Methanogenic Archaea and oral infections — ways to unravel the black box

Archaea, organisms that make up the third domain of cellular life are members of the human oral microflora. They are strikingly less diverse than oral bacteria and appear to be relatively rare with respect to their numerical abundance. Since they have been exclusively found in association with oral infections such as periodontitis and apical periodontitis and given their unique physiology and energy metabolism, it is highly plausible that they are more than just secondary colonizers of infected areas, but instead are actively involved in the overall poly-microbial infection process. Conversely, it is a highly challenging task to clearly demonstrate their possible active participation – mostly due to the difficulty to grow them in routine microbiology laboratories. This current review points out the importance for understanding the medical impact of methanogens and aims at devising strategies for elucidating the true function of archaea in the oral ecosystem

Анализ применения криогелей для укрепления грунтов в условиях Крайнего Севера

Объектом исследования являются способы закрепления грунта. Цель работы - анализ применения криогеля для укрепления грунта. В магистерской диссертации рассмотрены прочностные характеристики криогелей. Рассмотрена технология применения криогеля для закрепления грунта. Проанализирована предварительно построенная компьютерная модель напряженно-деформированная состояния трубопровода при осадке грунта с применением криогеля и без него и сделаны выводы по перспективе применения криогеля.The object of the study ways of fixing of soil. The purpose of the study is to analyze the operational features and effectiveness of use of cryogel for soil strengthening. In the master thesis strength characteristics of cryogels are considered.The technology of use of cryogel for soil fixing is considered. Previously constructed computer model deformed conditions of the intense pipeline at soil draft with use of cryogel and without him is analysed and conclusions on the prospect of use of cryogel are drawn

Mentoring in students' adaptation to labor market requirements

The article contains the analyzes of the problems of youth employment, the development of mentoring in Russia. The ways of their joint decision are proposed with the purpose of acquiring production experience, professional self-realization and increasing the competitiveness of future specialists

Comparative analysis of the human saliva microbiome from different climate zones: Alaska, Germany, and Africa

Background: Although the importance of the human oral microbiome for health and disease is increasingly recognized, variation in the composition of the oral microbiome across different climates and geographic regions is largely unexplored. Results: Here we analyze the saliva microbiome from native Alaskans (76 individuals from 4 populations), Germans (10 individuals from 1 population), and Africans (66 individuals from 3 populations) based on next-generation sequencing of partial 16S rRNA gene sequences. After quality filtering, a total of 67,916 analyzed sequences resulted in 5,592 OTUs (defined at ≥97% identity) and 123 genera. The three human groups differed significantly by the degree of diversity between and within individuals (e.g. beta diversity: Africans > Alaskans > Germans; alpha diversity: Germans > Alaskans > Africans). UniFrac, network, ANOSIM, and correlation analyses all indicated more similarities in the saliva microbiome of native Alaskans and Germans than between either group and Africans. The native Alaskans and Germans also had the highest number of shared bacterial interactions. At the level of shared OTUs, only limited support for a core microbiome shared across all three continental regions was provided, although partial correlation analysis did highlight interactions involving several pairs of genera as conserved across all human groups. Subsampling strategies for compensating for the unequal number of individuals per group or unequal sequence reads confirmed the above observations. Conclusion: Overall, this study illustrates the distinctiveness of the saliva microbiome of human groups living under very different climatic conditions