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Daridorexant is a dual orexin receptor antagonist in clinical development for the treatment of insomnia. Breast-cancer resistant protein (BCRP) is an efflux pump expressed in intestinal epithelium and hepatocytes, contributing to the absorption, distribution, and elimination of drugs and endogenous compounds. In vitro, daridorexant inhibits BCRP with an IC50 of 3.0 μmol/L. The BCRP substrate rosuvastatin is a cholesterol-lowering drug, recommended for clinical drug-drug interaction (DDI) studies. In order to exclude an inhibitory effect of daridorexant on BCRP, this single-centre, open-label, two-treatment Phase 1 study investigated the effect of daridorexant at steady state on the pharmacokinetics (PK) of single-dose rosuvastatin in 20 healthy male subjects. In addition, safety and tolerability were assessed. A single oral dose of 10 mg rosuvastatin on Day 1 was followed by 96 hours observation. Thereafter, 25 mg daridorexant was administered once daily (o.d.) on Days 5-8 and in combination with 10 mg rosuvastatin on Day 8. On Days 9-12, subjects received 25 mg daridorexant alone. PK sampling was performed up to 120 hours after treatment administration. The results showed that concomitant administration of 25 mg daridorexant o.d. at steady state did not affect the exposure parameters of rosuvastatin in a relevant way, as indicated by the ratios of geometric means (GMRs) ([rosuvastatin + daridorexant]/[rosuvastatin alone]) of 0.93 for both Cmax and AUC0-∞ . Administration of a single dose of 10 mg rosuvastatin, multiple doses of 25 mg daridorexant alone or in combination were well tolerated. Taken together, daridorexant and BCRP substrates can be safely co-administered.

There is a significant lack of binary stars with RR Lyrae components. In this brief contribution, we introduce 20 new candidates in the Galactic bulge identified on the basis of the Light-Travel-Time Effect with expected orbital periods between 3 and 15 years.

Metal nanocones can exhibit several strong plasmonic resonances, which are associated with intense and accessible electromagnetic hot spots. They can thus be used to enhance light–matter interactions or to facilitate location-specific sensing while enabling separation of some non-specific contributions towards the sensing signal. Nanocones and similar 3D structures are often fabricated with the use of the so-called self-shading effect, which occurs during the evaporation of a metal film into circular nanowells. Unfortunately, a full description of a successful deposition process with all the essential details is currently missing in literature. Here we present a detailed view of the fabrication of ordered arrays of conical gold nanostructures using electron beam lithography and gold electron beam evaporation. We show that the symmetry of the fabricated nanostructures is influenced by the lateral position of the substrate on the sample holder during the deposition. Off-axis deposition or tilt of the sample leads to asymmetric nanostructures. When the deposited film is thick enough, or the nanowells narrow enough, the entrance aperture is clogged, and nanocones with sharp tips are formed. In contrast, flat-top truncated cones are produced for thinner films or wider nanowells. All these findings help to identify inherent limits for the production of wafer-scale arrays of such non-planar nanostructures. On the other hand, they also suggest new fabrication possibilities for more complicated structures such as mutually connected nanocones for electrically addressable chips.

We present 20 newly discovered candidates for binary systems with an RR~Lyrae companion. Using the photometric data from the Optical Gravitational Lensing Experiment (OGLE) and Korea Microlensing Telescope Network (KMTNet) for the Galactic bulge, we searched for binary candidates among non-modulated fundamental-mode RR~Lyrae variables. We constructed and investigated over 9000 $O-C$ diagrams for individual pulsators, in order to find signs of the light-travel time effect. We found 20 variables exhibiting cyclic variation in the $O-C$ (time of the observed minus calculated brightness maximum) diagram, which can be associated with a second component in the system, but for confirmation of binarity, a long-term radial velocity study is necessary. The modeling of the $O-C$ diagrams yields orbital parameters, estimates of the semi-amplitude of the radial velocity curve, and the mass function. The orbital periods of our candidates range from 3 to 15 years. Two of the binary candidates display a minimum mass higher than the assumed mass of the RR~Lyrae component, which points towards an evolved companion that can under some circumstances contribute significantly to the total light of the system., Comment: 7 pages, 3 figures, Accepted for publication in MNRAS

The early-type massive binary MQ Cen (P$_{orb}$=3.7 d) has been investigated by means of high-resolution ($R\sim48\,000$) spectral analysis and multi-band (Johnson $BVRI$ and Str\"{o}mgren $vby$) light curve modeling. The physical parameters of the components have been found to be $M_1= 4.26\pm0.10$ M$_{\odot}$, $R_1= 3.72\pm0.05 $R$_{\odot}$, $T_{\rm eff1}=16\,600\pm520$ K, and $M_2= 5.14\pm0.09 $M$_{\odot}$, $R_2= 7.32\pm0.03 $R$_{\odot}$, $T_{\rm eff2}=15\,000\pm500$ K for the primary and secondary, respectively. The orbital inclination is $i=87.0\pm0.2$ deg. The distance to MQ Cen has been derived to be $d=2\,460\pm310$ pc which locates it in the Crux OB1 association. However, the age of MQ~Cen ($\sim70$ Myr) is higher than the one reported for the Crux OB1 association ($\sim$6 Myr). The derived masses are implying a spectral type of B5 for the primary and B4 for the secondary component. Nevertheless, the secondary component, which is more massive, appears to be cooler than the primary component: It has completed its lifetime on the main-sequence and it is now positioned at the turn-off point of the giant branch, meanwhile the less massive primary component is still staying on the main-sequence., Comment: 14 pages, 7 figures and 4 tables, accepted for publication in Astrophysics and Space Science

Background The benefit of probiotics in newborn children in relation to allergy and general morbidity later in life appears to be controversial. Allergic diseases represent an increasingly important health problem worldwide in recent years. This is evident in all age groups. The occurrence of allergic illnesses also continues to rise exponentially, and thus the use of preventive and prognostic methods, particularly in children with an inherently higher risk of allergy, is gaining increased importance. Since the advent of probiotics the effect of probiosis on immunity through alterations of composition and function of the human gut microbiome has been increasingly studied. The exact mechanisms have not yet been clearly defined. The Academy of Sciences of the Czech Republic (The Czech Academy of Sciences has suggested that the expression of TH1 and TH2 cytokines in umbilical blood is associated with an increased risk of allergies. The counter -balance of Th1 and Th2 affect Immunoglobulin E (IgE) production and maturation of the gastrointestinal tract epithelium. Case presentation We examined IgE levels in 3000 samples of umbilical blood taken from children born into families with a positive history of allergy in one or both parents from 2007 to 2017. At the age of ten days, those with high IgE were given Colinfant Newborn (a lyophilized non-pathogenic strain of Escherichia.coli) for one month, three times weekly. At 15 months and three years we investigated the levels of Immunoglobulins E,A and G, and the incidence of illness and allergy. The results revealed that allergy and high umbilical IgE is strongly linked with family history (p ≤ 0.001). We also detected differences in seasonality, especially with regards to pollen allergies. Eighty percent of children treated with Colinfant Newborn had significantly reduced IgE and morbidity at 13–15 months and 3 years, and furthermore without any clinical signs of allergy. Normalization of Immunoglobulins A and G was seen in 90% of treated subjects (p ≤ 0.001). These levels significantly correlated with an almost negligible morbidity up to 4 years of life. Colinfant Newborn, a lyophilized strain of Esherichia coli (E. coli), and a normal component of intestinal flora, readily colonizes the intestinal tract. It’s long term presence significantly stimulates the production of specific and non-specific intestinal antibodies. and optimalizes immune development through tolerance. In our study Colinfant Newborn reduced the incidence of infections later in life by safely and effectively normalizing immunoglobulin levels in the majority of treated patients. Conclusion Our study strongly suggests as positive effect of physiological Escherichia coli on the microbiome of newborn children as evidenced by a significantly reduced incidence of allergy and morbidity when applied early in life. These benefits appear to be strongly strain specific.

The star phi Dra comprises a spectroscopic binary and a third star that together form a visual triple system. It is one of the brightest chemically peculiar (CP) stars of the upper main sequence. Despite these facts, no comprehensive study of its multiplicity has been performed yet. In this work, we present a detailed analysis of the triple system based on available measurements. We use radial velocities taken from four sources in the literature in a re-analysis of the inner spectroscopic binary (Aab). An incorrect value of the orbital period of the inner system Aab about 27 days was accepted in literature more than forty years. A new solution of orbit with the 128-day period was determined. Relative position measurements of the outer visual binary system (AB) from Washington Double Star Catalog were compared with known orbital models. Furthermore, it was shown that astrometric motion in system AB is well described by the model of Andrade (2005) with a 308-year orbital period. Parameters of A and B components were utilized to estimate individual brightness for all components and their masses from evolutionary tracks. Although we found several facts which support the gravitational bond between them, unbound solution cannot be fully excluded yet.

Malicek, J., Bouda, F., Liska, J., Palice, Z. & Peksa, O. 2015. Contribution to the lichen biota of the Romanian Carpathians. — Herzogia 28: 713–735. We present floristic data from 82 localities mainly from eight mountain ranges of the Romanian Carpathians (Fagaras, Parâng, Cindrel, Harghita, Hasmas, Bihor, Maramures and Rodna). The main habitats investigated were subalpine and alpine communities, beech and spruce forests, and limestone areas at lower altitudes. During four field expeditions, 364 lichenized and three lichenicolous fungi were recorded. Thirty-seven taxa are new for Romania. Biatora subduplex, Helocarpon pulverulum, Lecanora filamentosa, L. flavoleprosa, Lecidea huxariensis, Leucocarpia biatorella, Myriospora dilatata, Pertusaria borealis, Placynthium dolichoterum, Reichlingia leopoldii, Rhizocarpon carpaticum and Vezdaea stipitata are new for southeastern Europe. Lecanora flowersiana is reported for the first time from Europe. Candelariella commutata, Cetrelia chicitae, Lecanora ...

We present a comprehensive study of Z CVn, an RR Lyrae star that shows long-term cyclic variations of its pulsation period. A possible explanation suggested from the shape of the O-C diagram is the light travel-time effect, which we thoroughly examine. We used original photometric and spectroscopic measurements and investigated the period evolution using available maximum times spanning more than one century. If the binary hypothesis is valid, Z CVn orbits around a black hole with minimal mass of $56.5$ $\mathfrak{M}_{\odot}$ on a very wide ($P_{\rm orbit}=78.3$ years) and eccentric orbit ($e=0.63$). We discuss the probability of a formation of a black hole-RR Lyrae pair and, although we found it possible, there is no observational evidence of the black hole in the direction to Z CVn. However, the main objection against the binary hypothesis is the comparison of the systemic radial velocity curve model and spectroscopic observations that clearly show that Z CVn cannot be bound in such a binary. Therefore, the variations of pulsation period are likely intrinsic to the star. This finding represents a discovery/confirmation of a new type of cyclic period changes in RR Lyrae stars. By the analysis of our photometric data, we found that the Blazhko modulation with period of 22.931 d is strongly dominant in amplitude. The strength of the phase modulation varies and is currently almost undetectable. We also estimated photometric physical parameters of Z CVn and investigated their variations during the Blazhko cycle using the Inverse Baade-Wesselink method., 15 pages, 8 tables, 9 figures, accepted for publication in MNRAS

The a-index samples the flux of the 5200 Å region by comparing the flux at the center with the adjacent regions. The final intrinsic peculiarity index Δa was defined as the difference between the individual a-values and the a-values of normal stars of the same colour (spectral type). Here we present, for the first time, a case study to detect and analyse Asymptotic Giant Branch (AGB) stars in the Magellanic Clouds. For this, we use our photometric survey of the Magellanic Clouds within the a-index. We find that AGB stars can be easily detected on the basis of their Δa index in an efficient way.

Vondrak, J. & Liska, J. 2013. Lichens and lichenicolous fungi from the Retezat Mts and overlooked records for the checklist of Romanian lichens. — Herzogia 26: 293–305. Records of 223 taxa of lichens, lichenicolous fungi and non-lichenized but lichen-like fungi are reported from the Retezat Mts, south-western Romania. The list includes 44 taxa new to Romania: Absconditella pauxilla, Acarospora heppii, Agonimia gelatinosa, Agonimia tristicula, Anaptychia bryorum, Arthrorhaphis grisea, Bacidia illudens, Biatoridium monasteriense, Buellia uberior, Caloplaca arenaria, C. cerinelloides, C. chrysodeta, C. magni-filii, C. saxifragarum, C. tiroliensis, C. velana var. schaereri, C. xanthostigmoidea, Candelariella aggregata s. l., C. antennaria, Chaenotheca xyloxena, Dacampia hookeri, Dactylospora urceolata, Epilichen scabrosus, Fellhanera subtilis, Frutidella pullata, Gyalecta geoica, Illosporium carneum, Lecanora cavicola, Leptogium teretiusculum, Lichenoconium lecanorae, Lichenomphalia umbellifera, Mac...

The article explains the current structure of Körber's herbarium, located in the Nationaal Herbarium Nederland, Leiden (L). Originally, Körber's herbarium was composed of two separate collections. One part, Koerber Typenherbar, represents well-developed samples of each species, but they are in fact often fragments of specimens from the main collection (Koerber Stammherbar). Several examples are presented which demonstrate the relationship between both parts of the collection, various origins of specimens in the Koerber Typenherbar and their importance for lectotypification. Some specimens in Körber's herbarium were labelled only with an abbreviation or a symbol instead of a locality. All abbreviations/symbols with their explanations, kept in the Leiden herbarium archive, are listed here with information on the current names of the sampling localities in Poland and the Czech Republic.

Abdominal pain-related functional gastrointestinal disorders in children include functional dyspepsia, functional abdominal pain, irritable bowel syndrome, and abdominal migraine. We aimed to evaluate a possible association between functional abdominal pain disorders and Helicobacter pylori infection and faecal calprotectin level.Prospective observational study including consecutive children with functional gastrointestinal disorders fulfilling Rome III criteria (cases) and age/sex-matched healthy controls. H pylori has been detected by biopsy-based tests and stool-antigen detection, faecal calprotectin by enzyme-linked immunosorbent assay.A total of 56 cases (27 with functional dyspepsia) and 56 controls were enrolled. H pylori being detected in 17 of 56 cases (30.4%) and 4 of 56 controls (7.1%, odds ratio: 5.7; 95% confidence interval [CI]: 1.8-18.2, P = 0.003). H pylori was detected significantly more frequently in cases with functional dyspepsia (14/27, 51.9% odds ratio: 14.0; 95% CI: 3.9-49.7, P = 0.00001) than in controls and not in cases with other well-recognized functional gastrointestinal complaints (3/29, 10.3%). The median faecal calprotectin level was similar in cases (7.8 μg/g, 95% CI: 7.8-8.4) including those with gastritis, and controls (9.1 μg/g, 95% CI: 7.8-11.3). Gastritis features were more frequent in H pylori-infected and noninfected cases with functional dyspepsia (27/27, 100%) than in cases with other abdominal functional complaints (15/29, 51.7%, P = 0.007).H pylori gastritis and noninfectious gastritis were associated with functional dyspepsia in children referred for abdominal pain-related functional gastrointestinal disorders while faecal calprotectin is not a predictor of gastritis and is similar in children with functional abdominal pain symptoms and in controls.

The distribution and ecology of four threatened lichens in the Czech Republic, Evernia mesomorpha, Hyperphyscia adglutinata, Hypotrachyna revoluta and Parmotrema perlatum, have been studied. All species are mainly epiphytic, but recent records from the Czech Republic are largely from siliceous rocks in river/brook valleys. Changes in distribution and substrate preferences are documented and discussed.

Context: Multiple stellar systems are unique laboratories for astrophysics. Analysis of their orbital dynamics may reveal invaluable information about the physical properties of the participating stars. Unfortunately, there are only a few known and well described multiple systems, this is even more so for systems located outside the Milky Way galaxy. A particularly interesting situation occurs when the inner binary in a compact triple system is eclipsing. This is because the stellar interaction, typically resulting in precession of orbital planes, may be observable as a variation of depth of the eclipses on a long timescale. Aims: We aim to present a novel method to determine compact triples using publicly available photometric data from large surveys. Here we apply it to eclipsing binaries (EBs) in Magellanic Clouds from OGLE III database. Methods: We analyzed light curves (LCs) of 26121 LMC and 6138 SMC EBs with the goal to identify those for which the orbital inclination varies in time. Archival LCs of the selected systems, when complemented by our own observations with Danish 1.54m telescope, were thoroughly analyzed using the PHOEBE program. Time dependence of the EB's inclination was described using the theory of orbital-plane precession. By observing the parameter-dependence of the precession rate, we were able to constrain the third companion mass and its orbital period around EB. Results: We identified 58 candidates of new compact triples in Magellanic Clouds. This is the largest published sample of such systems so far. Eight of them were analyzed thoroughly and physical parameters of inner binary were determined together with an estimation of basic characteristics of the third star. These data may provide important clues about stellar formation mechanisms for objects with different metalicity than found in our galactic neighborhood., Accepted for publication in Astronomy and Astrophysics

The study aimed to determine how the response of the epiphytic lichen vegetation to sulphur air pollution is affected by interaction with other factors (distance from pollution sources, habitat, altitude, initial eutrophication of the tree bark). It was based on a series of four successive recordings taken over a period of 18 years with increasing pollution levels and on the same set of 139 solitary trees. Relationships between habitat variables and lichen community composition are assessed using canonical correspondence analysis. The data set comprised 69 lichen species. Ordination of initial species composition on trees revealed two major gradients: eutrophication and acidity.The species composition significantly changed with time, with a general decrease of the total number of lichen species per tree. In general, species sensitive to air pollution decreased, while tolerant species increased in number. Change over time differed depending on the position of the tree within the landscape (relative to one major source of pollution, the town of Tábor, whereas the distance to the other source, Sezimovo Ústí, was not significant) and on the initial species composition found on the tree. Trees under the effect of eutrophication changed their species composition less, indicating that the effect of eutrophication (mainly increased bark pH) may ameliorate the effects of air pollution; a local effect of eutrophication also seems to play an important role. Distance to pollution sources had only a small impact on the rate of change and perhaps other local conditions (sheltered or humid position, altitude) play a role in this interaction. There was a decrease of the overall heterogeneity of the data set over time. This means that the gradients in species composition attributable to these variables became less important over time. Therefore, one of the effects of air pollution is also a general homogenization of the lichen vegetation of the solitary trees.

We investigate in detail the LiTE of the most probable binary candidate TU UMa. We used a new code applied on previously available and newly determined maxima timings to confirm binarity and refine parameters of the orbit of the RRab component in the binary system. The binary hypothesis is also tested using RV measurements. We used new approach to determine brightness maxima timings based on template fitting. This can also be used on sparse or scattered data. This approach was successfully applied on measurements from different sources. To determine the orbital parameters of the double star TU UMa, we developed a new code to analyse LiTE that also includes secular variation in the pulsation period. Its usability was successfully tested on CL Aur, an eclipsing binary with mass-transfer in a triple system that shows similar changes in the O-C diagram. Since orbital motion would cause systematic shifts in mean RVs (dominated by pulsations), we computed and compared our model with centre-of-mass velocities. They were determined using high-quality templates of RV curves of RRab stars. Maxima timings adopted from the GEOS database (168) together with those newly determined from sky surveys and new measurements (85) were used to construct an O-C diagram spanning almost five proposed orbital cycles. This data set is three times larger than data sets used by previous authors. Modelling of the O-C dependence resulted in 23.3-year orbital period, which translates into a minimum mass of the second component of about 0.33 M_s. Secular changes in the pulsation period of TU UMa over the whole O-C diagram were satisfactorily approximated by a parabolic trend with a rate of -2.2 ms/yr. To confirm binarity, we used RV measurements from nine independent sources. Although our results are convincing, additional long-term monitoring is necessary to unambiguously confirm the binarity of TU UMa., Comment: 14 pages, 11 figures, Accepted for publication in Astronomy & Astrophysics

Context: The presence of heavier chemical elements in stellar atmospheres influences the spectral energy distribution (SED) of stars. An uneven surface distribution of these elements, together with flux redistribution and stellar rotation, are commonly believed to be the primary causes of the variability of chemically peculiar (CP) stars. Aims: We aim to model the photometric variability of the CP star PHI Dra based on the assumption of inhomogeneous surface distribution of heavier elements and compare it to the observed variability of the star. We also intend to identify the processes that contribute most significantly to its photometric variability. Methods: We use a grid of TLUSTY model atmospheres and the SYNSPEC code to model the radiative flux emerging from the individual surface elements of PHI Dra with different chemical compositions. We integrate the emerging flux over the visible surface of the star at different phases throughout the entire rotational period to synthesise theoretical light curves of the star in several spectral bands. Results: The synthetic light curves in the visible and in the near-UV regions are in very good agreement with the observed variability of the star. The lack of usable far-UV measurements of the star precludes making any conclusions about the correctness of our model in this spectral region. We also obtained 194 new BVRI observations of PHI Dra and improved its rotational period to P=1.716500(2). Conclusions: We show that the inhomogeneous distribution of elements, flux redistribution, and rotation of the star are fully capable of explaining the stellar variability in the visible and the near-UV regions. The flux redistribution is mainly caused by bound--free transitions of silicon and bound--bound transitions of iron.

This paper presents an extensive overview of known and proposed RR Lyrae stars in binaries. The aim is to revise and extend the list with new Galactic field systems. We utilized maxima timings for eleven RRab type stars with suspicious behaviour from the GEOS database, and determined maxima timings from data of sky surveys and our own observations. This significantly extended the number of suitable maxima timings. We modelled the proposed Light Time Effect (LiTE) in O-C diagrams to determine orbital parameters for these systems. In contrast to recent studies, our analysis focused on decades-long periods instead of periods in the order of years. Secondary components were found to be predominantly low-mass objects. However, for RZ Cet and AT Ser the mass of the suspected companion of more than one solar mass suggests that it is a massive white dwarf, a neutron star or even a black hole. We found that the semi-major axes of the proposed orbits are between 1 and 20 au. Because the studied stars belong to the closest RR Lyraes, maximal angular distances between components during orbit should at least be between 1 and 13 mas and this improves the chance to detect both stars using current telescopes. However, our interpretation of the O-C diagrams as a consequence of the LiTE should be considered as preliminary without reliable spectroscopic measurements. On the other hand our models give a prediction of the period and radial velocity evolution which should be sufficient for plausible proof of binarity., Comment: accepted for publication in MNRAS, 18 pages, 18 figures

To compile a proposal of the system of taking complex prenatal, perinatal and postnatal care of pregnant women and their children in the Czech Republic with taking into account medical and salutogenic approaches.A questionnaire was prepared comprising questions for mothers and making it possible to exactly use specified data from their healthcare documentation. The method thus consisted of a secondary data analysis and subsequent contact with mothers. This was implemented in the form a qualitative and narrative interview. The study included 541 women from five Czech regions.In this group, there was a high level of the preventive care with persisting preference of prenatal consulting rooms conducted by physicians. Most deliveries occurred in institutions in the presence of physicians. In the groups evaluated, there were, however, no significant differences. In spite of this, the evaluation of delivering women indicated that there is a high level of the perinatal care in terms of the medical approach. However, the salutogenic care calls for increasing the active participation of midwives in the prenatal, perinatal and postnatal care and extension and intensification of activities particularly in the psychosocial area.In the group monitored, there were no significant correlations of determined perinatal interventions with the method and result of the delivery and condition of the mother and newborn. It is to mention that the medical perinatal care is at a high level.

To compile a proposal of the system of taking complex prenatal, perinatal and postnatal care of pregnant immigrants in the Czech Republic with taking into account medical and salutogenic approaches.The research was implemented by the form of a controlled interview and was based on a questionnaire comprising 50 questions focused on the evaluation of taking the prenatal, natal and postnatal care of immigrants. The data were accumulated among immigrants from Vietnam, Mongolia and Ukraine.It is possible to conclusively state that no principal dissatisfaction with taking care of pregnant women in the Czech Republic compared to native countries was demonstrated. There is a difference in a more considerable participation of midwives in the prenatal and natal care compared to the native countries. Failures in taking care of mothers-immigrants in the Czech Republic are considered to be the poor communication, particularly in association with the language barrier, limited possibilities of the participation of family members in the delivery and persisting unsuitable behaviour of certain healthcare professionals.In the Czech Republic, the medical care is at a higher level compared to native countries. For the improvement of the salutogenic attitude, it is necessary to take into consideration certain results and provide their application to practice.

Aims: The Danish 1.54-meter telescope at the La Silla observatory was used for photometric monitoring of selected eccentric eclipsing binaries located in the Small Magellanic Cloud. The new times of minima were derived for these systems, which are needed for accurate determination of the apsidal motion. Moreover, many new times of minima were derived from the photometric databases OGLE and MACHO. Eighteen early-type eccentric-orbit eclipsing binaries were studied. Methods: Their (O-C) diagrams of minima timings were analysed and the parameters of the apsidal motion were obtained. The light curves of these eighteen binaries were analysed using the program PHOEBE, giving the light curve parameters. For several systems the additional third light also was detected. Results: We derived for the first time and significantly improved the relatively short periods of apsidal motion from 19 to 142 years for these systems. The relativistic effects are weak, up to 10% of the total apsidal motion rate. For one system (OGLE-SMC-ECL-0888), the third-body hypothesis was also presented, which agrees with high value of the third light for this system detected during the light curve solution., Comment: 8 pages, 5 figures, 4 tables, plus the appendix data tables with times of minima. Published in 2014A&A...572A..71Z

We investigated 1234 fundamental mode RR Lyrae stars observed by the All Sky Automated Survey (ASAS) to identify the Blazhko (BL) effect. A sample of 1547 BL stars from the literature was collected to compare the modulation-period distribution with stars newly identified in our sample. A classical frequency spectra analysis was performed using Period04 software. Data points from each star from the ASAS database were analysed individually to avoid confusion with artificial peaks and aliases. Statistical methods were used in the investigation of the modulation-period distribution. Altogether we identified 87 BL stars (48 new detections), 7 candidate stars, and 22 stars showing long-term period variations. The distribution of modulation periods of newly identified BL stars corresponds well to the distribution of modulation periods of stars located in the Galactic field, Galactic bulge, Large Magellanic Cloud, and globular cluster M5 collected from the literature. As a very important by-product of this comparison, we found that pulsation periods of BL stars follow Gaussian distribution with the mean period of $0.54\pm0.07$ d, while the modulation periods show log-normal distribution with centre at $\log(P_{\rm m}~{\rm [d]})=1.78\pm0.30$ dex. This means that 99.7 % of all known modulated stars have BL periods between 7.6 and 478 days. We discuss the identification of long modulation periods and show, that a significant percentage of stars showing long-term period variations could be classified as BL stars., Comment: 13 pages, 9 figures, Accepted for publication in Astronomy & Astrophysics

New physical elements of the early B-type eclipsing binary V346 Cen are derived using the HARPS spectra downloaded from the ESO archive and also numerous photometric observations from various sources. A model of the observed times of primary and secondary minima that fits them best is a combination of the apsidal motion and an abrupt decrease in the orbital period from 6322123 to 6321843 (shortening by 24 s), which occurred somewhere around JD 2 439 000. Assumption of a secularly decreasing orbital period provides a significantly worse fit. Local times of minima and the final solution of the light curve were obtained with the program PHOEBE. Radial velocities of both binary components, free of line blending, were derived via 2D cross-correlation with a program built on the principles of the program TODCOR. The oxygen lines in the secondary spectra are weaker than those in the model spectra of solar chemical composition. Using the component spectra disentangled with the program KOREL, we find that both components rotate considerably faster than would correspond to the synchronization at periastron. The apside rotation known from earlier studies is confirmed and compared to the theoretical value.

We present our joint efforts to study variable stars in open clusters. This includes a new catalogue, a photometric survey for new variables, and the database WEBDA. Our tools will shed more light on stellar variability in open clusters.

Eclipsing binaries (EBs) are a key which opens the door to a chamber of knowledge. Thus the research of EBs in open clusters (OCs) is very promising. However, only several lists of eclipsing binaries known in OCs have been published, the last one almost three decades ago. We introduce a new catalogue of EBs in the field of open clusters. In addition we establish a new program for skilled amateur astronomers who are able to produce a significant amount of photometric data of sufficient accuracy. Photometry as well as spectroscopy of selected EBs in OCs will be used to determine stellar parameters of components in binaries and cluster parameters.

The preliminary results of a study of a neglected, relatively bright, short-periodic (P=0.48 d), near contact eclipsing binary BS Vulpeculae is given. We present our new complete (BVRI) light curves, and physical parameters of the system based on them, derived by the 2003 version of the Wilson–Van Hamme code.

We present a detailed study of the close eclipsing binary BS Vulpeculae. Although it is relatively bright (V: 10.9-11.6 mag) and belongs to short-periodic variable stars (P = 0.48 days), it is rather neglected. To perform a thorough period analysis, we collected all available photometric observations that span the time interval of 1898-2010. Observations include archive photographic plate measurements and visually determined eclipse minima timings done in 1979-2003, which were later shown to be biased to accommodate the existing linear ephemeris. Applying our own direct period analysis we found a well-defined shortening of the orbital period of dP/dt = -6.70(17) x 10(-11) = -2.11(6) ms yr(-1), which implies a continual mass flow from the primary to the secondary component. Using the 2003 version of the Wilson-Van Hamme code, our new complete BV(IR)(C) light curves were analyzed and the physical parameters of the system were derived. We found that BS Vul is a near contact binary system with the primary component filling its critical Roche lobe. The luminosity enhancement on the left shoulder of the secondary minimum shown in the light curves can be explained as a result of a persistent hot spot on the secondary due to the mass transfer from the primary component to the secondary one and heating the facing hemisphere of the secondary component, which is consistent with our result of period analysis. With the period decrease, BS Vul will evolve toward the contact phase. It is another good observational example as predicted by the theory of thermal relaxation oscillations.

Reactions of 2α,3α-epoxide X, derived from 19β,28-epoxy-A(1)-nor-18α-oleanane, with acids proceed with migration of the 10β-methyl group into the position 2β, giving rise to unsaturated alcohols XII and XIV and diene IX. Reaction with boron trifluoride etherate afforded ketone XI in addition to XII and XIV. Olefin VIII rearranged in acidic medium to give olefins XXVI and XXVII. The rearranged products were converted into other derivatives and their structure was established by 1H and 13C NMR, IR, UV and mass spectra.

Metal nanocones can exhibit several strong plasmonic resonances, which are associated with intense and accessible electromagnetic hot spots. They can thus be used to enhance light–matter interactions or to facilitate location-specific sensing while enabling separation of some non-specific contributions towards the sensing signal. Nanocones and similar 3D structures are often fabricated with the use of the so-called self-shading effect, which occurs during the evaporation of a metal film into circular nanowells. Unfortunately, a full description of a successful deposition process with all the essential details is currently missing in literature. Here we present a detailed view of the fabrication of ordered arrays of conical gold nanostructures using electron beam lithography and gold electron beam evaporation. We show that the symmetry of the fabricated nanostructures is influenced by the lateral position of the substrate on the sample holder during the deposition. Off-axis deposition or tilt of the sample leads to asymmetric nanostructures. When the deposited film is thick enough, or the nanowells narrow enough, the entrance aperture is clogged, and nanocones with sharp tips are formed. In contrast, flat-top truncated cones are produced for thinner films or wider nanowells. All these findings help to identify inherent limits for the production of wafer-scale arrays of such non-planar nanostructures. On the other hand, they also suggest new fabrication possibilities for more complicated structures such as mutually connected nanocones for electrically addressable chips., This research was carried out under project GA17-33767L of Grant Agency of the Czech Republic, H2020 Twinning programme (project SINNCE, 810626) and Brno University of Technology (project FSI-S-17-4482). The work was also supported by the project CEITEC 2020 (LQ1601) with financial support from the Ministry of Education, Youth and Sports of the Czech Republic under the National Sustainability Programme II. We acknowledge CzechNanoLab Research Infrastructure supported by MEYS CR (LM2018110). The research was partly funded by the Austrian Science Fund (FWF) grant number I 3064 and by the City of Vienna Hochschuljubiläumsfonds project H-268476/2016.

Metal nanocones can exhibit several strong plasmonic resonances, which are associated with intense and accessible electromagnetic hot spots. They can thus be used to enhance light–matter interactions or to facilitate location-specific sensing while enabling separation of some non-specific contributions towards the sensing signal. Nanocones and similar 3D structures are often fabricated with the use of the so-called self-shading effect, which occurs during the evaporation of a metal film into circular nanowells. Unfortunately, a full description of a successful deposition process with all the essential details is currently missing in literature. Here we present a detailed view of the fabrication of ordered arrays of conical gold nanostructures using electron beam lithography and gold electron beam evaporation. We show that the symmetry of the fabricated nanostructures is influenced by the lateral position of the substrate on the sample holder during the deposition. Off-axis deposition or tilt of the sample leads to asymmetric nanostructures. When the deposited film is thick enough, or the nanowells narrow enough, the entrance aperture is clogged, and nanocones with sharp tips are formed. In contrast, flat-top truncated cones are produced for thinner films or wider nanowells. All these findings help to identify inherent limits for the production of wafer-scale arrays of such non-planar nanostructures. On the other hand, they also suggest new fabrication possibilities for more complicated structures such as mutually connected nanocones for electrically addressable chips.