512 research outputs found
Life on the land : the interrelationship between identity and community in the Irish fiction of Maria Edgeworth, William Carleton and Charles Lever
No full textThis thesis examines and evaluates the response made by three
nineteenth century Irish writers of fiction to the most pressing
social problem of their time, namely: How might life on the land
be firmly established and maintained? The three writers concerned
— Maria Edgeworth, William Carleton and Charles Lever — are shown
to possess a common artistic vision, which is preserited as an answer
to the question posed. The answer consists of a demonstration of
how the resources of an enabling individual must blend with the
requirements of life on the land as it is.
By way of introduction, the significance of the theme for
both the literary and socio—political contexts of the period
(1800-1872) is described, and the problems of dealing with-nineteenth
century Irish fiction — problems concerned with its status
in the national cultural heritage, its variety and its artistic
characteristics — are outlined.
The four Irish novels of Maria Edgeworth are given a special
status in her overall output, and her handling of the theme in them
is considered as the prototype of her successors' manner of dealing
with it. Carleton and Lever are taken as portraying the Edgeworth
model under stress. Carleton's work is represented by a selection
of pieces from his Traits and Stories of the Irish Peasantry;
Lever's by three novels from the 1850's and '60's. All three
writers are located in their contemporary cultural milieux, and
their individual treatments of the theme are described and compared.
In conclusion, a general characterisation of the type of fiction
produced by the trio is offered, and a basis for its artistic
relationship to Irish fiction of more recent times is rehearsed.
The thesis facilitates a new periodisation of the history of
nineteenth century Irish fiction. It also offers a revised
conception of a tradition, of Irish fiction. These are the
contributions it makes to knowledge of the subject treated
Silicon Photonic Devices for Sensing, Switching, Polarization and Mode Control
No full textThis thesis starts with an investigation of the local oxidation of silicon (LOCOS) technique to fabricate submicron-size photonic waveguides. Next, the thesis shifts the focus theme from fabrication technology to device designs. The first class of silicon devices that was investigated in this thesis is microring resonator (MRR)-based devices, two of which are targeted for label-free evanescent field sensing. The last MRR-based device proposed is an all-optical switch using a ring-assisted Mach-Zehnder interferometer (RAMZI), which is the essential building block for on-chip silicon photonic circuits. The second class of silicon photonic devices investigated in this thesis is subwavelength grating (SWG) structures for polarization management. The SWG structure features the unique engineering capability of the waveguide effective index. The third class of silicon photonic devices investigated in this thesis is taper-based devices. The taper-based devices are first applied in polarization management. One design is a polarization rotator (PR) using a tapered amorphous silicon layer, which can effectively reduce the insertion loss; while the second design is a PSR based on a taper-etched directional coupler (DC). The thesis also presented a two-mode (de)multiplexer using a simple taper-etched DC, where the fabrication tolerance was greatly improved by the tapered design. All the devices mentioned above were thoroughly examined through numerical simulations. A selective set of devices were fabricated experimentally. For example, the LOCOS wire waveguides were fabricated at the Carleton University MicroFabrication Facility; the MMI coupled slotted MRRs and the TE-pass polarizer based on SWG waveguides have been fabricated using deep ultraviolet (DUV) lithography by the OpSIS and IMEC foundry services through the CMC Microsystems
Otomys thomasi Osgood 1910
No full textOtomys thomasi Osgood, 1910 Otomys thomasi; Osgood, 1910:9 (type locality—British East Africa [Kenya], Molo; holotype — FMNH 16698). Otomys thomasi thomasi; Dollman, 1915:153 (taxonomic revision, retained as species, de facto arrangement as nominate subspecies); Hollister, 1919:147 (faunal report, listed as valid species and subspecies); Allen, 1939:346 (listed as valid species and subspecies); Ellerman, 1941:323 (listed as valid species and subspecies). Otomys typus thomasi; Bohmann, 1952:41 (taxonomic revision, new name combination, retained as valid subspecies). Otomys typus [thomasi]; Misonne, 1974:33 (listed in synonymy without indication of rank); Musser & Carleton, 1993:682 (listed in synonymy without indication of rank). Otomys orestes [thomasi]; Musser & Carleton, 2005:1529 (new name combination, listed in synonymy without indication of rank); Carleton & Byrne, 2006:497 (taxonomic revision, retention of thomasi as junior synonym). Distribution. High plateau and mountains that form the western border of the Rift Valley (eastern branch), central Kenya; elevational range ca. 2450–2750 m. Specimens examined. KENYA: Uasin Gishu Plateau, 32 km N Eldama Ravine, 9,000 ft (2743 m) (USNM 164290); Molo (FMNH 16693–16695, 16698, 16699).Published as part of Taylor, Peter J., Lavrenchenko, Leonid A., Carleton, Michael D., Verheyen, Erik, Bennett, Nigel C., Oosthuizen, Carel J. & Maree, Sarita, 2011, Specific limits and emerging diversity patterns in East African populations of laminate-toothed rats, genus Otomys (Muridae: Murinae: Otomyini): Revision of the Otomys typus complex 3024, pp. 1-66 in Zootaxa 3024 (1) on pages 47-48, DOI: 10.11646/zootaxa.3024.1.1, http://zenodo.org/record/528058
The petrology of the J-M Reef Pd-Pt deposit and the Lower Banded series of the Stillwater Complex, Montana, USA
No full textThe J-M Reef, of the Lower Banded series (LBS) in the Neoarchean Stillwater Complex, is the highest-grade platinum group element (PGE) deposit on Earth. The J-M Reef is a ~1.5 m thick stratiform accumulation of high tenor disseminated sulfide and platinum group minerals hosted in coarse-grained heteradcumulates called the Reef Package. The grades and sulfide tenors of the reef vary from one part of the Stillwater Complex to another due to variable amounts of silicate and sulfide liquid equilibration. The cumulates in the LBS can be modeled by batch crystallization of a komatiitic parental melt contaminated by lower crustal rocks. Emplacement of crystal-bearing slurries produces the noritic and gabbronoritic cumulates that account for most of the rocks in the LBS. The olivine-bearing rocks of the LBS are modeled by infiltration and partial melting of footwall gabbronorites by an influx of hot, dense contaminated komatiitic parental melt. This infiltration and reaction process dissolves gabbronorite mush and crystallizes olivine. Dissolution of plagioclase crystals at smaller size fractions during reaction with the infiltrating melt, produces flatter, convex crystal size distributions in the Reef Package. The infiltration process that produces the olivine-bearing rocks in the LBS and the coarse-grained rock in the Reef Package, can also produce high PGE tenor sulfide mineralization. Mass balance calculations for S and Pd show that sulfides hosted within the footwall gabbronorite can be dissolved and upgraded by the incoming, sulfide-undersaturated and PGE-undepleted melt. This infiltration and upgrading of footwall disseminated sulfide has implications for the origin of other reef-type PGE deposits where erosional contacts are observed between the ore-hosting rocks and their footwall (e.g., the Merensky Reef of the Bushveld Complex). The top of the Reef Package, and the top of economic reef mineralization, is defined by a change in rock fabric known as the hanging wall contact. The hanging wall contact is determined by the change from the coarse-grained textures in the Reef Package to foliated, finer-grained cumulates in the hanging wall. This contact represents the most important marker horizon in mine operations because it is always present, even when the J-M Reef is not
Otomys zinki Bohmann 1943
No full textOtomys zinki Bohmann, 1943 Otomys typus zinki; Bohmann, 1943:153 (type locality— German East Africa [Tanzania], Kilimanjaro, Peters Hut, 3800 m; holotype —not seen; listed as “No. 548” in his private collection by Bohmann, 1943); Swynnerton and Hayman, 1951:321 (faunal report, listed as valid subspecies); Bohmann, 1952:41 (taxonomic revision, retained as valid subspecies). Otomys typus [zinki]; Misonne, 1974:33 (listed in synonymy without indication of rank); Musser & Carleton, 1993:682 (listed in synonymy without indication of rank). Otomys orestes [zinki]; Musser & Carleton, 2005:1528 (new name combination, listed in synonymy without indication of rank). Distribution. The species is limited in its distribution to Mt Kilimanjaro. Specimens examined. TANZANIA: Kilimanjaro (SM 4270, 4272, 4278, 4280); Mount Kilimanjaro East, Maundi Crater, grassland, 3270 m (RMCA 96.037.M-6801, 96.037.M-6802, 96.037.M-6803, 96.037.M-6804, 96.037.M-6805, 96.037.M-6801); Mount Kilimanjaro West, Londorosi, forest, 2350 m (96.037.M-6807, 96.037.M-6810); Mount Kilimanjaro West, Shira, moorland, 3000 m (96.037.M-6809); Mount Kilimanjaro, Kilimanjaro National Park, 13,100 ft (3993 m) (FMNH 174178–174180); Mount Kilimanjaro, Kilimanjaro National Park, 7 km N and 2.5 km W Maua, 8,100 ft (2469 m) (FMNH 174173, 174174).Published as part of Taylor, Peter J., Lavrenchenko, Leonid A., Carleton, Michael D., Verheyen, Erik, Bennett, Nigel C., Oosthuizen, Carel J. & Maree, Sarita, 2011, Specific limits and emerging diversity patterns in East African populations of laminate-toothed rats, genus Otomys (Muridae: Murinae: Otomyini): Revision of the Otomys typus complex 3024, pp. 1-66 in Zootaxa 3024 (1) on page 53, DOI: 10.11646/zootaxa.3024.1.1, http://zenodo.org/record/528058
Urban/rural source apportionment and intraurban source-based spatial analysis of Polycyclic Aromatic Hydrocarbons (PAH) and associated toxicity
No full textThis research identified and quantified source types contributing to ambient PAH and associated toxicity at the urban and intraurban scales, reflecting awareness of the variability in exposure toxicity and in source toxicity for PM-associated toxic pollutants. Source apportionment analysed vapour+particle PAH time-series data (2001-2010) from central site monitoring stations at urban (Hamilton, Toronto) and rural background (Egbert) sites in Southern Ontario, Canada. Receptor modeling by Positive Matrix Factorization (PMF) identified four source types: volatilized PAH/long-range transported coal combustion, vehicle traffic exhaust, space heating, biomass combustion. At Hamilton, local industry emissions were also identified, associated with iron/steel manufacturing. Apportionment of PAH toxicity using Benzo(a)Pyrene-toxicity equivalency factors identified traffic exhaust and local industry as ‘more toxic’ source types, contributing comparably little to ambient PAH yet disproportionately to PAH-associated toxicity. Intraurban investigation of PAH sources sampled vapour+particle PAH and PM2.5 from a dense network of >30 Hamilton sites over a two-week period in June-July and December 2009. Ambient PAH exhibited substantially greater spatial variability than PM2.5 and ‘hot spots’ of elevated pollutant levels were observed near/downwind of the business district and harbour-front. A combined PMF-Chemical Mass Balance (CMB) receptor modeling approach applied factors derived from the PMF model of Hamilton central site time-series data as ‘local source profiles’ in a CMB model of spatial field sampling data, explaining spatial variability observed for PAH and PAH toxicity in terms of sources. Contributions by space heating, volatilized PAH/transported coal combustion, wood combustion showed low intraurban variability, while vehicle traffic exhaust showed moderate variability, and local industry emissions contributed significantly only near the industrial harbour-front. Vehicle traffic exhaust contributed majority of PAH toxicity at all sites, even where ambient PAH concentrations were comparably low, and local industry emissions contributed significantly only near the industrial zone, explaining ‘toxicity hot spots’ as high contributions of local industry in addition to vehicle traffic. Findings recommend that efforts to reduce PAH exposures prioritize ‘more toxic’ source types such as vehicle traffic and local industry. PMF-CMB receptor modeling using local time-series PAH data to interpret intraurban variability in ambient PAH demonstrated a viable analysis method for other urban locations
Personality, performance, and the effects of stress on checkered pufferfish (Sphoeroides testudineus)
No full textFew studies focus on the mechanisms that regulate consistent individual-level differences in behaviour (i.e., personality) in wild animals, despite their potential evolutionary and ecological implications. I examined whether wild checkered pufferfish (Sphoeroides testudineus) have consistent individual-level differences in locomotor activity, threat-response behaviour, swimming ability, and puffing performance. I also evaluated the relationships between these personality and performance traits. Personality and performance were compared to movements in the field. In addition, I tested whether a treatment of the stress hormone cortisol would alter personality and performance. Pufferfish exhibited personalities but these were not associated with performance or recapture in the field. Performance was consistent between the lab and the natural enclosure but activity was not. The cortisol treatment did not modify personality or performance, which suggests that these traits do not represent a stress-coping syndrome. I conclude by recommending future directions for research on stress and personality in wild animals
The Effects of Dietary Nutrient Balance on Life-History Traits and Sexual Selection in the Field Cricket, Gryllus Veletis
No full textNutrition is an important driver of biological variation. Macronutrients such as protein and carbohydrates, and elemental nutrients such as phosphorus, are known to affect animal fitness traits. No study, however, has investigated the importance of phosphorus relative to dietary protein or carbohydrates, or their interactive effects, on animal performance. To advance our understanding of the impact of nutrition on individual fitness, my thesis examined the influence of dietary protein, carbohydrate, and phosphorus balance on fitness-related life-history traits, including those involved in intra- and inter-sexual selection, of Gryllus veletis field crickets. My findings revealed that adult lifespan, weight gain, males' acoustic mate attraction signals, and females' egg production were maximized on diets with different protein:carbohydrate ratios, such that not all fitness traits could simultaneously be maximized on the same diet. Similarly, juvenile females could not simultaneously maximize their growth, development rate, survival, and dispersal capability at adulthood on the same dietary protein:carbohydrate ratio. Adult males and females also had different optimal nutrient intake ratios for reproductive performance. My results support theoretical predictions for the condition-dependence of traits involved in inter- and intra-sexual selection; both male mate attraction signals, and female sexual responsiveness and preferences for such signals, were influenced by dietary protein:carbohydrate ratio. However, male aggressiveness in agonistic contests with rivals was not influenced by dietary nutrient balance. Contrary to my expectations, dietary phosphorus had little influence on fitness traits, with the exception of a negative influence of high phosphorus diets on male mate attraction signals. When given a choice between diets containing differing but complementary nutrient compositions, both adults and juveniles demonstrated an ability to regulate their protein and carbohydrate intakes, but not their phosphorus intake. These self-selected diets often represented a compromise between the differing nutrient requirements of multiple fitness traits. Overall, my findings suggest that environmental heterogeneity in nutrient availability is an important driver of variation in animal fitness, and highlight the importance of disentangling the influences of different nutrients on animal fitness traits
Novel Treatment Strategies for Major Depressive Disorder: Investigating Ketamine’s Antidepressant Effects and the Role of the c-Jun N-Terminal Kinase Pathway
No full textCurrent first-line treatments for depression, namely monoamine-based drugs such as SSRIs, take weeks to show any clinical effects, and they are only effective in 60-70% of patients. There is therefore an urgent need to develop more rapid and efficacious treatments. Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist often used as a dissociative anesthetic, has been found to have rapid (within hours) antidepressant effects, even in historically treatment resistant patients. Nevertheless, ketamine has its own limitations, such as unwanted side effects and abuse potential. The overarching goal of this thesis was to gain a better understanding of the antidepressant mechanisms of ketamine. Interestingly, we found that ketamine did not impact the typical stress hormone, corticosterone, nor did it modulate brain-region specific monoamine changes that were induced by acute (restraint) or systemic (lipopolysaccharide; LPS) stressors. However, ketamine did have anti-inflammatory actions, reducing interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α), and further still, repeated ketamine treatment promoted adult neurogenesis within the hippocampus. Notably, repeated ketamine also had an antidepressant-like behavioral effect that was still detectable 8 days after the final ketamine injection. In terms of potential mechanistic factors, ketamine increased active levels of the signaling factor c-Jun N-terminal kinase (JNK) within the cortex, and inhibition of JNK itself increased corticosterone levels. Intriguingly, JNK inhibition also modulated some stress-induced behavioral and monoaminergic changes, implying a diverse role for the protein. Overall, the data support a role for ketamine in neuroplasticity and immune function, and set the stage for future investigations into the pathways (i.e. JNK) associated with its antidepressant effects
Tame algebras: (on algorithms for solving vector space problems, II)
No full textRingel CM. Tame algebras: (on algorithms for solving vector space problems, II). In: Dlab V, Gabriel P, eds. Representation Theory I: Proceedings of the Workshop on the Present Trends in Representation Theory, Ottawa, Carleton University, August 13-18, 1979: No. 1. Lecture notes in mathematics. Vol 831. Berlin, Heidelberg: Springer; 1980: 137-287
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