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The resolution of the broad-scale tree of eukaryotes is constantly improving, but the evolutionary origin of several major groups remains unknown. Resolving the phylogenetic position of these “orphan” groups is important, especially those that originated early in evolution, because they represent missing evolutionary links between established groups. Telonemia is one such orphan taxon for which little is known. The group is composed of molecularly diverse biflagellated protists, often prevalent although not abundant in aquatic environments. Telonemia has been hypothesized to represent a deeply diverging eukaryotic phylum but no consensus exists as to where it is placed in the tree. Here, we established cultures and report the phylogenomic analyses of three new transcriptome data sets for divergent telonemid lineages. All our phylogenetic reconstructions, based on 248 genes and using site-heterogeneous mixture models, robustly resolve the evolutionary origin of Telonemia as sister to the Sar supergroup. This grouping remains well supported when as few as 60% of the genes are randomly subsampled, thus is not sensitive to the sets of genes used but requires a minimal alignment length to recover enough phylogenetic signal. Telonemia occupies a crucial position in the tree to examine the origin of Sar, one of the most lineage-rich eukaryote supergroups. We propose the moniker “TSAR” to accommodate this new mega-assemblage in the phylogeny of eukaryotes.

Extracellular vesicles (EVs) are membrane-enclosed vesicles which play important role for cell communication and physiology. EVs are found in many human biological fluids, including blood, breast milk, urine, cerebrospinal fluid (CSF), ejaculate, saliva etc. These nano-sized vesicles contain proteins, mRNAs, microRNAs, non-coding RNAs and lipids that are derived from producing cells. EVs deliver complex sets of biological information to recipient cells thereby modulating their behaviors by their molecular cargo. In this way EVs are involved in the pathological development and progression of many human disorders, including neurodegenerative diseases. In this study EVs purified by ultracentrifugation from CSF of patients with Parkinson's disease (PD) and individuals of the comparison group were characterized using nanoparticle tracking analysis, flow cytometry and cryo-electron microscopy. Vesicular size and the presence of exosomal marker CD9 on the surface provided evidence that most of the EVs were exosome-like vesicles. Cryo-electron microscopy allowed us to visualize a large spectrum of extracellular vesicles of various size and morphology with lipid bilayers and vesicular internal structures. Thus, we described the diversity and new characteristics of the vesicles from CSF suggesting that subpopulations of EVs with different and specific functions may exist.

The invention and development of next or second generation sequencing methods has resulted in a dramatic transformation of ancient DNA research and allowed shotgun sequencing of entire genomes from fossil specimens. However, although there are exceptions, most fossil specimens contain only low (~ 1% or less) percentages of endogenous DNA. The only skeletal element for which a systematically higher endogenous DNA content compared to other skeletal elements has been shown is the petrous part of the temporal bone. In this study we investigate whether (a) different parts of the petrous bone of archaeological human specimens give different percentages of endogenous DNA yields, (b) there are significant differences in average DNA read lengths, damage patterns and total DNA concentration, and (c) it is possible to obtain endogenous ancient DNA from petrous bones from hot environments. We carried out intra-petrous comparisons for ten petrous bones from specimens from Holocene archaeological contexts across Eurasia dated between 10,000-1,800 calibrated years before present (cal. BP). We obtained shotgun DNA sequences from three distinct areas within the petrous: a spongy part of trabecular bone (part A), the dense part of cortical bone encircling the osseous inner ear, or otic capsule (part B), and the dense part within the otic capsule (part C). Our results confirm that dense bone parts of the petrous bone can provide high endogenous aDNA yields and indicate that endogenous DNA fractions for part C can exceed those obtained for part B by up to 65-fold and those from part A by up to 177-fold, while total endogenous DNA concentrations are up to 126-fold and 109-fold higher for these comparisons. Our results also show that while endogenous yields from part C were lower than 1% for samples from hot (both arid and humid) parts, the DNA damage patterns indicate that at least some of the reads originate from ancient DNA molecules, potentially enabling ancient DNA analyses of samples from hot regions that are otherwise not amenable to ancient DNA analyses.

The COVID-19 pandemic has tremendously affected higher education systems in Russia and all over the world, forcing to transform curriculum into an online format, which is a challenge for all the educational process participants. The current study discusses the implementation of online learning amid the COVID-19 pandemic in the Russian higher education context and investigates the challenges experienced by university teachers during this period to define their readiness for online education. To address the above-mentioned issues, a study was conducted in Peter the Great St. Petersburg Polytechnic University. A variety of methods of scientific and pedagogical research were used including systematic structural analysis, synthesis, work with research papers, the generalization of experience and experimental work, observation, surveys, etc., with 87 university teachers asked to respond to several sets of questions describing their online teaching experience after the launch of online education amid the COVID-19 pandemic. The analysis of the participants’ answers helped to identify the following main challenges experienced by university teachers: computer literacy level, the university electronic environment and support, academic staff readiness and students’ readiness for online learning, the last two being the most important hindering the implementation of the efficient online education process. It was also underlined by most respondents that methodological work of a teacher in a digital educational environment differs from conventional teaching methods. Thus, psychological, technological, methodological support and teachers’ professional development programs are of vital importance to minimize the negative impact of the rapid changes of the educational process and to ensure efficient online education.

All his attention was focused on the study of archaeological sites and the purchase of objects from burial grounds, and he also conducted the first archaeological excavations of burial mounds in Russia. Part of his scientific library was bought by the Academy of Sciences, part was brought to Moscow University, but most of the materials and collections of the scientist was lost during the fire in the building of the Kunstkamera Museum in 1747. [...]currently there are only 8 original drawings of the scientist in the Archive of the Russian Academy of Sciences in Saint Petersburg; 6 of which were made by Messerschmidt himself and 2 presumably made by draftsman K. G. Schulmann. Messerschmidt himself became the first artist who captured the Okunev culture sites of the Bronze Age \"The Statue of Ulug Khurtuyakh Tas\" and \"The Statue of KhysTas\" in the 20s of the 18th century.

The project to bring together all the books of the world in Alexandria was not only intended to contribute to the glory of the Ptolemies, but also aimed to attract scholars to the city, who would be capable of exploiting these books to produce others and to thus advance the literature and science of their time. This book demonstrates that the availability and critical study of the 500,000 scrolls which the Library of Alexandria probably contained made possible the production of some remarkable pieces of Alexandrian literature and philosophy, the considerable increase in historical and geographical knowledge, as well as outstanding contributions to the history of mathematics, astronomy, mechanics, and medicine.The book recalls how Alexandria was founded and became the most beautiful city in the ancient world. It also recalls the incredible series of wars, popular revolts, assassinations, palace intrigues, and debaucheries that brought about the inexorable decline of this city and its Library.

We provide a general framework for the analysis of institutional dynamics in an environment in which payoffs and political powers change stochastically. Assuming that economic and political institutions as well as individual types can be ordered, and preferences and the distribution of political power satisfy natural “single-crossing” (increasing differences) conditions, we prove existence of a pure-strategy Markov voting equilibrium, provide conditions for its uniqueness, and present a number of comparative static results. We then use this framework to study the dynamics of political rights and repression in the presence of threats from extremist groups and the dynamics of collective experimentation.

The reforms of Russian Tsar Peter I (1682–1725) touched all spheres of life, including the Church. The purpose of this paper is to bring into focus his approach to the reform of monasticism. It reflects on Peter’s personal remarks as reported both by his Russian and his foreign interlocutors, his legislation, including law drafts, and practical measures such as the All-Joking, All-Drunken Synod. The principal conclusion is that it was this Russian ruler who was the first to call into question the very existence of monasticism and who came close to the ultimate dissolution of monasteries. He did not abolish monasticism not because it was a too radical step but because he devised measures of reform to raise its standards and improve its public utility. His treatment of the monastic tradition should be interpretated not as secularization but rather as modernization. Peter’s personal “monachophobia” is best understood as a modernizing impulse. His objective was the creation of a “modern” state whose Church and clergy represented contemporary values. Traditional, unreformed monasticism presented an obstacle in his progress towards this goal. The legacy of Peter’s policy was an increasing monachophobia in Russia apparent from the 18th century onwards.

The story of Russian imperialism has deep historical roots, and this book shows how Byzantium, the most powerful medieval and Christian empire, is repeatedly presented in Russian history as the source of the empire's imperial legitimacy.