2,491 research outputs found
A four-stage longitudinal study exploring pupils’ experiences, preparation and support systems during primary-secondary school transitions
Role of advanced technology in the detection of sight-threatening eye disease in a UK community setting.
Background/aims: To determine the performance of combinations of structural and functional screening tests in detecting sight-threatening eye disease in a cohort of elderly subjects recruited from primary care. Methods: 505 subjects aged ≥60 years underwent frequency doubling technology (FDT) perimetry, iVue optical coherence tomography (iWellness and peripapillary retinal nerve fibre layer (RNFL) scans) and intraocular pressure with the Ocular Response Analyzer, all performed by an ophthalmic technician. The reference standard was a full ophthalmic examination by an experienced clinician who was masked to the index test results. Subjects were classified as presence or absence of sight-threatening eye disease (clinically significant cataract, primary open-angle glaucoma, intermediate or advanced age-related macular degeneration and significant diabetic retinopathy). Univariate and multivariate logistic regression analyses were used to determine the association between abnormal screening test results and the presence of sight-threatening eye disease. Results: 171 subjects (33.8%) had one or more sight-threatening eye diseases. The multivariate analysis found significant associations with any of the target conditions for visual acuity of <6/12, an abnormal FDT and peripapillary RNFL thickness outside the 99% normal limit. The sensitivity of this optimised screening panel was 61.3% (95% CI 53.5 to 68.7), with a specificity of 78.8% (95% CI 74.0 to 83.1), a positive predictive value of 59.5% (95% CI 53.7 to 65.2) and an overall diagnostic accuracy of 72.9% (95% CI 68.8 to 76.8). Conclusions: A subset of screening tests may provide an accurate and efficient means of population screening for significant eye disease in the elderly. This study provides useful preliminary data to inform the development of further larger, multicentre screening studies to validate this screening panel
GPU Enhancement of the Trigger to Extend Physics Reach at the Large Hadron Collider
At the Large Hadron Collider (LHC), the trigger systems for the detectors
must be able to process a very large amount of data in a very limited amount of
time, so that the nominal collision rate of 40 MHz can be reduced to a data
rate that can be stored and processed in a reasonable amount of time. This need
for high performance places very stringent requirements on the complexity of
the algorithms that can be used for identifying events of interest in the
trigger system, which potentially limits the ability to trigger on signatures
of various new physics models. In this paper, we present an alternative
tracking algorithm, based on the Hough transform, which avoids many of the
problems associated with the standard combinatorial track finding currently
used. The Hough transform is also well-adapted for Graphics Processing Unit
(GPU)-based computing, and such GPU-based systems could be easily integrated
into the existing High-Level Trigger (HLT). This algorithm offers the ability
to trigger on topological signatures of new physics currently not practical to
reconstruct, such as events with jets or black holes significantly displaced
from the primary vertex. This paper presents, for the first time, an
implementation and preliminary performance results using NVIDIA Tesla C2075 and
K20c GPUs.Comment: 5 pages, 3 figures. Submitted to proceedings of the 20th
International Conference on Computing in High Energy and Nuclear Physics
(CHEP2013), Amsterda
Safety and effi cacy of insertion of supraglottic device in anaesthetised patients by fi rst-time users
Background: Over the years, several supraglottic devices have been developed, but the most recent one is the i-gel®. It is a new device with some distinctive features that set it apart from many of its competitors. This study was designed to determine the safety and efficacy of placing different airway devices by first-time users. Methods: Fifty volunteer doctors who are regularly involved in cardiopulmonary resuscitation and emergency medicine were divided into two groups on the basis of their experience and were timed to insert the two supraglottic devices, i-gel® and laryngeal mask airway (LMA), in ASA grade I, II and III anaesthetised patients under expert guidance. The haemodynamic parameters were recorded and the volunteers were asked to complete a questionnaire.Results: In both the groups, i-gel® was inserted in less time than LMA. The time taken for insertion of i-gel® by both the groups was not significant. The success rate of inserting i-gel® by both groups was not significant (p > 0.05). Ninety-six percent of participants in both the groups found that i-gel® was easier to insert and required minimal adjustment.Conclusion: Our results suggest that i-gel® is rapidly inserted by novices, and produces haemodynamic changes compared to those resulting from insertion of classic LMA. We suggest that the device is safe and can be used by first-time users and experts in cardiopulmonary resuscitation and in emergencies.Keywords: first-time users; laryngeal mask airway; i-ge
Primary intraosseous carcinoma of mandible: an update on review of literature with a case report
Primary intraosseous carcinoma (PIOC) is a rare malignant neoplasm of the jaws which is locally aggressive with
quite poor prognosis. Overall and disease free survival is poor with almost 50% patients failing within first 2 years
of follow up and reason can be attributed to the delayed diagnosis. But knowledge of the clinical, radiographic and
histopathologic features of PIOC allows accurate and early diagnosis of the lesion so that an early and appropriate
treatment can be instituted for better prognosis. Here a typical case of PIOC of the mandible is presented and an
attempt is made to discuss all possible differential diagnosis and an update on review of literature is presented. Our
case highlights that radiographic examination is one of the most effective methods for detecting early lesions of
PIOCs
Niobium oxide prepared through a novel supercritical-CO2-assisted method as a highly active heterogeneous catalyst for the synthesis of azoxybenzene from aniline
High-surface area Nb2O5 nanoparticles were synthesised by a novel supercritical-CO2-assisted method (Nb2O5-scCO2) and were applied for the first time as a heterogeneous catalyst in the oxidative coupling of aniline to azoxybenzene using the environmentally friendly H2O2 as the oxidant. The application of scCO2 in the synthesis of Nb2O5-scCO2 catalyst resulted in a significantly enhanced catalytic activity compared to a reference catalyst prepared without scCO2 (Nb2O5-Ref) or to commercial Nb2O5. Importantly, the Nb2O5-scCO2 catalyst achieved an aniline conversion of 86% (stoichiometric maximum of 93% with the employed aniline-to-H2O2 ratio of 1 : 1.4) with an azoxybenzene selectivity of 92% and with 95% efficiency in H2O2 utilisation in 45 min without requiring external heating (the reaction is exothermic) and with an extremely low catalyst loading (weight ratio between the catalyst and substrate, Rc/s = 0.005). This performance largely surpasses that of any other heterogeneous catalyst previously reported for this reaction. Additionally, the Nb2O5 catalyst displayed high activity also for substituted anilines (e.g. methyl or ethyl-anilines and para-anisidine) and was reused in consecutive runs without any loss of activity. Characterisation by means of N2-physisorption, XRD, FTIR and TEM allowed the correlation of the remarkable catalytic performance of Nb2O5-scCO2 to its higher surface area and discrete nanoparticle morphology compared to the aggregated larger particles constituting the material prepared without scCO2. A catalytic test in the presence of a radical scavenger proved that the reaction follows a radical pathway
RADIATIVE TRANSFER MODEL SIMULATIONS TO DETERMINE THE NIGHT TIME FOG DETECTION THRESHOLD
Every winter the Indo-Gangetic plains (IGP) of northern India are severely impacted both socially and economically by fog. For night time fog detection, visible imagery cannot be used. Also, as emissions from ground and fog is almost similar in thermal infrared (TIR, 10.8 μm) channel, TIR channel cannot help in identifying fog. However, emission in middle infrared (MIR, 3.9 μm) channel is less than emission in TIR channel over foggy area. Therefore, brightness temperature difference (BTD) between TIR and MIR is positive during night time over fog area. This BTD technique cannot be directly used during day time as MIR channel is contaminated by solar radiations. In the present work, a spectral sensitivity analysis study has been done for these two spectral channels using radiative transfer model (RTM) simulations to determine a threshold BTD for night time fog detection. SBDART (Santa Barbara DISORT Radiative Transfer) model was used for this study to simulate brightness temperatures (BT). The RTM simulations of BT of the two spectral channels was carried out for different fog microphysical characteristics like fog optical depth (FOD) and fog droplet size (Re). The fog episode of January 2018 over IGP was studied by applying threshold BTD obtained from simulation results for INSAT-3D data. A threshold BTD value > 5 K detected night time fog over IGP with good accuracy. The threshold BTD obtained from satellite image is compared with different cases established from simulation result which gave idea about microphysical properties of fog over IGP during winter seasons
Moving to Secondary School for Children with ASN:a systematic review of international literature
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