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382. A new hyperapolytic species, Trilocularia eberti sp. n. (Cestoda: Tetraphyllidea), from Squalus cf. mitsukurii (Squaliformes: Squalidae) off South Africa with comments on its development and fecundity
- Creator:
- Pickering, Maria and Caira, Janine N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- tapeworms, taxonomy, growth, life history, sharks, and parasites
- Language:
- English
- Description:
- A new species of tetraphyllidean cestode in the genus Trilocularia is described from an undescribed shark species, Squalus cf. mitsukurii, off the coast of South Africa. Trilocularia eberti sp. n. is the second known member of its genus, and like its congener, T. gracilis (Olsson, 1866-1867) Olsson, 1869, is extremely hyperapolytic, dropping proglottids from its strobila while they are still very immature. Characteristic of the genus, it possesses a distinctive scolex with triloculated bothridia, but differs conspicuously from its congener in its possession of an anterior loculus that is much larger in width relative to the paired posterior loculi, and also in its possession of an anterior, enlarged region of its free proglottids that is triangular with a slit-like ventral aperture, rather than rounded and cup-like. This anterior region of the free proglottid is used in attachment, and its development is described. For assessment of fecundity, an attempt was made to record all free proglottids of all ages found in both host individuals, and yielded an average estimate of 362 free proglottids being produced per individual worm of T. eberti sp. n. Both Trilocularia species parasitize sharks of the genus Squalus, and given the host specificity typically exhibited by tetraphyllideans and preliminary examinations of other members of this shark genus, it is likely that other Squalus species will be found to host additional new Trilocularia species.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
383. A new method of assembling large magnetic blocks from permanent NdFeB magnets
- Creator:
- Žežulka, Václav and Pavel Straka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, magnetické obvody, magnetic circuits, magnet assembly, magnetic separation, magnetic filtration, permanent magnets, NdFeB magnets, large magnetic blocks, 7, and 551
- Language:
- English
- Description:
- The presented technological procedure makes it possible to assemble large magnetic blocks from permanent magnets with a high value of maximum energy product in such a way that the individual magnets or magnetic plates are moved toward each other at a controlled speed in the direction perpendicular to the future common contact surface of these magnets, i.e. parallel to the induction lines crossing this contact surface. Unlike in the previously used way of assembling the blocks, it is thus possible to eliminate the influence of partial demagnetization as the blocks are being assembled and consequently to reach higher values of magnetic induction in the air gap of the magnetic circuit. When applying the new method of assembling the blocks for instance in circuits of magnetic filters for the purification of ceramic suspensions, a prerequisite for the further improvement of the technological parameters of filtration is thus created., Václav Žežulka and Pavel Straka., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
384. A new model for relationship between irradiance and the rate of photosynthesis in Oryza sativa
- Creator:
- Ye, Z.-P.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- apparent quantum yield, compensation irradiance, intrinsic quantum yield, and saturation irradiance
- Language:
- Multiple languages
- Description:
- The calculated maximum net photosynthetic rate (PN) at saturation irradiance (I m) of 1 314.13 µmol m-2 s-1 was 25.49 µmol(CO2) m-2 s-1, and intrinsic quantum yield at zero irradiance was 0.103. The results fitted by nonrectangular hyperbolic model, rectangular hyperbolic method, binomial regression method, and the new model were compared. The maximum PN values calculated by nonrectangular hyperbolic model and rectangular hyperbolic model were higher than the measured values, and the I m calculated by nonrectangular hyperbolic model and rectangular hyperbolic model were less than measured values. Results fitted by new model showed that the response curve of PN to I was nonlinear at low I for Oryza sativa, PN increased nonlinearly with I below saturation value. Above this value, PN decreased nonlinearly with I.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
385. A new monorchiid cercaria (Digenea) parasitising the purple clam Amiantis purpurata (Bivalvia: Veneridae) in the Southwest Atlantic Ocean, with notes on its gonadal effect
- Creator:
- Cremonte, Florencia, Kroeck, Marina Andrea, and Martorelli, Sergio Roberto
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Digenea, Monorchiidae, cercaria, metacercaria, Bivalvia, Veneridae, and Argentine Sea
- Language:
- English
- Description:
- An unnamed microcercous cercaria (Digenea: Monorchiidae), a parasite of Amiantis purpurata (Lamarck, 1818) (Bivalvia: Veneridae) and its corresponding metacercaria from the province of Buenos Aires and the Patagonian coast of the Southwest Atlantic Ocean, are described. The cercaria described in this paper differs from the three other monorchiid microcercous cercariae, i.e., Lasiotocus minutus (Manter, 1931), Lasiotocus elongatus (Manter, 1931), and Cercaria caribbea XXXVI Cable, 1956, mainly because of the extension of the excretory vesicle and the location of the ventral sucker. Cercariae artificially extracted from sporocysts encyst in a dish and form metacercariae enveloped by a gelatinous sac with two prolongations, which are used to adhere to the substratum. The monorchiid described in this paper has a life cycle similar to those of L. minutus and L. elongatus, although the adult stage of the present species is still unknown. Their larvae are similar in morphology and have venerid clams as their first hosts. The presence of a monorchiid larva is reported for the first time in the Southern Hemisphere. Its monthly prevalence rates, ranging from 0 to 25% (mean: 8.3%), are given from the Patagonian coast. The infection seems to cause castration as it was observed that during March through to May, when most gametes were produced in uninfected individuals, 81% of the infected individuals did not produce gametes.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
386. A new overlapping community detection algorithm based on similarity of neighbors in complex networks
- Creator:
- Çetin, Pelin and Amrahov, Şahin Emrah
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- overlapping community detection, complex networks, graph approach, similarity approach, and community metrics
- Language:
- English
- Description:
- Community detection algorithms help us improve the management of complex networks and provide a clean sight of them. We can encounter complex networks in various fields such as social media, bioinformatics, recommendation systems, and search engines. As the definition of the community changes based on the problem considered, there is no algorithm that works universally for all kinds of data and network structures. Communities can be disjointed such that each member is in at most one community or overlapping such that every member is in at least one community. In this study, we examine the problem of finding overlapping communities in complex networks and propose a new algorithm based on the similarity of neighbors. This algorithm runs in O(mlgm) running time in the complex network containing m number of relationships. To compare our algorithm with existing ones, we select the most successful four algorithms from the Community Detection library (CDlib) by eliminating the algorithms that require prior knowledge, are unstable, and are time-consuming. We evaluate the successes of the proposed algorithm and the selected algorithms using various known metrics such as modularity, F-score, and Normalized Mutual Information. In addition, we adapt the coverage metric defined for disjoint communities to overlapping communities and also make comparisons with this metric. We also test all of the algorithms on small graphs of real communities. The experimental results show that the proposed algorithm is successful in finding overlapping communities.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
387. A new species of Acanthochondria (Copepoda: Chondracanthidae) parasitizing the flounder Xystreurys rasile (Pleuronectiformes: Paralichthyidae) from Argentina
- Creator:
- Alarcos, Ana Julia and Timi, Juan Tomás
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- parasitic copepod, Acanthochondria sagitta, flounder, Xystreurys rasile, and Argentina
- Language:
- English
- Description:
- A new copepod species, Acanthochondria sagitta sp. n., is described based on specimens collected from the flounder Xystreurys rasile (Jordan) (Pleuronectiformes, Paralichthyidae), caught in the coastal waters off Necochea, Buenos Aires Province, Argentina. The new species differs from its congeners by the following combination of characters: presence of three pairs of cephalic outgrowths; the triangular shape of the trunk with diverging postero-lateral processes; leg 2 of an intermediate shape between Types C and D, which projects laterally from the trunk, and Type B-V antennule bearing two proximal processes (one ventral and one dorsal) on the swollen basal portion.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
388. A new species of Anchistrotos (Copepoda: Taeniacanthidae) from hilsa shad, Tenualosa ilisha (Actinopterygii: Clupeidae), off Iraq
- Creator:
- Maran, B. A. Venmathi, Moon, Seong Yong, and Adday, Thamir Katea
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- taxonomy, fish, parasite, gills, Anchistrotos, maxilliped, and whip-like setae
- Language:
- English
- Description:
- A new species of parasitic copepod Anchistrotos tangi sp. n. (Cyclopoida: Taeniacanthidae) is described based on adult female specimens collected from the gills of hilsa shad, Tenualosa ilisha (Hamilton, 1822) (Actinopterygii: Clupeidae) captured off Iraq. The new species differs from its congeners by having the following combination of characters in the adult female: 1) the rostral area sclerotised; 2) the presence of row of spinules on the proximal and distal margins of the anal somite; 3) the maxilliped claw with 2 long whip-like setae just crossing the distal edge of claw with serrated terminal margin; and 4) the leg 5 ornamented with patched spinules distally. This is the ninth nominal species of Anchistrotos Brian, 1906.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
389. A new species of Australotaenia (Cestoda: Proteocephalidea) from a snake in Cambodia: host switching or postcyclic parasitism in a distant region?
- Creator:
- Chambrier, Alain de and Scholz, Tomáš
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- taxonomy, zoogeography, tapeworms, helminths, Reptilia, South East Asia, and Indomalayan Region
- Language:
- English
- Description:
- Australotaenia de Chambrier et de Chambrier, 2010 has been proposed to accommodate two species of proteocephalidean cestodes from hylid frogs (Litoria spp.) in Australia. Recently, apparently congeneric cestode, for which the name A. bunthangi sp. n. is proposed, was found in the homalopsid snake Enhydris enhydris (Schneider) (Serpentes: Homalopsidae) from South-East Asia (Cambodia). This finding indicates a much wider range of definitive hosts of species of this genus, i.e. amphibians and reptiles, which is exceptional among proteocephalideans. Postcyclic parasitism, i.e. predation of the definitive host infected with sexually mature parasites, cannot be excluded but does not seem to be probable. In addition, the occurrence of A. bunthangi in the former Indochina extends the range of the geographical distribution of the genus to another zoogeographical region. The new species differs from both species of Australotaenia in the relative size of an apical organ, the diameter of which equals to that of suckers (versus much smaller in the remaining species, in which the width of the apical organ represents less than 2/3 of the diameter of the suckers), much smaller scolex and suckers (width 150 μm and diameter of suckers 50-55 μm versus 245-420 μm and 100-140 μm, respectively), and longer body (224 mm versus 57-121 mm). In addition, A. bunthangi differs from A. hylae (Johnston, 1912) (type-species of the genus) by the number of testes (46-64 versus 74-106 in A. hylae) and by the ovary width/proglottis width ratio (55-65% versus 68-71% in A. hylae). Australotaenia bunthangi differs from A. grobeli de Chambrier et de Chambrier, 2010 by relative size of the cirrus-sac (its length represents 18-24% of the width of the proglottis versus 27-33% in A. grobeli) and by the diameter of the embryophore (25-27 µm versus 18-23 µm in A. grobeli).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
390. A new species of Choleoeimeria (Apicomplexa: Eimeriidae) from Oustalet's chameleon, Furcifer oustaleti (Sauria: Chamaeleonidae)
- Creator:
- McAllister, Chris T.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Coccidia, Choleoeimeria, Furcifer oustaleti, Oustalet's chameleon, and taxonomy
- Language:
- English
- Description:
- One of three (33%) captive specimens of Oustalet's chameleon, Furcifer oustaleti (Mocquard) originally from Madagascar and housed at the Oklahoma City Zoological Park Herpetarium, Oklahoma County, Oklahoma, USA, was found to be passing an undescribed species of Choleoeimeria in its faeces. Oocysts of Choleoeimeria fischeri sp. n. were cylindroidal, 30.3 × 16.8 (28-34 × 15-18) µm, with a smooth, bilayered wall and a length/width ratio (L/W) of 1.8. A micropyle and oocyst residuum was absent but a fragmented polar granule was often present. Sporocysts were ovoidal, 9.6 × 8.0 (9-10 × 7-9) µm, with an L/W of 1.2. Stieda, sub-Stieda, and para-Stieda bodies were absent. The sporocyst residuum consists of large globules dispersed between sporozoites. Sporozoites were elongate, 8.6 × 2.9 (8-10 × 2-3) µm, with an elongate posterior refractile body. The new species represents the second coccidian described from this lizard.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public