scholarly journals Three-dimensional visualization as a tool for interpreting locomotion strategies in ophiuroids from the Devonian Hunsrück Slate

2020 ◽  
Vol 7 (12) ◽  
pp. 201380
Author(s):  
E. G. Clark ◽  
J. R. Hutchinson ◽  
D. E. G. Briggs
Keyword(s):  
Evolutionary History ◽  
Lower Devonian ◽  
Soft Tissues ◽  
Three Dimensional ◽  
Hunsrück Slate ◽  
Brittle Stars ◽  
History Of ◽  
First Time

Living brittle stars (Echinodermata: Ophiuroidea) employ a very different locomotion strategy to that of any other metazoan: five or more arms coordinate powerful strides for rapid movement across the ocean floor. This mode of locomotion is reliant on the unique morphology and arrangement of multifaceted skeletal elements and associated muscles and other soft tissues. The skeleton of many Palaeozoic ophiuroids differs markedly from that in living forms, making it difficult to infer their mode of locomotion and, therefore, to resolve the evolutionary history of locomotion in the group. Here, we present three-dimensional digital renderings of specimens of six ophiuroid taxa from the Lower Devonian Hunsrück Slate: four displaying the arm structure typical of Palaeozoic taxa ( Encrinaster roemeri, Euzonosoma tischbeinianum, Loriolaster mirabilis, Cheiropteraster giganteus ) and two ( Furcaster palaeozoicus , Ophiurina lymani ) with morphologies more similar to those in living forms. The use of three-dimensional digital visualization allows the structure of the arms of specimens of these taxa to be visualized in situ in the round, to our knowledge for the first time. The lack of joint interfaces necessary for musculoskeletally-driven locomotion supports the interpretation that taxa with offset ambulacrals would not be able to conduct this form of locomotion, and probably used podial walking. This approach promises new insights into the phylogeny, functional morphology and ecological role of Palaeozoic brittle stars.

scholarly journals Convergent evolution of olfactory and thermoregulatory capacities in small amphibious mammals

2020 ◽  
Vol 117 (16) ◽  
pp. 8958-8965 ◽  
Author(s):  
Quentin Martinez ◽  
Julien Clavel ◽  
Jacob A. Esselstyn ◽  
Anang S. Achmadi ◽  
Camille Grohé ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Phylogenetic Diversity ◽  
Soft Tissues ◽  
Three Dimensional ◽  
Aquatic Environments ◽  
Evolutionary Models ◽  
Trade Off ◽  
Avoidance Behaviors ◽  
Vital Functions ◽  
History Of

Olfaction and thermoregulation are key functions for mammals. The former is critical to feeding, mating, and predator avoidance behaviors, while the latter is essential for homeothermy. Aquatic and amphibious mammals face olfactory and thermoregulatory challenges not generally encountered by terrestrial species. In mammals, the nasal cavity houses a bony system supporting soft tissues and sensory organs implicated in either olfactory or thermoregulatory functions. It is hypothesized that to cope with aquatic environments, amphibious mammals have expanded their thermoregulatory capacity at the expense of their olfactory system. We investigated the evolutionary history of this potential trade-off using a comparative dataset of three-dimensional (3D) CT scans of 189 skulls, capturing 17 independent transitions from a strictly terrestrial to an amphibious lifestyle across small mammals (Afrosoricida, Eulipotyphla, and Rodentia). We identified rapid and repeated loss of olfactory capacities synchronously associated with gains in thermoregulatory capacity in amphibious taxa sampled from across mammalian phylogenetic diversity. Evolutionary models further reveal that these convergences result from faster rates of turbinal bone evolution and release of selective constraints on the thermoregulatory-olfaction trade-off in amphibious species. Lastly, we demonstrated that traits related to vital functions evolved faster to the optimum compared to traits that are not related to vital functions.

Elaborating the role of reflection and individual differences in the study of folk-economic beliefs

2018 ◽  
Vol 41 ◽  
Author(s):  
Kevin Arceneaux
Keyword(s):  
Decision Making ◽  
Individual Differences ◽  
Cognitive Processes ◽  
Evolutionary History ◽  
Behavioral Responses ◽  
History Of ◽  
Economic Beliefs

AbstractIntuitions guide decision-making, and looking to the evolutionary history of humans illuminates why some behavioral responses are more intuitive than others. Yet a place remains for cognitive processes to second-guess intuitive responses – that is, to be reflective – and individual differences abound in automatic, intuitive processing as well.

scholarly journals EXPRESS: Pulmonary Hypertension Associated With Neurofibromatosis Type 2

2021 ◽  
pp. 204589402110295
Author(s):  
Hirohisa Taniguchi ◽  
Tomoya Takashima ◽  
Ly Tu ◽  
Raphaël Thuillet ◽  
Asuka Furukawa ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Neurofibromatosis Type ◽  
Pulmonary Vascular Remodeling ◽  
Life Threatening ◽  
History Of ◽  
Pulmonary Arterial ◽  
First Time

Although precapillary pulmonary hypertension (PH) is a rare but severe complication of patients with neurofibromatosis type 1 (NF1), its association with NF2 remains unknown. Herein, we report a case of a 44-year-old woman who was initially diagnosed with idiopathic pulmonary arterial hypertension (IPAH) and treated with PAH-specific combination therapy. However, a careful assessment for a relevant family history of the disease and genetic testing reveal that this patient had a mutation in the NF2 gene. Using immunofluorescence and Western blotting, we demonstrated a decrease in endothelial NF2 protein in lungs from IPAH patients compared to control lungs, suggesting a potential role of NF2 in PAH development. To our knowledge, this is the first time that precapillary PH has been described in a patient with NF2. The altered endothelial NF2 expression pattern in PAH lungs should stimulate work to better understand how NF2 is contributing to the pulmonary vascular remodeling associated to these severe life-threatening conditions.

scholarly journals Gut bacteria are essential for normal cuticle development in herbivorous turtle ants

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Christophe Duplais ◽  
Vincent Sarou-Kanian ◽  
Dominique Massiot ◽  
Alia Hassan ◽  
Barbara Perrone ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Nitrogen Assimilation ◽  
Isotope Ratio Mass Spectrometry ◽  
Gut Bacteria ◽  
Resonance Spectroscopy ◽  
Nitrogen Flow ◽  
Isotopic Enrichment ◽  
History Of ◽  
Cuticle Development

AbstractAcross the evolutionary history of insects, the shift from nitrogen-rich carnivore/omnivore diets to nitrogen-poor herbivorous diets was made possible through symbiosis with microbes. The herbivorous turtle ants Cephalotes possess a conserved gut microbiome which enriches the nutrient composition by recycling nitrogen-rich metabolic waste to increase the production of amino acids. This enrichment is assumed to benefit the host, but we do not know to what extent. To gain insights into nitrogen assimilation in the ant cuticle we use gut bacterial manipulation, 15N isotopic enrichment, isotope-ratio mass spectrometry, and 15N nuclear magnetic resonance spectroscopy to demonstrate that gut bacteria contribute to the formation of proteins, catecholamine cross-linkers, and chitin in the cuticle. This study identifies the cuticular components which are nitrogen-enriched by gut bacteria, highlighting the role of symbionts in insect evolution, and provides a framework for understanding the nitrogen flow from nutrients through bacteria into the insect cuticle.

Early origin of sweet perception in the songbird radiation

Science ◽  
2021 ◽  
Vol 373 (6551) ◽  
pp. 226-231 ◽  
Author(s):  
Yasuka Toda ◽  
Meng-Ching Ko ◽  
Qiaoyi Liang ◽  
Eliot T. Miller ◽  
Alejandro Rico-Guevara ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Genetic Basis ◽  
Sensory Biology ◽  
Avian Evolution ◽  
Nectar Feeding ◽  
Evolutionary Radiation ◽  
History Of ◽  
Sensory Convergence ◽  
Early Origin

Early events in the evolutionary history of a clade can shape the sensory systems of descendant lineages. Although the avian ancestor may not have had a sweet receptor, the widespread incidence of nectar-feeding birds suggests multiple acquisitions of sugar detection. In this study, we identify a single early sensory shift of the umami receptor (the T1R1-T1R3 heterodimer) that conferred sweet-sensing abilities in songbirds, a large evolutionary radiation containing nearly half of all living birds. We demonstrate sugar responses across species with diverse diets, uncover critical sites underlying carbohydrate detection, and identify the molecular basis of sensory convergence between songbirds and nectar-specialist hummingbirds. This early shift shaped the sensory biology of an entire radiation, emphasizing the role of contingency and providing an example of the genetic basis of convergence in avian evolution.

scholarly journals Features of positioning of German university libraries on official websites

2021 ◽  
pp. 43-52
Author(s):  
N. Khymytsia ◽  
M. Kuchma
Keyword(s):  
Rock Music ◽  
Music Programs ◽  
University Libraries ◽  
Sound Recordings ◽  
Cultural Phenomenon ◽  
Creative Music ◽  
History Of ◽  
Historical Phenomenon ◽  
First Time

The problem of space music as a special cultural phenomenon requires scientific understanding. The purpose of the article is to study the features of the emergence and development of space rock as a specific trend in modern popular culture using the history of the “HAWKWIND” group as an example. The chronology of sound recordings of the “HAWKWIND” group as one of the founders of the “Space Rock Music” is established. The role of Dave Broсk, Bob Kalvert and other group participants in the creation of creative music programs is noted. It is proved that these musicians are the principles of the historical phenomenon, which received popularity as “Space Rock”. For the first time, the analysis of “HAWKWIND” sound documents through the prism of the history of space music development has been proposed.

scholarly journals Transport and localization of exogenous myelin basic protein mRNA microinjected into oligodendrocytes.

1993 ◽  
Vol 123 (2) ◽  
pp. 431-441 ◽  
Author(s):  
K Ainger ◽  
D Avossa ◽  
F Morgan ◽  
S J Hill ◽  
C Barry ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Living Cells ◽  
Branch Points ◽  
Rna Granules ◽  
Intracellular Movement ◽  
Directional Movement ◽  
Ionic Detergent ◽  
Mrna Granules

We have studied transport and localization of MBP mRNA in oligodendrocytes in culture by microinjecting labeled mRNA into living cells and analyzing the intracellular distribution of the injected RNA by confocal microscopy. Injected mRNA initially appears dispersed in the perikaryon. Within minutes, the RNA forms granules which, in the case of MBP mRNA, are transported down the processes to the periphery of the cell where the distribution again becomes dispersed. In situ hybridization shows that endogenous MBP mRNA in oligodendrocytes also appears as granules in the perikaryon and processes and dispersed in the peripheral membranes. The granules are not released by extraction with non-ionic detergent, indicating that they are associated with the cytoskeletal matrix. Three dimensional visualization indicates that MBP mRNA granules are often aligned in tracks along microtubules traversing the cytoplasm and processes. Several distinct patterns of granule movement are observed. Granules in the processes undergo sustained directional movement with a velocity of approximately 0.2 micron/s. Granules at branch points undergo oscillatory motion with a mean displacement of 0.1 micron/s. Granules in the periphery of the cell circulate randomly with a mean displacement of approximately 1 micron/s. The results are discussed in terms of a multi-step pathway for transport and localization of MBP mRNA in oligodendrocytes. This work represents the first characterization of intracellular movement of mRNA in living cells, and the first description of the role of RNA granules in transport and localization of mRNA in cells.

Adaptive convergent evolution of genome proofreading in SARS-CoV2: insights into the Eigen’s paradox

2021 ◽  
Author(s):  
Keerthic Aswin ◽  
Srinivasan Ramachandran ◽  
Vivek T Natarajan
Keyword(s):  
Convergent Evolution ◽  
Genome Stability ◽  
Evolutionary History ◽  
Rna Binding ◽  
Phylogenetic Analyses ◽  
Comparative Genome Analysis ◽  
The Family ◽  
History Of ◽  
Key Residues

AbstractEvolutionary history of coronaviruses holds the key to understand mutational behavior and prepare for possible future outbreaks. By performing comparative genome analysis of nidovirales that contain the family of coronaviruses, we traced the origin of proofreading, surprisingly to the eukaryotic antiviral component ZNFX1. This common recent ancestor contributes two zinc finger (ZnF) motifs that are unique to viral exonuclease, segregating them from DNA proof-readers. Phylogenetic analyses indicate that following acquisition, genomes of coronaviruses retained and further fine-tuned proofreading exonuclease, whereas related families harbor substitution of key residues in ZnF1 motif concomitant to a reduction in their genome sizes. Structural modelling followed by simulation suggests the role of ZnF in RNA binding. Key ZnF residues strongly coevolve with replicase, and the helicase involved in duplex RNA unwinding. Hence, fidelity of replication in coronaviruses is a result of convergent evolution, that enables maintenance of genome stability akin to cellular proofreading systems.

Historiosophy of N.Ya. Danilevsky

2020 ◽  
Vol 58 ◽  
pp. 13-17
Author(s):  
Victor V. Aksyuchits
Keyword(s):  
20Th Century ◽  
World History ◽  
Russian Culture ◽  
Russian People ◽  
The World ◽  
History Of ◽  
First Time

According to the author of the article, N.Ya. Danilevsky anticipated a lot of ideas of the 20th century, in particular those of O. Spengler and A. Toynbee, by offering his concept of cultural and historical types in the book “Russia and Europe”. At the same time N.Ya. Danilevsky was in many aspects the follower of Slavophils while interpreting the originality of Russian people and Russian culture. After the turn of the educated society circles to Russian national self-comprehension initiated by Slavophils, N.Ya. Danilevsky not only scientifically formulated the problems brought forth by the Slavophils, but also offered for the first time the resolution of new important questions by analyzing the world history and the history of Slavic peoples. The author especially stresses the role of N.Ya. Danilevsky in creating the historiosophic concept that forestalled the epoch for many decades.

Agafonov’s Early Kharkiv Creative Period: Dialogue with the Theatre

2020 ◽  
Vol 2020 (3) ◽  
pp. 82-93
Author(s):  
V. Chechyk ◽  
Keyword(s):  
Art History ◽  
Artistic Practice ◽  
Partial Reconstruction ◽  
Theatrical Space ◽  
Native Art ◽  
History Of ◽  
Artistic Values ◽  
First Time ◽  
History Of Formation

This article is dedicated to the study of the nature of E. Agafonov’s creative ties with the theater – a topic that has been insufficiently covered in the native art history. The author’s field of view is set in the artist’s early Kharkiv period, marked as the years of 1905–1913. The article focuses on the exceptional role of E. Agafonov in the organization and the artistic practice of the first modernist theater “Blakytne Oko” in Kharkiv (1909–1911). Agafonov belonged to the constellation of masters who was very sensitive to the problem of evolving the artistic speech. He viewed the theater as a convincing platform for promoting and approving of the latest artistic values, discovered by Impressionism and Post-Impressionism. Experiments in easel art (with color, plastic, line, techniques, materials, etc.), largely inspired by the work of D. Burliuk (1906–1908), were directly reflected in Agafonov’s stage practice, namely in numerous designs of the modernist productions based on plays by M. Maeterlinkc, A. Schnitzler, S. Pshybyshevsky and O. Blok. In turn, it was established that theatrical motives were reflected in E. Agafonov’s easel art, as well as in the art of the students of his artistic studio – O. Rybnikov, I. Terentyev, M. Sinyakova, and K. Storozhnichenko. In this regard, a special attention is given to the linocuts by F. Nadezhdin. It was found that the program of “total” design of theatrical space (stage and auditorium), as well as the implementation of production ideas in the cabaret theater “Blakytne Oko” were the result of the master’s fascination with the concepts of artistic synthesis, actualized in the era of Modern. Agafonov moved from dramatization of paintings (of A. Beklin, F. Malyavin, and O. Rodin) to staging experimental show-programs like “The Evening of Autumn”, “Visiting Pierrot” and “In the Middle of Nowhere”, partial reconstruction of which was undertaken for the first time by the author of the article. Agafonov was close to the idea of artistic synthesis, identified by him in F. Malyavin’s paintings, in V. Komissarzhevska’s theatre and I. Duncan’s choreography. The study of E. Agafanov’s theatrical art expands the understanding of the history of formation and development of Ukrainian scenography at the beginning of the twentieth century.

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