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In the present review, we summarised the information on helminths of 14 species of wild carnivorans (a total of 260 individuals examined) from Ukraine based on an investigation of collection materials. Additionally, helminths of the domestic dog, Canis familiaris L. (n = 73) and domestic cat, Felis catus L. (n = 11) were reviewed. Helminth species and main helminth taxa (Cestoda, Trematoda, and Nematoda) were classified according to their occurrence (prevalence of infection). Helminth fauna composition and structure in host families Canidae, Felidae, and Mustelidae and in separate host species were analysed. Sixty helminth species were found in wild carnivorans in Ukraine, including 18 species of cestodes, 11 species of trematodes, and 31 species of nematodes. In wild Canidae, 45 helminth species were recorded. Nematodes were a predominating group of helminths in the red fox, Vulpes vulpes L., cestodes predominated in the wolf, Canis lupus L., and trematodes occurred more often in the raccoon dog, Nyctereutes procyonoides Gray. Mustelidae (40 specimens of 8 species) harboured 25 helminth species; nematodes predominated by their occurrence and number of species. In the American mink, Neovizon vison Brisson, however, trematodes appeared to be the predominating group of helminths. The wolf, the red fox, and the domestic dog showed maximum similarity in the helminth fauna composition. A rather high similarity was observed between the helminth faunae of the raccoon dog and the American mink (IS = 0.42), both hosts being introduced species in the fauna of Ukraine. [ABSTRACT FROM AUTHOR]

Helminths of 12 fish species collected near the South Orkney Islands, West Antarctica were studied. In the whole sample of 115 fish specimens, we identified one species of Monogenea, 5 species of Trematoda, 4 species of Cestoda, 5 species of Nematoda, and 7 species of Acanthocephala. All cestode species, 3 species of nematodes, and 5 species of acanthocephalans were represented only by larval stages; fish are definitive hosts for the remaining 10 helminth species. Details of composition and structure of helminth communities were studied in 3 fish species: Chaenocephalus aceratus (Lönnberg, 1906), Champsocephalus gunnari Lönnberg, 1905, and Pseudochaenichthys georgianus Norman, 1937, each represented by more than 20 specimens in a sample. In these hosts, 19, 8, and 16 helminth species were found, correspondingly. In the helminth communities of C. aceratus and P. georgianus, the highest values of the infection prevalence and abundance were recorded for larval cestodes (Diphyllobothrium sp., Tetrabothriidea), nematodes (Pseudoterranova sp., Contracaecum sp.), acanthocephalans (Corynosoma spp.), as well as adults of the trematode Neolebouria georgiensis Gibson, 1976. The same trematode species and larval cestodes predominated in the helminth community of C. gunnari. All recorded species of parasites are generalists, each known from a range of fish hosts in Antarctica. [ABSTRACT FROM AUTHOR]

Theoretical calculations of the electronic structure and measurements of optical properties of the Heusler alloy Mn1.5Fe1.5Al have been performed. The density functional theory based optimized β-Mn-type crystal structure is reported for the first time for Mn1.5Fe1.5Al. An anomalous for metals behavior of the optical conductivity of the alloy in the infrared (IR) spectral region was found, i.e., the absence of the Drude rise and a high level of interband absorption. Such features of the optical spectrum indicate a complex structure of the band spectrum and a high density of states in the vicinity and at the Fermi level. The features on the optical conductivity curve are related to certain interband electron transitions. [ABSTRACT FROM AUTHOR]

Monitoring studies of the species diversity in marine ecosystems provide important data on ecological changes caused by global warming and anthropogenic influence. The present work was aimed to analyze the species diversity of the helminths parasitic in teleost fishes inhabiting the area near the Ukrainian Antarctic Station "Akademik Vernadsky" (Galindez Island, Argentine Islands, West Antarctica). During April-January of 2014-2015 and 2019-2020, 156 specimens of six fish species (Notothenia coriiceps, N. rossii, Chaenocephalus aceratus, Parachaenichthys charcoti, Trematomus bernacchii, and Harpagifer antarcticus) were examined. Totally, 21,166 specimens of 31 helminth species were collected and assigned to five taxonomic groups: Monogenea (1 species), Digenea (10), Nematoda (5), Cestoda (4), and Acanthocephala (11). Twenty-six helminth species were found in N. coriiceps, 14 in N. rossii, 27 in P. charcoti, 23 in Ch. aceratus, 16 in T. bernacchii, and six in H. antarcticus. Larval stages of anisakid nematodes prevailed in the helminth community of Ch. aceratus (66 %) and P. charcoti (40 %), while other fish species were mostly infected with acanthocephalans, trematodes and cestodes. The present data on the species diversity of helminth communities can be used as a baseline for long-term monitoring studies of fish parasites in the region of the Argentine Islands. [ABSTRACT FROM AUTHOR]

Ellipsometric studies of the optical properties of the intermetallic Cr80Al20 compound in the spectral range of 0.22-15 μm have been performed. The self-consistent calculation of the electronic structure and density of the electronic states of the material has been carried out. The spectrum of interband light absorption is interpreted on the basis of comparative analysis of theoretical and experimental dispersion dependences of optical conductivity. A number of characteristics of conduction electrons have been determined. [ABSTRACT FROM AUTHOR]

Five specimens of a parasitic nematode Dicheilonema ciconiae (Schrank, 1788) were collected from black stork, Ciconia nigra Linnaeus, in Kyiv Zoological Park. Identification of the nematodes was confirmed by morphological examination of the specimens collected. Th e ornamentation of the body cuticle in caudal region of males (area rugosa) is fi rst described in D. ciconiae. [ABSTRACT FROM AUTHOR]