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Suppressing the spontaneous emission in quantum emitters ensembles (atoms) is one of the topical problems in quantum optics and quantum technology. While many approaches are based on utilizing the subradiance effect in ordered quantum emitters arrays, the ensemble configurations providing the minimal spontaneous emission rate are yet unknown. In this work, we employ the differential evolution algorithm to identify the optimal configurations of a few atomic ensembles that support quantum states with maximal radiative lifetime. We demonstrate that atoms tend to assemble mostly in quasi-regular structures with specific geometry, which strongly depends on the minimally allowed interatomic distance r min . While the discovered specific non-radiative realizations of small ensembles cannot be immediately predicted, there is particular correspondence to the non-radiative states in the atomic lattices. In particular, we have found that states inheriting their properties either from the bound states in the continuum or band edge states of infinite lattices dominate across a wide range of r min values. Additionally, we show that for small interatomic distances, the linear arrays with modulated spacing have the smallest radiative losses exponentially decreasing as the size of the ensemble increases. [ABSTRACT FROM AUTHOR]

Chromatin insulators are special regulatory elements involved in modulation of enhancer-promoter interactions. The best studied insulators in Drosophila require Suppressor of Hairy Wing [Su(Hw)], Modifier of mdg4 [Mod(mdg4)] and centrosomal 190 kDa (CP190) proteins to be functional. These insulator proteins are colocalized in nuclear speckles named insulator bodies. Here, we demonstrate that post-translational modification of insulator proteins by small ubiquitin-like modifier (SUMO) and intact CP190 protein is crucial for insulator body formation. Inactivation of SUMO binding sites in Mod(mdg4)-67.2 leads to the inability of the mutant protein and Su(Hw) to be assembled into insulator bodies. In vivo functional tests show that a smaller amount of intact Mod(mdg4)-67.2, compared with the mutant protein, is required to restore the normal activity of the Su(Hw) insulator. However, high expression of mutant Mod(mdg4)-67.2 completely rescues the insulator activity, indicating that sumoylation is not necessary for enhancer blocking. These results suggest that insulator bodies function as a depot of sumoylated proteins that are involved in insulation and can facilitate insulator complex formation, but are nonessential for insulator action. [ABSTRACT FROM AUTHOR]

Little is known about the extent of glaciers and dynamics of the landscape in south-eastern Russian Altai. The effects of climate-induced fluctuations of the glaciers and the upper treeline of the Mongun-Taiga mountain massif were, therefore, reconstructed on the basis of in-situ, multiannual observations, geomorphic mapping, radiocarbon and surface exposure dating, relative dating (such as Schmidt-hammer and weathering rind) techniques and palaeoclimate-modelling. During the maximal advance of the glaciers, their area was 26-times larger than now and the equilibrium line of altitude (ELA) was about 800 m lower. Assuming that the maximum glacier extent took place during MIS 4, then the average summer temperatures were 2.7 °C cooler than today and the amount of precipitation 2.1 times higher. Buried wood trunks by a glacier gave ages between 60 and 28 cal ka BP and were found 600–700 m higher than the present upper treeline. This evidences a distinctly elevated treeline during MIS 3a and c. With a correction for tectonics we reconstructed the summer warming to have been between 2.1 and 3.0 °C. During MIS 3c, the glaciated area was reduced to less than 0.5 km 2 with an increase of the ELA of 310–470 m higher than today. Due to higher precipitation, the glaciated area during MIS 3a was close to the current ELA. Exposure dating ( 10 Be) would indicate that the maximum glacier extension was 24 ka BP, but the results are questionable. From a geomorphic point of view, the maximum extent can more likely be ascribed to the MIS4 stage. We estimate a cooling of summer temperature of – 3.8 to – 4.2 °C and a decrease in precipitation of 37–46% compared to the present-day situation. Samples of wood having an age of 10.6–6.2 cal ka BP were found about 350 m higher than the present treeline. It seems that the summer temperature was 2.0–2.5 °C higher and annual precipitation was double that of the present-day. For that period, the reconstructed glaciation area was 1 km 2 less than today. Three neoglacial glacier advances were detected. The glaciers covered about double the area during the Little Ice Age (LIA), summer cooling was 1.3 °C with 70% of the present-day precipitation. The reconstructed amplitude of climatic changes and the shift of the altitudinal zones show that the landscape has reacted sensitively to environmental changes and that dramatic changes may occur in the near future. [ABSTRACT FROM AUTHOR]

New hybrid materials based on Ag nanoparticles stabilized by a polyaminopropylalkoxysiloxane hyperbranched polymer matrix were prepared. The Ag nanoparticles were synthesized in 2-propanol by metal vapor synthesis (MVS) and incorporated into the polymer matrix using metal-containing organosol. MVS is based on the interaction of extremely reactive atomic metals formed by evaporation in high vacuum (10−4–10−5 Torr) with organic substances during their co-condensation on the cooled walls of a reaction vessel. Polyaminopropylsiloxanes with hyperbranched molecular architectures were obtained in the process of heterofunctional polycondensation of the corresponding AB2-type monosodiumoxoorganodialkoxysilanes derived from the commercially available aminopropyltrialkoxysilanes. The nanocomposites were characterized using transmission (TEM) and scanning (SEM) electron microscopy, X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (PXRD) and Fourier-transform infrared spectroscopy (FTIR). TEM images show that Ag nanoparticles stabilized in the polymer matrix have an average size of 5.3 nm. In the Ag-containing composite, the metal nanoparticles have a "core-shell" structure, in which the "core" and "shell" represent the M0 and Mδ+ states, respectively. Nanocomposites based on silver nanoparticles stabilized with amine-containing polyorganosiloxane polymers showed antimicrobial activity against Bacillus subtilis and Escherichia coli. [ABSTRACT FROM AUTHOR]

Background: Behavioral and psychological symptoms of dementia (BPSD) are a common problem among patients with dementia. This problem is usually treated by drugs, but they have limited efficacy and often cause adverse effects. Aromatherapy is a nonpharmacologic treatment that is simple to use and devoid of significant adverse effects. Objectives: To review the literature on the effectiveness of aromatherapy treatment in patients with BPSD. Design: A descriptive analysis of randomized clinical trials (RCTs) published in the English-language literature and cited in PubMed. Results: Eleven articles on RCTs were found, of which 1 had fewer than 10 participants, 2 were mistakenly presented as RCTs, and another did not report treatment for BPSD. In all, 7 articles with 417 participants total (range, 15-114) were reviewed. The mean age in all studies was greater than 69 years (range, 69-85 years), and the percentage of women was 55% (range, 50%-57%). The intervention period ranged from 10 days to 12 weeks. Two studies used Melissa oil and 5 others used lavender oil. The studies described different methods of administration for the oils, including spraying and rubbing over various body organs. The duration of treatment differed among the studies. In 3 studies the investigators concluded that the treatment was not effective and in 3 that it was effective; in 1 study no clear conclusion could be drawn. Conclusions: The difference between positive and negative studies was not explained by differences in the study population, the type of oil, or the duration of treatment. The significant difference apparently stems from the method of administration. When the oil was applied close to the olfactory system the outcome was positive. A study should be designed to assess the effect of the site of application of aromatherapy. [ABSTRACT FROM AUTHOR]

Several fragments (front and back protective glasses) of a solar array were investigated after its return from the orbital station Mir to Earth in 1998 after functioning in the low-Earth-orbit environment for 10.5 years. Three methods of surface analysis were applied: scanning electron microscopy, local x-ray microanalysis, and x-ray photoelectron spectroscopy. The main changes to solar array surfaces after prolonged exposition in low Earth orbit are caused by contamination layers (thicknesses up to 3 µ m) that deposit from the intrinsic outer atmosphere of the station. Besides contamination deposits, some surface damages are observed (dimensions of 5-20 µ m), caused by micrometeoroid and/or debris impacts. The outer layers of the contamination deposits consist of spheroid particles with dimensions of 0.3-0.5 µ m. The main components of the deposits are carbon (three chemical forms were observed by x-ray photoelectron spectroscopy) and silicon (two chemical forms: silicon dioxide and linear organosilicon). A silicon carbide presence is possible. [ABSTRACT FROM AUTHOR]

In the present study, we report the synthesis of a series of copper(II) complexes with a wide range of ligands and their testing in the copper catalyzed Chan‐Evans‐Lam (CEL) coupling of aniline and phenylboronic acid. The efficiency of the coupling was directly connected with the ease of the reduction of Cu(II) to Cu(I) of the complexes. The most efficient catalyst was derived from 4‐t‐butyl‐2,5‐bis[(quinolinylimino)methyl]phenolate and two Cu(II) ions. Depending on the counter‐anion nature and the concentration of the reaction mixture, the reaction can be directed to predominant C−N‐bond formation. Forty‐three derivatives of diphenylamine were prepared under the optimized conditions. The proposed mechanism of the catalysis was based on the reduction potential of a series of complexes, molecular weight measurements of the catalytic complex in MeOH and the kinetic studies of aniline and phenylboronic acid coupling. In addition, an 1H NMR experiment in a sealed NMR tube, without external oxygen supply available, proved that no complete Cu(II) to Cu(I) conversion was observed under the condition, ruling out the usually accepted mechanism of the C−N coupling, which included the oxygenation of the intermediately formed Cu(I) complexes after the key step of C−N conversion had already been completed. Instead, a mechanism was proposed, involving an oxygen molecule coordinated to two copper ions in the key C−N bond formation without any detectable conversion of the Cu(II) complexes to Cu(I). [ABSTRACT FROM AUTHOR]

Au/Al2O3 and Ni/Al2O3 prepared by deposition-precipitation and impregnation methods, respectively, and Au–Ni/Al2O3 prepared by impregnation of the Au/Al2O3 system with nickel have been studied by physicochemical methods. The catalysts were tested in allylbenzene isomerization at 443 K. The isomerization on Au/Al2O3 proceeds with a rather low rate, while monometallic Ni/Al2O3 is inactive. Unlike monometallic catalysts, Au–Ni/Al2O3 demonstrates a strong synergetic effect: the isomerization rate on the bimetallic sample exceeds the sum of the rates over the individual metals by an order of magnitude. The catalysts structure was estimated by XPS, DRIFT, and XAS techniques. It was revealed that nickel in Au–Ni/Al2O3 and Ni/Al2O3 exist as Ni2+ cations with the coordination state close to that in the precursor, gold in Au/Al2O3 exist as Au0 nanoclusters, whereas the Au0 nanoclusters co-exist with Au3+ cations in the bimetallic Au–Ni/Al2O3 sample. Reasons of the synergetic catalytic effect for Au–Ni/Al2O3 are discussed in terms of the formation of new positively charged Au catalytic centers. [ABSTRACT FROM AUTHOR]

The data on climate and vegetation of the Altai highland depressions are mapped in this paper. Investigations were conducted in June-July 2018 within the Bertek depression (the Ukok Plateau) and the Khindiktig-Khol' area that are decided to be the study objects. Also, the meteorological data of Bertek and Mugur-Aksy (about 40 km east to Khindiktig-Khol' Lake) were applied. The study was financially supported by Russian Foundation for Basic Research (RFBR) (Grant №18-05-00860 А). During the investigations, the standard meteorological researches were carried out, using the automatic weather station HOBO and albedo survey. What is more, the detailed characteristics of vegetation cover were compiled. The steppe (Poa attenuata, Helictotrichon hookeri, Festuca lenensis) and tundra patterns (Betula rotundifolia, Dryas oxyodonta, Kobresia myosuroides) are typical of Khindiktig-Khol' area. In some cases, the intarsia of two communities is founded. The steppe vegetation (Festuca kryloviana, Poa attenuata, Ptilagrostis mongolica) is predominant in the Bertek depression, whereas the tundra patterns are insignificant. Vegetation cover of the depressions develops under the conditions of short-term vegetation period and undergoes the negative impact of low summer temperatures. The mean July temperatures of the described depressions (Bertek – +9.3°С; Khindiktig-Khol' – +10.8°С) are lower than the average values of the plain steppe/forest-steppe (the mean July temperature of forest-steppe is from +18°С and higher). Moreover, the July temperatures of the studied areas are lower than in the forest-tundra of North Eurasia (from +12 – +13°С and higher). Due to the low summer temperatures the trees cannot grow in the Bertek and Khindiktig-Khol' areas. Hence, the depressions should have resembled the tundra landscape zone with the mean July temperature +7.5 – +12°С. However, the continuous cover of tundra cenoses is impossible due to the arid climate. We estimated the Vysotskii-Ivanov's precipitation-evaporation coefficient (K) (ratio of annual precipitation to annual evaporation). The K-coefficient of Khindiktig-Khol' equals 0.74, whereas in Bertek – 0.61. These values are lower that the K-coefficient of North European tundra (>1.5). Microclimatic observations of the neighboring areas with the different tundra and steppe cenoses show that the species, which are forming tundra with the dwarf birch (Betula rotundifolia), have unique features, thus creating favorable conditions for the existence of this com-munity. Comparing to the steppe area, the air during the daylight heats better not only above the tundra pattern, but also beneath it. Moreover, the dwarf birch (Betula rotundifolia) keeps the snow cover, which results in a better soil humidification and a reduction in seasonal freezing. Consequently, these factors result in diverse vegetation cover and appearance of exclusive tundra and steppe mixture in Khindiktig-Khol' depression. [ABSTRACT FROM AUTHOR]