Yes

<p> P. Gabriel constructed rings of quotients by inverting elements of multiplicative sets which satisfy the Ore and the reversibility conditions. We employ this technique in our study of localizations of non-noetherian rings at Goldie semiprime ideals. The three types of clans developed in this thesis enable us to decompose in a unique fashion (weakly) classical sets of prime ideals into (weak) clans which, in essence, are minimal localizable sets of prime ideals, satisfying certain properties. We further show that these (weak) clans are mutually disjoint sets. The different types of rings, brought into consideration, exhibit many interesting properties in the context of our localization theory.</p> <p> We characterize the AR-property for the Jacobson radical of a semilocal ring by considering finitely generated modules. In the study of rings which are module-finite over their centres, we describe expressly the injective hull of the semilocal ring modulo its Jacobson radical. These two facts enable us to establish an interrelationship between the (strongly) classical semiprime ideals of the ring and those of its central subring. Furthermore, we show that under certain conditions the Q-sets are precisely all the minimal localizable sets of prime ideals of the ring. In the case of group rings, the flatness condition can be lifted without jeopardizing the validity of the assertion.</p> <p> Lastly, we apply localization technique to characterize the group theoretic notion of q-nilpotency.</p> / Thesis / Doctor of Philosophy (PhD)

Master of Science / Department of Statistics / James W. Neill

<p>Examining the genetic basis across repeated origins of the same phenotypic adaptation allows us to address several questions pertaining to the genetic basis of adaptation. First, whether the genes and types of mutations that are involved in adaptation are predictable. Second, whether the underlying genetic changes can constrain future evolutionary trajectories. Here, I have focused on the genetics of blue to red flower color shifts, an adaptive shift that has repeatedly occurred across angiosperms. First, I review the literature and determine the relative contribution of functional vs. regulatory mutations to the evolution of red flowers can be predicted both on the mutational target size of each type of mutation and the degree of their associated deleterious pleiotropy. Chapter 2 characterizes the genetic basis of red flowers in Penstemon barbatus using a combination of gene expression and protein function assays. I demonstrated that multiple inactivating mutations to one anthocyanin pathway enzyme, F3'5'h, have occurred, but no mutations to any other component of the anthocyanin pathway have contributed to the evolution of red flowers. This suggests that F3'5'h may be a particularly favorable target for selection and also that evolutionary reversal to blue flowers would be highly unlikely. Chapter 3 investigates the genetic basis of an additional 12 origins of red flowers within Penstemon. Again, using a combination of gene expression and enzyme function assays, I found the genetic basis of these additional origins red flowers in Penstemon is highly predictable, involving redundant inactivating mutations to F3'5'h, and tissue-specific regulatory mutations to a second gene F3'h. Thus, the genetics of red flowers in Penstemon often involves inactivation of a non-pleiotropic gene, F3'5'h, but tissue-specific regulatory mutations to the pleiotropic gene F3'h. Furthermore, the presence of redundant inactivating mutations in many red-flowered Penstemon species indicates that the evolutionary reversal to blue flowers would be unlikely.</p> / Dissertation

Faculty of Science School of Chemistry 0204045a tspmkwi@hotmail.com / New possibilities in collection of polarographic and potentiometric experimental data in studies of metal–ligand systems by automated instrumental methods, and subsequent treatment of the polarographic data, whereby the degree of reversibility of the electrode processes varies, have been investigated in this work. An automated instrumental set–up was developed for applications in studies of metal–ligand solution equilibria by potentiometry and sampled Direct Current Polarography (DCP). The new set–up was designed based on virtual instrumentation principles whereby several commercially– available hardware units as well as custom–built electronic components, were interfaced to a personal computer that was equipped with appropriate hardware and control programs. The instrumental set–up was tested and validated by studying the protonation equilibria of the ligand glycine by Glass Electrode Potentiometry (GEP) as well as the complexation of the ligand glycine with Cd2+ by GEP and DCP. The new set–up provides increased versatility, accuracy and convenience in obtaining large numbers of experimental points in solution equilibria studies by DCP and GEP as opposed to the use of tedious and time–consuming manual methods. Nonlinear curve–fitting procedures, based on closed–form models that were derived here from suitable theoretical equations identified from literature, have been investigated in this work for applications in analysis of DC curves recorded on metal–ligand systems with variation in electrochemical reversibility. The applicability and limitations of the curve–fitting procedures developed have been tested in analysis of the DCP data collected on several metal–ligand systems involving Cd2+, Pb2+, Zn2+ and the ligands glycine and sarcosine, whereby the DCP studies of these systems exhibited reversible, quasi–reversible or irreversible electrochemical processes. Information on applicability and limitations of the proposed methods investigated in this work was derived by comparison of the results obtained from DCP, using the proposed methods, with either reported literature data and/or results obtained in this work by the independent analytical technique of GEP, which was deployed wherever it was found to be applicable to study the metal–ligand systems considered.

ABSTRACT Phenotypic flexibility in basal metabolic rate (BMR) in response to short-term thermal acclimation was assessed in the Laughing Dove (Streptopelia senegalensis), a common resident bird species distributed throughout most of southern Africa. I hypothesised that S. senegalensis would display flexibility in BMR over short time scales and that this flexibility would be reversible. Additionally, I hypothesised BMR to be repeatable, and that changes in BMR would be correlated with changes in organ mass. I tested these hypotheses by measuring BMR in three groups of 10 birds before and after a short-term (21 day) thermal acclimation period to one of three air temperatures (10o, 22o & 35oC). After acclimation the three temperature groups were randomly divided and reverseacclimated for another 21 days to one of the two thermal environments not yet experienced. After this reverse-acclimation period BMR was measured again. The dry masses of the stomach, kidney, heart, intestines, liver and pectoral muscles of acclimated birds were used to determine possible mechanistic correlates of BMR adjustments. Additionally, by monitoring BMR every 4-6 days during cold (10oC) and heat (35oC) acclimation I was able to assess the temporal dynamics of adjustments in BMR in response to short-term thermal acclimation. BMR was both flexible and reversible in S. senegalensis as a consistent relationship between BMR and acclimation air temperature was observed after acclimation and reverse-acclimation. BMR increased with decreasing acclimation temperature. Furthermore, a significant proportion (25%) of the observed variation in BMR was repeatable in the 22oC group in spite of the change in BMR induced by thermal acclimation. The mechanistic correlate of BMR adjustment in S. senegalensis appears to be metabolic intensity and not organ size, as the only organ to show a significant increase in size was the intestine of the acclimated 10oC group, which was significantly heavier than the intestine of the 22oC group. BMR also decreases in response to the reduction of flight and/or exercise. Since this reduction was not accompanied by a correlated change in organ mass or body mass, the reduction in BMR as a response to captivity appears to be linked to metabolic intensity of the organs and skeletal muscles. In S. senegalensis adjustments in BMR occur during the first 30 days of captivity and thermal acclimation. The response in BMR to acclimation temperature is clearly evident as BMR of the heat-acclimated group was significantly lower than the coldacclimated group after 21 days. During the response period, which lasts approximately 30 days, BMR adjusts as a mechanism to offset the costs of thermoregulation and habituation to captivity while other metabolic parameters such as body mass, body temperature, and minimum wet thermal conductance adjust to captivity and the thermal environment. After 30 days BMR of the cold and heat-acclimated groups converge on 0.68W, indicating that once the associated metabolic parameters adjust and stabilize in response to the thermal environment, BMR continues to adjust to captivity.

This dissertation seeks to reduce the energy consumption of steam stripping to regenerate aqueous amine used for CO₂ capture from coal-fired power plants. Rigorous rate-based models in Aspen Plus® were developed, and rate-based simulations were used for packed vapor/liquid separation units. Five main configurations with varying levels of complexity were evaluated with the two solvents. 8 m piperazine (PZ) always performed better than 9 m monoethanolamine (MEA). More complex flowsheets stripped CO₂ with higher efficiency due to the more reversible separation. Multi-stage flash configurations were competitive at their optimal lean loadings, but they had poor efficiency at low lean loading. The most efficient configuration was an interheated column, with more effective and distributed heat exchange. It had a secondary benefit of a cooler overhead temperature, so less water vapor exited with the CO₂. Using a rich loading of 0.40 mol CO₂/mol alkalinity in 8 m PZ, the optimal lean loading was 0.28 and the energy requirement was 30.9 kJ/mol CO₂. Case studies were also performed on cold rich bypass and the use of geothermal heat. When cold rich bypass is used with the 2-stage flash and 8 m PZ, it reduces equivalent work by 11% to 30.7 kJ/mol CO₂. PZ benefited the most from cold rich bypass because it had a higher water concentration in the overhead vapor than with MEA. In an advanced 2-stage flash with 8 m PZ, geothermal heat available from 150 down to 100 °C requires 35.5 kJ work/mol CO₂. The heat duty and equivalent work was higher than other optimized configurations, but it would be a valid option if separating the heat source from the steam cycle of a coal-fired power plant was highly valued. Pilot plant campaigns were simulated with the available thermodynamic models. Two campaigns with 8 m PZ were simulated within small deviation from the measured values. The average absolute errors in these campaigns were 2.5 and 2.7%. A campaign with 9 m MEA in a simple stripper demonstrated that the MEA model did not predict the solvent properties well enough to appropriately represent the pilot plant operation. / text

The aim of the work is the examination of the usage of idiomatic eglish verbs. Phrasal verbs are the derivatives derived according to the following pattern: V (verb) + pv (postverb) = Vpv (verb postverb). They are regarded as one more type of word formation. English phrasal verbs are divided into non-reversible, metaphoric, and metonymic. / Darbo tikslas yra idiominių anglų veiksmažodžių vartojimo tyrimas. Fraziniai veiksmažodžiai yra išvestiniai žodžiai, sudaromi pagal tokią schemą: V (veiksmažodis) + pv (postverbas) = Vpv (frazinis veiksmažodis). Jie yra laikomi dar viena žodžių darybos rūšimi. Fraziniai veiksmažodžiai yra suskirstyti į nereversiškus, metaforinius ir metoniminius.

The recent quantification of the reservoir of carbon held in permafrost soils has rekindled the concern that the terrestrial biosphere will transition from a carbon sink to a carbon source during the 21st century. This dissertation is a compilation of four modelling studies that investigate the permafrost carbon feedback, its consequences for the projected future behaviour of the carbon cycle, and the origins of the proportionally between cumulative CO$_2$ emissions and near surface temperature change. The dissertation is centred around five questions: 1) what is the strength and timing of the permafrost carbon feedback to climate change? 2) If anthropogenic CO2 emissions cease, will atmospheric CO2 concentration continue to increase? 3) Can climate warming be reversed using artificial atmospheric carbon-dioxide removal? 4) What are the underlying physical mechanisms that explain the existence in Earth system models of the proportionality between cumulative CO2 emissions and mean global near surface temperature change? And 5) can strong terrestrial carbon cycle feedbacks, such as the permafrost carbon feedback, disrupt this proportionality? By investigating the these questions using the University of Victoria Earth System Climate Model (UVic ESCM) and analytical mathematics the following conclusions are drawn: 1) The permafrost carbon feedback to climate change is simulated to have a strength of 0.25 C (0.1 to 0.75)C by the year 2100 CE independent of emission pathway followed in the 21st century. This range is contingent on the size of the permafrost carbon pool and the simulated model climate sensitivity. 2) If CO2 emissions were to suddenly cease, the UVic ESCM suggests that whether or not CO2 would continue to build up in the atmosphere is contingent on climate sensitivity and the concentration of non-CO2 greenhouse gasses in the atmosphere. For a given model climate sensitivity there is a threshold value of radiative forcing from non-CO2 greenhouse gasses above which CO2 will continue to build up in the atmosphere for centuries after cessation of anthropogenic CO2 emissions. For a UVic ESCM the threshold value for the Representative Concentration Pathway (RCP) derived emission scenarios is approximately 0.6 Wm^-2 of non-CO2 greenhouse gas radiative forcing. The consequences of being above this threshold value are mild, with the model projecting a further 11-22 ppmv rise in atmosphere CO2 concentration after emissions cease. 3) If technologies were developed and deployed to remove carbon from the atmosphere simulations with the UVic ESCM suggest that a Holocene-like climate could be restored by the end of the present millennium (except under a high climate sensitivity and high emission scenario). However, more carbon must be removed from the atmosphere than was originally emitted to it. 4) The proportionality between cumulative CO2 emissions and global mean temperature change seen in most Earth system model simulations appears to arises from two factors: I) the stability of the airborne fraction of emitted carbon provided by the ocean uptake of carbon begin nearly a function of CO2 emission rate; and II) the diminishing heat uptake by the oceans compensating for the reduced radiative forcing per unit mass CO2 at high atmospheric CO2 concentrations. 5) Strong terrestrial carbon cycle feedbacks can disrupt the proportionality between cumulative CO2 emissions and global mean temperature change. However, within the range of emission rates project for the RCPs the permafrost carbon feedback is not strong enough to disrupt the relationship. Overall, the addition of the permafrost carbon pool to the UVic ESCM alters model behaviour in ways that if representative of the natural world will make stabilizing climate or reversing climate change more difficult than has previously been foreseen. / Graduate / 0768 / 0373 / andrewhughmacdougall@gmail.com

The recent quantification of the reservoir of carbon held in permafrost soils has rekindled the concern that the terrestrial biosphere will transition from a carbon sink to a carbon source during the 21st century. This dissertation is a compilation of four modelling studies that investigate the permafrost carbon feedback, its consequences for the projected future behaviour of the carbon cycle, and the origins of the proportionally between cumulative CO$_2$ emissions and near surface temperature change. The dissertation is centred around five questions: 1) what is the strength and timing of the permafrost carbon feedback to climate change? 2) If anthropogenic CO2 emissions cease, will atmospheric CO2 concentration continue to increase? 3) Can climate warming be reversed using artificial atmospheric carbon-dioxide removal? 4) What are the underlying physical mechanisms that explain the existence in Earth system models of the proportionality between cumulative CO2 emissions and mean global near surface temperature change? And 5) can strong terrestrial carbon cycle feedbacks, such as the permafrost carbon feedback, disrupt this proportionality? By investigating the these questions using the University of Victoria Earth System Climate Model (UVic ESCM) and analytical mathematics the following conclusions are drawn: 1) The permafrost carbon feedback to climate change is simulated to have a strength of 0.25 C (0.1 to 0.75)C by the year 2100 CE independent of emission pathway followed in the 21st century. This range is contingent on the size of the permafrost carbon pool and the simulated model climate sensitivity. 2) If CO2 emissions were to suddenly cease, the UVic ESCM suggests that whether or not CO2 would continue to build up in the atmosphere is contingent on climate sensitivity and the concentration of non-CO2 greenhouse gasses in the atmosphere. For a given model climate sensitivity there is a threshold value of radiative forcing from non-CO2 greenhouse gasses above which CO2 will continue to build up in the atmosphere for centuries after cessation of anthropogenic CO2 emissions. For a UVic ESCM the threshold value for the Representative Concentration Pathway (RCP) derived emission scenarios is approximately 0.6 Wm^-2 of non-CO2 greenhouse gas radiative forcing. The consequences of being above this threshold value are mild, with the model projecting a further 11-22 ppmv rise in atmosphere CO2 concentration after emissions cease. 3) If technologies were developed and deployed to remove carbon from the atmosphere simulations with the UVic ESCM suggest that a Holocene-like climate could be restored by the end of the present millennium (except under a high climate sensitivity and high emission scenario). However, more carbon must be removed from the atmosphere than was originally emitted to it. 4) The proportionality between cumulative CO2 emissions and global mean temperature change seen in most Earth system model simulations appears to arises from two factors: I) the stability of the airborne fraction of emitted carbon provided by the ocean uptake of carbon begin nearly a function of CO2 emission rate; and II) the diminishing heat uptake by the oceans compensating for the reduced radiative forcing per unit mass CO2 at high atmospheric CO2 concentrations. 5) Strong terrestrial carbon cycle feedbacks can disrupt the proportionality between cumulative CO2 emissions and global mean temperature change. However, within the range of emission rates project for the RCPs the permafrost carbon feedback is not strong enough to disrupt the relationship. Overall, the addition of the permafrost carbon pool to the UVic ESCM alters model behaviour in ways that if representative of the natural world will make stabilizing climate or reversing climate change more difficult than has previously been foreseen. / Graduate / 2015-05-01 / 0768 / 0373 / andrewhughmacdougall@gmail.com