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norskBlar i tittel Fakultet for naturvitenskap og teknologi
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Overgangen fra eklogitt til amfibolitt. Et detaljstudium
(Master thesis; Mastergradsoppgave, 2007-05)Formålet med oppgaven er å gjøre en systematisk petrografisk og petrologisk undersøkelse av en mafisk linse med omgivende granat-glimmerskifer/marmor innen Tromsødekket. Den mafiske linsa har opprinnelig sannsynlig vært en basaltisk gang/sill som har blitt metamorfosert under eklogittfacies. Lokaliteten er blottlagt i ei veiskjæring ved universitetet i Tromsø (UiT). Den valgte mafiske linsa har en ... -
Overlevelsesanalyse med tidsavhengige forklaringsvariabler med bruk av Cox proporsjonal hasard regresjonsmodell
(Master thesis; Mastergradsoppgave, 2015-12-15)I denne mastergradsoppgaven ble det brukt overlevelsesanalyse med tidsavhengige variabler til å estimere en Cox proporsjonal hasard regresjonsmodell. Variablene stammet fra forskningsprosjektet ''Kvinner og kreft'' (The Norwegian Women and Cancer post genome cohort study - NOWAC) ved universitetet i Tromsø og besto av 57 561 kvinner. Modellen ble brukes til lage en modell av hasard raten til kvinnene ... -
Overview of the MOSAiC expedition: Physical oceanography
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-02-07)Arctic Ocean properties and processes are highly relevant to the regional and global coupled climate system, yet still scarcely observed, especially in winter. Team OCEAN conducted a full year of physical oceanography observations as part of the Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC), a drift with the Arctic sea ice from October 2019 to September 2020. ... -
Overview: Recent advances in the understanding of the northern Eurasian environments and of the urban air quality in China-a Pan-Eurasian Experiment (PEEX) programme perspective
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-04-06)The Pan-Eurasian Experiment (PEEX) Science Plan, released in 2015, addressed a need for a holistic system understanding and outlined the most urgent research needs for the rapidly changing Arctic-boreal region. Air quality in China, together with the long-range transport of atmospheric pollutants, was also indicated as one of the most crucial topics of the research agenda. These two geographical ... -
OXA-48-Mediated Ceftazidime-Avibactam Resistance Is Associated with Evolutionary Trade-Offs
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-27)Infections due to carbapenemase-producing Gram-negative pathogens are associated with limited treatment options and consequently lead to increased mortality and morbidity. In response, combinations of existing β-lactams and novel β-lactamase inhibitors, such as ceftazidime-avibactam (CAZ-AVI), have been developed as alternative treatment options. To understand the development of resistance and ... -
The OXA-class of β-lactamases. A structural view on antibiotic resistance
(Doctoral thesis; Doktorgradsavhandling, 2017-09-01)Antibiotic resistance is a topic that concerns everyone, and by 2050 deaths due to antibiotic resistant bacteria may surpass number of deaths due to cancer. The OXA-class of antibiotic resistance enzymes is a formidable threat, but has not received the same attention as other resistance enzymes. The goal of the project was to understand antibiotic resistance enzymes at an atomic scale and to develop ... -
Oxidative stress in two tropical species after exposure to diesel oil
(Peer reviewed; Journal article; Tidsskriftsartikkel, 2016-08-03)Recent offshore petroleum exploration has increased the risks of oil spills worldwide. We investigated biomarker responses to diesel oil exposure in two tropical and subtropical species, the clam Anomalocardia flexuosa and the polychaete Laeonereis culveri. Animals were exposed to oil-spiked sediment at two different concentrations (0.5 L and 1.0 L m−2). Activities of antioxidant enzymes catalase ... -
Oxygenated conditions in the aftermath of the Lomagundi-Jatuli Event: The carbon isotope and rare earth element signatures of the Paleoproterozoic Zaonega Formation, Russia
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-09)The c. 2.0 Ga Zaonega Formation of the Onega Basin (NW Russia) has been central in efforts to understand what led to the initial rise (Great Oxidation Event, GOE) and postulated fall in free atmospheric oxygen and associated high-amplitude carbon cycle excursions, the Lomagundi-Jatuli Event (LJE) and subsequent Shunga Event during Paleoproterozoic time. The Formation accumulated shortly after the ... -
p-SARS: Peer-to-peer search for a recommender system
(Master thesis; Mastergradsoppgave, 2003-12-15)WAIF started out in 2002 and the overall goal is to make the computers automatically search for relevant information based on the user’s preferences, and to push this information directly to the user wherever he/she is and to whatever device he/she has available. In other words, make the machines serve us, with as little human interaction as possible. This thesis focuses on a specific part of this ... -
Pairwise scale space comparison of time series with application to climate research
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012)In this paper, we study how sea surface temperature variations in the North Atlantic and the Norwegian Sea are correlated with the climate in the Northern Hemisphere in late Holocene. The analysis is performed by testing statistical hypotheses through novel scale space methodologies. In late Holocene, the proposed techniques reveal that the climate development in the subpolar North Atlantic has been ... -
Palaeoceanographic and climate changes during the Holocene in Hinlopen Strait, northern Svalbard
(Mastergradsoppgave; Master thesis, 2023-05-20)This study investigates the paleoceanographic changes in the Hinlopen Strait, situated between Spitsbergen and Nordaustlandet, through a multi-proxy analysis of sediment core HH15-1280-GC (439 m water depth). Located near the Polar Front, this region is highly sensitive to even minor alterations in the ocean circulation and climate, which can be reconstructed from marine sediment records. The core ... -
Palaeoceanographic and environmental changes in the eastern Fram Strait during the last 14,000 years based on benthic and planktonic foraminifera
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-14)Benthic and planktonic foraminifera, stable isotopes and other geochemical and sedimentological parameters have been investigated in a sediment core from Vestnesa Ridge (79°N, NW Svalbard margin, 1300 m water depth) in order to reconstruct the palaeoceanographic and palaeoenvironmental evolution of the eastern Fram Strait during the last 14,000 years. Our multiproxy data and, in particular, our ... -
Palaeoceanographic development in Leirdjupet Trough, western Barents Sea, during the Holocene: evidence from foraminiferal, isotopic and sedimentological records
(Master thesis; Mastergradsoppgave, 2015-12-14)The gravity core HH14-012GC from Leirdjupet Trough has been investigated to detect changes in sedimentation and the variations in distribution patterns of marine microorganisms (Planktic and Benthic Foraminifera) and stable isotope values of their shells to reconstruct the variability of the inflow of Atlantic water to the study area. The results are compared to published paleodata records to ... -
Palaeoceanographic reconstruction of surface-ocean changes in the southern Norwegian Sea for the last ~130,000 years based on diatoms and with comparison to foraminiferal records
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-28)Fossil marine diatom assemblages in a sediment core from the central northern Faroe slope in the Norwegian Sea were used to reconstruct palaeoceanographic changes in the surface water mixed layer from the last ~130,000 years (Marine Isotope Stage (MIS) 6/5 transition to MIS 1 (including the Eemian and Holocene interglacials) and to compare the results with previously published results on planktic ... -
Palaeoceanography of the Barents Sea continental margin, north of Nordaustlandet, Svalbard, during the last 74 ka
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-17)We investigated gravity core HH11‐09GC from 488 m water depth at the northern Svalbard margin in order to reconstruct changes in Atlantic Water (AW) inflow to the Arctic Ocean. The study was based on the distribution patterns of benthic and planktic foraminifera, benthic and planktic oxygen and carbon isotopes, lithology and physical properties of the sediments. The core contains sediments from ... -
Palaeoenvironment of the Barents Sea during the last deglaciation and Holocene : processes and timing
(Doctoral thesis; Doktorgradsavhandling, 2012-03-01)The scope of this PhD thesis is twofold: Firstly, processes, patterns and timing of the last deglaciation in the Barents Sea are reconstructed and secondly, depositional conditions on the Barents shelf during Holocene are elucidated. This cumulative PhD thesis encompasses an introductory part and five papers - three as first-author and two as co-author. Three papers are focused on the most prominent ... -
Palaeoproterozoic foreland fold-thrust belt structures and lateral faults in the West Troms Basement Complex, northern Norway, and their relation to inverted metasedimentary sequences
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-15)Palaeoproterozoic fold-thrust belt structures and steep, lateral shear zones characterize the foreland deformation of Neoarchaean basement tonalites in Vanna, West Troms Basement Complex, northern Norway. Low-grade par-autochthonous and allochthonous cover units (2.4–2.2. Ga) with sandstones and calcareous metapelites exist in separate areas of the foreland. They were formed as intracontinental rift- ... -
The Palaeoproterozoic Gallujavri Ultramafic Intrusion, Karasjok Greenstone Belt; Petrogenesis of a Trans-Crustal Magma System
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-02-14)The modern concepts of magmatic plumbing systems have evolved from simple models of melt-dominated crustal magma chambers to magmatic systems that span the continental crust. The geochemistry of these systems is challenging to model numerically because of a complex polybaric and multiphase evolution, which is not well described by mathematic end-member formulas. We propose that a recent modelling ... -
Palaeoproterozoic oxygenated oceans following the Lomagundi–Jatuli Event
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-16)The approximately 2,220–2,060 million years old Lomagundi–Jatuli Event was the longest positive carbon isotope excursion in Earth history and is traditionally interpreted to reflect an increased organic carbon burial and a transient rise in atmospheric O<sub>2</sub>. However, it is widely held that O<sub>2</sub> levels collapsed for more than a billion years after this. Here we show that black shales ... -
Paleo-klimatisk og oseanografisk utvikling i Ingøydjupet, gjennom deglasiasjon og Holosen, basert på undersøkelser av kornfordeling og bentiske foraminiferer
(Master thesis; Mastergradsoppgave, 2013-11-21)To kjerner fra Ingøydjupet i sørvest Barentshavet, 11HH-152MC og JM06-012GC, er blitt undersøkt for å undersøke den paleo-klimatiske og paleo oseanografiske utviklingen i Barentshavet. Dette er rekonstruert basert på undersøkelser av bentiske foraminiferer og kornfordeling. Kjernenes lengde er på henholdsvis ca 50 cm og 200 cm og 3 radiokarbon dateringer ligger til grunn for alderskronologien. ...
