Symbiotic bacteria on the cuticle of the leaf-cutting ant
            Acromyrmex subterraneus subterraneus
            protect workers from attack by entomopathogenic fungi

Although only discovered in 1999, the symbiotic filamentous actinobacteria present on the integument of certain species of leaf-cutting ants have been the subject of intense research. These bacteria have been shown to specifically suppress fungal garden parasites by secretion of antibiotics. However, more recently, a wider role for these bacteria has been suggested from research revealing their generalist anti-fungal activity. Here we show, for the first time, evidence for a role of these bacteria in the defence of young worker ants against a fungal entomopathogen. Experimental removal of the bacterial bio-film using an antibiotic resulted in a significant increase in susceptibility of worker ants to infection by the entomopathogenic fungus Metarhizium anisopliae . This is the first direct evidence for the advantage of maintaining a bacterial bio-film on the cuticle as a defensive strategy of the ants themselves and not exclusively for protection of the fungus garden.

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Tadpoles of hybridising fire-bellied toads (B. bombina and B. variegata) differ in their susceptibility to predation

PLoS ONE ◽

10.1371/journal.pone.0231804 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0231804

Author(s):

Radovan Smolinský ◽

Vojtech Baláž ◽

Beate Nürnberger

Keyword(s):

Direct Evidence ◽

Adaptive Divergence ◽

Differential Adaptation ◽

Risk Of Predation ◽

Distribution Ranges ◽

Bombina Bombina ◽

Recent Debate ◽

The Subject ◽

Genomic Regions

The role of adaptive divergence in the formation of new species has been the subject of much recent debate. The most direct evidence comes from traits that can be shown to have diverged under natural selection and that now contribute to reproductive isolation. Here, we investigate differential adaptation of two fire-bellied toads (Anura, Bombinatoridae) to two types of aquatic habitat. Bombina bombina and B. variegata are two anciently diverged taxa that now reproduce in predator-rich ponds and ephemeral aquatic sites, respectively. Nevertheless, they hybridise extensively wherever their distribution ranges adjoin. We show in laboratory experiments that, as expected, B. variegata tadpoles are at relatively greater risk of predation from dragonfly larvae, even when they display a predator-induced phenotype. These tadpoles spent relatively more time swimming and so prompted more attacks from the visually hunting predators. We argue in the discussion that genomic regions linked to high activity in B. variegata should be barred from introgression into the B. bombina gene pool and thus contribute to gene flow barriers that keep the two taxa from merging into one.

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Towards the realistic computer model of precipitation polymerization microgels

Scientific Reports ◽

10.1038/s41598-019-49512-3 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 9

Author(s):

Vladimir Yu. Rudyak ◽

Elena Yu. Kozhunova ◽

Alexander V. Chertovich

Keyword(s):

Computer Simulations ◽

Precipitation Polymerization ◽

Coarse Grained ◽

Polymerization Process ◽

New Horizons ◽

Experimental Systems ◽

Structure Factors ◽

The Subject ◽

First Time

Abstract In this paper we propose a new method of coarse-grained computer simulations of the microgel formation in course of free radical precipitation polymerization. For the first time, we simulate the precipitation polymerization process from a dilute solution of initial components to a final microgel particle with coarse grained molecular dynamics, and compare it to the experimental data. We expect that our simulation studies of PNIPA-like microgels will be able to elucidate the subject of nucleation and growth kinetics and to describe in detail the network topology and structure. Performed computer simulations help to determine the characteristic phases of the growth process and show the necessity of prolongated synthesis for the formation of stable microgel particles. We demonstrate the important role of dangling ends in microgels, which occupy as much as 50% of its molecular mass and have previously unattended influence on the swelling behavior. The verification of the model is made by the comparison of collapse curves and structure factors between simulated and experimental systems, and high quality matching is achieved. This work could help to open new horizons in studies that require the knowledge of detailed and realistic structures of the microgel networks.

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Social Carrying and Defensive Behavior During Colony Emigration in the Leaf-cutting Ant Atta sexdens

Sociobiology ◽

10.13102/sociobiology.v64i4.2087 ◽

2017 ◽

Vol 64 (4) ◽

pp. 492

Author(s):

Lohan Valadares ◽

Fábio S. Nascimento

Keyword(s):

Body Surface ◽

Defensive Behavior ◽

The Body ◽

Fungus Garden ◽

Atta Sexdens ◽

Defensive Strategies ◽

Laboratory Conditions ◽

Nesting Site ◽

Leaf Cutting ◽

First Time

In this work, we describe for the first time and under laboratory conditions, the behaviors related to social carrying and defensive strategies during colony emigration in the leaf-cutting ant Atta sexdens. Once colonies were laid on a tray under suboptimal conditions, groups of workers aggregated all over the body surface of the queen and brood, with mandibles half open and legs widely open in a ‘entangle’ formation. Queens were the first caste to be reallocated, followed respectively by the transportation of brood, newly-emerged workers, and pieces of fungus garden to the new nesting site. Contrary to what have been reported to the Myrmicinae species, adult transport followed a stereotyped sequence of acts involving approach, seize and transportation of newly-emerged workers to new target areas. Our results suggest that, in front of rapid unfavorable changes, leaf-cutting ants are capable of reorganize the nest in order to protect their members and resources.

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Propensity of undulatory swimmers, such as worms, to go against the flow

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1424962112 ◽

2015 ◽

Vol 112 (12) ◽

pp. 3606-3611 ◽

Cited By ~ 7

Author(s):

Jinzhou Yuan ◽

David M. Raizen ◽

Haim H. Bau

Keyword(s):

Control Strategies ◽

Aquatic Organisms ◽

Life Cycles ◽

Environmental Cues ◽

Mechanical Forces ◽

C Elegans ◽

The Subject ◽

And Function ◽

First Time

The ability to orient oneself in response to environmental cues is crucial to the survival and function of diverse organisms. One such orientation behavior is the alignment of aquatic organisms with (negative rheotaxis) or against (positive rheotaxis) fluid current. The questions of whether low-Reynolds-number, undulatory swimmers, such as worms, rheotax and whether rheotaxis is a deliberate or an involuntary response to mechanical forces have been the subject of conflicting reports. To address these questions, we use Caenorhabditis elegans as a model undulatory swimmer and examine, in experiment and theory, the orientation of C. elegans in the presence of flow. We find that when close to a stationary surface the animal aligns itself against the direction of the flow. We elucidate for the first time to our knowledge the mechanisms of rheotaxis in worms and show that rheotaxis can be explained solely by mechanical forces and does not require sensory input or deliberate action. The interaction between the flow field induced by the swimmer and a nearby surface causes the swimmer to tilt toward the surface and the velocity gradient associated with the flow rotates the animal to face upstream. Fluid mechanical computer simulations faithfully mimic the behavior observed in experiments, supporting the notion that rheotaxis behavior can be fully explained by hydrodynamics. Our study highlights the important role of hydrodynamics in the behavior of small undulating swimmers and may assist in developing control strategies to affect the animals’ life cycles.

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Technology as a factor in the cultural development of mankind: a study of the production nature of primitive culture

National Academy of Managerial Staff of Culture and Arts Herald ◽

10.32461/2226-3209.2.2021.239931 ◽

2021 ◽

pp. 57-60

Author(s):

Tetiana Sovhyra

Keyword(s):

Art History ◽

Integrated Approach ◽

Cultural Development ◽

Fire Control ◽

Production Technologies ◽

The Subject ◽

Organization Of Production ◽

First Time ◽

Metal Melting

Purpose of article. Explore technological progress in the context of the development of a primitive culture. The methodology is based on an integrated approach and relies on analytical (when analyzing philosophical, art history, cultural studies literature on the subject of research), historical (when clarifying the stages of development of primitive culture), and conceptual (when analyzing the role of technology in the cultural development of mankind) research methods. The scientific novelty of the article lies in the fact that for the first time the formative role of technology in the cultural development of mankind is investigated, and also the cooperative nature of the production of artifacts of primitive culture is determined. Conclusions. As a result of the study of archaeological finds of primitive culture, it has been established that in the course of cultural evolution, tools of labor have become cultural artifacts, works of art. The emergence of production technologies (stone processing, fire control, metal melting) radically transformed the specifics of the organization of production activities, and therefore changed the course of cultural development. Therefore, in the course of the study, the formative role of technology in the formation of artistic culture was proved.

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Efficient Emission in Halide Layered Double Perovskites: The Role of Sb3+ Substitution in Cs4Cd1–xMnxBi2Cl12 Phosphors

10.26434/chemrxiv.12950804.v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Brenda Vargas ◽

Eduardo Coutiño-Gonzalez ◽

Oscar Ovalle-Encinia ◽

Citlali Sánchez-Aké ◽

Diego Solis-Ibarra

Keyword(s):

Optoelectronic Properties ◽

Double Perovskites ◽

Spin Orbit Coupling ◽

Fixed Amount ◽

Electronic Delocalization ◽

The Subject ◽

Halide Perovskites ◽

Pl Emission ◽

Intense Research

Layered halide perovskites and double perovskites optoelectronic properties have recently been the subject of intense research. Layered double perovskites represent the merging of both worlds, and as such, have the potential to further expand the already vast space of optoelectronic properties and applications of halide perovskites. Despite having more than 40 known members, to date, only the <111>-oriented layered double perovskites: Cs4Cd1–xMnxBi2Cl12, have shown efficient photoluminescence (PL). In this work, we replaced Bi with Sb to further investigate the electronic structure and PL properties of these materials, resulting in two new families of layered inorganic perovskites alloys with full solubility. The first family, Cs4Cd1–xMnSb2Cl12, exhibits a PL emission at 605 nm ascribed to Mn2+ centers in octahedral coordination, and a maximum photoluminescence quantum yield PLQY of 28.5%. The second family of alloys, also with full solubility, Cs4Cd0.8Mn0.2(Sb1–yBiy)2Cl12, contains a fixed amount of Mn2+ and Cd2+ cations but different concentrations of the trivalent metals. This variability allows the tuning of the PL emission from 603 nm to 614 nm. We show that the decreased efficiency of the Cs4Cd1–xMnxSb2Cl12family compared to Cs4Cd1–xMnxBi2Cl12, is mostly due to a decreased spin-orbit coupling in Sb and the subsequent increased electronic delocalization compared to the Bi alloys, reducing the energy transfer to Mn2+ centers. This work lays out a roadmap to understand and achieve high photoluminescence efficiencies in layered double perovskites.

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The emergence and proliferation of the shaloput sect in the Pavlograd district of the Yekaterinoslav province (second half of the 19th century)

V. N. Karazin Kharkiv National University Bulletin "History of Ukraine. Ukrainian Studies: Historical and Philosophical Sciences" ◽

10.26565/2227-6505-2020-31-04 ◽

2020 ◽

Keyword(s):

Rural Community ◽

Russian Orthodox ◽

Russian Orthodox Church ◽

Special Scientific ◽

Analysis And Synthesis ◽

History Of ◽

The Subject ◽

The 19Th Century ◽

First Time

Purpose. The article aims to highlight the history of the emergence and spread of the shaloput sect in the Pavlograd district of the Yekaterinoslav province. Research methodology. The methodological basis of the article is formed by the principles of historicism and objectivity, implemented using several methods: general logical (analysis and synthesis), as well as classification, comparative, and periodization methods. Scientific novelty. For the first time in Russian historiography, the subject of a special scientific study was the sect of pranksters and its activities in the Yekaterinoslav province. Based on missionary and police reports, the role of Grigory Shevchenko in the creation of the sect is considered, the area of its distribution within the region is highlighted, the national and social composition of its members is determined. Conclusions. It has been established that Grigory Shevchenko brought in the Pavlograd district of the Yekaterinoslav province the shaloput doctrine from the southern Ukrainian regions, probably from the Tauride province. The sect he created was by its nature Christover or Khlyst. Its dogmas and ceremonial were of a pronounced mystical coloring. Grigory Shevchenko remained a completely independent leader of a group of his fellow believers, he did not belong to any more ramified community, and his community throughout its existence remained an autonomous unit. The attitude of the dignitaries of the Russian Orthodox Church and representatives of the secular authorities to the new religious organization was extremely negative. Various means of pressure were used against the sectarians: from forced interviews to sentences of the rural community and outright repression by punitive bodies.

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Russian explanatory sentence as a semantic type

Sibirskiy filologicheskiy zhurnal ◽

10.17223/18137083/76/20 ◽

2021 ◽

pp. 272-286

Author(s):

Tatiana I. Steksova ◽

◽

Tatyana V. Shmeleva ◽

Keyword(s):

Semantic Features ◽

Semantic Type ◽

Complex Sentences ◽

The Subject ◽

Semantic Types ◽

First Time

The paper interprets the Russian explanatory sentence as a semantic type. It is noted that descriptions of the semantic types of monopropositional sentences have already been carried out in the linguistic literature. For the first time, it is proposed to consider polypropositional semantic structures as a semantic type. The semantic nature of an explanatory sentence is defined as an expression of reflection on the events and phenomena of reality, with the position of the object-event accompanied by an indication of the reflection nature expressed by the governing predicate. General characteristics of this semantic type are given, as well as a number of semantic features serving as the basis for revealing the patterns of compatibility of various types of modus and dictum and the ways of their connection. It is proved that the previously existing qualification of relevance/factuality is based on overestimating the role of the brace and underestimating the predicative expression of deliberative. Several techniques are proposed to distinguish between thematic and factual utterances. Among sentence elements, the concept of the subject is the most significant for the typology of explanatory sentences, proposed to be divided into mono-subject and poly-subject ones. We note the poly-paradigmatic nature of the explanatory sentence and the presence of a number of its transformations used in the texts. The range of explanatory sentences with such an interpretation expands significantly without taking into account the boundaries of simple and complex sentences and some other constructive differences.

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Arteries of the antebrachium and manus of the tokay (Gekko gecko) (Reptilia: Gekkonidae)

Canadian Journal of Zoology ◽

10.1139/z81-085 ◽

1981 ◽

Vol 59 (4) ◽

pp. 573-582 ◽

Cited By ~ 5

Author(s):

Anthony P. Russell

Keyword(s):

Circulatory System ◽

Arterial System ◽

Functional Interpretation ◽

Gekko Gecko ◽

Low Viscosity ◽

Adhesive Pads ◽

The Subject ◽

First Time

The role of the circulatory system in the functioning of the subdigital adhesive pads of geckoes has been the subject of much discussion. However, the morphology and configuration of the blood system in the foot has remained poorly understood, rendering functional interpretation of the blood sinuses simplistic. Here the major arterial vessels of the manus are described for the first time and a discussion of their geometry is presented. Due to the paucity of information concerning the arterial system of the appendages of lizards a description of the major vessels of the antebrachium is also given.The data presented are based on the study of material injected with low-viscosity silicone rubber and then cleared so that vessels may be studied in situ. The data are pertinent to subsequent discussions of the microvasculature of the subdigital lamellae and of reconsiderations of their structure and form.

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Feline Morbillivirus Infection in Domestic Cats: What Have We Learned So Far?

Viruses ◽

10.3390/v13040683 ◽

2021 ◽

Vol 13 (4) ◽

pp. 683

Author(s):

Eliana De Luca ◽

Giuseppe Andrea Sautto ◽

Paolo Emidio Crisi ◽

Alessio Lorusso

Keyword(s):

Current Knowledge ◽

Domestic Cats ◽

Stray Cats ◽

Potential Association ◽

Clinicopathological Findings ◽

A Cell ◽

The Subject ◽

First Time

Feline morbillivirus (FeMV) was identified for the first time in stray cats in 2012 in Hong Kong and, since its discovery, it was reported in domestic cats worldwide. Although a potential association between FeMV infection and tubulointerstitial nephritis (TIN) has been suggested, this has not been proven, and the subject remains controversial. TIN is the most frequent histopathological finding in the context of feline chronic kidney disease (CKD), which is one of the major clinical pathologies in feline medicine. FeMV research has mainly focused on defining the epidemiology, the role of FeMV in the development of CKD, and its in vitro tropism, but the pathogenicity of FeMV is still not clear, partly due to its distinctive biological characteristics, as well as to a lack of a cell culture system for its rapid isolation. In this review, we summarize the current knowledge of FeMV infection, including genetic diversity of FeMV strains, epidemiology, pathogenicity, and clinicopathological findings observed in naturally infected cats.

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