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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

This thesis investigates the implementation and experimental evaluation of velocity controllers for force and motion control. It also explores how adaptive estimators and velocity control can be integrated cooperatively to improve the accuracy and efficiency of such control systems. Additionally, the thesis addresses how uncertainties affect position tracking performance, offering insights and sol

The electrical energy landscape is changing rapidly with increasing electrification and renewable energy expansion. Smart meters deployed in households create opportunities for understanding energy consumption patterns through load disaggregation, the task of identifying individual appliances directly from aggregate electrical power data. Load disaggregation could be used for better understanding

This thesis investigates the performance of two model predictive control (MPC) variants for autonomous racing, using a 1:10-scale vehicle as a testbed for reference path-tracking experiments. The platform is equipped with a single inertial navigation system (INS) sensor, providing highly accurate odometry measurements. The controllers under study are the standard gradient-based MPC and a sampling-

This thesis investigates sensorless methods for detecting collisions and added weight in dual motor-driven industrial doors, to enhance safety without additional hardware. The study is grounded in the safety requirements outlined in EN 12453:2017 and conducted in collaboration with ASSA ABLOY. By monitoring deviations in the torque-producing current (IQ) from the motors, the developed methods iden

This master thesis presents the development of a vision-based feedback control system for automating sample placement in a virtual neutron beam emulated using a laser. The thesis was carried out on behalf of the European Spallation Source (ESS) to investigate the feasibility, possibilities and limitations of using a robotic automation system for sample alignment. Due to the radioactive research en

Infective endocarditis (IE) is a severe disease affecting the inner lining of the heart. Its diverse symptoms complicate diagnosis and the current main diagnostic tool is the Duke criteria which classifies suspected cases as definite, possible or rejected IE. A substantial portion of cases falls into the ambiguous “possible” category and there is a need for a more precise diagnostic system. This t

This thesis investigates how high-level planning principles can be deterministically and algorithmically incorporated into a sampling-based motion planner by modifying the structure of the RRT* algorithm. In particular, the requirement to always end a planned route by a reversing maneuver can be directly imposed through the expansion and connection logic of bidirectional search-trees, rather than

Small populations are prone to inbreeding depression due to the increased likelihood of mating between close relatives, resulting in the expression of deleterious recessive mutations. While this increases the risk of population extinction, high levels of inbreeding can initiate a purging process, where natural selection gradually eliminates strongly deleterious mutations. This purging effect has b