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On the validity of electric brain signal predictions based on population firing rates
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Effects of temperature and insect herbivores on seedling survival in alpine ecosystems
Get PDFSuccessful seedling recruitment is vital for long-term vegetation dynamics and persistence of alpine ecosystems, yet will also be important for successful upslope migration of boreal plants under climate warming. Seedling mortality is often attributed to insect herbivory, and the interaction is predicted to strengthen under climate warming. However, we know little about the drivers of alpine insect herbivory, particularly on seedlings. To evaluate how establishment of upslope migrating boreal species may be affected by increasing temperatures and insect herbivores, I transplanted boreal seedlings in a factorial design using an elevational gradient, experimental warming using open-top-chambers (OTCs), and insect exclosures. I also measured soil moisture to address the drying effect of higher temperatures on seedling survival. Higher temperatures increased seedling survival, but the effect was mediated by soil moisture. Seedlings were recorded to have high levels of insect herbivory, regardless of temperature treatment or elevation. My findings provide a rare documentation of the interactions between insects and seedlings in alpine ecosystems. By selectively grazing on seedlings insect herbivores may, in part, currently be dictating alpine plant community dynamics. The same mechanisms may mitigate or modify the upslope migration of boreal plants, where species specific seedling palatability and climatic tolerances may determine the relative strength of positive or negative effects of insect herbivores. Long-term impacts of climate warming on alpine plant communities will be influenced by the responses of insect herbivores and seedlings
Halomonas sp. MC140, a polyhydroxyalkanoate (PHA) producer isolated from the Arctic environment
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Fra vintermodus til sommermodus – når ender vårknipa til svalbardreinen?
Get PDFVårknipa er et begrep som brukes for å beskrive den tøffe perioden i overgangen fra vinter til vår. Det referer til den kritiske perioden hvor vinterens fettreserver nærmer seg oppbrukt samtidig som næringstilgangen enda er dårlig på grunn av manglende vegetasjonsvekst. Arter i Arktis har utviklet fysiologiske tilpasninger for å tåle den tøffe vinteren. Svalbardreinsdyr (Ranigfer tarandus platyrhynchus) regulerer blant annet energibruken ved å redusere aktivitetsnivået og senke hjertefrekvensen om vinteren, noe som reduserer energibehovet når næringstilgangen er lav. Tidligere studier har vist at svalbardreinen har en markant økning i aktivitetsnivået omtrent når våren setter inn, men hva som påvirker når dette knekkpunktet skjer er ukjent.
I denne masteroppgaven undersøker jeg aktivitetsmønstre hos to populasjoner av svalbardreinsdyr som holder til i Ny-Ålesund og i Reindalen. Jeg bruker GPS data fra 238 individ-år fra Ny-Ålesund og 390 individ-år fra Reindalen. Disse dataene ble brukt for å se på om det er en geografisk variasjon i når aktivitetsnivået øker, samt hvordan aktivitetsnivået påvirkes av årlig variasjon i miljøvariabler som snøforhold, meteorologisk start for vår (temperatur) og vekstsesongens start, og til slutt individuelle variabler som vekt, drektighet og alder.
Resultatene viser en geografisk variasjon i tidspunktet for knekkpunktet. I gjennomsnitt kommer knekkpunktet 2,5 dager senere i Ny-Ålesund enn i Reindalen. Analysene av miljøforhold ble gjort med data fra Reindalen, og viser at temperatur er den beste forklaringen for tidspunktet til knekkpunktene. Også modellen basert på tidspunktet for når landskapet er 10% snøfritt ga gode resultater, og var sterkt konkurrerende med temperaturmodellen. Når det gjelder individuelle faktorer, hadde både drektighetsstatus og vekt signifikant effekt. Knekkpunktet inntreffer i gjennomsnitt 2,8 dager senere hos drektige simler. Hvis vekta til en simle øker med 5kg, vil knekkpunktet komme én dag senere. Det er en tydelig sammenheng mellom vekt og drektighet på simla, da tyngre simler ofte er drektige.
Resultatene har praktisk betydning for forståelsen av svalbardreinens overlevelse og reproduksjon under krevende forhold. Dersom vårknipa inntreffer senere enn normalt, kan det få stor innvirkning på dyrenes helse og overlevelse. Studien viser at temperatur er en av de beste forklaringsvariablene for tidspunktet for knekkpunktet. Dette er særlig relevant fordi temperaturdata er lett tilgjengelig fra værstasjoner. Det gir forvaltningen en enkel og konkret indikator på hvor krevende våren har vært for bestanden, noe som kan være nyttig ved vurdering av jaktkvoter og andre forvaltningstiltak. Funnene understreker viktigheten av å forstå hvordan både miljømessige og individuelle faktorer påvirker reinsdyrenes fysiologiske tilpasninger til klimaendringer. Dette er, så vidt jeg vet, det første studiet som systematisk undersøker hvordan slike variabler påvirker knekkpunktet i aktivitetsmønstre hos svalbardrein. Det gir viktige innsikter for fremtidig forvaltning og bevaring av arten i et klima som er under stadig forandring.The hunger gap is a term used to describe the challenging transition period between winter and spring. It refers to the critical phase when the fat reserves from the winter are nearly depleted while food availability remains low due to delayed vegetation growth. Arctic species have evolved physiological adaptions to endure the harsh winter. Svalbard reindeer (Rangifer tarandus platyrhynchus) regulate their consumption by reducing activity levels and lowering heart rates during winter, thereby decreasing their energy requirements when food is scarce. Previous studies have shown that Svalbard reindeer experience a significant increase in activity around the onset of spring, but what determines the timing of this breakpoint remains unknown.
In this master’s thesis, I will investigate activity patterns in two populations of Svalbard reindeer located in Ny-Ålesund and Reindalen. I used GPS data from 238 individual-years from Ny-Ålesund and 390 individual-years in Reindalen. These data were used to examine whether there is geographic variation in the timing of increased activity, and how the timing is influenced by annual variation in environmental variables such as snow conditions, meteorological spring (based on temperature), and the growing season onset, as well as individual variables like body mass, pregnancy status, and age.
The results show a geographic variation in the timing of the breakpoint. On average, the breakpoint occurs 2.5 days later in Ny-Ålesund than in Reindalen. Analyses of environmental factors were conducted using data from Reindalen and show that temperature is the best predictor of breakpoint timing. The model based on the date when the landscape is 10% snow-free also performed well and was strongly competitive compared to the temperature model. Regarding individual factors, both pregnancy status and body mass had significant effects. On average, the breakpoint occurred 2.8 days later in pregnant females. A 5 kg increase in body mass delayed the breakpoint by one day. There is a clear relation between body mass and pregnancy, as heavier females are more often pregnant.
The findings have practical implications for understanding the survival and reproduction of Svalbard reindeer under challenging conditions. If the hunger gap occurs later than usual, it may greatly impact the animals’ health and survival. The study shows that temperature is one of the best predictors of breakpoint timing, which is particularly relevant because temperature data is readily available from weather stations. This provides wildlife managers with a simple and concrete indicator of how difficult spring conditions have been for the population, which may be useful when assessing hunting quotas and other management measures. The findings emphasize the importance of understanding how both environmental and individual factors influence the reindeer’s physiological adaptations to climate change. To my knowledge, this is the first study to systematically investigate how such variables affect the activity breakpoint seen in Svalbard reindeer. It provides important insights for future conservation and management of the species in a rapidly changing climate
Is there any scientific evidence supporting a causal association between pyometra in bitches and the development of immune complex mediated glomerulonephritis? : a literature review
Get PDFI henhold til veterinærmedisinsk patologisk litteratur, eksisterer det i dag en kausal sammenheng mellom pyometra og immunkompleksmediert glomerulonefritt. Likevel var det årsak til å mistenke at det manglet tilstrekkelig vitenskapelig belegg som underbygger denne sammenhengen, noe som blir undersøkt i denne litteraturstudien. Ved evaluering av tidligere studier gjort på området, ble det spesielt fokusert på artiklenes bruk av diagnostiske verktøy og deres tolkning av resultatene. Kun 4 av 8 inkluderte studier konkluderte med en kausal sammenheng mellom de to lidelsene pyometra og immunkompleksmediert glomerulonefritt (ICGN). Ingen av disse brukte imidlertid nødvendige diagnostiske modaliteter i henhold til dagens krav, og konklusjonene kan derfor ikke ansees som pålitelige. To av de resterende artiklene var de eneste som oppfylte kravene stilt innledningsvis for påvisning av ICGN. Det gjorde at man verken kunne konkludere med en sikker sammenheng, eller ikke. For å konkludere, trengs det mer forskning ved bruk av nødvendige diagnostiske metoder.VE
Second-Order Energy Chain Analysis of alternative fuels (WTW- analysis)
Get PDFEt skifte mot bærekraftig transport krever en avansert forståelse av de totale miljøpåvirkningene fra alternative drivstoff, utover bare utslipp fra eksosrøret. Denne masteroppgaven benytter en energikjedeanalyse av andre orden, med anvendelse av Well-to-Wheel (WTW)-rammeverket, for å sammenligne energiforbruk og klimagassutslipp. Den sammenligner syv alternative drivstoffkilder for privatbiler: fra råolje til diesel, kull og vind til elbiler, naturgass med/uten karbonfangst, EU-strømmiks, og vindbasert elektrolyse for å produsere hydrogen til brenselcellebiler.
Gjennom systematiske undersøkelser av hele kjeden fra ressursutvinning til drivstoffproduksjon, distribusjon og sluttbruk, gir analysen totale estimater for energiforbruk i hver kjede (MJ/km), kumulativ effektivitet, samt CO₂-ekvivalente utslipp (g CO₂-eq/km). Analysen baserer seg på forutsetninger om Beste Tilgjengelige Teknologi (BAT), og inkluderer sensitivitetsanalyser for viktige parametere som virkningsgrad ved kullkraftverk, effektivitet i dampreformering av metan, effektivitet for CCS, og effektiviteten i EU sin energimiks.
Resultatene viser at elbiler drevet med vindkraft gir høyest effektivitet og lavest utslipp, mens kullbaserte elbiler og hydrogen produsert fra naturgass uten CCS medfører betydelige utslipp. Vindbasert grønt hydrogen er best når det gjelder klimaeffekt blant alle hydrogenalternativer, selv om energibehovet for lagring og distribusjon representerer utfordringer. Studien understreker at avkarbonisering av energiforsyningen oppstrøms er avgjørende, og at politiske tiltak bør støtte integrering av fornybar energi i produksjon av strøm og hydrogen.
Denne forskningen bidrar til innsikt i kompromisser i energikjeder, som kan danne grunnlag for kunnskapsbaserte beslutninger innen bærekraftig transportplanlegging og klimapolitikk.A shift towards sustainable transport involves an advanced understanding of the entire environmental implications of alternative fuels beyond tailpipe emissions. This thesis uses a second-order energy chain analysis with the application of a Well-to-Wheel (WTW) framework to benchmark the energy consumption as well as the greenhouse gas emissions. It compares seven alternative fuel sources for private cars: from crude oil to diesel, coal, and wind to electric vehicles, natural gas with/without carbon capture, EU electricity mix, and wind-based electrolysis to produce hydrogen to drive fuel cell electric vehicles.
Through systematic examinations of complete upstream and downstream processes from resource extraction to fuel production, distribution, to end-use, the analysis offers overall estimates of the energy consumption in each chain (MJ/km), cumulative efficiency, as well as CO₂-equivalent emissions (g CO₂-eq/km). The analysis uses the assumptions of Best Available Technology (BAT). It also performs a sensitivity analysis on important parameters such as plant efficiency in coal, steam methane reforming efficiency, CCS efficiency, and EU energy mix efficiency.
Results indicate that electric vehicles with wind power provide the highest efficiency with the least emissions, while coal-fueled EVs and natural gas-based hydrogen without CCS release significant emissions. Wind-based green hydrogen is the climate performance winner among all the hydrogen options, although storage and distribution energy needs pose issues. The research asserts that decarbonizing upstream energy supplies is critical, with supporting policy interventions in favor of integrating renewable energy to produce electricity and hydrogen.
This research assists in gaining insights into energy chain trade-offs, which will help make evidence-informed decisions regarding sustainable transport planning and climate policy
Metode for syntetiske profiler av strømpris og utslippsintensitet: En statistisk tilnærming basert på historiske data
No full textI denne masteroppgaven er det utviklet syntetiske profiler for strømpris og utslippsintensitet basert på historiske data fra perioden 2015–2024. Formålet har vært å etablere en enkel og transparent metode som kan benyttes i analyser av energisystemer og klimatiltak. Ved å bruke statistiske transformasjoner som normalisering og medianberegning er det laget representative profiler på års-, måneds- og døgnnivå. Resultatene viser at metodikken gir god samsvar med observerte data i normale år, og fanger opp viktige sesong- og døgnmønstre. Samtidig har modellen begrensninger i år med høy volatilitet eller raske strukturelle endringer. Profilene kan skaleres til ulike scenarioer og er egnet for å vurdere når ulike teknologier, som varmepumper og solceller, har størst potensial for kostnads- og utslippsreduksjon. Oppgaven viser at enkle statistiske metoder kan gi nyttige innsikter uten behov for avansert modellering.This master’s thesis develops synthetic profiles for electricity prices and emission intensity based on historical data from 2015 to 2024. The goal has been to establish a simple and transparent method that can be used in energy system and climate policy analysis. Using statistical transformations such as normalization and median calculations, representative profiles were created at annual, monthly, and daily levels. The results show that the method aligns well with observed data in typical years and captures key seasonal and daily patterns. However, it has limitations during years of high volatility or rapid structural changes. The profiles can be scaled to match various scenarios and are useful in assessing when technologies like heat pumps and solar panels have the highest potential for cost and emission reductions. The thesis demonstrates that simple statistical approaches can provide valuable insights without relying on complex modeling
Degrowth : a post-capitalist approach to heal the metabolic rift
Get PDFThe growth imperative is a core part of our society. Anything produced under this imperative is produced not to create use but to create value and surplus. The objective of this thesis is to understand the logic of this growth imperative and how it has completely halted the collective development of society. Along with this, the thesis delves into how capitalism uses green economic development, efficiency and sustainable technological innovation to satiate the imperative core for infinite accumulation. The thesis mainly uses secondary sources, such as books and papers that give a statistical and factual analysis of the history of the growth imperative, its consequences, and degrowth as a solution.
One of the big issues under the growth imperative is the massive amounts of industrialisation, production and consumption done by the Global North. Their material dependency on the Global South has weakened their societies and has most negatively affected the Earth’s climate. Research reveals that this infinite growth has created a rift between humans and nature, and it's widening constantly. This is what Karl Marx refers to as the metabolic rift. As a way to bind the rift, scholars suggest Degrowth as a post-capitalist approach. This strategy will help to reduce these systemic inequalities by adopting a community-based production approach where production happens for the needs and welfare of the society. Many societies in the past and present have shown the capacity and willingness to take this brave approach and change the core of society. The Lammas, an eco-village in Wales, and Zapatistas in Mexico, show how, through solidarity and with or without government support, communities can be built that are connected to nature and live outside of the growth imperative.
To close the expanding metabolic rift, we need to reevaluate our relationship with nature and understand the ways we are dependent on each other. One way of doing this is transitioning into Degrowth.B-D
A Sea of Opportunities? Socio-Political Acceptance of Norwegian Offshore Wind in a Globalised and Turbulent Energy Landscape
Get PDFNorges havvinds-ambisjoner er i ferd med å gå fra langsiktige planer til konkret implementering. Denne overgangen skjer i en tid preget av økt klimakrise, bekymringer for energisikkerhet, geopolitiske spenninger og vedvarende uenighet knyttet til den norske vindkraftkontroversen på land. Samtidig introduserer havvind nye dimensjoner i debatten om sosial aksept – særlig gjennom økt internasjonal involvering.
Denne oppgaven undersøker hvordan et turbulent energilandskap, kombinert med havvindens globalisering, former den samfunnspolitiske aksepten av teknologien i en norsk kontekst. Selv om havvind ofte antas å ha høyere aksept grunnet mindre visuell påvirkning, avdekker studien et mer komplekst og omstridt landskap. Gjennom abduktiv (abductive) tematisk analyse av ni dybdeintervjuer identifiserer jeg både legitimerende og de-legitimerende narrativer som reflekterer ulike aktørers perspektiver.
Avgjørende er studiens funn av et dypere ontologisk skille – en grunnleggende konflikt i virkelighetsoppfatninger – om hvilken rolle havvind skal spille i det grønne skiftet. Motstand mot havvind handler ikke nødvendigvis om kunnskapsmangel, men springer ut av ulike visjoner for hva energiomstillingen bør innebære. Dette har viktige implikasjoner for politikkutforming: sosial motstand vil sannsynligvis vedvare til tross for bedre kommunikasjon eller institusjonell læring, med mindre disse dypere skillelinjene anerkjennes og adresseres.Norway’s offshore wind journey is transitioning from a long-standing plan to concrete implementation. This shift is materialising amidst heightened climate urgency, concerns over energy security, political tensions and lingering strains from the Norwegian onshore wind controversy. At the same time, offshore wind introduces new dimensions to the social acceptance debate—most notably, increased international involvement.
This thesis explores how a turbulent energy landscape, coupled with the globalisation of offshore wind, is shaping its socio-political acceptance in the Norwegian context. While offshore wind is often assumed to enjoy higher acceptance due to its limited visual impact, this study reveals a more complex and contested reality. Through abductive thematic analysis of nine in-depth interviews, I identify both legitimising and counter-narratives that reflect divergent stakeholder perspectives.
Crucially, the study uncovers a deeper ontological divide—a fundamental clash of worldviews—regarding the role of offshore wind in the green energy transition. Rather than stemming from knowledge deficits, resistance emerges from conflicting visions of what the green energy transition should entail. This has important implications for policy: social resistance is likely to persist despite improved communication or institutional learning, unless these deeper divides are acknowledged and addressed
How Do Segment-Specific Drivers Impact Shipping Stock Returns?
Get PDFThis thesis investigates the conditional risk and return profiles of distinct segments within the global maritime shipping industry. The study analyzes five market-weighted stock portfolios—Drybulk, Tankers, Container, LNGLPG, and Mixed Fleets—over the period June 2013 to February 2025. This study uses Quantile Regression alongside Ordinary Least Squares to examine the impact of segment-specific freight rates, various commodity prices, the market factor (FTSE All World index), the US Dollar Index, and Carbon EUA prices. Value-at-Risk, Expected Shortfall, and scenario analyses are utilized to quantify and differentiate downside risk and upside potential.
The empirical findings reveal significantly different sensitivities to market drivers and distinct conditional risk profiles. The QR analysis reveals that the impact of these drivers varies substantially across different market conditions, highlighting nuances often missed by average-based models. While the market factor is a pervasive driver, its beta is shown to be segment-specific and state-dependent. Segment-specific freight indices (e.g., Baltic Dry Index for Drybulk, Baltic Dirty for Tankers) and certain commodity prices are identified as critical, whereas the US Dollar's impact is only significant for the Container segment. Notably, Carbon EUA prices did not exhibit a consistent, significant negative impact during the study period. VaR and ES metrics confirmed clear distinctions in risk levels and potential returns, with scenario analysis linking these directly to the unique factor exposures of each segment.
This research concludes that a granular, segment-specific, and condition-dependent approach could be beneficial for effective risk management and investment strategies in the maritime sector. The study highlights the value of econometric and risk modeling techniques for achieving a more nuanced understanding, offering vital insights for industry stakeholders, including investors and risk managers