Høye poretrykk utgjør en risiko for boreoperasjoner på Norsk Sokkel og internasjonalt. Denne risikoen kan reduseres dersom man har kjennskap til poretrykksforholdene før boring. Poretrykk er også en viktig parameter for felt i produksjon, og kunnskap om hvordan dette utvikler seg over tid vil kunne ha stor betydning for økt oljeutvinning. Seismiske data inneholder informasjon om poretrykket og kan derfor bidra til økt kunnskap på dette området. Avhandlingen tar for seg hvordan hastighets- og amplitudeinformasjon fra seismiske data kan brukes for å estimere poretrykk. / Abnormally high pore pressures in the subsurface pose a hazard to drilling operations worldwide. The problem is not unusual on the Norwegian Continental Shelf. Knowledge of the pore pressure prior to drilling may reduce the risk related to drilling in high pressure zones. Pore pressure is also a vital paramter for producinig fields, and knowledge of how the pressure develops over time can be important for increased oil recovery. Seismic data contain information on the pore pressure and may contribute to increased understanding of subsurface pressure conditions. The thesis deals with methods for estimation of pressure from seismic velocity and amplitude data.

Higher plants cannot move to a more favorable place when the environmental conditions are changing. To adapt to changes in light, temperature and access to water the plants had to evolve special mechanisms at the molecular level. Post-translational modifications of proteins, like phosphorylation, often serve as “on-and-off” switches in regulation of cellular activity and may affect protein-protein interactions. Photosynthesis in higher plants is regulated by reversible protein phosphorylation events, in a unique light- and redox-controlled system. Several biochemical methods are effectively used for characterization of phosphorylated proteins in photosynthetic membranes. Nevertheless, mass spectrometry is the most effective technique when it comes to identification of exact phosphorylation site(s) in the protein sequence, which is the ultimate evidence of protein phosphorylation. The same tandem mass spectrometry analysis identifies other in vivo post-translational modifications as well, such as acetylation of the N-terminus of mature protein. To study membrane proteins is a challenging project. In the present work the “shaving” of surface-exposed part of the membrane proteins, where phosphorylation occur, is used. In combination with mass spectrometry, this technique does not require the use of radioactive labeling or antibodies. The present work in spinach and Arabidopsis thaliana has identified and characterized several known phosphoproteins, new phosphorylation sites in well-known photosynthetic proteins, as well as two phosphoproteins previously unknown to be present in the photosynthetic membrane. Several photosystem II (PSII) core proteins become phosphorylated in their N-termini (D1, D2, CP43, PsbH), process involved in the regulation of the repair cycle of photo-damaged PSII complexes. The protein-protein interactions between PSII and its light harvesting complex (LHCII) seem to be affected by phosphorylation events in the interface area. In higher plants, phosphorylation sites have been identified in LHCII polypeptides, in one of the proteins (CP29) present in the interface area, as well as in the peripheral TSP9 protein. The TSP9 protein is unique among photosynthetic phosphoproteins, since it is a plant-specific soluble protein that becomes triple-phosphorylated in the middle part of the protein. It is also shown that photosystem I (PSI) is subjected to protein phosphorylation. The extrinsic PSI subunit PsaD becomes phosphorylated in its N-terminus. In addition, the latest characterized subunit of PSI, PsaP, is identified as a phosphoprotein. PsaP is an intrinsic protein assembled on the same side of the PSI complex as LHCII attaches. Several kinases are involved in phosphorylation of photosynthetic proteins, some more specific to PSII core proteins whereas others recognize LHCII proteins better. The STN8 kinase does not phosphorylate LHCII proteins, but is involved in the phosphorylation of the PSII core proteins D1, D2, CP43 and PsbH. STN8 is light-activated and is also specific in phosphorylation of threonine-4 (Thr-4) in the PsbH protein, but only after another kinase has phosphorylated Thr-2 first. A common feature of all kinases in plant photosynthetic membranes is the specificity for Thr residues and that the phosphorylation reactions occur in the N-terminal sequence of the proteins, except for the TSP9 protein. Nowadays, research is on the way to solve the complex network of regulation of photosynthetic activity via protein phosphorylation, but far more efforts are needed to get a complete view of the importance of all phosphorylation events and enzymatic specificity.

Woody plant encroachment is a globally-prevalent vegetation change phenomenon that has shifted grass-dominated ecosystems to mixed grass and woody plant matrices over the last century. In the Rio Grande Plains of Texas, the introduction of N-fixing woody legumes has increased above- and belowground primary productivity and changed the litter chemistry of the system, accelerating rates of belowground biogeochemical processes. The purpose of this study was to assess the impact of grassland to woodland transition on i) P concentrations in soil physical fractions that differ in their organic matter turnover rates, ii) P availability within the soil over the course of woody encroachment and across the landscape, and iii) microbial community composition and diversity. Soil samples were collected in remnant grasslands and four woody landscape elements (clusters, groves, drainage woodlands, and playas) along a 135-yr chronosequence of woody plant encroachment. P was fractionated by the Hedley method and P concentrations were determined by alkaline oxidation and lithium fusion coupled with ascorbic acid colorimetry. Bacterial and fungal communities were characterized by molecular methods. Whole soil P concentrations were 2-5X greater in woody landscape elements than in grasslands, and nutrient concentrations increased linearly with time following woody plant invasion in all but the slowest-cycling physical fractions. Plant-available P and organic P increased dramatically with time following encroachment. Changes in P availability were more pronounced in drainages and playas than in upland clusters and groves. Analysis of the bacterial and fungal communities demonstrated that microbial communities in grasslands differ at both phylum and genus level from the flora of the wooded landscape elements. This study demonstrates that woody encroachment strongly influences the distribution and availability of soil P and indicates that nutrient cycles in the soil are closely linked and similarly affected by increased woody plant abundance. Microbial communities under woody species differ in composition from those of the grasslands, and are likely contributing to the observed changes in nutrient availability. Since N and P are generally the most limiting nutrients in terrestrial ecosystems, increased stores of P are likely to alter rates of microbial processes, plant-microbe and plant-plant interactions, and successional dynamics in this ecosystem and similar landscapes around the world.

Rock grouting is performed to decrease the hydraulic conductivity around underground structures, such as tunnels and caverns. Cement grouts are often used and pumped into joint and fractures of the rock formation. Piston type pumps are mostly used for high pressure rock grouting. A pulsation effect is inevitable when using this type of pump due to the movement of the piston. The effect of this pulsation on rock grouting is yet to be known but believed to be benefi-cial for the penetration of the grout. Current flow meters used in the field are not accu-rate enough to determine the fluctuation of the flow rate when it is less than 1 l/min. In addition, currently available flow meters measure the average of the flow over a cer-tain period of time, hence the true fluctuation of the flow rate due to the pulsation of the piston remains unknown. In this paper, a new methodology, the so called ‘Ultrasound Velocity Profiling – Pressure Difference’ (UVP+PD) method has been introduced to show the pulsation effect when using a piston type pump. The feasibility of this method was successfully investigated for the direct in-line determination of the rheological properties of micro cement based grouts under field conditions (Rahman &amp; Håkansson, 2011). Subse-quently, it was also found that this method can be very efficient to measure the fluctu-ation of the flow rate for different types of pumps. From a grouting point of view the UVP+PD method can be used to synchronize the pressure and flow of a piston type pump by measuring the pulsation effect. Conse-quently it can be used as a tool for the efficiency and quality control of different types of pumps. / <p>QC 20121221</p>

A year-long study was conducted in Pinal County, Arizona to characterize fine and coarse particulate matter as a means of furthering our understanding of ambient concentrations and composition in rural, arid environments. Detailed measurement of ambient fine and coarse mass, ion, metal, and carbon concentrations at one-in-six day resolution was conducted at three sites from February 2009 to February 2010. Detailed organic carbon speciation was collected at 5-week resolution. A series of samples representing native soil, agricultural soil, road dust, and cattle feed lot material was collected, resuspended in the laboratory, and analyzed to provide a chemical source profile for each soil type yielding insights into unique source signatures. Observations within the chemical speciation data and subsequent modeling analysis show a strong impact from local sources at the Cowtown site where mass concentrations are highest. Source apportionment results confirm the significant impact from the cattle feedlot adjacent to the site. Chemical analysis of ambient particles and local feedlot material shows the presence of chemical marker species including phosphate which is unique to this source. Fugitive dust is a significant contributor to ambient particulate matter concentrations at all monitoring locations. Seasonal observations show higher concentrations during tilling and harvesting indicating the large role agricultural sources play on particle concentrations in this area. Chemical characterization and modeling show that re-entrained road dust is a significant factor. Fine particle modeling results indicate that concentrations are influenced significantly by motor vehicles including impacts from direct emissions including brake wear and indirect emissions including resuspended road dust. A significant fraction is also associated with crustal sources while about 5 g/m3 appears to be transported into the region from beyond the air shed. Detailed analysis of the local monsoon season indicates that monsoon rains serve to clean the atmosphere resulting in a marked decrease in ambient coarse mass and resulted in a period where local coarse PM concentrations measured at all sites became more uniform. The monsoon season also featured localized high wind events which severely increased coarse PM concentrations and often caused exceedences of the PM National Ambient Air Quality Standard.

A year-long study was conducted in Pinal County, Arizona to characterize fine and coarse particulate matter as a means of furthering our understanding of ambient concentrations and composition in rural, arid environments. Detailed measurement of ambient fine and coarse mass, ion, metal, and carbon concentrations at one-in-six day resolution was conducted at three sites from February 2009 to February 2010. Detailed organic carbon speciation was collected at 5-week resolution. A series of samples representing native soil, agricultural soil, road dust, and cattle feed lot material was collected, resuspended in the laboratory, and analyzed to provide a chemical source profile for each soil type yielding insights into unique source signatures. Observations within the chemical speciation data and subsequent modeling analysis show a strong impact from local sources at the Cowtown site where mass concentrations are highest. Source apportionment results confirm the significant impact from the cattle feedlot adjacent to the site. Chemical analysis of ambient particles and local feedlot material shows the presence of chemical marker species including phosphate which is unique to this source. Fugitive dust is a significant contributor to ambient particulate matter concentrations at all monitoring locations. Seasonal observations show higher concentrations during tilling and harvesting indicating the large role agricultural sources play on particle concentrations in this area. Chemical characterization and modeling show that re-entrained road dust is a significant factor. Fine particle modeling results indicate that concentrations are influenced significantly by motor vehicles including impacts from direct emissions including brake wear and indirect emissions including resuspended road dust. A significant fraction is also associated with crustal sources while about 5 g/m3 appears to be transported into the region from beyond the air shed. Detailed analysis of the local monsoon season indicates that monsoon rains serve to clean the atmosphere resulting in a marked decrease in ambient coarse mass and resulted in a period where local coarse PM concentrations measured at all sites became more uniform. The monsoon season also featured localized high wind events which severely increased coarse PM concentrations and often caused exceedences of the PM National Ambient Air Quality Standard.

No description available.

The primary objective of this research was to investigate the feasibility of calibrating ultrasound scanners to measure surface impedance from reflection data. The method proposed uses calibration curves from known impedance interfaces. This plot, or calibration curve, may then be used, with interpolation, to relate measured grey level to impedance for the characterization of tissue specimens with unknown properties. This approach can be used independent of different medical ultrasound scanner systems to solve for reproducible tissue impedance values without offline data processing and complicated custom electronics. <p>Two medical ultrasound machines from different manufacturers were used in the experiment; a 30 MHz and a 7.5 MHz machine. The calibration curves for each machine were produced by imaging the interfaces of a vegetable oil floating over varying salt solutions. <p>To test the method, porcine liver, kidney, and spleen acoustical impedances were determined by relating measured grey levels to reflection coefficients using calibration curves and then inverting the reflection coefficients to obtain impedance values. The 30 MHz ultrasound machines calculated tissue impedances for liver, kidney, and spleen were 1.476 ± 0.020, 1.486 ± 0.020, 1.471 ± 0.020 MRayles respectively. The 7.5 MHz machines tissue impedances were 1.467 ± 0.088, 1.507 ± 0.088, and 1.457 ± 0.088 MRayles respectively for liver, kidney and spleen. The differences between the two machines are 0.61%, 1.41%, and 0.95% for the impedance of liver, kidney, and spleen tissue, respectively. If the grey level is solely used to characterize the tissue, then the differences are 45.9%, 40.3%, and 39.1% for liver, kidney, and spleen between the two machines. The results support the hypothesis that tissue impedance can be determined using calibration curves and be consistent between multiple machines.

This research presents a system for mechanically characterizing single cells using automated micropipette aspiration. Using vision-based control and position control, the system controls a micromanipulator, a motorized translation stage, and a custom-built pressure system to position a micropipette (4 $\mu$m opening) to approach a cell, form a seal, and aspirate the cell into the micropipette for quantifying the cell's elastic and viscoelastic parameters as well as viscosity. Image processing algorithms were developed to provide controllers with real-time visual feedback and to accurately measure cell deformation behavior on the fly. Experiments on both solid-like and liquid-like cells demonstrated that the system is capable of efficiently performing single-cell micropipette aspiration and has low operator skill requirements. Once the system was validated, it was used to study voided urine cells. In this study, the mechanical properties of bladder carcinoma cells were investigated.

This research presents a system for mechanically characterizing single cells using automated micropipette aspiration. Using vision-based control and position control, the system controls a micromanipulator, a motorized translation stage, and a custom-built pressure system to position a micropipette (4 $\mu$m opening) to approach a cell, form a seal, and aspirate the cell into the micropipette for quantifying the cell's elastic and viscoelastic parameters as well as viscosity. Image processing algorithms were developed to provide controllers with real-time visual feedback and to accurately measure cell deformation behavior on the fly. Experiments on both solid-like and liquid-like cells demonstrated that the system is capable of efficiently performing single-cell micropipette aspiration and has low operator skill requirements. Once the system was validated, it was used to study voided urine cells. In this study, the mechanical properties of bladder carcinoma cells were investigated.