D-dimer for diagnosis and risk assessment of first and recurrent venous thromboembolism

Venøs tromboembolisme (VTE) er en samlebetegnelse på dyp venetrombose (DVT) og lungeemboli. D-dimer, en blodprøve for koagulasjon og fibrinolyse, har vært en sentral del av VTE-diagnostikken i flere tiår. Blodprøven D-dimer har flere bruksområder og kan dermed reflektere ulike aspekter ved VTE. I denne avhandlingen har vi undersøkt i) om det er trygt og effektivt å bruke D-dimer uten samtidig bruk av risikoskår for å utelukke DVT hos pasienter med mistenkt DVT, ii) sammenhengen mellom D-dimer-nivå og førstegangs VTE og hvordan overvekt og inflammasjon påvirker denne sammenhengen, og iii) betydningen av D-dimer målt ved diagnosetidspunktet på risikoen for residiverende VTE. I artikkel I inkluderte vi pasienter henvist til Universitetssykehuset Nord-Norge med mistenkt DVT. Basert på de faktiske DVT-diagnosene ved det første besøket eller i løpet av de påfølgende tre månedene, estimerte vi hvor mange DVTer som ville ha blitt oversett (udiagnostisert) hvis D-dimer alene hadde vært den diagnostiske strategien. I artikkelen fant vi at D-dimer alene er trygt for å utelukke proksimal DVT hos ikke-innlagte pasienter og at denne strategien har potensiale til å forenkle og øke effektiviteten av utredningen. I artikkel II utførte vi en befolkningsbasert nøstet kasus-kontroll studie med VTE-kasuser og tilhørende matchende kontroller fra Tromsøundersøkelsen. D-dimer ble målt i blodprøver som var tatt ved inklusjon og odds ratioer for VTE ble beregnet utfra D-dimer-kvartiler. I studien fant vi at høyere D-dimer ved inklusjon er assosiert med økt risiko for førstegangs VTE, og at D-dimer-nivåene delvis reflekterer underliggende tilstander relatert til overvekt og inflammasjon. I artikkel III inkluderte vi pasienter med førstegangs symptomatisk VTE fra TROLL-studien ved Sykehuset Østfold. Alle tilfeller av residiverende VTE i oppfølgingstiden ble registrert, og den samlede insidensen av residiv ble estimert etter henholdsvis D-dimer ≤1900 ng/mL (≤25 persentilen) og >1900 ng/mL på diagnosetidspunktet. I studien fant vi at lav D-dimer på diagnosetidspunktet trolig kan identifisere pasienter med lav risiko for residiverende VTE. Hos disse kan blodfortynnende behandling trolig stoppes etter den første behandlingsfasen. Funnene i denne avhandlingen viser bredden i bruken av D-dimer og dens viktige plass både i diagnostikken av førstegangs DVT og prediksjonen av residiverende hendelser. De foreslåtte strategiene i avhandlingen har potensiale til å forbedre dagens håndtering av VTE

Student conceptions of religion : Ethics and cosmology as essential elements

This abductively oriented empirical article investigates the use of ‘essences’ and ‘central themes’ in student-made ‘religions’ created as an optional written assignment among Norwegian upper secondary school students. The article aims to add to the discussions on how ‘religion’ is conceptualised and taught, with a particular focus on religious studies and religious didactics. It describes the coding and analysis process and showcases the data. The results are discussed, with an emphasis on the abductively produced categories of ethics and cosmology, chosen due to their prevalence and depth in the data. The religions are compared to Ninian Smart’s dimensional model of religion, used as a method to describe which parts of ‘religion’ have been included or omitted in the student-made religions. Lastly, I discuss how educators might go forward and suggest a didactics-based discussion on how to deal with religious experience and ritual in the classroom.publishedVersio

A measurement of the extent of the color-sensitive areas of the retina and of the wavelengths of light stimulating the respective receptor mechanisms

The interest of the writer was directed toward the phenomena of color vision in 1927 as a result of attending concurrently two courses in the University of California touching upon the subject, but treating it quite differently with results far from mutually consistent. Prof. R. S. Minor, in his course on physical optics, discussed color vision from the physicist’s standpoint, making use of the Young-Helmholtz theory; while Prof. G. M. Stratton gave the psychological treatment, based upon the Ladd-Franklin theory, as a part of his general psychology. Several of the more obviously points of conflict impressed the writer so strongly that he was led to bring the matter to the attention of the professors concerned. At the resulting conference between the two, a number of demonstrative experiments were performed and from the discussion of these in terms of the various theories the writer profited much. However, many facts remained unreconciled, so the writer resolved to investigate the subject further should opportunity present itself. The following research is a beginning of that study

Overturning in the Nordic Seas from 2002 to 2017 in the Arctic Subpolar gyre sTate Estimate

A data-constrained, medium-resolution coupled sea ice-ocean state estimate, the Arctic Subpolar gyre sTate Estimate, is evaluated in the Nordic Seas. The state estimate is dynamically and kinematically consistent, and has a nominal resolution of 1/3 degree, corresponding to 16 km in the Nordic Seas. It is biased low in density throughout the domain, most prominently in the Greenland and Iceland Seas where the water column above 1000 m is both too warm and too fresh. The deepest mixed layers are found in the West Spitsbergen Current instead of in the Greenland Sea. The overflow water spilling across the Greenland-Scotland Ridge is too light, and constitute a smaller volume than observations from the same period indicate. Other main features of the Nordic Seas are generally well reproduced. The state estimate is used to explore the overturning in the Nordic Seas, in particular to quantify the rate of dense-water production in each basin, and investigate the factors influencing the overturning. In the state estimate, the densest water of the Nordic Seas is formed in the Greenland Sea, and the near-surface salinity greatly influences the its formation. The production rate of dense water is too low to realistically simulate the overflow across the Greenland-Scotland Ridge, a bias that contributes to a weakened AMOC. In light of the expected increase in freshwater loading due to global warming, the Arctic Subpolar Gyre sTate Estimate may be more representative of the overturning in the Nordic Seas in a future warmer climate.Masteroppgave i meteorologi og oseanografiGEOF399MAMN-GEO

Is There Gold in Green? A Modified Perspective of Income Developments in Active Agriculture

This thesis seeks to answer how active agricultural incomes in Norway have evolved from 1970 to 2021, by modifying the aggregated account. The calculation of the farmer’s income has been a contentious debate for a longer period, and our aim is for this thesis to calculate a more realistic development model for agricultural incomes. By utilizing agricultural statistics from various sources, we present the modified aggregated account, as outlined by the Grytten Committee in 2022, spanning from 1970 to 2021. Our findings indicate that active farmers generally have a lower pre-tax income when applying this framework compared to the original aggregated account. Our objective is not to provide a specific figure for the earnings of Norwegian farmers but rather to examine how income has evolved over time. We apply the Hodrick-Prescott filter to several time series to compare developments in the cyclical components over time. For agricultural income and economic cycles, we find no clear correlations. This is partly due to agricultural incomes being subject to extensive support schemes and market regulations. Furthermore, we identify a positive relationship between agricultural incomes and agricultural production. This aligns with our assumptions, as a portion of the income is directly tied to production. We also demonstrate that fluctuations between incomes and subsidies often exhibit close covariance, although not universally. The inconsistency stems from excessive subsidies leading to overproduction and subsequently reduced income, and due to subsidies serving multiple purposes. Our findings reveal a growing divergence between NIBIO’s and our modified account over time, but also demonstrates the independence of income from broader economic fluctuations. Thanks to strong support systems and favorable market regulations for agriculture, incomes remain relatively insulated from economic cycles and, to some extent, also production fluctuations. Nevertheless, production will still have a certain correlation with incomes, as a portion of the earnings is directly linked to the sale of goods.nhhma

Sørlandets industri: Et sveip over 400 år.

publishedVersio

Optimizing agents with genetic programming : an evaluation of hyper-heuristics in dynamic real-time logistics

Dynamic pickup and delivery problems (PDPs) require online algorithms for managing a fleet of vehicles. Generally, vehicles can be managed either centrally or decentrally. A common way to coordinate agents decentrally is to use the contract-net protocol (CNET) that uses auctions to allocate tasks among agents. To participate in an auction, agents require a method that estimates the value of a task. Typically this method is an optimization algorithm. Recently, hyper-heuristics has been proposed for automated design of heuristics. Two properties of automatically designed heuristics are particularly promising: 1) a generated heuristic computes quickly, it is expected therefore that hyper-heuristics heuristics perform especially well for urgent problems, and 2) by using simulationbased evaluation, hyper-heuristics can learn from the past and can therefore create a ‘rule of thumb’ that anticipates situations in the future. In the present paper we empirically evaluate whether hyper-heuristics, more specifically genetic programming (GP), can be used to improve agents decentrally coordinated via CNET. We compare several GP settings and compare the resulting heuristic with existing centralized and decentralized algorithms on a dynamic PDP dataset with varying levels of dynamism, urgency, and scale. The results indicate that the evolved heuristic always outperforms the optimization algorithm in the decentralized MAS and often outperforms the centralized optimization algorithm. Our paper shows that designing MASs using genetic programming is an effective way to obtain competitive performance compared to traditional operational research approaches. These results strengthen the relevance of decentralized agent based approaches in dynamic logistics