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A generic model for MIMO wireless propagation channels

We study the MIMO wireless channel, and derive a generic channel model that we believe has the ability to explain all important effects, including (i) interdependency of directions-of-arrival and directions-of-departure, (ii) large delay and angle dispersion by propagation via far clusters, (iii) rank reduction of the transfer function matrix. We point out the relevant propagation effects, and pro

Stochastic Analysis and Control of Real-Time Systems with Random Time Delays

The paper discusses modeling and analysis of real-time systems subject to random time delays in the communication network. A new method for analysis of different control schemes is presented. The method is used to evaluate different suggested schemes from the literature. A new scheme, using so called timestamps, for handling the random time delays is then developed and successfully compared with p

The impact of natural disaster on pediatric surgical delivery: a review of Haiti six months before and after the 2010 earthquake.

Little is known about pediatric surgical disease in resource-poor countries. This study documents the surgical care of children in central Haiti and demonstrates the influence of the 2010 earthquake on pediatric surgical delivery. METHODS: We conducted a retrospective review of operations performed at Partners in Health/Zanmi Lasante hospitals in central Haiti. RESULTS: Of 2,057 operations perfor

Pose Estimation with Radial Distortion and Unknown Focal Length

This paper presents a solution to the problem of pose estimation in the presence of heavy radial distortion and a potentially large number of outliers. The main contribution is an algorithm that solves for radial distortion, focal length and camera pose using a minimal set of four point correspondences between 3D world points and image points. We use a RANSAC loop to find a set of inliers and an i

Methodological reflections on gesture analysis in SLA and bilingualism research

Gestures, i.e. the symbolic movements that speakers perform while they speak, form a closely interconnected system with speech, where gestures serve both addressee-directed (‘communicative’) and speaker-directed (‘internal’) functions. This article aims (1) to show that a combined analysis of gesture and speech offers new ways to address theoretical issues in second language acquisition (SLA) and

Special Issue: ‘Contemporary Scandinavian Art Cinema and Screen Cultures in Transition’

The editorial outlines our main reasons for bringing scholarly attention to thetheme of Scandinavian art cinema and screen cultures in transition at this moment.It provides brief summaries of the issue’s five feature articles and presents somesuggestions for further research on the topic. We stress the importance of takinggender into account in future studies and call for a closer dialogue and mor

Cancer-associated fibroblasts rewire the estrogen receptor response in luminal breast cancer, enabling estrogen independence

Advanced breast cancers represent a major therapeutic challenge due to their refractoriness to treatment. Cancer-associated fibroblasts (CAFs) are the most abundant constituents of the tumor microenvironment and have been linked to most hallmarks of cancer. However, the influence of CAFs on therapeutic outcome remains largely unchartered. Here, we reveal that spatial coincidence of abundant CAF in

Automated Hippocampal Subfield Segmentation at 7T MRI

BACKGROUND AND PURPOSE: High resolution 7T MRI is increasingly used to investigate hippocampal subfields in vivo, but most studies rely on manual segmentation which is labor intensive. We aimed to evaluate an automated technique to segment hippocampal subfields and the entorhinal cortex at 7T MRI.MATERIALS AND METHODS: The cornu ammonis (CA)1, CA2, CA3, dentate gyrus, subiculum, and entorhinal cor

In vivo measures of tau burden are associated with atrophy in early Braak stage medial temporal lobe regions in amyloid-negative individuals

INTRODUCTION: It is unclear the degree to which tau pathology in the medial temporal lobe (MTL) measured by 18F-flortaucipir positron emission tomography relates to MTL subregional atrophy and whether this relationship differs between amyloid-β-positive and amyloid-β-negative individuals.METHODS: We analyzed correlation of MTL 18F-flortaucipir uptake with MTL subregional atrophy measured with high

Automated segmentation of medial temporal lobe subregions on in vivo T1-weighted MRI in early stages of Alzheimer's disease

Medial temporal lobe (MTL) substructures are the earliest regions affected by neurofibrillary tangle pathology-and thus are promising biomarkers for Alzheimer's disease (AD). However, automatic segmentation of the MTL using only T1-weighted (T1w) magnetic resonance imaging (MRI) is challenging due to the large anatomical variability of the MTL cortex and the confound of the dura mater, which is co

Structural and functional asymmetry of medial temporal subregions in unilateral temporal lobe epilepsy : A 7T MRI study

Mesial temporal lobe epilepsy (TLE) is a common neurological disorder affecting the hippocampus and surrounding medial temporal lobe (MTL). Although prior studies have analyzed whole-brain network distortions in TLE patients, the functional network architecture of the MTL at the subregion level has not been examined. In this study, we utilized high-resolution 7T T2-weighted magnetic resonance imag

Characterizing the human hippocampus in aging and Alzheimer's disease using a computational atlas derived from ex vivo MRI and histology

Although the hippocampus is one of the most studied structures in the human brain, limited quantitative data exist on its 3D organization, anatomical variability, and effects of disease on its subregions. Histological studies provide restricted reference information due to their 2D nature. In this paper, high-resolution (∼200 × 200 × 200 μm3) ex vivo MRI scans of 31 human hippocampal specimens are