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Background: Wound healing is a complicated mechanism that includes inflammatory, proliferative and remodelling stages. Platelet rich plasma (PRP) is a small volume of blood plasma fortified with platelets and growth factors that enhance the healing by stimulating angiogenesis and formation of granulation tissue. Methods: The present study was performed to evaluate the effect of autologous and homologous platelet rich plasma on full thickness dermatological reconstructive surgery in dogs. The dogs were divided in two groups A and B, each with four clinical cases. In groups A and B, autologous and homologous PRP was used respectively as skin graft augmentation. The macroscopic parameters of the study included colour, edema, exudation and histopathological parameters included acute inflammation, fibroblast proliferation and granulation tissue formation. All these observations were made on days 3, 7 and 14 post-operatively. Result: On the basis of findings of this study, it was concluded that autologous PRP is a better graft healing promoter in terms of self-limiting acute inflammation, fibroblast proliferation, granular tissue and early healing of graft as compared to homologous PRP.

The diminishing potential for development of further reservoirs, coupled with environmental awareness about the negative environmental impacts of reservoir construction and operation, has not only necessitated the need for improved operation of reservoirs through better planning, but has also created an additional demand on reservoirs in the form of instream flow requirements to preserve the ecological integrity of the rivers. The combination of these factors has lead to a considerable interest in both private and government water resources engineering practice in the use of mathematical models for optimisation of reservoir operations. The optimisation approaches which have been most commonly used for planning the operation of reservoirs are dynamic programming (DP), linear programming (LP) and non-linear programming. While all of these techniques are reasonably effective for optimisation of operation of single reservoirs, dynamic programs are by far the most frequently used partly because of the ease with which they can handle stochasticity of inflow regimes. However, while all the techniques, including dynamic programming techniques, are relatively easily applied to optimisation of single reservoirs, serious theoretical and computational issues arise when they are applied to the optimisation of the operations of multiple reservoir systems, particularly when stochastic issues related to inflow regimes or variation in demands are considered. For this reason, none of the above techniques have been able to be applied directly to the simultaneous optimisation of the operation of multiple reservoir systems. Instead, the optimisation processes have relied upon approximations such as decomposition of a system or joint simulation-optimisation approaches. The research reported in this thesis proposes a new approach to optimisation of the operation of reservoir systems, particularly multiple reservoir systems. This approach enables improved levels of consideration of the stochasticity of the inflow process while also significantly reducing the computational requirement and permits a more detailed and accurate representation of the system within the optimisation process. The approach is based on consideration of the stochasticity of inflows through the concept of Limiting State Probabilities. These Limiting State Probabilities rely on an assumption of stationarity of monthly transition probability matrices, an assumption which is also commonly used in stochastic reservoir operation models and define a probability distribution of inflows which, for each time period, are independent of the flows in the previous month, but which implicitly incorporate the time period to time period correlations normally captured by Markov processes. The Limiting State Probability vectors for each time period are obtained by a process of multiplication of the transition probability matrices associated with the inflows in that time period and the time period immediately preceding it. These Limiting State Probability vectors are the same as the marginal probabilities of inflows derived from steady state solutions in stochastic dynamic programs. The ability of Limiting State Probability vectors to remove the explicit temporal correlations is derived from the close relationship of Limiting State Probabilities to the long term steady state conditions of optimal reservoir operation. The elimination of temporal correlation also enables the spatial correlation between the inflows to reservoirs at different locations to be considered implicitly rather than explicitly. The spatial correlation is able to be eliminated from explicit consideration in the inflows to the model because the removal of the time period to time period correlation means that the results of a deterministic optimisation of reservoir using an inflow sequence generated by and conforming to the Limiting State Probability are independent of the actual order of inflows in that inflow series. This non-dependence of the results of the optimisation on the order of inflows enables the Limiting State Probability generated inflow sequences to be used as input to each reservoir in a multiple reservoir system with a diminished need to consider spatial correlation of inflows explicitly. The approach is validated first by application to the optimisation of the operation of a single reservoir wherein it is shown that the same results, i.e., optimal operating policies, are obtained when Limiting State Probabilities rather than traditional transition probability matrices are used in the recursive equations of the stochastic dynamic program. Optimal operation of the same single reservoir was then performed by the deterministic modelling technique network linear programming using inflow sequences generated by Limiting State Probabilities. The results obtained from the optimisation technique were similar to those obtained by stochastic dynamic programming with some of the differences being due to use of discrete variables in stochastic dynamic programming and continuous variables in the network linear program. Use of the Limiting State Probability concept was then extended to simultaneous optimisation, using network linear programming, of a multiple reservoir system comprising six reservoirs and seventeen demand centres, plus instream flow requirements. The deterministic inflow inputs, i.e., inflow sequences to each reservoir required by network linear programming were generated on the basis of Limiting State Probabilities relevant to each reservoir. The results of the application of the NLP technique using the inflows generated by Limiting State Probabilities showed the approach to be a computationally tractable and effective means to improved level of consideration of stochasticity of inflows in the optimisation of the operation of multiple reservoir systems.

Composites of Ga2O3 clusters and zeolite ZSM-5 were evaluated for the transformation of methanol to hydrocarbons. Comparison of the activity with ZSM-5 showed that the Ga2O3 clusters are responsible for the enhanced selectivity to aromatics via contact synergy, thus showing the importance of non framework gallium species for this reaction. TEM analysis of fresh and spent catalysts allowed the identification of the formation of carbonaceous products at the Ga2O3/zeolite interface region, and this interface is also the probable location of the catalyst active sites.

Catalysts comprising zeolite ZSM-5 impregnated with precious metals including Ag, Cu, Ni, Pd, Ir and Ru, have been tested for the methanol to hydrocarbons reaction in a continuous flow fixed bed reactor. Comparison with the activity of unmodified ZSM-5 showed that Ag, Cu and Ni enhanced the selectivity to C6–C11 aromatic products by a factor of two or higher. Moreover, Ag/ZSM-5 showed improved selectivity for the C6–C7 fraction of aromatic products. Ni/ZSM-5 was found to be selective to naphthalene, while Cu/ZSM-5 was selective for C9–C11 aromatic products. It was ascertained that all the impregnated metals were present as metal oxides in the starting materials. It is therefore proposed that the enhanced selectivity to aromatic products is due to the interaction of the acid sites of the zeolite with the basic sites of the metal oxide at the edge of the zeolite crystals, as well as the possible coordination of propene molecules formed during the reaction, that are likely to be the building blocks for the formation of aromatics.

The Perch is an AMS owned rooftop restaurant in the new student union building. The patio was originally only meant for summertime use, however AMS would like to extend patio use into the spring and autumn seasons. Conventional restaurant standard is to use propane heaters but due to the new LEED certification requirements, sustainability is the main priority. Therefore the purpose of our investigation was to discover or create a heating option for the Perch patio that would surpass propane heaters in sustainability. Evidently, the requirements also entailed that the solution had to be economically viable and socially acceptable. In other words, the outright cost of the solution as well as the maintenance and implementation must be outweighed by the return, and the solution must keep the public satisfied and comfortable. Solution constraints regarding implementation were given by Chiyi Tam during the Sustainability Project Workshop. Chiyi stated that the solution would require little to no structural implications as the solution would be implemented post construction and the SUB opening was already delayed as it is. This lead to another constraint, since structure integration would not be allowed, the solution must not obstruct the staff or customers, or become a tripping hazard. Chiyi also mentioned that since the patio setup would be dynamic, the solution was required to be either mobile, or unaffected by a change in the setup. To recap, the overall intent of our investigation was to discover, repurpose or create a heating solution for the patio. This solution must be financially feasible, socially acceptable as well as be non-structural, unobstructive and unaffected by any changes in the table layout. Our investigation consisted of research into three core solution categories: Mainstream heating appliances, alternative fuel sources and applications, and outside the box scenario analysis. During an APSC 261 assignment, we were requested to provide ten references, five of which were peer-reviewed. We took this as an opportunity to assemble a list of references on several different technologies and applications that could potentially be developed into a functional and sustainable solution. After the list was compiled, we assessed the options we had found and narrowed the list down to three unique technologies. The three technologies are the following: ● Photovoltaic panel charging stations (Solar Panels) ● Infrared heaters ● Kitchen heat exhaust recycling. Solar energy systems provide clean energy which can be stored for later use. Excess can also be sold to BC Hydro increasing profits. AMS LEED certification goals would also highly benefit from such a sustainable solution. Though local applications suggest that solar use has the potential to succeed, from a financial standpoint, the solution may not be viable though long term benefits may outweigh the cost. Infrared heaters provide quiet, fast, and efficient heat. They come in varying sizes which is valuable with limited structural implementation. Additionally, as infrared heaters can be powered with electricity, environmental impact is minimal. The financial analysis gave positive findings demonstrating a surprisingly low short term cost. Kitchen exhaust recycling is a recently developed technology that is slowly growing in popularity. The exhaust could be filtered with common air filter techniques such as active carbon filtering to provide clean hot air to patio occupants. This solution would be repurposing previously wasted energy and thusly would be providing a dual effect, lessening environmental impacts by the SUB as well as contributing to the LEED certification with an exponential factor. Implementation would be the greatest obstacle and though heat distribution effectiveness may also be a concern. After considering all the findings from above, we have decided that the best solution for the Perch would be a two part concurrent system. This system would consist of a ventilation duct that would repurpose wasted heat exhaust from the restaurants kitchen, filter any volatile organic compounds such as unwanted smells and/or chemicals and direct this heat onto patio occupants. This repurposing system would be working in tandem with the second part of the solution, infrared heaters. These heaters would ideally be mounted along the restaurants wall above the doors to avoid any hindrance. They are efficient, effective and can be powered by electrical plugins and would supplement the ventilation heater to ensure customer satisfaction. That being said, increased insulation on the ventilation ducts would ensure less heat loss making the primary system much more effective and thusly reducing energy costs from the infrared heaters. With the combination of the two heaters, customers would be sufficiently comfortable enough to enjoy their patio experience without any problems due to temperature. The platinum SEED accreditation would also benefit from the repurposing of wasted energy, and a sustainable SUB could be leveraged to promote AMS branding. A more detailed assessment of our investigation can be found below. Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report.”