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Background: The 2019 European Working Group on Sarcopenia in Older People (EWGSOP2) and the Sarcopenia Definitions and Outcomes Consortium (SDOC) have recently proposed sarcopenia definitions. However, comparisons of the performance of these approaches in terms of thresholds employed, concordance in individuals and prediction of important health-related outcomes such as death are limited. We addre

Den här uppsatsen handlar om stokastiska optimerings metoder. Inom områdena Artificiell intelligens och Maskininlärning är det vanligt att man vill skatta parametrar i en statistisk modell för att kunna göra prediktioner. Man använder sig då av en kostnadsfunktion som bestraffar prediktioner som ligger långt ifrån det riktiga värdet och minimerar denna med avseende på de statistiska parametrarna. This thesis is concerned with stochastic optimization methods. The pioneering work in the field is the article “A stochastic approximation algorithm” by Robbins and Monro [1], in which they proposed the stochastic gradient descent; a stochastic version of the classical gradient descent algorithm. Since then, many improvements and extensions of the theory have been published, as well as new version

Background: Hospital-acquired hyponatremia remains a feared event in patients receiving hypotonic fluid therapy. Our objectives were to assess post-operative plasma-sodium concentration and to provide a physiological explanation for plasma-sodium levels over time in children with acute appendicitis. Methods: Thirteen normonatremic (plasma-sodium ≥135 mmol/L) children (8 males), median age 12.3 (IQ

Researchers are increasingly recognizing that social movements are crucial for realizing deliberative democratic values. However, this raises two important questions: (1) what actions should count as deliberation and (2) whether we should demand more from activists than merely provoking or encouraging deliberation in a society. Building on current research on activists’ actual engagement with deli

We report on a study of the α-decay fine structure and the associated Eα-Eγ correlations in the decays of Os171,172 and Ir171,172,174. In total, 13 new α-decay energy lines have been resolved, and three new γ-ray transitions have been observed following the new decay branches to Re168 and W167. The weak α-decay branch from the bandhead of the νi13/2 band in Os171 observed in this work highlights a

Purpose: To present age- and sex-specific cumulative annual incidences of primary traumatic lateral patellar dislocation (LPD) and to detail patient characteristics and concomitant chondral injuries including osteochondral fractures, as visualized on magnetic resonance imaging (MRI), in a large consecutive cohort of knee-injured individuals. Methods: Data on primary traumatic lateral patellar disl

Drawing theoretic inspiration from the spatial turn within humanities, this article attempts to develop methods for studying placemaking in news media. This is done by a case study of the newspaper Þjóðviljinn, published in Ísafjörður, Iceland, in the late nineteenth century. The concept ‘banal placemaking’ is suggested for the kinds of spatial conceptions that occur in the paper without the expli

With this special issue and as part of the ELJ's endeavour to foster collaborative research projects on European integration, two of its board members, Jacob Öberg and Valsamis Mitsilegas, threw down a challenge to fellow expertsin European criminal law: to reflect on the normative foundations of European criminal law. This challenge first tookshape with an online symposium organised by Jacob with

Objective: Primary stenting of the superficial femoral artery (SFA) in intermittent claudication (IC) has been shown to increase health related quality of life (HRQoL) after 12 and 24 months. An extended follow up of HRQoL 36 and 60 months after randomisation is presented. Methods: A multicentre randomised controlled trial was conducted at seven vascular clinics in Sweden between 2010 and 2020. On

A high-order interior penalty method for scattering problems in two-dimensions is presented. Results for perfectly conducting objects illustrate the high accuracy of the method at low computational cost.

A meshless collocation method based on radial basis function (RBF) interpolation is presented for the numerical solution of Maxwell's equations. RBFs have attractive properties such as theoretical exponential convergence for increasingly dense node distributions. Although the primary interest resides in the time domain, an eigenvalue solver is used in this paper to investigate convergence properti

A high-order discontinuous Galerkin method for calculations of complex dispersion relations of two-dimensional photonic crystals is presented. The medium is characterized by a complex-valued permittivity and we relate for this absorptive system the spectral parameter to the time frequency. We transform the non-linear eigenvalue problem for a Lorentz material in air into a non-Hermitian linear eige

We study electromagnetic wave propagation in a periodic and frequency dependent material characterized by a space- and frequency-dependent complex-valued permittivity. The spectral parameter relates to the time-frequency, leading to spectral analysis of a holomorphic operator-valued function. We apply the Floquet transform and show for a fixed quasi-momentum that the resulting family of spectral p

For two-component composites, we address the inverse problem of estimating the structural parameters and decrease measurement errors in bulk property measurements. A measurement of the effective permittivity at one frequency gives microstructural information about the composite that is used in cross-property bounds to estimate the effective permittivity at other frequencies. We use this informatio

Meshless methods are a promising field of numerical methods recently introduced to computational electromagnetics. The potential of conformal and multi-scale modeling and the possibility of dynamic grid refinements are very attractive features that appear more naturally in meshless methods than in classical methods. The Radial Point Interpolation Method (RPIM) uses radial basis functions for the a

We study wave propagation in periodic and frequency dependent materials when the medium in a frequency interval is characterized by a real-valued permittivity. The spectral parameter relates to the quasi momentum, which leads to spectral analysis of a quadratic operator pencil where frequency is a parameter. We show that the underlying operator has a discrete spectrum, where the eigenvalues are sy

In this article we compute lossy Bloch waves in two-dimensional photonic crystals with dispersion and material loss. For given frequencies these waves are determined from non-linear eigenvalue problems in the wave vector. We applied two numerical methods to a demanding test case, a photonic crystal with embedded quantum dots that exhibits very strong and anamolous dispersion. The first method is b

A method is presented for estimating microstructural parameters from permittivity measurements of two-component composites. This structural information is described by a particular positive measure in the Stieltjes integral representation of the effective permittivity. The dependence on the geometrical structure can be reduced to the problem of calculating the moments of the measure. We present a

The bulk properties of composites are known to depend strongly on the microstructure. This dependence can be quantified in terms of a representation introduced by D. Bergman, which factorizes the geometry dependence from the contrast. Based on this analytic representation of the effective permittivity, we present a general scheme to estimate the microstructural parameters such as the volume fracti