Publikationer från Uppsala Universitet
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Make it flow from solid to liquid : Redox-active electrofluids for intrinsically stretchable batteries
No full textHigh-capacity stretchable batteries are crucial for next-generation wearables to enable long-term operation and mechanical conformability with the human user. In existing stretchable battery designs, increasing the active material to yield higher capacity often leads to thicker and stiffer solid electrodes with poor mechanical properties. Here, we present a concept that transfers the physical property of a battery electrode from a conventional solid into a fluid state. The mechanical and electrochemical properties of the electrode rely on the viscosity of fluids rather than Young's modulus of solids. Fluids conform easily into any shape with minimal force, making them intrinsically deformable. This decouples the electrochemical and mechanical property of the redox-active electrofluid, leading to higher capacities with more active material loading without stiffening the cell. The cell showed excellent capacity retention over 500 charge-discharge cycles and mechanical robustness up to 100% strain. Our work provides a technological solution for stretchable batteries that balances capacity and mechanical performance
Exceptional high-temperature corrosion resistance of multi-component alloys via modulating Al and Nb
No full textThe chemical compatibility of metallic materials with thermal transfer/storage media, which often involves aggressive working conditions (i.e., high-temperature, corrosive environments), challenges the safe operations advanced and sustainable energy-related infrastructures. Here, we report the corrosion-oxidation behaviors three multi-component alloys (MCAs) when exposed to a corrosive heavy-liquid metal condition (i.e., molten at 650 degrees C with 10-6 wt% oxygen dissolved). The two compositions, Al0.36Cr0.67FeNi0.98 (HAl11) Al0.27Cr0.71FeNi1.16Nb0.17 (HAl8Nb), show excellent corrosion-resistance via passivating a protective oxide on the alloy surface. Further characterizations of the oxide layers differentiate their corrosion-oxidation mechanisms: a protective Al2O3 oxide layer (with Cr and Fe segregation outmost) formed on HAl11 and a duplex oxide layer (outward growth of FeCr2O4/Cr2O3 layer plus inward growth of an Al2O3 layer) with internal oxidation HAl8Nb. Adding Nb improved the corrosion-oxidation resistance ("Nb-doping effect") by enhancing the outward diffusion of metallic elements and promoting the rapid establishment of an alumina scale. Besides, the presence of AlNbO4, which was predicted by thermodynamics calculation, lying between the spinel and Al2O3 formation, was also confirmed by experimental observations. Our findings advance the mechanistic understanding of MCAs' performances in extreme conditions and provide novel strategies for designing corrosion-resistant alloys geting aggressive application environments
Flerspråkighet i förskolan : En kvalitativ studie om förskolläares strategier och uppfattningar för att stödja flerspråkiga barns språkutveckling
No full textDenna studie undersöker hur förskollärare uppfattar flerspråkighet samt vilka strategier och arbetssätt de använder för att främja språkutveckling hos flerspråkiga barn i mångkulturella förskolor. Syftet är att bidra till en fördjupad förståelse för hur interaktion med flerspråkiga barn sker och vilka strategier som används för detta.Studien bygger på en kvalitativ forskningsansats och består av två delstudier. Delstudie 1 bygger på observationer av fem legitimerade förskollärares interaktioner med flerspråkiga barn, medan delstudie 2 baseras på semistrukturerade intervjuer med samma förskollärare. Resultaten av observationerna visar bland annat att förskollärarna använder en rad strategier för interaktion med flerspråkiga barn i vardagliga situationer, såsom kroppsspråk, bildstöd, frågor, och upprepningar. Resultatet av intervjuerna visar att förskollärarna har en medveten och reflekterande syn på flerspråkighet som en resurs i förskolans verksamhet. Förskollärarna beskriver hur de i sin praktik använder språkliga artefakter som grund för att stärka flerspråkiga barns språk. Arbetssätt som involverar, samverkan med vårdnadshavare, inkluderande aktiviteter lyfts fram som viktiga. En av slutsatserna i denna studie är att förskollärarna i hög grad betraktar flerspråkighet som en tillgång i förskolans verksamhet. Genom användning av olika strategier för interaktion såsom kroppsspråk, bildstöd och språkalternering, skapas förutsättningar för en inkluderande och språkstimulerande miljö där de flerspråkiga barnens hela språkliga repertoar ges utrymme. Samtidigt är en annan slutsats i denna studie att förskollärarna är medvetna om de utmaningar som kan uppstå med flerspråkighet, som exempelvis svårigheten att kommunicera med flerspråkiga barn. Trots detta framträder en stark vilja hos samtliga förskollärare att bekräfta flerspråkiga barns språkliga och kulturella bakgrunder och att utveckla arbetssätt som leder till språkutveckling.
Hans Christoffer von Rohrs många äktenskap och Åkersteins genealogiska opålitlighet : En källkritisk granskning
No full textUppgifterna i den genealogiska litteraturen om Hans Christoffer vonRohr, nr 807, den yngste av tre bröder som 1672 naturaliserades ochintroducerades på Riddarhuset, är motsägelsefulla och uppvisarmånga besynnerligheter. Särskilt de många äktenskapen och barnen,där han skall ha varit gift hela sju gånger, varav sex av äktenskapenskall ha följt på varandra i tät följd under en 20-årsperiod, är iögonfallande.Syftet med föreliggande artikel är att källkritiskt utreda dennakomplicerade härva och bedöma trovärdigheten av de olika uppgifterna,för att fastställa vilka uppgifter som kan anses vara tillförlitligaoch vilka uppgifter som bör strykas ur den genealogiska litteraturen.För detta syfte görs en källkritisk genomgång av uppgifterna om vonRohr och hans uppgivna hustrur och barn i den genealogiska litteraturen,härleder ursprunget till dessa och undersöker i vilken mån de harstöd i samtida primärkällor eller tvärtom strider mot vad som meddelasav dessa. Föreliggande artikel visar att von Rohr endast var gift tregånger, och att grundorsaken till de många besynnerligheterna i denvon Rohrska genealogin står att finna i Åkersteins genealogier, där direktpåhittade namn, födelse-, vigsel- och dödsdatum för såväl vonRohr själv som hans hustrur och barn har vilselett senare tiders genealoger,vilka i sin tur har fått ta till olika typer av ad hoc-lösningar,såsom att stoppa in okända hustrur i de genealogiska tabellerna, för attfå de många motsägelsefulla uppgifterna att gå ihop. Vi redovisar härvidäven nya uppgifter om von Rohrs tredje hustrus ursprung samt tidigareej redovisade barn
Smoking as a risk factor for rheumatoid arthritis : predominant association with IgA autoantibodies - comprehensive analysis of anti-modified protein antibodies with smoking and genetic risk factors in rheumatoid arthritis
No full textBackground Rheumatoid arthritis (RA) is an autoimmune disease characterized by the presence of autoantibodies against modified proteins, known as anti-modified protein autoantibodies (AMPAs). While the relationship between different AMPA isotypes and various risk factors remains poorly understood, investigating this association is important for a deeper understanding of RA pathophysiology. Smoking, has its primary effects in the lungs, and it remains unclear whether smoking is preferentially linked to specific AMPA isotypes, such as IgA, which could suggest a mucosal origin. Therefore, we set out to investigate the association between smoking, genetic risk factors for RA, and the presence of specific AMPA isotypes, particular IgA. Methods In 618 RA patients, anti-citrullinated protein antibodies (ACPA-) and anti-acetylated protein antibodies (AAPA-) IgA, -IgG and -IgM and RF-IgA and -IgM were measured by ELISA. Associations with genetic risk factors, smoking and autoantibodies were assessed with logistic regression analysis. For replication, a comprehensive meta-analysis incorporating 3309 RA patients was performed. Results Smoking was primarily associated with IgA AMPA, with associations that prevailed after correcting for the concurrent presence of AMPA IgG (ACPA-IgA OR 1.89 [1.14-3.12], AAPA-IgA 2.30 [1.35-3.94]). To further substantiate these results, we performed a meta-analysis of 3309 RA patients and observed that smoking was again predominantly associated with the combined presence of ACPA-IgA in addition to ACPA-IgG (OR 2.05 [1.69-2.49], p < 0.001) versus the single presence of ACPA-IgG (OR 1.18 [0.97-1.44], p = 0.11). A gene-environment interaction between the most important genetic risk factor for RA (the HLA shared epitope alleles) and smoking was only seen in patients that were both ACPA-IgG and ACPA-IgA positive, but not in patients who were only positive for ACPA-IgG. Conclusion These data provide a pivotal refinement of existing knowledge regarding risk factor associations for RA and lend novel support to the hypothesis that smoking may exert its effect on RA by the induction of local (auto)immune responses at mucosal sites
Revised phylogeny of mouflon based on expanded sampling of mitogenomes
No full textMouflons are flagship species of the Mediterranean islands where they persist. Once thought to be the remnants of a European wild sheep population, archaeology suggests they were introduced by humans to the islands of Cyprus in the Early Neolithic (similar to 10,000 years ago) and later to Corsica and Sardinia. Their status as truly wild animals remains a subject of debate. To investigate the phylogenetic relationship between these island populations and other domestic and wild sheep from the Mediterranean region, we sequenced 50 mitogenomes of mouflons from Sardinia and Corsica, and modern and ancient Sardinian domestic sheep. A total of 68 additional publicly available mitogenomes were included in the comparative analysis and used to reconstruct the phylogeny of sheep and its closest wild relative, the mouflon (Ovis gmelini). Our study analyzed the evolutionary relationships within the C-E-X and haplogroup B clusters, showing that: a) Cyprus mouflons are more related to Anatolian and Iranian mouflons belonging to the wild haplogroup X, which seems to be basal to the domestic C and E haplogroups; b) Corsican and Sardinian mouflon arise from basal lineages associated with the early European expansion of domestic sheep. These results highlight the phylogenetic distinctiveness of the mouflon populations from the Mediterranean islands, suggesting a revision of their systematic classification and an update of the nomenclature for Sardinian and Corsican mouflons from the current status of subspecies of domestic sheep (Ovis aries musimon) to subspecies of their wild relatives (Ovis gmelini musimon) which would facilitate conservation efforts
Det svarta ödet i kvinnors liv : En kritisk diskursanalys av föreställningar om klimakteriet och kvinnors kroppar i en medicinsk kontext
No full textNear-collector electroprinting of cellulose acetate structures with large specific surface per volume
No full textThis study focuses on the fabrication and analysis of 3D-printed high-detail resolution cellulose acetate (CA) structures, particularly examining their specific surface area per volume (Sv). While electrospinning is a widely used technique for creating nanofiber membranes with high Sv, which is advantageous for applications like chromatography, the performance could be further improved by precisely controlling fiber placement. To further develop membranes, this research explores the use of electroprinting with small distances between nozzle and collector, here named near-collector electroprinting, to create 3D structures. By optimizing printing parameters, in particular the reduction of the nozzle-to-collector distance, 3D structures with precise fiber placement within a few micrometers were fabricated. The specific surface area per volume was calculated for both 3D-printed and electrospun filters. Results showed that 3D-printed structures with a 5 μm pitch achieved a Sv similar to electrospun filters. Incorporating polyethyleneimine (PEI) in the CA ink enabled the 3D-printed structures to gain ion binding capacity which was further investigated. This ion-exchange ability which integrated into the printing step, eliminating the need for a separate post-modification process in bio-separation applications. By switching the substrate voltage from positive to negative, relative to the grounded nozzle, the printed fiber diameter decreased substantially for the CA ink with PEI. The Sv for near-collector electroprinted fibers of this material could therefore potentially be higher than that of electrospun membranes, provided that an order of magnitude higher printing speed, than presently possible can be used. These findings suggest that near-collector electroprinted CA structures offer potential improvements in membrane design and performance, making them a promising alternative to traditional electrospun membranes for bio-separation applications
Liberal Legitimacy and Future Citizens
No full textIf the legitimate exercise of political power requires justifiability to all citizens, as John Rawls’s influential Liberal Principle of Legitimacy states, then what should we say about the legitimacy of institutions and actions that have a significant impact on the interests of future citizens? Surprisingly, this question has been neglected in the literature. This paper questions the assumption that it is only justifiability to presently existing citizens that matters, and provides reasons for thinking that legitimacy requires justifiability to future citizens as well. Further, it is argued that the presently dominant interpretation of Rawls’s principle is unable to take future citizens into account in an adequate way. Therefore, the inclusion of these citizens among those to whom justifiability is owed gives us good reasons to reject this interpretation, and to adopt a different understanding of the view