Search results

The ultrafast energy transfer among the pigments of the B800-850 membrane antenna pigment-protein complex of the photosynthetic purple bacteria Rhodobacter sphaeroides and Rhodopseudomonas palustris LL has been studied with ≈ 100 fs tunable infrared pulses at room temperature and 77 K. It is shown that the B800→B850 transfer time is similar in both species and occurs with a characteristic time con

In this thesis, the inherent oxidation resistance of Al-Co-Cr-Fe-Ni based high entropy alloys have been remarkably enhanced by increasing the grain boundary area and recognizing the influence of the in situ Al2O3 nano-dispersoids. Isothermal continuous oxidation test based on thermogravimetric analysis (TGA) as well as extensive furnace oxidation, were conducted in the elevated temperature range o

Previous work has suggested that the βArg-10 residue forms part of the binding site for the B800 bacteriochlorophyll in the LH2 complex of Rhodobacter sphaeroides [Crielaard, W., Visschers, R. W., Fowler, G. J. S., van Grondelle, R., Hellingwerf, K. J., Hunter, C. N. (1994) Biochim. Biophys. Acta 1183, 473−482], and this is consistent with the X-ray crystallographic data that have been subsequent

Purpose: The purpose is to describe the Malmö Breast Tomosynthesis Screening Project from the beginning to where we are now, and thoughts for the future. Approach: In two acts, we describe the efforts made by our research group to improve breast cancer screening by introducing digital breast tomosynthesis (DBT), all the way from initial studies to a large prospective population-based screening tri

Background: FLASH radiotherapy using megavoltage (MV) photon beams should enable greater therapeutic efficacy, target deep seated tumors, and provide insights into mechanisms within FLASH. Purpose: In this study, we aim to show how to facilitate ultra-high dose rates (FLASH) with MV photons over a field size of 12–15 mm, using a 6 MeV (nominal) preclinical electron linear accelerator (linac). Our

Given the complex nature of agri-food value chains and related sustainability challenges, the question arises who has the agency and responsibility to address these challenges and facilitate systemic change. We address this question through a mixed method approach and examine experiences with agriculture among different actors along the agricultural value chains in Germany. Based on this, we explo

Natural autoantibodies (NAAbs) are immunoglobulins generated in the absence of antigen provocation, with no inherent pathogenic effect, but instead involved in maintaining immune homeostasis. We aimed to evaluate the implication of immunoglobulin G (IgG) antibodies against heat shock protein 90α (HSP90α) in systemic lupus erythematosus (SLE) patients, focusing on how those NAAbs may interfere with

This paper investigates the impact of artificial intelligence (AI) on hiring and employment, using the universe of job postings published by the Swedish Public Employment Service from 2014 to 2022 and full-population administrative data for Sweden. We exploit a detailed measure of AI exposure according to occupational content and find that establishments exposed to AI are more likely to hire AI wo

Operando resonant photoelectron spectroscopy (RPES) combined with modulated chemical excitation revealed the dynamic evolution of Ce3+/Ce4+ redox states at the surface of CeO2 during the CO oxidation reaction. Using alternating CO and O2 pulses as chemically modulated signals, we monitored the surface states in the valence band region, unveiling the evolution of electronic structure during the cat

In order to understand the origin of ultrafast carotenoid bandshifts upon photoexcitation of bacteriochlorophyll (BChl) molecules in antenna complexes of photosynthetic purple bacteria, we have performed sa-CASSCF(8,7)/6-31G (and 6-31G*) calculations for the low-lying excited states of the carotenoid rhodopin glucoside (RG). The LH2 environment was simulated via atomic point charges to represent t

In the pursuit of more sustainable agriculture, weeds play a dual role by threatening crop production and simultaneously contributing to farmland biodiversity. Management actions such as the use of fertilisers (fertilisation) may change weed abundance and community composition with consequences for both weed–crop competition and biodiversity. Alleviating the balance between yield and biodiversity

Transient absorption spectra and kinetics are used for detailed studies of energy transfer dynamics within the B850 ring of the LH2 antenna of the purple bacterium Rb. sphaeroides. The initial exciton relaxation was found to occur within the first 100 fs and no temperature dependence of this process was observed. Trnsient abcorption spectra of the LH2 antenna complex at 6 K revealed a new spectral

Background: Although up to 25% of proximal humeral fractures are isolated greater tuberosity fractures (IGTFs), comprehensive epidemiological data are lacking. Objectives: Describe the epidemiology and time trends of IGTF in Malmö, Sweden, 1944–2020. Methods: We identified IGTF in Malmö residents (≥18 years) by reviewing relevant radiology examinations during 17 sample years from 1944 to 2020. Fra

In 1825, an unnamed Stellenbosch official paused his tax collection duties to pen a poem in the margins of the opgaafrol. His verses capture the frustrations of colonial administration but the records themselves–annual tax censuses spanning 1685 to 1844–offer a far richer window into the Cape Colony’s social and economic history. First established by the Dutch East India Company and later maintain

Coherent nuclear oscillations in two intact photosynthetic light-harvesting pigments were observed for the first time using the approx. 40-fs tunable pulses from a mode-locked Ti:Sa laser. Furthermore, steady-state optical spectroscopy and theoretical calculations provide evidence that exciton states are present in the pigments. The possible antenna configurations that would give rise to the obser

Cameras are an ever growing part of all humans’ everyday life, from smartphones to surveillance cameras. One thing they all have in common is the need for a stable and focused image, even in conditions with camera movement as a result of external factors. To counteract the issue of blurry images from vibration disturbances, a technique called Optical Image Stabilization (OIS) is commonly used. In

Buildings are responsible for approximately 30% of global energy use, with HVAC systems accounting for 40% of that demand. Among these, data centers have become significant energy consumers, requiring highly efficient and stable cooling solutions. This project aims to explore data-driven control methods to improve the energy efficiency of data center cooling systems as well as reduce the effort an

Små klimatfickor – stor betydelse Bin, fjärilar och blomflugor är inte bara vackra att titta på – de gör också ett av naturens viktigaste jobb. Genom att flytta pollen mellan blommor ser de till att många växter kan föröka sig. Det gäller både vilda arter och en stor del av de grödor som vi människor äter. Utan dessa pollinatörer skulle vår biologiska mångfald minska kraftigt, och även vår livsmePollinators are essential for biodiversity and ecosystem services but face growing threats from climate change. Microclimates may buffer these impacts by providing localized climatic refugia. I assessed community-level and body size-dependent responses of bees, butterflies, and hoverflies to microclimatic temperature, humidity, wind, and structural shelter in semi-natural grasslands in southern Sw

Identifying resonance frequencies caused by liquid sloshing in modular transport systems is essential for effective vibration suppression and minimising mechanical wear. An example of such a system is the ACOPOStrak by B&R, which utilises a Zero Vibration Filter (ZVF) to mitigate these effects. Accurate tuning of this filter requires knowledge of the system’s resonance frequencies. Obtaining t