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Thiamin is an essential water-soluble B vitamin known for its wide range of metabolic functions and antioxidant properties. Over the past decades, reproductive failures induced by thiamin deficiency have been observed in several salmonid species worldwide, but it is unclear why this micronutrient deficiency arises. Few studies have compared thiamin concentrations in systems of salmonid populations with or without documented thiamin deficiency. Moreover, it is not well known whether and how thiamin concentration changes during the marine feeding phase and the spawning migration. Therefore, samples of Atlantic salmon (Salmo salar) were collected when actively feeding in the open Baltic Sea, after the sea migration to natal rivers, after river migration, and during the spawning period. To compare populations of Baltic salmon with systems without documented thiamin deficiency, a population of landlocked salmon located in Lake Vanern (Sweden) was sampled as well as salmon from Norwegian rivers draining into the North Atlantic Ocean. Results showed the highest mean thiamin concentrations in Lake Vanern salmon, followed by North Atlantic, and the lowest in Baltic populations. Therefore, salmon in the Baltic Sea seem to be consistently more constrained by thiamin than those in other systems. Condition factor and body length had little to no effect on thiamin concentrations in all systems, suggesting that there is no relation between the body condition of salmon and thiamin deficiency. In our large spatiotemporal comparison of salmon populations, thiamin concentrations declined toward spawning in all studied systems, suggesting that the reduction in thiamin concentration arises as a natural consequence of starvation rather than to be related to thiamin deficiency in the system. These results suggest that factors affecting accumulation during the marine feeding phase are key for understanding the thiamin deficiency in salmonids.

Vitamin B-1 (thiamin) is primarily produced by bacteria, phytoplankton and fungi in aquatic food webs and transferred to higher trophic levels by ingestion. However, much remains unknown regarding the dynamics this water-soluble, essential micronutrient; e.g. how it relates to macronutrients (carbon, nitrogen and phosphorous). Nutrient limitation has been found to be related to periods of thiamin deficiency as well as in models. Hence, thiamin transfer to copepods from three phytoplankton species from different taxa was investigated, along with the effect of various nutrient regimes on thiamin content. Nutrient levels did not affect thiamin content of phytoplankton nor the transfer to copepods. Instead, phytoplankton displayed species-specific thiamin and macronutrient contents and whilst a higher thiamin content in the prey lead to higher levels in copepods, the transfer was lower for Skeletonema compared to Dunaliella and Rhodomonas. In all, thiamin transfer to copepods is not only dependent on thiamin content of the prey, but also the edibility and/or digestibility is of importance. Thiamin is essential for all organisms, and this study offers insights into the limited effect of macronutrients on the dynamics and transfer of thiamin in the aquatic food webs.

Although free-living (FL) and particle-attached (PA) bacteria are recognized as ecologically distinct compartments of marine microbial food-webs, few, if any, studies have determined their dynamics in abundance, function (production, respiration and substrate utilization) and taxonomy over a yearly cycle. In the Baltic Sea, abundance and production of PA bacteria (defined as the size-fraction >3.0 mu m) peaked over 3 months in summer (6 months for FL bacteria), largely coinciding with blooms of Chitinophagales (Bacteroidetes). Pronounced changes in the growth efficiency (range 0.05-0.27) of FL bacteria (defined as the size-fraction <3.0 mu m) indicated the magnitude of seasonal variability of ecological settings bacteria experience. Accordingly, 16S rRNA gene analyses of bacterial community composition uncovered distinct correlations between taxa, environmental variables and metabolisms, including Firmicutes associated with elevated hydrolytic enzyme activity in winter and Verrucomicrobia with utilization of algal-derived substrates during summer. Further, our results suggested a substrate-controlled succession in the PA fraction, from Bacteroidetes using polymers to Actinobacteria and Betaproteobacteria using monomers across the spring to autumn phytoplankton bloom transition. Collectively, our findings emphasize pronounced seasonal changes in both the composition of the bacterial community in the PA and FL size-fractions and their contribution to organic matter utilization and carbon cycling. This is important for interpreting microbial ecosystem function-responses to natural and human-induced environmental changes.

Thiamin (vitamin B1) is primarily produced by bacteria and phytoplankton in aquatic food webs and transferred by ingestion to higher trophic levels. However, much remains unknown regarding production, content and transfer of this water-soluble, essential micronutrient. Hence, the thiamin content of six phytoplankton species from different taxa was investigated, along with the effect of thiamin amendment on thiamin content. Furthermore, thiamin transfer to copepods was estimated in feeding experiments. Prey type, not phytoplankton thiamin content per se, was the most important factor for the transfer of thiamin, as it was lowest from filamentous Cyanophyceae and highest from more easily ingested prey like Dunaliella tertiolecta and Rhodomonas salina. Cyanophyceae had the highest thiamin content of the investigated species, eightfold higher than the lowest. Phytoplankton varied in thiamin content related to the supply of thiamin, where thiamin addition enabled higher thiamin content in some species, while copepod thiamin content was less variable. In all, thiamin transfer is not only dependent on the prey thiamin content, but also the edibility and/or digestibility is of importance. Thiamin is essential for all organisms, and this study constitutes an important building block to understanding the dynamics and transfer of thiamin in the aquatic food web.

Healthcare might seem like it is a purely medical issue. Nothing could be further from the truth. Both politics, law and the economy are all closely tied to healthcare. In this thesis I analyze the sensitive topic of healthcare through a critical understanding of the European and Swedish political economies from the 1970s until today. Europe serves as the broad picture, while Swedish healthcare policy and governance help exemplify how abstract ideas of the economy and politics become embedded in our day-to-day actions. Emphasis is put on explaining the policy changes of the Social Democratic Party in Sweden. To my help I use Critical Discourse Analysis on reports, investigations and legal texts, as well as material from interviews with two medical professionals. In addition to this, I triangulate the results by studying second hand material on political and economic conditions in Europe and Sweden. I show how the Social Democrats have introduced New Public Management-reforms as a way to manage the public administration more efficiently. Furthermore, New Public Management-reforms in healthcare are analyzed as an attempt to stabilize a fundamentally unstable transnational political economy by opening a "healthcare market" to attract capital and capitalists.

Marine bacterioplankton are essential in global nutrient cycling and organic matter turnover. Time-series analyses, often at monthly sampling frequencies, have established the paramount role of abiotic and biotic variables in structuring bacterioplankton communities and productivities. However, fine-scale seasonal microbial activities, and underlying biological principles, are not fully understood. We report results from four consecutive years of high-frequency time-series sampling in the Baltic Proper. Pronounced temporal dynamics in most investigated microbial variables were observed, including bacterial heterotrophic production, plankton biomass, extracellular enzyme activities, substrate uptake rate constants of glucose, pyruvate, acetate, amino acids, and leucine, as well as nutrient limitation bioassays. Spring blooms consisting of diatoms and dinoflagellates were followed by elevated bacterial heterotrophic production and abundances. During summer, bacterial productivity estimates increased even further, coinciding with an initial cyanobacterial bloom in early July. However, bacterial abundances only increased following a second cyanobacterial bloom, peaking in August. Uptake rate constants for the different measured carbon compounds varied seasonally and inter-annually and were highly correlated to bacterial productivity estimates, temperature, and cyanobacterial abundances. Further, we detected nutrient limitation in response to environmental conditions in a multitude of microbial variables, such as elevated productivities in nutrient bioassays, changes in enzymatic activities, or substrate preferences. Variations among biotic variables often occurred on time scales of days to a few weeks, yet often spanning several sampling occasions. Such dynamics might not have been captured by sampling at monthly intervals, as compared to more predictable transitions in abiotic variables such as temperature or nutrient concentrations. Our study indicates that high resol

Thiamin (vitamin B1) is mainly produced by bacteria and phytoplankton and then transferred to zooplankton and higher trophic levels but knowledge on the dynamics of these processes in aquatic ecosystems is lacking. Hence, the seasonal variation in thiamin content was assessed in field samples of copepods and in pico-, nano- and micro-plankton of two size classes (0.7–3 µm and > 3 µm) collected monthly in the Baltic Sea during 3 years and in the Skagerrak during 1 year. Copepods exhibited species-specific concentrations of thiamin and Acartia sp. had the highest carbon-specific thiamin content, at both locations. Even members of the same genus, but from different systems contained different levels of thiamin, with higher thiamin content per specimen in copepods from the Skagerrak compared to congeners from the Baltic Sea. Furthermore, our results show that the small plankton (0.7–3 µm) had a higher carbon-specific thiamin content compared to the large (> 3 µm). Additionally, there was a large seasonal variation and thiamin content was highly correlated comparing the two size fractions. Finally, there was an overall positive correlation between thiamin content in copepods and plankton. However, for periods of high thiamin content in the two size fractions, this correlation was negative. This suggests a decoupling between thiamin availability in pico-, nano- and micro-plankton and zooplankton in the Baltic Sea. Knowledge about concentrations of this essential micronutrient in the aquatic food web is limited and this study constitutes a foundation for further understanding the dynamics of thiamin in aquatic environments.

Vitamin B-1 is an essential exogenous micronutrient for animals. Mass death and reproductive failure in top aquatic consumers caused by vitamin B-1 deficiency is an emerging conservation issue in Northern hemisphere aquatic ecosystems. We present for the first time a model that identifies conditions responsible for the constrained flow of vitamin B-1 from unicellular organisms to planktivorous fishes. The flow of vitamin B-1 through the food web is constrained under anthropogenic pressures of increased nutrient input and, driven by climatic change, increased light attenuation by dissolved substances transported to marine coastal systems. Fishing pressure on piscivorous fish, through increased abundance of planktivorous fish that overexploit mesozooplankton, may further constrain vitamin B-1 flow from producers to consumers. We also found that key ecological contributors to the constrained flow of vitamin B-1 are a low mesozooplankton biomass, picoalgae prevailing among primary producers and low fluctuations of population numbers of planktonic organisms.

The world is striving to achieve significant carbon dioxide emission reductions within the near future, and the maritime industry is no exception. The International Maritime Organization has set clear emission reduction targets, while ship owners endeavour financial profit. Energy efficiency has become the golden mean, satisfying both parties. The internal combustion engines are the largest thermal processes regarding energy and thus naturally come with the greatest heat losses. Recovering and finding use for this heat improves the energy efficiency. The heat recovery is done by absorbing engine heat into a hot water flow, often referred to as the waste heat recovery circuit, and by connecting heat consumers to this circuit. In some cases, excess heat is available and additional energy efficiency improving thermal processes, such as an organic Rankine cycle, may be connected to the circuit. The opposite case occurs when there is not sufficient heat available. The flow must, therefore, be boosted using steam, which increases the fuel consumption. In some cases, the heat generation varies from being abundant to being insufficient depending on the vessel speed. In this case, a heat storage would allow storing heat for later use, thus reducing the amount of steam boosting required. Dimensioning possible additional heat consuming applications and heat storages is a complicated process. This thesis introduces a dynamic simulation tool created, which allows an accurate thermodynamic analysis of the waste heat recovery circuit. It eases the planning and dimensioning task of these energy efficiency improving equipment. The simulation tool was used to make a case study on a large cruise ship. An organic Rankine cycle with a 150kW electrical capacity showed enormous potential on the case vessel. The annual operating expenses were reduced by 76800€ and the emissions by 1.83%. Improved results were obtained by increasing the organic Rankine cycle capacity, at the cost of a lower, Maailmalla pyritään lähitulevaisuudessa merkittäviin hiilidioksidipäästöjen vähennyksiin, eikä meriteollisuus ole poikkeus. Kansainvälinen merenkulkujärjestö on asettanut selkeät päästövähennystavoitteet, laivan omistajat puolestaan pyrkivät taloudelliseen voittoon. Energiatehokkuudesta on tullut kultainen keskitie, joka tyydyttää molemmat osapuolet. Polttomoottorit ovat laivan suurimmat lämpövoimaprosessit energian suhteen ja täten luonnollisesti myös suurimmat hukkalämmön lähteet. Hukkalämmön talteenotto ja hyödyntäminen parantavat energiatehokkuutta. Talteenotto voidaan toteuttaa siirtämällä moottorin tuottama lämpö vesivirtaukseen, niin sanottuun lämmön talteenottopiiriin, ja kytkemällä lämmönkuluttajia kyseiseen piiriin. Joissain tapauksissa on käytettävissä ylimääräistä lämpöä, jolloin energiatehokkuutta parantavia lämpövoimaprosesseja, kuten orgaaninen Rankine-kierto, voidaan kytkeä piiriin. Päinvastaisessa tilanteessa lämpöä ei ole tarpeeksi. Piirin virtausta on tällöin lämmitettävä vesihöyryllä, joka nostaa polttoaineenkulutusta. Laivan nopeus vaikuttaa lämmön tuotannon määrään ja täten riittävyyteen. Tällöin ylimääräisen lämmön varastointi myöhempää käyttö varten pienentäisi vesihöyrylämmityksen tarvetta. Mahdollisten energiatehokkuutta parantavien lämpövoimaprosessien ja lämpövarastojen mitoitus on monimutkainen tehtävä. Tämä diplomityö esittelee sitä varten laaditun dynaamisen simulointityökalun, joka mahdollistaa lämmön talteenottopiirin tarkan termodynaamisen tarkastelun. Se helpottaa energiatehokkuutta parantavien laitteiden suunnittelua ja mitoitusta. Simulointityökalua sovellettiin suurehkon esimerkkiristeilijän tarkasteluun. Orgaanisella Rankine-kierrolla, jolla on 150kW sähköntuotantokapasiteetti näyttää olevan suuri potentiaali risteilijässä. Vuosittaiset toimintakustannukset vähenivät 76 800€:lla ja päästöt 1.83%:lla. Suuremmat hyödyt saavutettiin kasvattamalla orgaanisen Rankine-kierron kapasiteettia, jolloin sen käyttöaste laski. Lämpövarasto

Hur man väljer att driva och bygga upp en internationell rymdstation är lång ifrån självklart. Det samarbete som finns den nuvarande IS- stationen är vad vår uppsats behandlar. Hur relationen ser ut mellan det transnationella forskarsamhället och de nationella egenintresserna från den amerikanska och ryska staten har påverkat, samt fortsätter att påverka ISS än idag. Genom att göra två tidsnedslag, ett vid tiden när det nuvarande avtalet skrevs, 1998. Samt ett andra tidsnedslag närmre nutid för att se hur samarbetet klarat sin kanske svåraste prövning med Ukraina-krisen och Rysslands annektering av Krim. Resultatet visar att det finns en epistemic community, transnationellt forskarsamhälle, med andra målsättningar än staterna. Forskargemenskapen inom ISS vill hellre prioritera forskningsframsteg framför de nationella egenintresserna. Vad som är troligt är också forskarsamhällets stora influens över beslutsfattarna, exempelvis så stöds det här antagandet av planerna på att bygga en ny rymdstation under 2020-talet trots politiska svårigheter.