Levels of State and Trait Anxiety in Patients Referred to Ophthalmology by Primary Care Clinicians: A Cross Sectional Study

Purpose There is a high level of over-referral from primary eye care leading to significant numbers of people without ocular pathology (false positives) being referred to secondary eye care. The present study used a psychometric instrument to determine whether there is a psychological burden on patients due to referral to secondary eye care, and used Rasch analysis to convert the data from an ordinal to an interval scale. Design Cross sectional study. Participants and Controls 322 participants and 80 control participants. Methods State (i.e. current) and trait (i.e. propensity to) anxiety were measured in a group of patients referred to a hospital eye department in the UK and in a control group who have had a sight test but were not referred. Response category analysis plus infit and outfit Rasch statistics and person separation indices were used to determine the usefulness of individual items and the response categories. Principal components analysis was used to determine dimensionality. Main Outcome Measure Levels of state and trait anxiety measured using the State-Trait Anxiety Inventory. Results State anxiety scores were significantly higher in the patients referred to secondary eye care than the controls (p0.1). Rasch analysis highlighted that the questionnaire results needed to be split into “anxiety-absent” and “anxiety-present” items for both state and trait anxiety, but both subscales showed the same profile of results between patients and controls. Conclusions State anxiety was shown to be higher in patients referred to secondary eye care than the controls, and at similar levels to people with moderate to high perceived susceptibility to breast cancer. This suggests that referral from primary to secondary eye care can result in a significant psychological burden on some patients

Temporally coherent luminance-to-luma mapping for high dynamic range video coding with H.264/AVC

This paper presents a technique for the efficient compression of high dynamic range video (HDR) sequences. Such video sequences usually represent several orders of magnitude of real-world luminance intensity levels. Therefore, they are mostly stored in a floating-point represention. In order to obtain a coded representation that is bit stream compatible with the H.264/AVC video coding standard, the float-valued HDR values have to be mapped to a suitable integer representation first. The mapping proposed in this paper is adapted to the dynamic range of each video frame. Furthermore, to compensate for the associated dynamic contrast variation across frames, a weighted prediction method and quantization adaptation are introduced. The experiments show that the proposed method offers highly efficient HDR video compression. Only a fraction of the bit rate of a non-adaptive reference method is required to represent an HDR video sequence at the same quality

INTER-SCALE PREDICTION OF MOTION INFORMATION FOR A WAVELET-BASED SCALABLE VIDEO CODER

In this paper we present an efficient inter-scale motion vector prediction scheme for a wavelet based scalable video codec which uses inter-scale wavelet prediction. The scalable video codec considered in our work belongs to the class of 2D+t+2D schemes which applies 2-D spatial wavelet transform on the input data first, motion compensated temporal transform second and further spatial decomposition at the last stage. Although inter-scale wavelet coefficient prediction is proven to be very efficient in this coding scheme, inter-scale motion prediction has not yet been analyzed in this context. We propose a prediction scheme that enables exploitation of interscale motion redundancy and significantly enhances coding efficiency. PSNR increase of up to 1.45 dB and side information rate savings of up to 13 % can be denoted, particularly for fast moving sequences. Index Terms — scalable video coding, motion prediction 1

Duration of the Snow Cover and the Need for Artificial Snow—A Challenge for Management in Ski-Centres of Serbia

The production and use of artificial snow has become necessary in most ski centres in Europe. The lack of snow creates problems in ski centres that were built without the prior valuation of natural factors. The survey covered winter tourist centres in Serbia, which are facing problems due to the shortening of the tourist season caused by the lack of snow cover on the ski slopes. The duration of the snow cover is the result of several factors. Air temperature changes were analysed in mountain tourist centres in Serbia, as well as at undeveloped destinations with a potential for snow sports. On the basis of the quantitative indicators of the air temperature and the methodology by means of which snowmaking is carried out, the time periods during the year for making artificial snow are presented. Due to the forecast rise in air temperature, the issue of profitability of artificial snow in the ski centres of Serbia remains open