Research

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
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)
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
Application of Scaling-Law and CFD Modeling to Hydrodynamics of Circulating Biomass Fluidized Bed Gasifier
Application of Scaling-Law and CFD Modeling to Hydrodynamics of Circulating Biomass Fluidized Bed Gasifier
Two modeling approaches, the scaling-law and CFD (Computational Fluid Dynamics) approaches, are presented in this paper. To save on experimental cost of the pilot plant, the scaling-law approach as a low-computational-cost method was adopted and a small scale column operating under ambient temperature and pressure was built. A series of laboratory tests and computer simulations were carried out to evaluate the hydrodynamic characteristics of a pilot fluidized-bed biomass gasifier. In the small scale column solids were fluidized. The pressure and other hydrodynamic properties were monitored for the validation of the scaling-law application. In addition to the scaling-law modeling method, the CFD approach was presented to simulate the gas-particle system in the small column. 2D CFD models were developed to simulate the hydrodynamic regime. The simulation results were validated with the experimental data from the small column. It was proved that the CFD model was able to accurately predict the hydrodynamics of the small column. The outcomes of this research present both the scaling law with the lower computational cost and the CFD modeling as a more robust method to suit various needs for the design of fluidized-bed gasifiers., Biglari, M., Liu, H., Elkamel, A., & Lohi, A. (2016). Application of scaling-law and CFD modeling to hydrodynamics of circulating biomass fluidized bed gasifier. Energies, 9(7), 504., (This article belongs to the Special Issue Energy from Forest Biomass)
Application of grammar-based codes for lossless compression of digital mammograms
Application of grammar-based codes for lossless compression of digital mammograms
A newly developed grammar-based lossless source coding theory and its implementation was proposed in 1999 and 2000, respectively, by Yang and Kieffer. The code first transforms the original data sequence into an irreducible context-free grammar, which is then compressed using arithmetic coding. In the study of grammarbased coding for mammography applications, we encountered two issues: processing time and limited number of single-character grammar G variables. For the first issue, we discover a feature that can simplify the matching subsequence search in the irreducible grammar transform process. Using this discovery, an extended grammar code technique is proposed and the processing time of the grammar code can be significantly reduced. For the second issue, we propose to use double-character symbols to increase the number of grammar variables. Under the condition that all the G variables have the same probability of being used, our analysis shows that the double- and single-character approaches have the same compression rates. By using the methods proposed, we show that the grammar code can outperform three other schemes: Lempel-Ziv-Welch (LZW), arithmetic, and Huffman on compression ratio, and has similar error tolerance capabilities as LZW coding undersimilar circumstances., J. Electron. Imaging, Vol. 15, 013021 (2006) http://dx.doi.org/10.1117/1.2178792