No description available.

Diss. (sammanfattning) Uppsala : Univ., 2001. / Härtill 3 uppsatser.

No description available.

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.

Polyglutamine (polyQ) diseases are a group of progressive neurodegenerative disorders, which are caused by the expansion of an existing glutamine-coding CAG repeat in the coding region of disease genes. The cell nucleus is a major site of polyQ toxicity, and gene transcription is compromised in polyQ-induced neurodegeneration. Understanding the nuclear translocation of mutant polyQ proteins is therefore crucial to unfold the complex pathogenic mechanisms that underlie the neuronal toxicity of polyQ disease. The polyQ domain is the only common sequence found among different mutant disease proteins. Nuclear transport signals have been identified in some, but not all, polyQ disease proteins. The detection of those mutant polyQ proteins that carry no classical nuclear transport signal, but not their normal counterparts, in the cell nucleus suggests the existence of uncharacterized nuclear transport signals in mutant polyQ proteins. Thus, the objective of the present study is to elucidate the nuclear transport pathway(s) adopted by an expanded polyQ domain and determine its correlation with polyQ toxicity. / Through a series of genetic and biochemical studies in cell culture, mouse and transgenic Drosophila models, exportin-1 was found to modulate the nucleocytoplasmic localization of mutant polyQ protein and its toxicity. Further, mutant polyQ protein was also demonstrated to be a novel transport substrate of exportin-1. By promoting the nuclear export of mutant polyQ protein, exportin-1 suppressed polyQ toxicity by reducing the interference of mutant polyQ protein on gene transcription. It was found that the protein level of exportin-1 diminished in the normal ageing process, which would result in an exaggeration of nuclear mutant polyQ toxicity. Thus, the age-dependent decline of exportin-1 level, at least in part, accounts for the progressive degeneration observed in polyQ patients. Results obtained from this project first demonstrated that expanded polyQ domain is a nuclear export signal, and further provided mechanistic explanation of how protein nuclear transport receptors modulate polyQ toxicity. / Chan, Wing Man. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0113. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 189-203). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

Background: The Active Commuting Route Environment Scale (ACRES) was developed to study active commuters’ perceptions of their route environments. The overall aims were to assess the measuring properties of the ACRES and study active bicycle commuters’ perceptions of their commuting route environments. Methods: Advertisement- and street-recruited bicycle commuters from Greater Stockholm, Sweden, responded to the ACRES. Expected differences between inner urban and suburban route environments were used to assess criterion-related validity, together with ratings from an assembled expert panel as well as existing objective measures. Reliability was assessed as test-retest reproducibility. Comparisons of ratings between advertisement- and street-recruited participants were used for assessments of representativity. Ratings of inner urban and suburban route environments were used to evaluate commuting route environment profiles. Simultaneous multiple linear regression analyses were used to assess the relation between the outcome variable: whether the route environment hinders or stimulates bicycle-commuting and environmental predictors, such as levels of exhaust fumes, speeds of traffic and greenery, in inner urban areas. Results: The ACRES was characterized by considerable criterion-related validity and reasonable test-retest reproducibility. There was a good correspondence between the advertisement- and street-recruited participants’ ratings. Distinct differences in commuting route environment profiles between the inner urban and suburban areas were noted. Suburban route environments were rated as safer and more stimulating for bicycle-commuting. Beautiful, green and safe route environments seem to be, independently of each other, stimulating factors for bicycle-commuting in inner urban areas. On the other hand, high levels of exhaust fumes and traffic congestion, as well as low ‘directness’ of the route, seem to be hindering factors. Conclusions: The ACRES is useful for assessing bicyclists’ perceptions of their route environments. A number of environmental factors related to the route appear to be stimulating or hindering for bicycle commuting. The overall results demonstrate a complex research area at the beginning of exploration. / BAKGRUND: Färdvägsmiljöer kan tänkas påverka människors fysiskt aktiva arbetspendling och därmed bidra till bättre folkhälsa. Studier av färdvägsmiljöer är därför önskvärda för att öka förståelsen kring möjliga samband mellan fysiskt aktiv arbetspendling och färdvägsmiljöer. En enkät, ”The Active Commuting Route Environment Scale” (ACRES), har därför skapats i syfte att studera fysiskt aktiva arbetspendlares upplevelser av sina färdvägsmiljöer. Huvudsyftet med denna avhandling var dels att studera enkätens psykometriska egenskaper i form av validitet och reliabilitet, dels att studera arbetspendlande cyklisters upplevelser av sina färdvägsmiljöer. METODER: Arbetspendlande cyklister från Stor-Stockholm rekryterades via tidningsannonsering och via direkt kontakt i anslutning till färdvägen. Deltagarna besvarade enkäten ACRES. Tillsammans med skattningar från en grupp av experter och redan existerande objektiva mått användes förväntade skillnader mellan färdvägsmiljöer i inner- och ytterstaden för att studera kriterierelaterad validitet. Reliabiliteten studerades som reproducerbarhet via upprepade mätningar (test-retest). Jämförelser mellan skattningar av deltagare rekryterade via annonsering och via direkt kontakt i färdvägsmiljöer användes för att studera representativitet. Skattningar av färdvägsmiljöer i inner- och ytterstaden användes vidare för att studera färdvägsmiljöprofiler. Multipel linjär regressionsanalys användes även för att studera sambandet mellan utfallsvariabeln huruvida färdvägsmiljön motverkar eller stimulerar arbetspendling med cykel och miljöprediktorer, såsom avgasnivåer, trafikens hastighet och grönska, i innerstadsmiljöer. RESULTAT: Enkäten ACRES visade god kriterierelaterad validitet och rimlig reproducerbarhet. Det var en god överrensstämmelse mellan skattningar av deltagare rekryterade via annonsering och via direkt kontakt. Färdvägsmiljöprofilerna visade tydliga skillnader mellan inner- och ytterstadsmiljöer. Ytterstadens färdvägsmiljöer skattades som tryggare och mer stimulerande för arbetspendling med cykel än innerstadens färdvägsmiljöer. Vidare verkar vackra, gröna och trygga färdvägsmiljöer, oberoende av varandra, vara stimulerade faktorer för arbetspendling med cykel i innerstadsmiljöer. Däremot verkar höga avgasnivåer, höga trängselnivåer och färdvägar som kräver många riktningsändringar vara motverkande faktorer. SLUTSATSER: Enkäten ACRES är ett användbart instrument vid mätningar av cyklisters upplevelser av sina färdvägsmiljöer. Ett antal faktorer relaterade till färdvägsmiljön verkar vara stimulerande respektive motverkande för arbetspendling med cykel. Generellt sett på visar resultaten ett relativt outforskat och komplext forskningsområde. / <p>Örebro universitet, Hälsoakademin</p> / FAAP

Physical activity (PA) has been labelled the miracle drug (Pimlott, 2010) and participating in regular PA has ample physical and mental wellbeing benefits. However, physical inactivity remains a critical public health concern, particularly across adolescence. In England the proportion of adolescents aged 13-15 years meeting the recommended guidelines for PA decreased significantly from those at a younger age (Health and Social Care Information Centre, 2009; 2012; 2015). The adolescent years (13 18 years) have been identified as the age of greatest decline in PA, although it is possible that large declines can also be seen at younger ages (Sallis, 2000). Among girls the decline in PA is greater at younger ages (9 12 years old) and among boys it is greater at older ages (13 16 years old) (Dumith, Gigante, Domingues, & Kohl, 2011). Thus, examining behaviour of early adolescents (aged 11-13 years) is a primary focus of this thesis. Researchers have called for a more comprehensive grasp of PA correlates and determinants and their impact on behaviour (Biddle & Mutrie, 2001, 2008). This broader picture needs to incorporate longitudinal study designs to accurately portray developmental changes (Evenson & Mota, 2011). This thesis aims to work towards a better understanding of associations among variables across aspects of the ecological model in relation to PA behaviour during early adolescence. Early adolescents within their first year of secondary school (year 7, aged 11 12 years) were recruited through schools across the East Midlands, United Kingdom (UK). These participants completed various measures across an 18 month period to compile all data required for the thesis. The thesis begins with a focus on active transport as a means of commuting to school which can significantly contribute to overall PA levels (Aibar, Bois, Generelo, Bengoechea, & Paillard, 2015; Slingerland, Borghouts, & Hesselink, 2012). The distance from home to school is an important influence on the decision to use active transport; however, ecological perspectives would suggest this variable may interact with individual, interpersonal and environmental factors. Therefore, the first study of this thesis investigates whether the relationship between distance to school and active transport is moderated by (i) gender, (ii) biological maturation, (iii) perceived family support for PA and (iv) multiple deprivation. Cross-sectional results from the baseline data collected demonstrated that the relationship between distance to school and the likelihood to actively travel to school is moderated by biological maturation, multiple deprivation and family support of PA in adolescents. Further analysis revealed that late-maturing children, those from less socio-economically deprived backgrounds and children with low family support of PA are less likely to actively commute to school as distance to school increases. Due to the interaction between these variables described above, the second study focused on the variables collectively using a person-oriented approach, which aimed to classify distinct profiles of early adolescents based on correlates of PA. The outcome variables were also broadened to include active transport and overall PA across two time points. Findings from this second study illustrate that the highly supported, shortest commuters produced the highest levels of self-reported PA and that affluent, short commuters were the most likely to use active transport to travel to school. The affluent, short commuters lived a relatively short distance to school in areas of the lowest deprivation and had relative moderate family support of PA. The highly supported, shortest commuters were characterised by the highest family support of PA and lived the shortest distance to school in areas of low deprivation. Study 1 evidenced an association between biological maturation and PA behaviour; however, study 2 displayed that biological maturation did not meaningfully contribute to the class characteristics, and were not a predictor of PA. Previous evidence as to whether early, average or late maturing adolescents are more likely to disengage from PA is mixed and tends to focus on one gender only (Sherar, Cumming, Eisenmann, Baxter-Jones, & Malina 2010; Bacil, Mazzardo, Rech, Legnani, & Campos, 2015). Thus for the third study a more focused inspection of biological maturity was undertaken. Biological maturity status was investigated as a predictor of PA behaviour at two subsequent time points (6 9 months after baseline and 12 18 months after baseline) and whether there was variation across genders. Findings displayed that biological maturity status does not predict subsequent PA, with no distinction across genders. To conclude, the final study examined additional forms of PA behaviour. For children to develop and maintain healthy PA behaviours, their PA during the school day, particularly during physical education (P.E) classes is important (Owen, Smith, Lubans, Ng, & Lonsdale, 2014). Self-reported PA was divided into school-time PA (during P.E. lessons, break and lunchtimes) and leisure-time PA (after school, during evenings and weekends). The final study fully utilised the longitudinal data collected and utilised longitudinal growth modelling to describe the changes in PA behaviour across 12-18 months during early adolescence. Results displayed that school-time PA and leisure-time PA are distinct. Males; those from less deprived backgrounds and individuals with higher family support of PA all separately reported more school-time PA than their counterparts (females, those from higher deprived backgrounds and individuals with lower family support of PA) at baseline. Males and those with higher family support of PA also reported more leisure-time PA than their respective counterparts at baseline. On average, both genders decreased in school-time PA across 18 months yet for leisure-time PA, on average, there was no change over time and no significant difference in the rate of change between genders. There were no observed significant differences in the rate of change between multiple deprivation status and biological maturation across the 18 months for both behaviours. For family support, on average school-time PA decreased over time and results showed significant difference in the rate of change between individuals with lower or higher levels of family support of PA across the 18 months. On average, there was no change over time for leisure-time PA yet there was a significant difference in the rate of change between individuals and their family support of PA across 18 months. Further analysis demonstrated if an individual s family support increases, so does their leisure-time PA and vice versa. These overall key findings demonstrate the complexity of PA behaviour throughout early adolescence. This thesis works towards predicting individuals, correlates and determinants that may be susceptible to physical inactivity and/or a decrease in activity over time. Results can be used to target and direct PA intervention work.

<p>Syftet med denna uppsats var att undersöka vilka faktorer som påverkar hur förvärvsarbetande människor i Gävle använder sig av bil och aktiv transport när de transporterar sig till destinationer inom staden. Tio personer, fem butiksbiträden och fem lärare, intervjuades angående deras transportvanor och resonemang kring valet av transportsätt.Resultatet visade att aktiv transport var det vanligaste transportsättet till arbete, träning och butiker i centrum medan bilen var det vanligaste transportsättet till mataffären och destinationer på längre avstånd från hemmet. Avståndet till destinationen, tiden det tar att transportera sig, transport av eventuella varor, bekvämlighet, intresse av motion och rekreation, årstid, väder samt synen på ekonomi och miljö var faktorer som påverkade om deltagarna valde att transportera sig med bil eller aktiv transport. Definitionen på de olika faktorerna varierade mellan deltagarna, vilket kan tyda på att det är den personliga uppfattningen om de olika faktorerna som avgör vilket transportsätt som väljs. Det framkom ingen märkbar skillnad i resvanor mellan deltagare med olika utbildning och arbete.</p>

Quantitative descriptions of reaction kinetics formulated at the stochastic mesoscopic level are frequently used to study various aspects of regulation and control in models of cellular control systems. For this type of systems, numerical simulation offers a variety of challenges caused by the high dimensionality of the problem and the multiscale properties often displayed by the biochemical model. In this thesis I have studied several aspects of stochastic simulation of both well-stirred and spatially heterogenous systems. In the well-stirred case, a hybrid method is proposed that reduces the dimension and stiffness of a model. We also demonstrate how both a high performance implementation and a variance reduction technique based on quasi-Monte Carlo can reduce the computational cost to estimate the probability density of the system. In the spatially dependent case, the use of unstructured, tetrahedral meshes to sample realizations of the stochastic process is proposed. Using such meshes, we then extend the reaction-diffusion framework to incorporate active transport of cellular cargo in a seamless manner. Finally, two multilevel methods for spatial stochastic simulation are considered. One of them is a space-time adaptive method combining exact stochastic, approximate stochastic and macroscopic modeling levels to reduce the simualation cost. The other method blends together mesoscale and microscale simulation methods to locally increase modeling resolution. / eSSENCE

Syftet med denna uppsats var att undersöka vilka faktorer som påverkar hur förvärvsarbetande människor i Gävle använder sig av bil och aktiv transport när de transporterar sig till destinationer inom staden. Tio personer, fem butiksbiträden och fem lärare, intervjuades angående deras transportvanor och resonemang kring valet av transportsätt.Resultatet visade att aktiv transport var det vanligaste transportsättet till arbete, träning och butiker i centrum medan bilen var det vanligaste transportsättet till mataffären och destinationer på längre avstånd från hemmet. Avståndet till destinationen, tiden det tar att transportera sig, transport av eventuella varor, bekvämlighet, intresse av motion och rekreation, årstid, väder samt synen på ekonomi och miljö var faktorer som påverkade om deltagarna valde att transportera sig med bil eller aktiv transport. Definitionen på de olika faktorerna varierade mellan deltagarna, vilket kan tyda på att det är den personliga uppfattningen om de olika faktorerna som avgör vilket transportsätt som väljs. Det framkom ingen märkbar skillnad i resvanor mellan deltagare med olika utbildning och arbete.