The land of deep water lies in Ontario’s north, atop the boundless rock of the Shield. It holds the secret of an island once blossoming with copper ore. Here primordial elements dance in the ancient landscape and invite us to join them in their awakening. Liquid portals, layered ancient rock and plunging mine shafts unearth a cosmic order born of chaos. Myth, geology and alchemy all fuse together in defining this place. This thesis is a journey to centre of the Shield, through the deep water, rock and voids that encircle it. It is an expedition into the multiplicities of time through the poetic imagination. Here on the bridge to preconsciousness, we are invited in. At the heart lies Copperfields, a mine isolated on an island in Temagami. Once bearing some of the purest copper on Earth, it now sits abandoned amidst fragments of its former glory. The design proposed reclaims these elements and animates them as gateways to the dynamic Shield. In the folds of time, quivering between thought and the preconscious, a fiction rich in meaning and experience is offered up. Let us now embark on our journey to the centre of the Shield.

The inherent complexity of the natural world has long been a central theme in ecological research, as the patterns and processes that govern ecosystems can operate at multiple spatial and temporal scales. It is clear that to develop general ecological frameworks, we must consider many different factors at different scales, and incorporate ideas from other disciplines. This thesis touches on several of these ideas, first through an analysis of literature, and then with field research examining the role of broad-scale abiotic factors on lotic systems. To determine how integrated aquatic science is currently understood among different researchers, I provide an analysis on communication and exchange of ideas among various subfields in aquatic science. I show that there are clear divisions within the aquatic science literature, suggesting that there is progress to be made on the integration of methods and ideas. Next, I examine the impact of a large-scale geological feature, the Canadian Precambrian Shield, on abiotic conditions in lotic systems, and how these conditions in turn influence the species assemblages of aquatic organisms. This is addressed with both historical survey data, as well as contemporary data, and as a whole, incorporates ideas concerning the relative influence of regional versus local factors, the importance of historical factors on species distributions, and the relationship between the abiotic environment and biological communities. These analyses show that there are distinct fish and macroinvertebrate communities in Shield lotic systems compared to those found in nearby off-Shield sites, indicating that the Shield is an important broad-scale factor influencing local biological communities. This finding, in conjunction with previous knowledge on the influence of historical factors, provides further insight on the structuring of lotic fish and macroinvertebrate communities in Ontario.

The inherent complexity of the natural world has long been a central theme in ecological research, as the patterns and processes that govern ecosystems can operate at multiple spatial and temporal scales. It is clear that to develop general ecological frameworks, we must consider many different factors at different scales, and incorporate ideas from other disciplines. This thesis touches on several of these ideas, first through an analysis of literature, and then with field research examining the role of broad-scale abiotic factors on lotic systems. To determine how integrated aquatic science is currently understood among different researchers, I provide an analysis on communication and exchange of ideas among various subfields in aquatic science. I show that there are clear divisions within the aquatic science literature, suggesting that there is progress to be made on the integration of methods and ideas. Next, I examine the impact of a large-scale geological feature, the Canadian Precambrian Shield, on abiotic conditions in lotic systems, and how these conditions in turn influence the species assemblages of aquatic organisms. This is addressed with both historical survey data, as well as contemporary data, and as a whole, incorporates ideas concerning the relative influence of regional versus local factors, the importance of historical factors on species distributions, and the relationship between the abiotic environment and biological communities. These analyses show that there are distinct fish and macroinvertebrate communities in Shield lotic systems compared to those found in nearby off-Shield sites, indicating that the Shield is an important broad-scale factor influencing local biological communities. This finding, in conjunction with previous knowledge on the influence of historical factors, provides further insight on the structuring of lotic fish and macroinvertebrate communities in Ontario.

The land of deep water lies in Ontario’s north, atop the boundless rock of the Shield. It holds the secret of an island once blossoming with copper ore. Here primordial elements dance in the ancient landscape and invite us to join them in their awakening. Liquid portals, layered ancient rock and plunging mine shafts unearth a cosmic order born of chaos. Myth, geology and alchemy all fuse together in defining this place. This thesis is a journey to centre of the Shield, through the deep water, rock and voids that encircle it. It is an expedition into the multiplicities of time through the poetic imagination. Here on the bridge to preconsciousness, we are invited in. At the heart lies Copperfields, a mine isolated on an island in Temagami. Once bearing some of the purest copper on Earth, it now sits abandoned amidst fragments of its former glory. The design proposed reclaims these elements and animates them as gateways to the dynamic Shield. In the folds of time, quivering between thought and the preconscious, a fiction rich in meaning and experience is offered up. Let us now embark on our journey to the centre of the Shield.

Protective coloration such as aposematism and crypsis occurs in many insects but only a few species alter their defensive strategy during the same instar. We hypothesize the adult shield bug Graphosoma lineatum with an alternating black and non-melanised longitudinal striation exhibit such a change in defensive coloration. In Sweden, the non-melanised stripes of the pre-hibernation G. lineatum are pale brown and cryptic but they change during hibernation to red and aposematic. We have tested the adaptive functions of coloration of the two G. lineatum forms against bird predators. In Paper I we used great tits as predators and measured detection time of the two forms against a background of dry grass and plants, simulating late-summer conditions. We found that the birds took longer time to find the pale than the red form. Thus, the pale form of G. lineatum is more cryptic in a dry environment than the red form. In Paper II and III we used naïve predators and measured attack rate/latency on red and pale adults and fifth-instar larvae (black and brown) to investigate avoidance and generalisation between the stages. In Paper II domestic chicks initially found the red form most intimidating, but both adult forms are more intimidating than the larva. Moreover, there was a broad generalisation among forms. In Paper III naïve great tits did not find the red form significantly more aversive than the pale adult. Neither the chicks nor the tits showed any difference in the speed of avoidance learning between the two adult colour forms. In Paper IV the shieldbugs themselves were the main focus as we compared activity levels in the different colour forms and found that G. lineatum alters behaviour in accordance to their protective strategy. Thus they were significantly less active during the cryptic phase. Taken together, these experiments suggest that the pale brown adult invests in a cryptic strategy at the cost of reduced protection from aposematism, whereas the red adult benefits from aposematism at the cost of reduced camouflage. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Accepted.

Long-lived and short-lived volcanic vents often form in close proximity to one another. However, the processes that distinguish between these volcano types remain unknown. Here, I investigate the differences of long-lived (shield volcano) and short-lived (cinder cone) magmatic systems using two approaches. In the first, I use melt inclusion volatile contents for shield volcanoes and compare them to published data for cinder cones to investigate how shallow magma storage conditions differ between the two vent types in the Oregon Cascades. In the second, I model the primitive magmas that fed shield volcanoes and compare these compositions to those of nearby cinder cones to determine if the volcanoes are drawing magma from the same sources. The volatile concentrations suggest that long-lived and short-lived magmatic plumbing systems are distinct. Modeling of parental magmas and differentiation processes further suggest that long-lived and short-lived volcanoes have erupted lava from the same mantle magma source.

abstract: Olympus Mons is the largest volcano on Mars. Previous studies have focused on large scale features on Olympus Mons, such as the basal escarpment, summit caldera complex and aureole deposits. My objective was to identify and characterize previously unrecognized and unmapped small scale features to understand the volcanotectonic evolution of this enormous volcano. For this study I investigated flank vents and arcuate graben. Flank vents are a common feature on composite volcanoes on Earth. They provide information on the volatile content of magmas, the propagation of magma in the subsurface and the tectonic stresses acting on the volcano. Graben are found at a variety of scales in close proximity to Martian volcanoes. They can indicate flexure of the lithosphere in response to the load of the volcano or gravitation spreading of the edifice. Using Context Camera (CTX), High Resolution Imaging Science Experiment (HiRISE), Thermal Emission Imaging System (THEMIS), High Resolution Stereo Camera Digital Terrain Model (HRSC DTM) and Mars Orbiter Laser Altimeter (MOLA) data, I have identified and characterized the morphology and distribution of 60 flank vents and 84 arcuate graben on Olympus Mons. Based on the observed vent morphologies, I conclude that effusive eruptions have dominated on Olympus Mons in the Late Amazonian, with flank vents playing a limited role. The spatial distribution of flank vents suggests shallow source depths and radial dike propagation. Arcuate graben, not previously observed in lower resolution datasets, occur on the lower flanks of Olympus Mons and indicate a recent extensional state of stress. Based on spatial and superposition relationships, I have constructed a developmental sequence for the construction of Olympus Mons: 1) Construction of the shield via effusive lava flows.; 2) Formation of the near summit thrust faults (flank terraces); 3) Flank failure leading to scarp formation and aureole deposition; 4) Late Amazonian effusive resurfacing and formation of flank vents; 5) Subsidence of the caldera, waning volcanism and graben formation. This volcanotectonic evolution closely resembles that proposed on Ascraeus Mons. Extensional tectonism may continue to affect the lower flanks of Olympus Mons today. / Dissertation/Thesis / Masters Thesis Geological Sciences 2015

Orientador: Maria do Carmo Estanislau do Amaral / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-21T15:01:25Z (GMT). No. of bitstreams: 1 Costa_SuzanaMariadosSantos_M.pdf: 5413800 bytes, checksum: 0fbb691374cc80432664625fb24982bc (MD5) Previous issue date: 2012 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Mestrado / Biologia Vegetal / Mestre em Biologia Vegetal

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Dissipation is an inevitable property of a mechanical system and influences the dynamical behavior and device performance. It is, therefore, crucial to study and understand the sources of dissipation in mechanical systems in order to control the dissipation present in the system. These sources of dissipation can be broadly classified in two groups: extrinsic and intrinsic mechanisms. Extrinsic mechanisms are independent of material properties and influenced by the external properties of the system, such as geometry, pressure, and temperature. Intrinsic mechanisms on the other hand, are independent of external conditions and arise from the intrinsic properties of the device material, such as defects in the bulk and the surface of the material. In this work, we closely study two extreme limits of dissipation at the opposite ends of the spectrum. First, at the high dissipation limit where extrinsic mechanisms dominate dissipation, spectral properties of the thermal noise force giving rise to Brownian fluctuations of a continuous mechanical system — namely, a doubly clamped nanomechanical beam resonator — immersed in a viscous liquid are investigated. To this end, two separate sets of experiments are performed. The power spectral density (PSD) of the Brownian fluctuations of the resonator around its fundamental mode are measured at the center of the resonator. Then, the frequency-dependent linear response of the resonator is measured, again at its center, by driving it with a harmonic force, via an electrothermal transducer, that couples well to the fundamental mode. These two separate measurements are then used to determine the PSD of the Brownian force acting on the structure in its fundamental mode. The PSD of the force noise extracted from multiple resonators with varied lengths spanning a broad frequency range displays a ``colored spectrum'' and follows the viscous dissipation of a cylinder oscillating in a viscous liquid by virtue of the fluctuation-dissipation theorem. In the second application, which is at the ultra-low dissipation limit at low temperature where intrinsic mechanisms dominate dissipation, we design and fabricate high-frequency aluminum nitride (AlN) piezo-optomechanical resonators. Furthermore, an acoustic radiation shield consisting of periodic phononic crystals is designed and implemented to further decrease dissipation. Fabrication and design of both the optomechanical cavity and phononic crystals are discussed in detail. Room temperature characterization of the ring resonator is presented and out-of-plane thickness mode of the AlN resonators has been identified. With microwave mechanical frequency and high Quality factor mechanical response, these resonators can be cooled down to quantum ground state with direct cooling methods such as dilution fridge cooling. These type of resonators can achieve efficient conversion between electrical, optical, and mechanical signals which can be utilized for quantum information science and sensing applications in the field of nanoelectromechanical systems. / 2023-09-24T00:00:00Z