99 research outputs found
Performance of the optimized Post-Zel'dovich approximation for CDM models in arbitrary FLRW cosmologies
We investigate the performance of the optimized Post-Zel'dovich approximation
in three cold dark matter cosmologies. We consider two flat models with
(SCDM) and with (CDM) and an open model
with (OCDM). We find that the optimization scheme proposed by
Wei{\ss}, Gottl\"ober & Buchert (1996), in which the performance of the
Lagrangian perturbation theory was optimized only for the Einstein-de Sitter
cosmology, shows the excellent performances not only for SCDM model but also
for both OCDM and CDM models. This universality of the excellent
performance of the optimized Post-Zel'dovich approximation is explained by the
fact that a relation between the Post-Zel'dovich order's growth factor
and Zel'dovich order's one , , is insensitive to the
background cosmologies.Comment: 8 pages, 3 figures, LaTex using aaspp4.sty and epsf.sty, Accepted for
publication in ApJ Letter
Methods of assessment of patients for Nd:YAG laser capsulotomy that correlate with final visual improvement
BACKGROUND: This paper attempts to clarify the usefulness of various simple pre-operative measures in estimating the potential for a visually successful capsulotomy. METHODS: 24 patients attending for capsulotomy had pre-operative measures of glare with BAT tester, visibility of posterior pole and grading of posterior capsular pearls and fibrosis seen at slit lamp. Visual function was measured before and after standardised capsulotomy. Correlations of the various preoperative measures with eventual visual function improvements were calculated. RESULTS: Pearls at slit lamp and poor posterior pole visualisation were all correlated with improvements in visual acuity and contrast sensitivity after capsulotomy. Amount of fibrosis visible at slit lamp and glare assessment were not correlated with vision improvements after laser. CONCLUSION: Of the various measures that are taken prior to Nd : YAG capsulotomy, some correlate with eventual visual improvement but for others no clinical utility was found. Practitioners should note these findings as they are especially of use in more questionable or high-risk cases to help determine whether referral for PCO treatment by Nd: YAG capsulotomy is likely to benefit the patient
The summertime Boreal forest field measurement intensive (HUMPPA-COPEC-2010): an overview of meteorological and chemical influences
This paper describes the background, instrumentation, goals, and the regional influences on the HUMPPA-COPEC intensive field measurement campaign, conducted at the Boreal forest research station SMEAR II (Station for Measuring Ecosystem-Atmosphere Relation) in Hyytiälä, Finland from 12 July–12 August 2010. The prevailing meteorological conditions during the campaign are examined and contrasted with those of the past six years. Back trajectory analyses show that meteorological conditions at the site in 2010 were characterized by a higher proportion of southerly flow than in the other years studied. As a result the summer of 2010 was anomalously warm and high in ozone making the campaign relevant for the analysis of possible future climates. A comprehensive land use analysis, provided on both 5 and 50 km scales, shows that the main vegetation types surrounding the site on both the regional and local scales are: coniferous forest (Scots pine and/or Norway spruce); mixed forest (Birch and conifers); and woodland scrub (e.g. Willows, Aspen); indicating that the campaign results can be taken as representative of the Boreal forest ecosystem. In addition to the influence of biogenic emissions, the measurement site was occasionally impacted by sources other than vegetation. Specific tracers have been used here to identify the time periods when such sources have impacted the site namely: biomass burning (acetonitrile and CO), urban anthropogenic pollution (pentane and SO<sub>2</sub>) and the nearby Korkeakoski sawmill (enantiomeric ratio of chiral monoterpenes). None of these sources dominated the study period, allowing the Boreal forest summertime emissions to be assessed and contrasted with various other source signatures
Short-term effects of relaxation music on patients suffering from primary open-angle glaucoma
Thomas Bertelmann, Ilse Strempel Department of Ophthalmology, Philipps-University Marburg, Baldingerstraβe, Marburg, Germany Purpose: To evaluate whether additive relaxation music (RM) has an adjuvant short-term effect on physiological and psychological parameters in patients with primary open-angle glaucoma.Methods: Prospective, randomized clinical trial. Patients in the therapy group (TG) received a 30-minute RM via headphones, whereas members of the control group (CG) did not. Best corrected visual acuity, intraocular pressure, visual field testing, short- and long-term mental states, and blood levels of different stress hormones were analyzed and compared.Results: A total of 25 (61%)/16 (39%) patients were assigned to the TG/CG. Best corrected visual acuity, daily intraocular pressure, and short-term mental state (KAB) development were significantly better in the TG in comparison to controls. Visual field testing, long-term mental well-being (profile of mood states), and adrenalin, cortisol, and endothelin-I blood levels did not differ significantly between both groups.Conclusion: Additive RM applied on a daily basis can positively impact various physiological and psychological parameters in the short term. Keywords: primary open angle glaucoma, POAG, music therapy, intraocular pressure, IOP, mental healt
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