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Synthesis on some new-l-lactam antibiotics : a thesisUgolini, Antonio. January 1981 (has links)
The syntheses of the cephalosporin analogs cis-N-(2'-hydroxyphenyl)-3-phenylacetamido-4-hydroxymethyl-2-azetidinone (37), cis-N-(2'-hydroxy-5'-nitrophenyl)-3-phenylacetamido-4-hydroxymethyl-2-azetidinone (59) and 7-(beta)-phenylacetamido-3'-hydroxybenzo{3,4}-0,2-isocephem (77) are described. Compounds 37 and 59 were devoid of antibacterial activity, while (beta)-lactam 77 showed weak activity against two micoorganisms. / Two new ring systems, 2-phenylcarbapenams 146 and 157 have been prepared. These are key intermediates in the syntheses of phosphonic acid carbapenam 148 and the carboxylic acid derivative 158, respectively. / The one carbon homologation of (beta)-trimethylsilyl-(alpha),(beta)-unsaturated esters with diazomethane was extended to the corresponding (beta)-trimethylsilyl or (beta)-t-butyldimethylsilyl aldehydes.
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Precise determination of the 136Xe – 136Ba atomic mass difference and related mass differences in Ba and CdMcCowan, Peter 13 January 2010 (has links)
In light of present (EXO) and future (BOREXINO & XMASS) projects searching for evidence of the, as yet, unobserved double-beta decay of 136Xe, an atomic mass difference of 136Xe – 136Ba was determined using the high-precision Manitoba II mass spectrometer at the University of Manitoba. The Q-value for this difference was determined to be 2458.72(56) keV.
The double-beta decay mode can be either neutrino (ββ2υ) or neutrinoless (ββ0υ), where the latter would be proof of the Majorana nature of neutrinos. A ββ0υ decay, which violates several principles of the Standard Model of particle physics, would emit only electrons and would provide a defined peak at the Q-value for the decay. This decay would also require the Majorana neutrino to have a non-zero rest mass and be its own antiparticle.
Results of mass measurements on mass doublets of 135Ba, 136Ba, 137Ba, and 138Ba will be given. An improved measurement of the 116Cd35Cl - 114Cd37Cl doublet, previously done by Meredith et al. in 1973, will also be given.
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A beta spectrometer using a GE (HP) detector in a high magnetic field /Al-Alousi, Ali Khalil January 1984 (has links)
No description available.
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The effect of beta-alanine supplementation on aerobic and anaerobic capacity in trained cyclistsLindsay, Angus January 2011 (has links)
Beta-alanine supplementation has been shown to increase skeletal muscle carnosine concentration resulting in the delay of neuromuscular fatigue and an increased aerobic and anaerobic capacity. The current study investigated the effects of beta-alanine supplementation on aerobic and anaerobic capacity in trained cyclists. Fourteen highly-competitive (sprint, endurance, road and track) cyclists underwent an 8 week 6.4g/day protocol (beta-alanine and maltodextrin). Pre and post supplementation testing included a VO₂max test (familiarization and characterization), maximum aerobic power test (aerobic capacity), and 30s wingate anaerobic test (anaerobic capacity). Aerobic capacity parameter measures included aerobic and anaerobic thresholds, and maximum aerobic power, while anaerobic capacity parameters included fatigue index, average power, peak power, watts per kilogram, and final lactate concentration.
There was a lack of change in aerobic and anaerobic capacity parameters post supplementation for both groups. Assuming an increase in skeletal muscle carnosine concentration, results suggest 8 weeks 6.4g/day beta-alanine does not increase aerobic and anaerobic capacity in trained cyclists. This lack of change has 3 potential explanations; carnosines’ physicochemical H⁺ buffering ability was not substantially elevated to prevent muscular fatigue via acidosis, pH decrease is only one limiting factor in aerobic and anaerobic capacity, or other factors (neuromuscular junction failure, contractile failure, substrate depletion, metabolite accumulation, oxidative stress) influence muscular fatigue.
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Measurement of the neutral current in the standard model using the Tau Polarization asymmetries determined from the decay [formula]Rosvick, Myron R. 16 July 2015 (has links)
Graduate
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Ethiopian Jewish immigrants in Israel : living well and 'becoming deaf' in the homelandSchwarz, Tanya January 1998 (has links)
This thesis is an ethnographic study of the Ethiopian Jews, or Beta Israel, a few years after their migration from rural Ethiopian to urban Israel. For the Beta Israel, the most significant issue is not, as is commonly assumed, adaptation to modern society, which to a large extent they have successfully achieved. But rather, their primary concerns revolve around the notion of "belonging" in their new homeland, and the loss of control they are experiencing over their lives and those of their children. The thesis analyses the experience of immigration from the Beta Israel's own perspective and focuses on: first, the factors which contribute to the Beta Israel's sense of well-being in Israel, second, the problems and difficulties they experience, and finally, the strategies they are developing to overcome these difficulties. This study elucidates the meanings of two apparently contradictory ascriptions which the Ethiopian Jewish immigrants make about themselves: "being well" and "becoming deaf'. Their sense of well-being is a result of their successful recreation of communal life, their expression of ethnic pride, and their appreciation of their new country. The expression "becoming deaf', which also means in Amharic "becoming ignorant", denotes the older generation's frustration at their inability to understand Hebrew, their feeling of being excluded by dominant society, and the loss of control they experience over most aspects of their lives. For the younger generation, the sense of exclusion revolves around issues of racial discrimination. Ethiopian Jewish immigrants resist those aspects of dominant society which they dislike: they reject normative Jewish practices and uphold Beta Israel religious and cultural ones, ideologically counteract disparaging Israeli attitudes, develop strong ethnic bonds and engage in overt forms of resistance. The difficulties of the present are also overcome by creating a perfect past and an ideal future: in what I have called 'the homeland postponed', all Jews will be united in a colour-blind world of material plenty and purity.
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Inter- and intramolecular addition reactions of α-aminomethylcarbanions with carbonyl groupsLang-Anderson, Maria Mercedes Susana January 1995 (has links)
No description available.
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Effect of Gemini Surfactants on Amyloid Beta AggregationBahmani, Mehrnoosh January 2013 (has links)
Alzheimer’s disease (AD) is a progressive dementia affecting cognition, behavior, and functional status and there is no cure which exists for it. In AD, Amyloid Beta (Aβ) peptides form aggregates that are neurotoxic in the brain. Hence, molecules that are able to prevent Aß aggregation could be effective in AD treatment. Gemini surfactant (GS) molecules consist of two hydrophilic heads separated by a covalently bound spacer and two hydrophobic tails. Their structure gives rise to a number of unique properties, including low critical micelle concentrations, the ability to form multiple types of aggregates (governed primarily by the nature of the spacer group) and enhanced ability to bind to polymers. These properties make gemini surfactant a good choice for solubilizing very hydrophobic materials such as Aß. The aim of this study was to examine various GS structures to help us to understand their interaction with Aβ and the influence of spacer group in Aβ disassembly.
We employed 12-carbon tail GS with varying spacer groups of different hydrophilicities, such as: (-CH2-CH2-O)m, (-CH2)m, N(CH2)m, OH(CH2)4 and (OH)2(CH2)4. Surface tension measurement, isothermal titration calorimetry (ITC) and dynamic light scattering (DLS) have been employed to observe the gemini-Aβ interaction.
Surface tension measurements did not show a typical surfactant-polymer interaction; rather, the presence of Aß induced aggregate formation at concentrations well below the cmc. Headgroup areas were observed to decrease for some of the surfactants in the presence of Aß, which may result from partial neutralization of the surfactant headgroups and a relaxation of electrostatic repulsion resulting in decreased head group areas. ITC results suggest substantial reorganization of Aß/gemini surfactant aggregates, with distinct difference seen depending upon the nature of the headgroup. It was observed that in 12-(CH2)n-12 (n=2,3,4,7) shorter spacer gemini surfactants have stronger interaction with Aß than the ones with longer spacers. In the 12-4(OH)n-12 series, a stronger interaction was observed in the GS with 2 hydroxyl groups compared to one hydroxyl group GS. For 12-(EO)n-12 GS, a stronger interaction was observed in that GS with two ethoxy groups. In the 12-XN-12 series, although the 8N spacer is more hydrophilic than 5N, the interaction of 12-5N-12 with Aß was stronger than that of 12-8N-12. The particle size data also revealed that there is an interaction between gemini surfactant and Aß. It appeared that mixed micelles formed when the surfactant concentration increased in the Aß solution. Overall, it was observed that changes in the length and hydrophilic character of the gemini surfactant spacer influenced the type of interaction and gemini-Aβ conformation.
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Precise determination of the 136Xe – 136Ba atomic mass difference and related mass differences in Ba and CdMcCowan, Peter 13 January 2010 (has links)
In light of present (EXO) and future (BOREXINO & XMASS) projects searching for evidence of the, as yet, unobserved double-beta decay of 136Xe, an atomic mass difference of 136Xe – 136Ba was determined using the high-precision Manitoba II mass spectrometer at the University of Manitoba. The Q-value for this difference was determined to be 2458.72(56) keV.
The double-beta decay mode can be either neutrino (ββ2υ) or neutrinoless (ββ0υ), where the latter would be proof of the Majorana nature of neutrinos. A ββ0υ decay, which violates several principles of the Standard Model of particle physics, would emit only electrons and would provide a defined peak at the Q-value for the decay. This decay would also require the Majorana neutrino to have a non-zero rest mass and be its own antiparticle.
Results of mass measurements on mass doublets of 135Ba, 136Ba, 137Ba, and 138Ba will be given. An improved measurement of the 116Cd35Cl - 114Cd37Cl doublet, previously done by Meredith et al. in 1973, will also be given.
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Characterisation of the MAL2 proteins and their interaction with TPD52Robertson, Lindsay January 2006 (has links)
The human MAL2 protein has been demonstrated to regulate secretion in kidney epithelial cells in a lipid raft-dependent manner. Further, MAL2 interacts with TPD52, a protein that promotes secretion in rat pancreatic acinar cells. Two MAL2 homologues have recently been identified within rat pancreatic β-cells: MAL2A and MAL2B. This suggested that MAL2 and TPD52 might interact with each other to coordinate secretion within both human kidney epithelial cells and rat pancreatic β-cells. I report here that both <i>MAL2A </i>and <i>MAL2B </i>are expressed within rat pancreatic β-cells. Further, the expression of <i>MAL2B </i>appears to be tightly regulated as sequences within the 5’ UTR of the <i>MAL2B </i>transcript inhibit its translation. Both MAL2A and MAL2B are associated with lipid rafts. Attempts were made to identify interactions between TPD52 and the MAL2 proteins. GST pull-down assays indicated that TPD52 interacts with both MAL2A and MAL2B. This is consistent with previous observations and suggests that TPD52 does not interact with MAL2A or MAL2B via their N-termini, which are distinct between each MAL2 protein. However, a novel <i>Xenopus </i>egg extract interaction assay failed to detect an interaction between TPD52 and the MAL2 proteins. Further, immunohistochemistry indicated that TPD52 did not co-localise and either MAL2A or MAL2B within pancreatic β-cells. These findings indicate that TPD52 and the MAL2 proteins might participate in overlapping secretion pathways. Further, these data suggest that any interaction between TPD52 and the MAL2 proteins might be weak or transient. Finally, initial attempts were made to reduce <i>TPD52 </i>expression within β-cells via RNA silencing in order to elucidate the role of TPD52 in directing secretion. RNA silencing will also be used to examine the role of MAL2A in coordinating secretion.
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