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A central question in evolutionary biology is whether sponges or ctenophores (comb jellies) are the sister group to all other animals. These alternative phylogenetic hypotheses imply different scenarios for the evolution of complex neural systems and other animal-specific traits 1 – 6 . Conventional phylogenetic approaches based on morphological characters and increasingly extensive gene sequence collections have not been able to definitively answer this question 7 – 11 . Here we develop chromosome-scale gene linkage, also known as synteny, as a phylogenetic character for resolving this question 12 . We report new chromosome-scale genomes for a ctenophore and two marine sponges, and for three unicellular relatives of animals (a choanoflagellate, a filasterean amoeba and an ichthyosporean) that serve as outgroups for phylogenetic analysis. We find ancient syntenies that are conserved between animals and their close unicellular relatives. Ctenophores and unicellular eukaryotes share ancestral metazoan patterns, whereas sponges, bilaterians, and cnidarians share derived chromosomal rearrangements. Conserved syntenic characters unite sponges with bilaterians, cnidarians, and placozoans in a monophyletic clade to the exclusion of ctenophores, placing ctenophores as the sister group to all other animals. The patterns of synteny shared by sponges, bilaterians, and cnidarians are the result of rare and irreversible chromosome fusion-and-mixing events that provide robust and unambiguous phylogenetic support for the ctenophore-sister hypothesis. These findings provide a new framework for resolving deep, recalcitrant phylogenetic problems and have implications for our understanding of animal evolution. Deeply conserved syntenic characters unite sponges with bilaterians, cnidarians, and placozoans in a monophyletic clade to the exclusion of the comb jellies (ctenophores)—placing ctenophores as the sister group to all other animals.

Cephalopods are known for their large nervous systems, complex behaviors and morphological innovations. To investigate the genomic underpinnings of these features, we assembled the chromosomes of the Boston market squid, Doryteuthis (Loligo) pealeii, and the California two-spot octopus, Octopus bimaculoides , and compared them with those of the Hawaiian bobtail squid, Euprymna scolopes . The genomes of the soft-bodied (coleoid) cephalopods are highly rearranged relative to other extant molluscs, indicating an intense, early burst of genome restructuring. The coleoid genomes feature multi-megabase, tandem arrays of genes associated with brain development and cephalopod-specific innovations. We find that a known coleoid hallmark, extensive A-to-I mRNA editing, displays two fundamentally distinct patterns: one exclusive to the nervous system and concentrated in genic sequences, the other widespread and directed toward repetitive elements. We conclude that coleoid novelty is mediated in part by substantial genome reorganization, gene family expansion, and tissue-dependent mRNA editing. “Cephalopods are known for their large nervous systems, complex behaviors, and morphological innovations. Here, the authors find that soft-bodied cephalopod genomes are more rearranged than other extant molluscs and that mRNA editing patterns are associated with the nervous system and repetitive elements”.

Girderless monolithic floors represent the main constructive technique primarily for residential buildings – an important component is the saving of space in contrast to girder structures. In addition, these structures are typical for other buildings. The issue of punching in monolithic girderless ceilings is one of the most important issues. At the same time, as a rule, only one task is solved – reinforcement from punching and the issue of the stress-strain state of the structure as a whole is completely ignored. This fact leads to an uncharacteristic redistribution of forces in the structure, which ultimately leads to destruction. This article discusses specific examples of calculations and objects with an analysis of the redistribution of moments and the final convergence of the calculation results. In conclusion, the key conclusions are made

Although it is widely believed that early vertebrate evolution was shaped by ancient whole-genome duplications, the number, timing and mechanism of these events remain elusive. Here, we infer the history of vertebrates through genomic comparisons with a new chromosome-scale sequence of the invertebrate chordate amphioxus. We show how the karyotypes of amphioxus and diverse vertebrates are derived from 17 ancestral chordate linkage groups (and 19 ancestral bilaterian groups) by fusion, rearrangement and duplication. We resolve two distinct ancient duplications based on patterns of chromosomal conserved synteny. All extant vertebrates share the first duplication, which occurred in the mid/late Cambrian by autotetraploidization (that is, direct genome doubling). In contrast, the second duplication is found only in jawed vertebrates and occurred in the mid–late Ordovician by allotetraploidization (that is, genome duplication following interspecific hybridization) from two now-extinct progenitors. This complex genomic history parallels the diversification of vertebrate lineages in the fossil record. Genomic comparisons with a new amphioxus chromosome-scale genome assembly reveal details of the early evolution of vertebrate genomes.

Octopus bimaculoides genome and transcriptome sequencing demonstrated that a core gene repertoire broadly similar to that of other invertebrate bilaterians is accompanied by expansions in the protocadherin and C2H2 zinc-finger transcription factor families and large-scale genome rearrangements closely associated with octopus-specific transposable elements. Octopus genome reveals secrets of a complex cephalopod Octopuses have been called 'the most intelligent invertebrate', with a host of complex behaviours, and a nervous system comparable in size to that of mammals but organized in a very different manner. It had been hypothesized that, as in vertebrates, whole-genome duplication contributed to the evolution of this complex nervous system. Caroline Albertin et al . have sequenced the genome and multiple transcriptomes of the California two-spot octopus ( Octopus bimaculoides ) and find no evidence for such duplications but there are large-scale genome rearrangements closely associated with octopus-specific transposable elements. The core developmental and neuronal gene repertoire turns out to be broadly similar to that of other invertebrates, apart from expansions in two gene families formerly thought to be uniquely expanded in vertebrates — the protocadherins (cell-adhesion molecules that regulate neural development) and the C2H2 superfamily of zinc-finger transcription factors. Coleoid cephalopods (octopus, squid and cuttlefish) are active, resourceful predators with a rich behavioural repertoire 1 . They have the largest nervous systems among the invertebrates 2 and present other striking morphological innovations including camera-like eyes, prehensile arms, a highly derived early embryogenesis and a remarkably sophisticated adaptive colouration system 1 , 3 . To investigate the molecular bases of cephalopod brain and body innovations, we sequenced the genome and multiple transcriptomes of the California two-spot octopus, Octopus bimaculoides . We found no evidence for hypothesized whole-genome duplications in the octopus lineage 4 , 5 , 6 . The core developmental and neuronal gene repertoire of the octopus is broadly similar to that found across invertebrate bilaterians, except for massive expansions in two gene families previously thought to be uniquely enlarged in vertebrates: the protocadherins, which regulate neuronal development, and the C2H2 superfamily of zinc-finger transcription factors. Extensive messenger RNA editing generates transcript and protein diversity in genes involved in neural excitability, as previously described 7 , as well as in genes participating in a broad range of other cellular functions. We identified hundreds of cephalopod-specific genes, many of which showed elevated expression levels in such specialized structures as the skin, the suckers and the nervous system. Finally, we found evidence for large-scale genomic rearrangements that are closely associated with transposable element expansions. Our analysis suggests that substantial expansion of a handful of gene families, along with extensive remodelling of genome linkage and repetitive content, played a critical role in the evolution of cephalopod morphological innovations, including their large and complex nervous systems.

Coleoid cephalopods (squid, cuttlefish, octopus) have the largest nervous system among invertebrates that together with many lineage-specific morphological traits enables complex behaviors. The genomic basis underlying these innovations remains unknown. Using comparative and functional genomics in the model squid Euprymna scolopes , we reveal the unique genomic, topological, and regulatory organization of cephalopod genomes. We show that coleoid cephalopod genomes have been extensively restructured compared to other animals, leading to the emergence of hundreds of tightly linked and evolutionary unique gene clusters (microsyntenies). Such novel microsyntenies correspond to topological compartments with a distinct regulatory structure and contribute to complex expression patterns. In particular, we identify a set of microsyntenies associated with cephalopod innovations (MACIs) broadly enriched in cephalopod nervous system expression. We posit that the emergence of MACIs was instrumental to cephalopod nervous system evolution and propose that microsyntenic profiling will be central to understanding cephalopod innovations. Cephalopods are an enigmatic animal group with complex and adaptive behaviors such as camouflage; however the genetic basis for these traits is not well understood. Here the authors reveal a set of cephalopod-restricted rearranged genomic loci, involving known neuronal regulators but also unexpected gene families, that confer topological organization and gene regulation.

Lungfishes belong to lobe-fined fish (Sarcopterygii) that, in the Devonian period, ‘conquered’ the land and ultimately gave rise to all land vertebrates, including humans 1 – 3 . Here we determine the chromosome-quality genome of the Australian lungfish ( Neoceratodus forsteri ), which is known to have the largest genome of any animal. The vast size of this genome, which is about 14× larger than that of humans, is attributable mostly to huge intergenic regions and introns with high repeat content (around 90%), the components of which resemble those of tetrapods (comprising mainly long interspersed nuclear elements) more than they do those of ray-finned fish. The lungfish genome continues to expand independently (its transposable elements are still active), through mechanisms different to those of the enormous genomes of salamanders. The 17 fully assembled lungfish macrochromosomes maintain synteny to other vertebrate chromosomes, and all microchromosomes maintain conserved ancient homology with the ancestral vertebrate karyotype. Our phylogenomic analyses confirm previous reports that lungfish occupy a key evolutionary position as the closest living relatives to tetrapods 4 , 5 , underscoring the importance of lungfish for understanding innovations associated with terrestrialization. Lungfish preadaptations to living on land include the gain of limb-like expression in developmental genes such as hoxc13 and sall1 in their lobed fins. Increased rates of evolution and the duplication of genes associated with obligate air-breathing, such as lung surfactants and the expansion of odorant receptor gene families (which encode proteins involved in detecting airborne odours), contribute to the tetrapod-like biology of lungfishes. These findings advance our understanding of this major transition during vertebrate evolution. A chromosome-quality genome of the lungfish Neoceratodus fosteri sheds light on the development of obligate air-breathing and the gain of limb-like gene expression in lobed fins, providing insights into the water-to-land transition in vertebrate evolution.

The external reinforcement system based on carbon fiber has been used for decades to strengthen reinforced concrete elements. At the same time, it is impossible not to recognize that the existing calculation methods are largely based on empirical dependencies obtained from experimental studies. One of these issues is related to the application of the methodology for materials of heterogeneous origin-tapes and laminates. In general, the possibility of applying the calculation methods accepted in the norms for laminates of generally accepted thicknesses up to 1.6 mm is determined. The question related to the possibility of using laminates of greater thickness is not sufficiently studied. This article deals with the calculation of the reinforcement of the normal cross sections of the bent reinforced concrete elements with the reinforcement of laminates with a thickness of 5 mm.

Microchromosomes, once considered unimportant shreds of the chicken genome, are gene-rich elements with a high GC content and few transposable elements. Their origin has been debated for decades. We used cytological and whole-genome sequence comparisons, and chromosome conformation capture, to trace their origin and fate in genomes of reptiles, birds, and mammals. We find that microchromosomes as well as macrochromosomes are highly conserved across birds and share synteny with single small chromosomes of the chordate amphioxus, attesting to their origin as elements of an ancient animal genome. Turtles and squamates (snakes and lizards) share different subsets of ancestral microchromosomes, having independently lost microchromosomes by fusion with other microchromosomes or macrochromosomes. Patterns of fusions were quite different in different lineages. Cytological observations show that microchromosomes in all lineages are spatially separated into a central compartment at interphase and during mitosis and meiosis. This reflects higher interaction between microchromosomes than with macrochromosomes, as observed by chromosome conformation capture, and suggests some functional coherence. In highly rearranged genomes fused microchromosomes retain most ancestral characteristics, but these may erode over evolutionary time; surprisingly, de novo microchromosomes have rapidly adopted high interaction. Some chromosomes of early-branching monotreme mammals align to several bird microchromosomes, suggesting multiple microchromosome fusions in a mammalian ancestor. Subsequently, multiple rearrangements fueled the extraordinary karyotypic diversity of therian mammals. Thus, microchromosomes, far from being aberrant genetic elements, represent fundamental building blocks of amniote chromosomes, and it is mammals, rather than reptiles and birds, that are atypical.

The article considers the issue of repair of masonry that has received specific damage as a result of explosive dynamic impacts. The characteristic variants of masonry damage are considered, based on the operating stresses. A detailed analysis of the mechanisms of the masonry work in case of damage as a result of an explosion, as well as after reinforcement with an external application of shotcrete was carried out. The practical aspects of the use of shotcrete to strengthen masonry that has been destroyed as a result of explosive dynamic effects are considered, in terms of the features of the interaction of the external application with the masonry, the stages of work on the application of shotcrete in order to effectively include reinforcement elements in the work, the key physical and mechanical characteristics of shotcrete. The results of practical application of masonry reinforcement technology by external applications for a specific multi-storey building damaged as a result of explosive impacts are presented. Based on the results, the conclusion is made