes for many organizational diversity policies and strategies, and in some cases, explains variance in these attitudes beyond modern racism attitudes. This study not only adds to the diversity measurement literature by creating a scale more predictive of
resistance than existing modern racism scales, but also helps explain how such modern prejudice manifests to express
resistance.
Advisors/Committee Members: Karl Kuhnert.
Subjects/Keywords: Resistance
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APA (6th Edition):
Martin, J. L. (2015). A construct validation for a resistance by Perceived Injustice Scale. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201505_phd
Chicago Manual of Style (16th Edition):
Martin, Jacob Leeds. “A construct validation for a resistance by Perceived Injustice Scale.” 2015. Doctoral Dissertation, University of Georgia. Accessed February 27, 2020.
http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201505_phd.
MLA Handbook (7th Edition):
Martin, Jacob Leeds. “A construct validation for a resistance by Perceived Injustice Scale.” 2015. Web. 27 Feb 2020.
Vancouver:
Martin JL. A construct validation for a resistance by Perceived Injustice Scale. [Internet] [Doctoral dissertation]. University of Georgia; 2015. [cited 2020 Feb 27].
Available from: http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201505_phd.
Council of Science Editors:
Martin JL. A construct validation for a resistance by Perceived Injustice Scale. [Doctoral Dissertation]. University of Georgia; 2015. Available from: http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201505_phd
University of Utah
2.
Tidwell, Timothy James.
Insulin signaling in the hearts of uncoupling protein three knockout mice on a high fat diet.
Degree: Honors BS;, Biology;, 2009, University of Utah
URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1658/rec/651
► INTRODUCTION: People with diabetes are at high risk for cardiovascular disease; which is the major cause of death in diabetics. Current research suggests that excessive…
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▼ INTRODUCTION: People with diabetes are at high risk for cardiovascular disease; which is the major cause of death in diabetics. Current research suggests that excessive mitochondrial uncoupling is a potential mechanism for cardiac dysfunction in diabetic patients. Uncoupling protein 3 (UCP3) is an inner mitochondrial membrane protein that reduces the amount of reactive oxygen species (ROS) produced in the mitochondrial matrix by uncoupling the mitochondria. Mice lacking UCP3 (UCP3KO) have been shown to accumulate ROS and diacylglycerol in cardiac muscle. These two molecules have been shown to induce insulin resistance in skeletal muscle. The goal of my project was to determine if the absence of UCP3 in the heart will exacerbate diet-induced insulin resistance in the murine heart. MATERIALS AND METHODS: Whole heart homogenates were extracted from four groups of mice: (1) wild type (WT) fed normal chow (NC); (2) WT fed a high fat diet for 10 weeks (HF); (3) UCP3KO NC and (4) UCP3KO HF. Insulin signaling was examined using western-blotting to assess the phosphorylation status of key components of the insulin signaling pathway under non insulin and insulin-stimulated conditions in each group. Values form each group were analyzed using an ANOVA followed by a t test to determine any statistical significant differences between the groups. RESULTS: Phosphorylation of protein kinase B (Akt) (at serine 473 or threonine 308) and the downstream target glycogen synthase kinase 3 p at serine 9 was the same between all the groups. CONCLUSIONS: two major conclusions arise from this work; ( 1 ) 1 0 weeks of high fat diet does not affect insulin signaling in the heart and (2) despite increased ROS and DAG levels in the hearts of UCP3KO mice, insulin sensitivity was maintained. We speculate that UCP3KO mice have developed compensatory mechanisms that prevented the development of insulin resistance despite accumulation of compounds known to induce insulin resistance. These mechanisms remain to be determined in future studies.
Subjects/Keywords: Insulin resistance
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APA (6th Edition):
Tidwell, T. J. (2009). Insulin signaling in the hearts of uncoupling protein three knockout mice on a high fat diet. (Masters Thesis). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1658/rec/651
Chicago Manual of Style (16th Edition):
Tidwell, Timothy James. “Insulin signaling in the hearts of uncoupling protein three knockout mice on a high fat diet.” 2009. Masters Thesis, University of Utah. Accessed February 27, 2020.
http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1658/rec/651.
MLA Handbook (7th Edition):
Tidwell, Timothy James. “Insulin signaling in the hearts of uncoupling protein three knockout mice on a high fat diet.” 2009. Web. 27 Feb 2020.
Vancouver:
Tidwell TJ. Insulin signaling in the hearts of uncoupling protein three knockout mice on a high fat diet. [Internet] [Masters thesis]. University of Utah; 2009. [cited 2020 Feb 27].
Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1658/rec/651.
Council of Science Editors:
Tidwell TJ. Insulin signaling in the hearts of uncoupling protein three knockout mice on a high fat diet. [Masters Thesis]. University of Utah; 2009. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1658/rec/651
University of Georgia
3.
Howell, Janet Sue.
Evaluation of three in vitro bioassays for measuring the anthelmintic activity of plant extracts containing condensed tannins.
Degree: MS, Infectious Diseases, 2009, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/howell_janet_s_200905_ms
► Certain forages high in condensed tannins (CT) demonstrate anthelmintic activity, and appear to be a useful non-chemical adjunct to parasite control in small ruminants. In…
(more)
▼ Certain forages high in condensed tannins (CT) demonstrate anthelmintic activity, and appear to be a useful non-chemical adjunct to parasite control in small ruminants. In vitro bioassays have been used to evaluate this antiparasitic effect against several species of trichostrongyle nematodes. However, it remains unclear which in vitro bioassay is the most appropriate evaluation tool. The goal of this research is to evaluate different in vitro methods, and determine which are the most suitable for measuring the effective concentration (EC50) of these extracts. In this research, 3 in vitro methods (egg hatch assay (EHA), larval development assay (LDA) and larval migration inhibition assay (LMIA) were performed using CT extracts from 4 plants with Haemonchus contortus eggs or larvae. Of the 3 bioassays, the LDA yielded the most consistent results, and therefore, appears to be the most appropriate bioassay for measuring the antiparasitic activity of CT plant extracts in small ruminants.
Advisors/Committee Members: RAY M. KAPLAN.
Subjects/Keywords: anthelmintic resistance
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APA (6th Edition):
Howell, J. S. (2009). Evaluation of three in vitro bioassays for measuring the anthelmintic activity of plant extracts containing condensed tannins. (Masters Thesis). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/howell_janet_s_200905_ms
Chicago Manual of Style (16th Edition):
Howell, Janet Sue. “Evaluation of three in vitro bioassays for measuring the anthelmintic activity of plant extracts containing condensed tannins.” 2009. Masters Thesis, University of Georgia. Accessed February 27, 2020.
http://purl.galileo.usg.edu/uga_etd/howell_janet_s_200905_ms.
MLA Handbook (7th Edition):
Howell, Janet Sue. “Evaluation of three in vitro bioassays for measuring the anthelmintic activity of plant extracts containing condensed tannins.” 2009. Web. 27 Feb 2020.
Vancouver:
Howell JS. Evaluation of three in vitro bioassays for measuring the anthelmintic activity of plant extracts containing condensed tannins. [Internet] [Masters thesis]. University of Georgia; 2009. [cited 2020 Feb 27].
Available from: http://purl.galileo.usg.edu/uga_etd/howell_janet_s_200905_ms.
Council of Science Editors:
Howell JS. Evaluation of three in vitro bioassays for measuring the anthelmintic activity of plant extracts containing condensed tannins. [Masters Thesis]. University of Georgia; 2009. Available from: http://purl.galileo.usg.edu/uga_etd/howell_janet_s_200905_ms
University of Georgia
4.
Evans, Christopher Charles.
An in vitro bioassay for measuring anthelmintic susceptibility in Dirofilaria immitis.
Degree: MS, Veterinary and Biomedical Sciences, 2011, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/evans_christopher_c_201108_ms
► The canine heartworm (Dirofilaria immitis) is a widespread parasitic filarial nematode of veterinary importance. Anthelmintics of the macrocyclic lactone (ML) drug class have been widely…
(more)
▼ The canine heartworm (Dirofilaria immitis) is a widespread parasitic filarial nematode of veterinary importance. Anthelmintics of the macrocyclic lactone (ML) drug class have been widely and effectively used in chemoprophylaxis, but an increased number of lack of efficacy reports, in which dogs develop mature infection despite consistent preventive dosing, has raised concerns that heartworms are developing
resistance. The objective of this study was to optimize an in vitro bioassay for measuring the susceptibility of heartworm populations to ML drugs and, using this assay, to compare the dose-responses of susceptible and suspected-resistant isolates. We developed and used a larval migration inhibition assay (LMIA) in which the ability of third-stage larvae to migrate through a 25-µm sieve following incubation in drug was measured. Fitting the dose-response data from the LMIA to a nonlinear regression model, we observed reproducible results, but found no differences in the IC50 values of susceptible and suspected-resistant isolates.
Advisors/Committee Members: Ray Kaplan.
Subjects/Keywords: anthelmintic resistance
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APA (6th Edition):
Evans, C. C. (2011). An in vitro bioassay for measuring anthelmintic susceptibility in Dirofilaria immitis. (Masters Thesis). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/evans_christopher_c_201108_ms
Chicago Manual of Style (16th Edition):
Evans, Christopher Charles. “An in vitro bioassay for measuring anthelmintic susceptibility in Dirofilaria immitis.” 2011. Masters Thesis, University of Georgia. Accessed February 27, 2020.
http://purl.galileo.usg.edu/uga_etd/evans_christopher_c_201108_ms.
MLA Handbook (7th Edition):
Evans, Christopher Charles. “An in vitro bioassay for measuring anthelmintic susceptibility in Dirofilaria immitis.” 2011. Web. 27 Feb 2020.
Vancouver:
Evans CC. An in vitro bioassay for measuring anthelmintic susceptibility in Dirofilaria immitis. [Internet] [Masters thesis]. University of Georgia; 2011. [cited 2020 Feb 27].
Available from: http://purl.galileo.usg.edu/uga_etd/evans_christopher_c_201108_ms.
Council of Science Editors:
Evans CC. An in vitro bioassay for measuring anthelmintic susceptibility in Dirofilaria immitis. [Masters Thesis]. University of Georgia; 2011. Available from: http://purl.galileo.usg.edu/uga_etd/evans_christopher_c_201108_ms
University of Georgia
5.
Thomas, Anna.
Sensitivity of Didymella bryoniae to DMI and SDHI fungicides and the relationship between fungicide sensitivity and control of gummy stem blight in watermelon.
Degree: MS, Plant Pathology, 2011, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/thomas_anna_201108_ms
► Baseline isolates of Didymella bryoniae were tested for sensitivity to penthiopyrad, tebuconazole and difenoconazole using mycelia growth assay. Based on the sensitivity distribution, a discriminatory…
(more)
▼ Baseline isolates of Didymella bryoniae were tested for sensitivity to penthiopyrad, tebuconazole and difenoconazole using mycelia growth assay. Based on the sensitivity distribution, a discriminatory concentration of 3.0 µg/ml was selected for future monitoring of shifts in sensitivity. Cross-
resistance between boscalid and penthiopyrad was identified in field isolates of D. bryoniae and a potential for cross-
resistance between DMIs is observed based on baseline sensitivity profile. Field experiments were conducted to establish a relationship between frequency of
resistance and fungicide efficacy in managing gummy stem blight (GSB). Tebuconazole and chlorothalonil were proved to be most effective in managing GSB. A consistent negative association was observed between the frequency of
resistance and disease control in the field. Isolation of D. bryoniae resistant to thiophanate-methyl from commercial seedlots helped explain the unpredictable development of fungicide
resistance in watermelon fields. Results from this study will help manage GSB with efficient use of fungicides.
Advisors/Committee Members: David B. Langston, Jr..
Subjects/Keywords: Cross-resistance
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APA (6th Edition):
Thomas, A. (2011). Sensitivity of Didymella bryoniae to DMI and SDHI fungicides and the relationship between fungicide sensitivity and control of gummy stem blight in watermelon. (Masters Thesis). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/thomas_anna_201108_ms
Chicago Manual of Style (16th Edition):
Thomas, Anna. “Sensitivity of Didymella bryoniae to DMI and SDHI fungicides and the relationship between fungicide sensitivity and control of gummy stem blight in watermelon.” 2011. Masters Thesis, University of Georgia. Accessed February 27, 2020.
http://purl.galileo.usg.edu/uga_etd/thomas_anna_201108_ms.
MLA Handbook (7th Edition):
Thomas, Anna. “Sensitivity of Didymella bryoniae to DMI and SDHI fungicides and the relationship between fungicide sensitivity and control of gummy stem blight in watermelon.” 2011. Web. 27 Feb 2020.
Vancouver:
Thomas A. Sensitivity of Didymella bryoniae to DMI and SDHI fungicides and the relationship between fungicide sensitivity and control of gummy stem blight in watermelon. [Internet] [Masters thesis]. University of Georgia; 2011. [cited 2020 Feb 27].
Available from: http://purl.galileo.usg.edu/uga_etd/thomas_anna_201108_ms.
Council of Science Editors:
Thomas A. Sensitivity of Didymella bryoniae to DMI and SDHI fungicides and the relationship between fungicide sensitivity and control of gummy stem blight in watermelon. [Masters Thesis]. University of Georgia; 2011. Available from: http://purl.galileo.usg.edu/uga_etd/thomas_anna_201108_ms
University of Georgia
6.
Stephens, Natalie Ann.
Protein trafficking in African trypanosomes: the role of localization of the serum resistance associated protein in the inhibition of trypanosome lytic factor-1.
Degree: PhD, Biochemistry and Molecular Biology, 2011, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/stephens_natalie_a_201112_phd
► Trypanosoma brucei or African trypanosomes are unicellular parasites that cause the veterinary wasting disease Nagana, and the human disease, Human African Trypanosomiasis. The veterinary pathogen,…
(more)
▼ Trypanosoma brucei or African trypanosomes are unicellular parasites that cause the veterinary wasting disease Nagana, and the human disease, Human African Trypanosomiasis. The veterinary pathogen, T. b. brucei, is unable to infect humans due to a trypanolytic subclass of high-density lipoprotein found in human serum called Trypanosome Lytic Factor (TLF-1). Conversely, the human infectious subspecies of African trypanosomes have evolved mechanisms of
resistance that allow them to circumvent the innate immunity of their hosts. One example of these human infectious subspecies is T. b. rhodesiense, which circumvents TLF-1 killing and survives in the mammalian bloodstream through the expression of the Serum
Resistance Associated protein (SRA).
In this study, I have defined the morphologies of TLF-1 mediated cell lysis and demonstrated that each of the lytic components of TLF-1 gives rise to a specific cell death morphology, that is likely to be due to different mechanisms of trypanosome killing. I have also identified the post-translational modifications of SRA and defined its trafficking pathway from synthesis to degradation. SRA is GPI-anchored and has an unusual localization as a resident endosomal protein, before it is ultimately targeted to the lysosomal compartment and rapidly degraded. In addition, I have identified the initial point of colocalization of SRA and TLF-1 as the early endosomal compartment and demonstrated that TLF-1 appears to be less stable in the presence of SRA.
Previous work by our group proposed that TLF-1 interacts with the negatively charged lysosomal membrane in order to mediate lysis. This interaction occurs through membrane insertion of the TLF-1 protein, apolipoprotein L-I, which also binds SRA. The mechanism of
resistance is proposed to involve the interaction of SRA and TLF-1 through the binding of ApoL-I, which blocks TLF-1 association with the lysosomal membrane. Failure of TLF-1 to associate with the membrane leaves the toxin exposed to proteolysis in the lysosomal lumen and subsequent accelerated degradation. Thus, the mechanism of T. b. rhodesiense
resistance to TLF-1 killing is likely to be a two-step process that blocks the localization of the trypanosome toxin from its required site of action, followed by clearance through lysosomal degradation.
Advisors/Committee Members: Stephen Hajduk.
Subjects/Keywords: Serum resistance
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APA (6th Edition):
Stephens, N. A. (2011). Protein trafficking in African trypanosomes: the role of localization of the serum resistance associated protein in the inhibition of trypanosome lytic factor-1. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/stephens_natalie_a_201112_phd
Chicago Manual of Style (16th Edition):
Stephens, Natalie Ann. “Protein trafficking in African trypanosomes: the role of localization of the serum resistance associated protein in the inhibition of trypanosome lytic factor-1.” 2011. Doctoral Dissertation, University of Georgia. Accessed February 27, 2020.
http://purl.galileo.usg.edu/uga_etd/stephens_natalie_a_201112_phd.
MLA Handbook (7th Edition):
Stephens, Natalie Ann. “Protein trafficking in African trypanosomes: the role of localization of the serum resistance associated protein in the inhibition of trypanosome lytic factor-1.” 2011. Web. 27 Feb 2020.
Vancouver:
Stephens NA. Protein trafficking in African trypanosomes: the role of localization of the serum resistance associated protein in the inhibition of trypanosome lytic factor-1. [Internet] [Doctoral dissertation]. University of Georgia; 2011. [cited 2020 Feb 27].
Available from: http://purl.galileo.usg.edu/uga_etd/stephens_natalie_a_201112_phd.
Council of Science Editors:
Stephens NA. Protein trafficking in African trypanosomes: the role of localization of the serum resistance associated protein in the inhibition of trypanosome lytic factor-1. [Doctoral Dissertation]. University of Georgia; 2011. Available from: http://purl.galileo.usg.edu/uga_etd/stephens_natalie_a_201112_phd
University of Georgia
7.
Bray, Adam Lee.
Characterizing soybean resistance to the kudzu bug.
Degree: MS, Plant Breeding, Genetics and Genomics, 2015, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/bray_adam_l_201505_ms
► The kudzu bug (KZB), Megacopta sp., is a newly invasive pest of soybean in the U.S.A. originating from Asia. Several screening techniques were used to…
(more)
▼ The kudzu bug (KZB), Megacopta sp., is a newly invasive pest of soybean in the U.S.A. originating from Asia. Several screening techniques were used to identify soybean host plant
resistance (HPR) to KZB. ‘Benning’ near-isogenic lines with different combinations of
resistance quantitative trait loci (QTLs) to defoliating insects from PI 229358 and PI 227687 were screened for KZB
resistance using a field cage. KZBs did not show preference to soybean lines with QTLs M, G, H and E for
resistance to leaf-chewing insects. Additionally, 30 plant introductions (PIs) with
resistance to soybean aphid or silverleaf whitefly were screened in the field. Wash-bucket sampling accurately quantified the number of KZBs on plants, and rating stem lesions provided a measure of season long insect damage. Two lines, PI 567336A and PI 567598B, were identified as resistant to KZB in the field and confirmed to have antibiosis
resistance with a no-choice assay.
Advisors/Committee Members: Wayne Parrott.
Subjects/Keywords: Insect resistance
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APA (6th Edition):
Bray, A. L. (2015). Characterizing soybean resistance to the kudzu bug. (Masters Thesis). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/bray_adam_l_201505_ms
Chicago Manual of Style (16th Edition):
Bray, Adam Lee. “Characterizing soybean resistance to the kudzu bug.” 2015. Masters Thesis, University of Georgia. Accessed February 27, 2020.
http://purl.galileo.usg.edu/uga_etd/bray_adam_l_201505_ms.
MLA Handbook (7th Edition):
Bray, Adam Lee. “Characterizing soybean resistance to the kudzu bug.” 2015. Web. 27 Feb 2020.
Vancouver:
Bray AL. Characterizing soybean resistance to the kudzu bug. [Internet] [Masters thesis]. University of Georgia; 2015. [cited 2020 Feb 27].
Available from: http://purl.galileo.usg.edu/uga_etd/bray_adam_l_201505_ms.
Council of Science Editors:
Bray AL. Characterizing soybean resistance to the kudzu bug. [Masters Thesis]. University of Georgia; 2015. Available from: http://purl.galileo.usg.edu/uga_etd/bray_adam_l_201505_ms
University of Georgia
8.
Wright, Meredith Suzanne.
Evolutionary processes in aquatic bacteria: the transfer and transport of antibiotic resistance in industrially contaminated systems.
Degree: PhD, Ecology, 2007, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/wright_meredith_s_200708_phd
► The presence of antibiotic resistant bacteria in non-clinical environments is the result of multiple selective pressures and evolutionary processes. To test the hypothesis that metal…
(more)
▼ The presence of antibiotic resistant bacteria in non-clinical environments is the result of multiple selective pressures and evolutionary processes. To test the hypothesis that metal exposure is one selective pressure maintaining antibiotic
resistance in aquatic bacteria, both bacterial community tolerance to metals and antibiotics and the relative abundance of antibiotic and metal
resistance determinants were quantified along a gradient of metal contamination in freshwater microbial microhabitats on the Savannah River Site (SRS), SC, and in experimental freshwater microcosms. Phenotypic
resistance to metals and antibiotics, and
resistance determinants were greatest in metal-exposed bacterial communities supporting the hypothesis. The relative abundance of mobile genetic elements called class 1 integrons were then compared in contaminated and reference freshwater and estuarine microhabitats, and in experimental microcosms, to test the hypothesis that elements involved in the acquisition of exogenous sources of DNA are more abundant in bacterial communities exposed to metal contaminants . The structure and predicted function of the integron-associated gene cassette pool was then compared using fragment analysis to assess how metal contamination shapes the gene cassette pool. Results indicate that class 1 integrons are abundant in environmental bacteria, and gene cassettes are a diverse genetic resource that can contribute to bacterial evolution. The complete nucleotide sequence of a 130 kb plasmid from a multidrug resistant Escherichia coli strain isolated from a contaminated estuary was determined to assess potential antibiotic
resistance gene flow between clinical and environmental populations and the co-occurrence of metal and antibiotic
resistance elements on the same plasmid. The plasmid contained several genes conferring
resistance to multiple classes of antibiotics in a region with numerous insertion sequences, transposons, and integrons, yet no known metal
resistance genes were identified. The sequence reveals that antibiotic
resistance genes prevalent in clinically-derived isolates are prevalent in an environmental strain as well. The results of these studies indicate that antibiotic
resistance persists in the environment, and that metal exposure selects for
resistance phenotypes, genotypes, and genes involved in horizontal transfer.
Advisors/Committee Members: J Vaun McArthur.
Subjects/Keywords: antibiotic resistance
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APA (6th Edition):
Wright, M. S. (2007). Evolutionary processes in aquatic bacteria: the transfer and transport of antibiotic resistance in industrially contaminated systems. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/wright_meredith_s_200708_phd
Chicago Manual of Style (16th Edition):
Wright, Meredith Suzanne. “Evolutionary processes in aquatic bacteria: the transfer and transport of antibiotic resistance in industrially contaminated systems.” 2007. Doctoral Dissertation, University of Georgia. Accessed February 27, 2020.
http://purl.galileo.usg.edu/uga_etd/wright_meredith_s_200708_phd.
MLA Handbook (7th Edition):
Wright, Meredith Suzanne. “Evolutionary processes in aquatic bacteria: the transfer and transport of antibiotic resistance in industrially contaminated systems.” 2007. Web. 27 Feb 2020.
Vancouver:
Wright MS. Evolutionary processes in aquatic bacteria: the transfer and transport of antibiotic resistance in industrially contaminated systems. [Internet] [Doctoral dissertation]. University of Georgia; 2007. [cited 2020 Feb 27].
Available from: http://purl.galileo.usg.edu/uga_etd/wright_meredith_s_200708_phd.
Council of Science Editors:
Wright MS. Evolutionary processes in aquatic bacteria: the transfer and transport of antibiotic resistance in industrially contaminated systems. [Doctoral Dissertation]. University of Georgia; 2007. Available from: http://purl.galileo.usg.edu/uga_etd/wright_meredith_s_200708_phd
Texas A&M University
9.
Johnsen, Mark Miller.
The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas.
Degree: 2009, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-1298
► In 2002, West Nile virus was isolated for the first time in Harris County, Texas. The subsequent epidemic led the Harris County Mosquito Control Division…
(more)
▼ In 2002, West Nile virus was isolated for the first time in Harris County, Texas.
The subsequent epidemic led the Harris County Mosquito Control Division to initiate an
extensive spraying operation to suppress infected adult mosquitoes. The control
program was aimed at the predominate disease-carrying mosquito for the southern
United States, Culex quinquefasciatus Say. With the increase of insecticide pressure on
the mosquito populations, the possibility of
resistance was brought into question. A
three year study using a vial bioassay test was conducted in Harris (2004-2005) and
Brazos (2005-2006) counties to determine the
resistance status of Cx. quinquefasciatus
to the six chemicals (malathion, naled, resmethrin, permethrin, sumithrin, and
pyrethrum) used most frequently in adult mosquito control programs.
The
resistance ratios acquired from the vial bioassay tests were mapped onto
shapefiles for Harris and Brazos counties, which revealed clustering of areas with
pyrethroid
resistance mosquito populations in the northeastern, southeastern, and
southwestern corners of Loop 610 in Harris County. An additional six-month
preliminary study, involving six operational areas in Harris County and three in Brazos County, was conducted, demonstrating only minor fluctuations in the monthly
resistance
ratios occurring in both counties in 2005.
A significant correlation was documented between the two years of
resistance
ratios for mosquitoes to the three pyrethroids in Harris County and all the insecticides
except pyrethrum in Brazos County. A significant relationship was also found between
the resmethrin
resistance ratios and the number of spray events performed during the
previous year and the malathion
resistance ratios with the insecticide treatments
conducted in the same year. The correlation analyses provide data used to predict areas
where
resistance can develop in the mosquito population, thus providing the control
agency more data to plan future control tactics.
The overall analysis indicated that Harris County has localized pockets of
resistant mosquitoes; but, on a whole, it does not seem to have widespread
resistance in
its mosquito populations. The only
resistance that was detected was in the mosquitoes
tested against the three pyrethroids. Mosquitoes in Brazos County, which has no
organized mosquito control, demonstrated county-wide susceptibility to all six
insecticides tested.
Advisors/Committee Members: Olson, Jimmy K. (advisor), Craig, Thomas M. (committee member), Gorena, Roberto L. (committee member), Harris, Marvin K. (committee member), Russell, Leon H. (committee member).
Subjects/Keywords: Resistance; Mosquitoes
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APA (6th Edition):
Johnsen, M. M. (2009). The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1298
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):
Johnsen, Mark Miller. “The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas.” 2009. Thesis, Texas A&M University. Accessed February 27, 2020.
http://hdl.handle.net/1969.1/ETD-TAMU-1298.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Johnsen, Mark Miller. “The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas.” 2009. Web. 27 Feb 2020.
Vancouver:
Johnsen MM. The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas. [Internet] [Thesis]. Texas A&M University; 2009. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1298.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Johnsen MM. The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas. [Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1298
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
10.
Rawat, Aditi.
Prescriptions, Perceptions and Resistance - A Qualitative
Study of Public Perceptions of Antibiotic Prescriptions in Noida,
India.
Degree: School of Public Health, 2017, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:733487/
► Background/Objective: The burden of antibiotic resistance is growing and the lack of adherence to antibiotics is a major reason for its increase. Little is known…
(more)
▼ Background/Objective: The burden of antibiotic
resistance is growing and the lack of adherence to antibiotics is a
major reason for its increase. Little is known about the impact of
patients’ perceptions regarding antibiotic prescriptions and
doctor-patient communication on adherence to antibiotics. This
study assesses patients’ views of their doctors, antibiotic
prescriptions and barriers to antibiotic adherence. Design:
Qualitative, semi-structured one on one interviews. Settings:
Residential complex in Noida, Uttar Pradesh, India (2016)
Participants: Individuals of low socioeconomic status, above 20
years of age working in the residential complex. Results: Negative
interactions with doctors were found to be associated with lack of
adherence to antibiotics. Several participants indicated they
misuse antibiotics. The study found barriers, such as the cost of
medication and consultation, distance from health facility, and use
of traditional methods, to impede the effective use of antibiotics.
The study also found that none of the participants had any
knowledge about antibiotic
resistance. Conclusions: Doctor-patient
interaction is crucial to patients’ opinion about antibiotics and
impacts adherence to antibiotic therapy. More attention is needed
regarding communication between a patient and a doctor and how
patients view antibiotic therapy. Focus is also required to educate
patients about antibiotic
resistance effectively.
Advisors/Committee Members: Shield, Renée R. (Advisor), McGarvey, Stephen T. (Reader).
Subjects/Keywords: Antibiotics Resistance
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Manager
APA (6th Edition):
Rawat, A. (2017). Prescriptions, Perceptions and Resistance - A Qualitative
Study of Public Perceptions of Antibiotic Prescriptions in Noida,
India. (Thesis). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:733487/
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):
Rawat, Aditi. “Prescriptions, Perceptions and Resistance - A Qualitative
Study of Public Perceptions of Antibiotic Prescriptions in Noida,
India.” 2017. Thesis, Brown University. Accessed February 27, 2020.
https://repository.library.brown.edu/studio/item/bdr:733487/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rawat, Aditi. “Prescriptions, Perceptions and Resistance - A Qualitative
Study of Public Perceptions of Antibiotic Prescriptions in Noida,
India.” 2017. Web. 27 Feb 2020.
Vancouver:
Rawat A. Prescriptions, Perceptions and Resistance - A Qualitative
Study of Public Perceptions of Antibiotic Prescriptions in Noida,
India. [Internet] [Thesis]. Brown University; 2017. [cited 2020 Feb 27].
Available from: https://repository.library.brown.edu/studio/item/bdr:733487/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rawat A. Prescriptions, Perceptions and Resistance - A Qualitative
Study of Public Perceptions of Antibiotic Prescriptions in Noida,
India. [Thesis]. Brown University; 2017. Available from: https://repository.library.brown.edu/studio/item/bdr:733487/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
11.
Wong, Neelum.
Development of Improved Chemotherapeutics in Pancreatic and
Colorectal Cancer: Ceramide as a Potential Adjuvant with Sigma-2
Receptor Ligands.
Degree: Department of Molecular Pharmacology, Physiology and
Biotechnology, 2018, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:792844/
► Pancreatic and colorectal cancer are highly aggressive and challenging to treat. Both cancers have low survival rates and there is a need for more elaborate…
(more)
▼ Pancreatic and colorectal cancer are highly aggressive
and challenging to treat. Both cancers have low survival rates and
there is a need for more elaborate therapies as patients suffer
from drug
resistance to commonly used chemotherapeutics. The
difficulty in finding novel and effective treatments has led
researchers to explore the sigma-2 receptor and the sphingolipid
ceramide for their roles in inducing apoptosis in cancer cells.
Ceramide has recently been studied for its ability to potentiate
chemotherapeutics for pancreatic and colorectal cancer patients
with a mutation in the KRAS oncogene that contributes to drug
resistance. The sigma-2 receptor is upregulated in cancer cells and
a cytotoxic response by the activation of the receptor in cancer
cells is a property that can be exploited in the attempt to
overcome drug
resistance and kill pancreatic and colorectal cancer
cells. Here, the cytotoxicity of C-6 ceramide on cell viability for
PANC-1, MIA PaCA-2, and L3.6 pancreatic cancer cell lines and
KRAS-wild-type SW48 and KRAS-mutated SW480 colorectal cell lines
was found using the MTT cell viability assay. Additionally, this
study revealed that a combination treatment of C-6 ceramide with
the sigma-2 receptor agonists, siramesine and SV119 had a
synergistic effect on cytotoxicity while C-6 ceramide with the
sigma-2 receptor agonist, MAM03055A had an additive effect on the
colorectal cancer cell lines. Interestingly, no difference in
cytotoxicity was observed in the combination therapy treatments
between the KRAS-wild-type and KRAS-mutated cell lines. Altogether,
this data suggests that a combination treatment of ceramide with
sigma-2 receptor agonists is promising for the development of
improved chemotherapeutics for pancreatic and colorectal
cancer.
Advisors/Committee Members: Mathiowitz, Edith (Reader), Morgan, Jeffrey (Reader), Bowen, Wayne (Advisor).
Subjects/Keywords: Drug resistance
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CSE |
Export
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Manager
APA (6th Edition):
Wong, N. (2018). Development of Improved Chemotherapeutics in Pancreatic and
Colorectal Cancer: Ceramide as a Potential Adjuvant with Sigma-2
Receptor Ligands. (Thesis). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:792844/
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):
Wong, Neelum. “Development of Improved Chemotherapeutics in Pancreatic and
Colorectal Cancer: Ceramide as a Potential Adjuvant with Sigma-2
Receptor Ligands.” 2018. Thesis, Brown University. Accessed February 27, 2020.
https://repository.library.brown.edu/studio/item/bdr:792844/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wong, Neelum. “Development of Improved Chemotherapeutics in Pancreatic and
Colorectal Cancer: Ceramide as a Potential Adjuvant with Sigma-2
Receptor Ligands.” 2018. Web. 27 Feb 2020.
Vancouver:
Wong N. Development of Improved Chemotherapeutics in Pancreatic and
Colorectal Cancer: Ceramide as a Potential Adjuvant with Sigma-2
Receptor Ligands. [Internet] [Thesis]. Brown University; 2018. [cited 2020 Feb 27].
Available from: https://repository.library.brown.edu/studio/item/bdr:792844/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wong N. Development of Improved Chemotherapeutics in Pancreatic and
Colorectal Cancer: Ceramide as a Potential Adjuvant with Sigma-2
Receptor Ligands. [Thesis]. Brown University; 2018. Available from: https://repository.library.brown.edu/studio/item/bdr:792844/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
12.
Durmus, Naside Gozde.
Enhanced Efficacy of Nanotechnology-Driven Approaches
against Antibiotic-Resistant Biofilms in the Presence of
Metabolites.
Degree: PhD, Biomedical Engineering, 2013, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:320579/
► Antibiotic resistance and the lack of new antimicrobial therapies create significant challenges for the treatment of infections. Therefore, there is an urgent clinical need to…
(more)
▼ Antibiotic
resistance and the lack of new
antimicrobial therapies create significant challenges for the
treatment of infections. Therefore, there is an urgent clinical
need to develop novel treatments targeting bacterial biofilms to
reduce the risk of infection, without resorting to antibiotics. The
goal of this thesis is, for the first time, to integrate two novel
approaches, i.e. nanotechnology and metabolic stimulation, to
eradicate antibiotic-resistant biofilms. The metabolic
microenvironment of the biofilms has been manipulated to improve
the antibacterial properties of superparamagnetic iron oxide
nanoparticles (SPION) as well as nanorough device surfaces. First,
it has been shown that engineered nanoscale topographies provide
surfaces that are more resistant to bacterial growth than
conventional polyvinyl chloride (PVC). In addition, for the first
time, the presence of fructose on the nanorough PVC further
decreased the planktonic S. aureus growth and biofilm formation,
without use of any antibiotics. Moreover, a simple, broad-spectrum
and low-cost dual-sided approach which uses SPION in combination
with metabolites (i.e., fructose, glucose, and mannitol) has been
developed as an alternative to existing antibacterial strategies.
This strategy offers further improved efficacy of SPION against
persistent gram-positive and gram-negative bacteria infections by
manipulating the biofilm metabolic microenvironment, creating a new
nanotechnology-driven approach. Further, biofilm eradication by the
engineered SPION was significantly better than vancomycin, the
antibiotic of last resort. In addition, it has been demonstrated
that SPION conjugated with antibacterial silver salts exhibit
strong eradication properties against the antibiotic-resistant
(MRSA) biofilms. Antibacterial properties of silver-conjugated
SPION were further improved when an external magnetic field was
applied as their magnetic core enabled them to penetrate into the
biofilms. This thesis, for the first time, highlighted the
importance of biofilm metabolic microenvironment for the
nanotechnology-driven approaches. It is envisioned that these
simple and inexpensive approaches could lead to novel alternative
treatments to the only current clinical option, vancomycin, which
MRSA has started to develop a
resistance towards. These novel
nanotechnology-driven approaches can lead to successful clinical
outcomes in terms of minimizing infections, longer medical device
lifetimes, and decreasing antibiotic usage.
Advisors/Committee Members: Webster, Thomas (Director), Webster, Thomas (Reader), Tripathi, Anubhav (Reader), Sun, Shouheng (Reader), Morgan, Jeffrey (Reader), Tripathi, Anubhav (Director).
Subjects/Keywords: antibiotic resistance
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Durmus, N. G. (2013). Enhanced Efficacy of Nanotechnology-Driven Approaches
against Antibiotic-Resistant Biofilms in the Presence of
Metabolites. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:320579/
Chicago Manual of Style (16th Edition):
Durmus, Naside Gozde. “Enhanced Efficacy of Nanotechnology-Driven Approaches
against Antibiotic-Resistant Biofilms in the Presence of
Metabolites.” 2013. Doctoral Dissertation, Brown University. Accessed February 27, 2020.
https://repository.library.brown.edu/studio/item/bdr:320579/.
MLA Handbook (7th Edition):
Durmus, Naside Gozde. “Enhanced Efficacy of Nanotechnology-Driven Approaches
against Antibiotic-Resistant Biofilms in the Presence of
Metabolites.” 2013. Web. 27 Feb 2020.
Vancouver:
Durmus NG. Enhanced Efficacy of Nanotechnology-Driven Approaches
against Antibiotic-Resistant Biofilms in the Presence of
Metabolites. [Internet] [Doctoral dissertation]. Brown University; 2013. [cited 2020 Feb 27].
Available from: https://repository.library.brown.edu/studio/item/bdr:320579/.
Council of Science Editors:
Durmus NG. Enhanced Efficacy of Nanotechnology-Driven Approaches
against Antibiotic-Resistant Biofilms in the Presence of
Metabolites. [Doctoral Dissertation]. Brown University; 2013. Available from: https://repository.library.brown.edu/studio/item/bdr:320579/
13.
Vecchione, James J.
Using Chemical, Genetic, and Biochemical Approaches to
Understand and Circumvent Antibacterial Drug Resistance.
Degree: PhD, Chemistry, 2011, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:11186/
► The growing number of drug-resistant pathogenic bacteria is an impending public health crisis. Unfortunately, the rate at which pathogenic bacteria are developing resistance to our…
(more)
▼ The growing number of drug-resistant pathogenic
bacteria is an impending public health crisis. Unfortunately, the
rate at which pathogenic bacteria are developing
resistance to our
existing battery of anti-infective drugs is greater than the rate
at which new drugs are being developed. We pursued two
complementary strategies to address the problem of antibacterial
resistance. Firstly, we studied
resistance to indolmycin, a member
of a promising class of antibiotics known as the aminoacyl-tRNA
synthetase inhibitors. To elucidate the potential clinical utility
of indolmycin, we analyzed innate mechanisms of
resistance in
Streptomyces bacteria and assessed the distribution of indolmycin
resistance genes in the genomes of various bacterial genera. Our
combined genetic, biochemical, and bioinformatic approaches yielded
insights that are relevant to the development of aminoacyl-tRNA
synthetase inhibitors as antibacterial drugs. Secondly, we studied
ways to deactivate or circumvent antibiotic
resistance mechanisms
in bacteria. In particular, we demonstrated that indolmycin can
suppress multi-drug
resistance phenotypes via perturbation of
protein synthesis and showed that C-capped dipeptides can
potentiate the activity of chloramphenicol via inhibition of major
facilitator superfamily drug efflux pumps.
Advisors/Committee Members: Sello, Jason (Director), Suggs, J. William (Reader), Seto, Christopher (Reader).
Subjects/Keywords: Antibiotic Resistance
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APA (6th Edition):
Vecchione, J. J. (2011). Using Chemical, Genetic, and Biochemical Approaches to
Understand and Circumvent Antibacterial Drug Resistance. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:11186/
Chicago Manual of Style (16th Edition):
Vecchione, James J. “Using Chemical, Genetic, and Biochemical Approaches to
Understand and Circumvent Antibacterial Drug Resistance.” 2011. Doctoral Dissertation, Brown University. Accessed February 27, 2020.
https://repository.library.brown.edu/studio/item/bdr:11186/.
MLA Handbook (7th Edition):
Vecchione, James J. “Using Chemical, Genetic, and Biochemical Approaches to
Understand and Circumvent Antibacterial Drug Resistance.” 2011. Web. 27 Feb 2020.
Vancouver:
Vecchione JJ. Using Chemical, Genetic, and Biochemical Approaches to
Understand and Circumvent Antibacterial Drug Resistance. [Internet] [Doctoral dissertation]. Brown University; 2011. [cited 2020 Feb 27].
Available from: https://repository.library.brown.edu/studio/item/bdr:11186/.
Council of Science Editors:
Vecchione JJ. Using Chemical, Genetic, and Biochemical Approaches to
Understand and Circumvent Antibacterial Drug Resistance. [Doctoral Dissertation]. Brown University; 2011. Available from: https://repository.library.brown.edu/studio/item/bdr:11186/
University of Florida
14.
Yuan, Weimin.
Evaluation of Resistance to Meloidogyne Arenaria in the Peanut (Arachis Hypogaea. L) Cv. Tifguard.
Degree: PhD, Entomology and Nematology, 2017, University of Florida
URL: http://ufdc.ufl.edu/UFE0050637
► Tifguard, which was released as a peanut cultivar resistant to root-knot nematode and tomato spotted wilt virus in 2007, was found to be heavily infected…
(more)
▼ Tifguard, which was released as a peanut cultivar resistant to root-knot nematode and tomato spotted wilt virus in 2007, was found to be heavily infected by Meloidogyne arenaria in several peanut production fields in Florida in 2012. The goal of this project was to determine why the cultivar that was reported to be highly resistant succumbed to root-knot nematode infection. The objectives were to evaluate the
resistance of three different sources of Tifguard seeds; to determine the seasonal population changes and vertical population densities of M. arenaria collected from resistant and susceptible peanut rhizospheres in two different soil types; to determine the effects of high temperature on the
resistance in Tifguard, and to compare the yield of Tifguard, isogenic Tifguard and Georgia-06G treated vs. nontreated with 1,3-dichloropropene. In three M. arenaria infested field sites, a comparison of Tifguard seed obtained from three sources showed that 2.5, 28, and 39.5% of plants that were infected by the nematode were negative for the nematode
resistance gene. The seasonal distribution of second-stage juvenile (J2) of M. arenaria followed similar trends in two different soil types, with a peak occurring during late summer and early fall at harvest. Number of J2 dropped following harvest and reached a density less than 10 J2/200 cm3 of soil in February. Comparison of vertical population densities of J2 collected from Georgia-06G rhizosphere in two different soil types showed that greater numbers occurred in the upper 60 cm of soil during the growing season in a Candler sand, whereas in a Norfolk loamy sand greater densities were found only in the top 45 cm. The population densities of J2 collected from Georgia-06G rhizosphere at all depths were much greater in Norfolk loamy sand than that in the Candler sand. Tifguard reduced the nematode population to 1 and 28 in the Candler sand and the Norfolk loamy sand, respectively at harvest. Comparison of nematode numbers from different developmental stages at different temperatures demonstrated that the high soil temperature increased nematode infection rate and accelerated nematode development in Georgia-06G. No further development of J2 occurred in Tifguard roots at 28 or 31 C, however at 34 C a few J3-J4, females, egg laying females, and males of M. arenaria were observed. Comparisons indicated that there was no effect of 1,3-dichloropropene on root-knot nematode damage and yield of Georgia-06G, Tifguard, or isogenic Tifguard. ( en )
Advisors/Committee Members: DICKSON,DONALD W (committee chair), BRITO,JANETE A (committee member), PRESTON,JAMES F,III (committee member).
Subjects/Keywords: resistance – tifguard
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Manager
APA (6th Edition):
Yuan, W. (2017). Evaluation of Resistance to Meloidogyne Arenaria in the Peanut (Arachis Hypogaea. L) Cv. Tifguard. (Doctoral Dissertation). University of Florida. Retrieved from http://ufdc.ufl.edu/UFE0050637
Chicago Manual of Style (16th Edition):
Yuan, Weimin. “Evaluation of Resistance to Meloidogyne Arenaria in the Peanut (Arachis Hypogaea. L) Cv. Tifguard.” 2017. Doctoral Dissertation, University of Florida. Accessed February 27, 2020.
http://ufdc.ufl.edu/UFE0050637.
MLA Handbook (7th Edition):
Yuan, Weimin. “Evaluation of Resistance to Meloidogyne Arenaria in the Peanut (Arachis Hypogaea. L) Cv. Tifguard.” 2017. Web. 27 Feb 2020.
Vancouver:
Yuan W. Evaluation of Resistance to Meloidogyne Arenaria in the Peanut (Arachis Hypogaea. L) Cv. Tifguard. [Internet] [Doctoral dissertation]. University of Florida; 2017. [cited 2020 Feb 27].
Available from: http://ufdc.ufl.edu/UFE0050637.
Council of Science Editors:
Yuan W. Evaluation of Resistance to Meloidogyne Arenaria in the Peanut (Arachis Hypogaea. L) Cv. Tifguard. [Doctoral Dissertation]. University of Florida; 2017. Available from: http://ufdc.ufl.edu/UFE0050637
15.
Martin, Jacob Leeds.
Perceived dominant group exclusion and resistance: a look at potential leadership remedies.
Degree: MS, Psychology, 2012, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201212_ms
► Using a large sample of employees from a Midwestern healthcare organization, this study examines perceived exclusion by dominant group members in a multicultural context. Specifically,…
(more)
▼ Using a large sample of employees from a Midwestern healthcare organization, this study examines perceived exclusion by dominant group members in a multicultural context. Specifically, this study recognizes diversity
resistance as a potential concern for perceived exclusion in multicultural organizations. Leadership remedies such as role modeling diversity practices and communication are explored as behaviors to mitigate exclusion perceptions. Finally, departmental diversity values are tested as a moderator to understand contextual factors which may impact these leadership remedies’ success. Findings indicate that both leadership behaviors are associated with an increased sense of inclusion among dominant group members, which subsequently shows to be related to increased employee engagement. Furthermore, departmental values of diversity did impact the effectiveness of communication behaviors by leaders. This study highlights dominant group exclusion as a potential indicator of
resistance, and offers support for leader behaviors which may remedy this increasingly important issue.
Advisors/Committee Members: Karl Kuhnert.
Subjects/Keywords: Resistance
…particularly by
dominant group members. Thomas and Plaut (2008) explore resistance to… …and
detrimental impact of resistance to diversity initiatives in multicultural organizations… …impact of this
increased sense of inclusion could result in less resistance to such… …in the
workplace have been met with resistance, largely tied to dominant group feelings of… …multiculturalism.
Resistance to Diversity
Dominant Group Resistance to Multicultural Systems
With the…
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APA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Martin, J. L. (2012). Perceived dominant group exclusion and resistance: a look at potential leadership remedies. (Masters Thesis). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201212_ms
Chicago Manual of Style (16th Edition):
Martin, Jacob Leeds. “Perceived dominant group exclusion and resistance: a look at potential leadership remedies.” 2012. Masters Thesis, University of Georgia. Accessed February 27, 2020.
http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201212_ms.
MLA Handbook (7th Edition):
Martin, Jacob Leeds. “Perceived dominant group exclusion and resistance: a look at potential leadership remedies.” 2012. Web. 27 Feb 2020.
Vancouver:
Martin JL. Perceived dominant group exclusion and resistance: a look at potential leadership remedies. [Internet] [Masters thesis]. University of Georgia; 2012. [cited 2020 Feb 27].
Available from: http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201212_ms.
Council of Science Editors:
Martin JL. Perceived dominant group exclusion and resistance: a look at potential leadership remedies. [Masters Thesis]. University of Georgia; 2012. Available from: http://purl.galileo.usg.edu/uga_etd/martin_jacob_l_201212_ms
University of Debrecen
16.
Tosin, Ogungbemile.
Employee resistance towards organizational changes
.
Degree: DE – TEK – Közgazdaság- és Gazdaségtudományi Kar, 2011, University of Debrecen
URL: http://hdl.handle.net/2437/118063
► I want to show my sincere gratitude to all those who made this study possible. First of all, i am very thankful to the helpful…
(more)
▼ I want to show my sincere gratitude to all those who made this study possible. First of all, i am very thankful to the helpful staff of University OF Debrecen. One of the most important tasks in every good study is its critical evaluation and feedback which was performed by my supervisor Eniko szilagyi. I am are very thankful to my supervisor for investing her precious time to discuss and criticize this study in depth, and explained the meaning of different concepts . All this, made my tasks very interesting and challenging to me, it also provided me an opportunity to remove any flaws and weaknesses. A warm thanks to Mr Sola who provided me guidance on how to start. I also want to appreciate the efforts of all the staff, senior managements and owner of the firm understudy, who so openly and warmly welcomed me to use previous observations and take in-depth interviews and discussions about the work. My sincere thanks goes to my family members, who indirectly participated in this study by encouraging and supporting me.
Advisors/Committee Members: Szilagyi, Eniko (advisor).
Subjects/Keywords: employee resistance
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Manager
APA (6th Edition):
Tosin, O. (2011). Employee resistance towards organizational changes
. (Thesis). University of Debrecen. Retrieved from http://hdl.handle.net/2437/118063
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):
Tosin, Ogungbemile. “Employee resistance towards organizational changes
.” 2011. Thesis, University of Debrecen. Accessed February 27, 2020.
http://hdl.handle.net/2437/118063.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tosin, Ogungbemile. “Employee resistance towards organizational changes
.” 2011. Web. 27 Feb 2020.
Vancouver:
Tosin O. Employee resistance towards organizational changes
. [Internet] [Thesis]. University of Debrecen; 2011. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/2437/118063.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tosin O. Employee resistance towards organizational changes
. [Thesis]. University of Debrecen; 2011. Available from: http://hdl.handle.net/2437/118063
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Manitoba
17.
Wierzbowski, Aleksandra K.
Evolution and molecular characterization of clinical respiratory macrolide-resistant Streptococcus pneumoniae in Canada.
Degree: Medical Microbiology, 2012, University of Manitoba
URL: http://hdl.handle.net/1993/5072
► The purpose of this thesis was to molecularly characterize macrolide-resistant S. pneumoniae (SPN) isolates in Canada between 1998 and 2008. The characterization involved looking at…
(more)
▼ The purpose of this thesis was to molecularly characterize macrolide-resistant S. pneumoniae (SPN) isolates in Canada between 1998 and 2008. The characterization involved looking at the multi-drug resistant phenotype (MDR), the mechanisms of macrolide
resistance, the genetic relatedness, the serotype distribution and PCV7 vaccine coverage as well as the determination of presence of pili-virulence factors. The hypothesis of the study was that macrolide-resistant SPN will growingly be MDR, genetically related, piliated and consisting of serotypes not found in PCV7 vaccine.
Over 1500 macrolide-resistant SPN isolates collected between 1998 and 2008 were studied. Macrolide-resistant isolates came from patients from all regions of Canada, and from all age groups. They came from slightly more males (60%) and slightly more in-patients (62%). Macrolide resistant SPN remained low at 8% during the first 4 years of the study, and started to increase reaching 22% by the end of the study in 2008 (p=0.001). Overall the most common mechanism of
resistance was efflux mediated by mef(A) (51%), followed by target site modification mediated by erm(B) (36%). The efflux mediated macrolide
resistance in S. pneumoniae was predominantly due to the presence of subtype E (95%), which was resistant to more antibiotic classes, and was genetically and serotypically more diverse than the A subtype. Isolates carrying both erm(B) and mef(A) macrolide
resistance genes increased overtime from 1% (1998) to 19% (2008) (p=0.002). Serotype distribution showed a decrease in PCV7 vaccine coverage from 67% to 31% (p=0.0072). Isolates with non-PCV7 serotypes increased overtime from 33% to 57% (p=0.0152).
Isolates with serotype 19A increased by 15% (p=0.005). They were found to be multi-drug resistant, carried both erm(B) and mef(A) subtype E macrolide
resistance genes, and were genetically related. The presence of virulence factor pili-type 1 (PI-1) and pili-type 2 (PI-2) was found associated with these isolates, possibly contributing to its emergence. In conclusion, macrolide resistant SPN increased during the course of this study mostly due to emergence of multi-drug resistant, genetically related, piliated, 19A S. pneumoniae.
Advisors/Committee Members: Zhanel, George (Medical Microbiology) (supervisor), Embree, Joanne (Medical Microbiology) Worobec, Elizabeth (Microbiology) Mulvey, Michael (Medical Microbiology) Hoban, Daryl (Medical Microbiology) Farrell, David (JMI Laboratories) (examiningcommittee).
Subjects/Keywords: Resistance; Macrolides
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APA (6th Edition):
Wierzbowski, A. K. (2012). Evolution and molecular characterization of clinical respiratory macrolide-resistant Streptococcus pneumoniae in Canada. (Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/5072
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):
Wierzbowski, Aleksandra K. “Evolution and molecular characterization of clinical respiratory macrolide-resistant Streptococcus pneumoniae in Canada.” 2012. Thesis, University of Manitoba. Accessed February 27, 2020.
http://hdl.handle.net/1993/5072.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wierzbowski, Aleksandra K. “Evolution and molecular characterization of clinical respiratory macrolide-resistant Streptococcus pneumoniae in Canada.” 2012. Web. 27 Feb 2020.
Vancouver:
Wierzbowski AK. Evolution and molecular characterization of clinical respiratory macrolide-resistant Streptococcus pneumoniae in Canada. [Internet] [Thesis]. University of Manitoba; 2012. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/1993/5072.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wierzbowski AK. Evolution and molecular characterization of clinical respiratory macrolide-resistant Streptococcus pneumoniae in Canada. [Thesis]. University of Manitoba; 2012. Available from: http://hdl.handle.net/1993/5072
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Manitoba
18.
Wang, Duoduo.
Transferring blackleg resistance from Brassica carinata and synthetic hexaploid Brassica accessions into Brassica napus.
Degree: Plant Science, 2016, University of Manitoba
URL: http://hdl.handle.net/1993/31196
► Blackleg caused by Leptosphaeria maculans (Desm.) Ces. & De Not. is one of the most serious diseases in canola production. A high level of blackleg…
(more)
▼ Blackleg caused by Leptosphaeria maculans (Desm.) Ces. & De Not. is one of the most serious diseases in canola production. A high level of blackleg
resistance has been shown in Brassica carinata A. Braun (BBCC) and new synthetic hexaploid Brassica species (AABBCC) developed from the crosses of B. rapa L. and B. carinata. Blackleg
resistance from B. carinata and hexaploid Brassica accessions was transferred into B. napus L. using interspecific hybridization followed by backcrossing to a susceptible B. napus cultivar ‘Westar’ three or four times and selfing one or two times to produce pure lines. Leptosphaeria maculans isolate 03-15-03 was used to select the resistant plants in each generation using cotyledon inoculation, and four L. maculans isolates (03-15-03, 3-42-6, 09stonewall9553, and PG4-1-M) were utilized in advanced generations. In the cross of B. napus ‘Westar’ and B. carinata, all plants in the F1 showed a high level of
resistance to L. maculans isolate 03-15-03. According to the chi-square testing for goodness of fit, the segregation of resistant and susceptible plants fit a 1:1 ratio in the BC1, BC3, and BC4. In the BC3F2, two families followed a 3:1 segregation ratio of resistant and susceptible plants. The results suggest that the
resistance to L. maculans transferred from B. carinata into canola ‘Westar’ was controlled by a single locus.
Embryo rescue tissue culture was used to obtain F1 plants of the crosses of ‘Westar’ and synthetic hexaploid Brassica accessions. In the BC1 and BC2, most families did not fit a 1:1 segregation ratio of resistant and susceptible plants. The segregation of resistant and susceptible plants fit a 3:1 ratio when inoculated with L. maculans isolates in the BC1F2-3.1.1s and BC1F3-3.1.1.1ss families. Meanwhile, the BC2-3.1.1 family also followed a 1:1 segregation of resistant and susceptible plants inoculated with L. maculans isolate 03-15-03. The results suggest that the
resistance to L. maculans introgressed from synthetic hexaploid Brassica species into B. napus is most likely controlled by a single locus.
Advisors/Committee Members: Genyi Li (Plant Science) (supervisor), Robert Duncan (Plant science) Thomas Booth (Biological sciences) (examiningcommittee).
Subjects/Keywords: blackleg resistance
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APA (6th Edition):
Wang, D. (2016). Transferring blackleg resistance from Brassica carinata and synthetic hexaploid Brassica accessions into Brassica napus. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/31196
Chicago Manual of Style (16th Edition):
Wang, Duoduo. “Transferring blackleg resistance from Brassica carinata and synthetic hexaploid Brassica accessions into Brassica napus.” 2016. Masters Thesis, University of Manitoba. Accessed February 27, 2020.
http://hdl.handle.net/1993/31196.
MLA Handbook (7th Edition):
Wang, Duoduo. “Transferring blackleg resistance from Brassica carinata and synthetic hexaploid Brassica accessions into Brassica napus.” 2016. Web. 27 Feb 2020.
Vancouver:
Wang D. Transferring blackleg resistance from Brassica carinata and synthetic hexaploid Brassica accessions into Brassica napus. [Internet] [Masters thesis]. University of Manitoba; 2016. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/1993/31196.
Council of Science Editors:
Wang D. Transferring blackleg resistance from Brassica carinata and synthetic hexaploid Brassica accessions into Brassica napus. [Masters Thesis]. University of Manitoba; 2016. Available from: http://hdl.handle.net/1993/31196
19.
García Cazorla, Yolanda.
Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos.
Degree: 2018, Universidad de Cantabria
URL: http://hdl.handle.net/10902/14718
► ABSTRACT: Antibiotic resistance has become a pressing public health concern. The main mechanism for the dissemination of resistance genes is the horizontal transfer during conjugation.…
(more)
▼ ABSTRACT: Antibiotic
resistance has become a pressing public health concern. The main mechanism for the dissemination of
resistance genes is the horizontal transfer during conjugation. Hence, the search for conjugation inhibitors (COINs) is paramount in the fight against the spread of resistances. In this pursuit, only unsaturated fatty acids had been described as COINs. Here, we define 2-bromopalmitic acid (2-BP) as a specific COIN. 2-BP is a palmitate analog without any unsaturation in its aliphatic chain which acts as inhibitor of many membrane-associated enzymes. The carboxylic group of COINs is essential for its effectivity. However, inhibition is not due to the presence of double or triple bonds in these compounds but, indirectly, by the conformation COINs can acquire upon binding to their molecular target.
We identify the VirB11 homolog in the conjugative plasmid R388, the traffic ATPase TrwD, as their molecular target. VirB11 form hexameric rings in which each monomer has a C-terminal catalytic region (CTD) and a N-terminal region that interacts with the cytoplasmic site of the membrane (NTD) connected both of them by a flexible linker. Biochemical and structural characterizations define a non-competitive inhibition where COINs bind to a pocket comprised by NTD and linker, preventing the pivoting movement of NTD over CTD which, in turn, result in a reduction of TrwD ATPase activity. Interestingly, COINs are liberally incorporated into bacterial membranes, replacing palmitic acid as the major component. We determine that TrwD binds palmitic acid, thus facilitating its interaction with the membrane. Altogether, our data suggest that COINs bind TrwD at a site that is otherwise occupied by palmitic acid, albeit they differ in the contacts involved in the interaction. As a result, COINs affect the interaction of TrwD with the membrane.
For a further understand of the conjugative process, we visualized the process in real time using fluorescent protein fusions to the main players in the conjugative system. Localization of the proteins suffers dramatic changes in the presence or absence of the rest of the component of the Type IV secretion system (T4SS). Moreover, by using fluorescent constructs of SeqA, a probe that binds hemimethylated DNA, we have found, surprisingly, that more than one event of conjugation takes place at a particular time. Additionally, we identify the formation of a weak complex between TrwD and the relaxase TrwC. TrwD presents structural homology to chaperones of the ClpB/Hsp 104 family, hence TrwD could play a chaperone activity during the transport of the pilot protein TrwC.
In short, our results do not only contribute to a better understanding of VirB11 proteins and the conjugative process but also may open a new avenue for the rational design of more potent and effective drugs to control dissemination of antibiotic
resistance genes.
Advisors/Committee Members: Cabezón Navarro, María Elena (advisor), Universidad de Cantabria (other).
Subjects/Keywords: Antibiotic resistance
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APA (6th Edition):
García Cazorla, Y. (2018). Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos. (Doctoral Dissertation). Universidad de Cantabria. Retrieved from http://hdl.handle.net/10902/14718
Chicago Manual of Style (16th Edition):
García Cazorla, Yolanda. “Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos.” 2018. Doctoral Dissertation, Universidad de Cantabria. Accessed February 27, 2020.
http://hdl.handle.net/10902/14718.
MLA Handbook (7th Edition):
García Cazorla, Yolanda. “Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos.” 2018. Web. 27 Feb 2020.
Vancouver:
García Cazorla Y. Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos. [Internet] [Doctoral dissertation]. Universidad de Cantabria; 2018. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/10902/14718.
Council of Science Editors:
García Cazorla Y. Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos. [Doctoral Dissertation]. Universidad de Cantabria; 2018. Available from: http://hdl.handle.net/10902/14718
University of Hawaii – Manoa
20.
Caprio, Michael A.
Gene flow as a factor in the evolution of insecticide resistance.
Degree: PhD, 2009, University of Hawaii – Manoa
URL: http://hdl.handle.net/10125/9768
► Typescript.
Microfiche.
xiii, 114 leaves, bound ill. 29 cm
The importance of gene flow in maintaining genetic variation among local populations in heterogeneous habitats has…
(more)
▼ Typescript.
Microfiche.
xiii, 114 leaves, bound ill. 29 cm
The importance of gene flow in maintaining genetic variation among local populations in heterogeneous habitats has been debated for natural populations as well as populations subject to selection in manipulated ecosystems such as agricultural fields. The diamondback moth, Plutella xylostella (L.), is a pest of cruciferous crops and frequently treated with insecticides. Despite the high dispersal capabilities of this moth, considerable local variation exists in its response to insecticides, suggesting that gene flow among subpopulations may be restricted. The central question addressed by this study is whether this local variation is due to restricted gene flow, or if variation in selection due to different pesticide strategies is sufficient to maintain the variation. Electrophoretic measurements of allozyme variation among 11 subpopulations on three islands in Hawaii indicate small amounts of genetic differentiation between subpopulations (overall FST estimates ranged from 0.038 to 0.028). This suggests that roughly 8 migrants are exchanged per subpopulation per generation. Smaller amounts of differentiation were observed between islands and between Hawaii and two continental populations, perhaps because insufficient time has passed for these larger population subunits to differentiate via drift. Simulation of resistance evolution among treated and untreated fields in the diamondback moth suggests that migration rates greater than 10% are required before emigration from untreated into treated fields will delay resistance evolution. Low rates of gene flow (<0.1%) delayed the overall rate of resistance evolution when resistance alleles were rare initially. The fastest rates of resistance evolution occurred at intermediate gene flow rates. The effect of gene flow on the establishment of a pesticide resistant parasitoid, Trioxys pallidus, is examined in Chapter 3. Increased migration, either by dividing the number of resistant parasitoids released into smaller groups, or by increasing the migration rate, decreased the time required to implement the new strain. The simulations indicate that at least three years will be required for establishment of the resistant strain. The results demonstrate that implementation of genetically altered insects may require a significant proportion of the time allocated to a genetic manipulation project. Studies to identify potential problems in the implementation phase should be part of the initial consideration of any such project.
Subjects/Keywords: Moths – Insecticide resistance; Plutellidae – Insecticide resistance
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APA (6th Edition):
Caprio, M. A. (2009). Gene flow as a factor in the evolution of insecticide resistance. (Doctoral Dissertation). University of Hawaii – Manoa. Retrieved from http://hdl.handle.net/10125/9768
Chicago Manual of Style (16th Edition):
Caprio, Michael A. “Gene flow as a factor in the evolution of insecticide resistance.” 2009. Doctoral Dissertation, University of Hawaii – Manoa. Accessed February 27, 2020.
http://hdl.handle.net/10125/9768.
MLA Handbook (7th Edition):
Caprio, Michael A. “Gene flow as a factor in the evolution of insecticide resistance.” 2009. Web. 27 Feb 2020.
Vancouver:
Caprio MA. Gene flow as a factor in the evolution of insecticide resistance. [Internet] [Doctoral dissertation]. University of Hawaii – Manoa; 2009. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/10125/9768.
Council of Science Editors:
Caprio MA. Gene flow as a factor in the evolution of insecticide resistance. [Doctoral Dissertation]. University of Hawaii – Manoa; 2009. Available from: http://hdl.handle.net/10125/9768
Penn State University
21.
Jiao, Qianning.
Castration causes insulin but not leucine resistance in male
rats.
Degree: MS, Physiology, 2009, Penn State University
URL: https://etda.libraries.psu.edu/catalog/9660
► Testosterone has long been reported to have anabolic effects. Low concentrations of plasma testosterone have been associated with insulin resistance, which is an important upstream…
(more)
▼ Testosterone has long been reported to have anabolic
effects. Low concentrations of plasma testosterone have been
associated with insulin resistance, which is an important upstream
driver for metabolic abnormalities such as hyperglycemia,
hypertension, or hyperlipidemia, and increased cardiovascular risk.
The purpose of this thesis is to test the hypothesis that lack of
testosterone also impairs the anabolic response to amino acids,
specifically leucine (Leu), which stimulates protein synthesis
through mammalian target of rapamycin (mTOR) pathway. 6- week old
castrated rats were measured body composition in a 9-week period,
during which a glucose tolerance test was performed to confirm that
low testosterone leads to insulin resistance. Compared to control
rats, a decrease in both body weight and lean body mass was
observed in castrated animals. After that, Leu or saline (Sal) was
administered to castrated and time-matched control rats. The
gastrocnemius and liver were removed 20 min later for assessment of
protein synthesis and signaling components important in
peptide-chain initiation. No change in the ability of leucine to
induce phosphorylation of eukaryotic initiation factor (eIF)
4E-binding protein 1 (4E-BP1) and ribosomal protein S6 kinase 1
(S6K1) was observed. Both protein synthesis and degradation rate
did not change significantly in castrated rats. The decrease in
lean body mass cannot be attributed to changes in protein
degradation rate, and it is possible that low mTOR activity and
protein synthesis rate induced by castration is responsible for the
erosion of muscle mass. Castration does not change the effect of
leucine to induce 4E-BP1 and S6K1 phosphorylation, hence,
castration may influence anabolic physiological processes by
influencing upstream signals of mTOR, which are independent of the
insulin signaling pathway.
Subjects/Keywords: insulin resistance; castration; testosterone; leucine
resistance
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APA ·
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APA (6th Edition):
Jiao, Q. (2009). Castration causes insulin but not leucine resistance in male
rats. (Masters Thesis). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/9660
Chicago Manual of Style (16th Edition):
Jiao, Qianning. “Castration causes insulin but not leucine resistance in male
rats.” 2009. Masters Thesis, Penn State University. Accessed February 27, 2020.
https://etda.libraries.psu.edu/catalog/9660.
MLA Handbook (7th Edition):
Jiao, Qianning. “Castration causes insulin but not leucine resistance in male
rats.” 2009. Web. 27 Feb 2020.
Vancouver:
Jiao Q. Castration causes insulin but not leucine resistance in male
rats. [Internet] [Masters thesis]. Penn State University; 2009. [cited 2020 Feb 27].
Available from: https://etda.libraries.psu.edu/catalog/9660.
Council of Science Editors:
Jiao Q. Castration causes insulin but not leucine resistance in male
rats. [Masters Thesis]. Penn State University; 2009. Available from: https://etda.libraries.psu.edu/catalog/9660
University of Cambridge
22.
Rowe, Will.
Antimicrobial resistance gene monitoring in aquatic environments.
Degree: PhD, 2016, University of Cambridge
URL: https://www.repository.cam.ac.uk/handle/1810/253755
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683707
► This dissertation documents the development of an environmental framework for monitoring antimicrobial resistance gene (ARG) dissemination in the aquatic environment. The work opens with a…
(more)
▼ This dissertation documents the development of an environmental framework for monitoring antimicrobial resistance gene (ARG) dissemination in the aquatic environment. The work opens with a review of the relevant literature and outlines the importance of an environmental framework for monitoring ARG dissemination as part of antimicrobial resistance risk assessments. The ability to interrogate sequencing data quickly and easily for the presence of ARGs is crucial in order to facilitate their monitoring in the environment. As current laboratory methods for the detection and surveillance of antimicrobial resistant bacteria in the environment were limited in their effectiveness and scope, the dissertation begins by describing the design and implementation of a Search Engine for Antimicrobial Resistance (SEAR), a pipeline and web interface for detection of horizontally-acquired ARGs in raw sequencing data. The suitability of metagenomic methods for monitoring the ARG content of effluents from faecal sources was then assessed via a pilot study of a river catchment. Novel metagenomes generated from effluents entering the catchment were interrogated for ARGs. The relative abundance of ARGs in effluents were determined to be higher relative to the background environment, as were sequences relating to human and animal pathogens and mobile genetic elements. Thus, effluents were implicated in the dissemination of ARGs throughout the aquatic environment. To determine if ARGs were potentially in use in the environment, the expression of ARGs within effluents was then evaluated across a series of longitudinal samples through the use of metatranscriptomics, and the presence of potential environmental antimicrobial selection pressures was examined. This demonstrated that the abundance of ARGs, as well as antimicrobial usage at the effluent source, was correlated with the transcription of ARGs in aquatic environments. The work described in this dissertation has also found that horizontally transmitted ARGs were present in pathogenic endospore-forming bacteria commonly found across the aquatic environment, potentially providing a mechanism for ARG persistence in the environment. Finally, these findings were integrated into a universal framework for monitoring ARG dissemination in aquatic environments and used to highlight the developments required to incorporate this framework into future environmental ARG research and to facilitate antimicrobial resistance risk assessments.
Subjects/Keywords: 579; Metagenomics; Antimicrobial resistance; Antibiotic resistance; Wastewater
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APA (6th Edition):
Rowe, W. (2016). Antimicrobial resistance gene monitoring in aquatic environments. (Doctoral Dissertation). University of Cambridge. Retrieved from https://www.repository.cam.ac.uk/handle/1810/253755 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683707
Chicago Manual of Style (16th Edition):
Rowe, Will. “Antimicrobial resistance gene monitoring in aquatic environments.” 2016. Doctoral Dissertation, University of Cambridge. Accessed February 27, 2020.
https://www.repository.cam.ac.uk/handle/1810/253755 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683707.
MLA Handbook (7th Edition):
Rowe, Will. “Antimicrobial resistance gene monitoring in aquatic environments.” 2016. Web. 27 Feb 2020.
Vancouver:
Rowe W. Antimicrobial resistance gene monitoring in aquatic environments. [Internet] [Doctoral dissertation]. University of Cambridge; 2016. [cited 2020 Feb 27].
Available from: https://www.repository.cam.ac.uk/handle/1810/253755 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683707.
Council of Science Editors:
Rowe W. Antimicrobial resistance gene monitoring in aquatic environments. [Doctoral Dissertation]. University of Cambridge; 2016. Available from: https://www.repository.cam.ac.uk/handle/1810/253755 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683707
University of Sydney
23.
Seebacher, Nicole Aveline.
Overcoming the Dual Mechanism of Stress-Induced, Pgp-Mediated Drug Resistance using Novel Thiosemicarbazones
.
Degree: 2015, University of Sydney
URL: http://hdl.handle.net/2123/13847
► Multi-drug resistance (MDR) is the principal mechanism by which many cancers develop resistance to chemotherapy drugs. It is the major factor responsible for the failure…
(more)
▼ Multi-drug resistance (MDR) is the principal mechanism by which many cancers develop resistance to chemotherapy drugs. It is the major factor responsible for the failure of many forms of chemotherapy. P-glycoprotein (Pgp) is the most highly studied ABC transporter involved in the efflux of cytotoxic substances out of the cell. Studies have shown that Pgp expression is up-regulated in tumour cells through the activation of the hypoxia-inducible factor-1 (HIF-1) pathway. Interestingly, this protein is typically up-regulated by conditions of oxidative stress, such as hypoxia and nutrient limitation, and has been measured at elevated levels within tumours. Consequently, the tumour micro-environment may play an important part in regulating MDR.
For the first time, the work reported in this thesis reveals underlying cellular pathways involving regulation of both surface and intracellular MDR by the tumour micro-environment. Moreover, the use of novel thiosemicarbazones to overcome MDR is demonstrated as a promising therapeutic strategy in combination with common chemotherapeutic agents that are subject to lysosomal trapping. These findings may help significantly improve the activity of existing chemotherapeutics and help improve patient treatment outcomes with potent thiosemicarbazones, such as Di-2-pyridylketone 4-cyclohexyl, 4-methyl-3-thiosemicarbazone (DpC), that will enter clinical trials in late 2015.
Subjects/Keywords: P-glycoprotein;
Multidrug resistance;
Resistance;
Chemotherapy
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APA ·
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APA (6th Edition):
Seebacher, N. A. (2015). Overcoming the Dual Mechanism of Stress-Induced, Pgp-Mediated Drug Resistance using Novel Thiosemicarbazones
. (Thesis). University of Sydney. Retrieved from http://hdl.handle.net/2123/13847
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):
Seebacher, Nicole Aveline. “Overcoming the Dual Mechanism of Stress-Induced, Pgp-Mediated Drug Resistance using Novel Thiosemicarbazones
.” 2015. Thesis, University of Sydney. Accessed February 27, 2020.
http://hdl.handle.net/2123/13847.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Seebacher, Nicole Aveline. “Overcoming the Dual Mechanism of Stress-Induced, Pgp-Mediated Drug Resistance using Novel Thiosemicarbazones
.” 2015. Web. 27 Feb 2020.
Vancouver:
Seebacher NA. Overcoming the Dual Mechanism of Stress-Induced, Pgp-Mediated Drug Resistance using Novel Thiosemicarbazones
. [Internet] [Thesis]. University of Sydney; 2015. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/2123/13847.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Seebacher NA. Overcoming the Dual Mechanism of Stress-Induced, Pgp-Mediated Drug Resistance using Novel Thiosemicarbazones
. [Thesis]. University of Sydney; 2015. Available from: http://hdl.handle.net/2123/13847
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
24.
Shawa, Misheck.
Risk factors and Alleles of extended spectrum Beta-Lactamase(ESBL) producing Escherichia coli at the University Teaching Hospital, Zambia.
Degree: 2015, University of Zimbabwe
URL: http://dspace.unza.zm/handle/123456789/4464
► The limitation of antibacterial treatment options imposed by the emergence of bacterial resistant organisms calls for the correct identification of the genes involved in mediating…
(more)
▼ The limitation of antibacterial treatment options imposed by the emergence of bacterial resistant organisms calls for the correct identification of the genes involved in mediating resistance. In this study, antimicrobial resistance was determined in terms of the presence of extended-spectrum beta-lactamases (ESBL) among Escherichia coli isolates obtained from patients admitted at the University Teaching Hospital (UTH) in Zambia. A total of 400 rectal swabs were obtained and subjected to initial screening using MacConkey agar supplemented with cefotaxime. blaTEM, blaSHV and bla CTX-M genes in ESBL producing E. coli were detected using Polymerase Chain Reaction (PCR). All CTX-M positive isolates were subjected to sensitivity patterns using 11 different antibiotics: ampicillin (AMP), trimethoprim-sulphamethoxazole (SXT), streptomycin (STR), tetracycline (TET), gentamycin (GEN), nalidixic acid (NAL), ceftazidime (CAZ), chloramphenicol (CHL), norfloxacin (NOR), ciprofloxacin (CIP) and cefotaxime (CTX).
The prevalence of ESBL producing E. coli was 19% (76/400). Among the ESBL producing E. coli, 25 out of 76 (32.9%) were positive for CTX-M genes. Of the 25 CTX-M positive isolates, 9 (36%) isolates were positive for SHV genes and 9 (36%) were positive for TEM genes. The highest resistance was found to be to nalidixic acid (96%), followed by sulfamethoxazole-trimethoprim, tetracycline and ceftazidime (92% each). The least resistance was to ampicillin (60%). Male gender (p=0.014, 95% CI=1.198-4.813) and history of surgery (p=0.01, 95% CI=1.196-3.740) were found to be significant risk factors for ESBL presence. The findings emphasize that ESBL-producing bacteria are present among patients at the UTH, and that these organisms exhibit co-resistance to several classes of antibiotics.
Subjects/Keywords: Drug resistance, Microbial; Drug resistance in microorganisms
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APA (6th Edition):
Shawa, M. (2015). Risk factors and Alleles of extended spectrum Beta-Lactamase(ESBL) producing Escherichia coli at the University Teaching Hospital, Zambia. (Thesis). University of Zimbabwe. Retrieved from http://dspace.unza.zm/handle/123456789/4464
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):
Shawa, Misheck. “Risk factors and Alleles of extended spectrum Beta-Lactamase(ESBL) producing Escherichia coli at the University Teaching Hospital, Zambia.” 2015. Thesis, University of Zimbabwe. Accessed February 27, 2020.
http://dspace.unza.zm/handle/123456789/4464.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Shawa, Misheck. “Risk factors and Alleles of extended spectrum Beta-Lactamase(ESBL) producing Escherichia coli at the University Teaching Hospital, Zambia.” 2015. Web. 27 Feb 2020.
Vancouver:
Shawa M. Risk factors and Alleles of extended spectrum Beta-Lactamase(ESBL) producing Escherichia coli at the University Teaching Hospital, Zambia. [Internet] [Thesis]. University of Zimbabwe; 2015. [cited 2020 Feb 27].
Available from: http://dspace.unza.zm/handle/123456789/4464.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Shawa M. Risk factors and Alleles of extended spectrum Beta-Lactamase(ESBL) producing Escherichia coli at the University Teaching Hospital, Zambia. [Thesis]. University of Zimbabwe; 2015. Available from: http://dspace.unza.zm/handle/123456789/4464
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Cambridge
25.
Rowe, Will.
Antimicrobial resistance gene monitoring in aquatic environments.
Degree: PhD, 2016, University of Cambridge
URL: https://www.repository.cam.ac.uk/handle/1810/253755https://www.repository.cam.ac.uk/bitstream/1810/253755/2/license.txt
;
https://www.repository.cam.ac.uk/bitstream/1810/253755/3/license_rdf
;
https://www.repository.cam.ac.uk/bitstream/1810/253755/4/DISSERTATION.corrected.pdf.txt
;
https://www.repository.cam.ac.uk/bitstream/1810/253755/5/DISSERTATION.corrected.pdf.jpg
► This dissertation documents the development of an environmental framework for monitoring antimicrobial resistance gene (ARG) dissemination in the aquatic environment. The work opens with a…
(more)
▼ This dissertation documents the development of an environmental framework for monitoring antimicrobial resistance gene (ARG) dissemination in the aquatic environment. The work opens with a review of the relevant literature and outlines the importance of an environmental framework for monitoring ARG dissemination as part of antimicrobial resistance risk assessments.
The ability to interrogate sequencing data quickly and easily for the presence of ARGs is crucial in order to facilitate their monitoring in the environment. As current laboratory methods for the detection and surveillance of antimicrobial resistant bacteria in the environment were limited in their effectiveness and scope, the dissertation begins by describing the design and implementation of a Search Engine for Antimicrobial Resistance (SEAR), a pipeline and web interface for detection of horizontally-acquired ARGs in raw sequencing data.
The suitability of metagenomic methods for monitoring the ARG content of effluents from faecal sources was then assessed via a pilot study of a river catchment. Novel metagenomes generated from effluents entering the catchment were interrogated for ARGs. The relative abundance of ARGs in effluents were determined to be higher relative to the background environment, as were sequences relating to human and animal pathogens and mobile genetic elements. Thus, effluents were implicated in the dissemination of ARGs throughout the aquatic environment.
To determine if ARGs were potentially in use in the environment, the expression of ARGs within effluents was then evaluated across a series of longitudinal samples through the use of metatranscriptomics, and the presence of potential environmental antimicrobial selection pressures was examined. This demonstrated that the abundance of ARGs, as well as antimicrobial usage at the effluent source, was correlated with the transcription of ARGs in aquatic environments.
The work described in this dissertation has also found that horizontally transmitted ARGs were present in pathogenic endospore-forming bacteria commonly found across the aquatic environment, potentially providing a mechanism for ARG persistence in the environment.
Finally, these findings were integrated into a universal framework for monitoring ARG dissemination in aquatic environments and used to highlight the developments required to incorporate this framework into future environmental ARG research and to facilitate antimicrobial resistance risk assessments.
Subjects/Keywords: Metagenomics; Antimicrobial resistance; Antibiotic resistance; Wastewater
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APA ·
Chicago ·
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Export
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APA (6th Edition):
Rowe, W. (2016). Antimicrobial resistance gene monitoring in aquatic environments. (Doctoral Dissertation). University of Cambridge. Retrieved from https://www.repository.cam.ac.uk/handle/1810/253755https://www.repository.cam.ac.uk/bitstream/1810/253755/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/253755/3/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/253755/4/DISSERTATION.corrected.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/253755/5/DISSERTATION.corrected.pdf.jpg
Chicago Manual of Style (16th Edition):
Rowe, Will. “Antimicrobial resistance gene monitoring in aquatic environments.” 2016. Doctoral Dissertation, University of Cambridge. Accessed February 27, 2020.
https://www.repository.cam.ac.uk/handle/1810/253755https://www.repository.cam.ac.uk/bitstream/1810/253755/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/253755/3/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/253755/4/DISSERTATION.corrected.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/253755/5/DISSERTATION.corrected.pdf.jpg.
MLA Handbook (7th Edition):
Rowe, Will. “Antimicrobial resistance gene monitoring in aquatic environments.” 2016. Web. 27 Feb 2020.
Vancouver:
Rowe W. Antimicrobial resistance gene monitoring in aquatic environments. [Internet] [Doctoral dissertation]. University of Cambridge; 2016. [cited 2020 Feb 27].
Available from: https://www.repository.cam.ac.uk/handle/1810/253755https://www.repository.cam.ac.uk/bitstream/1810/253755/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/253755/3/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/253755/4/DISSERTATION.corrected.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/253755/5/DISSERTATION.corrected.pdf.jpg.
Council of Science Editors:
Rowe W. Antimicrobial resistance gene monitoring in aquatic environments. [Doctoral Dissertation]. University of Cambridge; 2016. Available from: https://www.repository.cam.ac.uk/handle/1810/253755https://www.repository.cam.ac.uk/bitstream/1810/253755/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/253755/3/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/253755/4/DISSERTATION.corrected.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/253755/5/DISSERTATION.corrected.pdf.jpg
Cornell University
26.
Villani, Sara.
The Prevalence And Molecular Mechanisms Of Single-Site Fungicide Resistance In The Apple Scab Pathogen, Venturia Inaequalis
.
Degree: 2016, Cornell University
URL: http://hdl.handle.net/1813/43713
► Apple scab, caused by the fungal pathogen Venturia inaequalis is among the most prevalent and economically important diseases in commercial apple orchards in regions with…
(more)
▼ Apple scab, caused by the fungal pathogen Venturia inaequalis is among the most prevalent and economically important diseases in commercial apple orchards in regions with temperate climates worldwide. The absence of durable apple scab
resistance in the majority of commercially desired cultivars often mandates numerous fungicide applications each season to successfully manage the disease. Highly effective single-site fungicides have enhanced the ability to manage a number of phytopathogenic fungi, including V. inaequalis. Unfortunately the highly specific nature and repetitive use of these fungicides has led to their diminished efficacy and widespread
resistance in V. inaequalis. The identification of the prevalence of single-site
resistance in populations of V. inaequalis and an understanding of molecular mechanisms of
resistance to these fungicides can aid in the rapid detection of fungicide
resistance, the deployment of fungicide anti-
resistance management strategies, and the development of efficient and effective chemical management programs for apple scab control. In this dissertation, a combination of applied and basic research was implemented to gain further understanding of the molecular mechanisms associated with practical
resistance to DMI and QoI fungicides in isolates and/or populations of V. inaequalis. Microscopy-aided mycelial growth assays were used to determine sensitivity phenotypes to the DMI fungicides myclobutanil and difenoconazole and to the QoI fungicide trifloxystrobin. The majority of populations of V. inaequalis collected throughout the Northeastern, Mid-Atlantic, and Mid-Western United States were found to have reduced sensitivity or practical
resistance to myclobutanil, but not difenoconazole. Illumina sequencing and reverse-transcriptase quantitative PCR were used to identify the contribution of target gene overexpression and the presence of upstream repeated elements in myclobutanil and difenoconazole
resistance. Another molecular technique, allelespecific quantitative PCR was used to evaluate the role of target gene heteroplasmy in the quantitative
resistance response and practical
resistance to trifloxystrobin in isolates and populations of V. inaequalis. Additionally, baseline sensitivity of V. inaequalis to three SDHI fungicides was determined, and the sdhB gene, a target for SDHI fungicides, was identified and characterized. In summary, the results of this dissertation contribute to the identification and understanding of mechanisms associated with single-site fungicide
resistance in V. inaequalis.
Advisors/Committee Members: Burr,Thomas J (committeeMember), Cheng,Lailiang (committeeMember), Rosenberger,David A (committeeMember).
Subjects/Keywords: apple scab;
fungicide resistance;
practical resistance
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APA ·
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Manager
APA (6th Edition):
Villani, S. (2016). The Prevalence And Molecular Mechanisms Of Single-Site Fungicide Resistance In The Apple Scab Pathogen, Venturia Inaequalis
. (Thesis). Cornell University. Retrieved from http://hdl.handle.net/1813/43713
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):
Villani, Sara. “The Prevalence And Molecular Mechanisms Of Single-Site Fungicide Resistance In The Apple Scab Pathogen, Venturia Inaequalis
.” 2016. Thesis, Cornell University. Accessed February 27, 2020.
http://hdl.handle.net/1813/43713.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Villani, Sara. “The Prevalence And Molecular Mechanisms Of Single-Site Fungicide Resistance In The Apple Scab Pathogen, Venturia Inaequalis
.” 2016. Web. 27 Feb 2020.
Vancouver:
Villani S. The Prevalence And Molecular Mechanisms Of Single-Site Fungicide Resistance In The Apple Scab Pathogen, Venturia Inaequalis
. [Internet] [Thesis]. Cornell University; 2016. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/1813/43713.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Villani S. The Prevalence And Molecular Mechanisms Of Single-Site Fungicide Resistance In The Apple Scab Pathogen, Venturia Inaequalis
. [Thesis]. Cornell University; 2016. Available from: http://hdl.handle.net/1813/43713
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Mississippi State University
27.
Givens, Wade Alexander.
SHIFTS IN HERBICIDE USE, TILLAGE PRACTICES, AND PERCEPTIONS OF GLYPHOSATE-RESISTANT WEEDS FOLLOWING ADOPTION OF GLYPHOSATE-RESISTANT CROPS.
Degree: PhD, Plant and Soil Sciences, 2010, Mississippi State University
URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-03312010-103616/
;
► A survey was conducted by phone to nearly 1,200 growers in six states (Illinois, Indiana, Iowa, Mississippi, Nebraska, and North Carolina) in 2005. The…
(more)
▼ A survey was conducted by phone to nearly 1,200 growers in six states (Illinois,
Indiana, Iowa, Mississippi, Nebraska, and North Carolina) in 2005. The survey measured
producers cropping history, perception of glyphosate-resistant (GR) weeds, past and
present weed pressure, tillage practices, and herbicide use as affected by the adoption
of GR crops. The objectives of this study were to determine the effect of GR crop use
on producers tillage practices; changes in herbicide use patterns after adoption of a GR
crop; effect of grower awareness of GR weeds on sources of information growers use;
and growers perceptions on
resistance management based on knowledge of GR weeds
in their farming operation.
The adoption of GR cropping systems contributed to large increases in the
percentage of growers using no-till and reduced-till systems. Tillage intensity declined
more in continuous GR cotton and GR soybean (45 and 23%, respectively) than in
rotations that included GR corn or non-GR crops. Tillage intensity declined more in the
states of Mississippi and North Carolina than in the other states, with 33% of the growers
in these states shifting to more conservative tillage practices after the adoption of a GR
crop. This was in part due to the lower amount of conservation tillage adoption in these
states prior to GR crop availability.
With respect to herbicide use patterns, frequently used herbicides for fall
applications were 2,4-D and glyphosate; these herbicides were often used for preplant,
burndown weed control in the spring. As expected, crop rotations using GR crops had a
high percentage of respondents that made one to three POST applications of glyphosate
per year. Overall, glyphosate use has continued to increase, with concomitant
decreases in utilization of other herbicides.
Concerning grower awareness of GR weeds and perceptions of
resistance
management in 2005, the majority of the growers (88%) were aware of a weeds
potential to develop
resistance to glyphosate, while 44% were aware of state-specific,
documented cases of glyphosate weed
resistance. Growers that have had experience
with GR weeds were more knowledgeable about
resistance management practices that
could be used to mitigate them.
Advisors/Committee Members: David R. Shaw (chair), Clifford H. Koger (committee member), John D. Madsen (committee member), John D. Byrd (committee member), Michael E. Newman (committee member).
Subjects/Keywords: grower survey. resistance management; glyphosate-resistance
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APA ·
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Export
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Manager
APA (6th Edition):
Givens, W. A. (2010). SHIFTS IN HERBICIDE USE, TILLAGE PRACTICES, AND PERCEPTIONS OF GLYPHOSATE-RESISTANT WEEDS FOLLOWING ADOPTION OF GLYPHOSATE-RESISTANT CROPS. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-03312010-103616/ ;
Chicago Manual of Style (16th Edition):
Givens, Wade Alexander. “SHIFTS IN HERBICIDE USE, TILLAGE PRACTICES, AND PERCEPTIONS OF GLYPHOSATE-RESISTANT WEEDS FOLLOWING ADOPTION OF GLYPHOSATE-RESISTANT CROPS.” 2010. Doctoral Dissertation, Mississippi State University. Accessed February 27, 2020.
http://sun.library.msstate.edu/ETD-db/theses/available/etd-03312010-103616/ ;.
MLA Handbook (7th Edition):
Givens, Wade Alexander. “SHIFTS IN HERBICIDE USE, TILLAGE PRACTICES, AND PERCEPTIONS OF GLYPHOSATE-RESISTANT WEEDS FOLLOWING ADOPTION OF GLYPHOSATE-RESISTANT CROPS.” 2010. Web. 27 Feb 2020.
Vancouver:
Givens WA. SHIFTS IN HERBICIDE USE, TILLAGE PRACTICES, AND PERCEPTIONS OF GLYPHOSATE-RESISTANT WEEDS FOLLOWING ADOPTION OF GLYPHOSATE-RESISTANT CROPS. [Internet] [Doctoral dissertation]. Mississippi State University; 2010. [cited 2020 Feb 27].
Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-03312010-103616/ ;.
Council of Science Editors:
Givens WA. SHIFTS IN HERBICIDE USE, TILLAGE PRACTICES, AND PERCEPTIONS OF GLYPHOSATE-RESISTANT WEEDS FOLLOWING ADOPTION OF GLYPHOSATE-RESISTANT CROPS. [Doctoral Dissertation]. Mississippi State University; 2010. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-03312010-103616/ ;
Mississippi State University
28.
Weirich, Jason Wade.
ASSESSING LONG-TERM VIABILITY OF GLYPHOSATE-RESISTANT TECHNOLOGY AS A FOUNDATION FOR CROPPING SYSTEMS.
Degree: PhD, Plant and Soil Sciences, 2010, Mississippi State University
URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06182010-150430/
;
► The introduction of glyphosate-resistant (GR) crops in the late 1990s changed the way producers used herbicides to control weeds. Since the introduction of GR…
(more)
▼ The introduction of glyphosate-resistant (GR) crops in the late 1990s changed the
way producers used herbicides to control weeds. Since the introduction of GR crops
producers have relied on glyphosate alone for weed control instead of utilizing multiple
modes of action for weed control. This over-reliance resulted in several weed species
developing
resistance to glyphosate. This has resulted in organizations from the public
and private sector questioning the sustainability of GR cropping systems.
Researchers from Illinois, Indiana, Iowa, Mississippi, Nebraska, and North
Carolina established 156 on-farm trials to determine the sustainability of GR cropping
systems. The objectives of this study were: to determine the economics of a university
weed
resistance best management practice (BMP) versus a producers normal production
practice; to evaluate when a producer that is risk neutral (profit maximizing) or risk
averse should adopt a weed
resistance BMP; and to compare the influences of using a
university weed
resistance BMP to a producers normal production practice on the 27
most common weed species in Mississippi. In all instances, the university weed
resistance BMP utilized multiple modes of action in conjunction with glyphosate.
A university weed
resistance BMP can provide the same level of control on 27 of
the most common weeds in Mississippi that a producer has become accustomed to with a
glyphosate alone system, while delaying or controlling GR weeds. A university weed
resistance BMP resulted in an increase in weed control cost, but similar yields and
economic returns when compared to a producers normal production practice. Rotating a
GR crop with a different GR crop resulted in higher economic returns when compared to
a continuous GR cropping system or a GR crop followed by a non-GR crop rotation.
Producers are often reluctant to adopt a weed
resistance BMP because of the perceived
increased cost for weed control. A risk neutral or risk averse producer should adopt a
weed
resistance BMP and feel confident that their decision will provide weed control
equivalent to a glyphosate alone weed control program before
resistance developed, delay
or control GR weeds and be economically sound.
Advisors/Committee Members: David R. Shaw (chair), Gregory Ibendahl (committee member), John D. Byrd Jr. (committee member), Daniel B. Reynolds (committee member), Gary N. Ervin (committee member).
Subjects/Keywords: best management practice; resistance; glyphosate resistance
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Weirich, J. W. (2010). ASSESSING LONG-TERM VIABILITY OF GLYPHOSATE-RESISTANT TECHNOLOGY AS A FOUNDATION FOR CROPPING SYSTEMS. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-06182010-150430/ ;
Chicago Manual of Style (16th Edition):
Weirich, Jason Wade. “ASSESSING LONG-TERM VIABILITY OF GLYPHOSATE-RESISTANT TECHNOLOGY AS A FOUNDATION FOR CROPPING SYSTEMS.” 2010. Doctoral Dissertation, Mississippi State University. Accessed February 27, 2020.
http://sun.library.msstate.edu/ETD-db/theses/available/etd-06182010-150430/ ;.
MLA Handbook (7th Edition):
Weirich, Jason Wade. “ASSESSING LONG-TERM VIABILITY OF GLYPHOSATE-RESISTANT TECHNOLOGY AS A FOUNDATION FOR CROPPING SYSTEMS.” 2010. Web. 27 Feb 2020.
Vancouver:
Weirich JW. ASSESSING LONG-TERM VIABILITY OF GLYPHOSATE-RESISTANT TECHNOLOGY AS A FOUNDATION FOR CROPPING SYSTEMS. [Internet] [Doctoral dissertation]. Mississippi State University; 2010. [cited 2020 Feb 27].
Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06182010-150430/ ;.
Council of Science Editors:
Weirich JW. ASSESSING LONG-TERM VIABILITY OF GLYPHOSATE-RESISTANT TECHNOLOGY AS A FOUNDATION FOR CROPPING SYSTEMS. [Doctoral Dissertation]. Mississippi State University; 2010. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06182010-150430/ ;
29.
Elahi, Mohammad Tariq.
Towards more Effective Censorship Resistance Systems.
Degree: 2015, University of Waterloo
URL: http://hdl.handle.net/10012/9744
► Internet censorship resistance systems (CRSs) have so far been designed in an ad-hoc manner. The fundamentals are unclear and the foundations are shaky. Censors are,…
(more)
▼ Internet censorship resistance systems (CRSs) have so far been designed in an ad-hoc manner. The fundamentals are unclear and the foundations are shaky. Censors are, more and more, able to take advantage of this situation. Future censorship resistance systems ought to be built from strong theoretical underpinnings and be based on empirical evidence.
Our approach is based on systematizing the CRS field and its players. Informed by this systematization we develop frameworks that have broad scope, from which we gain general insight as well as answers to specific questions. We develop theoretical and simulation-based analysis tools 1) for learning how to manipulate censor behavior using game-theoretic tactics, 2) for learning about CRS-client activity levels on CRS networks, and finally 3) for evaluating security parameters in CRS designs.
We learn that there are gaps in the CRS designer's arsenal: certain censor attacks go unmitigated and the dynamics of the censorship arms race are not modeled. Our game-theoretic analysis highlights how managing the base rate of CRS traffic can cause stable equilibriums where the censor allows some amount of CRS communication to occur. We design and deploy a privacy-preserving data gathering tool, and use it to collect statistics to help answer questions about the prevalence of CRS-related traffic in actual CRS communication networks. Finally, our security evaluation of a popular CRS exposes suboptimal settings, which have since been optimized according to our recommendations.
All of these contributions help support the thesis that more formal and empirically driven CRS designs can have better outcomes than the current state of the art.
Subjects/Keywords: Censorship Resistance; Censorship Resistance Systems; Circumvention
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Elahi, M. T. (2015). Towards more Effective Censorship Resistance Systems. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/9744
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):
Elahi, Mohammad Tariq. “Towards more Effective Censorship Resistance Systems.” 2015. Thesis, University of Waterloo. Accessed February 27, 2020.
http://hdl.handle.net/10012/9744.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Elahi, Mohammad Tariq. “Towards more Effective Censorship Resistance Systems.” 2015. Web. 27 Feb 2020.
Vancouver:
Elahi MT. Towards more Effective Censorship Resistance Systems. [Internet] [Thesis]. University of Waterloo; 2015. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/10012/9744.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Elahi MT. Towards more Effective Censorship Resistance Systems. [Thesis]. University of Waterloo; 2015. Available from: http://hdl.handle.net/10012/9744
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Colorado State University
30.
Rovira Sanz, Pablo.
Impact of antibiotic use on resistance in beef feedlot and dairy cattle.
Degree: PhD, Animal Sciences, 2017, Colorado State University
URL: http://hdl.handle.net/10217/183928
► In recent years, consumer demand for natural and organic foods has increased, partly due to concerns about the use of antimicrobials in food producing animals.…
(more)
▼ In recent years, consumer demand for natural and organic foods has increased, partly due to concerns about the use of antimicrobials in food producing animals. The aim of this study was to evaluate antimicrobial
resistance (AMR) in beef feedlot and dairy cattle raised without use of antibiotics compared to cattle raised in conventional (CONV) production. Three research projects were conducted to accomplish that general goal. In the first study, a conventional feedlot, natural feedlot, conventional dairy and organic dairy were visited to collect cattle feces, wastewater from lagoons and soil where the wastewater was applied. After DNA extraction, sequencing, and processing, metagenomic reads were aligned to reference databases for identification of antibiotic
resistance genes (ARGs; i.e. the resistome) and bacteria (microbiome). Resistome composition was influenced by rearing method, cattle type, and type of sample. Most mechanisms of
resistance affected by rearing method were enriched (P < 0.05) in conventional samples. Resistome differences were greatest for wastewater samples by rearing method but with contradictory results that suggested an impact of effluent management on wastewater resistome.
Resistance to tetracycline and macrolide-lincosamide-streptogramin classes were more abundant in feces of feedlot cattle than in dairy cattle (P < 0.05); whereas
resistance to beta-lactams was greatest in feces of dairy cattle (P < 0.05). Resistome and microbiome of feces differed (P < 0.05) between wastewater and soil samples. Results indicated that ARGs are widespread in beef feedlot and dairy cattle farms even in those with restricted antibiotic use. In the second study, feces from RWA (n=36) and CONV (n=36) cattle lots were recovered from colons at a commercial beef processing plant. Samples were equally distributed by month and production protocol over one year (3 samples/production protocol/month). After extracting DNA from individual samples, composite samples were prepared by mixing DNA from each lot into a single composite sample (N = 72) and sequencing the composites on an Illumina platform. Metagenomic reads were processed similarly to those in experiment 1for identification of ARGs and bacteria. Resistomes of CONV and RWA cattle were significantly different by season. In general, mechanisms conferring
resistance to beta-lactams, tetracyclines, multi-drug and macrolides were more prevalent (P < 0.05) in feces from CONV colons than in RWA colons. In the third study, a systematic review and meta-analysis was performed to assess the relationship between antimicrobial use (AMU) and antimicrobial
resistance (AMR) in feedlot cattle. After conducting a literature search and screening reported studies, 32 studies were selected for use that addressed AMR in Escherichia coli, Enterococcus, Salmonella, Campylobacter, and Mannheimia haemolytica. Overall, 60% (95% CI: 26% to 88%) of the observational studies and 50% (95% CI: 30% to 70%) of the controlled trials reported a positive association between AMU and AMR.…
Advisors/Committee Members: Belk, Keith (advisor), Morley, Paul (committee member), Schmidt, John (committee member), Yang, Hua (committee member).
Subjects/Keywords: bacteria; metagenomics; antimicrobial resistance; resistance genes; cattle
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APA (6th Edition):
Rovira Sanz, P. (2017). Impact of antibiotic use on resistance in beef feedlot and dairy cattle. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/183928
Chicago Manual of Style (16th Edition):
Rovira Sanz, Pablo. “Impact of antibiotic use on resistance in beef feedlot and dairy cattle.” 2017. Doctoral Dissertation, Colorado State University. Accessed February 27, 2020.
http://hdl.handle.net/10217/183928.
MLA Handbook (7th Edition):
Rovira Sanz, Pablo. “Impact of antibiotic use on resistance in beef feedlot and dairy cattle.” 2017. Web. 27 Feb 2020.
Vancouver:
Rovira Sanz P. Impact of antibiotic use on resistance in beef feedlot and dairy cattle. [Internet] [Doctoral dissertation]. Colorado State University; 2017. [cited 2020 Feb 27].
Available from: http://hdl.handle.net/10217/183928.
Council of Science Editors:
Rovira Sanz P. Impact of antibiotic use on resistance in beef feedlot and dairy cattle. [Doctoral Dissertation]. Colorado State University; 2017. Available from: http://hdl.handle.net/10217/183928
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