239 research outputs found
Measurement of isotope shift in Eu II
The isotope shift between singly-charged ^Eu and ^Eu in the
4f^7(^8S^o)6s^9S_4-4f^7(^8S^o)6p_1/2>(J=4) transition at 4129 A has been
measured using fast ion beam-laser technique. This Eu line has attracted
interest in connection with efforts of obtaining a cosmochronometer based on
observed Th/Eu abundance ratios. Knowledge of the isotope shift is of
importance in order to check that contaminations from line blends do not
contribute to the line intensity of Eu II. The measured value of the isotope
shift -0.1527(2) cm-1 (= -4578 MHz) is consistent with the old spectroscopic
value of Krebs and Winkler -0.1503(25) cm-1 using a Fabry Perot interferometer,
while the accuracy is improved substantially.Comment: 12 pages, in press for Physica Scripta, in swete
Characteristics of equine summer eczema with emphasis on differences between Finnhorses and Icelandic horses in a 11-year study
Summer eczema, allergic dermatitis of the horse, was studied on 275 affected horses in Finland in 1997–2007. Features of the horses, clinical signs of the disease and owners' opinions of aggravating factors were recorded. Differences, especially, between two of the native Scandinavian horse breeds, the Finnhorse and the Icelandic horse, were evaluated. The study was based on clinical examination and information from the owners. Of the horses, 50% were Finnhorses, 26% Icelandic horses and 24% consisted of different breeds of ponies and other horses. Of the Finnhorses, 76% had summer eczema by the age of 5 years, but in the Icelandic horses born in Finland the average age at onset was 7 years. The vast majority of the horses, 75%, had moderate clinical signs, while 16% showed severe and 9% mild. The severity of clinical signs did not depend on the duration of the disease nor was it related to the age at onset. The only linkage to severity was the breed of the horse or import from Iceland; New Forest ponies and imported Icelandic horses showed severe clinical signs significantly more often than Finnhorses. Of the owners, 38% regarded insects as the only aggravating factor, 24% mentioned several simultaneous factors, including grass fodder and sunlight, while 22% could not specify any. In Finland, a typical horse breed suffering from summer eczema is the Finnhorse and the characteristics of the disease are mainly uniform with the other breeds affected. Equine summer eczema seems to be aggravated by various combinations of environmental factors
Anthropogenic and climatic impacts on a coastal environment in the Baltic Sea over the last 1000 years
Coastal environments have experienced large ecological changes as a result of human activities over the last 100-200 years. To understand the severity and potential consequences of such changes, paleoenvironmental records provide important contextual information. The Baltic Sea coastal zone is naturally a vulnerable system and subject to significant human-induced impacts. To put the recent environmental degradation in the Baltic coastal zone into a long-term perspective, and to assess the natural and anthropogenic drivers of environmental change, we present sedimentary records covering the last 1000 years obtained from a coastal inlet (Gasfjarden) and a nearby lake (Lake Storsjon) in Sweden. We investigate the links between a pollen-based land cover reconstruction from Lake Storsjon and paleoenvironmental variables from Gasfjarden itself, including diatom assemblages, organic carbon (C) and nitrogen (N) contents, stable C and N isotopic ratios, and biogenic silica contents. The Lake Storsjon record shows that regional land use was characterized by small-scale agricultural activity between 900 and 1400 CE, which slightly intensified between 1400 and 1800 CE. Substantial expansion of cropland was observed between 1800 and 1950 CE, before afforestation between 1950 and 2010 CE. From the Gasfjarden record, prior to 1800 CE, relatively minor changes in the diatom and geochemical proxies were found. The onset of cultural eutrophication in Gasfjarden can be traced to the 1800s and intensified land use is identified as the main driver. Anthropogenic activities in the 20th century have caused unprecedented ecosystem changes in the coastal inlet, as reflected in the diatom composition and geochemical proxies. (c) 2018 Elsevier Ltd. All rights reserved.Peer reviewe
Abundances of Mn, Co and Eu in a sample of 20 F-G disk stars: the influence of hyperfine structure splitting
We present Mn, Co and Eu abundances for a sample of 20 disk F and G dwarfs
and subgiants with metallicities in the range -0.8 <= [Fe/H] <= +0.3. We
investigate the influence of hyperfine structure (HFS) on the derived
abundances of Mn and Co by using HFS data from different sources in the
literature, as well as calculated HFS from interaction factors A and B. Eu
abundances were obtained from spectral synthesis of one Eu II line that takes
into account HFS from a series of recent laboratory measurements. For the lines
analyzed in this study, we find that for manganese, the differences between
abundances obtained with different HFSs are no larger than 0.10 dex. Our cobalt
abundances are even less sensitive to the choice of HFS than Mn, presenting a
0.07 dex maximum difference between determinations with different HFSs.
However, the cobalt HFS data from different sources are significantly
different. Our abundance results for Mn offer an independent confirmation of
the results from Prochaska & McWilliam (2000), who favour type Ia supernovae as
the main nucleosynthesis site of Mn production, in contrast to trends of Mn
versus metallicity previously reported in the literature. For Co, we obtain
[Co/Fe] ~ 0.0 in the range -0.3 < [Fe/H] < +0.3 and [Co/Fe] rising to a level
of +0.2 when [Fe/H] decreases from -0.3 to -0.8, in disagreement with recent
results in the literature. The observed discrepancies may be attributed to the
lack of HFS in the works we used for comparison. Our results for Eu are in
accordance with low-mass type II supernovae being the main site of the
r-process nucleosynthesis.Comment: 8 pages, 6 Postscript figures, accepted for publication in Astronomy
& Astrophysic
Effects of cognitive behavioral therapy for insomnia (CBT-I) on quality of life: a systematic review and meta-analysis
The effects of cognitive behavioral therapy for insomnia (CBT-I) have consistently been shown to improve insomnia symptoms and other health-related outcomes, but the effects on QoL have been inconsistent. Many factors including the type CBT-I delivery and type of instrument used to assess QoL make the topic complex. The present systematic review and meta-analysis synthesized the evidence of CBT-I efficacy on QoL outcomes across different populations, delivery modes, and methodological aspects.
Following the guidelines on preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), a literature search was conducted through PubMed, Web of Science, Scopus, and PsycINFO using keywords from relevant MeSH terms based on PICOS (Participants, Intervention, Comparison, Outcome and Study) criteria. Clinical trials investigating the effect of CBT-I as an intervention on QoL with any kind of control group were eligible if they reported mean scores and variation of QoL. Meta-analysis using a random-effect model was conducted to calculate the standardized mean differences (SMDs) in a set including all identified studies, as well as in three sub-sets: face-to-face CBT-I using randomized controlled trials (RCTs), online CBT-I using RCTs, and one-group pre- and post-treatment design.
A total of 24 studies comprising 1977 participants (808 in an intervention group) from 12 countries were eligible for meta-analysis. The overall pooled estimate of SMD of QoL when all 24 studies were included was 0.47 (95% CI: 0.22; 0.72; I2 = 84.5%; tau2 = 0.31; p < 0.001). The overall pooled estimate of SMD of QoL was 0.46 (95% CI: 0.01–0.90; I2 = 87.5%; tau2 = 0.48, p < 0.001) for intervention groups with face-to-face CBT-I compared to controls; 0.47 (95% CI: 0.02–0.92; I2 = 88.3%; tau2 = 0.36; p = 0.04) for intervention groups with digital CBT-I compared to controls, and 0.46 (95% CI: 0.12–0.80; I2 = 52.9%; tau2 = 0.07; p = 0.08) for one-group pre- and post-comparison using CBT-I intervention compared to baseline. Moreover, effects of CBT-I on QoL were different across populations (pooled SMD = 0.59 for patients with insomnia; 0.29 for patients with insomnia comorbid with another major disorder; and 0.48 for other conditions) and types of QoL instruments (pooled SMD = 0.36 for disease-specific QoL instrument not on insomnia, 0.43 for generic QoL instrument, and 0.67 for a single-QoL-item instrument). The probability of publication bias was ruled out in overall and design specific sub-group analysis based on funnel plot and Egger's test.
In conclusion, this meta-analysis confirmed a moderate, overall effect of CBT-I in improving QoL. However, due to small power and heterogeneity, future studies are needed to better explore the impact of moderating factors such as mode of delivery and type of QoL measure for assessment used
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A population-based dataset concerning predictors of willingness to get a COVID-19 vaccine in Iran
The global issue of preventing the spread of COVID-19 is challenging. One of the most efficient ways to control the pandemic is to have a full coverage of COVID-19 vaccination. Therefore, this paper collected survey data to understand the intention and willingness of COVID-19 vaccination uptake in Qazvin, Iran. With the use of a paper-and-pencil method and multistage stratified cluster sampling, research personnel approached and interviewed a representative sample of adults in Qazvin (n = 10843) between February 19 and April 9, 2021. The survey asked questions regarding sociodemographic information, fear of COVID-19, perceived COVID-19 infectability, perceived behavioral control over COVID-19 vaccination, subjective norm of COVID-19 vaccination, attitude towards COVID-19 vaccination, and intention to get COVID-19 vaccinated. The data collected from this survey were analyzed using descriptive statistics, which were carried out using the IBM SPSS version 17.0
Long-term land-cover/use change in a traditional farming landscape in Romania inferred from pollen data, historical maps and satellite images
Traditional farming landscapes in the temperate
zone that have persisted for millennia can be exceptionally species-rich and are therefore key conservation targets. In contrast to Europe’s West, Eastern Europe harbours widespread traditional farming landscapes, but drastic socio-economic and political changes in the twentieth century are likely to have impacted these landscapes profoundly. We reconstructed long-term land-use/cover and biodiversity changes over the last 150 years in a traditional farming landscape of outstanding species diversity in Transylvania. We used the Regional Estimates of Vegetation Abundance from Large Sites model applied to a pollen record from the Transylvanian Plain and a suite of historical and satellite-based maps. We documented widespread changes in the extent and location of grassland and cropland, a loss of wood pastures as well as a gradual increase in forest extent. Land management in the socialist period (1947–1989) led to grassland expansion, but grassland diversity decreased due to intensive production. Land-use intensity has declined since the collapse of socialism in 1989, resulting in widespread cropland abandonment and conversion to grassland. However, these trends may be
temporary due to both ongoing woody encroachment as
well as grassland management intensification in productive areas. Remarkably, only 8% of all grasslands existed throughout the entire time period (1860–2010), highlighting the importance of land-use history when identifying target areas for conservation, given that old-growth grasslands are most valuable in terms of biodiversity. Combining datasets from different disciplines can yield important additional insights into dynamic landscape and biodiversity changes, informing conservation actions to maintain these species-rich landscapes in the longer term
Explosion reactivity characterisation of pulverised torrefied spruce wood
Pulverised biomass is increasingly being used for power generation in 100% biomass plants or mixed with coal as a way of reducing greenhouse gas emissions. The fire and explosion hazards of pulverised wood and other agricultural waste materials have been recognised for some time. However, safety data for biomass are very scarce in the public literature, and non-existent for upgraded biomass products such as torrefied biomass. This is largely due to the challenges that biomass poses for explosion characterisation in the standard methods (1 m3 ISO vessel or 20 L sphere). The authors have developed and calibrated a new system for the 1 m3 ISO vessel that overcomes these challenges. In this work we present the first data in the open literature for the explosion characteristics of torrefied biomass. Results for untreated Norway spruce wood and Kellingley coal are also included for comparison. Flame speeds and post-explosion residue analysis results are also presented. Torrefied spruce wood was found to be more reactive than Kellingley coal and slightly more reactive than its parent material in terms of KSt, Pmax and flame speed. The differences between coal and biomass samples highlight that it should not be assumed that safety systems for coal can be applied to torrefied or raw wood materials without suitable modifications
Surrogate consent to non-beneficial research: erring on the right side when substituted judgments may be inaccurate
The same ELA class II risk factors confer equine insect bite hypersensitivity in two distinct populations
Insect bite hypersensitivity (IBH) is a chronic allergic dermatitis common in horses. Affected horses mainly react against antigens present in the saliva from the biting midges, Culicoides ssp, and occasionally black flies, Simulium ssp. Because of this insect dependency, the disease is clearly seasonal and prevalence varies between geographical locations. For two distinct horse breeds, we genotyped four microsatellite markers positioned within the MHC class II region and sequenced the highly polymorphic exons two from DRA and DRB3, respectively. Initially, 94 IBH-affected and 93 unaffected Swedish born Icelandic horses were tested for genetic association. These horses had previously been genotyped on the Illumina Equine SNP50 BeadChip, which made it possible to ensure that our study did not suffer from the effects of stratification. The second population consisted of 106 unaffected and 80 IBH-affected Exmoor ponies. We show that variants in the MHC class II region are associated with disease susceptibility (praw = 2.34 × 10−5), with the same allele (COR112:274) associated in two separate populations. In addition, we combined microsatellite and sequencing data in order to investigate the pattern of homozygosity and show that homozygosity across the entire MHC class II region is associated with a higher risk of developing IBH (p = 0.0013). To our knowledge this is the first time in any atopic dermatitis suffering species, including man, where the same risk allele has been identified in two distinct populations
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