Regenerating aggregates of hydra display unique cytoskeletal organisation that is absent in a regeneration-deficient strain

Hydra has the unique ability to regenerate from aggregates of dissociated single cells that lack positional information. We compared two strains of hydra, a strain of hydra that was capable of regenerating from aggregates and a strain of hydra that was deficient in this type of regeneration. We observed unique actin cytoskeletal arrangements that were present in the regenerates of regeneration-competent strain but not in the regeneration-deficient strain. Concomitantly, the regeneration-deficient strain failed to organise the extracellular cytoskeleton of laminin and collagen between ectodermal and endodermal epithelial cells. These interesting preliminary observations highlight the importance of the cytoskeletal organisation in regeneration of hydra and suggest that regeneration from the aggregates of dissociated cells through de novo patterning requires correct structural organisation of cytoskeletal elements.

The geometry of artistic space in the works by Valentin Louis Georges Eugène Marcel Proust

The article considers the peculiarities of the artistic system in the works by the French writer of the turn of the 19th–20th centuries, VLGE Marcel Proust. The foundations of his aesthetic views, which are manifested primarily at the level of the structural organisation in the novel cycle “In Search of Lost Timeˮ are studied. The specificity of the narrative, where the main role is played by involuntary memory, allows us to speak about the special geometry of the artistic space in this work. It happens due to Proust's rejection of “plane psychologyˮ in favour of “psychology in time”. It is shown how on such a basis, thanks to the mnemonic mechanism, a complex connection of spontaneously arising spatial fragments with the temporal moments of existence arises and the chronotopic structure of the novel, built on the principle of relativity, is constructed where time becomes, in fact, the fourth dimension of space.

Notion of an accent in linguistic studies

The given article introduces the main areas of studying an accent. Particular attention is given to the field of linguistics, phonetics, and phonological research where an accent is not only a characteristic of an individual but also a bearer of distinctive features of the foreign speech. These features include differences on various language levels such as phonological, morphological, lexical, syntactical. The linguistic and non-linguistic phonetic features are illustrated. The peculiarities in pronunciation, which include melodic arrangements of utterances, rhythmical and structural organisation of the sentence, pausation, articulations in addition to vowels' and consonants' production and their interaction in speech are described as related to linguistic features. Non-linguistic features are connected with the personality of a speaker, the listener, the situation of speech and the context. The article presents a short outline of the criteria to measure a foreign-accented speech.

Cultural types and the perception of current environmental risks by local communities of the Baltic Sea region

This work presents findings from research into the relationship between the structural organisation and cultural attitudes of local communities in the Baltic Sea region and the way they perceive environmental risks. The response of the Kaliningrad community to the development of a local potassium and magnesium salt mine is used as an illustration. The article deals with how local communities perceive the image of risks formed and reproduced via various communication channels. The structural context and the context of communication are taken into account. Another focus is on how this perception is affected by the type of community members’ cultural attitudes (according to Mary Douglas’s grid/group model). The space of categorical variables obtained through multiple correspondence analysis (MCA) aids in clustering the cases (respondents) as well as in testing theoretical assumptions for compliance with the findings. The communicative practices characteristic of all the clusters (classes of cases) are examined; the relationship between the structural organisation of groups, their cultural attitudes, their perception of environmental risks, and the performance of environmental agencies are explored. An evaluation of the comparative efficiency of different ways and means of risk communication with the identified groups is made. It is concluded that the proposed model is methodologically promising and there is a need for differentiated risk-communication strategies.

Extracellular matrix and wall composition are diverse in the organogenic and non-organogenic calli of Actinidia arguta

Key message Differences in the composition and the structural organisation of the extracellular matrix correlate with the morphogenic competence of the callus tissue that originated from the isolated endosperm of kiwifruit. Abstract The chemical composition and structural organisation of the extracellular matrix, including the cell wall and the layer on its surface, may correspond with the morphogenic competence of a tissue. In the presented study, this relationship was found in the callus tissue that had been differentiated from the isolated endosperm of the kiwiberry, Actinidia arguta. The experimental system was based on callus samples of exactly the same age that had originated from an isolated endosperm but were cultured under controlled conditions promoting either an organogenic or a non-organogenic pathway. The analyses which were performed using bright field, fluorescence and scanning electron microscopy techniques showed significant differences between the two types of calli. The organogenic tissue was compact and the outer walls of the peripheral cells were covered with granular structures. The non-organogenic tissue was composed of loosely attached cells, which were connected via a net-like structure. The extracellular matrices from both the non- and organogenic tissues were abundant in pectic homogalacturonan and extensins (LM19, LM20, JIM11, JIM12 and JIM20 epitopes), but the epitopes that are characteristic for rhamnogalacturonan I (LM5 and LM6), hemicellulose (LM25) and the arabinogalactan protein (LM2) were detected only in the non-organogenic callus. Moreover, we report the epitopes, which presence is characteristic for the Actinidia endosperm (LM21 and LM25, heteromannan and xyloglucan) and for the endosperm-derived cells that undergo dedifferentiation (loss of LM21 and LM25; appearance or increase in the content of LM5, LM6, LM19, JIM11, JIM12, JIM20, JIM8 and JIM16 epitopes).

Accelerating the electrical response of solvent-dispersed imogolite nanotubes through structural organisation

Structural organisation of solvent-dispersed imogolite nanotubes accelerated their electrical response, resulting in birefringence variations analogous to a liquid crystal system.