What information patients require on graduated compression stockings.

Graduated compression stockings are used prophylactically on a variety of patients within acute hospitals. Anecdotal evidence suggests patients have a limited understanding of this treatment. The aim of this qualitative study was to explore patients' experiences of compression stockings and to ascertain perceptions of their use. Information was gathered using telephone interviews from a sample of 12 adults who had been patients within the past 2 months, and who had worn compression stockings for more than 48 hours. The results showed that patients received little or no information from healthcare staff regarding compression stockings, but that they did have knowledge from other sources, such as long-haul flight advice. This raises issues of informed consent and patient empowerment and highlights the need for both verbal and written information. The information gained informed a patient information leaflet, which was developed in partnership with a patient focus group.

The afterglow and elliptical host galaxy of the short gamma-ray burst GRB 050724.

Despite a rich phenomenology, gamma-ray bursts (GRBs) are divided into two classes based on their duration and spectral hardness--the long-soft and the short-hard bursts. The discovery of afterglow emission from long GRBs was a watershed event, pinpointing their origin to star-forming galaxies, and hence the death of massive stars, and indicating an energy release of about 10(51) erg. While theoretical arguments suggest that short GRBs are produced in the coalescence of binary compact objects (neutron stars or black holes), the progenitors, energetics and environments of these events remain elusive despite recent localizations. Here we report the discovery of the first radio afterglow from the short burst GRB 050724, which unambiguously associates it with an elliptical galaxy at a redshift z = 0.257. We show that the burst is powered by the same relativistic fireball mechanism as long GRBs, with the ejecta possibly collimated in jets, but that the total energy release is 10-1,000 times smaller. More importantly, the nature of the host galaxy demonstrates that short GRBs arise from an old (> 1 Gyr) stellar population, strengthening earlier suggestions and providing support for coalescing compact object binaries as the progenitors.

The afterglow of GRB 050709 and the nature of the short-hard gamma-ray bursts.

The final chapter in the long-standing mystery of the gamma-ray bursts (GRBs) centres on the origin of the short-hard class of bursts, which are suspected on theoretical grounds to result from the coalescence of neutron-star or black-hole binary systems. Numerous searches for the afterglows of short-hard bursts have been made, galvanized by the revolution in our understanding of long-duration GRBs that followed the discovery in 1997 of their broadband (X-ray, optical and radio) afterglow emission. Here we present the discovery of the X-ray afterglow of a short-hard burst, GRB 050709, whose accurate position allows us to associate it unambiguously with a star-forming galaxy at redshift z = 0.160, and whose optical lightcurve definitively excludes a supernova association. Together with results from three other recent short-hard bursts, this suggests that short-hard bursts release much less energy than the long-duration GRBs. Models requiring young stellar populations, such as magnetars and collapsars, are ruled out, while coalescing degenerate binaries remain the most promising progenitor candidates.

The impact of the Health Technology Board for Scotland's grading model on referrals to ophthalmology services.

AIM: To ascertain the impact of the Health Technology Board for Scotland's grading model on referrals to ophthalmology services. METHODS: An analysis was performed of the screening outcomes of 5575 consecutive patients, who were screened by the Grampian Diabetic Retinopathy Screening Programme between March and September 2003 according to the recommendations of the Health Technology Board and the Scottish Diabetic Retinopathy Grading Scheme 2003. RESULTS: 3066 (55%) were male. The median age was 65 years. 5.4% were passed on to the level 3 grader and 3.4% were finally referred to ophthalmology services. 2.3% required re-screening in 6 months; 85% were screened without mydriasis; 11.9% had ungradeable images despite a staged mydriasis protocol. Time to complete grading was 32 days (22-45). CONCLUSION: The impact of the Health Technology Board for Scotland's recommendations on referrals to ophthalmology services is modest and should be containable within existing resources.

Resolving the structure of ionized helium in the intergalactic medium with the far ultraviolet spectroscopic explorer.

The neutral hydrogen (H I) and ionized helium (He II) absorption in the spectra of quasars are unique probes of structure in the early universe. We present Far-Ultraviolet Spectroscopic Explorer observations of the line of sight to the quasar HE2347-4342 in the 1000 to 1187 angstrom band at a resolving power of 15,000. We resolve the He II Lyman alpha (Lyalpha) absorption as a discrete forest of absorption lines in the redshift range 2.3 to 2.7. About 50 percent of these features have H I counterparts with column densities N(H I) > 10(12.3) per square centimeter that account for most of the observed opacity in He II Lyalpha. The He II to H I column density ratio ranges from 1 to >1000, with an average of approximately 80. Ratios of <100 are consistent with photoionization of the absorbing gas by a hard ionizing spectrum resulting from the integrated light of quasars, but ratios of >100 in many locations indicate additional contributions from starburst galaxies or heavily filtered quasar radiation. The presence of He II Lyalpha absorbers with no H I counterparts indicates that structure is present even in low-density regions, consistent with theoretical predictions of structure formation through gravitational instability.

Heavy-element enrichment in low-density regions of the intergalactic medium.

Models for the composition of the diffuse intergalactic medium predict that low-density intergalactic gas at high redshift should be very poor in heavy elements. This is because locations of early star formation (and thus of heavy-element synthesis) and of gas delivery from such stars are located preferentially within higher-density regions of the intergalactic gas. Here we present a method for analysing carbon and oxygen absorption lines in quasar spectra that allows us to probe the heavy-element abundances at a redshift of three within low-density regions of intergalactic gas. We find that the ratio of triply ionized carbon to neutral hydrogen is roughly constant over a wide range of densities, and that, even as the density approaches zero, the ratio remains high. This unexpected enrichment of low-density gas in heavy elements suggests that early generations of small galaxies might be much more efficient at ejecting heavy elements into the intergalactic medium than has previously been thought.

A high deuterium abundance in the early Universe.

Intergalactic gas clouds at high redshifts have element abundances that are close to primordial. The ratio of deuterium to hydrogen (D/H) within such clouds-which is determined from absorption lines in the spectra of more distant quasars that lie along the same line of sight-provides the best estimate of the density of baryons (omegaB) in the Universe. Previous estimates of D/H in the early Universe have yielded values that differ by about an order of magnitude, with the lower values implying a high density of baryons that may be difficult to reconcile with both estimates of the primordial abundances of other light elements (especially 4He) and the known number of light neutrinos. The accuracy of such D/H determinations is heavily dependent on the inferred column density of neutral hydrogen in the absorbing clouds. Here we report an independent measurement of the neutral hydrogen column density in the cloud towards the quasar Q1937 - 1009, for which one of the low D/H values was derived. Our measurement requires a substantial revision to the D/H value reported previously; we obtain a lower limit of D/H > 4 x 10(-5) for this cloud, which implies omegaB < 0.016 for a Hubble constant of 100 km s(-1) Mpc(-1). This reduced upper limit for the baryon density relieves any conflict with standard Big Bang nucleosynthesis.

Faint galaxy surveys.

Various K band galaxy surveys have now established 2.2-m galaxy counts from K = 10 to K = 23. The K band counts rise slightly faster than a Euclidean slope to K = 17, at which point they turn over; beyond this magnitude, galaxies also become much bluer. Spectroscopic samples are available between K = 10 and 20 and show that the conventional distance laws hold rather precisely out to a redshift of about 0.6. Beyond this, galaxies appear fainter than expected. The results appear to favor rapid merging at modest galactic redshifts.