Lund University Publications
Not a member yet
244244 research outputs found
Sort by
Luminescence chronology of the Velika Vrbica loess-palaeosol sequence (Wallachian Basin): Evaluating quartz and K-feldspar signals from MIS 5 to the Holocene
No full textThe Velika Vrbica loess-palaeosol sequence, situated on the south-western bank of the Danube River in northeastern Serbia, represents one of the key Quaternary records in the lower Danube basin, covering the MIS 5-MIS 1 period. Previous investigations of the upper 500 cm established a high-resolution chronology and revealed unexpected patterns of dust accumulation during interstadial phases. In this study, we extend the analysis to the full ∼12 m thickness of the sequence, spanning from Marine Isotope Stage (MIS) 5 to the Holocene, with emphasis on refining the geochronological framework and testing the performance of different luminescence signals. A comprehensive set of quartz optically stimulated luminescence (OSL) and K-feldspar post-infrared infrared stimulated luminescence (pIRIR290) ages, complemented by linear modulated OSL (LM-OSL) analyses, provides a robust chronology. Bayesian age-depth modelling constrains the timing of key stratigraphic units, including the S1 palaeosol (MIS 5), the overlying L1 loess (MIS 4–2) with its interstadial palaeosol (L1SS1), and the Holocene soil (S0). Quartz and K-feldspar ages display systematic differences: younger deposits show feldspar overestimation consistent with incomplete bleaching, whereas older horizons (MIS 5–4) yield excellent agreement between the two signals. LM-OSL results confirm that the fast component dominates most of the profile, supporting the reliability of equivalent dose determinations across multiple stratigraphic units. The resulting chronology demonstrates that the Velika Vrbica site preserves a continuous record of loess accumulation and pedogenesis over the last ∼130 ka. These findings not only refine the temporal framework for south-eastern European loess but also provide an important evaluation of the applicability and limitations of quartz and K-feldspar luminescence signals in establishing long-term chronologies
Uric acid and future complications in young individuals with type 1 diabetes : results from the Diabetes Incidence Study in Sweden (DISS) and the National Diabetes Registry of Sweden (NDR)
No full textAims/hypothesis: The aim of this work was to investigate whether baseline uric acid (UA) is associated with future complications among young individuals with newly diagnosed type 1 diabetes. Methods: UA levels were analysed in individuals, aged 15–34 years with newly diagnosed type 1 diabetes, from the nationwide Diabetes Incidence Study in Sweden (DISS) cohort to assess the relationship with macro- and microvascular complications later in life. Information on complications was obtained by record linkage to the National Diabetes Registry of Sweden and the National Patient Registry of Sweden. Individuals who developed complications during follow-up (n = 94) were matched for year and age at diagnosis (±2 years), sex and HbA1c with control individuals (n = 94) without complications. Results: Plasma UA levels at the time of diabetes diagnosis were significantly higher in individuals who later developed diabetes-related complications compared with those who did not, after a median follow-up of 19.0 years (IQR 16.3–21.0): 209.2 ± 68.9 vs 171.7 ± 50.2 µmol/l (p<0.001). The odds of developing complications were 1% higher for every 1 μmol/l rise in baseline UA, and individuals within the highest quartile of UA were more than three times more likely to develop diabetes-related complications later in life after adjusting for age, HbA1c, smoking and eGFR. Conclusions/interpretation: This study indicates that higher baseline UA levels at the time of type 1 diabetes diagnosis may be linked to both macrovascular and microvascular complications later in life
Surveillance of Lyme neuroborreliosis and Lyme borreliosis : estimates of disease burden in Southern Sweden 2009–2022
No full textBackground: Despite recommendations by EU, surveillance of Lyme neuroborreliosis (LNB) is still not fully implemented in all member states, Sweden being one of them. Laboratory-based notifications on positive Borrelia antibody index (AI) in paired cerebrospinal fluid-serum samples alone have been suggested for surveillance of LNB. Objectives: We aim to describe the epidemiology of Lyme borreliosis (LB) and LNB in Southern Sweden and assess if laboratory-based surveillance of LNB alone risks to underestimate the incidence in different populations. Methods: Using register data, we categorized cases from Region Skåne County during 2009–2022 into four groups: A) cases with positive Borrelia AI, and data on ICD-10 codes given to them; B) cases with ICD-10 code indicating LNB but without positive Borrelia AI; C) cases with Lyme arthritis; and D) other disease manifestations of LB, mainly erythema migrans. Results: Mean annual incidence for laboratory confirmed LNB (group A) was 3.2/100,000 inhabitants compared to 2.2/100,000 for cases with LNB diagnosis code but without positive Borrelia AI. Highest incidence in both these groups was noted among children 0–9 years old. Among cases in group B, 47% had a diagnosis code indicating facial nerve disorder, compared to19% in group A. For patients in group D, the mean annual incidence was 282/100,000 and increasing. Conclusion: A considerable number of patients received a LNB diagnosis code without laboratory confirmation. Children and those with facial nerve disorder as LNB manifestation are at risk to be underreported if surveillance of LNB is based on positive Borrelia AI alone
Beyond the Politics of Numbness
No full textAgainst the backdrop of Gaza and Europe’s muted response, this essay reflects on Elad Lapidot’s challenge to recognize the violence hidden in the language of peace
Transient AlH distribution around a burning micron-sized Al droplet quantified by laser absorption imaging
No full textThis study presents the first direct measurement of aluminum monohydride (AlH) distribution and dynamics during aluminum combustion. Single micron-sized aluminum droplets were burned in a controlled H₂O/N₂/O₂ environment to ensure repeatable conditions. A dual-wavelength laser absorption imaging system is used to quantify the AlH concentration with high temporal and spatial resolution. The results show that AlH concentration peaks near the droplet surface and decreases from about 1.2% to a negligible level within the condensation layer. As combustion proceeds, AlH extends outward from the droplet surface, and its distribution area stabilizes approximately 12 ms after ignition. This work demonstrates a robust technique for AlH quantification and provides novel data which is critical to understand the aluminum combustion mechanism
Fundamental and Applied Studies of Laser Plasma Accelerators
No full textConventional radio-frequency acceleration form the basis of most accelerators in industry today, and is a scaleable technology used in large-scale research laboratories all over the world. The final particle energy and the availability of the devices are, however, often limited by practical concerns such as price, size, and energy consumption. This prompts research into alternative acceleration mechanisms, among which laser wakefield acceleration has emerged as a demonstrated method for compact electron acceleration and X-ray production. Here, a short laser pulse is focused to high intensities (> 1018 W/cm2) in a gas, ionising the medium and displacing plasma electrons from the laser pulse. This forms an ion cavity trailing behind the laser pulse, which can accelerate electrons with gradients of hundreds of GV/m, three to four orders of magnitude higher than in conventional accelerators. While highly promising, significant work remains on understanding, controlling, and scaling the acceleration, all while preserving useful beam properties. This thesis is a stepping stone in this direction, compiling fundamental studies, development work, and research applications of laser wakefield acceleration. The sensitivity of the electron and X-ray pulses to pulse-front tilt in the driving laser pulse is assessed. The X-rays are applied to time-resolved liquid mass measurements of sprays from a gasoline direct injector. Using two independent gas jets for the laser wakefield accelerator, the plasma profile is tailored to focus and increase the energy of the electrons. This is also used to generate X-rays with reduced divergence. During the thesis work, a multi-terawatt titanium-sapphire laser system is replaced by an optical parametric amplification laser system, with shorter pulse durations. Using these few-cycle laser pulses, energy-bunched electron beams are produced. These give insight into the fundamental ionisation mechanisms used to inject electrons into the wakefield
Fossil capital at 10 : Andreas Malm on capitalism, energy, and resistance
No full textWith the publication of Fossil Capital in 2016, Andreas Malm reshaped how scholars understand the relationship between capitalism and fossil fuels. Energy humanities scholars Caleb Wellum and Imre Szeman interviewed Malm in November 2024 about the arguments and impact of Fossil Capital, the development of his thought in several subsequent books, and the shifting landscape of climate politics. At a time when the stakes of climate politics have never been higher, Malm's work is indispensable. This interview provides an opportunity to revisit Fossil Capital in light of the past decade's developments while also exploring the more radical propositions his recent work has put forth. From the role of sabotage in climate activism to the geopolitical entanglements of energy politics, Malm dissects the complex forces obstructing climate action and explores the strategies that might still be able to disrupt them, however powerful they might be. Readers will find in this conversation reflections on Malm's intellectual evolution and a considered engagement with the urgent question that has animated his work: how to bring about the end of fossil capitalism before it brings about the end of all of us
Energising the Polis? Analysing transition challenges to energy communities in Greece
No full textThe transition to a more decentralised energy system, by diversifying energy supply, and expanding renewable energy, is a declared EU objective as is evident from the Clean Energy for All Package. The EU has identified Energy Communities as one of the organisational forms that can facilitate this transition. Greece is a critical case within Europe. Research indicates that Energy Communities could help address energy poverty, drive decarbonisation of the energy sector, and contribute to rural development by tapping into the great potential for renewable energy generation in the country. Despite this high potential, Energy Communities are far less widespread in Greece than in many other EU countries. We investigate the policy challenges Energy Communities encounter in Greece. We base our analysis on policy scoping and interviews. We find challenges in all five domains of policy: Directionality, Demand Articulation, Experimentation, Policy Learning & Coordination and Justice. We find that the concept of Energy Communities is oftentimes co-opted by commercial players. Further, a lack of a coherent vision for Energy Communities in Greece and failing policy coordination inhibit a policy mix that can help a just rollout of the concept, leading to a situation where Energy Communities do not deliver the anticipated community benefits