Topological constraints on spiral wave dynamics in spherical geometries with inhomogeneous excitability

We analyze the way topological constraints and inhomogeneity in the excitability influence the dynamics of spiral waves on spheres and punctured spheres of excitable media. We generalize the definition of an index such that it characterizes not only each spiral but also each hole in punctured, oriented, compact, two-dimensional differentiable manifolds and show that the sum of the indices is conserved and zero. We also show that heterogeneity and geometry are responsible for the formation of various spiral wave attractors, in particular, pairs of spirals in which one spiral acts as a source and a second as a sink -- the latter similar to an antispiral. The results provide a basis for the analysis of the propagation of waves in heterogeneous excitable media in physical and biological systems.Comment: 5 pages, 6 Figures, major revisions, accepted for publication in Phys. Rev.

Ethnical and cultural particularity of gluttonic discourse

The article is devoted to ethnic perculiarity and originality of the Russian and British lingvocultures in line with gustative preference

Effect of El Niño on the mesosphere/lower thermosphere winds over Collm (51.3°N, 13°E)

Mesosphere/lower thermosphere (MLT) zonal winds measured by a VHF meteor radar at Collm, Germany (51.3°N, 13.0°E) during late winter 2015/2016 show very strong westerly winds above about 90 km, but not below that height. This anomaly appears during a very strong El Niño event. The comparison of Niño3 equatorial sea surface temperature index and the Collm MLT wind time series starting in 2004 shows that in January and especially in February zonal winds are positively correlated with the Niño3 index. The signal is strong for the upper altitudes (above 90 km) accessible to the radar observations, but weakens with decreasing height. This reflects the fact that during El Niño years the westerly winter middle atmosphere wind jet is weaker on an average, and this is also the case with the easterly lower thermospheric jet. The El Niño effect on the meridional wind is weak. The experimental results can be qualitatively reproduced by numerical experiments using the MUAM mechanistic global circulation model with prescribed tropospheric temperatures and latent heat release for El Niño and La Niña conditions.Der Zonalwind in der oberen Mesosphäre/unteren Thermosphäre über Collm (51.3°N, 13.0°E) in der zweiten Hälfte des Winter 2015/2016 weist eine besonders starke westliche Komponente oberhalb von etwa 90 km auf. Diese Anomalie erfolgte während eines sehr starken El Niño-Ereignisses. Der Vergleich von Collmer Zonalwinden seit 2004 und dem Niño3-index zeigt im Januar und besonders Februar eine positive Korrelation. Diese ist stark oberhalb von 90 km, nimmt aber nach unten hin ab. Dies spiegelt die Tatsache wider, dass während El Niño-Jahren im Mittel der stratosphärische/mesosphärische Westwindjet schwächer ist. Dieses Signal kehrt aber in der oberen Mesosphäre um, so dass der thermosphärische Ostwindjet ebenfalls schwächer ist. Der Effekt auf den meridionalen Wind ist schwächer. Die Beobachtungen können mit Modellexperimenten qualitativ reproduziert werden

El Niño influence on the mesosphere/lower thermosphere circulation at midlatitudes as seen by a VHF meteor radar at Collm (51.3 ° N, 13 ° E)

Mesosphere/lower thermosphere (MLT) zonal winds continuously measured by a VHF meteor radar at Collm, Germany (51.3° N, 13.0° E) in the height range 82 – 97 km from 2004 to date are analyzed with respect to the signature of El Niño. The comparison of Niño3 equatorial SST index and MLT wind time series shows that in January and especially in February zonal winds are positively correlated with the Niño3 index. We note a delay of about one month of the MLT zonal wind effect with respect to equatorial sea surface temperature variability. The signal is strong for the upper altitudes (above 90 km) accessible to the radar observations, but weakens with decreasing height. This reflects the fact that during El Niño years the westerly winter middle atmosphere wind jet is weaker, and this is also the case with the easterly lower thermospheric jet. Owing to the reversal of the absolute El Niño signal from negative to positive with altitude, at the height of the maximum meteor flux, which is around 90 km, the El Niño signal is weak. The experimental results can be qualitatively reproduced by numerical experiments using a mechanistic global circulation model with prescribed tropospheric temperatures and latent heat release for El Niño and La Niña conditions

Nanodiamond Theranostic for Light-Controlled Intracellular Heating and Nanoscale Temperature Sensing

[Image: see text] Temperature is an essential parameter in all biological systems, but information about the actual temperature in living cells is limited. Especially, in photothermal therapy, local intracellular temperature changes induce cell death but the local temperature gradients are not known. Highly sensitive nanothermometers would be required to measure and report local temperature changes independent of the intracellular environment, including pH or ions. Fluorescent nanodiamonds (ND) enable temperature sensing at the nanoscale independent of external conditions. Herein, we prepare ND nanothermometers coated with a nanogel shell and the photothermal agent indocyanine green serves as a heat generator and sensor. Upon irradiation, programmed cell death was induced in cancer cells with high spatial control. In parallel, the increase in local temperature was recorded by the ND nanothermometers. This approach represents a great step forward to record local temperature changes in different cellular environments inside cells and correlate these with thermal biology

Effects of enzymatically depolymerised fucoidan on effector functions of innate and adaptive immunity cells

The use of sulfated polysaccharides (fucoidans) as active pharmaceutical ingredients or adjuvants poses the challenge of obtaining structurally characterised and homogeneous samples or their oligomeric fractions maintaining high biological activity. The authors obtained a highly purified enzymatic hydrolysate of fucoidan from the brown alga Fucus evanescens and compared its biological activity with that of a native sample. The aim of the study was to compare, in vitro and in vivo, the effects of depolymerised fucoidan from the brown alga F. evanescens and native fucoidan on the effector functions of innate and adaptive immunity cells loaded with ovalbumin (OVA). Materials and methods: the effects of the fucoidan samples (depolymerised and native) on the expression of the main immunophenotypic markers by innate and adaptive immunity cells (neutrophils, monocytes, natural killers, and lymphocytes) were studied in vitro using flow cytometry. The levels of serum OVA-specific antibodies (IgG, IgG1, IgG2а) and cytokines (IFN-γ, IL-2, IL-10, IL-12) were studied in vivo using BALB/c mice immunised with OVA. The statistical analysis of the data obtained was performed using the Statistica 10 software package. Results: in vitro, both fucoidan samples altered the expression of the main immunophenotypic markers by innate and adaptive immunity cells, indicating their activation. In vivo, mice treated with the fucoidan samples demonstrated an increase in the levels of OVA-specific antibodies (IgG, IgG1 and IgG2a) and in the production of cytokines (IFN-γ, IL-2, IL-10). Conclusions: the effects of enzymatically depolymerised fucoidan on functional activity of innate and adaptive immunity cells are comparable to those of native fucoidan. The findings indicate the possibility of using enzymatic hydrolysis products of fucoidan as adjuvants for a wide range of prophylactic and therapeutic vaccines

Asthenia expression among medical universities students during internship

The article presents a study of the severity of asthenia among students of a medical university during industrial practice.В статье представлено исследование выраженности астении среди обучающихся медицинского университета во время производственной практики