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Physical barriers are known to limit species' ranges, but, in the absence of physical barriers, what prevents adaptation and expansion at the periphery? Genetic influence from central populations may prevent adaptation to ecological barriers by swamping peripheral populations with suboptimal genes. If this is the case, then isolation may enable local adaptation and further range expansion. Barriers such as rivers provide ideal tests of the influence of gene flow and may explain differences in range sizes. This study investigates northern range limitations and phylogeography of the Northern Two-lined ( Eurycea bislineata) and Northern Dusky (Desmognathus fuscus ) stream salamanders. Phylogeographic patterns of populations throughout Quebec and Labrador were investigated by sequencing portions of cytochrome b and 12S rRNA mitochondrial DNA genes. Interpopulation divergence was low for both species, however, unique genetic haplotypes and morphological variation on the north shore of the St. Lawrence indicate that the river is acting as a barrier to gene flow.

The present study quantifies electromyographic variables in one and two degree of freedom elbow movements involving flexion/extension and pronation/supination, in order to understand the associated central commands. Agonist burst magnitude varied with motion in a second degree of freedom for some muscles but not for others. In movements for which a biarticular muscle acted as agonist in two degrees of freedom, agonist burst magnitudes were approximately the sum of the magnitudes in the component movements. Agonist burst magnitude varied with motion in a second degree of freedom for some, but not all, monoarticular muscles. When biarticular muscles acted as agonist in one degree of freedom and antagonist in the other, the muscle often displayed both components simultaneously. The additivity of EMG burst magnitudes in two degree of freedom movements and the presence of both agonist and antagonist bursts in a muscle suggest that central commands associated with motion in individual degrees of freedom are superimposed in producing two degree of freedom movements.

The construction of 3D models of real-world scenes using non-contact methods is an important problem in computer vision. Some of the more successful methods belong to a class of techniques called structured light illumination (SLI). While SLI methods are generally very successful, there are cases where their performance is poor. Examples include scenes with a high dynamic range in albedo or scenes with strong interreflections. These scenes are referred to as optically challenging environments. The work in this dissertation is aimed at improving SLI performance in optically challenging environments. A new method of high dynamic range imaging (HDRI) based on pixel-by-pixel Kalman filtering is developed. Using objective metrics, it is show to achieve as much as a 9.4 dB improvement in signal-to-noise ratio and as much as a 29% improvement in radiometric accuracy over a classic method. Quality checks are developed to detect and quantify multipath interference and other quality defects using phase measuring profilometry (PMP). Techniques are established to improve SLI performance in the presence of strong interreflections. Approaches in compressed sensing are applied to SLI, and interreflections in a scene are modeled using SLI. Several different applications of this research are also discussed.

The communication range between a civilian Unmanned Aerial Vehicle (UAV) and a Ground Control Station (GCS) is affected by the government regulations that determine the use of frequency bands and constrain the amount of power in those frequencies. The application of multiple UAVs in search and rescue operations for example demands a reliable, long-range inter-UAV communication. The inter-UAV communication is the ability of UAVs to exchange data among themselves, thus forming a network in the air. This ability could be used to extend the range of communication by using a decentralized routing technique in the network. To provide this ability to a fleet of autonomous dirigible UAVs being developed at the University of Ottawa, a new communication framework was introduced and implemented. Providing a true mesh networking based on a novel routing protocol, the framework combines long-range radios at 900 MHz Industrial, Scientific and Medical (ISM) band with the software integrated into the electronics platform of each dirigible. With one radio module per dirigible the implemented software provides core functionalities to each UAV, such as exchanging flight control commands, telemetry data, and photos with any other UAV in a decentralized network or with the GCS. We made use of the advanced networking tools of the radio modules to build capabilities into the software for route tracing, traffic prioritization, and minimizing self-interference. Initial test results showed that without acknowledgements, packets can be received in the wrong order and cause errors in the transmission of photos. In addition, a transmission in a presence of a third broadcasting node slows down by 4-6 times. Based on these results our software was improved to control to flow of transmit data making the fragmentation, packetization, and reassembly of photos more reliable. Currently, using radios with half-wavelength dipole antennas we can achieve a one-hop communication range of up to 5 km with the radio frequency line-of-sight (RF LOS). This can be extended further by adding as many radio nodes as needed to act as intermediate hops.

Femoro-Acetabular Impingement (FAI) is a hip joint disease which affects and impairs the range of hip motion during performing activities of daily living, jogging, walking, or climbing stairs due to the bony abnormalities of the joint. Ballet dancers and athletes (e.g. gymnasts and hockey players) put their hips at the risk of FAI by extremely moving the hip mainly by excessively rotating the joint. In this research, we introduce a visualization system which helps surgeons to analyze the range of hip motions as well as to have a better communication with patients. These goals are achieved by presenting three dimensional (3D) visualizations of motion envelope by examining the maximum possible rotation of the digital hip bones. Our computer simulation system estimates, analyzes and visualizes the maximum hip range of motion (ROM) for the constructed 3D bone models that are extracted from Magnetic Resonance Images (MRI) after segmenting the bones. These tasks are accomplished by first calculating Hip Joint Center (HJC) which is center of rotation of femoral head on the 3D segmented MRI models followed by simulating hip motions with examining impingement between the femur and the acetabulum using our collision detection system. In our collision detection system, surfaces of femoral head and acetabulum bones are sampled in the spherical coordinates based on rasterization and interpolation. Then, the distance between the femoral head and acetabulum are computed to prevent impingement between them. The maximum motion degree of femur bone within depression of acetabulum in every direction during the digital simulation shows the ROMs of the inputted MRI of the hip joint. Six primary plane motions (flexion/extension, abduction/adduction and internal/external rotation) as well as various combinations of these motions (maximum rotation of the hip between every two rotational movements) and successive movements (maximum rotational movement of the hip per another rotational movement) are simulated and analyzed along with 3D visualization of estimated range of these motions. Generally, the ROM differs by some factors such as age, gender, ethnicity, and geographic location. For instance, newborns up to age two have considerably greater motion in hip flexion and hip abduction than adults. Our system by 3D visualization of motion envelope will provide a platform to understand quicker and better the effect of bony morphology of the hip joint on the possible ROM. We also examine the long-standing question about moving center of rotation related to ROM. We found out the ROM becomes bigger especially when the center moves outward to the direction of acetabulum axis. This thesis does not consider the effect of muscle and other surrounding connective tissue on the hip ROM since they can be altered significantly by physical training to show the potential of maximum ROM. For example a ballerina has a bigger ROM leading a bigger motion envelope compared with non-dancers. Hence we visualize the range of joint motions and their envelopes that are obtained from the osseous anatomy of the hip joint. The osseous anatomy of the joint is the most fundamental and permanent factor of ROM which indicates the maximum motion that the joint can achieve if the muscle and other connective tissues are perfectly trained.

Scimitar Glacier originates below the northeast face of Mt. Waddington in the southern British Columbia Coast Mountains and flows 18 km down valley to calve into a proglacial lake. The purpose of this research was to describe the late Holocene glacier history of Scimitar Glacier using stratigraphic analysis in conjunction with dendroglaciologic and radiocarbon dating techniques. Downwasting of the glacier surface has exposed stacked till units separated by wood-bearing horizons in the proximal slopes of lateral moraines flanking the glacier at several locations. Historical moraine collapse and erosional breaching has also revealed the remains of standing trees buried in sediments from a lake originally ponded against the distal moraine slope. Radiocarbon dating of detrital wood remains revealed that Scimitar Glacier expanded down-valley at least three times in the late Holocene. The earliest period of expansion occurred 3167-2737 cal yr BP in association with the regional Tiedemann Advance. Following this the glacier receded and downwasted prior to advancing to reconstruct the lateral moraine in 1568-1412 cal yr BP during the First Millennial Advance. The most recent phase of moraine construction was initiated during late Little Ice Age glacial expansion before 1742 AD and extended until at least 1851 AD, after which Scimitar Glacier began to recede and downwaste. Field investigations at Scimitar Glacier allowed for the construction of a late Holocene history of glacier expansion and lateral moraine construction that spans the last 3000 years. This record is comparable to that recorded at other glaciers in this region, and confirms the long-term relationship between regional climate trends and glacier behaviour in this setting. / Graduate

<p> The United States increasingly calls upon elite teams of Special Operations Forces, like the Navy SEALs, to respond to the evolving asymmetric threats posed by terrorists and extremists. These teams must have the capacity to adapt as a collective unit in the most dynamic circumstance. This research explored the nature of collective adaptation by these exceptional action teams using a qualitative case study methodology and a lens of complexity theory. Specifically, data gathered from official documents and interviews with retired Navy SEALs expanded the understanding of dynamic instability as it relates to team adaptation in uncertain environments. A greater understanding of this phenomenon contributed to the scholarly literature by identifying and describing the critical factors used by teams to promote adaptive capacity through the appropriate usage of structure and innovative flexibility in a dynamically changing situation. The study produced the following conclusions: 1. Individuals in an action team mentally reference a combination of general simple rules and situation-specific simple rules when they adapt in an uncertain environment. &bull; Varying application of different types of simple rules correspond with different levels of environmental uncertainty. &bull; Simple rules provide the basis for a shared cognitive structure that enables greater collective adaptation. 2. Previous experience plays an important role in the adaptive capacity of an action team. &bull; Experience provides an individual with context to determine how simple rules can and should be applied. &bull; Experience strengthens the relationship (trust and familiarity) between team members which allows them to adapt more quickly and effectively as a collective. 3. Relationships between team members, grounded in previous experience and a shared culture, play an important role in the adaptive capacity of an action team. &bull; Trust between team members gives each individual the freedom and permission to take initiative and adapt as necessary. &bull; Familiarity between team members enables the action team to collectively adapt more quickly and effectively because they can predict how another teammate will react given a specific set of parameters without the need for extensive communication. 4. The ability of individual team members to control emotions, slow and simplify reactions, and focus communication promotes more effective adaptation by an action team in an uncertain environment. &bull; Individual decision-making is enhanced when individuals are able to control their reactions and react calmly in the midst of an uncertain environment. &bull; As environmental uncertainty increases, individuals who react by slowing down and simplifying their actions are capable of more effective adaptation. &bull; In an uncertain environment, action teams that focus communication, reduce potential distractions for team members. This reduced, but effective communication is possible because of trust and familiarity between team members. 5. An action team's ability to adapt is dependent upon its dynamic instability (the interplay between morphostatic and morphogenetic factors). &bull; Morphostatic factors that promote structure include simple rules, selection of team members, familiarity between team members, and perpetuation of a structured culture that regulates behavior. &bull; Morphogenetic factors that promote flexibility include previous experience, distributed leadership, trust between team members, and perpetuation of a permissive culture that encourages innovation.</p>

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