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Aims: Selective participation may hamper the validity of population-based cohort studies. The resulting bias can be alleviated by linking auxiliary register data to both the participants and the non-participants of the study, estimating propensity scores for participation and correcting for participation based on these. However, registry holders may not be allowed to disclose sensitive data on (in

Airborne Laser Scanning (ALS) is used to acquire three-dimensional (3D) city model data over large areas. However, because of the long ALS update cycle, building information models (BIM) could be utilized to maintain city models. In this study, we designed, implemented, and evaluated a methodology to formalize the integration of BIM data into city models. CityGML models were created from BIM data

Background: Presence of circulating tumor cells (CTCs) is a validated prognostic marker in metastatic breast cancer. Additional prognostic information may be obtained by morphologic characterization of CTCs. We explored whether apoptotic CTCs, CTC clusters and leukocytes attached to CTCs are associated with breast cancer subtype and prognosis at base-line (BL) and in follow-up (FU) blood samples i

In this paper, we study the trade-off between complexity and performance in massive MIMO systems with neural-network based digital pre-distortion (NN-DPD) blocks at the base station. In particular, we consider a multi-user massive MIMO system with per-antenna NN-DPDs, each with an adjustable NN architecture in terms of the size and the number of NN hidden layers. We first analyze the system perfor

The efficiency with which flying animals convert metabolic power to mechanical power dictates an individual's flight behaviour and energy requirements. Despite the significance of this parameter, we lack empirical data on conversion efficiency for most species as in vivo measurements are notoriously difficult to obtain. Furthermore, conversion efficiency is often assumed to be constant across flig

Background: Estimating excess mortality and years of life lost (YLL) attributed to coronavirus disease 19 (COVID-19) infection provides a comprehensive picture of the mortality burden on society. We aimed to estimate the impact of the COVID-19 pandemic on age- and sex-specific excess mortality and YLL in Sweden during the first 17 months of the pandemic. Methods: In this population-based observati

Background Additional to a child's genetic inheritance, environmental exposures are associated with schizophrenia. Many are broadly described as childhood adversity; modelling the combined impact of these is complex. We aimed to develop and validate a scale on childhood adversity, independent of genetic and other environmental liabilities, for use in schizophrenia risk analysis models, using data

Advanced cellular communication systems provide increased potential for opportunistic high-accuracy positioning. In this paper, long-term evolution (LTE) downlink signals from two commercial base stations (BS) are received by a massive antenna array mounted on a passenger vehicle. Multipath component (MPC) parameters, like delays and angle-of-arrival (AOA) are extracted from the received signals o

Three-dimensional city models are increasingly being used for analyses and simulations. To enable such applications, it is necessary to standardise semantically richer city models and, in some cases, to connect the models with external data sources. In this study, we describe the development of a new Swedish specification for 3D city models, denoted as 3CIM, which is a joint effort between the thr

A prerequisite for the design and evaluation of wireless systems is the understanding of propagation channels. While abundant propagation knowledge exists for bands below 6 GHz, the same is not true for millimeter-wave frequencies. In this paper, we present the design, implementation and measurement-based verification of a re-configurable 27.5-29.5 GHz channel sounder. Based on the switched array

An iterative algorithm is adopted to construct approximate representations of matrices describing the scattering properties of arbitrary objects. The method is based on the implicit evaluation of scattering responses from iteratively generated excitations. The method does not require explicit knowledge of any system matrices (e.g., stiffness or impedance matrices) and is well-suit

Background: Ovarian tumours are usually surgically removed because of the presumed risk of complications. Few large prospective studies on long-term follow-up of adnexal masses exist. We aimed to estimate the cumulative incidence of cyst complications and malignancy during the first 2 years of follow-up after adnexal masses have been classified as benign by use of ultrasonography. Methods: In the

With the present demand on fast and inexpensive aerosol source apportionment methods, the Aethalometer model was evaluated for a full seasonal cycle (June 2014–June 2015) at a rural atmospheric measurement station in southern Sweden by using radiocarbon and levoglucosan measurements. By utilizing differences in absorption of UV and IR, the Aethalometer model apportions carbon mass into wood burnin

Recension av Sam Popowich bok Confronting the Democratic Discourse of Librarianship

The paper present a parallel implementation of an image processing algorithm for the on-line, non-destructive quality assurance of the non-woven, fibrous web materials. The task of the algorithm is to compute the material microstructure descriptors. The premise underlying this work is that the microstructure determines the performance of the material and characterization of the microstructure may

Objective: To investigate the risk of stillbirth or neonatal death before 45 post-menstrual weeks in relation to gestational duration, stratified by body mass index (BMI) and parity. Design: Retrospective study. Setting: Data from the Swedish Medical Birth Register. Population: Singleton, cephalic births at between 39+0 and 42+2 weeks of gestation, 2005–2016 (n = 892 339). Methods: Relative risk r