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Purpose. When performing perimetry, refracting subjects with central visual field loss, and in emmetropization studies, it is important to accurately measure peripheral refractive errors. Traditional methods for foveal refraction often give uncertain results in eccentric angles as a result of the large aberrations and the reduced retinal function. The aim of this study is therefore to compare and

The dynamics of adsorption and desorption of uncharged homopolymers have been investigated using a coarse-grained model comprised of a bead-spring chain and a planar surface. Brownian dynamics simulation has been used to examine the adsorption process for polymers released near the surface and with bulk properties as well as Monte Carlo simulations to explore equilibrium adsorption structures of t

An annotated list of the known vascular plants of Andros is provided, with notes on ecological preferences, altitudinal distributions and frequency. The total number of native and naturalized taxa of vascular plants listed is 1055. Exact localities are provided for the rarest species on the island. 74 maps are also provided for species with variously delimited distribution. For the species known t

Since about 25 years ago work has been dedicated to the development of hydrodynamical model atmospheres for cool stars (of A to T spectral type). Despite their obviously sounder physical foundation in comparison with standard hydrostatic models, their general application has been rather limited. In order to understand why this is, and how to progress, we review the present status of hydrodynamical

Six Brachyspira type and reference strains, and 14 well characterized porcine field isolates representing all recognised porcine Brachyspira spp. were compared by different molecular methods. Sequence analysis of the 16S rRNA and the nox genes, pulsed-field gel electrophoresis (PFGE) and randomly amplified polymorphic DNA (RAPD) were used in the study. In addition the isolates were analysed by fiv

When designing symmetric ciphers, security and performance are of utmost importance. When selecting a symmetric encryption algorithm, the first choice is whether to choose a block cipher or a stream cipher. Most modern block ciphers offer a sufficient security and a reasonably good performance. But a block cipher must usually be used in a stream cipher mode of operation, which suggests that using

Understanding the mechanisms governing chemical and morphological changes induced by an ambient-pressure gas and how such changes influence the activity of heterogeneous catalysts is central to the formation of a predictive capability for structure-reactivity relationships. With techniques such as ambient-pressure photoelectron spectroscopy, scanning tunneling microscopy, and surface X-ray diffrac

AimTo reconstruct spatial and temporal patterns of European fire activity during the Holocene and to explore their potential drivers, by relating biomass burning to simulated biotic and abiotic parameters. LocationEurope. MethodsHolocene fire activity was investigated based on 156 sedimentary charcoal records from lakes and peat bogs across Europe. Charcoal data covering the last 9000 years were s

The African humid tropical biome constitutes the second largest rainforest region, significantly impacts global carbon cycling and climate, and has undergone major changes in functioning owing to climate and land-use change over the past century. We assess changes and trends in CO2 fluxes from 1901 to 2010 using nine land surface models forced with common driving data, and depict the inter-model v

One of the largest sources of uncertainties in modelling of the future global climate is the response of the terrestrial carbon cycle. Studies have shown that it is likely that the extant land sink of carbon will weaken in a warming climate. Should this happen, a larger portion of the annual carbon dioxide emissions will remain in the atmosphere, and further increase global warming, which in turn

Aim The northern limits of temperate broadleaved species in Fennoscanndia are controlled by their requirements for summer warmth for successful regeneration and growth as well as by the detrimental effects of winter cold on plant tissue. However, occurrences of meteorological conditions with detrimental effects on individual species are rare events rather than a reflection of average conditions. W

Recent OSL dating of various Late Quaternary deposits in Sweden has resulted in several sets of ages that appear inconsistent with geological interpretation; they usually overestimate the expected age. We explore the problems and potential of OSL-dating in Sweden by analysing quartz-OSL-ages from several known-age sites in Sweden and by investigating their luminescence properties. Two difficulties

Using population-wide data on inventors and their demographic characteristics, the paper analyzes trends and patterns by technologies in age, the level of education, and gender gap. We find that the education level of inventors has risen over time. We also find that the gender gap is closing but at slower pace than in other comparable areas of society. Much to our surprise, the average age of inve

We present pollen-based reconstructions of the spatio-temporal dynamics of northern European regional vegetation abundance through the Holocene. We apply the Regional Estimates of VEgetation Abundance from Large Sites (REVEALS) model using fossil pollen records from eighteen sites within five modern biomes in the region. The eighteen sites are classified into four time-trajectory types on the basi

Microalbuminuria is an established marker of systemic endothelial dysfunction, which for patients with diabetes signals an increased risk of both diabetic nephropathy and cardiovascular complications. A better understanding of the pathogenesis of microalbuminuria is important in the quest of finding new approaches to treat patients with diabetes. Direct acute effects of episodes of hyperglycaemia

Resolving the spatial and temporal dynamics of gross primary productivity (GPP) of terrestrial ecosystems across different scales remains a challenge. Remote sensing is regarded as the solution to upscale point observations conducted at the ecosystem level, using the eddy covariance (EC) technique, to the landscape and global levels. In addition to traditional vegetation indices, the photochemical