Biology

Bacteria Fouling in the Systems of Technical and Circulating Water Supply of Balakovo Nuclear Power Station

The article is devoted to the study of bacteria in the system of technical water supply of Balakovo nuclear power plant (BNPP). The work was carried out in 2017. The samples were taken at the following sites: backup diesel generator of the 3rd unit (røde’s-3), pumping station of feeding pond-cooler (PSFPC), coastal pump station of unit 3 (CPS-U3), coastal pumping station of power unit № 4 (CPSP-U4), turbine hall of power unit № 3 (TH-PU3), turbine hall of power unit № 4 (TH-PU4).

Development of Fluorescent Glioma in Rats under Pharmacological Modulation of Beta2-Adrenergic Receptor

This study shows the role of adrenergic mechanisms in the development of fluorescent glioma in rats and the impairment of the blood-brain barrier (BBB) permeability. The results demonstrate that the progression of glioma was accompanied by a gradual increase in the BBB permeability and an increased expression of vascular beta2-adrenoreceptors (B2-AR). The pharmacological blockade of B2-AR reduced the degree of BBB disruption, the migration of cancer cells and increased the survival of animals.

The Effect of Pollutants on the Emergence of Rifampicin Resistance in Bacteria of the Pseudomonas Genus

The anthropogenic pressure on ecosystems may contribute to the spread of antibiotic resistance among bacteria in natural conditions. Due to this, the aim of this work was to study the impact of specific biocides, antibiotics, pesticides and heavy metals on the emergence of rifampicin resistant mutants of Pseudomonas putida. To assess the impact of toxic substances on the emergence of rifampicin-resistant mutants the studied substances and rifampicin in the final concentration of 100 μg/ml were added into nutrient medium before plating.

Lymphatic Meningeal Role in Processes of Brain Clearing: in vivo Visualization

In the experiments on rats, Evans Blue dye and gold nanorods were injected into the brain parenchyma, followed by visualization with optical coherent tomography and a fluorescent microscopy. The results showed that meningeal lymphatics play an important role in the brain clearing, using markers introduced into the tissues. It has been shown that the deep cervical lymph node is the first anatomical “station” for the outflow of fluid from the brain. The data obtained shed light on the lymphatic mechanisms underlying the drainage and clearing of brain functions.

Phenological Characteristics of Orthopterous Insects (Orthoptera) in the Volga-Kama State Nature Biosphere Reserve

In this brief communication, the results of the research on the seasonal dynamics of orthopterous insects (Orthoptera) are discussed. The research was performed in the Volga-Kama State Nature Biosphere Reserve. Field sampling and observations were carried out for different biotopes of the nature reserve. The phenological characteristics of 26 background species of the families Tettigonioidea, Tetrigidae, and Acridoidea were revealed. The species under study were divided into five phenological groups: spring-summer, early summer, summer summer-late summer, and late summer.

Optimization of Photodynamic Effects on Permeability of Cerebral Vessels

Photodynamic treatment (PDT) causes a significant increase in the permeability of the blood-brain barrier (BBB) in healthy mice. Using different doses of laser radiation (635 nm, 10–40 J/cm2 ) and photosensitizer (5-aminolevulinic acid – 5-ALA, i.v.), we found the optimal PDT for the reversible opening of the BBB, exhibiting brain tissue recovery 3 days after PDT. Further increases in the laser radiation or 5-ALA doses have no amplifying effect on the BBB permeability, but are associated with severe damage of brain tissues.

Epiphytic Lichens of Natural Park “Kumysnaya Polyana”

The article provides information about the epiphytic lichen flora of the Natural Park “Kumysnaya Polyana” (NP), which is located in Saratov. It is a regional SPNA (Special Protected Natural Area). The researches were conducted in forest communities of NP in 2011–2016. Standard techniques were used in the collection and identification of lichens. An index of species specificity of lichens for forophytes was calculated. An annotated list consists of 37 species and includes the information about their preferential forophytes.

Influence of the Cultivation Temperature on Morphometric and Functional Indices of Growth Triticum durum L.

The object of the study was sprouts of durum wheat Triticum durum L. Cultivation was carried out at a temperature of 15 ± 1°C and 20 ± 2°C. To study the influence of the temperature factor on the development of the photosynthetic apparatus, the quantitative content of chlorophyll a, chlorophyll b, and carotenoids was determined. Some varieties, when subjected to a change in the temperature of cultivation, respond with a change in the indices determining their stress tolerance, namely the ratio of chlorophyll a and chlorophyll b, carotenoids and chlorophylls.

The Functional State of Systemic Hemodynamics Russian and Foreign Students at Orthostasis

This work is devoted to the comparative analysis of the functional state of systemic hemodynamics in Russian and foreign students depending on the localization of the transition zone in the chest leads of ECG during the active orthostatic test. Having assessed physical development, we measured the parameters of arterial pressure and ECG using the module «Electrocardiogram» APK «Valenta». The prevalence of asthenic type of physique in foreign students against the deficiency of physical development determines the vertical position of the heart.

On the Contribution of Cell Aggregation and Extracellular DNA to Biofilm Formation and Stabilization in Azospirillum brasilense Bacteria

Little is known about the functions of the principal matrix components and about the role of cell surface structures in the formation and stabilization of Azospirillum biofilms. It is known that as compared with A. brasilense strain Sp245, its flhB1, fabG1, and mmsB1 mutants, defective in flagellar assembly, form biofilms less well. We made comparative study of bacterial aggregation, biofilm formation, and the effect of DNAase on biofilms.

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