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Background: More than 70 million magnetic resonance (MR) examinations are produced every year. Patients and personnel are exposed to electromagnetic fields at levels that exceed those normally found in our surroundings or in industry. Three types of electromagnetic field exposure must be considered in regard to MR safety: the strong force of the static magnetic field, the time-varying gradient mag
Accurate carrier-phase integer ambiguity resolu-tion is fundamental for high precision global navigation satellitesystems (GNSSs). In this paper we extend a recently proposedmixture Kalman filter solution to integer ambiguity resolution.We utilize the Fisher information matrix to project the acquiredmeasurements into a lower-dimensional subspace, formulatingan optimization program to find the proj
Unfair work distribution is common in project-based learning with teams of students. One contributing factor is that students are differently skilled developers. To mitigate the differences in a course with group work, we introduced mandatory programming lab sessions. The intervention did not affect the work distribution, showing that more is needed to balance the workload. Contrary to our goal, t
Estimating receiver and sender positions is often solved using a stratified, two-tiered approach. In the first step the problem is converted to a low-rank matrix estimation problem. The second step can be seen as an affine upgrade. This affine upgrade is the focus of this paper. In the paper new efficient algorithms for solving for the upgrade parameters using minimal data are presented. It is als
In this work, we present the misspecified Gaussian Cramér-Rao lower bound for the parameters of a harmonic signal, or pitch, when signal measurements are collected from an almost, but not quite, harmonic model. For the asymptotic case of large sample sizes, we present a closed-form expression for the bound corresponding to the pseduo-true fundamental frequency. Using simulation studies, it is show
Background: Sports-related concussion (SRC) is increasingly recognized as a potential health problem in ice hockey. Quality of life (QoL) in players retiring due to SRC has not been thoroughly addressed. Materials & methods: QoL using the Sports Concussion Assessment Tool 5th Edition, Impact of Event Scale-Revised and Short Form Health Survey was measured in Swedish ice hockey players who reti
Most parametric fundamental frequency estimators make the implicit assumption that any corrupting noise is additive, white Gaus-sian. Under this assumption, the maximum likelihood (ML) and the least squares estimators are the same, and statistically efficient. However, in the coloured noise case, the estimators differ, and the spectral shape of the corrupting noise should be taken into account. To
Abstract: The β-decay half-life and the delayed neutron emission of 60Ca are studied within a microscopic model, which is based on the Skyrme interaction T45 to construct single-particle and phonon spaces. We observe a redistribution of the Gamow–Teller strength due to the phonon-phonon coupling and the tensor correlations, considered in the model. For 60Sc, the spin-parity of the ground state is
Lithium abundances are presented for 91 dwarf and subgiant stars in the Galactic bulge. The analysis is based on line synthesis of the 7Li line at 6707 Å in high-resolution spectra obtained during gravitational microlensing events, when the brightnesses of the targets were highly magnified. Our main finding is that bulge stars at sub-solar metallicities that are older than about eight billion year
Purpose: To compare the effects of ageing and glaucoma progression on the thickness of the circumpapillary retinal nerve fibre layer (cpRNFL) and to evaluate the performance of a set of optical coherence tomography (OCT) progression analyses. Methods: The cpRNFL was measured twice by OCT at each of two visits made 10 years apart in 69 healthy individuals and 49 glaucoma patients. Both visits also
Purpose: The aim of this prospective study was to validate the diagnostic performance of computed tomography angiography (CTA) in endoprosthesis stenosis in the superior mesenteric artery (SMA) using mean arterial pressure (MAP) gradients during angiography as a reference method. Methods: Twenty-nine patients with mesenteric atherosclerotic disease underwent 45 paired measurements of endoprosthesi
INTRODUCTION: Numerous prior studies, even from countries with free access to care, have associated long travel time to care with poor survival in patients with colorectal cancer. METHODS: This is a data-linkage study of all 3718 patients with colorectal cancer, diagnosed between 2007 and 2013 in Northern Sweden, one of the most sparsely populated areas in Europe. Travel time to nearest hospital w
INTRODUCTION: Influenza may precipitate cardiovascular disease, but influenza typically peaks in winter, coinciding with other triggers of myocardial infarction (MI) such as low air temperature, high wind velocity, low atmospheric pressure, and short sunshine duration. OBJECTIVE: We aimed to determine the relationship of week-to-week variation in influenza cases and acute MI, controlling for meteo
Even though abdominal aortic aneurysm (AAA) and coronary heart disease (CHD) are both related to atherosclerosis, there could be important differences in risk factors. Based on Malmö Diet and Cancer Cohort, the incidence of AAA and CHD was followed prospectively. Cox regression was used to calculate the association of each factor with AAA and CHD and hazards ratio were compared using a modified Lu
Objective: To describe the demographics and clinical findings in patients with otorrhoea in Angola. Methods: A total of 411 patients with otorrhoea presenting in the ear, nose and throat clinic in Luanda and healthcare centres in other Angolan provinces underwent interview and clinical examination. We describe the demographics and clinical characteristics of the patients. Results: The majority (64
The evolution of orchids and bats is an example of DNA’s own evolution which has resulted in structures and functions which are not necessarily related to any obvious advantage to the organism. The flowers of orchids resemble: humans, apes, lizards, frogs and even shoes. The faces of bats resemble plant leaves but also horseshoes. These similarities are not accidental because they emerge repeatedl
