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Field Scale Reservoir Simulation of CO2 Foam Mobility Control
Get PDFCarbon capture, utilization, and storage (CCUS) is crucial in achieving energy transition goals (IEA, 2023). CCUS involves the capture of CO2 from anthropogenic sources and utilizing it directly for EOR and subsequent storage or for other indirect applications (IEA, 2023). A major component of the CCUS value chain is utilizing CO2 in enhanced oil recovery (EOR) processes. However, CO2 EOR can suffer from gravity override, viscous fingering, and early gas breakthroughs caused by density and viscosity differences between CO2 and reservoir oil (Kovscek & Radke, 1993). Combining CO2 EOR with CO2 storage processes can provide an economically friendly way to produce energy while permanently storing CO2 in the subsurface which contributes to achieving the climate goals (Halland et al., 2018). This thesis is part of an international research program, led by the University of Bergen, which aims to optimize and field test CO2 foam systems for CO2 mobility control in EOR and CO2 storage. The objective of this work was to investigate field-scale CO2 foam for mobility control in a single injector radial model and in a high-resolution cross-section model. Using the radial model, foam generation and stability, injectivity, and propagation were investigated. The cross-section model was used to investigate the influence of different experimentally derived foam model parameters and injection strategies on CO2 mobility, sweep efficiency, and resulting oil recovery. In addition, the influence of pre-SAG injection on injectivity and post-SAG injection on oil production was investigated. The radial simulation model indicated foam generation in all cases with surfactant present and CO2 mobility was reduced. It was found that surfactant concentration affects foam strength but does not show much impact on foam propagation. However, foam concentration within the near well-bore area was significantly lower with low surfactant concentration. The foam was more stable at high oil foam tolerance than at low oil foam tolerance while larger surfactant and CO2 slug sizes increased CO2 injectivity than smaller slugs. In addition, the pre-injection of CO2 before SAG injection resulted in a stronger foam compared to pre-injecting water. However, pre-injection of water before SAG injection increased CO2 injectivity due to the lower BHP compared to pre-injection of CO2 before SAG. The cross-section model results indicated that CO2 foam can divert CO2 from the highest permeability layer to adjacent layers, thereby increasing sweep and producing more oil. A strong dependence of increased sweep and oil production to strong foam generation was observed. CO2 foam flooding delayed the gas breakthrough time and reduced the produced GOR significantly. This result contributed to the understanding of the foam flow process at the field scale. It provided a better understanding of the observed field pilot data that can be used for foam injection strategy optimization when a new pilot is to be designed for improved oil recovery.Master's Thesis in Petroleum TechnologyPTEK399MAMN-PET
In vitro study of the effect of cabozantinib (XL184) on canine oral melanoma cell lines
Get PDFMasteroppgave i biomedisinBMED395MAMD-MEDB
‘Musical-Markers’: The effects of music on brain reserve, white matter microstructure, and structural network topology in subjects along the Alzheimer’s Disease continuum
Get PDFDenne avhandlingen utforsker potensialet for musikkterapi som en ikke-farmakologisk behandling for Alzheimers sykdom (AD), en ledende årsak til demens. Bevaringen av musikalsk hukommelse til tross for den omfattende kognitive nedgangen som sees ved AD, har vekket interesse for musikkens terapeutiske rolle. Denne avhandlingen hevder at musikk ikke bare forbedrer kognisjon og emosjonell velvære, men også fremmer nevroplastisitet, noe som potensielt kan påvirke hjernens strukturelle integritet, som er mindre forstått. Organisert i fire sammenhengende artikler, fokuserer denne avhandlingen unikt på forskjellige dimensjoner av musikkterapiens innflytelse på hjerneplastisitet og kognitiv helse ved AD.
Artikkel I: Denne artikkelen undersøker potensialet for musikkterapi ved AD, samtidig som den gir en gjennomgang av det vitenskapelige grunnlaget for musikk og hukommelse, musikkfremkalte autobiografiske minner (MEAMs) og musikkfremkalte følelser. Den gir en oversikt over litteraturen som undersøker de terapeutiske effektene av musikkterapi, samt de potensielle hjernemekanismene som ligger til grunn for de observerte effektene. Artikkelen diskuterer de bredere implikasjonene av musikkterapi i fremme av kognitiv helse og foreslår at musikkbaserte intervensjoner kan fungere som en verdifull tilleggsterapi for personer med AD. Dette arbeidet bidrar til den økende mengden av bevis som støtter musikkens nevrobeskyttende effekter og understreker behovet for videre forskning for fullt ut å forstå mekanismene hvorved musikkterapi kan modulere nevrodegenerative prosesser.
Artikkel II: Denne artikkelen introduserer studien Alzheimer’s and Music Therapy (ALMUTH), en parallell tre-armet randomisert kontrollert studie (RCT) utført i Bergen, Norge, med 18 pasienter med mild til moderat AD. Denne åpen etikett-studien inkluderte to aktive NPT-er: musikkterapi (MuTh) og fysisk aktivitet (PA), sammenlignet med en passiv kontrollgruppe (ingen intervensjon). Deltakerne deltok på opptil 40 ukentlige økter over 12 måneder, med nevropsykologisk testing og MR-skanninger (strukturell, funksjonell og diffusjonsvektet avbildning) utført ved baseline og oppfølging. I denne artikkelen gjennomførte vi en gjennomførbarhetsvurdering av ALMUTH-protokollen hos 18 pasienter med mild til moderat AD for å vurdere om fortsatt rekruttering av AD-pasienter var berettiget. 9 Gjennomførbarhetsresultatene ble vurdert som gjennomførbare hvis de oppfylte målte kriterier. Disse inkluderte rekrutteringsrater og målrater, rekrutteringskostnader, retensjonsrater, frafallsrater, overholdelse av protokoll, differensielle frafallsrater, tilstrekkelig utstyr og fasiliteter, datakompletthet, aksept av intervensjoner, og studiefidelitet. Nøkkelfunn fra studien indikerte at deltakerne hadde problemer med å følge protokollen. På grunn av den raske progresjonen av Alzheimers sykdoms symptomer, trakk halvparten av de inkluderte pasientene seg fra studien, noe som resulterte i en frafallsrate på 50 % (9 av 18) og en retensjonsrate på 50 % (9 av 18). Blant de som fullførte post-evalueringen 12 måneder senere, var overholdelsen av protokollen også 50 %, med ansatte som identifiserte en rekke problemer som krevde ytterligere betydelige modifikasjoner av hovedstudieprotokollen. Disse resultatene førte til at ALMUTH-studien utvidet rekrutteringskriteriene til å inkludere tidligere, pre-AD-stadier, inkludert individer med mild kognitiv svikt (MCI), subjektiv kognitiv svikt (SCD), og hukommelsesklager.
Artikkel III: Forskning har vist at musikalsk engasjement kan ha en betydelig strukturell innvirkning på hjernen, hovedsakelig på grunn av dets nevroplastiske effekter. Disse nevroplastiske endringene antas å bidra til å bremse hjernealdring, som vist i en studie som fant betydelig lavere hjernealdringsskår hos både amatører og profesjonelle musikere sammenlignet med ikke-musikere. I artikkel III undersøkte vi om musikerstatus og musikalske aktiviteter, inkludert musikalsk trening (MT) og aktivt musikalsk engasjement (AME), påvirker hjernealdring i en kohort på 125 friske individer. Ved hjelp av Brain Age Gap Estimation (BrainAGE)-algoritmen analyserte vi om disse musikalske faktorene hadde en aldersbremmende effekt. Våre funn indikerer at musikerstatus ikke påvirket BrainAGE-skår, mens fysisk aktivitet gjorde det. Selv om MT- og AME-delskalaene til Gold-MSI ikke forutsier BrainAGE-skår, er disposisjonell resiliens, spesifikt evnen til å håndtere utfordringer, knyttet til både MT og AME, samt musikalsk nytelse. Selv om vår studie ikke replikerte resultatene fra en tidligere studie om hjernealdring, fant vi at musikalsk trening og aktivt musikalsk engasjement er assosiert med resiliensfaktoren utfordring. I tillegg var BrainAGE knyttet til visse livsstilsfaktorer, inkludert bruk av allergimedisin og fysisk aktivitet. Deltakere som regelmessig 10 brukte allergimedisin og var fysisk aktive hadde lavere BrainAGE-skår sammenlignet med de som ikke brukte allergimedisin eller deltok i fysisk aktivitet. Artikkel IV: Gitt bevisene for at musikalske aktiviteter kan bevare hjerneplastisitet og indusere strukturelle endringer i hjernen, undersøker denne artikkelen deres innvirkning på hjerneforbindelser i områder relatert til hukommelse hos en kohort av individer langs ADkontinuumet.
Artikkel IV undersøkte effekten av musikkoppfatningsferdigheter, aktivt musikalsk engasjement, og musikalsk trening på strukturell konnektivitet i hjerneområder relatert til hukommelse, følelser og læring hos individer med varierende grader av hukommelsesvikt. Ved bruk av diffusjonstensoravbildning (DTI) og grafteoretisk analyse, vurderte vi 78 deltakere i alderen 42 til 85 år, og analyserte hvordan musikalske aktiviteter påvirker hjerneforbindelser, samtidig som vi kontrollerte for stadier av hukommelsesvikt (SOMI). Vi observerte at forbedret strukturell konnektivitet i høyre hippocampus og høyre posterior cingulate cortex var korrelert med forbedrede lokale nettverksmålinger, slik som klyngekoeffisient og mellomledd sentralitet, spesielt hos individer med høyere musikkoppfatningsferdigheter, inkludert melodi- og rytmeoppfatning. Musikalsk trening forbedret spesielt klyngekoeffisienten i høyre hippocampus og nodal grad i høyre midtcingulate gyrus, mens aktivt musikalsk engasjement økte egenvektor sentraliteten til høyre hippocampus. I tillegg var musikalsk trening knyttet til forbedrede globale nettverksmålinger, slik som global effektivitet og karakteristisk stibredde. Disse funnene, avledet fra diffusjon MRI og grafteoretisk analyse, understreker den betydelige innvirkningen av musikalske aktiviteter på strukturell konnektivitet i nøkkelområder i hjernen relatert til hukommelse, følelser og læringThis thesis explores the potential of music therapy as a non-pharmacological treatment for Alzheimer’s Disease (AD), a leading cause of dementia. The preservation of musical memory despite the extensive cognitive decline seen in AD has spurred interest in music's therapeutic role. This thesis posits that music not only enhances cognition and emotional well-being but also promotes neuroplasticity, potentially modulating the brain's structural integrity, which is less understood. Organized into four interconnected articles, this thesis uniquely focuses on different dimensions of music therapy's influence on brain plasticity and cognitive health in AD.
Paper I: Article I investigates the promise of music therapy for AD, while reviewing the scientific basis for music and memory, music-evoked autobiographical memories (MEAMs) and music-evoked emotions, an overview of the literature investigating the therapeutic effects of MuTh, and the potential brain mechanisms underlying the observed effects. The article discusses the broader implications of music therapy in promoting cognitive health, proposing that music-based interventions could serve as a valuable adjunctive treatment for those with AD. This work contributes to the growing body of evidence supporting the neuroprotective effects of music and highlights the need for further research to fully elucidate the mechanisms by which music therapy can modulate neurodegenerative processes.
Paper II: We introduce the Alzheimer’s and Music Therapy (ALMUTH) study, a parallel three-arm randomized controlled trial (RCT) conducted in Bergen, Norway, involving 18 mild-to-moderate AD patients. This open-label trial featured two active non-pharmacological therapies (NPTs): Music Therapy (MuTh) and Physical Activity (PA), compared to a passive control (no intervention). Participants attended up to 40 weekly sessions over 12 months, with neuropsychological testing and MRI scans (structural, functional, and diffusion-weighted imaging) conducted at baseline and follow-up. In Article II, we performed a feasibility assessment of the ALMUTH protocol in 18 mild-to-moderate AD patients to assess the ALMUTH protocol including if the continued recruitment of AD patients was warranted. Feasibility outcomes were assessed and were determined as feasible if they met the target criteria. The feasibility outcomes included 6 recruitment rates and target rates, recruitment costs, retention rates, attrition rates, adherence to protocol, differential attrition rates, sufficient facilities and equipment, data completeness, and acceptability of interventions, and study fidelity. Key feasibility findings from the study indicated that participants struggled to adhere to the protocol. Due to the rapid acceleration of Alzheimer's disease symptoms and progression, half of the enrolled patients withdrew from the study, resulting in an attrition rate of 50% (9 out of 18) and a retention rate of 50% (9 out of 18). Among those who completed the post-assessment 12 months later, adherence to the protocol was also 50%, with staff identifying numerous issues that required further significant modifications to the main study protocol. These outcomes led the ALMUTH study to broaden its recruitment criteria to include earlier, pre-AD stages, including individuals with mild cognitive impairment (MCI), subjective cognitive decline (SCD), and memory complaints.
Paper III: Research has shown that musical engagement can have a significant structural impact on the brain, largely due to its neuroplastic effects. These neuroplastic changes are believed to contribute to the deceleration of brain aging, as evidenced by one study that found significantly lower brain aging scores in both amateur and professional musicians compared to non-musicians. In Article III, we investigated whether musician status and musical behaviors, including musical training (MT) and active musical engagement (AME), influence brain aging in a cohort of 125 healthy individuals. Using the Brain Age Gap Estimation (BrainAGE) algorithm, we analyzed whether these musical factors produced an age-decelerating effect. Our findings indicate that musician status did not influence BrainAGE scores, whereas current physical activity did. Although the MT and AME subscales of the Gold-MSI do not predict BrainAGE scores, dispositional resilience, specifically the ability to deal with challenges, is linked to both MT and AME, and musical pleasure. While our study did not replicate results from a previous brain aging study, we found that musical training and active musical engagement are associated with the resilience factor of challenge. Additionally, BrainAGE was linked to certain lifestyle factors, including the use of allergy medication and engagement in physical activity. Participants who regularly used allergy medication and were physically active had lower BrainAGE scores compared to those who did not use allergy medication or engage in physical activity. 7
Paper IV: Given evidence that musical activities can preserve brain plasticity and induce brain structural changes, this paper examines their impact on brain connectivity in memory-related areas in a cohort of individuals along the AD continuum. Article IV examined the impact of music perception skills, active musical engagement, and musical training on structural connectivity in brain areas related to memory, emotion, and learning in individuals with varying degrees of memory impairment. Using diffusion tensor imaging (DTI) and graph theoretical analysis, we assessed 78 participants aged 42 to 85, analyzing how musical activities influence brain connectivity, while controlling for stages of memory impairment (SOMI). We observed that enhanced structural connectivity in the right hippocampus and right posterior cingulate cortex was correlated with improved local network metrics, such as clustering coefficient and betweenness centrality, particularly in individuals with higher music perception skills, including melody and beat perception. Musical training specifically enhanced the clustering coefficient in the right hippocampus and the node degree in the right mid cingulate gyrus, while active musical engagement increased the eigenvector centrality of the right hippocampus. Additionally, musical training was linked to improved global network metrics, such as global efficiency and characteristic path length. These findings, derived from diffusion MRI and graph theoretical analysis, underscore the significant impact of musical activities on structural connectivity in key brain regions related to memory, emotion, and learning.Doktorgradsavhandlin
Population effects of fear-inducing signals in digital songbirds
Get PDFAnthropogenic environments are rapidly changing. Reactions to these changes within prey
populations can become detrimental since behavioral strategies for foraging and vigilance are
adapted to the ancestral environment. Ecology of Fear studies show that fear alone can halve
songbird populations in five years, not considering lasting transgenerational impacts.
Ecologists point towards the need for explanations for this phenomenon, but theoretical
models have yet to tackle the challenge of predicting how rapid environmental changes affect
prey behavior and survival.
This thesis presents a new, object-oriented model that bridges ecology and subjective
cognition. It simulates how evolved emotions governed by two genes related to fear and
hunger shape the behavioral patterns of digital songbirds experiencing a sudden increase in
perceived risk. The thesis model consists of two phases: First, it evolves digital songbirds
equipped with genes for fear and hunger through a genetic algorithm. Then, it exposes these
evolved digital songbirds to greater levels of predator presence, exceeding that of their
ancestral environment. By disabling the predator attack, the model predicts how fear alone
changes evolved behavioral patterns in the simulated population.
The model results show that as fear levels increase, all simulated populations experience a
decrease in average body mass and, consequently, in expected fecundity. Additionally, the
simulated populations with unique evolved gene pools each exhibited distinct patterns of
body mass distribution as fear levels increased, indicating altered foraging strategies under
heightened fear conditions. However, due to its current simplicity, the model is not yet
suitable for real-world application.Masteroppgave i biologiBIO399MAMN-HAVSJMAMN-BI
Environmental exposures and fecundability: The Norwegian Mother, Father, and Child Cohort study
Get PDFPrevious studies have linked certain environmental exposures to reduced fecundability, influencing exposure recommendations. We continue to encounter numerous environmental exposures in our everyday lives, and further evidence is needed regarding their effects on fecundability. We evaluated associations between various self-reported environmental exposures and fecundability, measured as time to pregnancy, in 64,942 women and 53,219 men participating in the Norwegian Mother, Father, and Child Cohort study (MoBa). Women reported on 17, and men on 19, environmental exposures, including heavy metals, pesticides, paints, and radiation. Fecundability ratios (FR) were estimated using log-binomial regression, comparing likelihood of conception during a given menstrual cycle between exposed versus unexposed participants. About 50 % of women and 75 % of men reported minimum one environmental exposure. Exposure to any pesticide (FR 0.94 [95 % CI 0.91-0.98]), and frequent exposure to photographic chemicals (FR 0.84 [95 % CI: 0.73-0.96]), was associated with decreased fecundability in women. We also observed a tendency of a slightly higher fecundability among women and men exposed to disinfectants (FR 1.02 [95 % CI: 1.00-1.04] and 1.03 [95 % CI: 1.00-1.06], respectively). Our results suggests that exposure to pesticides and photographic chemicals could affect women's fecundability.publishedVersio
Recognizing international protection how institutional arrangements affect asylum decisions
Get PDFMore than 70 years after the adoption of the United Nations’ 1951 Refugee Convention, there still exists large cross-country differences in terms of protection recognition. In this article, we argue that cross-country differences are likely due to different opportunity structures: because international protection stems from the administrative-legal procedures through which claims are examined, we investigate the institutional arrangements that make up Refugee Status Determination systems. We collect original data covering 14 European countries, Canada and South Africa over the years 2000–2020 and test the relationship between institutional arrangements and recognition rates. We find that the actors involved in the decision-making process matter: a plurality of actors likely leads to fairer outcomes, depending on which procedure or stage these actors are involved. Importantly, we report that extensive procedural rights, and guarantee of their enjoyment on the part of asylum seekers, significantly correlate with asylum seekers’ chances to see their claim recognized.publishedVersio
«It is about being able to see yourself as a resource [ ] have confidence that people want to be with you» A qualitative study on social relations and social participation in higher education for students with physical disabilities.
No full textMasteroppgave i helsefremmende arbeid og helsepsykologiHEFR395MAPS-HEF
Ethical approaches for engaging extended peer communities: Insight into responsible workshopping with citizens
Get PDFThe United Nation’s Sustainable Development Goals (SDGs) represent the most ambitious and encompassing global framework for ecological, economic, and social sustainability for our planet to date. However, the relevance of the global goals to local actions remains elusive and opaque, which presents a real risk that society will be unable to adapt to growing environmental risks, such as climate change. Thus emerges the need for a responsible and ethical SDG localization process. We use a normative approach to engage a local extended peer community, which took the form of an interactive, day-long workshop. This paper describes how the T.R.U.S.T ethos of post-normal science is used to co-design and implement the workshop, which is then reviewed as a heuristic inquiry using the Three Spheres of Transformation framework for sustainability. The result of this workshop is a realization of the extended peer community that the interconnectedness of personal values, community values, and the SDGs can set a more coherent path for local collaboration across sectors. As such, this mode of using the T.R.U.S.T ethos of PNS and Three Spheres of Transformation frameworks in the SDG localization process represents an ethical approach in post-normal science.publishedVersio
Seasonal variation in migration routes of Common Whitethroat Curruca communis
Get PDFAlthough geolocator tracking of small passerines has become commonplace in the last two decades, this tool is still underutilized for gathering natural history data of migration in many species. Common Whitethroat (Curruca communis) is one of the most numerous Afro-Palearctic migrants. However, our knowledge of the species’ migration ecology remains limited. Here, we combine ring-recovery analyses with geolocator tracking to describe migration routes and population-specific non-breeding areas in this long-distance migrant. Linkages between breeding, passage and non-breeding areas based on ring-recovery records revealed a strong correlation in longitudes, indicating parallel migration system and population-specific non-breeding grounds in whitethroats. Migration route simulation using EURING data suggested a possible migratory divide in Central Europe in autumn, while broad front migration across the Mediterranean occurs in spring. Geolocator-tracked whitethroats from Czechia (Central Europe) and Latvia (North-eastern Europe) migrated to non-breeding sites in Central Africa, where they first resided in the Sahel region before moving farther to a second non-breeding site in November/December. Major stopovers were associated with crossing of ecological barriers. A single Latvian bird with a repeat track showed similar migration patterns in both years, possibly visiting the same non-breeding sites in consecutive years. Both ringing and tracking data revealed clockwise loop migration between breeding and non-breeding sites.publishedVersio
"Det er som å jobbe med voldsproblematikk uten å spørre ‘slo du eller sparket du?’" En kvalitativ studie om samarbeid ved behandling av barn og unge med skadelig seksuell atferd
Get PDFEn betydelig andel seksuelle overgrep mot barn blir begått av andre barn og unge. Likevel er barn og unge med skadelig seksuell atferd en understudert gruppe. For å forebygge seksuelle overgrep mot barn er det viktig at barn og unge med skadelig seksuell atferd får nødvendig hjelp. Formålet med studien har vært å fremheve betydningen av samarbeid ved behandling av skadelig seksuell atferd. Problemstillingen var: «Hvordan opplever spesialister/terapeuter samarbeid med barneverntjenesten og familier ved behandling av barn og unge med skadelig seksuell atferd?». Studien baserer seg på 11 kvalitative intervju, hvor inklusjonskriteriet var at deltakerne hadde kjennskap til og/eller erfaring med behandling av barn og unge med skadelig seksuell atferd. Funn fra studien viste at felles innsats fra hjelpeapparat og familie ofte var avgjørende for vellykket behandling. Det viste seg imidlertid at skadelig seksuell atferd hos barn og unge fremsto som et unevnelig tema, noe som utfordret samarbeidet. I møte med omsorgspersoner og hjelpeapparat ble dette illustrert som «sprengstoff i familien» og «berøringsangst i barneverntjenesten». Konsekvensene av dette syntes å være krise i familien og et utnyttet potensial i barneverntjenesten. Sentrale implikasjoner av studien tydeliggjorde at det er nødvendig å rette fokus mot tabu om skadelig seksuell atferd som syntes å ta stor plass i arbeidet med disse barna. For at barneverntjenesten skal bli bedre rustet til å håndtere disse sakene, innebærer det at kontaktpersoner tørr å gå inn i detaljer omkring barnets atferd, til tross for ubehaget.Masteroppgave i barnevernMABARN351MAPS-BAR