The intuitive link between a runner’s gait and their metabolic cost of running, or running economy (RE), has led to many trying to compare the running mechanics of economical runners to those of less economical runners. However using this approach has created controversy about whether running mechanics meaningfully contribute to RE. Additionally only a limited number of studies use a broad, explorative, inter-disciplinary approach, encompassing physiological parameters, flexibility, kinematics, kinetics and muscular activity. The purpose of this thesis was to primarily assess ‘self-optimisation’ through considering acute and short-term adaptations to running mechanics and RE. To assess the biomechanical and physiological mechanisms behind changes to RE three studies were conducted, in addition to a fourth study which investigated biomechanical familiarisation. Study one investigated whether there were any biomechanical or physiological changes in beginner runners after 10 weeks of running and whether any of these changes contributed to a change in RE. There was an 8.4% improvement in RE (224  24 vs. 205  27 mL.kg-1.min-1) and an increase in treadmill time-to-exhaustion (16.4  3.2 vs. 17.3  2.7 min), but no change in ̇ 2max, minute ventilation or heart rate. Several kinematic, kinetic and flexibility measures were found to change over time, but joint moments and stiffness remained similar, with knee extension at toe-off, rearfoot velocity at touch down and timing of peak dorsiflexion explaining 94.3% of the variance in change in RE. Results from study one suggested that changes in muscular activity might have contributed to kinematic differences, and subsequently an economical gait. Specifically, as joint moments were unchanged after 10 weeks it is possible that muscular coactivation may have changed since varying levels of agonist-antagonist activation can produce the same joint moment. Consequently study two examined the relationship between muscular coactivation and the metabolic cost of running, as thus far there was conflicting evidence. Results showed that in trained, recreational runners greater thigh coactivation was associated with a greater metabolic cost of running. Furthermore, the speed of running was found to affect the level of coactivation at the shank and of the flexor-flexor muscle pair, with less coactivation reported at faster submaximal speeds. The final part of the thesis focused on a manipulation investigation into barefoot (BFT), minimalist shod (MS) and shod (SH) running. Applying the novel findings from studies one and two to this topical area would hopefully provide new insight into the 3 BFT running debate. Prior to applying this knowledge of kinematic and muscular activity changes in relation to RE whilst running BFT, an investigation into the time required to become familiar with barefoot treadmill running was needed. Results revealed that barefoot familiarisation was characterised by less plantarflexion and greater knee flexion at touch down, whilst stride length appeared to be adopted instantaneously. Reliability (intra-class correlations) and accuracy (standard error of mean) of the kinematic data appeared strongest once individuals had been running for 20 mins. Furthermore there were no significant differences in the kinematics after 20 mins of running. The final study considered how changing the levels of proprioception and cushioning (BFT, MS and SH) influenced RE and the potential running mechanics that contributed to any changes in RE. The ramifications of such changes on injury risk were also considered by investigating impact accelerations, effective mass and pronation. Additionally, the effect of naturally changing stride length from a shorter BFT stride to a longer SH stride on RE were examined. Heightened proprioception and no external cushioning (BFT running) appeared to improve RE by at least 5% regardless of stride length, when compared to SH running with a SH stride length. However less proprioception and no external cushioning (MS running) only improves RE, compared to SH running with a SH stride length, when runners run with their SH stride length, rather than their shorter BFT stride length (~2.5% shorter). Improvements in RE are attributed to a lower vertical oscillation and effective mass, greater dependency on efficient, Type I muscles i.e. tibialis anterior, and less plantarflexion at toe-off. However higher impact accelerations, earlier heel off and low pronation angles, suggest there may be an increase in injury risk. Therefore the findings from this thesis have demonstrated that runners naturally selfoptimise the way they run. This is seen both as an acute (changes in footwear) and short-term (10 weeks) response to changing running gait. Study two demonstrated that economical runners appear to use different muscular strategies, with study one and four showing they also adopt specific movement patterns that may promote efficient storage and release of elastic energy. Additionally study three found that runners can become familiar with BFT treadmill running in 20 minutes. It is also important to note that economical biomechanical adjustments do not always favour a reduction in injury risk. But the thesis findings seem to suggest that perhaps performance denominates in terms of self-optimisation, rather than injury prevention.

Modern literature has many research in the field of entrepreneurship, but most of them do not explain the characteristics of entrepreneurial activity in developing countries. Thus, this research uses  regression analysis of panel data for the cross-country analysis of factors influence the level of entrepreneurial activity in 52 developing countries. The paper provides empirical information about the individual characteristics, regulatory standards countries, as well as some macroeconomic indicators. Individual factors (gender, age), indicators of respondents’ self-evaluation and assessment of the environment, in which they are located have a significant impact on entrepreneurial activity in developing economies. In terms of macroeconomic indicators, it was concluded on the positive effects of GDP growth and the lack of impact of unemployment on the level of entrepreneurial activity.

Rising obesity rates have generated serious policy concern and public interest. Along with biological and genetic factors contributing to weight gain, dietary and physical activity behaviours are considered the main determinants of individual body weight. In order to tackle the increasing obesity problem and change individual behaviour, effective policy interventions need to be developed which target specific groups within the population. Economic frameworks that have been designed to model individual choices can be applied to improve the understanding of how individual characteristics and socio-economic factors affect weight-related behaviours and body weight. This thesis uses data from the Scottish Health Survey and the HILDA (Household, Income, and Labour Dynamics in Australia) survey to empirically analyse (1) if average BMI and socio-economic characteristics differ across combinations of weight-related behaviours, (2) how diet and physical activity behaviours, as well as their determinants, can be adapted to explain BMI on average, (3) how determinants of BMI impact differently across a conditional BMI distribution, and (4) to what degree a change in BMI over time can be explained by changing influences. While previous economic research did not consider the combined effect of dietary and physical activity behaviours on body weight, this work will investigate the relationship between the weight-related behaviours and individual BMI on average and across the conditional BMI distribution to identify areas for policy interventions. Results indicate that an increase in individual physical activity is an effective measure to target individual weight. Although the energy balance framework suggests a promotion of both weight-related behaviours and traditional weight management measures promote a reduction in caloric intake, the analyses have shown that physical activity is the predominant behaviour regarding the influence on individual BMI (compared to individual diet measured by quality proxies rather than the overall caloric intake).

No description available.

Master of Science / Department of Kinesiology / Emily Mailey / Background: Many adults spend a majority of their time at work engaging in primarily sedentary behaviors. Creating a health-promotion program can increase awareness of the importance of physical activity as well as provide benefits to the employee and employers. The main purpose of this study was to compare physical activity, motivation and support levels between participants and non-participants of a workplace movement challenge. Additionally, we examined factors associated with average steps and reasons for participating and not participating in the challenge.   Methods: Information about the four-week movement challenge was sent by email to all employees. Steps were monitored by personal activity trackers (e.g. pedometer, Fitbit, etc.) and self-reported at the end of each week. Steps were averaged within departments and a departmental leader board was posted weekly to encourage competition across campus. All individuals who participated in the program were invited to complete a brief follow-up survey one month later. Non-participants of the program were invited to complete a similar survey at the same time. To analyze the data we used t-tests and correlation tests. Results:  Of the 6,798 employees who received an email about the Movement Challenge, 650 (9.6%) submitted at least one survey and 376 completed all four surveys. Results of the follow-up survey showed employees with a departmental team leader accumulated significantly more steps than employees without a team leader (p= 0.03). Additionally, average steps were significantly associated with both social support (r=.21; p<.01) and motivation subscales including identified regulation and intrinsic regulation. Those who enrolled in the program reported they liked the tracking/accountability and departmental competition best. Participants of the program reported greater total physical activity (p< .001), total social support (p< .001), introjected regulation (p< .001), identified regulation (p< .002) and intrinsic regulation (p< .01) levels compared to those who did not enroll in the program. Conclusion: Worksite wellness campaigns can increase physical activity among employees, but additional strategies are needed to increase participation. The results of this study suggest future programs should increase competition and increase contribution from team leaders. They should also include team support across departments to build support within the program.

Student Number : 0009899J - PhD thesis - School of Therapeutic Sciences - Faculty of Health Sciences / The genus Eriocephalus commonly known as ‘wild rosemary’, ‘Cape snow bush’, or ‘kapokbos’ is a member of the family Asteraceae (tribe Anthemideae). The genus is endemic to southern Africa, with the highest concentration of species in the Western and Northern Cape. The genus comprises 32 species and a total of 42 taxa, which are distributed in South Africa, Namibia, Botswana, and Lesotho. The characters used in species delimitation are purely based on morphological variation in floral and foliar parts and are highly homoplastic due to phenotypic plasticity. In many cases these features are not sufficiently distinctive, as some taxa tend to exhibit dimorphism in some character states such as the presence of opposite and alternate leaves. In some species there is extensive intergrading of the major diagnostic characters leading to uncertainty in species delimitation. Both chemical and molecular characters were used in this study in an attempt to evaluate current species delimitations in the genus, along with species-level relationships and affinities. The genus is also economically important with some of its members used as medicinals, fodder, perfumes, and cosmetics. This warrants investigation into the phytochemistry and biological activity of these species in order to determine a scientific rationale for their traditional uses. For this reason, the antimicrobial, antiinflammatory, antioxidant activities, and inhibition of acetylcholinesterase by the volatile oils and leaf extracts of the genus, which are relatively unknown for most members of the genus, were also investigated. Representatives of 22 species of the genus, eight of which were from Namibia and 14 from South Africa were collected from wild populations. In most cases multiple collections per population per species were considered. Aerial plant parts were hydrodistilled to obtain the essential oils, and phenolics were extracted from leaves using acetone. Essential oils were analysed by thin layer chromatography (TLC), gas chromatography (GC), gas chromatography coupled to mass spectroscopy (GC/MS), and phenolics were analysed using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC/UV). Biological assays were carried out using the 5-lipoxygenase enzyme to evaluate antiinflammatory activity; disc diffusion and microtitre plate dilution assays were used to assess antimicrobial activities of selected fungi and bacteria; the TLC-DPPH and DPPHmicrotitre methods were used to investigate antioxidant activities and a TLC-bioautographic assay was used for testing the inhibition of the acetylcholinesterase enzyme. Total genomic DNA was extracted from silica dried leaf material. The non-coding plastid DNA regions, the psbA-trnH intergenic spacers and the internal transcribed spacer (ITS) region of nuclear ribosomal DNA were amplified, and sequenced and analysed using the parsimony algorithm. The essential oils are largely comprised of acyclic, monocyclic, and bicyclic regular and irregular mono- and sesquiterpenes of various structural groups. Two hundred compounds were noted in the essential oils with some of the common constituents being; α- and β-pinene, yomogi alcohol, ρ-cymene, 1,8-cineole, camphor, 4-terpineol, spathulenol, caryophyllene oxide, α-copaene and β-caryophyllene. Most of the species have a relatively high content of 1,8-cineole and camphor. Twenty-two chemotypes were noted and the potential for commercial development in the flavour, fragrance and pharmaceutical industries has been recorded. Among the favourable chemotypes noted includes the camphor, 1,8-cineole, bisabolol oxide B and nerolidol rich oils. However, due to the extensive variability in the essential oil profiles, standardization of oils in commercial development is crucial. The leaf extracts comprised of flavonoids with the flavones and flavanones as the major structural types present in most species. The terpene and flavonoid chemistry of the genus is highly divergent even among multiple individuals of the same species and hence not a good taxonomic marker for specific delimitation as no coherent groups was evident although some phytochemical congruence has been noted between some of the taxa. The DNA sequence data revealed lack of variability in the non-coding regions psbA-trnH and trnL-F among species of the genus. The nuclear DNA region (ITS) was variable but the number of characters separating taxa was too few for resolution of relationships between taxa. Presence of highly divergent paralogous repeats of ITS were also noted in some taxa. The combination of molecular and chemical data did not resolve the species delimitation problems due to the highly variable distribution of characters within a single species. The patterns of variation observed in the genus may be attributed to chemical convergence, divergence, hybridisation, differential gene expression, polymorphism and allelochemical diversification among other factors. The lack of coherence in the phylogenetic and phenetic groupings of the various taxa implies that the current species boundaries may not be a true reflection of natural taxonomic entities. The use of multiple taxa in taxonomic studies is strongly recommended due to the extensive variability noted in the chemical profiles of the taxa that is also depicted in the phylogenetic histories. It also implies that caution should be taken in bioprospecting for new natural products for commercial development, as plant chemical profiles especially from the same species can be very variable. This implies carrying out exhaustive population and genetic studies for evaluation of diversity in the study group. In the antimicrobial assay, the oils were more active against the Gram-positive bacteria (2-16 mg/ml) and yeasts (1-16 mg/ml). Bacillus cereus and Cryptococcus neofomans were the most susceptible pathogens to the oils. The extracts exhibited low activity against the test pathogens except E. aromaticus and E. pinnatus with activity of 0.2 mg/ml against Staphylococcus aureus and Bacillus cereus respectively. The susceptibility of the fungal pathogens Cryptococcus neoformans and Candida albicans and the Gram-positive bacteria Bacillus cereus to the oils and extracts is an indication of the potential for use of the members of the genus as natural antibiotics. The essential oils exhibited antiinflammatory activities with IC50 values ranging between 19.0-98.6 μg/ml. The oils did not show antioxidant activity at the starting concentration of 100 μg/ml but the acetone leaf extracts exhibited antioxidant activities with IC50 values ranging between 21.5-79.6 μg/ml. The essential oils showed inhibitory activity against acetylcholinesterase enzyme. The biological activity of the oils indicates that most of the traditional uses are influenced by the presence of the oils. The in vitro biological activity of the essential oils and extracts against the test pathogens provides a scientific basis for the use of some of the members in traditional herbal remedies and validates the use of some of the members of the genus for treatment of respiratory tract infections, gastro-intestinal disorders, mental conditions, dermal infections, and inflammation. The study records the biological activities for some of the species for the first time and their potential for use in flavourings, perfumery, cosmetics, as sources of antimicrobial drugs, permeability enhancers in pharmaceutical formulations and for use as industrial oils.

The placenta is responsible for mediating fetal growth and development, thereby influencing health across the lifespan. Physical activity (PA) confers benefits to mother and baby during pregnancy, but little is known about its impact on the placenta. There were two purposes of this study: i) to determine if maternal PA during pregnancy influences placenta mitochondrial protein content and function, and ii) to determine if there were differences in placenta mitochondrial protein content and function in different regions of the placenta, namely proximal or distal to the centre of the placenta. Healthy women between 12-28 weeks gestation were recruited, and free-living PA was objectively assessed at multiple time points during pregnancy using an accelerometer. Participants were grouped by minutes of moderate-to-vigorous PA (MVPA) per day. Placenta tissue samples were collected from central and distal placental regions immediately post-birth and were used for two separate analyses. Half of the samples were flash frozen in liquid nitrogen and used for western blot analysis of mitochondrial complex I-V proteins. Fresh mitochondria were isolated from the other half of the samples, and high-resolution respirometry was used to measure placental mitochondrial respiration. There were significant positive correlations between maternal PA and mitochondrial protein content in peripheral tissue samples, but protein content was significantly higher in central tissue compared to peripheral tissue samples. In addition, state 3 respiration was higher in central tissue samples of placentas from participants with high MVPA compared to participants with low MVPA. Finally, complex I protein was higher in central tissue samples of placentas from female offspring compared to placentas of male offspring. However, many of these results are underpowered and further study is warranted. This study provides new avenues to explore the relationship between PA and placenta mitochondria in healthy populations.

Chan Siu Hong. / "December 1999." / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (p. 172-192). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

The East African Rift System is the world's major continental rift. While much geophysical and petrological attention has been paid to it, at least in the eastern branch ("Eastern Rift"), comparatively little research has been carried out into the geochemistry of rift fluids, despite the potential benefits to theoretical and practical studies. Hydrothermal activity provides the opportunity to sample a very wide range of waters and gases in the Eastern Rift. This thesis combines data from the literature with the results of the author's major investigation into Eastern Rift fluids carried out chiefly in Kenya, though with subsidiary investigations in Ethiopia and Djibouti. A synthetic approach has been adopted, whereby relationships and interactions are cross-referenced as far as possible to illuminate problems, thus demonstrating the usefulness of considering a wide range of fluids in the rift context. After reviews of physiography, geology, geothermics and hydrology of the Eastern Rift, the following topics are considered in detail: (i) chemical and isotopic evidence for water origin, movement and evolution, (ii) chemical and isotopic evidence for gas origin, movement and evolution, and (iii) fluid geothermometry. Within this context some specific aims have been pursued. The strong possibility of longdistance axial flows of groundwater has been shown by use of stable isotopic techniques. Further insights into alkaline hydrological discharge areas have been obtained by a combination of chemical and isotopic approaches. While carbon isotope ratios indicate an apparently homogeneous source of carbon dioxide, the existence of distinct mantle sources for volcanic rocks beneath different parts of the Eastern Rift has been comprehensively demonstrated by use of helium isotope ratios. Following the rather unsatisfactory performance of various gas geothermometers for evaluating geothermal system temperatures, a new relationship based on hydrocarbon breakdown has been developed. The possible use of oxygen isotopes in hydrothermal sinters as indicators of palaeoconditions has been investigated. In conclusion, topics worthy of further research in the Eastern Rift are suggested where the study of fluids would be of benefit.

This thesis investigates to what degree women developed a politicised gender consciousness and participated in political activity in Dundee in the period 1870 to 1997. It is a gender and political study on Scotland's fourth city which has three key objectives. The first is to examine whether gender was relevant in the city's history of representation and whether it made a difference to political structures, policy and activity. The second charts the advance of women in the city's political elites to determine whether they shared common interests which formed the basis for collective action, which could be characterised as women's politics. The third sets out to further our understanding of why there is a commonly-held and repeated public view that Dundee was a woman's town and that Dundee women were and are in some way radically "different" because of the city's unique industrial circumstances and the intervention of gender into local political activity. The thesis uses several sites to explore whether the women involved made a difference in terms of political outcomes. It examines parliamentary and local government elections. It looks at the emergence of trade unions, elected bodies and autonomous women's organisations. It involves an interdisciplinary exploration of issues and problems in political studies, political history, community politics and the analysis of gender relations. It is an idiographic study of gender and political activity that utilises new evidence to challenge myths associated with the object of analysis. It argues that the distinction between the voluntary welfare associations in which women were involved and political activity was often blurred. Influential women's activity which does not fall within conventional definitions of "political" activity is also highlighted. The study seeks also to place these discourses within the context of theories about representation and equality. Within political science the thesis explores empirical explanations within the context of Dundee, and contends that analysis of the situation in the city during the study period, in particular the role of middle-class women in the 20th century, goes some way to providing a flexible alternative to important feminist approaches on political participation and representation. It is also argued in this thesis that time and place are important factors in charting representation, and that they are factors seldom prominent within feminist theoretical scholarship. Thus, this thesis is as much a first women's political history of a major Scottish city as it is an important analysis of political representation and a framework for establishing new ideas about political activity in Dundee. It provides an original contribution of a historically and socially-specific location and in so doing provides a basis for further comparative work on gender and political activity and in placing tacit assumptions in the research literature in question.