964 resultados para Geology of Newfoundland.


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The growing popularity of dog parks has created an opportunity to learn more about interactions between companion dogs. Dog-dog behaviour in a public off-leash dog park was described and analyzed using a motivationally-neutral approach. I observed focal dogs from park entry for 400 s and constructed activity time budgets (percentages of time spent with dogs, humans, etc.); rates of socially-relevant dog behaviours (e.g., snout-muzzle contact, physical contact) were also calculated. On average, focal dogs spent 50% of their time alone, nearly 40% with other dogs and 11% in other activities; time with dogs decreased and time alone increased over the first six minutes. Some behaviours were very frequent (i.e., more than 90% of focal dogs initiated and received snout-muzzle contact to the anogenital and head areas, while others were rare (i.e., 9% and 12% of focal dogs initiated and received lunge approaches, respectively). Dog density and focal dog age, sex, neuter status, and size were found to influence some behavioural variables. Future studies should continue to investigate the diverse range of canid behaviours and factors that influence social behaviours in dog park settings.

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Patient satisfaction with health care is an important indicator of quality services and has been related to positive health outcomes. Because little is known about whether adolescents with physical disabilities are satisfied with the services they receive, the current study investigated the extent to which adolescents are satisfied with health care services, aspects of care adolescents identify as important to their satisfaction, similarities between adolescent and parent perceptions of care, and the relationship between adolescent perceptions of care and their intentions to adhere to treatment recommendations. Following recruitment from a pediatric health center, adolescents and their parents (n = 42) completed questionnaires to assess their perceptions regarding various aspects of health care services. Participants were very satisfied with services received; interpersonal aspects of care were very important to them. Adolescents’ satisfaction was not predictive of their intentions to adhere to treatment recommendations and their perspectives differed from those of their parents.

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Structure, energetics and reactions of ions in the gas phase can be revealed by mass spectrometry techniques coupled to ions activation methods. Ions can gain enough energy for dissociation by absorbing IR light photons introduced by an IR laser to the mass spectrometer. Also collisions with a neutral molecule can increase the internal energy of ions and provide the dissociation threshold energy. Infrared multiple photon dissociation (IRMPD) or sustained off-resonance irradiation collision-induced dissociation (SORI-CID) methods are combined with Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometers where ions can be held at low pressures for a long time. The outcome of ion activation techniques especially when it is compared to the computational methods results is of great importance since it provides useful information about the structure, thermochemistry and reactivity of ions of interest. In this work structure, energetics and reactivity of metal cation complexes with dipeptides are investigated. Effect of metal cation size and charge as well as microsolvation on the structure of these complexes has been studied. Structures of bare and hydrated Na and Ca complexes with isomeric dipeptides AlaGly and GlyAla are characterized by means of IRMPD spectroscopy and computational methods. At the second step unimolecular dissociation reactions of singly charged and doubly charged multimetallic complexes of alkaline earth metal cations with GlyGly are examined by CID method. Also structural features of these complexes are revealed by comparing their IRMPD spectra with calculated IR spectra of possible structures. At last the unimolecular dissociation reactions of Mn complexes are studied. IRMPD spectroscopy along with computational methods is also employed for structural elucidation of Mn complexes. In addition the ion-molecule reactions of Mn complexes with CO and water are explored in the low pressures obtained in the ICR cell.

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The health utilization and death rates were captured for the family members of disabled individuals over a fifteen-year period to determine if exposure to disability in the family manifests poor health outcomes. Data from the Newfoundland Adult Health Survey (1995) was linked to fifteen years, 1995- 2010, of provincial health administrative data including hospital data, physician claims, and death records from the provincial health care system. The health records and survey data were analyzed in relation to the disability exposure burden experienced when a family member is disabled. The level of disability exposure burden was quantified based on the addition of individual disability scores for each family member. Disability exposure burden was associated with increased number of hospital separations, total hospitalization days and the number of physician visits, both General Practitioner and Specialist (p<0.1) but there was no association between death (p>0.1) and disability exposure burden. Family members of disabled individuals experienced increased rates of hospital separations, hospitalization days, and physician visits suggesting that deleterious health outcomes may be introduced when individuals are exposed to disability in the family unit.

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This thesis analyses the potential of wood biochar as an adsorbent in removal of sulphate from produced water. In worldwide offshore oil and gas industry, a large volume of waste water is generated as produced water. Sulphur compounds present in these produced water streams can cause environmental problems, regulatory problems and operational issues. Among the various sulphur removal technologies, the adsorption technique is considered as a suitable method since the design is simple, compact, economical and robust. Biochar has been studied as an adsorbent for removal of contaminants from water in a number of studies due to its low cost, potential availability, and adsorptive characteristics. In this study, biochar produced through fast pyrolysis of bark, hardwood sawdust, and softwood sawdust were characterized through a series of tests and were analysed for adsorbent properties. Treating produced water using biochar sourced from wood waste is a two-fold solution to environmental problems as it reduces the volume of these wastes. Batch adsorption tests were carried out to obtain adsorption capacities of each biochar sample using sodium sulphate solutions. The highest sulphur adsorption capacities obtained for hardwood char, softwood char and bark char were 11.81 mg/g, 9.44 mg/g, and 7.94 mg/g respectively at 10 °C and pH=4. The adsorption process followed the second order kinetic model and the Freundlich isotherm model. Adsorption reaction was thermodynamically favourable and exothermic. The overall analysis concludes that the wood biochar is a feasible, economical, and environmental adsorbent for removal of sulphate from produced water.

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This thesis explores the character of Hamlet in Shakespeare's same-titled work in the light of certain aspects of stoicism and medieval Christian philosophy. Throughout the course of the play we see Hamlet struggling with his thoughts. At first he deliberates without taking action as a consequence of his reasoning, but in the later stages of the play he gives in to passion, which ultimately leads to his own demise. The thesis gives an account of certain aspects of both philosophies that are displayed in the play and shows how those ideas influence the character of Hamlet and contextualize his personal tragedy. Hamlet fails to follow the philosophies that he praises and to grow as a character by overcoming his passions over the course of the play.

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A cemetery associated with the St. John’s Royal Naval Hospital, NL (~1725-1825) was partially excavated in 1979, uncovering the skeletal remains of at least 21 individuals. Isotopic analyses (δ¹³Cvpdb, δ¹⁵Nair, δ¹⁸Ovpdb, and ⁸⁷Sr/⁸⁶Sr) were used to examine the diet and geographic origins of these individuals and compare them with recent results from other British Naval cemeteries. Their origins according to enamel carbonates and ⁸⁷Sr/⁸⁶Sr are mainly consistent with the British Isles and the bone collagen values were largely consistent with naval rations. There was some variability in δ¹⁵Nair and δ¹³Cvpdb values, suggesting different social classes and the consumption of C₄ foods associated with North America. While this study has highlighted deficiencies in the ability of isotopic analyses to define the variability within naval rations, it is the first to examine origins of early modern naval sailors isotopically, as well as the experiences of these sailors within the context of Newfoundland.

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This thesis reports on a novel method to build a 3-D model of the above-water portion of icebergs using surface imaging. The goal is to work towards the automation of iceberg surveys, allowing an Autonomous Surface Craft (ASC) to acquire shape and size information. After collecting data and images, the core software algorithm is made up of three parts: occluding contour finding, volume intersection, and parameter estimation. A software module is designed that could be used on the ASC to perform automatic and fast processing of above-water surface image data to determine iceberg shape and size measurement and determination. The resolution of the method is calculated using data from the iceberg database of the Program of Energy Research and Development (PERD). The method was investigated using data from field trials conducted through the summer of 2014 by surveying 8 icebergs during 3 expeditions. The results were analyzed to determine iceberg characteristics. Limitations of this method are addressed including its accuracy. Surface imaging system and LIDAR system are developed to profile the above-water iceberg in 2015.

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Produced water is a by-product of offshore oil and gas production, and is released in large volumes when platforms are actively processing crude oil. Some pollutants are not typically removed by conventional oil/water separation methods and are discharged with produced water. Oil and grease can be found dispersed in produced water in the form of tiny droplets, and polycyclic aromatic hydrocarbons (PAHs) are commonly found dissolved in produced water. Both can have acute and chronic toxic effects in marine environments even at low exposure levels. The analysis of the dissolved and dispersed phases are a priority, but effort is required to meet the necessary detection limits. There are several methods for the analysis of produced water for dispersed oil and dissolved PAHs, all of which have advantages and disadvantages. In this work, EPA Method 1664 and APHA Method 5520 C for the determination of oil and grease will be examined and compared. For the detection of PAHs, EPA Method 525 and PAH MIPs will be compared, and results evaluated. APHA Method 5520 C Partition-Infrared Method is a liquid-liquid extraction procedure with IR determination of oil and grease. For analysis on spiked samples of artificial seawater, extraction efficiency ranged from 85 – 97%. Linearity was achieved in the range of 5 – 500 mg/L. This is a single-wavelength method and is unsuitable for quantification of aromatics and other compounds that lack sp³-hybridized carbon atoms. EPA Method 1664 is the liquid-liquid extraction of oil and grease from water samples followed by gravimetric determination. When distilled water spiked with reference oil was extracted by this procedure, extraction efficiency ranged from 28.4 – 86.2%, and %RSD ranged from 7.68 – 38.0%. EPA Method 525 uses solid phase extraction with analysis by GC-MS, and was performed on distilled water and water from St. John’s Harbour, all spiked with naphthalene, fluorene, phenanthrene, and pyrene. The limits of detection in harbour water were 0.144, 3.82, 0.119, and 0.153 g/L respectively. Linearity was obtained in the range of 0.5-10 g/L, and %RSD ranged from 0.36% (fluorene) to 46% (pyrene). Molecularly imprinted polymers (MIPs) are sorbent materials made selective by polymerizing functional monomers and crosslinkers in the presence of a template molecule, usually the analytes of interest or related compounds. They can adsorb and concentrate PAHs from aqueous environments and are combined with methods of analysis including GC-MS, LC-UV-Vis, and desorption electrospray ionization (DESI)- MS. This work examines MIP-based methods as well as those methods previously mentioned which are currently used by the oil and gas industry and government environmental agencies. MIPs are shown to give results consistent with other methods, and are a low-cost alternative improving ease, throughput, and sensitivity. PAH MIPs were used to determine naphthalene spiked into ASTM artificial seawater, as well as produced water from an offshore oil and gas operation. Linearity was achieved in the range studied (0.5 – 5 mg/L) for both matrices, with R² = 0.936 for seawater and R² = 0.819 for produced water. The %RSD for seawater ranged from 6.58 – 50.5% and for produced water, from 8.19 – 79.6%.

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The sudden hydrocarbon influx from the formation into the wellbore poses a serious risk to the safety of the well. This sudden influx is termed a kick, which, if not controlled, may lead to a blowout. Therefore, early detection of the kick is crucial to minimize the possibility of a blowout occurrence. There is a high probability of delay in kick detection, apart from other issues when using a kick detection system that is exclusively based on surface monitoring. Down-hole monitoring techniques have a potential to detect a kick at its early stage. Down-hole monitoring could be particularly beneficial when the influx occurs as a result of a lost circulation scenario. In a lost circulation scenario, when the down-hole pressure becomes lower than the formation pore pressure, the formation fluid may starts to enter the wellbore. The lost volume of the drilling fluid is compensated by the formation fluid flowing into the well bore, making it difficult to identify the kick based on pit (mud tank) volume observations at the surface. This experimental study investigates the occurrence of a kick based on relative changes in the mass flow rate, pressure, density, and the conductivity of the fluid in the down-hole. Moreover, the parameters that are most sensitive to formation fluid are identified and a methodology to detect a kick without false alarms is reported. Pressure transmitter, the Coriolis flow and density meter, and the conductivity sensor are employed to observe the deteriorating well conditions in the down-hole. These observations are used to assess the occurrence of a kick and associated blowout risk. Monitoring of multiple down-hole parameters has a potential to improve the accuracy of interpretation related to kick occurrence, reduces the number of false alarms, and provides a broad picture of down-hole conditions. The down-hole monitoring techniques have a potential to reduce the kick detection period. A down-hole assembly of the laboratory scale drilling rig model and kick injection setup were designed, measuring instruments were acquired, a frame was fabricated, and the experimental set-up was assembled and tested. This set-up has the necessary features to evaluate kick events while implementing down-hole monitoring techniques. Various kick events are simulated on the drilling rig model. During the first set of experiments compressed air (which represents the formation fluid) is injected with constant pressure margin. In the second set of experiments the compressed air is injected with another pressure margin. The experiments are repeated with another pump (flow) rate as well. This thesis consists of three main parts. The first part gives the general introduction, motivation, outline of the thesis, and a brief description of influx: its causes, various leading and lagging indicators, and description of the several kick detection systems that are in practice in the industry. The second part describes the design and construction of the laboratory scale down-hole assembly of the drilling rig and kick injection setup, which is used to implement the proposed methodology for early kick detection. The third part discusses the experimental work, describes the methodology for early kick detection, and presents experimental results that show how different influx events affect the mass flow rate, pressure, conductivity, and density of the fluid in the down-hole, and the discussion of the results. The last chapter contains summary of the study and future research.

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In this thesis, we introduce DeReEs-4v, an algorithm for unsupervised and automatic registration of two video frames captured depth-sensing cameras. DeReEs-4V receives two RGBD video streams from two depth-sensing cameras arbitrary located in an indoor space that share a minimum amount of 25% overlap between their captured scenes. The motivation of this research is to employ multiple depth-sensing cameras to enlarge the field of view and acquire a more complete and accurate 3D information of the environment. A typical way to combine multiple views from different cameras is through manual calibration. However, this process is time-consuming and may require some technical knowledge. Moreover, calibration has to be repeated when the location or position of the cameras change. In this research, we demonstrate how DeReEs-4V registration can be used to find the transformation of the view of one camera with respect to the other at interactive rates. Our algorithm automatically finds the 3D transformation to match the views from two cameras, requires no human interference, and is robust to camera movements while capturing. To validate this approach, a thorough examination of the system performance under different scenarios is presented. The system presented here supports any application that might benefit from the wider field-of-view provided by the combined scene from both cameras, including applications in 3D telepresence, gaming, people tracking, videoconferencing and computer vision.

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The main focus of this thesis is to address the relative localization problem of a heterogenous team which comprises of both ground and micro aerial vehicle robots. This team configuration allows to combine the advantages of increased accessibility and better perspective provided by aerial robots with the higher computational and sensory resources provided by the ground agents, to realize a cooperative multi robotic system suitable for hostile autonomous missions. However, in such a scenario, the strict constraints in flight time, sensor pay load, and computational capability of micro aerial vehicles limits the practical applicability of popular map-based localization schemes for GPS denied navigation. Therefore, the resource limited aerial platforms of this team demand simpler localization means for autonomous navigation. Relative localization is the process of estimating the formation of a robot team using the acquired inter-robot relative measurements. This allows the team members to know their relative formation even without a global localization reference, such as GPS or a map. Thus a typical robot team would benefit from a relative localization service since it would allow the team to implement formation control, collision avoidance, and supervisory control tasks, independent of a global localization service. More importantly, a heterogenous team such as ground robots and computationally constrained aerial vehicles would benefit from a relative localization service since it provides the crucial localization information required for autonomous operation of the weaker agents. This enables less capable robots to assume supportive roles and contribute to the more powerful robots executing the mission. Hence this study proposes a relative localization-based approach for ground and micro aerial vehicle cooperation, and develops inter-robot measurement, filtering, and distributed computing modules, necessary to realize the system. The research study results in three significant contributions. First, the work designs and validates a novel inter-robot relative measurement hardware solution which has accuracy, range, and scalability characteristics, necessary for relative localization. Second, the research work performs an analysis and design of a novel nonlinear filtering method, which allows the implementation of relative localization modules and attitude reference filters on low cost devices with optimal tuning parameters. Third, this work designs and validates a novel distributed relative localization approach, which harnesses the distributed computing capability of the team to minimize communication requirements, achieve consistent estimation, and enable efficient data correspondence within the network. The work validates the complete relative localization-based system through multiple indoor experiments and numerical simulations. The relative localization based navigation concept with its sensing, filtering, and distributed computing methods introduced in this thesis complements system limitations of a ground and micro aerial vehicle team, and also targets hostile environmental conditions. Thus the work constitutes an essential step towards realizing autonomous navigation of heterogenous teams in real world applications.

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Bicellar lipid mixture dispersions progressively coalesce to larger structures on warming. This phase behaviour is particularly sensitive to interactions that perturb bilayer properties. In this study, ²H NMR was used to study the perturbation of bicellar lipid mixtures by two peptides (SP-B₆₃₋₇₈, a lung surfactant protein fragment and Magainin 2, an antimicrobial peptide) which are structurally similar. Particular attention was paid to the relation between peptide-induced perturbation and lipid composition. In bicellar dispersions containing only zwitterionic lipids (DMPC-d₅₄/DMPC/DHPC (3:1:1)) both peptides had little to no effect on the temperature at which coalescence to larger structures occurred. Conversely, in mixtures containing anionic lipids (DMPC-d₅₄/DMPG/DHPC (3:1:1)), both peptides modified bicellar phase behaviour. In mixtures containing SP-B₆₃₋₇₈, the presence of peptide decreased the temperature of the ribbon-like to extended lamellar phase transition. The addition of Magainin 2 to DMPCd₅₄/ DMPG/DHPC (3:1:1) mixtures, in contrast, increased the temperature of this transition and yielded a series of spectra resembling DMPC/DHPC (4:1) mixtures. Additional studies of lipid dispersions containing deuterated anionic lipids were done to determine whether the observed perturbation involved a peptide-induced separation of zwitterionic and anionic lipids. Comparison of DMPC/DMPG-d₅₄/DHPC (3:1:1) and DMPC-d₅₄/DMPG/DHPC (3:1:1) mixtures showed that DMPC and DMPG occupy similar environments in the presence of SP-B₆₃₋₇₈, but different lipid environments in the presence of Magainin 2. This might reflect the promotion of anionic lipid clustering by Magainin 2. These results demonstrate the variability of mechanisms of peptide-induced perturbation and suggest that lipid composition is an important factor in the peptide-induced perturbation of lipid structures.