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Vitamin D intervention and bone : A randomized clinical trial in fair- and dark-skinned children at northern latitudes

Objectives: The aim of the study was to evaluate vitamin D status and effects of vitamin D intervention on bone mineral density (BMD) and content (BMC) in children with fair and dark skin in Sweden during winter. Methods: In a 2-center prospective double-blinded randomized intervention study 5- to 7-year-old children (n=206) with fair and dark skin in Sweden (55°N-63°N) received daily vitamin D su

Osteopontin protects against pneumococcal infection in a murine model of allergic airway inflammation

Background: In atopic asthma, chronic Th2-biased inflammation is associated with an increased risk of pneumococcal infection. The anionic phosphoglycoprotein osteopontin (OPN) is highly expressed in asthma and has been ascribed several roles during inflammation. This study aimed to investigate whether OPN affects inflammation and vulnerability to pneumococcal infection in atopic asthma. Methods: H

Microwave vs. Millimeter-Wave Propagation Channels: Key Differences and Impact on 5G Cellular Systems

Fifth generation cellular systems will be deployed in the microwave and millimeter–wave (mmWave) frequency bands (i.e., between 0.5–100 GHz). Propagation characteristics at these bands have a fundamental impact on each aspect of the cellular architecture, ranging from equipment design to real-time performance in the field. While we have a reasonable understanding of the propagation characteristics

Uplink Interference Analysis with RF Switching for Lens-Based Millimeter-Wave Systems

In this paper, we take a fundamental look at the interference characteristics of a lens-based millimeter-wave (mmWave) multiuser multiple-input multiple-output system (MU-MIMO) system. We consider a hybrid architecture, implemented via a bank of radio-frequency (RF) switches which perform beam selection followed by low-complexity uplink maximum-ratio combining (MRC) at baseband. Considering a Rotm

Revisiting MMSE Combining for Massive MIMO over Heterogeneous Propagation Channels

We consider a massive multiple-input multiple- output system with minimum-mean-squared-error processing on the uplink. A novel analytical framework is proposed to approximate the instantaneous signal-to-interference-plus-noise- ratio (SINR) of an arbitrary user terminal, as well as, the system sum spectral efficiency. Unlike previous studies, our methodology considers spatially correlated Ricean f

Simple modeling techniques for base-stock inventory systems with state dependent demand rates

In this paper new modeling techniques of (S- 1 , S) inventory systems (continuous review base-stock inventory systems) with state dependent demand rates are proposed. Examples of single-location (S- 1 , S) inventory systems where the demand, experienced by the system, varies due to the state of the system are, e.g., inventory models with partial backorders, inventory models with lost sales, invent

Large-scale and distributed optimization : An introduction

The recent explosion in size and complexity of datasets and the increased availability of computational resources has led us to what is sometimes called the big data era. In many big data fields, mathematical optimization has over the last decade emerged as a vital tool in extracting information from the data sets and creating predictors for unseen data. The large dimension of these data sets and

Biomarkers of Exposure to Pyrimethanil After Controlled Human Experiments

Pyrimethanil (PYM) is a fungicide used pre- and post-harvest on many crops. It has a low acute toxicity but is of toxicological concern because of its antiandrogenic properties. The aim of the current work was to investigate some metabolism and estimate elimination kinetics of PYM in humans after experimental oral and dermal exposure. A liquid chromatography triple quadrupole mass spectrometry (LC

Timing of maternal exposure to toxic cyanobacteria and offspring fitness in Daphnia magna : Implications for the evolution of anticipatory maternal effects

Organisms that regularly encounter stressful environments are expected to use cues to develop an appropriate phenotype. Water fleas (Daphnia spp.) are exposed to toxic cyanobacteria during seasonal algal blooms, which reduce growth and reproductive investment. Because generation time is typically shorter than the exposure to cyanobacteria, maternal effects provide information about the local condi

Effects of an MPL on water and thermal management in a PEMFC

In this study, the effects of adding a microporous layer (MPL) as well as the impact of its physical properties on polymer electrolyte fuel cell (PEMFC) performance with serpentine flow channels were investigated. In addition, numerical simulations were performed to reveal the effect of relative humidity and operating temperature. It is indicated that adding an extra between the gas diffusion laye

Impact of Harvest Date and Cutting Length of Grass Ley and Whole-Crop Cereals on Methane Yield and Economic Viability as Feedstock for Biogas Vehicle Fuel Production

Grass ley and whole-crop cereals used for biogas production are often finely chopped for subsequent ensiling and anaerobic digestion. Chopping can impact not only ensiling stability, digestibility and risk of process hick-ups in the digester but also harvesting capacity and fuel consumption. Based on field experiment data, the aim of this study was to investigate how three different nominal cuttin

Linking bacterial community composition to soil salinity along environmental gradients

Salinization is recognized as a threat to soil fertility worldwide. A challenge in understanding the effects of salinity on soil microbial communities is the fact that it can be difficult to disentangle the effects of salinity from those of other variables that may co-vary with salinity. Here we use a trait-based approach to identify direct effects of salinity on soil bacterial communities across

On the Performance of Cell-Free Massive MIMO in Ricean Fading

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 Variability in Multiuser Systems

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

Differentiation between glioblastomas and brain metastases and regarding their primary site of malignancy using dynamic susceptibility contrast MRI at 3T

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

Impact of Line-of-Sight and Unequal Spatial Correlation on Uplink MU-MIMO Systems

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