Publikationer från Uppsala Universitet
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Systematic Study of Magnetic Molecule-Surface Junctions for Spin Transport Applications
No full textUnderstanding spin-dependent phenomena at the atomic scale is necessary for the development of future spintronic devices. The thesis aims to provide theoretical understanding of the interfaces consisting of single molecule magnet, bis(cyclopentadienyl)cobalt(II) (cobaltocene), and magnetic 2D materials: semiconducting CrI3, metallic Fe3GeTe2 and topological insulator MnBi2Te4. Furthermore, their potential application in spin-transport devices is assessed. The interfaces were found to be energetically stable and electronic structure showed hybridization of states across the interface, mainly near the Fermi level. Heisenberg exchange parameters were calculated using total energy and maximally localized Wannier functions approaches, showing large anisotropy in the molecule-substrate interaction. Additionally, probable exchange paths were analyzed both across the interface and within the substrates via hopping parameters extracted from Wannier hamiltonian. In the cobaltocene/CrI3 interface, calculations suggest the possibility of highly spin-polarized currents, which could be promising for spin-transport applications
HDV RNA Assays : Performance characteristics, clinical utility and challenges
No full textCoinfection with HBV and HDV results in hepatitis D, the most severe form of chronic viral hepatitis, frequently leading to liver decompensation and HCC. Pegylated interferon alpha, the only treatment option for chronic hepatitis D for many years, has limited efficacy. New treatments are in advanced clinical development, with one recent approval. Diagnosis and antiviral treatment response monitoring are based on detection and quantification of HDV RNA. However, the development of reliable HDV RNA assays is challenged by viral heterogeneity (at least 8 different genotypes and several subgenotypes), intrahost viral diversity, rapid viral evolution, and distinct secondary structure features of HDV RNA. Different RNA extraction methodologies, primer/probe design for nucleic acid tests, lack of automation, and overall dearth of standardization across testing laboratories contribute to substantial variability in performance characteristics of research-based and commercial HDV RNA assays. A World Health Organization (WHO) standard for HDV RNA, available for about 10 years, has been used by many laboratories to determine the limit of detection of their assays and facilitates comparisons of RNA levels across study centers. Here we review challenges for robust pan genotype HDV RNA quantification, discuss particular clinical needs and the importance of reliable HDV RNA quantification in the context of drug development and patient monitoring. We summarize distinct technical features and performance characteristics of available HDV RNA assays. Finally, we provide considerations for the use of HDV RNA assays in the context of drug development and patient monitoring
Swedish consuls in Galicia : the economic function of consuls in turbulent times (1793–1806)
No full textThis article is about the creation of a Swedish network of consuls in Galicia during the French Revolutionary and Napoleonic wars. Contrary to previous findings that show consuls with weak positions vis-Ã -vis the host authorities or the merchant community could do little to aid merchants and ships, the paper demonstrates that consuls could provide economic functions despite having no jurisdiction or official recognition from the receiving state. In contrast to those who view self-interest as something that hindered consuls from executing economic functions, the paper demonstrates a synergy between self-interest and public goods. The paper also shows a growth in Swedish trade with Galicia, but it is unclear if the network members facilitated this development. Lastly, the article argues that the creation of the Swedish consular service, contrary to previous research, cannot be seen as driven by the Swedish central authorities with a mercantilistic agenda in mind. Instead, the process was rather dynamic and involved various actors and agendas
Business ecosystems as a way to activate lock-in in business models : a theoretical integration
No full textAs technology-enabled innovations have become ever more common, successful firms have struggled to stay ahead of their imitators. One way for an innovating firm to defend itself from imitators is to activate lock-in mechanisms. These mechanisms discourage actors in the innovating firm’s business model from migrating to imitators. Current business model theory explains how to establish lock-in through loyalty, sunk costs, direct network effects, indirect network effects, and data network effects. This paper extends the current understanding of lock-in by integrating business ecosystem theory with business model theory. The objective is to outline how firms can strategically configure their business ecosystems to activate lock-in mechanisms that discourage actors (e.g., customers, suppliers, and partners) from migrating to competitors. When an innovating firm’s business model is deliberately configured to activate lock-in by establishing a business ecosystem, it can withstand imitation. Real-life examples are provided to illustrate this mechanism in action. The paper also provides managerial recommendations for how to activate lock-in by establishing a business ecosystem. Finally, it highlights topics that deserve further research
Performance-optimized diatom-SiOx anodes for Li-ion batteries by preserving the nanostructured SiO2 shells of diatom microalgae and tailoring oxygen content
No full textNanostructured silicon oxides (SiOx) are close-to-market anode materials for increasing the energy density of next-generation lithium-ion batteries (LIBs), offering a balance between high capacity and enhanced cycling stability. However, achieving precise control over SiOx composition while maintaining structural integrity remains a challenge. In this study, we pioneer the use of nanostructured diatom-SiO2 frustules from industrially cultured Nitzschia sp. microalgae as a sustainable and tunable precursor for high-performance SiOx anodes via scalable magnesiothermic reduction reaction (MgTR). By optimizing the Mg-to-diatom-SiO2 molar ratio, we demonstrate controlled partial reduction of SiO2, yielding Si nanocrystals embedded within an SiO2 matrix. Notably, we reveal that the preservation of diatom-SiOx nanoporosity is highly sensitive to reaction exothermic conditions and is effectively stabilized by introducing NaCl as a heat scavenger. Tailoring the reactant composition (SiO2:Mg:NaCl = 1:1:2.5) resulted in anodes with superior electrochemical performance, delivering high capacity retention over 200 cycles. Through a comprehensive suite of characterization techniques, we establish the structure-property-performance relationships governing SiOx anode behavior. These findings mark a major advancement in sustainable SiOx anode design, providing a scalable strategy for integrating biologically templated nanostructures into high-performance LIBs
ESG som värdeskapande faktor? : En studie av Stockholmsbörsen
No full textDenna studie undersöker sambandet mellan ESG-poäng (Environmental, Social och Governance) och riskjusterad avkastning för bolag noterade på Stockholmsbörsen under perioden 2016–2023. Forskning kring ESG och finansiell prestation har visat på varierande resultat, vilket motiverar ytterligare studier. Syftet är att undersöka hur ESG-poäng påverkar den riskjusterade avkastningen och om ESG kan betraktas som en självständig värdeskapande faktor när bolagsstorlek beaktas. Studien använder kalenderportföljmetoden och fyrap ortföljer har konstruerats baserade på börsvärde och ESG-poäng. Data om aktiekurser, börsvärde och ESG-poäng har hämtats från LSEG Eikon. Resultaten visar att portföljer med lägre ESG-poäng tenderar att generera högre riskjusterad avkastning. Hedgeportföljer som konstruerats för att isolera ESG-effekten, uppvisade negativa alfa-värden. Studien drar slutsatsen att ESG-poäng inte bör betraktas som en isolerad indikator för överavkastning på Stockholmsbörsen under den studerade perioden och att ESG-faktorer snarare bör integreras i en bredare investeringsanalys
Fishscapes : Exploring a long-term perspective of fisheries and aquatic habitat structures in the Baltic Sea region through interdisciplinary studies
No full textUnderstanding fishing practices through the zooarchaeological record offers crucial insights into past human-environment interactions, subsistence strategies, and the development of the modern fishery practices. Past fishing practices varied widely depending on geographical location, environmental factors, and cultural contexts. In this thesis, I explore fish and fisheries in the Baltic Sea from different time frames. Evidence from archaeological fishbones and teeth provides a direct link to fishing practices in the past. Species diversity and anatomical distribution patterns are used to explore fishing methods. Isotope analysis on fish teeth offers further refinement of ecological patterns, including fish migration and mobility. Using zooarchaeological materials from Gotland and Åland, this thesis identifies and discusses patterns in relation to climate change and cultural shifts from the Mesolithic until the Early Modern Period. By applying the theoretical framework of negative space and values the formation of past assemblages and the remains excavated in the present are evaluated. Using strontium isotope analysis, the likely origin, fresh or brackish water, of euryhaline fish on Gotland is explored. The results indicate that fluctuations in aquatic habitat utilisation are tied to environmental shifts and influenced by cultural preferences and values. To understand how fish are transformed from living creatures to products for human consumption, Medieval zooarchaeological material from Åland was used to investigate shifting patterns in the transportation of cod from a local fishery. A possible difference in fish products was identified related to the Gotlandic sources. This has implications on how the written record might be interpreted. The aspects above are discussed in a diachronic way and modern concepts such as fishing down the food web are used to examine the sustainability of past fisheries. The findings contribute to broader discussion on past aquatic resource utilisation and fish's value and identities at different time frames in the Baltic Sea context. Highlighting the significance of fishbone analyses and the potential to incorporate archaeological data in contemporary sustainability discourse.
Investigations of hypoglycemic events and the role of GABA in type 1 diabetes
No full textIntroduction: Hypoglycemia in type 1 diabetes (T1D) ranges from mild to life-threatening events, yet most studies of hypoglycemia frequency rely on self-reported or aggregated data. Residual endogenous insulin production is associated to fewer severe hypoglycemic events, highlighting the potential benefit of preserving or restoring insulin production. For this purpose, gamma-aminobutyric acid (GABA) has emerged from experimental studies as a potential therapeutic drug candidate. Aim: This thesis aimed to investigate the real-world frequency of hypoglycemia in children and adolescents with T1D, and to evaluate GABA’s therapeutic potential in a clinical trial. Methods: Five studies were included. Endogenous GABA, C-peptide, counter-regulatory hormones and cytokine levels were analyzed in plasma. A controlled-release oral formulation of GABA (Remygen®) was assessed in a randomized controlled Phase I/II clinical trial in individuals with long-standing T1D (n=35) for safety, effect on endogenous insulin production and hypoglycemic counter-regulation. The real-world frequency of hypoglycemia and its relationship to overall metabolic control and age was evaluated using retrospective continuous glucose monitoring (CGM)-data and clinical records. More than 50,000 hypoglycemic events were analyzed. Additionally, a single-metric scoring model for CGM-data evaluation was developed based on n=82,114 days of CGM-data by assessing three dimensions of glucose control. The models validity was evaluated against clinical treatment targets and interpretations of a clinical expert board (CEB). Results: GABA levels did not differ between individuals with T1D and healthy controls, but correlated with anti-GAD and cytokines. GABA treatment showed no improvements in endogenous insulin production or hypoglycemic counter-regulation, but side-effects were commonly observed. In the retrospective studies on CGM-data, mild hypoglycemic events (<3.9 mmol/L) were common. On average occurring on a near daily basis, regardless of age or metabolic control. However, no increased risk of severe- or serious (<3.0 mmol/L) hypoglycemia was observed in children achieving HbA1c ≤48 mmol/mol. The developed CGM scoring model correlated well with CGM-metrics and CEB interpretations. Conclusions: Despite technological advancements, hypoglycemia remains a persistent challenge in T1D. GABA failed to regain beta-cell function, underscoring the need for alternative therapies in this aspect. Meanwhile, models for enhanced CGM analyses may aid in optimizing glucose management
Differential cross-section measurements of Higgs boson production in the H → τ+τ− decay channel in pp collisions at √s = 13 TeV with the ATLAS detector
No full textDifferential measurements of Higgs boson production in the τ-lepton-pair decay channel are presented in the gluon fusion, vector-boson fusion (VBF), VH and t¯tH associated production modes, with particular focus on the VBF production mode. The data used to perform the measurements correspond to 140 fb−1 of proton-proton collisions collected by the ATLAS experiment at the LHC. Two methods are used to perform the measurements: the Simplified Template Cross-Section (STXS) approach and an Unfolded Fiducial Differential measurement considering only the VBF phase space. For the STXS measurement, events are categorized by their production mode and kinematic properties such as the Higgs boson’s transverse momentum (pHT), the number of jets produced in association with the Higgs boson, or the invariant mass of the two leading jets (mjj). For the VBF production mode, the ratio of the measured cross-section to the Standard Model prediction for mjj > 1.5 TeV and pHT > 200 GeV (pHT < 200 GeV) is 1.29+0.39−0.34 (0.12+0.34−0.33). This is the first VBF measurement for the higher-pHT criteria, and the most precise for the lower-pHT criteria. The fiducial cross-section measurements, which only consider the kinematic properties of the event, are performed as functions of variables characterizing the VBF topology, such as the signed ∆ϕjj between the two leading jets. The measurements have a precision of 30%–50% and agree well with the Standard Model predictions. These results are interpreted in the SMEFT framework, and place the strongest constraints to date on the CP-odd Wilson coefficient cH∼W.For complete list of authors see http://dx.doi.org/10.1007/JHEP03(2025)010</p
Win-Win More Sustainable Routes for Acetic Acid Synthesis
No full textCurrent efforts to decarbonize the chemical sector by using captured CO2 and electrolytic H2 typically lead to high production costs and environmental collateral damage. Hence, there is a clear need to look for alternative, more efficient synthesis routes that could pave the way for a fully sustainable chemical industry. Bearing this in mind, here, we evaluate the economic and environmental implications of two low technology readiness level (TRL) novel single-step synthesis routes for acetic acid production using CO2 as a raw material: gas-to-acid methane carboxylation and semiartificial photosynthesis. Using process simulation and life-cycle assessment, we determine that these pathways, under a specific set of assumptions, could outperform the business-as-usual methanol carbonylation process at their current development state in terms of global warming, human health, ecosystem quality, and resource scarcity impacts, showing no signs of burden shifting. Furthermore, these routes also result in lower production costs derived from the reduced energy requirement associated with a single synthesis step. Overall, our preliminary results of the low TRL technologies based on experimental data highlight the potential economic and environmental benefits of exploring alternative synthesis routes, which could help bridge the current fossil-based industrial landscape to a more sustainable future