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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 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 Ultrasound Backscatter from Ensembles of Cells and Isolated Nuclei
    Analysis of Ultrasound Backscatter from Ensembles of Cells and Isolated Nuclei
    We have previously shown that the intensity of the ultrasound backscatter from cells ensembles undergoing apoptosis increases and shifts in their normalized power spectra are detected when compared to the backscatter from non-apoptotic cells. The etiology of these changes is unknown. During apoptosis many cellular changes occur, perhaps the most striking being the condensation and subsequent fragmentation of the cell nucleus. In this set of experiments have exposed either whole Acute Myeloid Leukemia (AML) cells or nuclei isolated from AML cells to different ionic strengths known to induce specific and reproducible cellular and nuclear changes. Ultrasound images and rf backscatter data were collected and analyzed at the different ionic strengths, and electron micrographs were made. Exposing cells to higher ionic strengths increased the ultrasound backscatter by 12 dB, but exposing the nuclei to the same experimental conditions decreased the backscatter by 23 dB. Furthermore, while the spectral slopes of the rf backscatter were similar for cells and nuclei at physiological saline, at increased concentrations the slope increased for the nuclei but decreased for the cells. The paper discusses the implications and significance of the findings. In conclusion, disruptions in cell and nuclear structure induced by exposure to strong ionic environments can greatly alter the ultrasound backscatter signal characteristics, 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
    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)
    Antitumor Effects of Combining Docetaxel (Taxotere) with the Antivascular Action of Ultrasound Stimulated Microbubbles
    Antitumor Effects of Combining Docetaxel (Taxotere) with the Antivascular Action of Ultrasound Stimulated Microbubbles
    Ultrasound stimulated microbubbles (USMB) are being investigated for their potential to promote the uptake of anticancer agents into tumor tissue by exploiting their ability to enhance microvascular permeability. At sufficiently high ultrasound transmit amplitudes it has also recently been shown that USMB treatments can, on their own, induce vascular damage, shutdown blood flow, and inhibit tumor growth. The objective of this study is to examine the antitumor effects of ‘antivascular’ USMB treatments in conjunction with chemotherapy, which differs from previous work which has sought to enhance drug uptake with USMBs by increasing vascular permeability. Conceptually this is a strategy similar to combining vascular disrupting agents with a chemotherapy, and we have selected the taxane docetaxel (Taxotere) for evaluating this approach as it has previously been shown to have potent antitumor effects when combined with small molecule vascular disrupting agents. Experiments were conducted on PC3 tumors implanted in athymic mice. USMB treatments were performed at a frequency of 1 MHz employing sequences of 50 ms bursts (0.00024 duty cycle) at 1.65 MPa. USMB treatments were administered on a weekly basis for 4 weeks with docetaxel (DTX) being given intravenously at a dose level of 5 mg/kg. The USMB treatments, either alone or in combination with DTX, induced an acute reduction in tumor perfusion which was accompanied at the 24 hour point by significantly enhanced necrosis and apoptosis. Longitudinal experiments showed a modest prolongation in survival but no significant growth inhibition occurred in DTX–only and USMB-only treatment groups relative to control tumors. The combined USMB-DTX treatment group produced tumor shrinkage in weeks 4–6, and significant growth inhibition and survival prolongation relative to the control (p<0.001), USMB-only (p<0.01) and DTX-only treatment groups (p<0.01). These results suggest the potential of enhancing the antitumor activity of docetaxel by combining it with antivascular USMB effects., Goertz DE, Todorova M, Mortazavi O, Agache V, Chen B, Karshafian R, et al. (2012) Antitumor Effects of Combining Docetaxel (Taxotere) with the Antivascular Action of Ultrasound Stimulated Microbubbles. PLoS ONE 7(12): e52307.
    Anxiety, depression, and self-management: a systematic review.
    Anxiety, depression, and self-management: a systematic review.
    The purpose of this article was to address the clinically relevant question: In the presence of anxiety and/or depression, do patients who have had heart surgery engage in self-management behaviours following hospital discharge? A systematic review of 16 studies that examined the psychological condition of patients who had coronary artery bypass graft (CABG) and/or valvular replacement surgery was conducted. Moderate to severe levels of anxiety and depression exist during the first month of home recovery and appear to have an effect on performance of self-management behaviors. As the influence of patients' psychological condition is continued to be examined, it is imperative for health care providers to manage increased rates of anxiety and/or depression following heart surgery. Music and relaxation therapy are presented as evidenced based recommendations for managing anxiety and depression in patients following heart surgery., Fredericks, S., Lapum, J., Lo, J. (2012). Anxiety, depression, and self-management: A systematic review. Clinical Nursing Research: An International Journal, 21(4), 411-429.
    Apoyo a la participación de padres en las escuelas primarias: Un estudio etnográfico sobre un grupo latinoamericano en Canadá
    Apoyo a la participación de padres en las escuelas primarias: Un estudio etnográfico sobre un grupo latinoamericano en Canadá
    Online version of an article originally published as: Bernhard, J.K., Freire, M., Pacini-Ketchabaw, V. (2000). Apoyo a la participación de padres en las escuelas primarias: Un estudio etnográfico de un grupo latino americano en Canadá. Educational Policy Analysis Archives, 8(52).
    Application Of Mathieu functions And The Point Matching Method To Elliptic Conductors
    Application Of Mathieu functions And The Point Matching Method To Elliptic Conductors
    Analysis of elliptic conductors, carrying a known total current, using the point matching method (PMM) in circular-cylinder coordinates [l] failed for the values of axes ratio b / a < 05, where a and b are the major and minor axes of the ellipse, respectively. This work shows that the use of elliptic-cylinder coordinates in conjunction with the point matching method overcomes this problem. This paper is a part of the work investigating the difficulties encountered in the point matching method, and is motivated by the fact that, despite its limitations, the method is still attractive as suggested by its use in recent papers [2]-141., Magnetics Conference, 1997. 1-4 Apr 1997. EP-04 - EP-04. http://dx.doi.org/10.1109/INTMAG.1997.597692