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Ventilation systems are used to exhaust stale air and bring fresh air into sealed buildings. To maintain a comfortable indoor environment, this incoming air must be heated or cooled, which consumes energy. Consequently, membrane-based plate-type energy recovery ventilators are a component used in many energy-efficient ventilation systems. In these air-to-air energy recovery ventilator exchangers, incoming and outgoing air streams are passed over opposing sides of a membrane through which heat and moisture are transferred. This decreases the energy use of buildings by using the exhaust air to heat/cool and humidify/dehumidify the incoming air depending on the season. Ideally, membranes for these devices should have high water vapor permeation rates and be selective for water vapor over the transport of other gases and volatile organic compounds, including formaldehyde, odors, and contaminants, that may be present in the outgoing indoor air stream. Current certification and standards for contaminant crossov...

Untreated transgender men face serious negative health care outcomes. Effective medical, surgical, and mental health treatment ameliorates these risks. Although the research is not as robust as would be ideal, hormone treatment is effective and generally well tolerated with few serious medical risks. Surgeries carry serious risks; but for most transgender men, the benefits outweigh the risks. This review describes current evidence-based medical treatments for transgender men and provides an overview of surgical therapy to enable practitioners to discuss these options with their transgender male patients.

Membranes with high water vapour permeance and selectivity find many end uses including protective clothing, dehydration, and humidification. One application for water vapour transport membranes is in energy recovery ventilators (ERVs) for buildings. These devices improve building energy efficiency by transporting heat and moisture between incoming and outgoing air streams in building ventilation systems, effectively ‘recycling’ the energy used to condition the indoor air. Membranes for these devices must have high vapour permeance, and selectivity for water vapour over other gases and contaminants that may be present in the exhaust indoor air. Due to the high rates of water vapour transport required in these gas to gas devices, boundary layer and internal resistances within the membrane contribute significantly to performance. Commercially available membranes suffer from high water vapour transport resistance in the microporous substrate support layer. In this study we report the fabrication of novel impregnated electrospun nanofibrous membranes (IENM) for water vapour transport applications. Electrospun nanofibre layers are impregnated with a polyether–polyurethane solution and cured to create continuous thin impregnated fibre loaded film layers which are bound to a non-woven support layer. These membranes have high water vapour permeance and selectivity while eliminating the requirement for a microporous support layer which has high vapour transport resistance. Here we report initial studies on how controllable factors in the membrane fabrication (namely fibre loading and impregnated solution polymer solids concentration) affect structural and permeation properties of IENMs created. Membranes with adequate permeance and selectivity are demonstrated and direction for optimization is identified. We find that the nanofibre loading has a significant impact on water vapour permeability as the membrane thickness decreases. Future work will study how modifications to the geometric and structural properties of the fibres affect the membrane performance.

Naphthenic acids (NA) are components of most petroleum, including those found in the Athabasca oil sands and in some systems are considered to be persistent compounds. Their presence in the environment can pose significant problems since freshly released NAs are toxic to aquatic organisms. In this investigation gamma irradiation (GI) was used to reduce the toxicity and concentration of NAs in oil sand tailings and assess the impact on biogeochemical processes. GI reduced NA concentration by up to 97% in Oil Sands Process Water (OSPW) and 85% in fluid fine tailings (FFT). Dissolved oxygen flux was stimulated directly in the GI-treated FFT in both fresh and aged sources, while increases in hydrogen sulfide flux was restricted to the fresh FFT source material. Acute toxicity to Vibrio fischeri was immediately reduced following GI treatment of fresh OSPW. GI treatment followed by 28-day incubation reduced toxicity of aged OSPW to Vibrio fischeri.

Includes bibliographical references, Defensible space aims to provide residents with the power to control their residential environment, so that they will defend it against any threat. While the literature on defensible space is prolific, and while its principles are still being adapted for different contexts across the world, critiques of defensible space indicate that its validity for different contexts is questionable and necessitates further exploration. This paper explores how the implementation of defensible space principles in the Violence Prevention through Urban Upgrading (VPUU) safe node area of Harare, Khayelitsha has reduced crime rates and anti-social behaviour. Furthermore, it also aims to provide planners with knowledge regarding VPUU's prescription to defensible space principles. The research was conducted primarily through the use of the case study method, and a critical discourse analysis of VPUU's urban design principles. Harare's crime statistics were analysed through the use of mixed methods, in order to gain an understanding of how crime has been affected in the area. Interviews with locals from Harare provided insight on how residents perceived safety in their area after VPUU's intervention. Observations were also made in order to understand how the intervention area functions and how people use it. Cognitive mapping was done with primary school children to ascertain their perceptions of safety in Harare. The research findings revealed that the implementation of defensible space principles in Harare has improved the quality of public space, but it has not reduced crime rates or anti-social behaviour. Moreover, the main finding revealed that crime was not solely a result of design flaws, but rather as a result of the social conditions in the neighbourhood. As a result, the main recommendation was that crime prevention strategies should not focus solely on design but should address the social conditions present. The researcher argues that the implementation of defensible space principles should be context-driven, because what works in one context will not necessarily work in another.

The mammalian photoreceptor is a dynamic polarized cell, in which protein transport and translocation are continuously taking place. The ability of these cells to accurately and efficiently localize protein components is essential for survival and proper functioning. Post-biosynthesis protein transport from IS to OS and translocation of transducin from OS to IS and back again, in response to light and dark, respectively, test the transport systems in these cells. Additionally, localization of membrane-associated proteins offers a challenge, as lipidated proteins must move freely within the hydrophilic intracellular environment until reaching a destination membrane. As a result, photoreceptors are an ideal model for studying intracellular membrane-associated protein trafficking. Chapter 1 reviews photoreceptor structure and describes the need for accurate and efficient transport mechanisms in these cells. Eukaryotic prenylation and acylation are examined providing context for discussing the biosynthesis, transport, and light-induced translocation of transducin. Lastly, UNC119, which interacts with and is critical in mediating transducin's translocation, is reviewed. Chapter 2 focuses on the biochemical and structural characterization of the UNC119-transducin-α interaction. The co-crystal structure of UNC119-Lauroyl- GAGASAEEKH at 2.0Å resolution offers definitive evidence for this interaction. Wildtype and Unc119-/- mouse models in conjunction with C. elegans unc-119 mutants provide in vivo evidence that UNC119 is required for G protein trafficking in sensory neurons. These data provide the first detailed description of a specific UNC119 function offering insight into the mechanism underlying transducin light-induced translocation. Chapter 3 touches on the generation of an UNC119-Tα-GMPPNP complex, but moves away from light-induced translocation and describes the role PrBP/δ plays in postbiosynthesis transport of PDE6. A general review of PrBP/δ and PDE6 offers a basic foundation for understanding how these two proteins interact and what role this interaction plays. While efforts focused on generating protein crystals of a PrBP/δ-PDE6 complex were unsuccessful, collaboration with Ted Wensel's group yielded a cryo-EM reconstruction of the complex and its features and implications are discussed. Chapter 4 concludes this work with discussions of the aforementioned findings and future directions that might prove useful in further understanding the role UNC119 plays in G protein trafficking and how the PDE6-PrBP/δ complex assembles.

Plastic optical fiber (POF) for use in automotive applications is not a new concept and has been used in some vehicles for infotainment media distribution within the Media Oriented Systems Transport protocol. However, the use of POF for the control network's physical layer is a concept that has not been implemented in automotive applications. Many aspects of a vehicle can be improved by implementing POF as the physical backbone for the control network. Currently, the Controller Area Network (CAN) is used as the primary backbone control network protocol for most automobiles as it is inexpensive and reliable. However, CAN is limited to 500 kbps in most vehicles and is easily accessible. Ethernet may provide the improvements of speed and security needed in today's feature rich and connected vehicles. The feasibility of implementing Ethernet over POF as the control network for automotive applications is the topic of this research investigation.