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We consider an uplink time–division duplex cell–free massive multiple–input multiple–output (MIMO) system in which many user equipments (UEs) are simultaneously served by many access points (APs) via simple matched filtering processing. The propagation channel is modeled via the Ricean distribution, which includes a dominant line–of–sight component on top of diffuse scattering. The Ricean K–factor

Spatial correlation across an antenna array is known to be detrimental to the terminal signal-to- interference-plus-noise-ratio (SINR) and system spectral efficiency. For a downlink multiuser multiple-input multiple-output system (MU-MIMO), we show that the widely used, yet overly simplified, correlation models which generate fixed correlation patterns for all terminals tend to underestimate the s

Background: Differentiation between glioblastoma and brain metastasis may be challenging in conventional contrast-enhanced MRI. Purpose: To investigate if perfusion-weighted MRI is able to differentiate glioblastoma from metastasis and, as a second aim was to see if it was possible in the latter group, to predict the primary site of neoplasm. Material and methods: Hundred and fourteen patients wit

Closed-form approximations of the expected per-terminal signal-to-interference-plus-noise-ratio (SINR) and ergodic sum spectral efficiency of a multiuser multiple-input multiple-output system are presented. Our analysis assumes spatially correlated Ricean fading channels with maximum-ratio combining on the uplink. Unlike previous studies, our model accounts for the presence of unequal correlation

Huntington disease (HD) is a paradigmatic autosomal-dominant adult-onset neurodegenerative disease. Since the identification of an abnormal expansion of a trinucleotide repeat tract in the huntingtin gene as the underlying genetic defect, a broad range of transgenic animal models of the disease has become available and these have helped to unravel the relevant molecular pathways in unprecedented d

At the catalytic site for the hydrolysis of cellulose the enzyme cellobiohydrolase Cel7A binds the enantiomers of the adrenergic beta-blocker propranolol with different selectivity. Methyl-to-hydroxymethyl group modifications of propranolol, which result in higher affinity and improved selectivity, were herein studied by 1H,1H and 1H,13C scalar spin–spin coupling constants as well as utilizing the

General analysis of expected per-terminal signalto-interference-plus-noise-ratio (SINR) and ergodic per-cell sum spectral efficiency for a multi-cellular system with coordinated regularized zero-forcing (RZF) precoding is presented.An application to two-tier small-cell networks is considered, assuming independent and identically distributed (i.i.d.) and semi-correlated Rayleigh fading channels, wi

Amyotrophic lateral sclerosis (ALS) is the major adult-onset motor neuron disease, and is clinically, pathologically, and genetically associated with frontotemporal dementia, the second cause of dementia in the elderly. Here, we review the evidence linking thermoregulation and ALS. Indeed, while ALS is not classically associated with defective thermoregulatory function, its progression severely af

Closed-form approximations to the expected perterminal signal-to-interference-plus-noise-ratio (SINR) and ergodic sum spectral efficiency of a large multiuser multiple-input multiple-output system are presented. Our analysis assumes correlated Ricean fading with maximum ratio combining on the uplink, where the base station (BS) is equipped with a uniform linear array (ULA) with physical size restr

The quest for fundamental scientific knowledge triggers technological advancement. This has been particularly true for attosecond science in recent years: we assisted in the development of many new approaches - both experimentally and theoretically - that will have a high impact, not only on atomic and molecular physics, but also on optical technology. This special issue collects several of these

An accurate approximation is developed for the distribution of the instantaneous per-terminal signal-to-noise-ratio (SNR) of a downlink multiuser multiple-input multiple-output system with zero-forcing (ZF) precoding. Our analysis assumes a Ricean fading environment, where we show that the SNR at a given terminal is well approximated by the gamma distribution and we derive its parameters. The anal

This thesis considers the analysis of current and future cellular communication systems. The main focus is on multiuser multiple-input multiple-output (MU-MIMO) antenna systems. The goal of this work is to characterize the achievable spectral efficiency of MU-MIMO systems, as well as to analyze the performance of practical, linear MU-MIMO transceiver structures in heterogeneous propagation environ

Timing of return to the breeding area presumably optimizes breeding output in migrants. How timing affects the other components of fitness — survival, has been comparatively little studied. Returning too early in spring is expected to be associated with high mortality in insectivorous migrants when weather conditions are still unsuitable. Yet, males in particular arrive early to get access to the

A general framework for the analysis of expected per-user signal-to-interference-plus-noise-ratio (SINR) of a multiuser multiple-input-multiple-output system is presented. Our analysis assumes spatially correlated Rayleigh fading channels with regularized zero-forcing precoding on the downlink. Unlike previous works, our analytical expressions are averaged over the eigenvalue densities of the comp

Members of the order Haemosporida are protist parasites that infect mammals, reptiles and birds. This group includes the causal agents of malaria, Plasmodium parasites, the genera Leucocytozoon and Fallisia, as well as the species rich genus Haemoproteus with its two subgenera Haemoproteus and Parahaemoproteus. Some species of Haemoproteus cause severe disease in avian hosts, and these parasites d

Analytical expressions to approximate the expected per-user signal-to-interference-plus-noise-ratio (SINR) and ergodic sum-rate of a multiuser multiple-input-multiple-output system are presented. Our analysis assumes uncorrelated Ricean fading channels with regularized zero-forcing precoding on the downlink. The derived expressions are averaged with respect to the previously unknown arbitrary eige

In this paper we demonstrate the rate gains achieved by two-tier heterogeneous cellular networks (HetNets) with varying degrees of coordination between macrocell and microcell base stations (BSs). We show that without the presence of coordination, network densification does not provide any gain in the sum rate and rapidly decreases the mean per-user signal-to-interference-plus-noise-ratio (SINR).

In this paper, we present two important contributions. The first is demonstration of the use of subliminal levels of pseudo-random noise to enhance channel estimation, and the second is a joint time and frequency domain algorithm for multichannel inversion. An adaptive system is presented where the acoustic channel is accurately estimated and utilized. In this implementation, maximum length sequen

Bumblebees are important pollinators for a wide range of crops and wild plants. Performance of their colonies depends on pollen and nectar as food resources, but flowering plants are scarce in modern agricultural landscapes. It is well-known that semi-natural habitats can enhance floral resources and bumblebee abundance, but the impact of different crop types and their heterogeneity at the landsca

Workplace involvement in rehabilitation for patients with musculoskeletal pain may improve work ability. Convergence Dialogue Meeting (CDM) is a model aimed at helping the patient, the care giver, and the employer to support work ability and return-to-work. Our aim was to study the effect on work ability when adding a workplace dialogue according to CDM in physiotherapy practice for patients with