6,774 research outputs found
Anisotropy of TeV and PeV cosmic rays with IceCube and IceTop
The interaction of high energy cosmic rays with the Earth's atmosphere
produces extensive air showers of secondary particles with a large muon
component. By exploiting the sensitivity of neutrino telescopes to high energy
muons, it is possible to use these detectors for precision cosmic ray studies.
The high rate of cosmic-ray muon events provides a high-statistics data sample
that can be used to look for anisotropy in the arrival directions of the parent
particles at the per-mille level.
This paper reports on the observation of anisotropy in the cosmic ray data
collected with the IceCube neutrino telescope in the 20-400 TeV energy range at
multiple angular scales. New data from the IceTop air shower array, located on
the ice surface above IceCube, shows an anisotropy that is consistent with the
high-energy IceCube results. The sensitivity of IceTop to all the components of
the extensive air shower will allow us to explore in more detail the
characteristics of the primary cosmic rays associated with the observed
anisotropy.Comment: To appear in the Proceedings of the 2011 Very Large Volume Neutrino
Telescopes Conferenc
A partial differential equation for the strictly quasiconvex envelope
In a series of papers Barron, Goebel, and Jensen studied Partial Differential
Equations (PDE)s for quasiconvex (QC) functions \cite{barron2012functions,
barron2012quasiconvex,barron2013quasiconvex,barron2013uniqueness}. To overcome
the lack of uniqueness for the QC PDE, they introduced a regularization: a PDE
for \e-robust QC functions, which is well-posed. Building on this work, we
introduce a stronger regularization which is amenable to numerical
approximation. We build convergent finite difference approximations, comparing
the QC envelope and the two regularization. Solutions of this PDE are strictly
convex, and smoother than the robust-QC functions.Comment: 20 pages, 6 figures, 1 tabl
Differences in intention to use educational RSS feeds between Lebanese and British students: A multiāgroup analysis based on the technology acceptance model
Really Simple Syndication (RSS) offers a means for university students to receive timely updates from virtual learning environments. However, despite its utility, only 21% of home students surveyed at a university in Lebanon claim to have ever used the technology. To investigate whether national culture could be an influence on intention to use RSS, the survey was extended to British students in the UK. Using the Technology Adoption Model (TAM) as a research framework, 437 students responded to a questionnaire containing four constructs: behavioral intention to use; attitude towards benefit; perceived usefulness; and perceived ease of use. Principle components analysis and structural equation modelling were used to explore the psychometric qualities and utility of TAM in both contexts. The results show that adoption was significantly higher, but also modest, in the British context at 36%. Configural and metric invariance were fully supported, while scalar and factorial invariance were partially supported. Further analysis shows significant differences between perceived usefulness and perceived ease of use across the two contexts studied. Therefore, it is recommended that faculty demonstrate to students how educational RSS feeds can be used effectively to increase awareness and emphasize usefulness in both contexts
Screening for microscopic hematuria in school-age children of the Gorgan city
Screening for hematuria was carried out in 3000 school-age children (6 to14 years old) in Gorgan, Iran, using a fresh morning urine sample. At the initial step, 208 (6.8%) had positive dipstick tests for blood, which decreased to 35 (1.2%) at the second step. Of the 35 children with hematuria, 27 (77.1%) were girls and 8 (22.9%) were boys. Twenty-six children were further evaluated of whom 5 had normal findings, and 7 had hypercalciuria, 13 had nephrolithiasis, and in 1 had a large cystic lesion on ultrasonography, ultimately diagnosed as oncocystoma
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Use of creative tools, technologies, processes and practices in the sectors of Art, Media, and Architecture: State-of the-Art and desired future scenarios
The aim of the paper is to analyse and present the preliminary findings of the EU FP7 funded CRe-AM project for the Art, Media, and Architecture sectors. This project bridges communities of technology providers and innovators with the creative industries, with the aim to build sector-specific dynamic roadmaps for the future of the European creative industries by examining the current state-of-the-art tools, technologies, processes, and practices supporting the creative process against the future scenarios envisioned by stakeholders in these sectors.This work was carried out as part of CRe-AM project, which is supported by European Commission (grant agreement nĀ°612451)
Hematologic, hepatic, and renal function changes in hospitalized patients with Middle East respiratory syndrome coronavirus
Background
There are no longitudinal data on the changes in hematologic, hepatic, and renal function findings in patients with Middle East respiratory syndrome coronavirus (MERSāCoV) infection.
Methods
This is a retrospective cohort study of 16 MERSāCoV patients, to describe the hematological, hepatic, and renal findings of patients with MERSāCoV.
Results
During the 21 days of observation, there was no significant change in the hepatic panel or creatinine tests. There was a significant increase in the mean Ā± SD of the white blood cell count from 8.3 Ā± 4.6 to 14.53 Ā± 7 (P value = 0.001) and an increase in mean Ā± SD of the absolute neutrophil count from 6.33 Ā± 4.2 to 12 Ā± 5.5 (P value = 0.015). Leukocytosis was observed in 31% (5/16) of the patients on day 1 and in 80% (4/5) on day 21. Transient leukopenia developed in 6% (1/16) of the patients on day 1 and in 13% (1/8) on day 8. None of the patients had neutropenia. Lymphopenia was a prominent feature with a rate of 44% (7/16) of the patients on day 1 and 60% (3/5) on day 21. Lymphocytosis was not a feature of MERSāCoV infection. Thrombocytopenia developed in 31% (5/16) of the patients on day 1 and 40% (2/5) on day 21. Thrombocytosis was not a prominent feature and was observed in 6% (1/16) of the patients on day 1 and 17% (1/6) on day 9.
Conclusions
Patients with MERSāCoV infection showed variable hematologic parameters over time. Lymphocytosis and neutropenia were not features of MERSāCoV infection
Channel Impulse Response-based Distributed Physical Layer Authentication
In this preliminary work, we study the problem of {\it distributed}
authentication in wireless networks. Specifically, we consider a system where
multiple Bob (sensor) nodes listen to a channel and report their {\it
correlated} measurements to a Fusion Center (FC) which makes the ultimate
authentication decision. For the feature-based authentication at the FC,
channel impulse response has been utilized as the device fingerprint.
Additionally, the {\it correlated} measurements by the Bob nodes allow us to
invoke Compressed sensing to significantly reduce the reporting overhead to the
FC. Numerical results show that: i) the detection performance of the FC is
superior to that of a single Bob-node, ii) compressed sensing leads to at least
overhead reduction on the reporting channel at the expense of a small
( dB) SNR margin to achieve the same detection performance.Comment: 6 pages, 5 figures, accepted for presentation at IEEE VTC 2017 Sprin
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