Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban University of Technology, 2009. / Modern surfing dates as far back as the 1960’s when the first amateur and professional surfing competitions were held (1). Since these humble beginnings, surfing has enjoyed a sustained growth over the last half a century, principally through increased commercialization of surfing apparel and an increased positive association with the lifestyle of surfers. Objectives: The aim of this study was to determine a retrospective cohort analysis of the injury profile of internationally competitive surfers and provide information on chronic, repetitive strain injuries suffered by them. Therefore, for the purpose of this study, the following information was gathered in order to create an injury profile: • Demographics of internationally competitive surfers competing in the Mr. Price Pro, Durban, South Africa, • Prevalence of surfing injuries, • Treatment received for injuries. Methods: This study was a retrospective, quantitative, epidemiological study (9), on the Chiropractic Student Sports Association’s (CSSA) questionnaire in order to produce a retrospective cohort analysis of the injury profile of internationally. On entry into the Chiropractic treatment facility, the surfer is requested to complete their portion of the CSSA questionnaire. Thereafter the senior intern then takes a brief case history, elaborating on the information provided by the surfer, followed by a standard clinical assessment related to the anatomical region or list of differential diagnoses based on the history. iv The study was limited to any surfer, male or female, who was competing on the World Championship Tour or the World Qualifying Series and registered to compete in the Mr. Price Pro. Results: Chronic injuries made up for 52.7% of surfing injuries, with the spine and surrounding musculature being the most commonly affected regions. Factors associated with injury were the repetitive nature of certain aspects of surfing and the age of the surfer. The findings in this study concurred with previous literature with the respect to sustaining of an injury related to surfing. However, many of the findings in this study differed to that of previous literature with respect to the common site of injury. The spine was the most common site of injury, as opposed to lower extremities as had been previously reported. The factors associated with injury also differed somewhat from previous literature. Therefore, this warrants further investigation with due consideration to the recommendations from this study.

The purpose of this study is to examine the differences and similarities regarding verbal politeness in greetings and requests in Swedish and the Chilean variety of Spanish. A survey with 12 questions, both open-ended and closed-ended, has been distributed to 20 native speakers of the two languages. Thus, the questions have been analyzed both quantitatively and qualitatively. The results show that the perception that the Swedes and the Chileans have about verbal politeness is similar, since the speakers of both languages see it as a way to show respect towards others. The study also shows that Swedes and Chileans share a similar view upon politeness, i.e. as a social norm that facilitates social interaction between people.

Background: In health status assessment, patient-reported outcome (PRO) measures are tools used to elicit important and measurable information from patients to better understand the impact of health conditions on their lives. Such impacts are considered latent constructs, or variables that cannot be observed or measured directly. Instruments intended to assess latent constructs must satisfy certain development, psychometric, and scaling standards through the generation of both qualitative and quantitative evidence to demonstrate the adequacy of its measurement properties. Health-related quality of life (HRQOL), or the subjective perception of health, is a core concept within the field of PROs. The Short Form 36 (SF-36) is one of the most commonly used PROs used to assess health-related quality of life (HRQOL).Objectives: To provide a better understanding of the performance and dimensionality of the SF-36 version 2 in a cross-sectional sample of patients with multiple sclerosis (MS) on an item, subscale, and higher-order factor structure level using different measurement methods grounded in classical test theory (CTT), factor analysis, and item response theory (IRT).Methods: This was a post hoc analysis of a cross-sectional dataset. Patients with MS were recruited to participate in an online survey asking a variety of questions related to their health and treatment seeking behaviors. The SF-36 was one of the questionnaires included in the survey. Items and individual subscales were evaluated using a multi-trait/multi-item correlation matrix to assess item-to-subscale relationships, including item discriminant validity with other subscales. Unidimensionality for select SF-36 subscales was assessed through confirmatory factor analysis (CFA). Internal consistency reliability (Cronbach's alpha) was evaluated for each subscale. Patient-reported disability, depression, and current symptom exacerbation status were evaluated relative to SF-36 subscale scores to assess convergent validity, discriminant validity, and known-groups validity. Higher-order factor models of the SF-36 were tested to evaluate dimensionality of the instrument, including a two-factor second-order factor model, a bifactor model, and a statistical comparison between the bifactor model and its corresponding nested model. Unidimensionality was further evaluated through the use of graded response IRT models. The relative fit of traditional versus discrimination-constrained models was tested using a -2 loglikelihood ratio test, followed by an evaluation of item-level properties for fit (S-X² statistics), local dependence, and further assessment of model parameters (discrimination parameters, location parameters, option response functions, and test information curves). Person location parameters were also estimated to compare scale information to the location of patients along the latent construct. Results: A total of 1,052 respondents completed the survey. Unidimensionality of individual subscales evaluated via CFA all had confirmatory fit indices (CFI)>0.90, butroot mean square error of approximation [RMSEA] values all exceeded 0.08. All IRT graded response models showed a statistically significant improvement in model fit when item discrimination was freely estimated. Each subscale from the IRT models had at least one mis-fitting item across all unidimensional scales tested (S-X² p-value>0.05), and nearly all subscales tested showed item pairs with signs of local dependence. Cronbach's alpha was>0.80 for all subscales except for General Health [GH] (alpha = 0.78). SF-36 subscales most closely related to physical aspects of health status had the strongest relationship to disability status (physical functioning [PF], r = -0.82, and role physical [RP], r = -0.57). Subscales more closely related to mental health had the largest effect sizes between patients with versus without depression (0.88 for mental health [MH] subscale) and the smallest effect sizes between patients reporting currently experiencing versus not experiencing an exacerbation of their symptoms (0.48 for role emotional [RE]subscale). Both CFA and IRT analyses showed lack of compelling evidence supporting unidimensionality upon combining items from the PF, RP, bodily pain [BP], and GH subscales to form the Physical-21, and upon combining items from the VT, role emotional (RE), social functioning (SF), and MH subscales to form the Mental-14. Higher-order factor models showed good model fit, with CFI>0.90 in all cases and lower RMSEA values than seen for the individual subscales (0.077 to 0.107). The bifactor model fit significantly better than its nested second-order version, however, the best-fitting (i.e., highest CFI and lowest RMSEA) higher-order factor model was the preliminary first-order model with eight first-order factors consistent with the eight subscales of the SF-36 (CFI=0.996, RMSEA=0.077, X² = 3872.14, p<0.001). Conclusions: The SF-36 version 2 performed well when evaluated within the CTT framework, but both CFA and IRT methods revealed several limitations at the item and factor level across all subscales, due to item wording (i.e., positive versus negative), items not being sufficiently related to its latent construct, and local dependence of items within and across subscales. The appropriateness of equal weighting of responses to produce a single summary score for each subscale, as well as their further aggregation into the Physical Component Summary and Mental Component Summary scores should be reevaluated.

Quantitative microscopy deals with the extraction of quantitative measurements from samples observed under a microscope. Recent developments in microscopy systems, sample preparation and handling techniques have enabled high throughput biological experiments resulting in large amounts of image data, at biological scales ranging from subcellular structures such as fluorescently tagged nucleic acid sequences to whole organisms such as zebrafish embryos. Consequently, methods and algorithms for automated quantitative analysis of these images have become increasingly important. These methods range from traditional image analysis techniques to use of deep learning architectures. Many biomedical microscopy assays result in fluorescent spots. Robust detection and precise localization of these spots are two important, albeit sometimes overlapping, areas for application of quantitative image analysis. We demonstrate the use of popular deep learning architectures for spot detection and compare them against more traditional parametric model-based approaches. Moreover, we quantify the effect of pre-training and change in the size of training sets on detection performance. Thereafter, we determine the potential of training deep networks on synthetic and semi-synthetic datasets and their comparison with networks trained on manually annotated real data. In addition, we present a two-alternative forced-choice based tool for assisting in manual annotation of real image data. On a spot localization track, we parallelize a popular compressed sensing based localization method and evaluate its performance in conjunction with different optimizers, noise conditions and spot densities. We investigate its sensitivity to different point spread function estimates. Zebrafish is an important model organism, attractive for whole-organism image-based assays for drug discovery campaigns. The effect of drug-induced neuronal damage may be expressed in the form of zebrafish shape deformation. First, we present an automated method for accurate quantification of tail deformations in multi-fish micro-plate wells using image analysis techniques such as illumination correction, segmentation, generation of branch-free skeletons of partial tail-segments and their fusion to generate complete tails. Later, we demonstrate the use of a deep learning-based pipeline for classifying micro-plate wells as either drug-affected or negative controls, resulting in competitive performance, and compare the performance from deep learning against that from traditional image analysis approaches.

Techniques of performance-based design in fire safety have developed notably in the past two decades. One of the reasons for departing from the prescriptive methods is the ability of performance-based methods to form a scientific basis for the cost-risk-benefit analysis of different fire safety alternatives. Apart from few exceptions, observation of past fires has shown that the structure’s contribution to the overall fire resistance was considerably underestimated. The purpose of this research is to outline a risk-based design approach for structures in fire. Probabilistic methods are employed to ascertain uniform reliability indices in line with the classical trend in code development. Modern design codes for complex phenomena such as fire have been structured to facilitate design computations. Prescriptive design methods specify fire protection methods for structural systems based on laboratory controlled and highly restrictive testing regimes. Those methods inherently assume that the tested elements behave similarly in real structures irrespective of their loading, location or boundary conditions. This approach is contested by many researchers, and analyses following fire incidents indicated alarming discrepancy between anticipated and actual structural behaviour during real fires. In formulating design and construction codes, code writers deal with the inherent uncertainties by setting a ceiling to the potential risk of failure. The latter process is implemented by specifying safety parameters, that are derived via probabilistic techniques aimed at harmonising the risks ensuing different load scenarios. The code structure addresses the probability of failure with adequate detail and accuracy. The other component of the risk metric, namely the consequence of failure, is a subjective field that assumes a multitude of variables depending on the context of the problem. In codified structural design, the severity of failure is implicitly embodied in the different magnitudes of safety indices applied to different modes of structural response. This project introduces a risk-based method for the design of structures in fire. It provides a coherent approach to a quantified treatment of risk elements that meets the demands of performance-based fire safety methods. A number of proposals are made for rational acceptable risk and reliability parameters in addition to a damage index with applications in structural fire safety design. Although the example application of the proposed damage index is a structure subjected to fire effects, the same rationale can be easily applied to the assessment of structural damage due to other effects.

Thesis (PhD)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: A flood event in the town of Mariental, in 2006, raised a sudden awareness regarding the state of dam safety in Namibia. Although damage was caused at the town, the flood was not extreme; it was approximately a one in fifty year event. The concern, however, was the increase in risk imposed on the town due to the temporary malfunctioning of the back-up power system: should the secondary back-up system also have failed, the embankment could have overtopped with subsequent failure; a catastrophe. The Rational Quantitative Optimal (RQO) approach, presented in this dissertation, provides a robust risk evaluation model which produces a definitive result for the reduction of risk from the overtopping of earth-fill dams. The model is based on principles of risk, but an assessment of a portfolio of dams provides discrete optimal results, not expressed in terms of probability. All the steps that the methodology comprises have been developed exhaustively and propose to address concerns raised by dam owners and decision makers regarding risk-based dam safety: a transparent framework for decision making related to public safety, which will also appeal to the technically minded portfolio manager looking for a purely quantitative procedure to assist in the decision making process. The RQO process is applied mechanistically, not requiring judgement from the decision maker. It thus addresses the concern raised by dam owners regarding the probability of risk assessment being judgmental. Risk in this dissertation is associated with embankment dams and concomitant external erosion, which globally is the single largest cause of failure of these dams. This specific failure mechanism, in particular, is a threat in Namibia, since other mechanisms, such as internal erosion, poses very little risk to the type of embankment dams typically found in Namibia. Therefore, for practical purposes, the extreme flood hydrology in Namibia is revisited and applied to real dams in the RQO model. Extreme flood hydrology in Namibia has, for the past thirty years, largely been based on the South African Department of Water Affairs Technical Report 137 (TR 137) of 1988; This report proposes an empirically established upper limit of flood peaks, called the Regional Maximum Flood (RMF), which is associated with an annual recurrence interval of 10 000 years, as shown in this study from probabilistic analysis which included palaeoflood data. The updated flood model incorporates thirty years of additional systematic data, as well as palaeoflood data that has resulted from a new approach. The new data have provided an increase in the K‒value boundaries for some of the regional flood zones. A revised graphical distribution of the K‒value zones for Namibia is presented and is proposed as a replacement for the current model. / AFRIKAANSE OPSOMMING: ‘n Vloed in die dorp Mariental, in 2006, het belangstelling in damveiligheid in Namibia aangewakker. Alhoewel skade aangerig is aan die dorp, was dit nie ‘n besonderse groot vloed nie; dit was ‘n vloed met ongeveer ‘n vyftig jaar herhalingsperiode. Kommer met betrekking tot die voorval spruit uit die toename in risiko weens die bystand kragaanleg wat gefaal het toe dit nodig was. Indien die tweede bystand stelsel ook nie gewerk het nie, kon die dam se wal oorstroom het, wat tot katastrofiese faling van die dam kon gelei het. Die Rasionele Kwantitatiewe Optimale benadering (RQO) vir damveiligheid, wat verlaging in risiko teen oorstroming van grondvul damme teweegbring word hier voorgestel. Die model is gebaseer op beginsels van risiko analise, maar die resultaat vir ‘n portefeulje van damme word uitgedruk nie in waarskynlikheidsterme nie, maar in terme van ‘n diskrete optimale antwoord. Die metode is in diepte ontwikkel en spreek onsekerhede aan waarvoor dam-eienaars en besluitnemers te staan gekom het; ‘n deursigtige besluitnemings proses wat die veiligheid van die publiek eerste stel, en wat ook aanklank sal vind by ‘n tegnies georiënteerde bestuurder wat ‘n kwantitatiewe oplossing soek vir besluitneming by ‘n portefeulje van damme. Die RQO proses is meganisties in sy toepassing; dit verg geen oordeel van die besluitnemer nie. Sodoende spreek dit ‘n bekommernis aan wat menige dam-eienaars het oor die onpartydigheid of onbevooroordeeldheid in risiko besluitneming. Risiko word in hierdie studie geassosiëer met grondvul damme en eksterne erosie. Eksterne erosie is op internasionale vlak die grootste enkele oorsaak van faling van grondvuldamme. Hierdie falingsmeganisme is ook die grootste risiko van faling wat in Namibia voorkom, aangesien interne erosie nie by rotsvul damme, wat tipies in Namibia gebou word, ‘n groot risiko inhou nie. Dus, vir die praktiese toepassing van die RQO metode, word die ekstreme vloedhidrologie van Namibië ook onder oënskou geneem. Die afgelope dertig jaar is vloedhidrologie in Namibie hoofsaaklik gebaseer op die streeksmaksimum vloed metode wat deur Kovács (1988), van die destydse Suid Afrikaanse Departement van Waterwese, opgestel is vir lande in suidelike Afrika. Dit is beskryf in die tegniese verslag, die TR 137 van 1988, van die Departement van Waterwese, Suid Afrika. TR 137 stel ‘n streeksverbonde empiries-gebaseerde boonste limiet vir vloede voor, die sogenaamde Streeks Maksimum Vloed (SMV). Hierdie studie het gevind dat die SMV vloede tipies ‘n 10 000 jaar herhalingsperiode het deur ‘n waarskynlikheidsontleding te doen van die vloeirekords en palaeovloeddata. Die opgedateerde SMV vloedmodel vir Namibie sluit in dertig jaar se addisionele aaneenlopend-gemete data, asook nuwe palaeovloed data. Die nuwe data vergroot die areas van sommige van die die K-sones, wat die streeksvloed sones voorstel. ‘n Hersiene kaart met die nuwe K-sone grense daarop aangedui word deur hierdie navorsing aangebied en word voorgestel as ‘n vervanging van die Kovács-SMV-kaart van Namibië van 1988.

This thesis considers the roles that social cognitions play in cycle commuting behaviour. Currently in the field of active travel there is a strong drive towards ecological theories, which often focus on the wider environmental factors that influence cycling. However, research into utilitarian cycling and related physical activities suggests that psychological factors also have an important role to play. In light of the current political climate within the UK and the numerous benefits that cycling for transport can incur, it was deemed important to further explore the role that social cognitions play in the decision to cycle commute. To date, there has been limited psychological research carried out into cycle commuting. Therefore, this thesis initially considers and critiques a number of relevant behavioural theories and psychological variables. The first study used semi-structured interviews along with interpretative phenomenological analysis (IPA) to explore the perception and attitudes of a group of cycle commuters (n = 8) and potential cycle commuters (n = 7) based in a workplace that supports cycling. The interest of this study was to identify if any differences and/or commonalities in social cognitions existed between the two groups. The findings indicated that potential cyclists are less aware of the range of benefits associated with cycling to work, and discussed more challenges and fewer coping strategies than regular and experienced cycle commuters. Whilst the study was inductive in nature, the findings to emerge suggest that cognitive variables involved in cycle commuting behaviour (motivations, barriers and coping strategies) could be aligned with a number of social cognition/ behaviour change theories. The second and third studies were similar in design and used cross-sectional questionnaires to investigate perceptions of barriers (Study 2 & 3), perceptions of benefits (Study 3), self-efficacy (Study 3) and decisional balance scores (Study 3) related to cycle commuting behaviour. These social cognitions were measured in relation to stage of change, gender and job role. Both investigations were carried out in workplaces that support cycling. Study 2 (n = 831) highlighted the important role that perceptions of barriers play in cycle commuting behaviour. Study 3 (n = 337) built on the previous two studies findings and demonstrated that perceived barriers and benefits and self-efficacy associated with cycle commuting were all significant predictors of cycle commuting behaviour, with barriers being the most powerful. The forth and final study used a pre- and post-test control trial design to evaluate a psychologically-orientated intervention that was theoretically based on the Transtheoretical Model of Behaviour. The intervention was designed for people who were contemplating cycling to work. The small-scale intervention evaluation included one pre-test and two post-test measures that were collected over a four month period. The before and after results revealed that the intervention group (n = 17) significantly decreased their perceptions of barriers and progressed closer to action. This may be explained by increases in some of the processes of change that were reported. The control group (n = 16) reported no significant changes in their social cognitions, actions or in their use of the processes of change. These results suggest that the intervention designed, developed and trailed in this thesis is successful at encouraging people to cycle to work. Together, these four studies demonstrate that social cognitions do play an important role in cycle commuting behaviour. Throughout this thesis, perceptions of barriers associated with cycle commuting have shown to play a powerful role in explaining and predicting behaviour. Whilst barriers can be both perceived (subjective) and actual (objective), the small-scale intervention study has demonstrated that by psychological intervention alone perceptions of barriers can be significantly reduced.

Environmental and physical conditions are considered primary drivers of fish community assemblages. The anthropogenic alteration of aquatic ecosystems is implicated as a primary threat to fisheries worldwide. In riverine ecosystems, river-wide barriers may alter natural fluvial processes and hinder fish movement through the system. In this study, I use data collected from two successive years (2008 and 2009) of intensive quantitative electrofishing Casselman and Marcogliese (2008, 2009) performed in different seasons (late fall and late summer) on the lower Ottawa and Mississippi River systems, Ontario, to investigate the effects of sampling season, distance from the river mouth, water temperature, conductivity, rank of velocity and dams on fish abundance, species richness and the Shannon-Weiner Index (SWI) as a measure of species diversity. Sampling in late summer, compared with late fall, resulted in greater species richness and diversity. Colder water temperature affected community composition, and species richness decreased upstream, while diversity did not change. In both seasons, the distance from the river mouth influenced fish community composition, whereas dams appeared to have no effect. This suggests that the continuous gradient model of the River Continuum Concept (RCC) would be applicable in these fragmented systems, which are not heavily altered by fractionation. To effectively manage cost and accuracy when collecting fish community data in large rivers, it is essential to sample strategically during seasons likely to maximize diversity and richness. Sampling intensively during warm water months in various river reaches would likely provide the most complete representation of fish assemblage. / Thesis (Master, Biology) -- Queen's University, 2013-01-17 15:36:05.658

This thesis considers some of the main issues surrounding the quantitative models that have been developed to reconstruct vegetation from pollen assemblages. Conducted within a pine dominated woodland, a palynologically difficult landscape, to determine vegetation changes over the late Holocene the results highlight the complexities of undertaking such studies in these contexts. Pollen productivity estimates were calculated from moss samples over the woodland using complete sets and derived subsets to detect influences of sampling design on resultant model output. Differences in the PPE sets were compared using reconstructions from simulation models in comparison to observed vegetation patterns. The results indicate that both parameter calculation and model reconstructions were influenced by the landscape form and composition. Sensitivity of the models to such small variations in parameter values heightens the need for robust data generation and increased investigation to controlling factors on pollen productivity. Performance of the reconstruction models experienced variation with respect to deposition basin size and site specific characteristics. Overall, the regional reconstructions proved to generate more confident estimates of vegetation cover whilst local scale reconstructions were subject to greater variability. Comparison of the quantitative modelling to standard interpretation and the modern analogue approach shows contrasts between the results obtained with respect to limitations associated with each method and the time frames, recent (ca. 100 years) and longer (ca. 3000 years), over which they were applied. Consequently, no one quantitative approach could be identified as being superior as site specific variations were recognised in relation to the most suitable approach. In response, a hierarchical technique is proposed to utilise the benefits of each technique and to obtain detailed information to strengthen interpretations. However, it is stressed study specific constrains that determine the available resources will influence the ability to fully apply this composite approach.

No description available.