11,943 research outputs found
Optimization of multivariate analysis for IACT stereoscopic systems
Multivariate methods have been recently introduced and successfully applied
for the discrimination of signal from background in the selection of genuine
very-high energy gamma-ray events with the H.E.S.S. Imaging Atmospheric
Cerenkov Telescope. The complementary performance of three independent
reconstruction methods developed for the H.E.S.S. data analysis, namely Hillas,
model and 3D-model suggests the optimization of their combination through the
application of a resulting efficient multivariate estimator. In this work the
boosted decision tree method is proposed leading to a significant increase in
the signal over background ratio compared to the standard approaches. The
improved sensitivity is also demonstrated through a comparative analysis of a
set of benchmark astrophysical sources.Comment: 10 pages, 8 figures, 3 tables, accepted for publication in
Astroparticle Physic
Nanoparticles at liquid interfaces
This thesis is concerned with the study of two phase systems stabilised by nanometre sized solid particles. The understanding of how modifying these particles at the oil(air)-water interface can change the properties of the bulk systems they stabilise is important for a number of industrial applications including agrochemicals, pharmaceuticals, cosmetics, food technology, paints, paper processing and oil recovery.Each section of this work investigates a different solid-stabilised system. For each of these systems a novel way to change the properties of the system through modification of the particle behaviour at the fluid interface is identified, or a behaviour which is unique to solid-stabilised systems is investigated
Core binding factor (CBF) is required for Epstein-Barr virus EBNA3 proteins to regulate target gene expression
ChIP-seq performed on lymphoblastoid cell lines (LCLs), expressing epitope-tagged EBNA3A, EBNA3B or EBNA3C from EBV-recombinants, revealed important principles of EBNA3 binding to chromatin. When combined with global chromatin looping data, EBNA3-bound loci were found to have a singular character, each directly associating with either EBNA3-repressed or EBNA3-activated genes, but not with both. EBNA3A and EBNA3C showed significant association with repressed and activated genes. Significant direct association for EBNA3B loci could only be shown with EBNA3B-repressed genes. A comparison of EBNA3 binding sites with known transcription factor binding sites in LCL GM12878 revealed substantial co-localization of EBNA3s with RUNX3-a protein induced by EBV during B cell transformation. The beta-subunit of core binding factor (CBFβ), that heterodimerizes with RUNX3, could co-immunoprecipitate robustly EBNA3B and EBNA3C, but only weakly EBNA3A. Depletion of either RUNX3 or CBFβ with lentivirus-delivered shRNA impaired epitope-tagged EBNA3B and EBNA3C binding at multiple regulated gene loci, indicating a requirement for CBF heterodimers in EBNA3 recruitment during target-gene regulation. ShRNA-mediated depletion of CBFβ in an EBNA3C-conditional LCL confirmed the role of CBF in the regulation of EBNA3C-induced and -repressed genes. These results reveal an important role for RUNX3/CBF during B cell transformation and EBV latency that was hitherto unexplored
Deriving modified rankin scores from medical records
<p><b>Background and Purpose:</b> Modified Rankin score (mRS) is traditionally graded using a face-to-face or telephone interview. Certain stroke assessment scales can be derived from a review of a patient’s case-record alone. We hypothesized that mRS could be successfully derived from the narrative within patient case-records.</p>
<p><b>Methods:</b> Sequential patients attending our cerebrovascular outpatient clinic were included. Two independent, blinded clinicians, trained in mRS, assessed case-records to derive mRS. They scored “certainty” of their grading on a 5-point Likert scale. Agreement between derived and traditional face-to-face mRS was calculated using attribute agreement analysis.</p>
<p><b>Results:</b> Fifty patients with a range of disabilities were included. Case-record appraisers were poor at deriving mRS (k=0.34 against standard). Derived mRS grades showed poor agreement between observers (k=0.33). There was no relationship between certainty of derived mRS and proportion of correct grades (P=0.727).</p>
<p><b>Conclusion:</b> Accurate mRS cannot be derived from standard hospital records. Direct mRS interview is still required for clinical trials.</p>
Editorial: Starting a journal, starting a conversation
First paragraph: Starting up a new academic journal in the information age, an age characterised by an ongoing explosion of academic publishing around the globe, may seem like joining a bandwagon of the hopeful and reckless. It is an idea that many pursue and many such journals die quietly. But then, without a certain hope, without a certain degree of blind enthusiasm and unquestioning optimism many things would never happen, and many good outcomes would never occur or even be given energy and time. Starting up Other Education: The Journal of Educational Alternatives, is a risk worth taking for the sake of our remit and the conversations to be explored. What has made this sure for us is that wherever we have turned with this venture so far we have found help, support, interest and life
Editorial: The Academic Study of Educational Alternatives
First paragraph: Having just read some reflections on the first issue of Other Education (http://www.libed.org.uk/jan13/other-education.html), we consider it is a fitting place to springboard into this editorial. The review, speaking from a place of practical educational matters, voices concerns about the philosophical nature of some of the contributions in the inaugural issue of Other Education. As readers of this journal will see from the articles in this issue -- our first to include peer reviewed submissions -- Other Education is extremely concerned with practical educational matters. As stated and shown, with regard to the inaugural issue of invited position papers from the OE editorial board, our remit is broad. What we have done so far is to highlight perhaps that educational alternatives are a wide territory, requiring a theoretical basis and philosophical and theoretical debates, positions and challenges included in its conversations, in order to flourish. The mostly academic based editorial board that we work with are always theoreticians, even if not explicitly so, because academic work without some kind or some content of theory is missing a vital component of its presentation. As the stated aim of Other Education is "to promote and represent the academic study of educational alternatives" rather than to represent those practices and processes themselves (see http://www.othereducation.stir.ac.uk/index.php/OE/about/editorialPolicies#focusAndScope) our first priority is towards the publication of academic work. Such work inevitably needs to include a theoretical dimension-albeit that this does not necessarily mean that such a dimension has to be philosophical
Studies of the superconducting properties of Sn1-xInxTe (x=0.38 to 0.45) using muon-spin spectroscopy
The superconducting properties of Sn1-xInxTe (x = 0.38 to 0.45) have been
studied using magnetization and muon-spin rotation or relaxation (muSR)
measurements. These measurements show that the superconducting critical
temperature Tc of Sn1-xInxTe increases with increasing x, reaching a maximum at
around 4.8 K for x = 0.45. Zero-field muSR results indicate that time-reversal
symmetry is preserved in this material. Transverse-field muon-spin rotation has
been used to study the temperature dependence of the magnetic penetration depth
lambda(T) in the mixed state. For all the compositions studied, lambda(T) can
be well described using a single-gap s-wave BCS model. The magnetic penetration
depth at zero temperature lambda(0) ranges from 500 to 580 nm. Both the
superconducting gap Delta(0) at 0 K and the gap ratio Delta(0)/kBTc indicate
that Sn1-xInxTe (x = 0.38 to 0.45) should be considered as a superconductor
with intermediate to strong coupling.Comment: 7 pages, 6 figures, 3 table
Superconducting and normal-state properties of the noncentrosymmetric superconductor Re6Zr
We systematically investigate the normal and superconducting properties of
non-centrosymmetric ReZr using magnetization, heat capacity, and
electrical resistivity measurements. Resistivity measurements indicate
ReZr has poor metallic behavior and is dominated by disorder. ReZr
undergoes a superconducting transition at K. Magnetization measurements give a lower critical
field, mT. The
Werthamer-Helfand-Hohenberg model is used to approximate the upper critical
field T which is close to
the Pauli limiting field of 12.35 T and which could indicate singlet-triplet
mixing. However, low-temperature specific-heat data suggest that ReZr is
an isotropic, fully gapped s-wave superconductor with enhanced electron-phonon
coupling. Unusual flux pinning resulting in a peak effect is observed in the
magnetization data, indicating an unconventional vortex state.Comment: 11 pages, 7 figures, 2 table
Torsion–rotation global analysis of the first three torsional states (νt = 0, 1, 2) and terahertz database for methanol
Stimulated by recent THz measurements of the methanol spectrum in one of our laboratories, undertaken in support of NASA programs related to the Herschel Space Observatory (HSO) and the Atacama Large Millimeter Array (ALMA), we have carried out a global analysis of available microwave and high-resolution infrared data for the first three torsional states (νt = 0, 1, 2), and for J values up to 30. This global fit of approximately 5600 frequency measurements and 19 000 Fourier transform far infrared (FTFIR) wavenumber measurements to 119 parameters reaches the estimated experimental measurement accuracy for the FTFIR transitions, and about twice the estimated experimental measurement accuracy for the microwave, submillimeter-wave, and terahertz transitions. The present fit is essentially a continuation of our earlier work, but we have greatly expanded our previous data set and have added a large number of new torsion–rotation interaction terms to the Hamiltonian in our previously used computer program. The results, together with a number of calculated (but unmeasured) transitions, including their line strength, estimated uncertainty, and lower state energy, are made available in the supplementary material as a database formatted to be useful for astronomical searches. Some discussion of several open spectroscopic problems, e.g., (i) an improved notation for the numerous parameters in the torsion–rotation Hamiltonian, (ii) possible causes of the failure to fit frequency measurements to the estimated measurement uncertainty, and (iii) pitfalls to be avoided when intercomparing apparently identical parameters from the internal axis method and the rho axis method are also given
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