Sökresultat

The generation and characterization of ultrashort laser pulses in the deep ultraviolet spectral region is challenging, especially at high pulse repetition rates and low pulse energies. Here, we combine achromatic second harmonic generation and adaptive pulse compression for the efficient generation of sub-10 fs deep ultraviolet laser pulses at a laser repetition rate of 200 kHz. Furthermore, we si

Objective: To study how the choice of the first assisted reproductive technology treatment type affects the cumulative live birth rate (CLBR) in couples with high sperm DNA fragmentation index (DFI). Design: Longitudinal cohort study. Setting: University-affiliated fertility clinic. Patient(s): A total of 2,713 infertile couples who underwent assisted reproductive technology treatment between 2007

Small birds are hot creatures with an average body temperature of 40° Centigrade, and so must burn energy at a formidable rate to stay warm. This becomes quite the challenge in winter when birds are 40-50 degrees warmer than outside for extended periods, even in comparatively mild regions such as Scotland. Thus, the little bird in winter must spend most of the day either feeding or searching for f

Time-resolved photoemission electron microscopy (TR-PEEM) belongs to a class of experimental techniquescombining the spatial resolution of electron-based microscopy with the time resolution of ultrafast opticalspectroscopy. This combination provides insight into fundamental processes on the nanometer spatial andfemto/picosecond time scale, such as charge carrier transport in semiconductors or coll

The ignition of Quantum Cascade Lasers can occur from a state of oscillating field domains. Here, the interplay between lasing and the kinetics of traveling domain boundaries provides complex oscillation scenarios. We analyze our numerical findings in detail for a device operating at terahertz frequencies and manifest chaotic evolution by positive Lyapunov exponents. This shows that these importan

The existence of a miscibility gap limits the range of solid compositions which are possible to achieve under near-equilibrium growth conditions. Circumventing the miscibility gap is of paramount importance for device fabrication. We propose that one of the suppression mechanisms is the nucleus surface energy and explain how the surface energy influences the miscibility gap during nucleation from

The world of work is facing an ongoing pandemic and an economic downturn with severe effects worldwide. Workers trapped in precarious employment (PE), both formal and informal, are among those most affected by the COVID-19 pandemic. Here we call attention to at least 5 critical ways that the consequences of the crisis among workers in PE will be felt globally: (a) PE will increase, (b) workers in

Objectives: Risk of multiple sclerosis (MS) is low among first-generation immigrants in Sweden. We aimed to study incident MS in first- and second-generation immigrant groups. Materials & Methods: We included adults aged 18 years and older in Sweden in first-generation (n = 6 042 891) and second-generation (n = 4 860 469) sub-studies. MS was defined via two diagnoses in the Swedish National Pa

Type 3 diabetes (T3D) accurately reflects that dementia, e.g., Alzheimer’s disease, represents insulin resistance and neurodegeneration in the brain. Similar retinal microvascular changes were observed in Alzheimer’s and chronic stressed individuals. Hence, we aimed to show that chronic stress relates to T3D dementia signs and retinopathy, ultimately comprising a Stress syndrome prototype reflecti

Young birds in cold environments face a range of age-specific thermal challenges. Studying the thermal biology of young birds throughout ontogeny may further our understanding of how such challenges are met. We investigated how age and environmental parameters influenced surface temperature gradients across various body regions of wandering albatross (Diomedea exulans) chicks on Bird Island, South

Solid oxide cells are an exciting technology for energy conversion. Fuel cells, based on solid oxide technology, convert hydrogen or hydrogen-rich fuels into electrical energy, with potential applications in stationary power generation. Conversely, solid oxide electrolysers convert electricity into chemical energy, thereby offering the potential to store energy from transient resources, such as wi

The overall aim of this thesis work is to characterize artificial biomolecular motors, specifically the Lawnmower, a motor based on the burn bridges mechanism, and the Tumbleweed, a protein motor that employs ligand specific DNA-proteins binding to step along DNA. An overview of their operational principles is given, and initial results of our studies are presented, along with a review of currentl