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Gait Biomechanics While Walking Down an Incline After Exhaustion

This gait biomechanics study investigated stride length (SL), stride duration (SDN), the peak values of ground reaction forces (GRFspeak), required coefficient of friction (RCOFpeak), leg joints’ angles (anglepeak), angular velocity (angvelx.peak), angular acceleration (angaccx.peak), minimum angle (anglemin.) of the foot, and muscles’ electromyography (EMG) during the stance phase (SP) of the dom

Consumers’ willingness to disclose their personal data in e-commerce: A reciprocity-based social exchange perspective

While personal data is invaluable to firms, the drivers of e-commerce customers' willingness to disclose their personal data remain tenuous. Using social exchange theory, we develop a model that explores the impact of consumers' perceived benefit, and relative power, on store trust, in turn driving their willingness to disclose their personal data. We collected our empirical data using a represent

Prevalence and functional impact of parkinsonian signs in older adults from the Good Aging in Skåne study : Parkinsonian signs in older adults

IntroductionMild parkinsonian signs (MPS) have been characterized by several definitions, using the motor part of the Unified Parkinson's Disease Rating Scale (UPDRS). We aimed to investigate the prevalence of MPS and their association with functional level and comorbidities in the oldest old.MethodCommunity-dwelling older adults (n = 559, median age 85, range 80–102 years) were examined regarding

Assessing structure and function of myelin in cervical spondylotic myelopathy: Evidence of demyelination

Purpose: To assess the extent of demyelination in cervical spondylotic myelopathy (CSM) using myelin water imaging (MWI) and electrophysiologic techniques.Methods: Somatosensory evoked potentials (SSEPs) and MWI were acquired in 14 patients with CSM and 18 age-matched healthy controls. MWI was performed on a 3.0T whole body magnetic resonance scanner. Myelin water fraction (MWF) was extracted for

Rapid myelin water imaging in human cervical spinal cord : Myelin Water Imaging in the Cervical Spinal Cord

PurposeMyelin water imaging (MWI) using multi-echo T2 relaxation is a quantitative MRI technique that can be used as an in vivo biomarker for myelin in the central nervous system. MWI using a multi-echo spin echo sequence currently takes more than 20 min to acquire eight axial slices (5 mm thickness) in the cervical spinal cord, making spinal cord MWI impractical for implementation in clinical stu

Next-generation phylogeography of the banded newts (Ommatotriton) : A phylogenetic hypothesis for three ancient species with geographically restricted interspecific gene flow and deep intraspecific genetic structure

Technological developments now make it possible to employ many markers for many individuals in a phylogeographic setting, even for taxa with large and complex genomes such as salamanders. The banded newt (genus Ommatotriton) from the Near East has been proposed to contain three species (O. nesterovi, O. ophryticus and O. vittatus) with unclear phylogenetic relationships, apparently limited intersp

Two transects reveal remarkable variation in gene flow on opposite ends of a European toad hybrid zone

Speciation entails a reduction in gene flow between lineages. The rates at which genomic regions become isolated varies across space and time. Barrier markers are linked to putative genes involved in (processes of) reproductive isolation, and, when observed over two transects, indicate species-wide processes. In contrast, transect-specific putative barrier markers suggest local processes. We studi

Genetic traces of hybrid zone movement across a fragmented habitat

Theoretical and empirical studies suggest that the structure and position of hybrid zones can change over time. Evidence for moving hybrid zones has been directly inferred by repeated sampling over time, or indirectly through the detection of genetic footprints left by the receding species and the resulting asymmetric patterns of introgression across markers. We here investigate a hybrid zone form

Inter-Vendor Reproducibility of Myelin Water Imaging Using a 3D Gradient and Spin Echo Sequence

Myelin water imaging can be achieved using multicomponent T2 relaxation analysis to quantify in vivo measurement of myelin content, termed the myelin water fraction (MWF). Therefore, myelin water imaging can be a valuable tool to better understand the underlying white matter pathology in demyelinating diseases, such as multiple sclerosis. To apply myelin water imaging in multisite studies and clin

Quantitative neuroimaging measures of myelin in the healthy brain and in multiple sclerosis

Quantitative magnetic resonance imaging (MRI) techniques have been developed as imaging biomarkers, aiming to improve the specificity of MRI to underlying pathology compared to conventional weighted MRI. For assessing the integrity of white matter (WM), myelin, in particular, several techniques have been proposed and investigated individually. However, comparisons between these methods are lacking

Myelin Water Atlas: A Template for Myelin Distribution in the Brain

BACKGROUND AND PURPOSEMyelin water imaging (MWI) is a magnetic resonance imaging technique that quantifies myelin in-vivo. Although MWI has been extensively applied to study myelin-related diseases in groups, clinical use in individual patients is challenging mainly due to population heterogeneity. The purpose of this study was twofold: (1) create a normative brain myelin water atlas depicting the

Myelin Water Fraction and Intra/Extracellular Water Geometric Mean T2 Normative Atlases for the Cervical Spinal Cord from 3T MRI

BACKGROUND AND PURPOSEAcquiring and interpreting quantitative myelin-specific MRI data at an individual level is challenging because of technical difficulties and natural myelin variation in the population. To overcome these challenges, we used multiecho T2 myelin water imaging (MWI) to create T2 metric healthy population atlases that depict the mean and variation of myelin water fraction (MWF), a

Increased incidence and improved survival in endometrial cancer in Sweden 1960-2014 : a population-based registry survey

BACKGROUND: An investigation of trends of incidence and net survival (NS) for endometrial cancer in Sweden.METHODS: Morphologically verified endometrial carcinoma diagnosed 1960 to 2014 were collected from the nation-wide Swedish Cancer Registry. Endometrial cancer patients were assessed with regards to time trends for incidence and 54,825 cases remained for survival analyses. Cases diagnosed 1995

Rapid myelin water imaging for the assessment of cervical spinal cord myelin damage

BackgroundRapid myelin water imaging (MWI) using a combined gradient and spin echo (GRASE) sequence can produce myelin specific metrics for the human brain. Spinal cord MWI could be similarly useful, but technical challenges have hindered routine application. GRASE rapid MWI was recently successfully implemented for imaging of healthy cervical spinal cord and may complement other advanced imaging

Silent T1 mapping using the variable flip angle method with B1 correction

PurposeTo compare the silent rotating ultrafast imaging sequence (RUFIS) to a traditional Cartesian spoiled gradient-echo (SPGR) acquisition scheme for variable flip angle (VFA) urn:x-wiley:07403194:media:mrm28178:mrm28178-math-0005 mapping.MethodsA two-point VFA measurement was performed using RUFIS and Cartesian SPGR in a quantitative phantom and healthy volunteers. To correct for urn:x-wiley:07

The Evaluation of Optic Nerves Using 7 Tesla “Silent” Zero Echo Time Imaging in Patients with Leber’s Hereditary Optic Neuropathy with or without Idebenone Treatment

Magnetic Resonance Imaging (MRI) of the Optic Nerve is difficult due to the fine extended nature of the structure, strong local magnetic field distortions induced by anatomy, and large motion artefacts associated with eye movement. To address these problems we used a Zero Echo Time (ZTE) MRI sequence with an Adiabatic SPectral Inversion Recovery (ASPIR) fat suppression pulse which also imbues the

Comparison of multi echo T2 relaxation and steady state approaches for myelin imaging in the central nervous system

The traditional approach for measuring myelin-associated water with quantitative magnetic resonance imaging (MRI) uses multi-echo T2 relaxation data to calculate the myelin water fraction (MWF). A fundamentally different approach, abbreviated “mcDESPOT”, uses a more efficient steady-state acquisition to generate an equivalent metric (fM). Although previous studies have demonstrated inherent instab