Research

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  • Vasculotide, an Angiopoietin-1 mimetic, reduces acute skin ionizing radiation damage in a preclinical mouse model
    Vasculotide, an Angiopoietin-1 mimetic, reduces acute skin ionizing radiation damage in a preclinical mouse model
    Background Most cancer patients are treated with radiotherapy, but the treatment can also damage the surrounding normal tissue. Acute skin damage from cancer radiotherapy diminishes patients’ quality of life, yet effective biological interventions for this damage are lacking. Protecting microvascular endothelial cells from irradiation-induced perturbations is emerging as a targeted damage-reduction strategy. Since Angiopoetin-1 signaling through the Tie2 receptor on endothelial cells opposes microvascular perturbations in other disease contexts, we used a preclinical Angiopoietin-1 mimic called Vasculotide to investigate its effect on skin radiation toxicity using a preclinical model. Methods Athymic mice were treated intraperitoneally with saline or Vasculotide and their flank skin was irradiated with a single large dose of ionizing radiation. Acute cutaneous damage and wound healing were evaluated by clinical skin grading, histology and immunostaining. Diffuse reflectance optical spectroscopy, myeloperoxidase-dependent bioluminescence imaging of neutrophils and a serum cytokine array were used to assess inflammation. Microvascular endothelial cell response to radiation was tested with in vitro clonogenic and Matrigel tubule formation assays. Tumour xenograft growth delay experiments were also performed. Appreciable differences between treatment groups were assessed mainly using parametric and non-parametric statistical tests comparing areas under curves, followed by post-hoc comparisons. Results In vivo, different schedules of Vasculotide treatment reduced the size of the irradiation-induced wound. Although skin damage scores remained similar on individual days, Vasculotide administered post irradiation resulted in less skin damage overall. Vasculotide alleviated irradiation-induced inflammation in the form of reduced levels of oxygenated hemoglobin, myeloperoxidase bioluminescence and chemokine MIP-2. Surprisingly, Vasculotide-treated animals also had higher microvascular endothelial cell density in wound granulation tissue. In vitro, Vasculotide enhanced the survival and function of irradiated endothelial cells. Conclusions Vasculotide administration reduces acute skin radiation damage in mice, and may do so by affecting several biological processes. This radiation protection approach may have clinical impact for cancer radiotherapy patients by reducing the severity of their acute skin radiation damage., Korpela, E., Yohan, D., Chin, L. C., Kim, A., Huang, X., Sade, S.. . Liu, S. K. (2014). Vasculotide, an angiopoietin-1 mimetic, reduces acute skin ionizing radiation damage in a preclinical mouse model. BMC Cancer, 14(1), 614-614. doi:10.1186/1471-2407-14-614
    Vehicle path planning for complete field coverage using genetic algorithms
    Vehicle path planning for complete field coverage using genetic algorithms
    In farming operations, one of the fundamental issues facing farmer is the cost of running the farm. If the equipment the farmer is using can be made more efficient, the cost of farming will be reduced. One way of making agricultural equipment more efficient is to develop automated or autonomous functions for the equipment. One of the fundamental tasks for autonomous equipment is to plan the path for the equipment to travel. This paper reports the research on the feasibility of creating an automated method of path planning for autonomous agricultural equipment. Genetic algorithms were chosen to plan the paths with a primary goal of creating an optimal path guiding the equipment to completely cover a field while avoiding all known obstacles. Two example fields were designed for evaluating the feasibility of this concept on simple problems. While simulation results verified the feasibility of this conceptual path planning method, they also indicated that further development would be required before the algorithm could actually be implemented on agricultural equipment for real-world field applications. Keywords: Automonous equipment, genetic algorithms, off-road vehicle, path planning, Ryerson, A. F., & Zhang, Q. (2007, July). Vehicle Path Planning for Complete Field Coverage Using Genetic Algorithms. Agricultural Engineering International: The CIGR Ejournal, IX.
    Vertical phosphorus migration in a biosolids-amended sandy loam soil in laboratory settings: concentrations in soils and leachates
    Vertical phosphorus migration in a biosolids-amended sandy loam soil in laboratory settings: concentrations in soils and leachates
    The impacts of biosolids land application on soil phosphorus and subsequent vertical migration to tile drainage were assessed in a laboratory setup. Soil, representing typical “nonresponse” Ontario soil as specified by Ontario Ministry of Agriculture, Food, and Rural Affairs (OMAFRA), was amended with anaerobically digested biosolids at a rate of 8Mgha−1 (dry weight). Over five months, these amended soil samples from two different depths were sequentially fractionated to determine various inorganic and organic phosphorus pools in order to evaluate phosphorus vertical migration within a soil profile. Soil leachate was analyzed for soluble reactive phosphorus.The results indicated that biosolids application did not significantly affect phosphorus concentrations in soil and did not cause phosphorus vertical migration. The concentrations of soluble reactive phosphorus also were not significantly affected by biosolids., Markunas, Y., Bostan, V., Laursen, A., Payne, M., & McCarthy, L. (2016). Vertical phosphorus migration in a biosolids-amended sandy loam soil in laboratory settings: Concentrations in soils and leachates. Applied and Environmental Soil Science, 2016 doi:10.1155/2016/3460939
    Vibration-based, nondestructive methodology for detecting multiple cracks in bending-torsion coupled laminated
composite beams
    Vibration-based, nondestructive methodology for detecting multiple cracks in bending-torsion coupled laminated composite beams
    Damage to composite structures occurs from impact, fatigue, or over stress and can be critical in the safe operation of wings or any structural member. This paper presents a method for detection of multiple cracks present in laminated composite bending-torsion coupled cantilevered beams using natural frequency data, a type of Nondestructive testing (NDT). This methodology relies on both experimentally collected natural frequencies and frequencies calculated using a mathematical model. Precise natural frequencies are calculated using a new dynamic finite cracked element (DFCE) formulated within and based on dynamic trigonometric shape functions. An algorithm is devised based on the Adam–Cawley criterion and extended to laminated composites with multiple cracks. This method has shown exceptional convergence on the size and location of cracks using a number of modes of free vibration with and without error in measured frequencies., Stephen R. Borneman and Seyed M. Hashemi, “Vibration-Based, Nondestructive Methodology for Detecting Multiple Cracks in Bending-Torsion Coupled Laminated Composite Beams,” Shock and Vibration, vol. 2018, Article ID 9628141, 10 pages, 2018. https://doi.org/10.1155/2018/9628141
    Virtual Tools for Assessing Human and Organisational Factors in Production System Design
    Virtual Tools for Assessing Human and Organisational Factors in Production System Design
    This paper describes two approaches for integrating human factors into discrete event simulations of production systems. In the first, biomechanical loading information was integrated with a simulation model in a car dismantling operation. In the second study, the productivity sensitivity of three systems with varying parallelisation was tested with respect to a) allowing operators to take breaks ‘as desired’, and b) having ‘reduced capacity’ operators at work. Both methods provided insight into design options that gave superior performance with improved ergonomics. Such ‘virtual ergonomics’ approaches can help establish boundary crossing discussions to support ergonomics application in early design stages., For a more in-depth look on this subject, please see: Kazmierczak, K., Neumann, W.P. and Winkel, J., 2007. A case study of serial-flow car disassembly: ergonomics, productivity, and potential system performance. Human Factors and Ergonomics in Manufacturing, 17(4): 331-351. DOI: 10.1002/hfm.20078 Neumann, W.P. and Medbo, P., 2009. Integrating human factors into discrete event simulations of parallel and serial flow strategies. Production Planning & Control, 20(1): 3-16. DOI: 10.1080/09537280802601444 Perez, J. and Neumann, W.P., 2010. The Use of Virtual Human Factors Tools in Industry – A Workshop Investigation, Ryerson University, Toronto.http://digitalcommons.ryerson.ca/ie/1/
    Virtual identity: applying narrative theory to online character development
    Virtual identity: applying narrative theory to online character development
    This paper will explore the realm of virtual identity within the context of the online virtual world, Second Life. The creation of virtual identities involves the complex process of constructing an online self-presentation. With the prevalence of online forums and virtual reality, ordinary people are crafting identities online and digressing from their actual identities in real life. In order to explain this phenomenon, I draw on narrative theory’s conceptualization of character in order to understand how people craft online identities., Yumansky, S. (2008, Spring). Virtual identity: applying narrative theory to online character development. Stream: Culture/Politics/Technology, 1(1). Retrieved from http://journals.sfu.ca/stream/index.php/stream/article/view/4/4
    Visible minority status and philanthropy
    Visible minority status and philanthropy
    Recognition of the multi-cultural nature of the Canadian population has led many companies across a wide array of business domains to consider ways of reaching beyond their traditional bases of support to target hitherto untapped ethnic communities. Market conditions within the voluntary sector are pushing nonprofits along this same path. Unfortunately, there is no systematic Canadian research on the attitudes, social norms, benefits sought, expectations, opportunities, experiences or behaviours of ethnic communities in the voluntary sector. This paper contributes to this gap by looking at philanthropic behaviour by visible minority status Keywords: CVSS, Centre for Voluntary Sector Studies, Working Paper Series,TRSM, Ted Rogers School of Management Citation:, Berger, I., & Azaria, J. (2004). Visible minority status and philanthropy (Working Paper Series Volume 2004 (1)). Toronto: Ted Rogers School of Management, Centre for Voluntary Sector Studies, Ryerson University.
    Visualization of Apoptotic Cells using Scanning Acoustic Microscopy and High Frequency Ultrasound
    Visualization of Apoptotic Cells using Scanning Acoustic Microscopy and High Frequency Ultrasound
    Online version of a conference paper originally published as: Visualization of Apoptotic Cells using Scanning Acoustic Microscopy and high frequency ultrasound, S. Brand*, G. J. Czarnota, E. C. Weiss, R. Lemor and M.C.Kolios, In Proceedings of the 2005 IEEE International Ultrasonics Symposium, Volume 2, Page(s):882 - 885 Publisher URL: http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=1602991
    Visualization of Lake Mead Surface Area Changes from 1972 to 2009
    Visualization of Lake Mead Surface Area Changes from 1972 to 2009
    For most of the last decade, the south-western portion of the United States has experienced a severe and enduring drought. This has caused serious concerns about water supply and management in the region. In this research, 30 orthorectified Landsat satellite images from the United States Geological Service (USGS) Earth Explorer archive were analyzed for the 1972 to 2009 period. The images encompassed Lake Mead (a major reservoir in this region) and were examined for changes in water surface area. Decadal lake area minimums/maximums were achieved in 1972/1979, 1981/1988, 1991/1998, and 2009/2000. The minimum lake area extent occurred in 2009 (356.4 km2), while the maximum occurred in 1998 (590.6 km2). Variable trends in water level and lake area were observed throughout the analysis period, however progressively lower values were observed since 2000. The Landsat derived lake areas show a very strong relationship with actual measured water levels at the Hoover Dam. Yearly water level variations at the dam vary minimally from the satellite derived estimates. A complete (yearly) record of satellite images may have helped to reduce the slight deviations in the time series., Forsythe, K. W., Schatz, B., Swales, S. J., Ferrato, L., & Atkinson, D. M. (2012). Visualization of lake mead surface area changes from 1972 to 2009. ISPRS International Journal of Geo-Information, 1(3), 108-119. doi:10.3390/ijgi1020108
    Visualizing Information in the Early Stages of Engineering Design
    Visualizing Information in the Early Stages of Engineering Design
    The early stages of engineering design are the most crucial for successful product development, yet they are not well supported with computer tools compared to other, downstream stages. This paper will discuss recent efforts by the authors to create visual representations of, and tools for, the non geometric, qualitative information typical in the early stages of engineering design. It appears evident that there is tremendous opportunity to improve the capacity of designers to think both critically and creatively through diagramming in early design, but the field is still embryonic and much work remains to be done., Salustri, F. A., Eng, N. L., & Weerasinghe, J. S. (2008). Visualizing Information in the Early Stages of Engineering Design. Computer-Aided Design and Applications, 5((1-4)), 1-18. doi:10.3722/cadaps.2008.xxx-yyy
    Wait times for publicly funded addiction and problem gambling treatment agencies in Ontario, Canada
    Wait times for publicly funded addiction and problem gambling treatment agencies in Ontario, Canada
    Background This study describes the definitions of wait times and intake processes used by drug and problem gambling treatment agencies in Ontario, Canada, as well as the various strategies employed to ameliorate client backlog. Methods An online survey was developed and distributed to 203 publicly-funded, provincial substance use and problem gambling treatment agencies from June to August, 2011. All aspects of the intake process were covered in the survey. Results Based on 139 responses, six different wait time periods were identified. Additional analyses were completed by type of service offered. Suggestions for effective interventions to shorten wait times and recommendations for future research are provided. Conclusion The results of this study highlight a need for standardized definitions of wait times across substance use and problem gambling treatment services., Pascoe, R. V., Rush, B., & Rotondi, N. K. (2013). Wait times for publicly funded addiction and problem gambling treatment agencies in ontario, canada. BMC Health Services Research, 13, 483. doi:10.1186/1472-6963-13-483