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A previous study detected mixing of two deeply split mtDNA clades (Clade I and Clade II) for Atlantic and Mediterranean populations of the medusozoan Pelagia noctiluca. The north hemisphere glaciations and the Messinian salinity crisis have been proposed as the two main biogeographic events related to the isolation between the Atlantic Ocean and the Mediterranean Sea. We tested if the splitting time between Clade I and Clade II of P. noctiluca was associated with one of these geological events. Our study was based on DNA sequence data of mitochondrial (COI and 16S ribosomal RNA) and nuclear (18S ribosomal RNA, internal transcribed spacer 1 and 5.8S ribosomal RNA) genes from populations of the Atlantic and Pacific Ocean and the Mediterranean Sea. The rise of the Isthmus of Panama was used to calibrate substitution rates for COI. This calibration was based on the detection of a shallow but significant genetic structure between P. noctiluca populations from the Pacific and the Atlantic Oceans. Considering our calibration for COI, we refute a possible origin of Clades I and II during the Messinian salinity crisis. Our estimates suggest the origin for a putative common ancestor of Clades I and II around 2.57 Ma (with 95% 2.91–2.22 HPD), roughly corresponding to the Gelasian stage of the early Pleistocene. These alterations include changes in the sea level and oceanic currents at the Strait of Gibraltar and other regions of the Mediterranean basin, and could explain the origin of the two P. noctiluca clades.
We give sufficient conditions for the non-triviality of the Poisson boundary of random walks on
and its subgroups. The group
is the group of piecewise projective homeomorphisms over the integers defined by Monod [Groups of piecewise projective homeomorphisms. Proc. Natl Acad. Sci. USA110(12) (2013), 4524–4527]. For a finitely generated subgroup
, we prove that either
is solvable or every measure on
with finite first moment that generates it as a semigroup has non-trivial Poisson boundary. In particular, we prove the non-triviality of the Poisson boundary of measures on Thompson’s group
that generate it as a semigroup and have finite first moment, which answers a question by Kaimanovich [Thompson’s group
is not Liouville. Groups, Graphs and Random Walks (London Mathematical Society Lecture Note Series). Eds. T. Ceccherini-Silberstein, M. Salvatori and E. Sava-Huss. Cambridge University Press, Cambridge, 2017, pp. 300–342, 7.A].
Assessing the impact of design automation on design practice prior to its implementation is difficult and subject to uncertainties. One reason for this is the designers' lack of knowledge about design automation. In this work, an industrial case study focusing on conceptual design of hydraulic circuits is conducted to assess the impact of the designers' knowledge on design automation potential estimation. In particular, the impact of demonstrating a prototypical implementation of a design automation application is investigated as a means to enhance the designers' knowledge about design automation. In this respect, a given set of metrics is rated twice to enable a comparative study: prior to and after introducing the design automation prototype. The yielded results show that the knowledge impacts the rating and supports reliability of potential estimation. Further, it is shown that designers acknowledge design automation potential for the early stages of design given sufficient knowledge about design automation. Yet, the results also indicate that careful attention needs to be put on the aspects covered by the prototype in order to avoid biasing participants.
In the past, the Court of Justice of the European Union (CJEU) has been one of the driving forces ensuring the compliance of secondary acts adopted under the Common European Asylum System (CEAS) with fundamental rights issues. It even came to be considered a ‘ fundamental rights ‘ Court, often taking a progressive stance in interpreting the relevant norms in light of the Charter of Fundamental Rights (CFREU) and other applicable human and refugee rights norms. While the Court has always been eager to demonstrate its legal integrity preventing second thoughts on its political independence, the proclaimed ‘ refugee crisis ‘ of the last years with the surrounding political turmoil seems to have had an impact on the Court and its approach towards the protection of fundamental rights within the European Union (EU) as well. This article seeks to analyse two judgments X and X and A.S. and Jafari considered exemplary for the shift the CJEU has undergone in the last years. In both cases, the CJEU has had the opportunity to change the course of the CEAS ensuring its compliance with fundamental rights standards. However, as will be shown below, the Court in 2017 has adopted a conservative if not politically motivated approach to CEAS cases.
When in 2015 more than one million people arrived at the shores of the EU, policy makers were quick in proclaiming it a ‘ migration ‘ or ‘ refugee crisis ‘. While 3,771 reported deaths in the Mediterranean and other related tragedies triggered only modest expressions of condolences, the increasing numbers of people applying for asylum provoked a chain reaction with mostly emotional, populist and fear-induced policies adopted at the Member States (MS) level. The crisis rhetoric surrounding the arrivals of people seeking international protection supported the renaissance of unilateral approaches, and soon those arrivals became the stress test for the European project as a whole. With the temporary reintroduction of internal border controls by several MS, the Union seemed to be rudely awakened from its Schengen dream, and the story of the ever-closer Union seemed to have come to an end. One reason why the Union was shaken to the core by the events of 2015 was that structural deficiencies of the CEAS surfaced and revealed that the EU is far from having accomplished a coherent set of norms in the field of asylum.
Fear of falling in Parkinson's disease (PD) has been suggested as predictor of future falling. The purpose of this study was to compare fear of falling score after two years of follow-up with those observed at baseline and to assess factors associated with change in fear of falling over time.
A total of 120 consecutive persons with PD were recruited and followed for two years. Fear of falling was assessed by using the 10-item Falls Efficacy Scale (FES). Occurrence of falling was registered during the first year of follow-up.
After two years, the average FES score statistically significantly changed (p = 0.003) from 30.5 to 37.5 out of 100 (increase of 22.9%). We observed that median scores of all FES items, except for “Preparing a meal, not requiring carrying of heavy or hot objects” and “Personal grooming,” significantly increased after two-year follow-up. After accounting for age, gender, PD duration, levodopa dosage, Hoehn and Yayhr stage, Unified Parkinson's Disease Rating Scale score three, depression, anxiety, and falling, we observed that sustaining greater number of falls in the first year of follow-up was associated with higher increase in FES score after two years (odds ratio 3.08, 95% confidence interval 1.30–4.87).
After two years of follow-up, we observed a decrease in confidence at performing nearly all basic daily activities. Fall prevention programs should be prioritized in management of PD.
The paper outlines the space-weather-related observations, instrumentation, research and service developments carried out at the Geophysical Centre of the Royal Meteorological Institute (RMI) in Dourbes, Belgium.
The role of schools in providing community-based support for children's mental health and well-being is widely accepted and encouraged. Research has mainly focused on designing and evaluating specific interventions and there is little data available regarding what provision is available, the focus and priorities of schools and the professionals involved in providing this support. The current study presents these data from schools in 10 European countries.
Online survey of 1466 schools in France, Germany, Ireland, Netherlands, Poland, Serbia, Spain, Sweden, UK and Ukraine. The participating countries were chosen based on their geographical spread, diversity of political and economic systems, and convenience in terms of access to the research group and presence of collaborators.
Schools reported having more universal provision than targeted provision and there was greater reported focus on children who already have difficulties compared with prevention of problems and promotion of student well-being. The most common interventions implemented related to social and emotional skills development and anti-bullying programmes. Learning and educational support professionals were present in many schools with fewer schools reporting involvement of a clinical specialist. Responses varied by country with 7.4–33.5% between-country variation across study outcomes. Secondary schools reported less support for parents and more for staff compared with primary schools, with private schools also indicating more staff support. Schools in rural locations reported less student support and professionals involved than schools in urban locations.
The current study provides up-to-date and cross-country insight into the approaches, priorities and provision available for mental health support in schools; highlighting what schools prioritise in providing mental health support and where coverage of provision is lacking.
The object of our investigation was to study a mechanism of water formation in the Surdulica geothermal system (recharge area, age and homogeneity of the waters). We collected 56 samples to determine the chemical, stable isotope, 14C and tritium content of the waters. We found large stable isotope variations in precipitation collected at different altitudes, whereas the geothermal waters are largely homogeneous and seasonally independent. Data on springs and rivers, the local meteoric water line and recharge area were obtained. Three groups of groundwater were identified by age – modern from natural springs, old from mines and very old from the Vranjska Banja. Because the initial 14C activity of infiltrated waters from the recharge area is unknown, the age of thermal waters can only be inferred, from HCO3−, 14C and 3H content, to be 10,000 to 28,000 years old.
Design grammars enable the formal representation of a vocabulary and rules that describe how designs can be synthesized just as the grammar rules of a spoken language define how to formulate valid, i.e., grammatically correct, sentences. Design grammars have been successfully applied in numerous engineering disciplines and enable the automated synthesis of designs within a defined design language. Design grammar development, however, is challenging and lacks methodological support. In this paper, a novel method is presented that supports the development and application of design grammars using transition graphs. In these, nodes represent generated designs and edges represent grammar rules that transform one design into another. Rather than using a tree structure to represent the possible application of rules, transition graphs are automatically generated and used to help designers better understand the developed grammar. The grammar designer is given feedback on (a) the rules, and (b) rule application sequences. This feedback can be used to (a) improve the grammar, and (b) apply it more efficiently. Two case studies, a gearbox synthesis task and a sliding tile puzzle, demonstrate the method. The results show the feasibility of the method to support design grammar development and application.
The Delta Scuti Network (DSN) is a collaboration of astronomers all around the globe who study and observe short-period variables. The field of scientific research includes high-precision photometric and Spectroscopic global campaigns, mode identification techniques, and asteroseismological pulsation modeling. We present results for three stars that are receiving the most attention at the moment: 4 CVn, BI CMi, and 44 Tau. Our results demonstrate that a large number of simultaneously excited nonradial oscillations in stars on and above the main sequence can be detected by conventional means.
We present the results of the multi-color, two-site observing campaign of β Cephei stars in the young open cluster NGC 4755, from 1999 and 2000. More than 200 hours of time-series photometric U, B, V filter data of the variable stars were acquired. We show a table of the detected frequencies and discuss the results.
β Cephei stars are early B-type stars which show periodic variations of luminosity, radial velocity and line profiles. They have periods between 2 and 7 hr. Their variability is now believed to be caused by the classical κ-mechanism operating in the heavy-element ionization zones. Many of the β Cephei stars are multimode pulsators, and radial as well as nonradial pulsation may occur. Advances in the last few years in both the observational and theoretical studies of multiple pulsation modes of δ Scuti stars have reached the stage that realistic comparisons of the results and examination of predictions can be carried out (Breger et al. 1998; Stankov et al. 1999). We now want to apply those asteroseismological methods to the much hotter β Cephei stars.
Using cultivation-dependant method, we isolated 184 strains from fresh and old bee bread, pollen, larvae and adults of solitary bee Osmia cornuta. The 16S rDNA sequencing of 79 selected isolates gave the final species-specific identification of strains. Phylogenetic analysis indicated that microbiota isolated from five different sources were represented with 29 species within three different phyla, Firmicutes with 25 species, Actinobacteria with only one species and Proteobacteria with three species of Enterobacteriaceae. Bacterial biodiversity presented with Shannon–Wiener index (H′) was highest in the alimentary tract of adults and old bee bread (H′ = 2.43 and H′ = 2.53, respectively) and in the same time no dominance of any species was scored. On the contrary, results obtained for Simpson index (D) showed that in pollen samples the dominant species was Pantoea agglomerans (D = 0.42) while in fresh bee bread that was Staphylococcus sp. (D = 0.27). We assume that microbial diversity detected in the tested samples of solitary bee O. cornuta probably come from environment.
Introduction. The fruit types such as raspberries (Rubus
idaeus), cherries (Prunus cerasus), blackberries
(Rubus fructicosus), blackthorns (Prunus spinosa) and
aronia (Aronia melanocarpa) are very common in Serbia. These fruit
species are a valuable source of antioxidants. The goal of our work was to evaluate the
antioxidant activities of ethyl acetate extracts of these five berries and to establish
possible correlation between the content of anthocyanin and the antioxidant activity.
Materials and methods. To determine antioxidant activity of the selected
fruits, the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, the ABTS
(2,2-azinobis-3 ethyl benzothiazoline-6-sulfonic acid) cation decolorization activity, the
FRAP (ferric reducing antioxidant power), and the TRP (total reducing power) were
measured. Results. The four methods selected for our assays showed strong
antioxidant properties for blackberry samples. The total anthocyanin content was estimated
using the pH differential method. The highest amount of anthocyanin was found in
blackberry samples [(1063.53 ± 0.01) mg·kg–1 fresh fruit], while the lowest was in
raspberry samples [(180.84 ± 0.02) mg·kg–1 fresh fruit]. The correlation between the
content of anthocyanin and antioxidant activity was established using regression analysis.
The highest correlation was found between total reducing power and total anthocyanin
(r = 0.97, p < 0.05). Hierarchical cluster analysis
divided selected fruit species into two statistically significant clusters.
Conclusion. Our results confirmed that analyzed berries are rich in
anthocyanins. A strong correlation among different assays as well as with anthocyanin
content was observed. Cluster analysis can be used in food science, to classify different
food types into groups, based on similarity among the results.
The mixture distributions for statistical time delay of electrical breakdown are proposed along with the generalized relation for the effective electron yield. The validity of the proposed model is tested by applying this distribution to experimental data measured in synthetic air at low pressure. Two samples without and with oxide surface are compared in order to determine physical processes leading to appearance of mixture distributions in the case of oxidized cathode. The obtained distributions are tested by Kolmogorov-Smirnov statistical hypothesis test in order to justify the use of mixture distributions. The physical interpretation of mixture distribution measured in the synthetic air is proposed, accompanied by the calculated values of the effective electron yield of initiating electrons in the gas gap.
Investigating forces driving the structure of aquatic communities has long been an important issue in ecology. In the present study, we focused on the effects of changed water supply for aquaculture ponds on phytoplankton, zooplankton and macrozoobenthos communities during two seasons of rearing common carp. We compared these communities between two types of inflow water: surface sources of water – a reservoir pond, two open wells and a small stream and groundwater – deep tube well. Significant changes were observed in environmental variables after the introduction of the groundwater source: oxygen concentration and water hardness decreased, while conductivity, phosphorus and un-ionized ammonia increased. Results revealed that all investigated groups, except Mollusca (macrozoobenthos), decreased in species richness, abundance and biomass due to changed water chemistry, but differed in the level of susceptibility. Rotifera and Cladocera were the most affected showing a sharp decline in density and number of species since 66% of species disappeared from the ponds. The abundance of Copepoda was relatively high although significantly lower under new conditions, with adults being more tolerant to changed inflow water than nauplii larvae. Phytoplankton had the highest potential to replace previous species with newcomers more adapted to changed water chemistry, providing 36 immigrant species, whereas 49 became extinct. Although mainly influenced by fish predation, Chironomidae (macrozoobenthos) were undoubtedly affected by changed water chemistry. These results suggest profound changes in three key ecological groups produced by significant changes of important environmental variables and water quality after the shift from surface to groundwater supply.
Fructose-rich diets (FRD) cause cardiac insulin resistance manifested by impairment of Akt/endothelial NO synthase (eNOS) signalling. In contrast, oestradiol (E2) activates this signalling pathway in the heart. To study the ability of E2 to revert the detrimental effect of fructose on cardiac Akt/eNOS, female rats were subjected to a FRD and ovariectomy followed with or without E2 replacement. We also analysed the effects of the FRD and E2 on cardiac extracellular signal-regulated kinase (Erk 1/2) signalling related to their role in cardiac hypertrophy development. Expression of Akt, eNOS and Erk 1/2, as well as regulatory phosphorylations of these molecules were determined. The protein expression of cardiac Akt and eNOS was not affected by the diet or E2 treatment. However, the FRD was accompanied by a decrease in Akt phosphorylation at Ser473 and Thr308, and eNOS at Ser1177, while the phosphorylation of eNOS at Thr495 was increased. E2 replacement in ovariectomised fructose-fed rats caused a reversion of the diet effect on Akt and eNOS serine phosphorylation, but mostly had no effect on threonine phosphorylation of the molecules. The FRD and E2 treatment did not influence Erk 1/2 expression and phosphorylation and heart mass as well. The data show that E2 selectively suppress the negative effects of a FRD on Akt/eNOS signalling and probably point to the different effects of E2 on kinase/phosphatase pathways responsible for phosphorylation/dephosphorylation of Akt and eNOS. Furthermore, the results suggest that the heart of females in the reproductive period is partially protected against the damaging effects of increased fructose intake.