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In this thesis, a methodology is presented to automate the labelling, event detection, segmentation, tracking, and parameter extraction of IMU gait data for sensors placed on the feet and shanks. The algorithms presented were tested using IMU data from three different styles of gait, normal gait, antalgic gait, and limited mobility gait. The algorithms developed were found effective for all of the simulated gait styles without mislabelling or detecting erroneous gait segments. The resultant gait trajectories and parameters were analyzed and were found to accurately depict the differences between each of the different styles of gait. The methodology presented can be used for the rapid and accurate processing of gait data for multiple styles of gait. This quantification of gait data can enable the collection of IMU gait data on a larger scale. This provides an accessible, low-cost option for out-of-laboratory gait data collection.

The Loess Plateau suffers from severe soil erosion that leads to a series of ecological and economic problems such as reduced land productivity, exacerbated rural poverty, decreased biodiversity and sedimentation of the riverbed in the lower reaches of the Yellow River. Soil erosion models are commonly used on the Loess Plateau to help target sustainable land management strategies to control soil erosion. In this study, we compared eleven soil erosion models that were previously used on the Loess Plateau. We studied their prediction accuracy, process representation, data and calibration requirements, and potential application in scenario studies. The selected models consisted of a broad range of model types, structures and scales. The comparison showed that process-based and empirical models did not necessarily yield more accurate results over one another for the Loess Plateau. Among the process-based models, Si’ model, WEPP and MMF had the highest prediction accuracy. However, some of the selected models were tested with total sediment load while others were tested with suspended sediment load (i.e. bedload is not included), which is subject to several drawbacks. Research questions that each of the models can address on the Loess Plateau were suggested. Further improvement of soil erosion models for the Loess Plateau should concentrate on enhancing the quality of data for model implementation and testing, incorporating key processes into process-based models according to their aims and scales, comparing models that address the same research questions, and implementing internal and spatial model testing.

Peatlands are important terrestrial carbon stores particularly in the Northern Hemisphere. Many peatlands, such as those in the British Isles, Sweden and Canada, have undergone increased erosion, resulting in degraded water quality and depleted soil carbon stocks. It is unclear how climate change may impact future peat erosion. Here we use a physically-based erosion model (PESERA-PEAT), driven by seven different global climate models (GCMs), to predict fluvial blanket peat erosion in the Northern Hemisphere under 21st-century climate change. After an initial decline, total hemispheric blanket peat erosion rates are found to increase during 2070-2099 (2080s) compared with the baseline period (1961-1990) for most of the GCMs. Regional erosion variability is high with changes to baseline ranging between -1.27 and +21.63 t ha-1 yr-1 in the 2080s. These responses are driven by effects of temperature (generally more dominant) and precipitation change on weathering processes. Low latitude and warm blanket peatlands are at most risk to fluvial erosion under 21st-century climate change.

Many peatlands across the world suffer from degradation. Blanket peatlands are found mainly in high latitude oceanic areas and subpolar islands. Exacerbated erosion of blanket peatlands is common particularly where they have been disturbed by human influence or where climate has become more marginal for their functioning. A recently developed fluvial blanket peat erosion model, PESERA-PEAT was applied across 845 km2 of blanket peatlands in the North Pennines of northern England. The aim was to evaluate the spatial and temporal variability of erosion rates under climate change and land management scenarios. Climate change data to the end of the 21st Century, derived from UKCP09 median emission projections aligned to the UK Met Office’s historical meteorological dataset, were downscaled to 100 m cells. Land management scenarios were developed which included intensified and extensified grazing, artificial drainage and prescribed burning. The modelling results showed that under current management, 21st Century climate change would slightly increase the overall fluvial erosion rates for the study region from the climatic baseline (2.2 t ha-1 yr-1) to the 2080s (2.3 t ha-1 yr-1 ). However, the predicted response to climate change was spatially very variable. Predicted erosion rates decreased at locations that are currently wet and cold while they increased in some warmer and drier locations by more than 50%. Summer desiccation was found to become more important for the study region under climate change. Thus, predicted autumn sediment yields became the biggest component of the annual budget by the 2080s. Less intensive management was shown to reduce blanket peat erosion but potentially enhance wildfire severity. The results demonstrated that land management change will be useful in mitigating the impact of 21st Century climate change on the amount and spatial pattern of blanket peat erosion. The results of our study can be used within blanket peatland regions to inform spatially-targeted management strategies.

In peatlands, fluvial erosion can lead to a dramatic decline in hydrological function, major changes in the net carbon balance and loss of biodiversity. Climate and land management change are thought to be important influences on rates of peat erosion. However, sediment production in peatlands is different to that of other soils and no models of erosion specifically for peatlands currently exist. Hence, forecasting the influence of future climate or spatially-distributed management interventions on peat erosion is difficult. The PESERA-GRID model was substantially modified in this study to include dominant blanket peat erosion processes. In the resulting fluvial erosion model, PESERA-PEAT, freeze–thaw and desiccation processes were accounted for by a novel sediment supply index as key features of erosion. Land management practices were parameterized for their influence on vegetation cover, biomass and soil moisture condition. PESERA-PEAT was numerically evaluated using available field data from four blanket peat-covered catchments with different erosion conditions and management intensity. PESERA-PEAT was found to be robust in modelling fluvial erosion in blanket peat. A sensitivity analysis of PESERA-PEAT showed that modelled sediment yield was more sensitive to vegetation cover than other tested factors such as precipitation, temperature, drainage density and ditch/gully depth. Two versions of PESERA-PEAT, equilibrium and time-series, produced similar results under the same environmental conditions, facilitating the use of the model at different scales. The equilibrium model is suitable for assessing the high-resolution spatial variability of average monthly peat erosion over the study period across large areas (national or global assessments), while the time-series model is appropriate for investigating continuous monthly peat erosion throughout study periods across smaller areas or large regions using a coarser-spatial resolution. PESERA-PEAT will therefore support future investigations into the impact of climate change and management options on blanket peat erosion at various spatial and temporal scales.

Fire is known to impact soil properties and hydrological flow paths. However, the impact of prescribed vegetation burning on blanket peatland hydrology is poorly understood. We studied 10 blanket peat headwater catchments. Five were subject to prescribed burning, while five were unburnt controls. Within the burnt catchments, we studied plots where the last burn occurred ∼2 (B2), 4 (B4), 7 (B7), or greater than 10 years (B10+) prior to the start of measurements. These were compared with plots at similar topographic wetness index locations in the control catchments. Plots subject to prescribed vegetation burning had significantly deeper water tables (difference in means = 5.3 cm) and greater water table variability than unburnt plots. Water table depths were significantly different between burn age classes (B2 > B4 > B7 > B10+) while B10+ water tables were not significantly different to the unburnt controls. Overland flow was less common on burnt peat than on unburnt peat, recorded in 9% and 17% of all runoff trap visits, respectively. Storm lag times and hydrograph recession limb periods were significantly greater (by ∼1 and 13 h on average, respectively) in the burnt catchments overall, but for the largest 20% of storms sampled, there was no significant difference in storm lag times between burnt and unburnt catchments. For the largest 20% of storms, the hydrograph intensity of burnt catchments was significantly greater than those of unburnt catchments (means of 4.2 × 10−5 and 3.4 × 10−5 s−1, respectively), thereby indicating a nonlinear streamflow response to prescribed burning. Together, these results from plots to whole river catchments indicate that prescribed vegetation burning has important effects on blanket peatland hydrology at a range of spatial scales.

Congenital Anomalies in Canada 2013: A Perinatal Health Surveillance Report is the second national surveillance report from the Public Health Agency of Canada dedicated to congenital anomalies. It provides comprehensive data on congenital anomalies in Canada, focussing on 6 categories of congenital anomalies: Down syndrome, neural tube defects, congenital heart defects, orofacial clefts, limb deficiency defects and gastroschisis. The report presents national-level birth prevalence data and temporal trends, provincial and territorial estimates, and international comparisons. Known risk factors, prevalence-related impacts of prenatal diagnosis and preventative measures are also discussed.Note de synthèse - Anomalies congénitales au Canada 2013 : Rapport de surveillance sur la santé périnatale du Système canadien de surveillance périnatale de l’Agence de la santé publique du Canada.Anomalies congénitales au Canada 2013 : Rapport de surveillance sur la santé périnatale est le deuxième rapport national de surveillance des anomalies congénitales publié par l’Agence de la santé publique du Canada. Il dresse un portrait d’ensemble des anomalies congénitales au Canada en utilisant principalement six grandes catégories : le syndrome de Down, les anomalies du tube neural, les cardiopathies congénitales, les fentes labio-palatines, les malformations des membres et le gastroschisis. Le rapport fournit des données et des tendances à l’échelle nationale concernant la prévalence à la naissance, des estimations par province et par territoire et des comparaisons internationales. Sont également abordés les facteurs de risque connus, les effets du diagnostic prénatal sur la prévalence à la naissance et les mesures de prévention.

It is increasingly recognised that tackling land degradation through more sustainable land management depends on incorporating multiple perspectives by using a variety of methods at multiple scales, including the perspectives of those who manage and/or use the land. This paper reports experience implementing a previously proposed methodological framework that is designed to facilitate knowledge sharing between researchers and stakeholders about land degradation severity and extent, and sustainable land management options. Empirical findings are presented from the Botswana site of the EU-funded Desertification Mitigation and Remediation of Land project. The paper reflects upon the challenges and benefits of the proposed framework and identifies a number of benefits, notably related to insights arising from the integration of local and scientific knowledge, and the ownership of the sustainable land management strategies that emerged from the process. However, implementing the framework was not without challenges, and levels of poverty and formal education may limit the implementation of the framework in some developing world contexts.

Since water resources are scarce across dryland areas, including Mediterranean Europe and much of Africa, the sparseness of meteo and hydrometric networks require the application of indirect methods to make best use of existing resources, and to plan for future needs in a world of changing climates. Although remote sensing methods may be among the most effective for present conditions, they have limited forecasting potential. Here we apply coarse scale modelling approaches, based on partitioning precipitation between evapotranspiration, runoff and recharge , and making use of CRU interpolated gridded climate data for the present and recent past, with offsets for future conditions based on GCM scenarios. These methods can be applied at a range of scales: first to provide broad regionalisation patterns for hydrological response and second to provide default background data that can be supplemented by local data to provide site-specific advice to land managers. These methods have been applied in the EU MIRAGE project to regionalise the frequency of the dry phase in temporary streams during the Mediterranean summer, to help define reference ecological conditions across the humid to arid spectrum. They are also being applied in the EU WAHARA project to support the sharing of appropriate good practice for water harvesting in semi-arid Africa, in partnership with researchers in Ethiopia, Tunisia, Zambia and Burkina-Faso. Initial results show where it appropriate to consider transferring techniques between climatically comparable areas.

Delay to breast cancer diagnosis following an abnormal screening result is associated with anxiety and personal disruption. We assessed the patterns and timeliness of diagnostic follow-up after breast cancer screening for women with abnormal results who attended organized screening programs in 7 provinces.Using data from the Canadian Breast Cancer Screening Database, we identified 203,141 women aged 50-69 years who underwent screening in 1996 through provincially organized breast cancer screening programs in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Nova Scotia and Newfoundland. We prospectively followed women with an abnormal screening result through to the completion of the assessment process. We evaluated the waiting times from screening examination to first assessment, from screening examination to first imaging, from screening examination to diagnosis and from first assessment to diagnosis for 13,958 women, stratified according to screening program, mode of detection, whether a biopsy was performed and whether cancer was diagnosed.We observed considerable variations between and within programs in the time to diagnosis. The median time from screening examination to first assessment was 2.6 weeks. The median time from screening examination to diagnosis was 3.7 weeks; this time increased to 6.9 weeks for women undergoing biopsy. Even when no biopsy was performed, 10% of the women waited 9.6 weeks or longer for a diagnosis, as compared with 15.0 weeks or longer for 10% of the women undergoing biopsy. Among the women who had a biopsy, the use of core biopsy was associated with a shorter median time to diagnosis than was open biopsy, and those found to have cancer had shorter waiting times than women with benign biopsy findings.Women undergoing assessment of an abnormal breast cancer screening result waited many weeks for a diagnosis, especially when a biopsy was performed. To ensure that targets for timeliness, adopted nationally in 1999, are realized, improved models of care or dissemination of existing efficient techniques to reach a diagnosis will be needed.