Walking and well-being: landscape, affect, rhythm

This thesis is an ethnographic exploration of group walking practices in the Hampshire countryside, investigating the embodied, affective and social practice of the shared walk and its relation to the individual pursuit of wellness. Responding to the growing literature in qualitative health geography using ‘therapeutic landscape’ as a conceptual framework, group walking practices are approached in this thesis from a perspective of more-than-representational theories of social practice that aims to address group dynamics and the role of social relations for the establishment of therapeutic spaces. While also drawing attention to the embodied and affective nature of experience, this thesis opens a discussion between health geography and cultural geographies on the issues of the body, mobility and collective experience. Further, the thesis aims to place the study findings within the wider cultural phenomena of ‘walking for health’ through an exploration of practices of assemblage. Deleuzian assemblage theory, both as a pragmatic analytical tool and an ontological position, offers a new approach to thinking health and place relationally, arguing for a distribution of agencies and providing a framework for tracing their emergent effects across complex networks.The thesis finds its empirical focus in ethnographic fieldwork with five walking groups as well as individual mobile interviews. The findings discussed in the thesis firstly pertain to the significance of social relations for well-being, exploring the kinds of socialities that are produced while walking together, and arguing that the shared walk has the potential to establish a place-specific social aesthetic that can be experienced as restorative. Secondly, the rural walkscape as a therapeutic landscape is analysed as a specific outcome of place-based rhythms, implicated in the performativity and mobility of the body in the creation of a restorative place/practice. It is found that the shared walk is characterised by specific rhythmic qualities and that walking as a health practice is subject to a range of norms, regulations and performative styles.The findings and conceptual development in this thesis contribute to an interrogation of the complex processes through which therapeutic landscapes are established, practiced and experienced. The thesis also contributes to more-than representational geographies of embodiment, affect and landscape, which are intimately tied up in the production and performance of both wellness and place

The photochemistry of uranium hexafluoride as applied to laser isotope separation

The subject of this dissertation is the very relevant field of laser instigated photochemistry. Its application to the industrially important process of uranium separation is carefully studied and reported. The isotope separation is accomplished by selectively vibrationally exciting the minor isotope, 235U, with an infrared laser. Subsequently, adequate laser energy of another infrared laser/s is coupled to the UF 6 molecule which causes bond rupture. The photochemistry of this laser based process will determine its economical viability. At the onset of this study very scant knowledge about the photochemistry of the uranium hexafluoride molecule was available in the scientific literature and important phenomena were unexplained. Many of these were clarified and explained during the course of this investigation. Furthermore, many previously assumed and accepted aspects concerning the photochemistry of uranium hexafluoride were proven to be incorrect or unsubstantiated. Firstly, the laser instigated unimolecular dissociation rate of UF6 was calibrated with experimental data. The RRKM statistical theory was employed to correctly describe the unimolecular dissociation process. Excellent agreement between theory predictions and experimental thermal dissociation data was obtained. This verifies the chosen geometrical configuration of the activated complex as proper and reasonable. A simple bond rupture reaction, where the activated complex is represented by a weak bonding of the UF 5 moiety to a fluorine atom, seems appropriate. In establishing the features of the activated complex, the vibrational frequencies of the UF5 molecule were allocated to the transition configuration together with two hindered rotations. The U-F bond that is ruptured, is stretched to three times the equilibrium bond length in the activated complex. The well known Whitten Rabinovitch approximation to determine the density of the vibrational states was employed but a less cumbersome formulation for UF 6 was subsequently derived. This methodology was for the first time applied to UF6 with very good results. Previous two efforts, reported in the scientific literature, were unsuccessful in the sense that agreement between theory and experimental observations was poor. This treatise shows that the unimolecular dissociation rate for UF6 is at least two orders faster than previously advocated. This impacts very positively on the entire separation process. The influence of molecular collisions and the quenching effect this has on the unimolecular dissociation rate must normally be taken cognisance off. In chapter III the transfer of vibrational energy between UF 6 molecules is studied with the aid of a pump and probe experiment. When a hydrogen containing molecule like CH4 is present in the gas mixture, strong HF fluorescence is detected when the F radical reacts with the former. This can be utilized to measure the transfer rate of vibrational energy. It was established that very fast transfer occurs when CH4 is present and also the transfer mechanism between UF 6 molecules was identified to be of a long range nature. It is proposed that a dipole-dipole mechanism for vibrational energy exchange is operative. This seems to be confirmed by the inverse temperature dependence with the rate measured. This is in contrast to the hard sphere gas kinetic theory which predicts a direct dependence with temperature. In the final instance, however, the measured transfer rates are still much slower than the unimolecular dissociation rates of UF 6 determined in chapter III and its contribution can consequently be neglected at the envisaged gas density. Much effort was expended during this study to experimentally measure the unimolecular dissociation rate of UF 6, after laser excitation, inside a molecular beam apparatus. The measurement technique that is suitable for such an application is the mass spectrometry. However, the requirements to measure in the corrosive environment of UF6 as well as the very fast time resolution needed, posed terrific challenges. Various ionization techniques to ionize UF6 and its photo product were developed and tested. A commercial quadrupole mass spectrometer as well as a locally built time-of-flight mass spectrometer was utilized for the detection of ion fragments. It was established that the formation of negative molecular UF 6 ions in a pulsed mode represents the best solution to the requirements. Nevertheless, the actual rates could not be measured due to the demise of the MLIS project. The success of accurately modelling the thermal unimolecular dissociation of UF 6 , to a large degree compensated for this disappointment. In the last chapter, the secondary reactions following on the unimolecular dissociation of UF 6, are reported and scrutinized. This section represents a major overhaul of the established picture that prevailed up to this study. At least nineteen different conclusions, stemming from experimental observations, are put forward. Each of these differs profoundly from previously held views on the secondary reactions following laser photolysis of UF 6 • Amongst the more prominent findings are: 1. The presence of the uranium compound, UF 4, in the laser photolysis products of UF 6 has unambiguously been established. This is true for both infrared and ultraviolet laser photolysis. 2. The internal energy content of nascent photolysis products is extremely important to determine the secondary reactions. Equally important is the rate of internal energy loss in various environments to promote or inhibit reactions. 3. There is a great danger in equating the results of static gas cell irradiations, i.e., repeated laser shots, with the photolysis results in dynamic systems. This has previously led to incorrect interpretations.Thesis (DPhil (Science))--University of Pretoria, 1998.ChemistryDPhil (Science)Unrestricte

The physicochemical characterisation of pepsin degraded pig gastric mucin

Mucins are the main macromolecular components of the mucus secretions that cover the oral cavity, gastrointestinal and urogenital tracts of animals. The properties of the mucus secretions are therefore directly correlated with the physicochemical properties of mucin glycoproteins. In this study, mucins were obtained from pig gastric mucous after digestion with pepsin at 37 ⁰C for 4 hours, these mucins were characterised in terms of compositional and hydrodynamic properties. Compositional analysis showed that this mucin contains protein (15%), carbohydrates (55%) of which the constituents are: fucose (4%), galactose (9%), glucosamine (55%), glucosamine (33%) and sialic acid (2%). The latter component gives the mucin polymer a pH-dependant negative charge, with a -potential of -3 mV at pH 1.2 up to -11 mV at pH 7.4. The weight average molar mass was ~1 x 106 g/mol and intrinsic viscosity was ~0.42 dL/g although there was a small pH dependency due to the polyelectrolyte behaviour of the polymer. The measurements of viscosity versus shear rate showed shear thinning behaviour and the critical overlap concentration was determined to be 10-11% w/v indicating a compact structure. Knowledge of these properties is fundamental to the understanding interactions of mucins, with for example, novel drug delivery systems

Surface Co-Expression of Two Different PfEMP1 Antigens on Single Plasmodium falciparum-Infected Erythrocytes Facilitates Binding to ICAM1 and PECAM1

The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) antigens play a major role in cytoadhesion of infected erythrocytes (IE), antigenic variation, and immunity to malaria. The current consensus on control of variant surface antigen expression is that only one PfEMP1 encoded by one var gene is expressed per cell at a time. We measured var mRNA transcript levels by real-time Q-PCR, analysed var gene transcripts by single-cell FISH and directly compared these with PfEMP1 antigen surface expression and cytoadhesion in three different antibody-selected P. falciparum 3D7 sub-lines using live confocal microscopy, flow cytometry and in vitro adhesion assays. We found that one selected parasite sub-line simultaneously expressed two different var genes as surface antigens, on single IE. Importantly, and of physiological relevance to adhesion and malaria pathogenesis, this parasite sub-line was found to bind both CD31/PECAM1 and CD54/ICAM1 and to adhere twice as efficiently to human endothelial cells, compared to infected cells having only one PfEMP1 variant on the surface. These new results on PfEMP1 antigen expression indicate that a re-evaluation of the molecular mechanisms involved in P. falciparum adhesion and of the accepted paradigm of absolutely mutually exclusive var gene transcription is required

Panel 6 : Vaccines

Objective. To review the literature on progress regarding (1) effectiveness of vaccines for prevention of otitis media (OM) and (2) development of vaccine antigens for OM bacterial and viral pathogens. Data Sources. PubMed database of the National Library of Science. Review Methods. We performed literature searches in PubMed for OM pathogens and candidate vaccine antigens, and we restricted the searches to articles in English that were published between July 2011 and June 2015. Panel members reviewed literature in their area of expertise. Conclusions. Pneumococcal conjugate vaccines (PCVs) are somewhat effective for the prevention of pneumococcal OM, recurrent OM, OM visits, and tympanostomy tube insertions. Widespread use of PCVs has been associated with shifts in pneumococcal serotypes and bacterial pathogens associated with OM, diminishing PCV effectiveness against AOM. The 10-valent pneumococcal vaccine containing Haemophilus influenzae protein D (PHiD-CV) is effective for pneumococcal OM, but results from studies describing the potential impact on OM due to H influenzae have been inconsistent. Progress in vaccine development for H influenzae, Moraxella catarrhalis, and OM-associated respiratory viruses has been limited. Additional research is needed to extend vaccine protection to additional pneumococcal serotypes and other otopathogens. There are likely to be licensure challenges for protein-based vaccines, and data on correlates of protection for OM vaccine antigens are urgently needed. Implications for Practice. OM continues to be a significant health care burden globally. Prevention is preferable to treatment, and vaccine development remains an important goal. As a polymicrobial disease, OM poses significant but not insurmountable challenges for vaccine development.Peer reviewe

A description and phylogenetic relationship of a polycotylid plesiosaur (Reptilia: Sauropterygia) from the Upper Cretaceous (Turonian) of Goulmima, Morocco

A Moroccan polycotylid plesiosaur from the early Turonian (Upper Cretaceous) of the Goulmima Formation is described. The specimen, bought from an American fossil dealer in 2002 by the Museum of Natural History, Oslo, is a nearly complete skull of an unknown species. It is compared to the holotypes of Thililua longicollis Bardet et al. 2003 and Manemergus anguirostris Buchy et al. 2005, both from the same formation, to investigate the phylogenetic relationship between the three specimens. A phylogenetic analysis and ordinance tests suggest that they are very closely related; still they display enough important morphological differences to signify that the Oslo specimen is different enough from the two other species to warrant a further investigation and description as a new species

LEAN - En kulturell förändring

Bakgrund och problem: Lean är ett begrepp som på senare tid har blivit alltmer välkänt, men många gånger felkänt. Vi upplever svenska företag som duktiga på effektivitet vad gäller de finansiella aspekterna men inte fullt lika duktiga på den organisatoriska effektiviteten. De tidigare studier vi har tagit del av som behandlar begreppet lean, upplever vi ej ge en tillräcklig redogörelse för konceptet lean och dess ursprung. De två företagen som vi har valt att studera i denna uppsats verkar i olika branscher. Det ena företaget är ett service- och tjänsteföretag som tillhandahåller heltäckande tjänster inom resebranschen riktade till slutkonsument. Det andra företaget är ett klassiskt tillverkande företag med inriktning mot hydraulik, pneumatik och filtrering där majoriteten av kunderna utgörs av andra större företag. Problem: Hur kan företag arbeta med lean för att konceptet ska få bästa möjliga organisatoriska verkan? Syfte: Syftet med vår studie är att beskriva begreppet lean och hur det uppfattas av våra två valda företag. Studien ska även behandla olika implementeringsförfaranden och visa eventuella resultat lean kan ge upphov till. Vidare är vår förhoppning att utifrån fallstudierna kunna skönja tecken som är viktiga att ta i beaktande vid implementering av lean. Metod: Sex stycken djupintervjuer gjordes med personer i ledande positioner i de valda företagen. Dessa har varit delaktiga i beslutsprocessen vid införandet av lean. Fortsättningsvis har empirin analyserats utifrån en teoretisk referensram som behandlar leans bakgrund, implementering av lean, kulturell förändring samt kritik mot lean. Resultat och slutsats: Lean tanke- och arbetssätt är ett debatterat ämne, med många förespråkare både för och emot. Valet att börja arbeta utifrån leanprinciperna anser vi måste vila på en förståelse för vad lean innebär samt vara ödmjuk inför den stora förändringsprocess som detta kommer att medföra. Om ledningen är medveten om lean och är beredda att satsa på konceptet samt att med uthållighet och ihärdighet fullfölja resan och agera lean, anser vi att lean tanke- och arbetssätt kan vara en mycket kraftfull filosofi att grunda ett företag på. Förslag till fortsatt forskning: Då denna studie utgick från ett ledningsperspektiv anser vi det vara mycket intressant att göra en liknande studie, men då se till de anställdas situation och hur de upplever vardagen i ett lean företag. Vidare anser vi att det skulle vara av stor vikt med fler studier som berör lean i tjänste- och servicesektorn. Avslutningsvis kan det även vara mycket intressant att göra en uppföljning på våra studerade företag i framtiden, för att se hur de kommit vidare i sitt arbete med lea

n Elektronmikroskopiese studie van oksidasieverskynsels en bundelverhitting by Al-Mg allooie

Proefskrif (M. Sc.) -- Universiteit van Stellenbosch, 1974.Full text to be digitised and attached to bibliographic record

Crystallographic properties and oxidation-influenced kinetics of secondary defects in quenched aluminium and aluminium-alloys

Thesis (Ph. D.) -- University of Stellenbosch, 1976.Full text to be digitised and attached to bibliographic record