As the future of the world’s oil reserves becomes progressively more uncertain, it is becoming increasingly important that steps are taken to ensure that there are viable, attractive alternatives to travel by private motor vehicle. As with many of New Zealand’s major urban centres, Christchurch is still exceptionally reliant on private motor vehicles; although a significant proportion of the population indicate that they would like to cycle more, cycling is still an underutilised mode of transport. Following a series of fatal earthquakes that struck the city in 2010 and 2011, there has been the need to significantly redevelop much of the city’s horizontal infrastructure – subsequently providing the perfect platform for significant changes to be made to the road network. Many of the key planning frameworks governing the rebuild process have identified the need to improve Christchurch’s cycling facilities in order to boost cycling numbers and cyclist safety. The importance of considering future growth and travel patterns when planning for transport infrastructure has been highlighted extensively throughout literature. Accordingly, this study sought to identify areas where future cycle infrastructure development would be advantageous based on a number of population and employment projections, and likely future travel patterns throughout the city. Through the use of extensive GIS analysis, future population growth, employment and travel patterns for Christchurch city were examined in order to attain an understanding of where the current proposed major cycleways network could be improved, or extended. A range of data and network analysis were used to derive likely travel patterns throughout Christchurch in 2041. Trips were derived twice, once with a focus on simply finding the shortest route between each origin and destination, and then again with a focus on cyclist safety and areas where cyclists were unlikely to travel. It was found that although the proposed major cycleways network represents a significant step towards improving the cycling environment in Christchurch, there are areas of the city that will not be well serviced by the current proposed network in 2041. These include a number of key residential growth areas such as Halswell, Belfast and Prestons, along with a number of noteworthy key travel zones, particularly in areas close to the central city and key employment areas. Using network analysis, areas where improvements or extensions to the proposed network would be most beneficial were identified, and a number of potential extensions in a variety of areas throughout the city were added to the network of cycle ways. Although it has been found that filling small gaps in the network can have considerable positive outcomes, results from the prioritisation analysis suggested that initially in Christchurch demand is likely to be for more substantial extensions to the proposed major cycleways network.

Soil microbial communities can be characterized by community structure and function (community composition) across a spectrum of spatial scales, and variation in soil microbial composition has been associated with a number of environmental gradients. This study investigates the structure and function of soil microbial communities under mature, undisturbed forested sites across a range of regional climates in British Columbia and Alberta, and also examines the variation in community composition within sites. Phospholipid fatty acid analysis was used to investigate the structure of soil microbial communities and total soil microbial biomass at each site. Extra-cellular enzyme assays established the functional potential of the soil microbial community at each site. Multivariate analysis of the data showed that the soil microbial communities under different forest types did significantly separate along the regional climate gradient by both community structure and function, despite high local variation in the communities. Soil moisture content and soil organic matter concentration consistently exhibited the strongest relationship with microbial community characteristics, although the functional and structural responses to the external drivers were different. Microbial community function and structure also changed with soil depth but not with time of sampling. Microbial community function was related to the regional annual average precipitation gradient. Most of the locations exhibited unique microbial community functional profiles in their soil layers; however the enzyme activities in the samples from the driest (Ponderosa Pine) and wettest (Mountain Hemlock) locations were notably different from each other and from those of the other locations, especially in the organic layers. The moist maritime-influenced Coastal Western Hemlock (CWH) forest exhibited microbial community structural characteristics which were unique from those of the other forest locations. The higher abundance of bacteria relative to fungi in the CWH forest soils may be related to the significantly higher available nitrogen concentrations at this site.

Introduction: Several authors have demonstrated that, while cycling at a constant power output, EMG activity from the gastrocnemius increases systematically with increases in pedaling cadence, but that soleus EMG remains unchanged (Marsh & Martin 1995; Sanderson et al. 2006). The reason for this differential effect of cadence on the muscles of the triceps surae is unclear. Whatever factor(s) are responsible, it is assumed that, as they vary, the differential electromyographic response will vary accordingly. Decreasing the seat height has been shown to alter the kinematic characteristics of cycling (Too, 1990). The first objective of this study was to examine the effect of a decrease in seat height on the kinematics and muscle activation of the lower limb. The second objective was to investigate the effect of seat height on the relationship between cadence and triceps surae activation and, in doing so, to reveal possible factors mediating the response to changes in cadence. Methods: Participants pedaled a cycle ergometer at 200 Watts for five minutes at each of five cadences (50, 65, 80, 95, 110 rpm) and at each of two seat heights (100% and 90% trochanteric height). Kinematics of the lower limb were calculated from digitized video records of reflective markers placed on the skin over seven bony landmarks. EMG data were collected from eight lower-limb muscles. Results: The most notable findings were 1) that activation of the gastrocnemii was less in the low-seat condition and, contrary to what the findings of past research would suggest, was not associated with changes in muscle length; 2) that the medial and lateral gastrocnemii responded differently to changes in cadence at each seat height, suggesting that the functional roles of these muscles in cycling differ; 3) that several factors, including muscle length, muscle velocity, ankle angle and the direction of muscle action, were not responsible for the differential effect of cadence on activation of the soleus and gastrocnemius. Future research should investigate afferent feedback from proprioceptors in the knee joint and knee extensor muscles as possible factors mediating the effect.

This project defines the potential benefits of bicycling in major Canadian cities; determines the role of cycling within sustainable urban development; and suggests recommendations for maximizing the benefits of cycling in Canadian cities. The first phase of the project involved a review of academic literature and analysis of documents for four city case studies: Vancouver, British Columbia; Calgary, Alberta; Ottawa, Ontario; and Toronto, Ontario. Information was analyzed and themed to develop recommendations to maximize bicycling in these cities. The research suggests Vancouver and Ottawa are two of Canada’s leading cities in cycling innovation. Analysis of city documents found that most cities create in-depth cycling master plans which are difficult to successfully complete. Phase two of the project involved a 5400 kilometer bicycling tour in the summer of 2010 from Vancouver to Toronto. During the tour, each of the four cities were visited for a period of five to seven days and observations were made on cyclist infrastructure, safety, promotional and educational initiatives, planning, policy and law, and unique features. Photography and semi-structured interviews with urban planners, government officials, and cycling advocates were utilized to gain a unique perspective of the major cycling issues and innovations within each city. The research and observation indicated that a focus on creation of complete cycling networks; enforcement of cyclist rights; promotion and education; incentives and disincentives to the use of motorized vehicles; efficient use of funds for cycling infrastructure; the examination of municipal level cycling master plan policy; recognition of economic benefits of cycling; and knowledge and experience sharing between Canadian municipalities can increase overall rates of cycling within a city. / Thesis (Master, Environmental Studies) -- Queen's University, 2012-08-30 13:57:01.281

Chronic obstructive pulmonary disease (COPD) is characterized by an expiratory flow limitation, as well as an evident reduced exercise capacity compared to that of healthy age-matched individuals. Clearly, the expiratory flow limitation plays a significant role in this exercise intolerance; however, the extent of the contributions of other systemic factors remains unclear. More specifically, there is little data thus far on the role of blood flow delivery as a possible exercise limitation in COPD, especially in light of the potential interactions between cardiac output (Qc) and pulmonary hyperinflation. Thus, the purpose of this study was to compare the slope of the Qc versus oxygen uptake (VO 2) response through several submaximal cycling loads in patients with moderately severe COPD with that of age-matched healthy control subjects (CTRL). Also examined was the possibility that ventilatory constraints such as dynamic hyperinflation contribute to an abnormal Qc response. Cardiac output was measured using the CO2-rebreathing equilibrium technique during baseline conditions and cycling at 20, 40 and 65% of peak power in 17 COPD (Age: 64 +/- 8 yrs; FEV1/FVC: 37 +/- 11%; FEV1: 41 +/- 15% predicted) and 10 age-matched CTRL subjects. Inspiratory capacity (IC) was also measured for the determination of dynamic hyperinflation during the steady state exercise bouts. The results indicate that while the absolute Qc values are lower in COPD than in CTRL during moderately intense (65% peak power) cycling (11.30 +/- 2.38 vs. 15.63 +/- 2.15 L⋅min -1, p < 0.01), likely due to their lower exercise metabolic demand, the Qc/VO2 response to increasing levels of exercise intensity is normal or hyperdynamic in COPD. Indeed, the majority of patients with COPD exhibited Qc/VO2 slopes greater than 7.0, which may be indicative of a peripheral muscle bioenergetic disturbance that may drive the need for greater oxygen delivery, and thus result in an exaggerated ce

Background: As variable-geared, elliptical Rotor Q-rings may improve pedal dynamics by reducing the effect of the "dead spot" in the pedaling action and altering the mechanical leverage, use of these chain rings is currently gaining popularity among competitive amateur and professional cyclists. There are, however, no randomized, controlled, published studies examining the physiological effect of using Rotor Q-rings vs. standard circular chain rings. In addition, no previous studies comparing circular and noncircular chain rings have included analysis of the markers of exercise induced muscle damage. Aim: This work was designed to compare physiological response to an incremental cycling protocol when using Rotor Q-rings (QR) with an eccentricity ratio of 1.10 and 74° default setting, to that obtained when normal, circular chain rings (NR) are used. Methods: Twelve trained amateur cyclists (age: 40.67 ± 7.53 years) performed two incremental tests to exhaustion on their own bicycles in a controlled laboratory environment. The subjects were randomized to QR and NR trials which took place seven days apart, within a cross-over design. The type of chain ring attached to the cycle (QR vs. NR) was blinded from the participant. After an eight-minute warm-up at 130 W, the power output was increased by 30 W on the minute. During each trial, heart rate, VE, V02 were measured continuously and RPE and blood lactate concentration were measured during the last 15 seconds of each workload. Ventilatory and blood lactate turn- points were determined from serial VE and blood lactate concentrations. Serum lactate dehydrogenase (LDH) concentration was measured before and immediately after each trial. A numerical pain rating scale was used to assess post exercise leg muscle and knee joint soreness 24hr post trial. Results: There was no statistically significant difference (p > 0.05) in mean peak power output (380 ± 29.0 W vs. 385 ± 31.8 W), mean power (194.9 ± 12.7 W vs. 197.2 ± 16.7 W), mean distance covered (9.02 ± 1.29 km vs. 8.89 ± 1.84 km) during the QR and NR trials, respectively. There were no statistically significant differences between trials in submaximal and maximal V02, VE or RPE, and ventilatory or lactate turnpoints (p > 0.05). Knee pain and leg muscle soreness as well as and increment in serum LDH levels did also not differ significantly following the two trials (p > 0.05). The difference in peak blood lactate concentrations (12.62 mmol. £"' ± 2.15 on QR vs. 13.84 mmol. £"' ± 1.68 on NR), however, reached borderline significance (p = 0.055). Conclusion: Despite the popularity of non-circular chain rings and the apparent mechanical advantage derived from their use, the findings of this study were unable to provide support for significant physiological advantages when using Rotor Q-rings with an eccentricity ratio of 1.10 and 74° default setting, during an incremental cycling test to exhaustion. While the borderline significance of the lower mean maximal blood lactate concentration following the Q-ring trial requires confirmation in a larger study, the possible roles of training, higher eccentricity ratios and different orientations of the crank to the chain ring in eliciting a physiological advantage, require further investigation. / Thesis (M.Med.Sc.)-University of KwaZulu-Natal, 2008.

The goal of the present investigation was to evaluate the role of the pulmonary diffusion capacity (as measured by DLco) in relation to exercise-induced hypoxemia in elite athletes working at near maximal exercise intensities. Twenty-four elite cyclists were submitted to a direct measurement of VO$ sb2$ max on cycle ergometer which permitted classification into one of two groups. "Desaturaters" (N = 13) if oxyhemoglobin saturation (SaO$ sb2$%), as determined by finger oxymetry, fell below 91% or "non-desaturaters" if SaO$ sb2$% remained above 91%. Subsequent determinations of the transfer capacity for CO (DLco) were made using a 3 second breath-hold technique (Gould 2400/2450), at rest as well as at 60% and 90% of previously determined VO$ sb2$ max ($>$4.0 1/min). The results show an increase in DLco from rest to the first exercise intensity (desat: 41.7 $ pm$ 5.7 to 55.1 $ pm$ 4.7; non-desat: 41.1 $ pm$ 5.8 to 57.2 $ pm$ 6.9 mlsCO/mmHg/min) without much further increase to the maximal workload (desat: 61.0 $ pm$ 6.0; non-desat: 61.4 $ pm$ 9.5 mls CO/mmHg/min). No significant differences in DLco were found between the two groups at rest or either of the two exercise intensities. Significant differences between the desat and non-desat groups were found for FVC, post-exercise FEF$ sb{25-75 %}$, and VE/VO$ sb2$. / The present results are in agreement with previous reports showing arterial desaturation in 50% of highly-trained subjects when VO$ sb2$ max $>$4.0 1/min. The present investigation cannot clearly establish the role of DLco in this response. (Abstract shortened by UMI.)

Excess rural and urban nutrient inputs have led to downstream water quality degradation. Landowners in a small watershed in south central Manitoba, Canada have installed small dams as flood control mechanisms. Previous work has shown these dams and reservoirs are effective at decreasing total phosphorus (P) export, however questions of permanence, daily P fluctuation, and mechanisms influencing P retention still remain. Sediment nutrient dynamics can exert an important control on water quality on daily, monthly, and yearly timescales. To help better understand spatial and temporal patterns of P retention, P sorption assays were constructed (equilibrium P concentration or EPC0) and compared monthly measurements of EPC0 in small dammed reservoirs with their natural analog, stream pools. Dammed reservoirs and stream pools both showed a strong capacity to sorb P from the water column and as such, sediment processes represent a P sink across much of the catchment. In situ high frequency P sensors were deployed to assess short-term changes in P concentrations in four dammed reservoirs. Diel changes were only apparent later in the summer (August) but what drives these changes is unknown. Dam design to optimize nutrient retention should consider factors affecting P retention, including sediment geochemistry, but also residence time, and water chemistry as potential controls on P sorption. Diel sampling results suggest that water quality monitoring regimes that rely on singular grab samples should aim to sample in the mid-morning, especially later in the summer, so as to not over or underestimate P concentrations in water bodies.

No description available.

The purpose of this study was to quantify the EMG activity of selected lower limb muscles during cycling, and to define the relationship between pedal shaft width and muscular involvement. This study has particular significance to the female cyclist who by virtue of pelvic width may have a less efficient pedalling force, or an imbalance of applied muscular force. Variables analyzed were hip, knee, ankle range of motion (ROM), biceps femoris(BF), vastus lateralis(VL), rectus femoris(RF), and vastus medialis(VMO) muscle activity. Significant differences among three different pedal shaft widths were determined through use of repeated measures oneway ANOVA, Newman-Keuls post hoc test. The hip ROM, biceps femoris, and vastus medialis EKG activity results of the present study appeared to indicate that different pedal shaft widths had an effect on changes in the ROM and EMG activity. This study indicated that the hip ROM values increased with an increase in the pedal shaft width. In contary, an increase in pedal shaft width significantly decreased the muscle activity in the vastus medialis while two inch pedal shaft width significantly decreased the muscle activity in the biceps femoris. / School of Physical Education