Variation of the Epiphytic Lichen Diversity in a Gradient of Atmospheric Pollution: Do Taxonomic, Genetic, and Functional Distances between Species Add any Information? GENERAL BIOLOGY

22 Studying the influence of reduced biological diver sity on functioning and stability of ecosystems is one of the priorities of modern ecology If the distances between species are important for biodiversity assessment, then strong perturbations that disturb ecosystem equilibrium should lead to signifi cant differences between the indices of diversity and disparity. In this study, we aimed to test this hypothesis using the epiphytic lichen communities, which are extremely sensitive to atmospheric pollution of the biotic component

Classical Simulation of Relativistic Quantum Mechanics in Periodic Optical Structures

Spatial and/or temporal propagation of light waves in periodic optical structures offers a rather unique possibility to realize in a purely classical setting the optical analogues of a wide variety of quantum phenomena rooted in relativistic wave equations. In this work a brief overview of a few optical analogues of relativistic quantum phenomena, based on either spatial light transport in engineered photonic lattices or on temporal pulse propagation in Bragg grating structures, is presented. Examples include spatial and temporal photonic analogues of the Zitterbewegung of a relativistic electron, Klein tunneling, vacuum decay and pair-production, the Dirac oscillator, the relativistic Kronig-Penney model, and optical realizations of non-Hermitian extensions of relativistic wave equations.Comment: review article (invited), 14 pages, 7 figures, 105 reference

BioBull3_02VorobeichikLO

Abstract -Contamination of the southern taiga forests (Middle Urals) by from cooper smelters (heavy metals combined with SO 2 ) not only decreases the mean rate of decomposition of pure cellulose, but also radically changes the spatial structure of the destruction process. Heterogeneity of distribution of the destruction rate is sharply increased near the source of emission due to differentiation of the space into microsites with high and low destruction rates. The range of spatial heterogeneity amounts to several tens of centimeters and the distribution of microsites with a high rate is random within several tens of meters. A hypothesis has been put forward that the described changes in the spatial structure of the destruction process are related, above all, to disturbed colonization of the substrate by soil microfungi. ECOLOG

Ecol6_07VorobeichikLO

Abstract -Spatial variation in the cellulolytic activity of the soil microflora during the growing season (from May to September) has been studied in spruce-fir forests exposed to emissions from the Middle Ural CopperSmelting Plant. It has been shown that the average rate of decomposition of pure cellulose in polluted areas is significantly reduced, with its spatial variation being markedly increased. The spatial pattern of cellulolytic activity remains stable during the growing season, and the integrated parameters of frequency distributions in zones with different pollution levels change with time in the same direction

Epiphytic Lichenosynusia under Conditions of Chemical Pollution: Dose-Effect Dependencies

Abstract -The dose-effect dependencies, which characterize response of the epiphytic lichenosynusia of southern taiga in the Middle Urals to pollution by discharges of a copper-smelting plant, are substantially nonlinear and, in most cases, have an S-shaped form. A transition from background to impact state is very sharp and begins when the background level of pollution is exceeded by 1.5 -2.3 times .. Epiphytic lichens are traditionally used as a subject for ecological monitoring and bioindicators of chemical pollution of the environment Most studies on using lichens as bioindicators were performed on the territory of cities and large industrial agglomerations. Natural habitats were much rarer. In the former case, the works include sufficiently big samples, making it possible to map the territory in detail. In the latter case, insufficient segmentation along the gradient of pollution (only "experiment," "control," and several intermediate sample areas) is a common defect. Such a scheme allows us to determine only general trends of changes and their range. Moreover, many important problems have not been considered. One of these problems is construction of the dose-effect dependencies, in which the amount of toxicants penetrating into an ecosystem is regarded as a dose, and parameters of condition of the lichenosynusia is an effect. These dependencies are necessary to understand how the lichen cover behaves under the stress of unfavorable factors and to determine the limits of stability of the lichens. In addition, the anthropogenic maximum tolerance load can be estimated by means of these dependencies. Many years ago, ecologists realized the importance of the dose-effect dependencies, which might be analogous with the dose curves (a basic element of classical toxicology) at the level of community and ecosystem THE REGION UNDER STUDY Our study was performed on the western slope of the Middle Urals in the southern taiga subzone. The discharges of a copper-smelting plant affected the studied area. By the time of our investigation, the plant had been functioning for 50 years. The following substances are the main pollutants: S0 2 and heavy metals (Cu, Pb, Cd, Zn, As, etc.). In previous work

The structure of spruce-fir tree stands mortality under impact of the Middle Ural copper smelter emissions

The influence of industrial pollution on mortality values (dead fallen wood and dead standing trees) and its distribution by degrees of decomposition were investigated in spruce-fir forest stands in the vicinity of the Middle Ural copper smelter (the city of Revda, Sverdlovsk region). The total mortality and mortality in each size category did not depend on the distance to the source of pollution. At the same time, the amount of dead fallen wood was significantly greater (1.9 times) in the polluted area (2 and 4 km from the smelter) as compared with the background territory (30 km from the smelter). Mortality proportion out of the total number of the trees (both live and dead) did not differ significantly between the sites, although this parameter tended to increase nearer the smelter. The distribution of mortality by size categories revealed significant differences between background territory and site with average level of contamination, as well as background territory and highly contaminated site. Observed differences are associated with an increased proportion of lesser mortality near the smelter (by 15 % and 12 % as compared with areas of background and middle levels of contamination, respectively), as well as because of double-declining of medium- and large-sized mortality near the smelter. The distribution of the living tree stands by size categories also has a connection with level of contamination. The average diameters of the living tree stand and the elements of coarse woody debris (dead fallen wood and dead standing trees) do not differ significantly between sites with different levels of contamination. For the small-sized dead fallen wood, the proportion of weakly decomposed stems increased with the level of pollution, while proportion of strongly decomposed stems decreased. The distribution of medium- and large-sized dead fallen wood on the stages of decomposition does not vary between sites with different levels of pollution

Dexamethasone Is Superior to Dexmedetomidine as a Perineural Adjunct for Supraclavicular Brachial Plexus Block: Systematic Review and Indirect Meta-analysis.

Both dexamethasone and dexmedetomidine are effective peripheral nerve block (PNB) perineural adjuncts that prolong block duration. However, each is associated with side effects. With paucity of head-to-head comparisons of these adjuncts, the question of the best adjunct to mix with local anesthetics (LA) for PNB is unanswered. This meta-analysis aims to inform current practice and future research by identifying the superior adjunct by comparing dexamethasone and dexmedetomidine. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, trials comparing the combination of perineural dexamethasone or dexmedetomidine with LA to LA alone for PNB were sought. The Cochrane Risk of Bias Tool was used to assess the methodological quality of trials, and indirect or network meta-analyses using random-effects modeling were planned. We designated duration of analgesia as a primary outcome. Secondary outcomes included sensory and motor block durations, sensory and motor block onset times, and the risks of hypotension, sedation, and neurological symptoms. Fifty trials were identified, including only 1 direct comparison, precluding a network meta-analysis. Indirect meta-analysis of 49 trials (3019 patients) was performed. Compared to dexmedetomidine, dexamethasone prolonged the duration of analgesia by a mean difference (95% confidence interval [CI]) of 148 minutes (37-259 minutes) (P = .003), without prolonging sensory/motor blockade. Dexmedetomidine increased rates of hypotension (risk ratio [95% CI], 6.3 [1.5-27.5]; P = .01) and sedation (risk ratio [95% CI], 15.8 [3.9-64.6]; P = .0001). Overall risk of bias was moderate, and publication bias was noted, resulting in downgrading evidence strength. There is low-quality evidence that both adjuncts similarly prolong sensory/motor blockade. However, dexamethasone may be a superior adjunct; it improves the duration of analgesia by a statistically significant increase, albeit clinically modest, equivalent to 2.5 hours more than dexmedetomidine, without the risks of hypotension or sedation. Future direct comparisons are encouraged

Of changes of forest litter respiration in gradients of industrial pollution

The effect of industrial pollution on the total CO2 emission from the soil surface and the forest litter (measured in situ) in the areas of impact of Middle Ural Copper Smelter (spruce-fir forests) and Karabash Copper Smelter (birch forests) has been studied. Measurements were carried out in the middle of the 2011–2013 growing seasons at 60 plots. Contamination has little influence on the overall CO2 emissions (the difference between the background and impact areas is 1.5– 1.8 times, a significant decrease was observed only at the industrial barren) and has almost no effect on the emission from the forest litter. At the same time, the specific respiratory activity of the litter (respiration of a unit mass of substrate) is closely related to the level of pollution, and the difference between the impact and background areas is substantially greater (3.5–15 times). Comparison of the litter contribution to the total emission of CO2 (30–60 % in coniferous forests, and 17–32 % in hardwood) and the root reserve (7–10 % and 2–5 %, respectively) allows to interpret respiration of litter as being mainly microbial. Stability of carbon dioxide fluxes from the forest litter in a gradient of pollution is due to the interaction of two countervailing processes: reduction of specific respiratory activity of forest litter (due to the inhibition of microorganisms inhabiting it) and the increase of its reserve