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NaNbO3:SrTiO3 interface nanolayers are studied by combining first-principles modeling and experimental approach. The nature of NaNbO3:SrTiO3 interface is investigated using density-functional theory calculations. Interface parameters are experimentally estimated using analysis of the dielectric response of SrTiO3 and NaNbO3 epitaxial films and NaNbO3:SrTiO3 superlattices. It is shown that NaNbO3:SrTiO3 interfaces can be approximated by dielectric nanolayers with thickness 1-2 nm and with temperature independent permittivity 25-55. Mechanism responsible for the nanolayer formation is the ionic charge mismatch between constituents. [ABSTRACT FROM AUTHOR]

We use computational and experimental methods to study d° ferromagnetism at a charge-imbalanced interface between two perovskites. In SrTi03/KTa03 superlattice calculations, the charge imbalance introduces holes in the SrTiO3 layer, inducing a d0 ferromagnetic half-metallic 2D hole gas at the interface oxygen 2p orbitals. The charge imbalance overrides doping by vacancies at realistic concentrations. Varying the constituent materials shows ferromagnetism to be a general property of hole-type d0 perovskite interfaces. Atomically sharp epitaxial d0 SrTi03/KTa03, SrTi03/KNb03, and SrTi03/NaNb03 interfaces are found to exhibit ferromagnetic hysteresis at room temperature. We suggest that the behavior is due to the high density of states and exchange coupling at the oxygen tig band in comparison with the more studied d band t2g symmetry electron gas. [ABSTRACT FROM AUTHOR]

Objectives: Excessive consumption of sugar-sweetened beverages (SSBs) contributes to adverse health outcomes but is differentiated by socio-economic indicators. The study analyses the educational disparities in adults frequent consumption of sugar-sweetened beverages (SSBs) in Estonia and its temporal changes between 2006 and 2022., Study Design: Repeated cross-sectional survey., Methods: Nationally representative data from 9 biennial cross-sectional surveys on 25-64-year-old Estonian residents (n = 20396) was used for the study. Changes in frequent (on 6-7 days per week) consumption of SSBs by study year, sex, age, and education is analysed using descriptive statistics and binomial logistic regression. Prevalence and odds ratios (OR) with 95 % confidence intervals (CIs) are presented focusing on temporal and educational patterns in frequent SSB consumption., Results: The prevalence of frequent SSB consumption among Estonian adults declined consistently from 2006 (14.0 %) to 2018 (5.2 %), followed by statistically non-significant increases in 2020 (6.8 %) and 2022 (7.1 %). Prevalence of frequent SSB consumption was significantly (p < 0.01) higher among adults with primary or lower education (12.4 %) compared to tertiary education group (4.8 %). The educational differences in SSB consumption (12.4 % in primary or lower vs. 4.8 % in tertiary education) were nearly three-fold after adjusting for sex, age, and period effects (OR 2.84, 95 % CI 1.71-4.74) and have been consistent since 2010., Conclusions: Although frequent consumption of SSBs has been generally decreasing among Estonian adults, the findings illustrate the persisting educational gradients in exposure that expectedly translates into socio-economic inequalities in adverse health outcomes resulting from excessive SSB consumption., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd on behalf of The Royal Society for Public Health.)

After a strong demographic decline before World War II, wild boar populations are expanding and the species is now the second-most abundant ungulate in Europe. This increase raises concerns due to wild boar impact on crops and natural ecosystems and as potential vector of diseases. Additionally, wild boar can hybridize with domestic pigs, which could increase health risks and alter wild boar adaptive potential. We analysed 47,148 Single Nucleotide Polymorphisms in wild boar from Europe (292) and the Near East (16), and commercial (44) and local (255) pig breeds, to discern patterns of hybridization across Europe. We identified 33 wild boars with more than 10% domestic ancestry in their genome, mostly concentrated in Austria, Bosnia and Herzegovina, Bulgaria and Serbia. This difference is probably due to contrasting practices, with free-ranging vs. industrial farming but more samples would be needed to investigate larger geographic patterns. Our results suggest hybridization has occurred over a long period and is still ongoing, as we observed recent hybrids. Although wild and domestic populations have maintained their genetic distinctiveness, potential health threats raise concerns and require implementation of management actions and farming practices aimed at reducing contact between wild and domestic pigs.

Supplementary feeding is widely used in game management but may aid the transmission of parasites. Firstly, feeding sites attract animals and may be regarded as high-risk areas for parasite transmission. Secondly, high host population densities resulting from and supported by supplementary feeding, as well as accumulation of parasites in the environment, may increase parasite prevalence. Our aim was to investigate whether host density or the number of feeding sites drives endoparasite infection in an Estonian wild boar (Sus scrofa) population. For this, we collected wild boar faeces from forests, and soil samples from supplementary feeding sites in central and south-eastern Estonia. The role of host density and number of feeding sites on both the risk and mean abundance of endoparasite infection was modelled using generalized linear models (GLM). The presence of biohelminths in faecal samples was associated with both wild boar and feeding site density, whereas the presence of Eimeria sp. oocysts in faecal samples was only associated with wild boar density. Helminth eggs were found more often from the soil of active and abandoned feeding sites than from control areas. This could reflect parasitic contamination or indicate that supplementary feeding sites are suitable habitat for soil-dwelling nematodes. These results suggest that the effects of supplementary feeding on parasite prevalence in wild boar are mediated by the characteristics of parasite life cycles.

Capercaillie (Tetrao urogallus) and other grouse species represent conservation concerns across Europe due to their negative abundance trends. In addition to habitat deterioration, predation is considered a major factor contributing to population declines. While the role of generalist predators on grouse predation is relatively well known, the impact of the omnivorous wild boar has remained elusive. We hypothesize that wild boar is an important predator of ground-nesting birds, but has been neglected as a bird predator because traditional morphological methods underestimate the proportion of birds in wild boar diet. To distinguish between different mammalian predator species, as well as different grouse prey species, we developed a molecular method based on the analysis of mitochondrial DNA that allows accurate species identification. We collected 109 wild boar faeces at protected capercaillie leks and surrounding areas and analysed bird consumption using genetic methods and classical morphological examination. Genetic analysis revealed that the proportion of birds in wild boar faeces was significantly higher (17.3%; 4.5×) than indicated by morphological examination (3.8%). Moreover, the genetic method allowed considerably more precise taxonomic identification of consumed birds compared to morphological analysis. Our results demonstrate: (i) the value of using genetic approaches in faecal dietary analysis due to their higher sensitivity, and (ii) that wild boar is an important predator of ground-nesting birds, deserving serious consideration in conservation planning for capercaillie and other grouse.

Supplementary feeding of ungulates, being widely used in game management, may have unwanted consequences. Its role in agricultural damage is well-studied, but few studies have considered the potential for the practice to attract ground nest predators. Our goal was to identify the factors influencing ground nest predation in the vicinity of year-round supplementary feeding sites for wild boar and to characterise their spatiotemporal scope. We conducted two separate artificial ground nest experiments in five different hunting districts in south-eastern Estonia. The quantity of food provided and distance of a nest from the feeding site were the most important factors determining predation risk. Larger quantities of food resulted in higher predation risk, while predation risk responded in a non-linear fashion to distance from the feeding site. Although predation risk eventually decreases if supplementary feeding is ceased for at least four years, recently abandoned feeding sites still pose a high predation risk.

Background: Echinococcus granulosus and E. multilocularis are tapeworm parasites of major medical and veterinary importance, causing cystic and alveolar echinococcosis, respectively. Both diseases are listed among the most severe parasitic diseases in humans, representing 2 of the 17 neglected diseases prioritised by the World Health Organisation. However, little is known about the role of urban animals in transmission of both parasite species., Findings: A sensitive non-invasive genetic method was used to monitor E. granulosus and E. multilocularis infection among dog faecal samples collected from an urban area in Estonia in 2012-13. Out of 181 dog faecal samples analysed, 2.2% tested positive for E. granulosus, determined by sequencing as genotype G1. None of the samples tested positive for E. multilocularis., Conclusions: We report contamination of an urban environment with highly pathogenic E. granulosus G1 disseminated by dogs, and a potential risk to human health.

Three groups of neonates were observed during their first 5 days of postnatal life. Healthy term babies (N = 22) did not differ in their heart rate variability (HRV) nor heart rate (HR) from the healthy preterm babies (N = 21) during the first 3 days. On day 5 beat-to-beat variability of term babies was greater. In healthy term and preterm infants HRV increased between days 1 and 3. HRV of the babies with respiratory distress syndrome (RDS) (N = 1) remained low throughout the study period. HR of the babies with RDS was significantly higher compared to the other groups on the days 1 and 3. Transcutaneous PO2 was high in healthy preterm infants compared to the other groups. The correlation between PaCO2 and PtcO2 in RDS was insufficient to make clinical judgement. PtcCO2 of all neonates tended to rise on the day 5 but the rise was most prominent in the infants with RDS. The correlation of PaCO2 and PtcCO2 was good. In RDS high HR, low HRV and elevated PtcCO2 were the typical findings and present throughout the study period.

The reactivity of the periodic heart rate variability (HRV) to the thermal vasomotor control was studied during quiet sleep in a total of 20 neonates which were classified in 5 groups according to their maturity. Thermal stimulation on the peripheral skin was applied by an air blower at the rates of 5, 2.5 and 1.5 cycles/min. The oscillation of successive R-R intervals of the ECG was determined by a hybrid computer technique during thermal stimulations and compared to spontaneous HRV activity. The indices of the HRV and the total power of the periodic HRV remained unchanged during thermal stimulations. The response of the periodic HRV was selective at the spectral band corresponding to the frequency of stimulation. It was maximal at 5 cycles/min. The relative response was highly significant (P less than 0.001) and it increased with increasing maturity. The state of SGA (small for gestational age) seemed to decrease the vasomotor response of the HRV. The results suggested that the thermal vasomotor control was functional already in small preterm infants and it tended to increase with increasing maturity as does the autonomic cardiac control in general.

The heart rate (HR), heart rate variation (HRV) and the power spectrum of the HR were studied in 1 to 10-week-old neonatal lambs. The average HR was highest and the indices of the HRV were lowest at the age of 1 to 3 weeks. However, there was a decreasing trend in the overall HRV with advancing age when it was normalized in relation to the average HR. The absolute beat-to-beat HRV increased after the age of 3 weeks; it remained the same when normalized in relation to the HR. The overall HRV was highest during waking and active sleep; it was lowest during quiet sleep. The beat-to-beat HRV was lower during quiet sleep than during active sleep. Three major peaks of HRV power were detected in the spectra of all lambs. During active sleep the HRV power increased at all frequencies ranging from 0 to 1.0 Hz. During waking the low-frequency HRV power was primarily increased. The high-frequency HRV was pronounced during quiet sleep and the state of sleepy waking, especially at the age of 4 to 6 weeks. Our study indicates that developmental factors and the sleep state have to be considered when HR patterns are experimentally investigated. Many similarities between the HR control of neonatal lambs and that of human neonates make it feasible to study the mechanisms of clinical HRV patterns by lamb experiments.