There are around 250 glaciers in Sweden, all of which are constantly changing. Knowledge about the bottom topography of glaciers can be used in many different fields and is therefore important to develop.Through ground-penetrating radar data it is possible to calculate ice thicknesses on glaciers, a method that has been used for a long time but is inefficient. At Uppsala University, the glaciology researchgroup is working on developing a new inverse method to find ice thicknesses and bottom topographyon glaciers more easily and less costly. They are testing their method on the Unna and Stour Reiddaglaciers, located in the Kebnekaise masiff just outside Kiruna. The Kebnekaise masiff are part of the Seves Nappes, which was created during the collision of the Laurentia and Baltica continents. The bedrock consists mostly of mafic rocks, but there are parts with varying resistance. This may influence the varying ice thickness. Evidence for overdeepenings in the area is believed to exist, where the glaciers themselves have created bowl-shaped depressions in the bedrock that affect how thick the ice canbecome. Lateral moraines also affect how quickly some parts of the glacier melt. To validate an inverse model method, a map based on radar measurements is needed to compare results. During the survey done in March 2024, radar measurements from the glacier was also taken.These measurements were processed by dewow filtering, normal moveout correction, depth calculations and glacier bottom marking. Based on an interpolation of the processed radar data, a map of the ice thickness of the two glaciers was made. The thickness of Unna Reidda varies from 0 to 123 meters depth and for Stour Reidda from 0 to 147 meters depth. The thickness of the glacier ice was then subtracted from the topography of the mountain to produce the bottom topographic map of the Reidda glaciers. / Det finns som kring 250 stycken glaciärer i Sverige som alla är i ständig förändring. Kunskap om glaciärers bottentopografi kan användas inom många olika fält och är därför viktig att ta fram. Genom markpenetrerande radar data är det möjligt att räkna ut is tjocklekar på glaciärer, en metod som har använts länge men som också är ineffektiv. På Uppsala universitet jobbar Forskargruppen inom glaciologi med att utveckla en ny inversmetod för att enklare och billigare ta reda på is tjocklekar samt bottentopografi på glaciärer. De prövar sin metod på Unna och Stour Reidda glaciärerna som ligger uppe i Kebnekaise-massivet strax utanför Kiruna. Kebnekaise-massivet hör till Seveskållan, som skapades under kollisionen mellan Laurentia och Baltica kontinenterna. Skållan utgörs mestadels av mafiskberggrund men det förkommer delar med varierande hårdhet. Något som eventuellt kan ha en effekt påden varierande is tjockleken. Bevis tros finnas för överfördjupning, där glaciärerna själv skapat skålformade nedbuktningar i berggrunden som påverkar hur tjock isen kan bli. Även laterala morrän påverkar hur snabbt vissa delar av glaciären smälter. För att validera inversmodells metoden behövs en karta baserad på radarmätningar för att jämföra resultat. Under insamling av data i mars 2024 togs även radarmätningar från glaciären. Dessa mätningar processades genom dewow filtrering, Normal Moveout korrektion, uträkningar av djup samt markeringav glaciärernas botten. Utifrån en interpolering av den processade radardata gjordes en karta över istjockleken av de båda glaciärerna. Unna Reidda tjocklek varierar mellan 0 till 123 meters djup och för Stour Reidda från 0 till 147 meters djup. Tjockleken på glaciärisarna drog sedan bort från fjällets topografi för att producera bottentopografisk karta över Reidda glaciärerna

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Desde a década de 90 o fresamento HSM é um processo aplicado na fabricação de moldes e matrizes e, mais especificamente, no acabamento destes componentes. Segundo um levantamento realizado pelo LFS/USP, entre usuários de moldes e matrizes da região de São Paulo, foi confirmada a existência da dispersão da vida de matrizes e moldes. Assim, o objetivo deste trabalho é verificar se esta dispersão está relacionada com os efeitos da usinagem, ou seja, dos parâmetros de corte sobre o desempenho tribológico (vida da matriz). Para isso foi necessário determinar a influência dos parâmetros de corte nas características da integridade da superfície e, por sua vez, como estas características afetam o desempenho. As amostras do aço AISI H13 foram usinadas por fresamento HSM com métodos adotados na fabricação de matrizes e moldes. Os parâmetros de corte investigados foram: velocidade de corte (vc), profundidade de corte (ap), penetração de trabalho (ae) e avanço por dente (fz). As características da integridade da superfície medidas foram: parâmetros de rugosidade pelo método de perfilometria 3D, espessura da camada branca por microscopia óptica e eletrônica de varredura, microdureza da superfície e das subcamadas na seção transversal e tensão residual por difração de raios-x. Após a caracterização, as amostras foram submetidas ao desgaste por deslizamento em um tribômetro na configuração pino-placa com movimento alternado, sob as condições de contorno próximas do forjamento a frio (pressão de contato, material da peça, matriz, velocidade de deslizamento e lubrificante) para posterior correlação com os parâmetros de corte. Nesta etapa, o corpo é a amostra de aço AISI H13 ? 565 HV fresada pela HSM e, o contra-corpo é pino de aço AISI 1020. No âmbito das variáveis investigadas é proposto um modelo capaz de prever o desempenho em função das características topográficas (Str, Sq, índice de formação de cavidades - IFC) e da tensão residual. A camada branca intensamente investigada na literatura não apresentou influência devido a sua formação ocorrer no vale e não nos cumes onde ocorrem os contatos. / Since 90, the HSM milling process to manufacture dies and molds has been applied and, more specifically, in finishing operation those components. In according to LFS/USP survey, among São Paulo region dies and molds users, the dies and molds life dispersion has been confirmed. This dispersion can be related with machining effects on tribological performance and, therefore, on dies and molds life and has not be explained by scientific community yet. Thus, the objective of this work is to verify if this dispersion is related with cutting parameters effects on tribological performance. In order to do it was necessary to determine the cutting parameters influence on surface integrity characteristics and how this characteristic affects the performance. AISI H13 Steel samples were machined by HSM milling by using manufacturing dies and molds methods. The investigated cutting parameters were: cutting speed (vc), cutting depth (ap), working engagement (ae) and feed per tooth (fz). The surface integrity characteristics measured were: roughness parameters by 3D profilometer method, white layer thickness by optical and scanning electronic microscopy, surface and transversal sub-layers section microhardness and residual stresses by x-ray diffraction. Before characterization, the tribometer in pin-plate with alternate movement configuration was performed to sliding wear the samples nearly cold forging conditions, to posterior correlation with cutting parameters. In this stage, the body was the AISI H13? 565 HV steel HSM milling samples and, the counter-body was pin of AISI 1020 steel. In the investigated parameter ambit one model is proposed which is able to predict the performance in topography character functions (Str, Sq, cavity formation index - CFI) and residual stresses. The white layer, which was intensely investigated by other researchers, has no significant influence because its formation occurs in the valley and not at the summits where the contacts occur.

At regional scales climate patterns (e.g., interannual wet-dry cycles) result in high spatial fire synchrony among Southwest forests. However, in the "Sky Island" forests of southeastern Arizona spatial and temporal patterns of fire history and tree age structure at landscape levels (i.e., within mountain ranges) are relatively unknown and therefore the focus of this study. In the Santa Catalina Mountains we reconstructed the fire history on a 2,900-hectare study area with two distinct landscapes, Butterfly Peak (BP) and Rose Canyon (RC) using 2-hectare "points" (i.e., collection areas). The RC landscape was dominated by shallow south-facing aspects and BP was dominated by steep north-facing aspects. Within each landscape, point mean fire intervals (PMFIs) were not significantly different between aspect classes. However, pooled PMFIs were significantly shorter in RC compared to BP. These results show that the fire history at any given point (i.e., 2 hectares or less) was primarily controlled by the broad-scale topography of the encompassing landscape, rather than by the fine-scale topography at that point.Using similar methods we also reconstructed the fire history on Rincon Peak, which is a small isolated mountain range with very step topography. The fire history of the 310-hectare forest area was a mixture of frequent low severity surface fires (from AD 1648 to 1763) and infrequent mixed-severity fires (from AD 1763 to 1867). This mixed-fire regime was probably due to a combination of climatic variability, the small area and rugged topography of this mountain range, and complex fuel arrangements. The distinct fire histories from these two study areas provided natural age structure experiments that indicated tree age cohorts (i.e., higher than expected tree establishment pulses) occurred during periods of reduced fire frequencies. In some instances these periods were likely caused by climatic variability (e.g., a wet and/or cool early 1800s) creating synchronous age cohorts across the region. At other times, extended fire intervals were a function of local topography (e.g., 1763-1819 in the northern half of Rincon Peak). Overall, these studies demonstrated that landscape and climatic variations combine to produce complex spatial and temporal variations in fire history and tree age structures.

A cell’s interaction with its extracellular environment is critical to tissue structure and function. This work investigates the effect of substrate topography on selective cell adhesion and morphology. Alterations in cell response to micro- and nanoscale signals and cues can cause changes in downstream functions of proteins and complexes such as invasive and metastatic motility of malignant tumour cells and the differentiation direction of stem cells. Biomaterial surfaces can be modified to provide different chemical and topographical cues and encourage controlled cell-substrate interaction. At the protein level, template substrates have shown and increased affinity for selective binding of the imprinted antigen or antibody. Topography of a cell’s microenvironment may be replicated as a permanent polymer mould by bioimprinting technology, which was developed at University of Canterbury. The resulting high resolution methacrylate polymer samples have been used for imaging and analysis, but have not previously been investigated as cell culture substrates. This work investigates the effect of bioimprint and photolithographic substrate patterning on cell behaviour in culture. Optimisation of a methacrylate co-polymer resulted in a 6:3:1 ethylene glycol dimethacrylate: methacrylic acid: photoinitiator polymer mixture cured by 240 seconds of UV exposure. The polymer was used to replicate cell membrane features into a permanent polymer mould [a bioimprint]. The resulting high resolution methacrylate bioimprints were cleaned and sterilised for use as a secondary cell culture substrate. Ishikawa endometrial cancer cells were cultured on bioimprinted methacrylate polymer substrates. Preliminary results showed preferential cell adhesion to bioimprinted areas over flat areas and also showed three dimensional spheroid growth instead of lateral two dimensional monolayer spreading. At higher seeding densities, preferential adhesion was similarly noted as well as peeling artefacts of shear stresses and cell size variation on flat methacrylate substrate regions. Fluorescent imaging and cell culture stencilling highlighted the association of secondary cells with bioimprint substrate features. To determine whether preferential cell adhesion effects were due to bioimprint features or general topography modification, secondary cancer cells were cultured on comparable photolithographically-defined, geometrically-patterned substrates. Methods for transferring regular pattern arrays into methacrylate polymer substrates were developed. No organisation or preferential adhesion effects were observed in association with pillar and hole patterns between 5-30 µm. However, artefact incidence in methacrylate polymer replication techniques led to development and adaptation of polystyrene patterning techniques. Experimental analysis of substrate-dependent effects on cell culture adhesion and organisation was extended to a non-cancerous cell line model. C2C12 mouse skeletal muscle cells were chosen for these investigations because of their ability to differentiate further, into myocytes or myofibrils. C2C12 myoblasts seeded on common cell culture substrates showed a notable morphology variation and extent of differentiation between cells grown on tissue culture polystyrene [TCPS] and polydimethylsiloxane [PDMS]. Myoblasts were plated on geometrically-patterned polystyrene and PDMS substrates. Significant alignment to grated pattern features was observed on both substrate types, before and after driven differentiation. Peeling artefacts of confluent tissue-like culture from PDMS surfaces which were observed were unreported previously in literature. The results reported in this thesis provide a foundation for potential research and commercial application for surface modification methods. The biomimetic topography provided by bioimprinted substrates can be used to identify and investigate cell activities, including for example the mechanisms of cell adhesion and separation in metastatic and invasive cancer research. Altering the material of the bioimprinted substrates may attune substrate topographies as scaffolds to direct specific stem cell differentiation for regenerative tissue engineering applications.

A tree-ring scanning densitometer and data acquisition system has been built by the Geological Survey of Canada to extract tree-ring density and tree-ring width data from dendrochronological specimens and X-ray negatives of specimens. The system produces tree-ring density plots, ring density and ring-width bar graphs, and printed and punch tape digital data. This prototype was built primarily from commercial pre-constructed electronic components, but a modified densitometer and other original-design units also were used in the construction.

The general trend in gear industry is an increased focus on gear transmission efficiency. This thesis focuses on the understanding of how different gear manufacturing methods – particularly the contribution of the running-in process – affect the surface characteristics and friction response, with the purpose of increasing gearbox efficiency. The thesis consists of a summary and five appended papers. The research hypothesis in paper A and paper B was that the dry elastic contact area ratio is a descriptive parameter for the contact condition. Paper A deals with the influence of manufacturing method on the initial contact conditions. The emphasis in paper B is the changes that occur during running-in and correlating these changes to design requirements. Paper C examines the influence of manganese phosphate coating and lubricants, with respect to friction and the risk of scuffing at the initial contact. Paper D examines the effect of running-in load on the friction response for different surfaces. In paper E, the question of whether the load during running-in influences the gear mesh efficiency is further expounded. The main conclusions of this thesis are that the running-in influences the gear mesh efficiency; a high running-in load enhances the gear mesh efficiency. The difference in mesh efficiency is in the range of one tenth of a per cent. Thus, the influence of running-in cannot be neglected because it is in the same order of magnitude as reported for other gear efficiency enhancements. Furthermore, the dry elastic contact area ratio presents a descriptive measure of how surface topography influences the contact, at both a global (form deviation) and local (roughness) level. The surface topography caused by the manufacturing method has a significant influence on the contact area ratio. Shaving was found to have the highest contact area ratio, and would therefore be the best choice if deviations from case hardening could be minimised. It was also confirmed that surfaces coated with manganese phosphate raise the limiting load for scuffing failure up to 13 times compared to the uncoated ground equivalent. / <p>QC 20141002</p>

This is a creative/critical project, a collection of narratives inspired by critical discourse that map a local landscape and chart a personal topography. As a result of interdisciplinary study, particularly in the area of cultural geography and map making, I found new ways to explore ideas about Cornwall’s heritage, her undermined landscape and expand upon issues raised in my MA dissertation. Recognising the instability and partiality of maps provided insight and mapping became method as newly revealed pathways and subtly shifting perspectives inspired fresh narratives which challenge stereotypical images of Cornwall and reveal the sometimes dark realities of rurality. The more personal narratives in this collection reveal a different undermined landscape: ideas about romantic constructions and inheritance led to explorations of nostalgia, memory and identity. Life events became life writing and many of these narratives reflect a search for direction and for a missing person: the artist I once was. But there are other disappearances in these narratives and the final chapter gives an account of family events that had to be recorded but which raise ethical questions that life writers cannot ignore. We must take responsibility for the way we write about vulnerable subjects and recognise what this writing tells us about ourselves: that, as Nancy K. Miller has suggested, by exposing our lives to others through life writing, we too become vulnerable subjects. The essay accompanying these narratives reflects upon process and finds ways of giving an account of the writer writing. It uncovers contemporary theories that are embedded in the narratives and I describe it as an orouboros, a creature that continuously eats its own tail. Like the text it subjects to scrutiny, the essay is a life narrative, an autobiographical act that merges creative and critical thinking and this amalgamation has been my aim since my studies began.

The cornea is the anterior most surface of the eye and plays a critical role in vision. A thin fluid layer, the tear film, coats the outer surface of the cornea and serves to protect, nourish, and lubricate the cornea. At the same time, the tear film is responsible for creating a smooth continuous surface, where the majority of refraction takes place in the eye. A significant component of vision quality is determined by the shape of the cornea and stability of the tear film. A dual interferometer system for measuring the dynamic corneal topography is designed, built, verified, and qualified by testing on human subjects. The system consists of two coaligned simultaneous phase-shifting polarization-splitting Twyman-Green interferometers. The primary interferometer measures the surface of the tear film while the secondary interferometer tracks the absolute position of the cornea, which provides enough information to reconstruct the absolute shape of the cornea. The results are high-resolution and high-accuracy surface topography measurements of the in vivo tear film and cornea that are captured at standard camera frame rates. (C) 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)