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During take-off, the aerodynamic performance of a transonic engine intake is dominated by the flow-field over the nacelle lower lip, around which the flow might accelerate to supersonic speeds. A shock wave might appear and impinge on the incoming boundary layer. Flow separation may result from this interaction, leading to severe flow distortion. In order to maximise fuel efficiency by reducing aerodynamic drag, slimmer nacelle designs are currently being pursued by manufacturers. Understanding the impact of design choices on the development of shock-wave boundary layer interactions (SBLI) is crucial, as these phenomena have a severe effect on the stability of the flow inside the nacelle. The available literature is rather scarce and unable to assess the nature and severity of SBLIs, which remain to be addressed in the context of nacelles at incidence. To address this shortcoming, a novel experimental rig has been designed exclusively to assess the detrimental effects resulting from shock-induced separation for a number of intake lip shapes and inflow conditions. For the reference intake shape, the flow field around the lower lip during on-design take-off conditions was found to be relatively benign, with minimal shock-induced separation. As incidence is increased by 2◦, from the reference incidence of 23◦, this separation gets noticeably larger and unsteadiness develops. The downstream boundary layer is more distorted and reflects the losses across the interaction. This is exacerbated at even higher incidence. Increasing the mass flow rate over the lip up to 15% of the initial value had only minor effects on performance. The parametric investigation revealed a significant effect of lip shape on the position and severity of the SBLI. In particular, a slimmer nacelle performed poorly, favouring shock development very close to the lip nose and promoting large scale separation as the incidence increases. From correlation studies based on the parametric investigation, it appears that the extent of shock-induced separation is the main factor affecting the aerodynamic performance. Somewhat surprisingly, this was found to be independent of shock strength but potentially related to the severity of the diffusion downstream of the shock. Alongside delaying flow reattachment, this diffusion is also likely to have a direct detrimental effect on the boundary layer development close to the engine fan.

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Pulses are nutrient dense foods that possess many beneficial effects. The purpose of this project was to examine the prevalence and effect of pulse consumption on nutrient intake in Canadian adults (≥ 19 y). Analysis was performed on data (N = 20,156) from the 2004 Canadian Community Health Survey (Cycle 2.2). Respondents were divided into groups based on pulse consumption and levels of intake and the association between nutrient intakes and pulse consumption was examined. Analysis revealed that thirteen percent of Canadians consumed pulses on any given day, and individuals with higher pulse intakes had higher intakes of macronutrients as well as enhanced micronutrient intake. Although pulses are generally low in sodium, its intake also was higher in pulse consumers. These data indicate that pulse consumption supports dietary advice that pulses be included in healthful diets. Further studies will be necessary so that dietary advice to increase consumption of pulses will maximize their nutritional benefits.

Pulses are nutrient dense foods that possess many beneficial effects. The purpose of this project was to examine the prevalence and effect of pulse consumption on nutrient intake in Canadian adults (≥ 19 y). Analysis was performed on data (N = 20,156) from the 2004 Canadian Community Health Survey (Cycle 2.2). Respondents were divided into groups based on pulse consumption and levels of intake and the association between nutrient intakes and pulse consumption was examined. Analysis revealed that thirteen percent of Canadians consumed pulses on any given day, and individuals with higher pulse intakes had higher intakes of macronutrients as well as enhanced micronutrient intake. Although pulses are generally low in sodium, its intake also was higher in pulse consumers. These data indicate that pulse consumption supports dietary advice that pulses be included in healthful diets. Further studies will be necessary so that dietary advice to increase consumption of pulses will maximize their nutritional benefits.

Thesis (Ocean E)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1979. / Supervised by Loren R. Haury, Douglas E. Kenyon and Henri O. Berteaux. Includes bibliographical references (leaves 134-137).

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In Australia, and other Western countries, there are marked socioeconomic inequalities in mortality from chronic, diet-related diseases. Research in these countries has shown that adults from low socioeconomic backgrounds experience greater morbidity and mortality from these conditions compared to their higher-status counterparts. In recent decades, much research has focused on factors that may contribute to these inequalities. Dietary intakes are thought to account for a large proportion of the socioeconomic variability in health, and there is some evidence suggesting that the psychosocial foundations laid down in adolescence are important influences on these dietary intakes. In Australia, however, existing research examining socioeconomic differences in dietary intakes is limited. Most previous research has looked at dietary intakes in adulthood, and have not considered examining for socioeconomic differences in adolescence. Furthermore, not much is known about the health and nutrition-related beliefs, attitudes and perceptions of adolescents that may contribute to socioeconomic differences in dietary intakes. This study examined these issues by analysing for socioeconomic differences in food and nutrient intakes among both adolescents and adults. It also investigated some health and nutrition-related beliefs, attitudes and perceptions of adolescents from different socioeconomic backgrounds. Data from a national cross-sectional survey, the 1995 Australian National Nutrition Survey, were analysed to determine socioeconomic differences in food and nutrient intakes. Qualitative interviews were undertaken with adolescents to investigate their health and nutrition-related beliefs, attitudes and perceptions. The results show that compared to adults, there is less socioeconomic inequality in food and nutrient intakes among adolescents. Intakes of some anti-oxidant vitamins and folate were directly related with socioeconomic position among adults. Adults from low socioeconomic backgrounds were less likely to consume fruits or vegetables. They consumed a lower variety of fruits and vegetables and were less likely to choose fruits and vegetables high in vitamin A, folate and vitamin C. The results showed that these differences may be due to adults from low socioeconomic backgrounds being less likely to want to increase their fruit and vegetable intakes, and perceiving price and storage as barriers to doing so. There were a small number of socioeconomic differences in adolescents' beliefs, attitudes and perceptions about nutrition and health that may contribute to dietary intake inequalities in adulthood. Adolescents from lower socioeconomic backgrounds were less likely to see health as being important for achieving goals, and identified nutrients and sleep as influencing their health less frequently. These adolescents also referred to dietary recommendations, nutrient intakes, dairy foods and avoiding school canteen foods less frequently when describing a healthy diet. A number of recommendations about the design and targeting of nutrition-promotion campaigns and interventions are discussed, as well as future directions for research on socioeconomic differences in dietary intakes.

Aero-engine intakes play a critical role in the performance of modern high-bypass turbofan engines. It is their function to provide uniformly distributed, steady air flow to the engine fan face under a variety of flow conditions. However, during situations of high incidence, high curvature of the intake lip can accelerate flow to supersonic speeds, terminating with a shock wave. This produces undesirable shock wave boundary layer interactions (SWBLIs). Reynolds-Averaged Navier Stokes (RANS) turbulence models have been shown to be insensitive to the effects of boundary layer relaminarisation present in these highly-accelerated flows. Further, downstream of the SWBLI, RANS methods fail to capture the distorted flow that propagates towards the engine fan face. The present work describes simulations of a novel experimental intake rig model that replicates the key physics found in a real intake- namely acceleration, shock and SWBLI. The model is a simple geometric configuration resembling a lower intake lip at incidence. Simulations are carried out at two angles of attack, $\alpha=23^{\circ}$ and $\alpha=25^{\circ}$, with the more aggressive $\alpha=25^{\circ}$ possessing a high degree of shock oscillation. RANS, Large Eddy Simulations (LES) and hybrid RANS-LES are carried out in this work. Modifications to the one-equation Spalart-Allmaras (SA) RANS turbulence model are proposed to account for the effects of re-laminarisation and curvature. The simulation methods are validated against two canonical test cases. The first is a subsonic hump model where RANS modifications give a noticeable improvement in surface pressure predictions, even for this mild acceleration case. However, RANS is shown to over-predict the separation size. LES performs much better here, as long as the Smagorinsky-Lilly SGS model is not used. The $\sigma$-SGS model is found to perform best, and is used to run a hybrid RANS-LES that predicts a separation bubble size within $4\%$ of LES. The second canonical test case is a transonic hump that features a normal shockwave and SWBLI. RANS performs well here, predicting shock location, surface pressure and separation with good agreement with experimental measurements. Hybrid RANS-LES also performs well, but predicts a shock downstream of that measured by experiment. The use of an improved shock sensor here is able to maintain solution accuracy. Simulations of the intake rig are then run. RANS modifications provide a significant improvement in prediction of the shock location and lip surface pressure compared to the standard SA model. However, RANS models fail to reproduce the post shock interaction flow well, giving incorrect shape of the flow distortion. Further, RANS is inherently unable to capture the unsteady shock oscillations and related flow features. LES and hybrid RANS-LES predict the shock location and SWBLI well, with the downstream flow distortion also in very good agreement with experimental measurements. LES and hybrid RANS-LES are able to reproduce the time averaged smearing of the shock which RANS cannot. However, shock oscillations in the $\alpha=25^{\circ}$ case present a particular challenge for costly LES, requiring long simulation time to obtain time averaged flow statistics. Hybrid RANS-LES offers a significant saving in computational expense, costing approximately $20\%$ of LES. The work proposes recommendations for simulation strategy for intakes at incidence based on computational cost and performance of simulation methods.