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BCIT Citations Collection

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CAD-CAM applications for spinal orthotics
In the summer of 1988, a joint study was done by the Prosthetics and Orthotics Department at the British Columbia Institute of Technology and the Medical Engineering Resource Unit (MERU) of the University of British Columbia. The study was undertaken to determine the feasibility of applying existing Computer Aided Design-Computer Aided Manufacture (CAD-CAM) techniques to the design and manufacture of spinal orthoses. The orthosis design selected was a TLSO for the treatment of a non-structural curve of the spine. The results of the study were very promising. This paper describes the study and discusses the results., Peer-reviewed article, Published.
A Canada-wide survey of chronic respiratory disease and spinal cord injury
With advances in acute care for individuals with spinal cord injury (SCI), chronic conditions are becoming a central focus.1–3 More specifically, impairments in respiratory function are one of the leading causes of morbidity and mortality among individuals with SCI,4 and have significant economic burden. Paresis or paralysis of the respiratory muscles can lead to respiratory insufficiency, which has a major impact on cough effectiveness and susceptibility to infection.5–7 Prior studies have typically focused on breathing mechanics and pneumonia in the acute stages of SCI, but there is a dearth of evidence regarding secondary chronic conditions, such as asthma and chronic obstructive pulmonary disease (COPD), among SCI populations. In the general population, risk factors for the development of asthma and COPD include genetic, sociodemographic, and environmental components.8,9 In addition, traffic pollution and occupational exposures, and indoor exposure to pollutants such as mold, increase susceptibility to both diseases. However, that SCI may be an independent risk factor for COPD and asthma (or vice versa) has not been previously examined. It thus remains unknown whether there is a higher prevalence of chronic respiratory diseases (after adjustment for potential confounders) in individuals with SCI. The current study addresses this knowledge gap by utilizing the national Canadian Community Health Survey, which comprises comprehensive, up-to-date, cross-sectional data. Our aim was to estimate the prevalence of chronic respiratory outcomes in the SCI population, to compare their odds with a non-SCI population, and to investigate this relationship after controlling for confounders., Peer-reviewed article, Published. Received September 18, 2014; Accepted December 09, 2014.
Carbonation in concrete infrastructure in the context of global climate change
A number of recent studies have identified and begun to quantify increased susceptibility of the infrastructure to climate change–induced carbonation of reinforced concrete. In this paper, the results of a study are presented which uses an updated empirical model to predict the diffusion coefficient of carbon dioxide (CO2) in concrete and thereafter, predict carbonation depths for a number of urban environments in the United States. Data from newer climate forecasts from the 5th Intergovernmental Panel on Climate Change assessment report are used to generate predictions for carbonation depths in four U.S. cities of varying geographic and climatic conditions (Los Angeles, Houston, Chicago, New York City). Results confirm that carbonation depths will increase in the future because of climate change. The magnitude of the increase is dependent on the climate-change scenario considered and the geographic location of the city. Whether or not the increases will require building code changes to increase concrete cover or improve concrete quality will be dependent on actual construction practices for the city in question., Peer-reviewed article, Published. Received: January 05, 2015; Accepted: July 30, 2015; Published online: October 28, 2015.
Carbonation in concrete infrastructure in the context of global climate change
There is nearly unanimous consensus amongst scientists that increasing greenhouse gas emissions, including CO2 generated by human activity, are effecting the Earth’s climate. Increasing atmospheric CO2 emissions will likely increase the rates of carbonation in reinforced concrete structures. However, there is a lack of reliable models to predict the depth of carbonation as a function of time. To address this deficiency, a numerical model involving simultaneous solution of the transient diffusion and reaction equations of CO2 and Ca(OH)2 was developed. The model successfully includes the effects of variations in various properties such as porosity, humidity, temperature, atmospheric CO2 concentrations and chemical reaction rates. The applicability of the model was confirmed after calibration using data from accelerated carbonation experiments, and the model is used to evaluate the possible effects of climate change by inputting various future climate scenarios in Part 2., Peer-reviewed article, Published.
Carbonation in concrete infrastructure in the context of global climate change
In Part1 of this paper, a carbonation model was developed and experimentally verified which was able to forecast carbonation depth of a concrete specimen considering varying ambient temperature, humidityand CO2 concentrations. Part 2 of the paper applies the carbonation diffusion/reaction model developed in Part 1 to predict the effects of global climate change on the carbonation of concrete. Climate scenarios were formulated and combined with the model for two major Canadian cities, Toronto and Vancouver. Results show that for undamaged and unstressed concrete, climate change will significantly affect carbonation progress. The model showed that for unloaded, non-pozzolanic concrete, ultimate carbonation depths in Toronto and Vancouver could be up to 45% higher. For in-service structures under load, the rates of deterioration are likely to be even faster. This is a cause for concern, and much further effort must be devoted to fully understand these phenomena., Peer-reviewed article, Published. Received 18 October 2011; Revised 21 April 2012; Accepted 24 April 2012; Available online 10 May 2012.
Carbonation in concrete infrastructure in the context of global climate change
There is nearly unanimous consensus amongst scientists that increasing greenhouse gas emissions, including CO2 generated by human activity, are affecting the Earth’s climate. Increasing atmospheric CO2 emissions will likely increase the rates of carbonation in reinforced concrete structures.In this paper, the serviceable life, from construction through to cracking due to carbonation induced corrosion of concrete infrastructure is considered in various cities throughout the world. It was concluded that global climate change will affect the progression and will result in much higher ultimate carbonation depths in the long term., Peer-reviewed article, Published. Received 23 May 2012; Revised 1 October 2012; Accepted 9 November 2012; Available online 25 December 2012.
Cardiovascular disease and spinal cord injury
Over the last decade, there have been marked changes in the trends of morbidity and mortality among individuals with spinal cord injury (SCI). With advances in acute care and in the management of septicemia, renal failure, and pneumonia, cardiovascular complications are now a leading cause of death in those with SCI.1 Moreover, several risk factors for cardiovascular disease (CVD) are amplified in individuals with SCI compared with able-bodied individuals, including physical inactivity, dyslipidemia, blood pressure irregularities, chronic inflammation, and abnormal glycemic control.2–22. While most of the literature with respect to CVD and SCI has shown a higher prevalence of risk factors for CVD,2–22 relatively few studies have examined the prevalence of CVD itself and corresponding risk estimates.23–26 None of these studies has provided direct comparisons of risk estimates for multiple CVD outcomes in the SCI population compared to a non-SCI population, with appropriate adjustment for confounding, in a large representative sample. It thus remains unknown whether there is excess risk of both heart disease and stroke (after adjustment for potential confounders) in individuals with SCI. The current study addresses this knowledge gap by utilizing the national Canadian Community Health Survey (CCHS), which is comprised of comprehensive, up-to-date, cross-sectional data. Our aim was to estimate the prevalence of heart disease and stroke outcomes in the SCI population, to compare their risk with a non-SCI population, and to investigate this relationship after controlling for confounders., Peer-reviewed article, Published. Received December 02, 2012 ; Accepted April 22, 2013.
Case studies on the use of information technology in the Canadian construction industry
A series of eleven case studies were gathered from across Canada in the summer of 2002. These case studies define an initial compendium of Best Practice in the use of information technology (IT) in Canada. The professionals interviewed included architects, engineers, general contractors, and owners. Many of them are at the cutting edge in their use of IT. The documentation of their pioneering use of IT can demonstrate how useful these technologies can be and what potential pitfalls are of concern. The case studies cover architecture, engineering, construction management, and specialized contractors. The following technologies were demonstrated: 3D CAD; custom Web sites; commercial Web portals; and in-house software development. No case was found that used wireless communication or standardized data formats such as IFCs or CIMSteel. The following issues were identified: the electronic distribution of documents is more efficient and cheaper; the short time-line and the tight budgets make it difficult to introduce new technologies on projects; the industry is locked in one CAD system and it is difficult to introduce new ones; it is costly to maintain trained CAD and IT personnel; and companies that lag behind reduce the potential benefits of IT. Still, the industry could achieve substantial benefits from the adoption of IT if it would be more widespread., Peer reviewed, Peer reviewed article, Submitted: August 2003 ; Revised: January 2004 ; Published: February 2004, Information technology, Technology use, Case studies, Architecture, Engineering and construction industry, Canada
A case study in using Standard 55 for a residential building prioritizing thermal comfort for homes
A 2015 ASHRAE news release corrected the assumption that thermal comfort research included only middle-aged men in suits working in offices.(1) Standard 55 is gender neutral and can be applied to most environments where people go-including into homes. ASHRAE stands behind this assertion through a 2014 interpretation, and includes the standard in its residential resources., Peer reviewed, Technical feature, Published., Standard 55, Thermal comfort
Characterizing the community use of an ultralight wheelchair with "on the fly" adjustable seating functions
An ultralight manual wheelchair that allows users to independently adjust rear seat height and backrest angle during normal everyday usage was recently commercialized. Prior research has been performed on wheelchair tilt, recline, and seat elevation use in the community, however no such research has been done on this new class of manual ultralight wheelchair with "on the fly" adjustments. The objective of this pilot study was to investigate and characterize the use of the two adjustable seating functions available on the Elevation™ ultralight dynamic wheelchair during its use in the community. Eight participants had data loggers installed onto their own wheelchair for seven days to measure rear seat height, backrest angle position, occupied sitting time, and distance traveled. Analysis of rear seat height and backrest adjustment data revealed considerable variability in the frequency of use and positions used by participants. There was a wide spread of mean daily rear seat heights among participants, from 34.1 cm to 46.7 cm. Two sub-groups of users were further identified: those who sat habitually at a single typical rear seat height, and those who varied their rear seat height more continuously. Findings also showed that participants used the rear seat height adjustment feature significantly more often than the backrest adjustment feature. This obvious contrast in feature use may indicate that new users of this class of wheelchair may benefit from specific training. While the small sample size and exploratory nature of this study limit the generalizability of our results, our findings offer a first look at how active wheelchairs users are using a new class of ultralight wheelchair with "on the fly" seating adjustments in their communities. Further studies are recommended to better understand the impact of dynamic seating and positioning on activity, participation and quality of life., Peer-reviewed article, Published. Received: April 28, 2016; Accepted: February 26, 2017; Published: March 9, 2017.
The chemical kinetics of shape determination in plants
Plants are integral to our lives, providing food, shelter and the air we breathe. The shapes that plants take are central to their functionality, tailoring each for its particular place in the ecosystem. Given the relatively large and static forms of plants, it may not be immediately apparent that chemical kinetics is involved in, for example, distinguishing the form of a spruce tree from that of a fern. But plants share the common feature that their shapes are continuously being generated, and this largely occurs in localized regions of cell division and expansion, such as the shoot and root apical meristems at either end of a plant’s main axis; these regions remain essentially embryonic throughout the life cycle. The final regular structure of a plant, such as the arrangement of leaves along the main stalk, may seem to follow an overall spatial template; but in reality the spatial patterning is occurring at relatively short range, and it is the temporal unfolding of this small scale patterning which generates the plant’s form. A key part of understanding plant morphogenesis, or shape generation, therefore, is to understand how the molecular determinants of cell type, cell division and cell expansion are localized to and patterned within the actively growing regions. At this scale, transport processes such as diffusion and convection are obvious components of localization, for moving molecules to the correct places; but the reaction kinetics for molecular creation, destruction and interaction are also critical to maintaining the molecular identity and the size regulation of the active regions., Book chapter, Published. Submission date: 04. October, 2011; Review date: 13. November, 2011; Published online: 29. February, 2012.
Climate change-induced carbonation of concrete infrastructure
There is a nearly unanimous consensus among scientists that increasing greenhouse gas emissions, primarily carbon dioxide generated by human activity, are effecting the Earth's climate. For many key parameters, the climate system is already moving beyond the patterns of natural variability within which our societies and economies have developed and thrived. These parameters include global mean surface temperature, sea-level, ocean and ice sheet dynamics, and extreme climatic events. There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts. One overlooked area of research is the impact of climate change on concrete infrastructure. Concrete structures form an essential part of the world. Climate change could potentially affect the durability of concrete infrastructure. In this paper, the findings of a study at the University of British Columbia which demonstrate a long-term risk to the durability of steel-reinforced concrete structures in some parts of the world via accelerated carbonation-induced corrosion are presented. Research demonstrates that service lifespans of structures will be affected in the long term, with the need for earlier repairs unless the adverse effects of climate change are taken into account at the time of design., Peer-reviewed article, Published.

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