4,743 research outputs found
Long-term quality of life after en-bloc vertebrectomy: 25 patients followed up for 9Â years
AbstractObjectiveAssess quality-of-life results in patients who have undergone extensive curative surgery for spinal tumor and compare them to the general population in France.IntroductionLife expectancy is not the only criterion to assess the outcomes after massive tumor resections. Residual quality of life is also crucial. An indication for major surgery for spinal tumor should take the patient's long-term functional status into account, but the literature is limited on this question.Materials and methodsTwenty-five living patients from a group of 120 operated were assessed, all of whom were operated on by the same surgeon between 1984 and 2007. The mean follow-up was 9 years (range, 3â25 years). The mean age at surgery was 49 years. The patients completed different functional and quality-of-life questionnaires: the Oswestry Disability Index version 2 (ODI), the PROLO, the Karnofsky Index of performance status (KI), the Eastern Cooperative Oncology Group performance status (ECOG), the Short Form-36 Health Survey (SF-36), and the EuroQol-5 Dimensions (EQ5D). In addition, each patient was clinically and radiographically evaluated. Subgroups were identified considering the number of levels resected and histology. Their results on the SF-36 were compared with the results from the general population in France.ResultsThe mean PCS (physical component summary of the SF-36) was 52.4, the MCS (mental component summary, the psychological component of the SF-36) was 47.7, the ODI was 18.2, the PROLO was 7, the ECOG was 1, and the KI was 80%. The resections at three levels were associated with worse results in terms of quality of life, but overall, the results were similar to the French general population data for all categories of the SF-36.ConclusionAppropriate indications for massive spinal resection give good oncological and functional results. Although the expected life expectancy justifies this aggressive surgery, postoperative quality of life shows that it can also be successful on a functional level.Level of evidenceLevel IV; retrospective clinical study
An Overview of The VERITAS Prototype Telescope And Camera
VERITAS (the Very Energetic Radiation Imaging Telescope Array System) is the
next generation ground-based gamma-ray observatory that is being built in
southern Arizona by a collaboration of ten institutions in Canada, Ireland, the
U.K. and the U.S.A. VERITAS is designed to operate in the range from 50 GeV to
50 TeV with optimal sensitivity near 200 GeV; it will effectively overlap with
the next generation of space-based gamma-ray telescopes. The first phase of
VERITAS, consisting of four telescopes of 12 m aperture, will be operational by
the time of the GLAST launch in 2007. Eventually the array will be expanded to
include the full array of seven telescopes on a filled hexagonal grid of side
80 m. A prototype VERITAS telescope with a reduced number of mirrors and signal
channels has been built. Its design and performance is described here. The
prototype is scheduled to be upgraded to a full 499 pixel camera with 350
mirrors during the autumn of 2004.Comment: 8 pages, 6 figures, Proceedings of the Conference "The
Multiwavelength Approach to Unidentified Sources", to appear in the journal
Astrophysics and Space Scienc
Discovery of Very High-Energy Gamma-Ray Radiation from the BL Lac 1ES 0806+524
The high-frequency-peaked BL-Lacertae object \objectname{1ES 0806+524}, at
redshift z=0.138, was observed in the very-high-energy (VHE) gamma-ray regime
by VERITAS between November 2006 and April 2008. These data encompass the two-,
and three-telescope commissioning phases, as well as observations with the full
four-telescope array. \objectname{1ES 0806+524} is detected with a statistical
significance of 6.3 standard deviations from 245 excess events. Little or no
measurable variability on monthly time scales is found. The photon spectrum for
the period November 2007 to April 2008 can be characterized by a power law with
photon index between
300 GeV and 700 GeV. The integral flux above 300 GeV is
which corresponds to 1.8% of the Crab Nebula flux. Non contemporaneous
multiwavelength observations are combined with the VHE data to produce a
broadband spectral energy distribution that can be reasonably described using a
synchrotron-self Compton model.Comment: 14 pages, 4 figures, accepted to APJ
Towards a framework for critical citizenship education
Increasingly countries around the world are promoting forms of "critical" citizenship in the planned curricula of schools. However, the intended meaning behind this term varies markedly and can range from a set of creative and technical skills under the label "critical thinking" to a desire to encourage engagement, action and political emancipation, often labelled "critical pedagogy". This paper distinguishes these manifestations of the "critical" and, based on an analysis of the prevailing models of critical pedagogy and citizenship education, develops a conceptual framework for analysing and comparing the nature of critical citizenship
The Psychological Foundations of The Mediating Learning Support Assistant (MeLSA) Training Programme
It is estimated that a quarter of the mainstream school workforce in the UK are learning support staff. This is a substantial number of adults who have the potential to foster learning. This paper provides a brief summary regarding the impact of support staff on children and young peopleâs learning. It describes how the Mediating Learning Support Assistant (MeLSA) training programme was developed to meet a training gap identified in the literature. This paper also details the psychological theories and research evidence which provide the foundations for MeLSA and describes the format of the training programme, which consists of six days (mediating learning and mindset, thinking about thinking, memory and recall, mathematics, literacy, and implementation) followed by ongoing supervision. The aim of MeLSA is to ensure that learning support staff have the psychological and evidence-informed expertise to enable those with whom they are working to become competent and independent learners
VERITAS Upper Limit on the VHE Emission from the Radio Galaxy NGC 1275
The recent detection by the Fermi gamma-ray space telescope of high-energy
gamma-rays from the radio galaxy NGC 1275 makes the observation of the very
high energy (VHE: E > 100 GeV) part of its broadband spectrum particularly
interesting, especially for the understanding of active galactic nuclei (AGN)
with misaligned multi-structured jets. The radio galaxy NGC 1275 was recently
observed by VERITAS at energies above 100 GeV for about 8 hours. No VHE
gamma-ray emission was detected by VERITAS from NGC 1275. A 99% confidence
level upper limit of 2.1% of the Crab Nebula flux level is obtained at the
decorrelation energy of approximately 340 GeV, corresponding to 19% of the
power-law extrapolation of the Fermi Large Area Telescope (LAT) result.Comment: Accepted for publication in ApJ Letter
Detection of Extended VHE Gamma Ray Emission from G106.3+2.7 with VERITAS
We report the detection of very-high-energy (VHE) gamma-ray emission from
supernova remnant (SNR) G106.3+2.7. Observations performed in 2008 with the
VERITAS atmospheric Cherenkov gamma-ray telescope resolve extended emission
overlapping the elongated radio SNR. The 7.3 sigma (pre-trials) detection has a
full angular extent of roughly 0.6deg by 0.4deg. Most notably, the centroid of
the VHE emission is centered near the peak of the coincident 12CO (J = 1-0)
emission, 0.4deg away from the pulsar PSR J2229+6114, situated at the northern
end of the SNR. Evidently the current-epoch particles from the pulsar wind
nebula are not participating in the gamma-ray production. The VHE energy
spectrum measured with VERITAS is well characterized by a power law dN/dE =
N_0(E/3 TeV)^{-G} with a differential index of G = 2.29 +/- 0.33stat +/-
0.30sys and a flux of N_0 = (1.15 +/- 0.27stat +/- 0.35sys)x 10^{-13} cm^{-2}
s^{-1} TeV^{-1}. The integral flux above 1 TeV corresponds to ~5 percent of the
steady Crab Nebula emission above the same energy. We describe the observations
and analysis of the object and briefly discuss the implications of the
detection in a multiwavelength context.Comment: 5 pages, 2 figure
Evidence for long-term Gamma-ray and X-ray variability from the unidentified TeV source HESS J0632+057
HESS J0632+057 is one of only two unidentified very-high-energy gamma-ray
sources which appear to be point-like within experimental resolution. It is
possibly associated with the massive Be star MWC 148 and has been suggested to
resemble known TeV binary systems like LS I +61 303 or LS 5039. HESS J0632+057
was observed by VERITAS for 31 hours in 2006, 2008 and 2009. During these
observations, no significant signal in gamma rays with energies above 1 TeV was
detected from the direction of HESS J0632+057. A flux upper limit corresponding
to 1.1% of the flux of the Crab Nebula has been derived from the VERITAS data.
The non-detection by VERITAS excludes with a probability of 99.993% that HESS
J0632+057 is a steady gamma-ray emitter. Contemporaneous X-ray observations
with Swift XRT reveal a factor of 1.8+-0.4 higher flux in the 1-10 keV range
than earlier X-ray observations of HESS J0632+057. The variability in the
gamma-ray and X-ray fluxes supports interpretation of the ob ject as a
gamma-ray emitting binary.Comment: 8 pages, 3 figures, Accepted for publication in The Astrophysical
Journa
Photoelectrochemical properties of mesoporous NiOx deposited on technical FTO via nanopowder sintering in conventional and plasma atmospheres
Nanoporous nickel oxide (NiO x ) has been deposited with two different procedures of sintering (CS and RDS). Both samples display solid state oxidation at about 3.1 V vs Li+/Li. Upon sensitization of CS/RDS NiO x with erythrosine b (ERY), nickel oxide oxidation occurs at the same potential. Impedance spectroscopy revealed a higher charge transfer resistance for ERY-sensitized RDS NiO x with respect to sensitized CS NiO x . This was due to the chemisorption of a larger amount of ERY on RDS with respect to CS NiO x . Upon illumination the photoinduced charge transfer between ERY layer and NiO x could be observed only with oxidized CS. Photoelectrochemical effects of sensitized RDS NiO x were evidenced upon oxide reduction. With the addition of iodine RDS NiOx electrodes could give the reduction iodine â iodide in addition to the reduction of RDS NiO x . p-type dye sensitized solar cells were assembled with RDS NiO x photocathodes sensitized either by ERY or Fast Green. Resulting overall efficiencies ranged between 0.02 and 0.04 % upon irradiation with solar spectrum simulator (Iin : 0.1 W cm â2 )
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