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  • An exploration of socioeconomic variation in lifestyle factors and adiposity in the Ontario Food Survey through structural equation modeling
    An exploration of socioeconomic variation in lifestyle factors and adiposity in the Ontario Food Survey through structural equation modeling
    Title: An exploration of socioeconomic variation in lifestyle factors and adiposity in the Ontario Food Survey through structural equation models.Background: Socioeconomic indicators have been inversely associated with overweight and obesity, with stronger associations observed among women. The objective of the present secondary analysis was to examine the relationships among socioeconomic measures and adiposity for men and women participating in the Ontario Food Survey (OFS), and to explore lifestyle factors as potential mediators of these associations.Methods: The cross-sectional 1997/98 OFS collected anthropometric measurements, a food frequency questionnaire, data on socio-demographics (age, sex, income, and education) and physical activity from 620 women and 467 men, ages 18 to 75. Based on the 2003 Health Canada guidelines, waist circumference and BMI values were used to derive least risk, increased risk, and high risk adiposity groups. Structural equation modeling was conducted to examine increased risk and high risk adiposity in relation to education and income, with leisure time physical activity, fruit and vegetable intake, and smoking status included as potential mediators of these associations.Results: The probability of high risk adiposity was directly associated with education (β-0.19, p < 0.05) and income (β-0.22, p < 0.05) for women, but not for men. Fruit and vegetable intake was a marginally significant mediator of the relationship between education and high risk adiposity for women. Increased risk adiposity was not associated with income or education for men or women. Conclusion: The socioeconomic context of adiposity continues to differ greatly between men and women. For women only in the OFS, fruit and vegetable intake contributed to the inverse association between education and high risk adiposity; however, additional explanatory factors are yet to be determined., International Journal of Behavioral Nutrition and Physical Activity 2007, 4:8. doi:10.1186/1479- 5868-4-8
    An exploration of socioeconomic variation in lifestyle factors and adiposity in the Ontario Food Survey through structural equation modeling
    An exploration of socioeconomic variation in lifestyle factors and adiposity in the Ontario Food Survey through structural equation modeling
    Title An exploration of socioeconomic variation in lifestyle factors and adiposity in the Ontario Food Survey through structural equation models. Background Socioeconomic indicators have been inversely associated with overweight and obesity, with stronger associations observed among women. The objective of the present secondary analysis was to examine the relationships among socioeconomic measures and adiposity for men and women participating in the Ontario Food Survey (OFS), and to explore lifestyle factors as potential mediators of these associations. Methods The cross-sectional 1997/98 OFS collected anthropometric measurements, a food frequency questionnaire, data on socio-demographics (age, sex, income, and education) and physical activity from 620 women and 467 men, ages 18 to 75. Based on the 2003 Health Canada guidelines, waist circumference and BMI values were used to derive least risk, increased risk, and high risk adiposity groups. Structural equation modeling was conducted to examine increased risk and high risk adiposity in relation to education and income, with leisure time physical activity, fruit and vegetable intake, and smoking status included as potential mediators of these associations. Results The probability of high risk adiposity was directly associated with education (β-0.19, p < 0.05) and income (β-0.22, p < 0.05) for women, but not for men. Fruit and vegetable intake was a marginally significant mediator of the relationship between education and high risk adiposity for women. Increased risk adiposity was not associated with income or education for men or women. Conclusion The socioeconomic context of adiposity continues to differ greatly between men and women. For women only in the OFS, fruit and vegetable intake contributed to the inverse association between education and high risk adiposity; however, additional explanatory factors are yet to be determined., Ward, H., Tarasuk, V., Mendelson, R., & McKeown-Eyssen, G. (2007). An exploration of socioeconomic variation in lifestyle factors and adiposity in the ontario food survey through structural equation modeling. The International Journal of Behavioral Nutrition and Physical Activity, 4(1), 8-8. doi:10.1186/1479-5868-4-8 Export As... PrintEmail
    An exploration of user-generated wireless broadband infrastructures in digital cities
    An exploration of user-generated wireless broadband infrastructures in digital cities
    This paper examines the broadband connectivity options available in digital cities. It offers an overview of services provided by commercial operators, the public sector and by citizens themselves, arguing that shortcomings in existing fixed broadband and commercial mobile broadband services provide an opportunity for citizens to share their own wireless broadband connections. It explores Wi-Fi hotspot provider FON's approach to extending mobile broadband infrastructure by enabling shared connections within communities. The paper outlines some reasons why this specific user-generated approach to infrastructure provision has been unable to deliver highly robust broadband infrastructure, and discusses ways in which users and the public sector can be involved in developing new mobile infrastructures that will meet citizens' needs., Middleton, C. A., & Bryne, A. An Exploration of User-Generated Wireless Broadband Infrastructures in Digital Cities. Telematics & Infomatics, doi: 10.1016/j.tele.2010.08.003.
    An injectable glass polyalkenoate cement engineered for fracture fixation and stabilization
    An injectable glass polyalkenoate cement engineered for fracture fixation and stabilization
    Glass polyalkenoate cements (GPCs) have potential as bio-adhesives due to their ease of application, appropriate mechanical properties, radiopacity and chemical adhesion to bone. Aluminium (Al)-free GPCs have been discussed in the literature, but have proven difficult to balance injectability with mechanical integrity. For example, zinc-based, Al-free GPCs reported compressive strengths of 63 MPa, but set in under 2 min. Here, the authors design injectable GPCs (IGPCs) based on zinc-containing, Al-free silicate compositions containing GeO2, substituted for ZnO at 3% increments through the series. The setting reactions, injectability and mechanical properties of these GPCs were evaluated using both a hand-mix (h) technique, using a spatula for sample preparation and application and an injection (i) technique, using a 16-gauge needle, post mixing, for application. GPCs ability to act as a carrier for bovine serum albumin (BSA) was also evaluated. Germanium (Ge) and BSA containing IGPCs were produced and reported to have working times between 26 and 44 min and setting times between 37 and 55 min; the extended handling properties being as a result of less Ge. The incorporation of BSA into the cement had no effect on the handling and mechanical properties, but the latter were found to have increased compression strength with the addition of Ge from between 27 and 37 MPa after 30 days maturation. Keywords: fracture fixation; distal radius fracture; germanium oxide; polyacrylic acid; injectable glass polyalkenoate cements; bovine serum albumin, Khader, B., Peel, S., & Towler, M. (2017). An Injectable Glass Polyalkenoate Cement Engineered for Fracture Fixation and Stabilization. Journal of Functional Biomaterials, 8(3), 25., (This article belongs to the Special Issue Journal of Functional Biomaterials: Feature Papers 2016)
    An innovative dual-column system for heavy metallic ion sorption by natural zeolite
    An innovative dual-column system for heavy metallic ion sorption by natural zeolite
    This study investigates the design and performance of a novel sorption system containing natural zeolite. The apparatus consists of packed, fixed-bed, dual-columns with custom automated controls and sampling chambers, connected in series and stock fed by a metering pump at a controlled adjustable distribution. The purpose of the system is to remove heavy metallic ions predominately found in acid mine drainage, including lead (Pb2+), copper (Cu2+), iron (Fe3+), nickel (Ni2+) and zinc (Zn2+), combined in equal equivalence to form an acidified total 10 meq/L aqueous solution. Reported trends on the zeolite’s preference to these heavy metallic ions is established in the system breakthrough curve, as Pb2+ >> Fe3+ > Cu2+ > Zn2+ >> Ni2+. Within a 3-h contact period, Pb2+ is completely removed from both columns. Insufficient Ni2+ removal is achieved by either column with the promptest breakthrough attained, as zeolite demonstrates the least affinity towards it; however, a 48.97% removal is observed in the cumulative collection at the completion of the analysis period. The empty bed contact times for the first and second columns are 20 and 30 min, respectively; indicating a higher bed capacity at breakthrough and a lower usage rate of the zeolite mineral in the second column. This sorption system experimentally demonstrates the potential for industrial wastewater treatment technology development. Keywords: zeolite; sorption; packed fixed-bed columns; heavy metallic ions; automated sampling design, Ciosek, A. L., Luk, G. K. (2017). An Innovative Dual-Column System for Heavy Metallic Ion Sorption by Natural Zeolite. Applied Sciences, 7(8), 795., (This article belongs to the Special Issue Wastewater Treatment and Reuse Technologies)
    An interval-size illusion: The influence of timbre on the perceived size of melodic intervals
    An interval-size illusion: The influence of timbre on the perceived size of melodic intervals
    In four experiments, we investigated the influence of timbre on perceived interval size. In Experiment 1, musically untrained participants heard two successive tones and rated the pitch distance between them. Tones were separated by six or seven semitones and varied in timbre. Pitch changes were accompanied by a congruent timbre change (e.g., ascending interval involving a shift from a dull to a bright timbre), an incongruent timbre change (e.g., ascending interval involving a shift from a bright to a dull timbre), or no timbre change. Ratings of interval size were strongly influenced by timbre. The six-semitone interval with a congruent timbre change was perceived to be larger than the seven-semitone interval with an incongruent timbre change (interval illusion). Experiment 2 revealed similar effects for musically trained participants. In Experiment 3, participants compared the size of two intervals presented one after the other. Effects of timbre were again observed, including evidence of an interval illusion. Experiment 4 confirmed that timbre manipulations did not distort the perceived pitch of tones. Changes in timbre can expand or contract the perceived size of intervals without distorting individual pitches. We discuss processes underlying interval size perception and their relation to pitch perception mechanisms.
    Analysis of Stability-To-Chaos in the Dynamic Evolution of Network Traffic Flows under a Dual Updating Mechanism
    Analysis of Stability-To-Chaos in the Dynamic Evolution of Network Traffic Flows under a Dual Updating Mechanism
    This paper proposes a traffic-flow evolutionary model under a dual updating mechanism that describes the day-to-day (DTD) dynamics of traffic flow and travel cost. To illustrate the concept, a simple two-route network is considered. Based on the nonlinear dynamic theory, the equilibrium stability condition of the system is derived and the condition for the division between the bifurcation and chaotic states of the system is determined. The characteristics of the DTD dynamic evolution of network traffic flow are investigated using numerical experiments. The results show that the system is absolutely stable when the sensitivity of travelers toward the route cost parameter (θ) is equal to or less than 0.923. The bifurcation appears in the system when θ is larger than 0.923. For values of θ equal to or larger than 4.402, the chaos appears in the evolution of the system. The results also show that with the appearance of chaos, the boundary and interior crises begin to appear in the system when θ is larger than 6.773 and 10.403, respectively. The evolution of network traffic flow is always stable when the proportion of travelers who do not change the route is 84% or greater., Liu, S., Yan, H., Easa, S.M., Guo, L., Tang, Y. (2018). Analysis of Stability-To-Chaos in the Dynamic Evolution of Network Traffic Flows under a Dual Updating Mechanism. Sustainability, 10, 4182.
    Analysis of Ultrasound Backscatter from Ensembles of Cells and Isolated Nuclei
    Analysis of Ultrasound Backscatter from Ensembles of Cells and Isolated Nuclei
    Online version of a conference paper originally published as: Analysis of Ultrasound Backscatter from Ensembles of Cells and Isolated Nuclei, M.C. Kolios, G.J. Czarnota, M. Hussain, F. S. Foster, J.W. Hunt and M.D. Sherar (2001), In Proceedings of the 2001 IEEE International Ultrasonics Symposium Publisher URL: http://ieeexplore.ieee.org/xpls/abs_all.jsp?isnumber=21384&arnumber=991948&count=205&index=92
    Analysis of the Summon Service at Ryerson University
    Analysis of the Summon Service at Ryerson University
    Web Scale discovery services have become the holy grail for libraries to stay relevant to a generation that 'Googles' its way through research. But, do these discovery services improve learning? Does finding information faster equate to finding the most appropriate research? Our project is to analyse the learning outcomes of students at Ryerson University using Search Everything, powered by Summon, Poster Presented at CLA 2012 National Conference and Trade Show Ottawa, ON : Ottawa Convention Centre: May 30 - June 2, 2012
    Analytical and experimental solution for heat source located under skin:  chest tumor detection via IR camera
    Analytical and experimental solution for heat source located under skin: chest tumor detection via IR camera
    Infrared (IR) imaging could be used as both noninvasive and nonionizing technology. Utilizing IR camera, it is possible to measure skin temperature with the aim of finding any superficial tumors. Since tumors are highly vascular and usually have a higher temperature than the rest of the body, using thermograms, it is possible to assess various tumor parameters, such as depth, intensity, and radius. In this study, we have developed an analytical method to detect tumor parameters in both spherical and cubical tissues to represent female breast and male chest tissue. This includes development of analytical solution for solving inverse bio-heat problem as well as laboratory set up for further validation of the analytical achievements. The models were developed by solving Penne’s Bioheat equation for each tissue under certain conditions and two main assumptions: 1. The tumor was assumed as separate heat source; 2. The developed model does not change with time (steady state condition). Finally, the analytical findings were validated by utilizing a laboratory test set-up containing an IR camera, 1% Agar solution (tissue phantom), and a heater of variable powers. The models were set to test by adjusting the heater (0.9W) in various depth and imaging the tissue phantom. Comparing the analytically obtained results with the experimental results, it can be concluded that the method is able to detect superficial tumors of small size only by measuring the body surface temperature and ambient temperature.
    Analyzing the Usability of an Argumentation Map as a Participatory Spatial Decision Support Tool
    Analyzing the Usability of an Argumentation Map as a Participatory Spatial Decision Support Tool
    Argumentation Maps support participants in geographically referenced debates as they occur, for example, as part of urban planning processes. In a quasi-naturalistic case study, 11 student participants discussed planning issues on the University of Toronto downtown campus. The analysis of this case study focuses on general usability aspects of an Argumentation Map prototype, such as cost of entry, efficiency, interactivity, and connectivity. By applying usability analysis methods from the field of human-computer interaction, we evaluate the learnability, memorability, and user satisfaction with this tool’s functionality. Our findings indicate that the participants were generally satisfied, but we include specific suggestions for improving the functionality of Argumentation Maps, e.g., with respect to map navigation, display of discussion contributions, and online status of participants. On a more general level, this case study contributes to the methods spectrum of research into participatory spatial decision support systems as an example of user testing in a realistic decision-making context.
    Antiproliferative and Antioxidant Activities and Mycosporine-Like Amino Acid Profiles of Wild-Harvested and Cultivated Edible Canadian Marine Red Macroalgae
    Antiproliferative and Antioxidant Activities and Mycosporine-Like Amino Acid Profiles of Wild-Harvested and Cultivated Edible Canadian Marine Red Macroalgae
    Antiproliferative and antioxidant activities and mycosporine-like amino acid (MAA) profiles of methanol extracts from edible wild-harvested (Chondrus crispus, Mastocarpus stellatus, Palmaria palmata) and cultivated (C. crispus) marine red macroalgae were studied herein. Palythine, asterina-330, shinorine, palythinol, porphyra-334 and usujirene MAAs were identified in the macroalgal extracts by LC/MS/MS. Extract reducing activity rankings were (p < 0.001): wild P. palmata > cultivated C. crispus = wild M. stellatus > wild low-UV C. crispus > wild high-UV C. crispus; whereas oxygen radical absorbance capacities were (p < 0.001): wild M. stellatus > wild P. palmata > cultivated C. crispus > wild low-UV C. crispus > wild high-UV C. crispus. Extracts were antiproliferative against HeLa and U-937 cells (p < 0.001) from 0.125–4 mg/mL, 24 h. Wild P. palmata and cultivated C. crispus extracts increased (p < 0.001) HeLa caspase-3/7 activities and the proportion of cells arrested at Sub G1 (apoptotic) compared to wild-harvested C. crispus and M. stellatus extracts. HeLa cells incubated with wild P. palmata and cultivated C. crispus extracts also exhibited morphological changes characteristic of apoptosis (shrinkage, rounding). Thus, extracts rich in low-polarity usujirene and polar palythine and asterina-330 MAAs were antiproliferative as inducers of apoptosis in HeLa cells., Athukorala, Y., Trang, S., Kwok, C., & Yuan, Y. V. (2016). Antiproliferative and antioxidant activities and mycosporine-like amino acid profiles of wild-harvested and cultivated edible canadian marine red macroalgae. Molecules (Basel, Switzerland), 21(1), E119. doi:10.3390/molecules21010119, (This article belongs to the Special Issue Antioxidants—A Risk-Benefit Analysis for Health)