644 research outputs found
Neoechinorhynchus (Hebesoma) personatus Tkach, Sarabeev et Shvetsova 2014, sp. n.
No full textNeoechinorhynchus (Hebesoma) personatus Tkach, Sarabeev et Shvetsova, sp. n. (fig. 12–18, table 3)Published as part of Tkach, Ie. V., Sarabeev, V. L. & Shvetsova, L. S., 2014, Taxonomic Status Of Neoechinorhynchus Agilis (Acanthocephala, Neoechinorhynchidae), With A Description Of Two New Species Of The Genus From The Atlantic And Pacific Mullets (Teleostei, Mugilidae), pp. 291-306 in Vestnik Zoologii 48 (4) on page 299, DOI: 10.2478/vzoo-2014-0035, http://zenodo.org/record/645318
HUMAN RESOURCE AS THE BASIS OF ECONOMIC SECURITY OF THE STATE
Get PDFThe work analyses the demographic and migration situation in Ukraine, predicted the possible consequences for the state as a result of such losses of the human resource as it is today, the dependence of the birth rate on the economic development of the country is shown. It is pointed out the lack of strategic planning in the state, which was supposed to ensure sustainable social and economic development of the state for decades. Migration programs for repatriation, simplification of procedures for obtaining citizenship and obtaining labor visas in such countries as Poland, Hungary, Turkey, Russia are considered. The main directions for combating the demographic crisis and population aging in Japan are given. On the example of China, it is shown that the main constituent of public success, both internal and external, is its population. Conclusions and recommendations are made aimed at preserving and restoring the human resource by the state
Neoastiotrema trituri Tkach 2008
No full textNeoastiotrema trituri (Grabda, 1959) Tkach, 2008 (Fig. 17) (Syn. Astiotrema trituri Grabda, 1959) Records. 1. Grabda (1959a, 1959b); 2. Sharpilo & Iskova (1989); 3. Tkach (2008). Remarks. Grabda (1959a) described A. trituri from the small intestine of the smooth, northern smooth or common newt, Lissotriton vulgaris (Linnaeus) (syn. Triturus vulgaris Dunn) (Caudata: Salamandridae), from Lake Mamry in northeastern Poland. Astiotrema trituri was distinguished from all Astiotrema species by (i) the position of the posterior testis near the posterior extremity of the body and posterior to the ends of the ceca, (ii) the much smaller cirrus pouch, and (iii) very large eggs – “almost double-sized” (48–61; 54 × 25–31; 29). That same year, Grabda (1959b) elucidated that A. trituri has life-cycle patterns identical to that of members of the Plagiorchioidea and concluded that the first intermediate host was a pulmonate snail, the great ramshorn, Planorbarius corneus (Linnaeus) (syn. Coretus corneus [Linnaeus]) (Gastropoda: Planorbidae). The second intermediate hosts included some cladoceran species: Simocephalus exspinosus (De Geer), Ceriodaphnia reticulata (Jurine), Daphnia magna Straus (Anomopoda: Daphniidae) and Eurycercus lamellatus (Müller) (Anomopoda: Eurycercidae). The development of this parasite includes the formation of a sporocyst and a xiphidiocercaria. Molecular characterization by Tkach (2008) of some taxa of Astiotrema including A. reniferum , A. monticellii (= P. monticellii), A. turneri (= H. turneri) and A. trituri demonstrated that the first three taxa formed a monophyletic clade closest to the heterophyids in contrast to A. trituri which clustered very close to Plagiorchis Lühe, 1899. Concerning A. trituri , it possesses a typical plagiorchiid-like bipartite seminal vesicle, whereas the other three species of Astiotrema (sensu lato) in the analysis of Tkach (2008) possess an undivided, sac-like seminal vesicle. Based on life-cycle patterns of A. monticellii (= P. monticellii) examined by Shevchenko & Vergun (1960), Tkach (2008) referred that: (i) the first intermediate host of A. monticellii (= P. monticellii) is the prosobranch (gilled) snail Bithynia leachii (Sheppard) (Gastropoda: Bithyniidae), not a pulmonate one as described for A. trituri; (ii) amphibians serve as the definitive host for A. trituri (see Grabda 1959b) whereas amphibians represent intermediate hosts for A. monticellii (= P. monticellii) (Shevchenko & Vergun 1960); and (iii) the development of A. monticellii (= P. monticellii) includes the formation of cercariae from the Pleurolophocerca group within rediae (see Shevchenko & Vergun 1960), which is typical for members of the Opisthorchioidea. As previous molecular phylogenetic analyses generally indicated that Astiotrema formed a monophyletic clade distinctly separate from all members of the Plagiorchioidea and that clade was, moreover, closer to the Opisthorchioidea (Tkach et al. 2001; Olson et al. 2003), Tkach (2008) removed A. trituri from Astiotrema and transferred it into the Plagiorchiidae. Despite the high similarity between A. trituri and members of Plagiorchis, the position of the right posterior testis (near the posterior extremity and past the cecal ends) vs the left anterior testis (intercecal and separated from right posterior testis by numerous uterine coils) gave justification for separating A. trituri into its own genus, Neoastiotrema, with its type- and only species, N. trituri (see Tkach 2008). Besprozvannykh et al. (2015) demonstrated that Shevchenko & Vergun (1960) most likely described a larva belonging to a member of the Opisthorchioidea and neither the cercaria nor the metacercaria of a species of Astiotrema. In addition, they clarified that the first intermediate host of A. odhneri is a pulmonate snail and not a prosobranch (gilled) one; whereas, the second intermediate host can include pulmonate snails, frog tadpoles, and small fish within which sporocysts and xiphidiocercariae develop, but neither rediae nor pleurolophocercariae form. Besprozvannykh et al. (2015, fig. 2) also demonstrated through 28S rRNA gene sequence data that Astiotrema species clustered away from the Plagiorchioidea and formed a monophyletic clade closer and in a basal position to the Opisthorchioidea. Thus, observations of life-cycle patterns by Besprozvannykh et al. (2015) point out a convergence between both Neoastiotrema and Astiotrema, whereas their phylogenetic results indicate a distant relationship between them. Accordingly, we conclude that: (1) reliance on life cycle patterns for differentiating between these two genera may not be useful; (2) without distinct morphological evidence, morphological data become more confusing and unconvincing for differentiating among morphologically similar taxa; hence, using molecular phylogenetic results and support may illustrate the degree of divergence or convergence and give an indicator for delimitations of species and/or higher ranks; (3) the bipartite vs unipartite nature of the seminal vesicle herein represents a stronger feature for differentiating between these two genera and it can be highly effective in differentiating at higher levels of taxonomy such as families or even superfamilies as stated by Pojmańska et al. (2008) and Tkach (2008).Published as part of Karar, Yasser F. M., Blend, Charles K., Dronen, Norman O. & Adel, Asmaa, 2023, Towards resolving the problematic status of the digenean genus Astiotrema Looss 1900: Taxa excluded from Astiotrema (sensu stricto) with special reference to plagiorchioid genera closely related to the restricted concept of Astiotrema, pp. 445-495 in Zootaxa 5284 (3) on pages 463-464, DOI: 10.11646/zootaxa.5284.3.2, http://zenodo.org/record/792950
Climate Arctic Governance: Perspectives on sub-national data-driven policymaking
No full textPresentation of the member of the University of Lapland team working in the WP7 - Pavel Tkach at Climate Arctic Governance conference in Copenhagen that took place on September 16, 2022, about aspects of Arctic regional climate governance information and knowledge about which the author took from his work in the Arctic PASSION project and subsequent communication with the policymakers
Mykhailo Tkach`s love songs
No full textСтаття присвячена аналізові текстів пісень М. Ткача на тему кохання. Детально розглядаються їхні мотиви, символічно-образна система та художні особливості. На цій основі простежується тісний зв’язок між індивідуальним авторським началом, поетикою народної пісні та традиціями української класичної поезії.Статья посвящена анализу текстов песен М. Ткача на тему любви. Подробно рассматриваются их мотивы, символично-образная система и художественные особенности. На этой основе прослеживается тесная связь между индивидуальным авторским началом, поэтикой народной песни и традициями украинской классической поэзии.This article analyzes Mykhailo Tkach`s love songs. Their motives, symbolic-imaginative system and artistic features are considered here. It was observed that there is a close connection between the author`s style, the poetics of folk song and the traditions of Ukrainian classical poetry
Rhabdias bakeri Tkach, Kuzmin et Pulis 2006
No full textRhabdias bakeri Tkach, Kuzmin et Pulis, 2006 (Fig. 15) Synonyms: Rhabdias ranae Walton, 1929 in Baker (1979). Host: Lithobates pipiens, L. sylvaticus (Amphibia: Anura: Ranidae). Site: lungs. Distribution: Northern Nearctic (northern U.S.A. and southern Canada). Description (after Tkach et al. 2006). Body 7.090 (4.051 –10.692) mm long, maximum width 245 (139–406) near vulva. Cuticular inflation less prominent in anterior part, from anterior end to level of distal part of oesophagus. In younger specimens, body cuticle evenly inflated along whole body. Oral opening oval, situated between 2 lateral pseudolabia. Each pseudolabium hemispherical in dorso-ventral view, rounded triangular in lateral view, with 2 small submedian protuberances (reduced submedian lips), each bearing a papilla. Vestibulum almost slit-like in apical view. Buccal capsule 17 (15–20) wide, 9 (7–12) deep, funnel-shaped in lateral view, round in apical view, with thick sclerotised walls. Lumen of buccal capsule narrow, cylindrical in lateral view. Anterior edge of buccal capsule slightly behind anterior edge of oesophagus. Oesophagus elongated, comparatively narrow, club-shaped, with dilated anterior muscular portion and egg-shaped posterior bulb. Oesophagus length 539 (465– 590), or 8.0 (5.4–11.9) % of body length. Width of oesophagus anterior end 36 (31–41), width of muscular dilation 43 (36–49), minimum width of glandular part 35 (27–44), width of oesophageal bulb 59 (48–72). Nerve ring encircling oesophagus posterior to its muscular dilation, at 174 (146–211) from oesophagus anterior end (32.3 [27.6–36.9] % of oesophagus length). Excretory pore opening just behind level of nerve ring. Intestine narrow at level of oesophageal-intestinal junction, then widening posteriorly. Rectum narrow, with thick sclerotised walls. Vulva postequatorial. Distance from anterior end to vulva 4.142 (2.297 –6.317) mm, or 58.7 (53.7–63.8) % of body length. Proximal ends of syngonia far overlapping at level of vulva. Egg size 50–61 × 94–113 (n = 19). Tail conical, elongated. Tail length 254 (193–336), or 3.7 (2.7–6.7) % of body length. Inflated body cuticle covering tail up to its tip in younger specimens; in older ones tail tip lacking inflated cuticle. Phasmids situated somewhat posterior to mid-length of tail. Remarks. The species is presumably a specific parasite of L. sylvaticus occasionally parasitizing other frogs (Tkach et al. 2006). Material studied: 33 specimens, including the type series (17 specimens, USNPC). References: Baker (1978), Tkach et al. (2006).Published as part of KUZMIN, YURIY, 2013, Review of Rhabdiasidae (Nematoda) from the Holarctic, pp. 1-76 in Zootaxa 3639 (1) on page 33, DOI: 10.11646/zootaxa.3639.1.1, http://zenodo.org/record/526262
Parapholis cylindrica – a nomenclatural correction
Get PDFRöser, M. & Tkach, N., 2020: Eine nomenklatorische Korrektur zu Parapholis cylindrica. Schlechtendalia 37: 27–29.
Vor kurzem wurde die neue Kombination Parapholis cylindrica veröffentlicht, allerdings ohne direkten Verweis auf das Basionym (Art. 41.5), so dass die neue Kombination nicht gültig ist. Dieses Defizit wird hier behoben, ergänzt durch eine Diskussion der Nomenklatur, Synonymie und Verwandtschaftsverhältnisse von Parapholis, der bisherigen Gattung Hainardia und anderen pooiden Gräsern mit ährigen oder traubigen Infloreszenzen.Röser, M. & Tkach, N., 2020: Parapholis cylindrica – a nomenclatural correction. Schlechtendalia 37: 27–29.
In a recent publication, the new combination Parapholis cylindrica has been proposed without direct reference to the basionym, so that this combination is invalid (Art. 41.5). This shortcoming is rectified and supplemented by a discussion of the nomenclature, synonymy and relationship of Parapholis, the previous genus Hainardia and other pooid grasses with spicate or raceme-like inflorescences.Die Schlechtendalia publiziert Originalbeiträge mit Schwerpunkt Spezielle Botanik und Biodiversität, Floristik, Mykologie/Lichenologie, Wissenschaftsgeschichte und andere Themen mit Bezug zu Botanischen Gärten und Herbarien
Taxonomic Status of Neoechinorhynchus agilis (Acanthocephala, Neoechinorhynchidae), with a Description of Two New Species of the Genus from the Atlantic and Pacifi c Mullets (Teleostei, Mugilidae)
Get PDFTkach Ie. V., Sarabeev V. L., Shvetsova L. S. Taxonomic Status of Neoechinorhynchus agilis (Acanthocephala, Neoechinorhynchidae), with a Description of Two New Species of the Genus from the Atlantic and Pacifi c Mullets (Teleostei, Mugilidae). Vestnik zoologii. 2014. № 48(4). P. 291–306.EN : Taxonomic Status of Neoechinorhynchus agilis (Acanthocephala, Neoechinorhynchidae), with a De-
scription of Two New Species of the Genus from the Atlantic and Pacifi c Mullets (Teleostei, Mugili-
dae). Tkach, Ie. V., Sarabeev, V. L., Shvetsova, L. S. — Th e wide variability in morphological features,
geographical and host ranges of mullet acanthocephalan parasite Neoechinorhynchus agilis
(Rudolphi, 1819), raises the question of taxonomic status of this species. Rudolphi’s type and Yamaguti`s voucher specimens, as well as our own material from the WW Pacifi c and NE Atlantic region were used herein to provide comparative morphological analysis. The study revealed three different species of
Neoechino-rhynchus, N. (N.) agilis and N.(H.) personatus Tkach, Sarabeev et Shvetsova, sp. n. in the Atlantic and N. (H.) yamagutii Tkach, Sarabeev et Shvetsova, sp. n. in the Pacific. Strong morphological and morpho-metric differences were found between three described herein species from different hosts and regions.
The dividing of N. agilis into three species, two of them are new, provides a basis for the further revision
of host-geographical records of mullet acanthocephalan parasite
Molecular Data Confirm The Species Status Of Neoechinorhynchus Personatus And N. Yamagutii (Acanthocephala, Neoechinorhynchidae) From The Atlantic And Pacific Grey Mullets (Teleostei, Mugilidae)
No full textSarabeev, Volodimir, Tkach, Ie., Sueiro, R. A., Leiro, J. (2020): Molecular Data Confirm The Species Status Of Neoechinorhynchus Personatus And N. Yamagutii (Acanthocephala, Neoechinorhynchidae) From The Atlantic And Pacific Grey Mullets (Teleostei, Mugilidae). Zoodiversity 54 (1): 1-10, DOI: 10.15407/zoo2020.01.001, URL: http://dx.doi.org/10.15407/zoo2020.01.00
Таксономический статус Neoechinorhynchus agilis (Acanthocephala, Neoechinorhynchidae), с описанием двух новых видов рода от кефалевых рыб (Teleostei, Mugilidae) Атлантики и Пацифики
Get PDFШирокое географическое распространение, богатый список хозяев, а также значительная вариабельность метрических признаков акантоцефалы Neoechinorhynchus agilis (Rudolphi, 1819) ставит вопрос о таксономическом статусе этого вида. Для проведения сравнительного морфологического анализа был использован типичный материал Рудольфи и ваучерные экземпляры Ямагути, а также собственный материал, собранный в западной части Тихого океана и северо-восточной Атлантике. В результате исследования было обнаружено три вида акантоцефал Neoechinorhynchus, в том числе два вида из Атлантики: N. (N.) agilis и N. (H.) personatus Tkach, Sarabeev et Shvetsova, sp. n., и один вид из Тихого океана, N. (H.) yamagutii Tkach, Sarabeev et Shvetsova, sp. n. Описанные в работе виды хорошо различаются как морфологически, так и метрически. Разделение N. agilis на три вида, два из которых описаны впервые, является основой для дальнейшего пересмотра находок этой акантоцефалы из разных регионов и от разных хозяев.The wide variability in morphological features, geographical and host ranges of mullet acanthocephalan parasite Neoechinorhynchus agilis (Rudolphi, 1819), raises the question of taxonomic status of this species. Rudolphi’s type and Yamaguti`s voucher specimens, as well as our own material from the WW Pacific and NE Atlantic region were used herein to provide comparative morphological analysis. The study revealed three different species of Neoechinorhynchus, N. (N.) agilis and N. (H.) personatus Tkach, Sarabeev et Shvetsova, sp. n. in the Atlantic and N. (H.) yamagutii Tkach, Sarabeev et Shvetsova, sp. n. in the Pacific. Strong morphological and morphometric differences were found between three described herein species from different hosts and regions. The dividing of N. agilis into three species, two of them are new, provides a basis for the further revision of host-geographical records of mullet acanthocephalan parasites
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