Century-long Dynamics of Meadow Steppes in the Privolzhskaya Uplands

Information on the structure and dynamics of the zonal Central Russian meadow steppes is presented in terms of the example of the Privolzhskaya forest-steppe state nature reserve (Penza region, Russia). The cenotic diversity of the herbaceous vegetation of the reserve is represented by 91 associations, of which 48 referto steppes and 43 to steppe meadows. It has been revealed that the vegetation of the studied placer sites under the influence of an absolutely reserved regime undergoes mesophyticization and silvatization, which are more intensively manifested in the forest-steppe landscapes of the secondary moraine plains (areas of thePoperechenskaya steppe and Ostrovtsovskaya forest-steppe reserve) than in the eroded denudational plains of forest-steppe landscapes (areas of the Kuncherovskaya steppe and Ostrovtsovskaya forest-steppe reserves). The study of the dynamics of zonal meadow steppes in the Volga Uplands testifies to the inevitability of theirtransformation in modern climatic conditions into meadow, shrubby and even forest communities. Keywords: forest-steppe, meadow steppes, structure, dynamics, succession, reserve, geobotanical mapping, protection of steppe vegetatio

Alien Species in the Flora of the Middle Volga Region

The article presents information on the diversity and structure of the alien flora of the Middle Volga region on the border between the steppe and forest-steppe zones of the European botanical and geographical province. In the studied area, we identified 440 alien species of plants (24.6% of the total floristic diversity), including 59 invasive and potentially invasive species, the dispersal of which has already caused environmental consequences or could become a threat in the future. According to the degree of naturalization, alien plant species among the regional flora are represented by 146 ephemerophytes (33.2%), 122 colonophytes (27.7%), 151 epecophytes (34.3%) and 21 agriophytes (4.8%). As verified via the main method of skidding, alien species are distributed almost equally – 228 xenophytes (51.8%) and 212 ergasiophygophytes (48.2%). It was revealed that of the 150 species of alien plants, there are only 84 of the most common European species in the Middle Volga region, most of which do not show high cenotic activity. The obtained results actualize the development of a system of ecological and economic assessment of the consequences of introducing alien plant species into regional flora. Keywords: alien plants, invasive species, Middle Volga region, regional flor

The effect of humic substances on test-objects

The complex study of a number of humic substances was conducted with help of bioassay methods using invertebrates (Daphnia, paramecium, earthworms), terrestrial (wheat seeds) and aquatic plants (elodea, duckweed) and algae (Scenedesmus quadricauda). The ranges of concentrations of humates that have a negative and a stimulating effect on biological objects were identified. The efficiency of biological testing methods to evaluate the effect of humic substances on biological objects is shown

An international collaborative evaluation of central serous chorioretinopathy: different therapeutic approaches and review of literature. The European Vitreoretinal Society central serous chorioretinopathy study

Purpose: To study and compare the efficacy of different therapeutic options for the treatment of central serous chorioretinopathy (CSCR). Methods: This is a nonrandomized, international multicentre study on 1719 patients (1861 eyes) diagnosed with CSCR, from 63 centres (24 countries). Reported data included different methods of treatment and both results of diagnostic examinations [fluorescein angiography and/or optical coherent tomography (OCT)] and best-corrected visual acuity (BCVA) before and after therapy. The duration of observation had a mean of 11 months but was extended in a minority of cases up to 7 years. The aim of this study is to evaluate the efficacy of the different therapeutic options of CSCR in terms of both visual (BCVA) and anatomic (OCT) improvement. Results: One thousand seven hundred nineteen patients (1861 eyes) diagnosed with CSCR were included. Treatments performed were nonsteroidal anti-inflammatory eye drops, laser photocoagulation, micropulse diode laser photocoagulation, photodynamic therapy (PDT; Standard PDT, Reduced-dose PDT, Reduced-fluence PDT), intravitreal (IVT) antivascular endothelial growth factor injection (VEGF), observation and other treatments. The list of the OTHERS included both combinations of the main proposed treatments or a variety of other treatments such as eplerenone, spironolactone, acetazolamide, beta-blockers, anti-anxiety drugs, aspirin, folic acid, methotrexate, statins, vitis vinifera extract medication and pars plana vitrectomy. The majority of the patients were men with a prevalence of 77%. The odds ratio (OR) showed a partial or complete resolution of fluid on OCT with any treatment as compared with observation. In univariate analysis, the anatomical result (improvement in subretinal fluid using OCT at 1 month) was favoured by age <60 years (p < 0.005), no previous observation (p < 0.0002), duration less than 3 months (p < 0.0001), absence of CSCR in the fellow eye (p = 0.04), leakage outside of the arcade (p = 0.05) and fluid height >500 \u3bcm (p = 0.03). The OR for obtaining partial or complete resolution showed that anti-VEGF and eyedrops were not statistically significant; whereas PDT (8.5), thermal laser (11.3) and micropulse laser (8.9) lead to better anatomical results with less variability. In univariate analysis, the functional result at 1 month was favoured by first episode (p = 0.04), height of subretinal fluid >500 \u3bcm (p < 0.0001) and short duration of observation (p = 0.02). Finally, there was no statistically significant difference among the treatments at 12 months. Conclusion: Spontaneous resolution has been described in a high percentage of patients. Laser (micropulse and thermal) and PDT seem to lead to significant early anatomical improvement; however, there is little change beyond the first month of treatment. The real visual benefit needs further clarification

DISTRIBUTION OF THE PLANT SPECIES ON THE BORDER OF AREA IN THE MIDDLE VOLGA REGION

Summary. In the flora of Middle Volga region are revealed 518 species of vascular plants which are on borders of the continuous distribution. The characteristic of their distribution on physiographic provinces is provided. Distribution of vascular plant species in the Middle Volga region allows us to trace of zonal differences of the flora of Predvolzhye and Zavolzhye Forest-steppe from Zavolzhye Steppe, to more fully characterize the native biota of the forest-steppe ecotone and indicates the boundary position of region on the border of Pribalto-Volgo-Dneprovskii (Volgo-Donskoi area) and Vostochnyi (Zavolzhskii area) districts of European Botanical and Geographical province.Исследование выполнено при финансовой поддержке РФФИ в рамках проекта № 16-44-630414р_а

Comparative assessment of toxic effects of surfactants using biotesting methods

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.This study assesses the comparative sensitivity and possibility of obtaining fast results of various methods of biotesting for several surfactants: Tween 85, sodium dodecyl sulfate (SDS), Fairy dishwashing gel, and Mif washing powder. The following test organisms are used for the study: luminescent bacteria Photobacterium phosphoreum (Beijerinck), preparation of Ecolum luminescent bacteria, unicellular algae Scenedesmus quadricauda (G.M. Smith), infusorian Paramecium caudatum (Ehrenberg), and crustacean Daphnia magna (Straus). It has been revealed that Fairy dishwashing gel possesses the strongest toxicity against the studied test objects. Daphnia and algae are most sensitive to the effects of Fairy and SDS, protozoan and luminescent bacteria are most sensitive to SDS, and Ecolum is most sensitive to Mif washing powder. The tested aquatic organisms and Ecolum are most tolerant to the effect of Tween 85

Comparative assessment of toxic effects of surfactants using biotesting methods

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.This study assesses the comparative sensitivity and possibility of obtaining fast results of various methods of biotesting for several surfactants: Tween 85, sodium dodecyl sulfate (SDS), Fairy dishwashing gel, and Mif washing powder. The following test organisms are used for the study: luminescent bacteria Photobacterium phosphoreum (Beijerinck), preparation of Ecolum luminescent bacteria, unicellular algae Scenedesmus quadricauda (G.M. Smith), infusorian Paramecium caudatum (Ehrenberg), and crustacean Daphnia magna (Straus). It has been revealed that Fairy dishwashing gel possesses the strongest toxicity against the studied test objects. Daphnia and algae are most sensitive to the effects of Fairy and SDS, protozoan and luminescent bacteria are most sensitive to SDS, and Ecolum is most sensitive to Mif washing powder. The tested aquatic organisms and Ecolum are most tolerant to the effect of Tween 85