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This work was carried out in the framework of the European Partnership for the Assessment of Risks from Chemicals (PARC) and has received funding from the European Union's Horizon Europe research and innovation programme under Grant Agreement 101057014. L.M. and C.O. were co-funded by the Czech Ministry of Education, Youth and Sports from the Institutional Support of LCDRO and RECETOX Research Infrastructure (LM2023069). The contribution by RISE employees (S.S., L.S., and T.W.) was co-funded by the Swedish Ministry of Climate and Enterprise. E.K.S. and I.T.C. thank the Swedish Research Council FORMAS (Grant 2020-01978) and the Horizon 2020 research and innovation programme (Grant Agreement 101036756; the ZeroPM project) for funding.

Purpose: To evaluate the performance of first trimester maternal serum glycosylated (Sambucus nigra lectin-reactive) fibronectin in prediction of gestational diabetes mellitus (GDM). Methods: In this case–control study, first trimester maternal serum glycosylated fibronectin and fibronectin were measured in 19 women who consequently developed GDM and in 59 control women with normal pregnancy outcomes. Adiponectin was used as a reference protein to evaluate relation of glycoprotein to SNA-lectin-reactive assay format. Samples were taken during gestational weeks 9⁺⁶–11⁺⁶. Data concerning GDM was obtained from the National Institute for Health and Welfare, which records the pregnancy outcomes of all women in Finland. Results: There was no difference in maternal serum glycosylated fibronectin concentrations between women with consequent GDM [447.5 μg/mL, interquartile range (IQR) 254.4–540.9 μg/mL] and control women (437.6 μg/mL, IQR 357.1–569.1 μg/mL). Maternal serum fibronectin levels were significantly lower in GDM group (224.2 μg/mL, IQR 156.8–270.6 μg/mL), compared to the control group (264.8 μg/mL, IQR 224.6–330.6 μg/mL, p < 0.01). There was no difference in assay formats for adiponectin. Conclusion: There was no association between first trimester maternal serum glycosylated (SNA-reactive) fibronectin and GDM.

Dagens samhälle har utvecklats till ett stort globalt system där människan fått en signifikant påverkan på klimatet och miljön. För att nå målet i Parisavtalet är det många sektorer som behöver ställa om sina verksamheter till att bli hållbara. Det gäller i allra högsta grad flygsektorn som har stora utmaningar framför sig när det gäller att minska sitt klimatavtryck. En av möjligheterna för att väsentligt minska flygets klimatpåverkan är att övergå till flygplan som drivs med hjälp av batterier istället för fossila bränslen.I det här projektet undersöks om de tekniska och infrastrukturmässiga förutsättningarna finns för att elflyg ska kunna ersätta den befintliga flygtrafiken mellan Stockholm och Visby och när i tiden en sådan förändring kan ske. Litteraturstudier och intervjuer har använts för att utforska det nuvarande kunskapsläget som är relevant för elflyg inom batteriteknik, elmotorer, aerodynamik samt infrastruktur på de relevanta flygplatserna. Med den utgångspunkten har en matematisk modell använts för att studera om de rådande tekniska förutsättningarna är tillräckliga eller om förbättringar kommer krävas. Det som framkom var att det i teorin är möjligt att tillverka ett elflygplan som kan flyga hela sträckan med befintlig teknik men att utveckling av både batteriteknik och aerodynamik sannolikt kommer krävas när andra aspekter vägs in. Infrastrukturen på flygplatserna är dessutom inte anpassade för elflyg i dagsläget, vilket leder till att det i ett optimistiskt scenario kommer gå att elektrifiera flygtrafiken mellan Stockholm och Visby inom 10 år., Today's society has evolved into a large global system where people have a significant impact on the climate and the environment. To achieve the goal of the Paris Agreement, many sectors need to change their business to become sustainable. This is very much the case for the aviation sector, which has major challenges ahead when it comes to reducing its climate footprint. One of the opportunities to significantly reduce the climate impact of aviation is to switch to aircraft powered by batteries instead of fossil fuels. This project examines whether the technical and infrastructure conditions are in place for electric aircraft to replace the existing air traffic between Stockholm and Visby and when such a change can occur in time. Literature studies and interviews have been used to explore the current state of knowledge relevant to electric aviation within battery technology, electric motors, aerodynamics and infrastructure at the relevant airports. Based on this, a mathematical model has been used to study whether the current technical conditions are sufficient or if improvements will be required. What emerged was that, in theory, it is possible to produce an electric aircraft that can fly the entire distance with existing technology, but that development of both battery technology and aerodynamics is likely to be required when other aspects are taken into account. The infrastructure at the airports is also not adapted for electric flights yet, which means that in an optimistic scenario it will take up to 10 years before air traffic can be fully electrified between Stockholm and Visby.

Dagens samhälle har utvecklats till ett stort globalt system där människan fått en signifikant påverkan på klimatet och miljön. För att nå målet i Parisavtalet är det många sektorer som behöver ställa om sina verksamheter till att bli hållbara. Det gäller i allra högsta grad flygsektorn som har stora utmaningar framför sig när det gäller att minska sitt klimatavtryck. En av möjligheterna för att väsentligt minska flygets klimatpåverkan är att övergå till flygplan som drivs med hjälp av batterier istället för fossila bränslen.I det här projektet undersöks om de tekniska och infrastrukturmässiga förutsättningarna finns för att elflyg ska kunna ersätta den befintliga flygtrafiken mellan Stockholm och Visby och när i tiden en sådan förändring kan ske. Litteraturstudier och intervjuer har använts för att utforska det nuvarande kunskapsläget som är relevant för elflyg inom batteriteknik, elmotorer, aerodynamik samt infrastruktur på de relevanta flygplatserna. Med den utgångspunkten har en matematisk modell använts för att studera om de rådande tekniska förutsättningarna är tillräckliga eller om förbättringar kommer krävas. Det som framkom var att det i teorin är möjligt att tillverka ett elflygplan som kan flyga hela sträckan med befintlig teknik men att utveckling av både batteriteknik och aerodynamik sannolikt kommer krävas när andra aspekter vägs in. Infrastrukturen på flygplatserna är dessutom inte anpassade för elflyg i dagsläget, vilket leder till att det i ett optimistiskt scenario kommer gå att elektrifiera flygtrafiken mellan Stockholm och Visby inom 10 år., Today's society has evolved into a large global system where people have a significant impact on the climate and the environment. To achieve the goal of the Paris Agreement, many sectors need to change their business to become sustainable. This is very much the case for the aviation sector, which has major challenges ahead when it comes to reducing its climate footprint. One of the opportunities to significantly reduce the climate impact of aviation is to switch to aircraft powered by batteries instead of fossil fuels. This project examines whether the technical and infrastructure conditions are in place for electric aircraft to replace the existing air traffic between Stockholm and Visby and when such a change can occur in time. Literature studies and interviews have been used to explore the current state of knowledge relevant to electric aviation within battery technology, electric motors, aerodynamics and infrastructure at the relevant airports. Based on this, a mathematical model has been used to study whether the current technical conditions are sufficient or if improvements will be required. What emerged was that, in theory, it is possible to produce an electric aircraft that can fly the entire distance with existing technology, but that development of both battery technology and aerodynamics is likely to be required when other aspects are taken into account. The infrastructure at the airports is also not adapted for electric flights yet, which means that in an optimistic scenario it will take up to 10 years before air traffic can be fully electrified between Stockholm and Visby.

Chemical reactors are a part of modern industry and the catalytic tubular fixed bed reactor examined in this work is an important reactor for chemicals production. In this work two different types of models for the reactor are studied; a pseudohomogeneous model and a heterogeneous model. The goal is to find differences in behaviour between these two types of reactor models and explain these. In a real reactor there exists two phases, a solid catalyst and a fluid reactant. Both these phases are in the pseudohomogeneous model treated as a single phase, a pseudofluid. In the heterogeneous model the two phases are treated separately. When comparing these types of models a few structural differences exist, void fraction, heat exchange between two phases, and heat dispersion in the phases, and all of these will affect the behaviour of the models differently. The models are studied using bifurcation analysis and linear analysis. Bifurcation theory is used to find and track different solutions depending on a certain parameter and to get a good overall picture of a system’s solutions and their type, steady state or sustained oscillation. Linear analysis is used to study linearization around a specific solution and to determine stability and frequency dependency. It is found that the concept of void fraction in the reactor model affects the behaviour only as a time scaling, while the concept of interfacial heat exchange affects the stability. The distribution of heat dispersion between phases has a significant impact on the reaction behaviour. Feedback is determined as the main cause for instabilities and oscillative solutions.

Chemical reactors are a part of modern industry and the catalytic tubular fixed bed reactor examined in this work is an important reactor for chemicals production. In this work two different types of models for the reactor are studied; a pseudohomogeneous model and a heterogeneous model. The goal is to find differences in behaviour between these two types of reactor models and explain these. In a real reactor there exists two phases, a solid catalyst and a fluid reactant. Both these phases are in the pseudohomogeneous model treated as a single phase, a pseudofluid. In the heterogeneous model the two phases are treated separately. When comparing these types of models a few structural differences exist, void fraction, heat exchange between two phases, and heat dispersion in the phases, and all of these will affect the behaviour of the models differently. The models are studied using bifurcation analysis and linear analysis. Bifurcation theory is used to find and track different solutions depending on a certain parameter and to get a good overall picture of a system’s solutions and their type, steady state or sustained oscillation. Linear analysis is used to study linearization around a specific solution and to determine stability and frequency dependency. It is found that the concept of void fraction in the reactor model affects the behaviour only as a time scaling, while the concept of interfacial heat exchange affects the stability. The distribution of heat dispersion between phases has a significant impact on the reaction behaviour. Feedback is determined as the main cause for instabilities and oscillative solutions.