5,009 research outputs found
Rapid Immunoassay for the Detection of Genital Herpes Infection
Objective: We evaluated a new affinity membrane strip test for the diagnosis of herpetic genital
infections. Test strip results, which are available by immunoassay in 30 min without the need for special equipment,
were compared with the results of viral culture
Interoperability in the OpenDreamKit Project: The Math-in-the-Middle Approach
OpenDreamKit --- "Open Digital Research Environment Toolkit for the
Advancement of Mathematics" --- is an H2020 EU Research Infrastructure project
that aims at supporting, over the period 2015--2019, the ecosystem of
open-source mathematical software systems. From that, OpenDreamKit will deliver
a flexible toolkit enabling research groups to set up Virtual Research
Environments, customised to meet the varied needs of research projects in pure
mathematics and applications.
An important step in the OpenDreamKit endeavor is to foster the
interoperability between a variety of systems, ranging from computer algebra
systems over mathematical databases to front-ends. This is the mission of the
integration work package (WP6). We report on experiments and future plans with
the \emph{Math-in-the-Middle} approach. This information architecture consists
in a central mathematical ontology that documents the domain and fixes a joint
vocabulary, combined with specifications of the functionalities of the various
systems. Interaction between systems can then be enriched by pivoting off this
information architecture.Comment: 15 pages, 7 figure
Fatal Herpetic Hepatitis in Pregnancy
Background: Disseminated herpetic infections during pregnancy have
been reported in the literature
Mutations of fake weighted projective spaces
We characterise mutations between fake weighted projective spaces, and give explicit formulas for how the weights and multiplicity change under mutation. In particular, we prove that multiplicity-preserving mutations between fake weighted projective spaces are mutations over edges of the corresponding simplices. As an application, we analyse the canonical and terminal fake weighted projective spaces of maximal degree
Superlinear Scaling for Innovation in Cities
Superlinear scaling in cities, which appears in sociological quantities such
as economic productivity and creative output relative to urban population size,
has been observed but not been given a satisfactory theoretical explanation.
Here we provide a network model for the superlinear relationship between
population size and innovation found in cities, with a reasonable range for the
exponent.Comment: 5 pages, 5 figures, 1 table, submitted to Phys. Rev. E; references
corrected; figures corrected, references and brief discussion adde
Influence of impurity spin dynamics on quantum transport in epitaxial graphene
Experimental evidence from both spin-valve and quantum transport measurements
points towards unexpectedly fast spin relaxation in graphene. We report
magnetotransport studies of epitaxial graphene on SiC in a vector magnetic
field showing that spin relaxation, detected using weak-localisation analysis,
is suppressed by an in-plane magnetic field, , and thereby
proving that it is caused at least in part by spinful scatterers. A
non-monotonic dependence of effective decoherence rate on
reveals the intricate role of scatterers' spin dynamics in forming the
interference correction to conductivity, an effect that has gone unnoticed in
earlier weak localisation studie
Highly accurate retinotopic maps of the physiological blind spot in human visual cortex
The physiological blind spot is a naturally occurring scotoma corresponding with the optic disc in the retina of each eye. Even during monocular viewing, observers are usually oblivious to the scotoma, in part because the visual system extrapolates information from the surrounding area. Unfortunately, studying this visual field region with neuroimaging has proven difficult, as it occupies only a small part of retinotopic cortex. Here, we used functional magnetic resonance imaging and a novel data-driven method for mapping the retinotopic organization in and around the blind spot representation in V1. Our approach allowed for highly accurate reconstructions of the extent of an observer’s blind spot, and out-performed conventional model-based analyses. This method opens exciting opportunities to study the plasticity of receptive fields after visual field loss, and our data add to evidence suggesting that the neural circuitry responsible for impressions of perceptual completion across the physiological blind spot most likely involves regions of extrastriate cortex—beyond V1
Needle fenestration of popliteal artery covered stent graft to salvage inadvertent stent misdeployment
Endovascular methods have transformed treatment of lower extremity peripheral arterial disease but can still present technical challenges. We report the case of a 69-year-old man with rest pain who underwent superficial femoral artery recanalization with covered stents. During completion angiography, the distal stent was discovered to have been misdeployed into an anterior geniculate branch overlying the behind-the-knee popliteal artery. Subsequently, an endovascular reentry device was used to fenestrate the stent posteriorly to enter the lumen of the popliteal artery. Cutting balloons were used to enlarge the fenestration in the stent fabric, with placement of an additional 6 × 50-mm covered stent bridging from the popliteal artery into the fenestrated misdeployed covered stent. Completion angiography demonstrated no evidence of distal embolization and patent two-vessel runoff. The patient had an uncomplicated recovery and at 2 years of follow-up remained asymptomatic with documented popliteal stent patency
Automated characterization of noise distributions in diffusion MRI data
Knowledge of the noise distribution in diffusion MRI is the centerpiece to
quantify uncertainties arising from the acquisition process. Accurate
estimation beyond textbook distributions often requires information about the
acquisition process, which is usually not available. We introduce two new
automated methods using the moments and maximum likelihood equations of the
Gamma distribution to estimate all unknown parameters using only the magnitude
data. A rejection step is used to make the framework automatic and robust to
artifacts. Simulations were created for two diffusion weightings with parallel
imaging. Furthermore, MRI data of a water phantom with different combinations
of parallel imaging were acquired. Finally, experiments on freely available
datasets are used to assess reproducibility when limited information about the
acquisition protocol is available. Additionally, we demonstrated the
applicability of the proposed methods for a bias correction and denoising task
on an in vivo dataset. A generalized version of the bias correction framework
for non integer degrees of freedom is also introduced. The proposed framework
is compared with three other algorithms with datasets from three vendors,
employing different reconstruction methods. Simulations showed that assuming a
Rician distribution can lead to misestimation of the noise distribution in
parallel imaging. Results showed that signal leakage in multiband can also lead
to a misestimation of the noise distribution. Repeated acquisitions of in vivo
datasets show that the estimated parameters are stable and have lower
variability than compared methods. Results show that the proposed methods
reduce the appearance of noise at high b-value. The proposed algorithms herein
can estimate both parameters of the noise distribution automatically, are
robust to signal leakage artifacts and perform best when used on acquired noise
maps.Comment: v3: Peer reviewed version v2: Manuscript as submitted to Medical
image analysis v1: Manuscript as submitted to Magnetic resonance in medicin
Whole-Body Magnetic Resonance Imaging Assessment of the Contributions of Adipose and Nonadipose Tissues to Cardiovascular Remodeling in Adolescents
BACKGROUND:
Greater body mass index is associated with cardiovascular remodeling in adolescents. However, body mass index cannot differentiate between adipose and nonadipose tissues. We examined how visceral and subcutaneous adipose tissue are linked with markers of early cardiovascular remodeling, independently from nonadipose tissue.
METHODS AND RESULTS:
Whole‐body magnetic resonance imaging was done in 82 adolescents (39 overweight/obese; 36 female; median age, 16.3 [interquartile range, 14.4–18.1] years) to measure body composition and cardiovascular remodeling markers. Left ventricular diastolic function was assessed by echocardiography. Waist, waist:height ratio, and body mass index z scores were calculated. Residualized nonadipose tissue, subcutaneous adipose tissue, and visceral adipose tissue variables, uncorrelated with each other, were constructed using partial regression modeling to allow comparison of their individual contributions in a 3‐compartment body composition model. Cardiovascular variables mostly related to nonadipose rather than adipose tissue. Nonadipose tissue was correlated positively with left ventricular mass (r=0.81), end‐diastolic volume (r=0.70), stroke volume (r=0.64), left ventricular mass:end‐diastolic volume (r=0.37), and systolic blood pressure (r=0.35), and negatively with heart rate (r=−0.33) (all P<0.01). Subcutaneous adipose tissue was associated with worse left ventricular diastolic function (r=−0.42 to −0.48, P=0.0007–0.02) and higher heart rates (r=0.34, P=0.007) but linked with better systemic vascular resistance (r=−0.35, P=0.006). There were no significant relationships with visceral adipose tissue and no associations of any compartment with pulse wave velocity.
CONCLUSIONS:
Simple anthropometry does not reflect independent effects of nonadipose tissue and subcutaneous adipose tissue on the adolescent cardiovascular system. This could result in normal cardiovascular adaptations to growth being misinterpreted as pathological sequelae of excess adiposity in studies reliant on such measures
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