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Purpose: To determine how image quality linked to tumor detection is affected by reducing the absorbed dose to 50% and 30% of standard dose levels, i.e. an average glandular dose of 1.26 mGy for a standard breast according to European guidelines. Material and methods: Tumors were computer simulated and inserted into 40 out of 90 normal, unprocessed images acquired from the screening department at

Effects of quantum fluctuations, like wobbling and γ-fluctuations, are examined in even- as well as in odd-particle systems by making use of a simple model based on the Bohr hamiltonian. The strong signature dependence observed in ΔI = 1 E2 transitions in odd nuclei is studied in the context of an axially asymmetric deformation. We point out the importance of the quantum fluctuations especially at

In this thesis, the consequences of introducing Yang-Mills fields into cosmology are investigated. This is done by the effective action approach, in which the coupling constant is allowed to depend on the quantum fields. The equation of state and scale factor are then found for the flat universe filled with either chromoelectric or chromomagnetic fields. From this, we draw conclusions about the hi

https://www.nano.lu.se/sites/nano.lu.se/files/cv_linke_january_2020.pdf - 2026-07-24

We have studied the geometry and electronic structure of the P-cluster in nitrogenase in four oxidation states: PN, P1+, P2+, and P3+. We have employed combined quantum mechanical and molecular mechanical (QM/MM) calculations, using two different density-functional theory methods, TPSS and B3LYP. The calculations confirm that the side chain of Ser-188 is most likely deprotonated in the partly oxid

We report fabrication and characterization of InAs nanowire devices with two closely placed parallel nanowires. The fabrication process we develop includes selective deposition of the nanowires with micron scale alignment onto predefined finger bottom gates using a polymer transfer technique. By tuning the double nanowire with the finger bottom gates, we observed the formation of parallel double q

Quantum phases can be classified by topological invariants, which take on discrete values capturing global information about the quantum state1–13. Over the past decades, these invariants have come to play a central role in describing matter, providing the foundation for understanding superfluids5, magnets6,7, the quantum Hall effect3,8, topological insulators9,10, Weyl semimetals11–13 and other p

Systemic lupus erythematosus (SLE) is a connective tissue disease where inflammatory activity affects several organ systems. An increased risk of cardiovascular disease has been identified in these patients, even after correction for traditional risk factors. The aim of the present study was to evaluate arterial stiffness and central hemodynamics in women with SLE in comparison to controls. Arteri

When new building systems are developed, these are often lightweight constructions with a periodical set of stiffeners, developed for use in load-bearing structures and dwellings. One of the main drawbacks of this type of building systems is the sound insulation, where flanking transmission is an important issue. A prediction model for flanking transmission of lightweight building structures is th

We report on a theoretical study of the electronic structures of the [1 1 1]-oriented, freestanding, zincblende InAs and InP nanowires with hexagonal cross sections by means of an atomistic sp3s∗, spinorbit interaction included, nearest-neighbor, tight-binding method. The band structures and the band state wave functions of these nanowires are calculated and the symmetry properties of the bands an

The study of electron motion in semiconductor billiards has elucidated our understanding of quantum interference and quantum chaos. The central assumption is that ionized donors generate only minor perturbations to the electron trajectories, which are determined by scattering from billiard walls. We use magnetoconductance fluctuations as a probe of the quantum interference and show that these fluc

Dynamical diffraction effects in thin single crystals produce highly monochromatic parallel x-ray beams with a mutual separation of a few microns and a time delay of a few femtoseconds—the so-called echoes. This ultrafast diffraction effect is used at X-Ray Free Electron Lasers in self-seeding schemes to improve beam monochromaticity. Here, we present a coherent x-ray imaging measurement of echoes

Background: Extracorporeal shock wave lithotripsy (ESWL) of kidney stones is losing ground to more expensive and invasive endoscopic treatments. Objective: This proof-of-concept project was initiated to develop artificial intelligence (AI)-augmented ESWL and to investigate the potential for machine learning to improve the efficacy of ESWL. Design, setting, and participants: Two-dimensional ultraso