Биология

Cholera remains a global threat to public health. Even sporadic cases of importation of the infection cause significant socio-economic damage. In connection with the current situation, the development and improvement of modern safe chemical vaccines against cholera caused by V. cholerae O1 and O139 serogroups plays an important role in reducing the incidence, which is an important and promising direction of scientific research. 

Many modern selection technologies are based on the use of haploid plants as a starting material. The spontaneous frequency of haploid development is very low (0.01–0.1%). In this regard, the creation of plant forms with increased frequency of parthenogenesis is important. The collection of corn lines with an increased frequency of haploid plants in the progeny was created at the Department of Genetics of the Saratov State University. High costs are required for maintain of a plant collections in the field.

Characterization of the species composition of the dominant representatives of Protozoa in natural plague foci is important for the study of certain aspects of ecology and persistence mechanisms of Yersinia pestis. Determination of systematic belonging of amoebas isolated from the soils of the Gorno-Altai high-mountain plague focus in 2016 year was carried out by analyzing nucleotide sequences of ribosomal genes of these protozoans. The analyzed sequences of ribosomal genes were obtained by PCR with specific primers followed by sequencing of PCR products.

Many bacteria, in response to unfavourable environmental conditions, can synthesise polyesters of the polyhydroxyalkanoate (PHA) class. These biopolymers, accumulating intracellularly in the form of granules, help the bacteria to cope with negative environments and are utilised as reserve sources of carbon and energy. Rhizobacteria of the species Azospirillum brasilense synthesise a single type of PHA, poly-3-hydroxybutyrate (PHB), in response to stress factors.

Until this article in the Saratov Province special studies of fungivorous beetles fauna of Coleoptera was carried out. The collection material was conducted by the authors in the spring and summer of 2017 with fruiting bodies of different species of xylotrophic Basidiomycetes of the families Polyporaceae and Fomitopsidaceae on the territory of 4 districts of the Saratov Province (Voskresenskiy, Khvalynskiy, Saratovskiy, Engelskiy). As a result, on 4 species of xylotrophic fungi were found 13 species of Coleoptera from 6 families.

Oculomotor activity is a necessary component of the human mental processes, thanks to which the acquisition, transformation and use of visual information takes place. Therefore, by registering and analyzing eye movements, we are able to access the hidden (internal) forms of activity that occur extremely quickly and unconsciously. Thanks to the appearance in Russia of modern trainees, interest in the oculomotor theme has now increased significantly.

Microorganisms inhabiting saline environments can produce compounds unique in structure and properties. This ability recently prompted researchers to study the biotechnological potential of halophiles. This work aimed at screening the exopolysaccharideproducing halophilic and halotolerant microorganisms of two saline lakes, one in in Egypt and the other in Russia. For strain isolation and characterization, we used microbiological and physico-chemical methods, as well as light and transmission electron microscopy.

Traumatic brain injury (TBI) is a major health problem that causes long term neurological deficit in the majority of patients and does not have any clinically proved effective treatment. Transcranial direct current stimulation (tDCS) is an emerging electroceutical therapy suggested for TBI rehabilitation. However, optimal parameters of stimulation and mechanisms of action are not determined due to lack of preclinical studies, impeding its clinical implementation.

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.

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.