Atmospheric aerosols have been shown to have a significant impact on air quality and health in urban environments. Organic aerosols (OA) are one of the main constituents of submicron particulate matter. They are composed of thousands of different chemical species, which makes it challenging to identify and quantify their sources. OA sources have been previously studied; however quantitative knowledge of aerosol composition and their processes in urban environments is still limited. The results presented here investigate OA, their chemical composition and sources as well as their interaction with gases. On-line measurements of species in the particle and the gas phase were performed both from field-based and laboratory studies. Aerosol Mass Spectrometers (AMS) were used together with the Chemical Ionisation Mass Spectrometer (CIMS) and the Filter Inlet for Gases and AEROsols (FIGAERO). Two ambient datasets were analysed to develop methods for source apportionment, using the Multilinear Engine (ME-2), in order to gain new insights into aerosol sources in Manchester and London. Long-term measurements in London allowed the opportunity to perform seasonal analysis of OA sources and look into the relationship of hydrogen-like OA (HOA) and heavy- and light-duty diesel emissions. The seasonal analysis provided information about OA sources that was not possible to observe on the long-term analysis. During Bonfire Night in Manchester, with high aerosol concentrations, particularly biomass burning OA (BBOA), it was possible to identify particulate organic oxides of nitrogen (PON), with further identification of primary and secondary PON and their light absorbing properties. Through laboratory work, new insights into cooking organic aerosols (COA) were gained, a higher relative ion efficiency (RIEOA) value of around 3.3 for OA-AMS compared with the typical RIEOA of 1.4 was determined, which implies COA concentrations are overestimated when using the RIEOA value of 1.4. Dilution showed to have a significant effect on food cooking experiments, increasing both the gas/particle ratios and the O:C ratios. The data generated in this work, OA-AMS mass spectra and markers from both gas and particle phase identified with FIGAERO-CIMS, provide significant information that will contribute to the improvement of source apportionment in future studies. This work investigates OA, with a focus on primary organic aerosols originated from anthropogenic activities. These scientific findings increase our understanding of OA sources and can help to improve inventories and models as well as to develop plans and policies to mitigate the air pollution in urban environments.

Introduction: Nitric oxide (NO) is an integral molecule implicated in the control of vascular function. It has been suggested that vascular dysfunction may lead to the development of acute mountain sickness (AMS), high-altitude cerebral oedema (HACE) and high-altitude pulmonary oedema (HAPE), though data to date remains scarce. Therefore, there is a clear need for further work to address the role of NO in the pathogenesis of high-altitude illness. Aims: There were two primary aims of the current work: (1) To examine whether hypoxia mediated changes in systemic NO metabolism are related to the development of AMS and sub-clinical pulmonary oedema and (2) to examine whether hypoxia mediated changes in the trans-cerebral exchange kinetics of NO metabolites are related to the development of AMS and headache. Hypothesis: We hypothesise that hypoxia will be associated with an increase in reactive oxygen species (ROS) formation, resulting in a decrease in vascular NO bioavailability (O2•- + NO → ONOO•-, k = 109 M.s-1). The reduction in NO will lead to vascular dysfunction and impaired oxygen (O2) delivery. Subsequent hypoxaemia will result in pulmonary vascular vasoconstriction and the development of sub-clinical pulmonary oedema within and mild brain swelling. Symptoms and reductions in NO bioavailability will be more pronounced in those who develop AMS since they are typically more hypoxaemic. Alternatively, a hypoxia mediated increase in NO, during vasodilatation, specifically across the cerebral circulation, may activate the trigminovascular system resulting in headache and by consequence, AMS. Methods: Study 1 – AMS symptoms, systemic venous NO concentration and nasal potential difference (NPD), used as a surrogate biomarker of extravascular lung oedema, were quantified in normoxia, after a 6hr passive exposure to 12% oxygen (O2) and immediately following a hypoxic maximal exercise challenge (≈6.5 hrs). Final measurements were 2 obtained two hours into (hypoxic) recovery. Study 2 – AMS, radial arterial and internal jugular venous NO metabolite concentrations and global cerebral blood flow (CBF), using the Kety-Schmidt technique, were assessed in normoxia and after a 9hr passive exposure to 12.9% O2. AMS was diagnosed if subjects presented with a combined Lake Louise score of ≥5 points and an Environmental Symptoms Questionnaire – Cerebral score of ≥0.7 points. Results: Hypoxia was associated with a reduction in total plasma NO, primarily due to a reduction in nitrate (NO3•) and a compensatory increase in red blood cell (RBC)-bound NO(P < 0.05 vs. normoxia) in both studies. Study 1 – Exercise reduced plasma nitrite (NO2•) (P< 0.05 vs. normoxia) whereas RBC-bound NO did not change. NO was not different in those who developed AMS (AMS+) compared to those who remained comparatively more healthy (AMS-) (P < 0.05). NPD was not affected by hypoxia or exercise and was not different between AMS+ and AMS- (P > 0.05). Study 2 – Hypoxia decreased arterial concentration of total plasma NO due primarily to a reduction in NO2•- and nitrate (NO3•-). Hypoxia did not alter the cerebral metabolism of RSNO, whereas the formation of RBC-bound NO increased. Discussion: These findings suggest that alterations in systemic or trans-cerebral NO metabolism are not implicated in the pathophysiology of AMS or sub-clinical pulmonary oedema. However, hypoxia was associated with an overall reduction in the total NO pool (NOx), whereas, selected alterations in more vasoactive NO metabolites were observed. Reductions in the partial pressure of O2 (pO2) were thought to be a key regulator in these changes. Overall net increases in RBC NO and corresponding reductions in plasma NO2• in the face of no alterations in NOx indicates that rather than being simply consumed, NO is reapportioned to other NO metabolites and this may be implicated in the pathophysiology of AMS.

For emergency service providers, giving their service in least time shows their best performance. Emergency hospitals will be at their best if the ambulance reaches the site in Golden hour where life of injured persons can be saved. Ambulance uses the road network to reach the accident site. Today there are many GIS based systems being developed for routing of ambulance using GPS and other real-time technologies. These systems are useful and play a major role in solving the routing problem. But now roads are so congested that it difficult for the Ambulance drivers to travel and reach the accident. In this thesis present study area is studied and problems faced by emergency service providers on road network are identified. In this thesis GIS/GPS/GSM based prototype system has been developed for routing of ambulance on road network of Hyderabad city (AMS). This prototype is designed such that it finds the accident location on the road network and locates the nearest ambulance to incident site using the real-time technologies (GPS/GSM). AMS creates the fastest route from nearest ambulance to accident site, and from there to nearest hospital. Congestion on roads during peak hours is considered, and the fastest route on both major and minor roads is created. In this thesis AMS user interface has been developed using VBA, ArcGIS (network analyst). This Ambulance management system has been developed using software engineering model rapid prototyping model and has been evaluated by GIS users

Des analyses structurales et pétrophysiques ont été menées dans le Massif de Melechov afin d’étudier les structures contrôlant la porosité, la perméabilité et la conductivité thermique de la roche. La structure du massif a été déterminée sur la base d’un jeu étendu de données incluant des mesures d’ASM et des mesures de terrain des structures ductiles et cassantes. Le système de fractures du massif a été décrit par quatre ensembles de fractures. Les données pétrophysiques mesurées ont servi pour caractériser l’effet de la fracturation et de l’altération sur la géométrie de l’espace poreux et en conséquence sur la perméabilité, la conductivité thermique et les propriétés élastiques du granite. Des propriétés pétrophysiques distinctes ont été identifiées pour du granite intact, du granite sain fracturé ainsi que pour du granite fracturé et altéré contenant des oxydes de fer, de la chlorite et des minéraux argileux. Une étude microstructurale détaillée, combinée à des mesures multi-directionnelles de vitesse des ondes P (VP) à pressions de confinement croissantes a été menée sur un échantillon du granite Lipnice aux schlieren. Les résultats indiquent que l’anisotropie des VP à basses pressions de confinement est contrôlée par des fissures inter-granulaires reliant les clivages sous-parallèles aux schlieren des micas et des feldspaths ainsi que par des fissures intra- ou trans-granulaires dans du quartz sous-parallèles aux fractures d’exfoliation. Une importante fermeture de la porosité de fissures à partir d’une profondeur de 500 m a été interprétée en termes d’élasticité des fissures manifestée par une augmentation rapide des VP avec la pression de confinement croissante. / Structural and petrophysical analysis have been conducted within the Melechov massif with focus on structures controlling the porosity, permeability and thermal conductivity of the rock. The structure of the massif has been constrained based on extensive dataset including AMS and field structural measurements of ductile and brittle structures. The fracture system of the massif has been described by four sets of fractures. The measured petrophysical data have been used to characterize the effect of fracturing and alteration on pore space geometry and in turn on permeability, thermal conductivity and elastic properties of the studied granite. Distinct petrophysical properties have been identified for pristine granite, for fractured fresh granite as well as for fractured granite altered by Fe-oxide, chlorite and clay minerals. A detailed microstructural study combined with multidirectional P-wave velocity measurements at high confining pressure and with AMS analysis has been conducted on a schlieren bearing sample of Lipnice granite. The granite VP anisotropy at low confining pressure was controlled by intergranular cracks interconnecting schlieren-subparallel cleavage cracks in micas and feldspars and by exfoliation fracture-subparallel intra- or trans-granular cracks in cleavage-free quartz. Major closing of the crack porosity linked to the schlieren granite below depth of 500 m has been interpreted in terms of crack compliance reflected by rapid increase in VP with confining pressure.

Sacrificial metallic coatings have been used in the past, for protecting steel in industrial and urban developments. It has been suggested that thermally sprayed aluminium coatings, immersed in marine environments, are also capable of protecting steel by providing galvanic protection. Researchers have also speculated that the growth of inert oxide products, on top of the coating as well as inside pores and cracks, could enhance even further its protective “shielding” properties. In addition, the self-healing abilities of the coatings, in case of mechanically induce damage, are still a matter of debate. This research project takes a critical look at these assumptions, focusing on the electrochemical response of aluminium metal sprayed (AMS) coatings immersed in 0.6 M NaCl and 0.6 M Na2SO4 solutions, in order to investigate how the presence of chlorides can alter the corrosion behaviour of these coatings. For such, a thin aluminium protective coating was deposited over two different panels (aluminium 1050 and low carbon steel), by the steel making company Fairfield-Mabey, using electric arc thermal spraying (TS). Subsequently, the coated panels were sectioned into smaller specimens, and with the aid of a SEM/EDS, and XRD, observations and analysis were conducted in their surfaces and cross sections, in order to determine the morphology, quality of deposition, and chemical composition of the coatings. Internal porosity/oxide growth after immersion, was studied using 3-D X-ray tomography scanning. Furthermore, the electrochemical behaviour of the coatings (intact and scribed) was also investigated, initially by analyzing the evolution of the open circuit potential in time, when immersed in chloride rich and chloride free environments. Additionally, the anodic polarization behaviour of the substrate and coatings were simultaneously analyzed, by connecting a zero resistance ammeter (ZRA) with the W.E. terminal of a potentiostat. To conclude, EIS and Rp vs. time plots were made in order to corroborate the data obtained from other tests. Results show that although the coating can generate superficial and internal corrosion products, these oxides are not isolating in nature nor will enhance its protective properties. On the other hand, the corrosion potential behaviour of the coatings revealed that AMS coatings have a more active than the substrate; regardless of the environment in which they were immersed or their substrate. Nevertheless, it was also observed that AMS coatings deposited onto steel will corrode faster than their substrates, and for that matter capable of offering corrosion protection, exclusively if chlorides are present in the solution.

The objective of this thesis was to reconstruct the Sedimentary, Cryostratigraphic and Paleoclimatic history of Two Moose Lake, central Yukon using a new analytical technique for dating ice wedges using Dissolved Organic Carbon (DOC). During two field seasons in August 2013 and April 2014, 442 samples were collected from a newly exposed headwall of a thaw slump with 7 ice wedges and over 4m of sediment. Using cryostratigraphy, granulometry, stable isotopes and 18 14C-DOC ages, 4 stratigraphic units were delineated: 1) a sediment-rich ice layer inferred to be of glacial origin (>32ka BP); 2) a silt-rich layer deposited during the Holocene Thermal Maximum (~10 to 8.2ka BP); 3) a silt with organics layer deposited from ~8ka to 6.4ka BP, and 4) a paleo-active layer and modern active layer. 14C-DOC dating indicated two periods of ice wedge activity at Two Moose Lake, the first during the late Pleistocene (31,608 to 12,990 yr cal BP) and from the mid-Holocene to present (6,328 to 892 yr cal BP). The presence of late-Pleistocene aged ice wedges at Two Moose Lake supports the common belief of an unglaciated central Yukon during the most recent McConnell glaciation from 29.6 to 13ka BP. Values for δ18O from the Holocene- and Pleistocene-aged ice wedges were 2-3‰ and 5-9‰ depleted compared those of modern precipitation from Mayo (-22.32‰). Medium-resolution (2-4cm) sampling along with multiple 14C-DOC samples along a transect allowed for the creation of a continuous δ18O and temperature age profile to be developed from multiple ice wedges, showing a strong consistency between overlapping ages. The reconstruction of the paleoclimate of Two Moose lake is consistent with known events from southern Yukon including the Boutellier Inderstadial, a cold unglaciated central Yukon during the McConnell Glaciation, warming during the Holocene Thermal Maximum (HTM) followed by an extreme cooling event at 8.2ka BP, a cooling event at 4.2ka BP, and the subsequent warming to present temperatures.

Applying the anisotropy of magnetic susceptibility to analogue models provides detailed insights into the strain distribution and quantification of deformation within contractional tectonic settings like fold-and-thrust belts (FTBs). Shortening in FTBs is accommodated by layer-parallel shortening, folding, and thrusting. The models in this research reflect the different deformation processes and the resulting magnetic fabric can be attributed to thrusting, folding and layer-parallel shortening. Thrusting develops a magnetic foliation parallel to the thrust surface, whereas folding and penetrative strain develop a magnetic lineation perpendicular to the shorting direction but parallel to the bedding. These fabric types can be observed in the first model of this study, which simulated a FTB shortened above two adjacent décollements with different frictional properties. The different friction coefficients along the décollements have not only an effect on the geometric and kinematic evolution of a FTB, but also on the strain distribution and magnitude of strain within the belt.  The second series of models performed in this study show the development of a thrust imbricate and the strain distribution across a single imbricate in more detail. Three models, with similar setup but different magnitudes of bulk shortening, show strain gradients by gradual changes in principal axes orientations and decrease in degree of anisotropy with decreasing distance to thrusts and kinkzones. These models show that at the beginning of shortening, strain is accommodated mainly by penetrative strain. With further shortening, formation of thrusts and kinkzones overprint the magnetic fabric locally and the degree of anisotropy is decreasing within the deformation zones. At thrusts, an overprint of the magnetic fabric prior deformation towards a magnetic foliation parallel to the thrust surfaces can be observed. A rather complex interplay between thrusting and folding can be analysed in the kinkzones. In general, this thesis outlines the characteristics of magnetic fabric observed in FTBs, relates different types of magnetic fabric to different processes of deformation and provides insights into the strain distribution of FTBs.

Structural and petrophysical analysis have been conducted within the Melechov massif with focus on structures controlling the porosity, permeability and thermal conductivity of the rock. The structure of the massif has been constrained based on extensive dataset including AMS and field structural measurements of ductile and brittle structures. Maps and stereograms have been constructed to display the magnetic fabrics and the fracture system of the studied massif. The fracture system of the massif has been described by two principal and two supplementary sets of joints and by faults formed mainly by joint reactivation or less frequently formed as shear fractures. The measured petrophysical data have been used to characterize the effect of fracturing and alteration on pore space geometry and in turn on permeability, thermal conductivity and elastic properties of the studied granite. Distinct petrophysical properties have been identified for pristine granite, for fractured fresh granite as well as for fractured granite altered by Fe-oxide, chlorite and clay minerals. Relations between the measured petrophysical properties have been explained in terms of evolution of the rock pore space. A detailed microstructural study combined with multidirectional P-wave velocity measurements at high confining pressure and...

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A set of vertices in a graph G is a global dominating set of G if it dominates both G and its complement G. The minimum cardinality of a global dominating set of G is the global domination number of G. We explore the effects of graph modifications (edge removal, vertex removal, and edge addition) on the global domination number. In particular, for each graph modification, we study the global domination stable trees, that is, the trees whose global domination number remains the same upon the modification. We characterize these stable trees having small global domination numbers.