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602. A redescription of Arostrilepis horrida (Linstow, 1901) and descriptions of two new species from Palaearctic microtine rodents, Arostrilepis macrocirrosa sp. n. and A. tenuicirrosa sp. n. (Cestoda: Hymenolepididae)
- Creator:
- Makarikov, Arseny A., Gulyaev, Vladimir D., and Kontrimavichus, Vytautas L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Cestoda, Hymenolepididae, Arostrilepis horrida, redescription, Arostrilepis macrocirrosa, Arostrilepis tenuicirrosa, new species, morphology, and microtine rodents
- Language:
- English
- Description:
- The type species of the cestode genus Arostrilepis Mas-Coma et Tenora, 1997, Arostrilepis horrida (Linstow, 1901), is redescribed on the basis of the syntype material from the brown rat (Rattus norvegicus) deposited in the collection of the Museum für Naturkunde, Berlin. Arostrilepis horrida (sensu lato), reported from a wide range of rodents throughout the Holarctic Region, is shown to be a species complex. The proposed host range and geographical distribution of A. horrida (sensu stricto) are limited to the data reported in the original description. The previously proposed synonymy of A. horrida is examined and the following species are excluded from the list of its synonyms: Hymenolepis procera Janicki, 1904, H. arvicolina Cholodkowsky, 1913, H. sciurina Cholodkowsky, 1913 and H. mathevossianae Akhumyan, 1946; these are considered species inquirendae. Specimens previously identified as A. horrida from voles from the Asian part of Russia are revised and newly collected materials are worked out. Two new species, A. macrocirrosa sp. n. and A. tenuicirrosa sp. n., are described. The main differentiating characters used to distinguish Arostrilepis spp. are the form and size of cirrus and its armature as well as the type of arrangement for the testes. The new species can also be distinguished from one another on the basis of sequences of the ITS2 rRNA gene. The generic diagnosis of Arostrilepis is emended. Hymenolepis neurotrichi Rausch, 1962, which had been placed in Arostrilepis by Mas-Coma and Tenora (1997), does not correspond to the generic diagnosis and is considered a species incertae sedis.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
603. A redescription of Haemogregarina fitzsimonsi Dias, 1953 and some comments on Haemogregarina parvula Dias, 1953 (Adeleorina: Haemogregarinidae) from southern African tortoises (Cryptodira: Testudinidae), with new host data and distribution records
- Creator:
- Cook, Courtney A., Smit, Nico J., and Davies, Angela J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- blood parasites, haemogregarines, Haemogregarina fitzsimonsi, Haemogregarina parvula, tortoises, Chersina angulata, Kinixys spp., Stigmochelys pardalis, and Africa
- Language:
- English
- Description:
- Blood films were examined from 154 wild and captive tortoises from four provinces of South Africa, including Gauteng, Kwazulu-Natal, North West and Western Cape. The five species of chelonians studied were Chersina angulata (Schweigger), Kinixys belliana belliana (Gray), K. lobatsiana Power, K. natalensis Hewitt, and Stigmochelys pardalis (Bell). Two species of haemogregarines, previously reported from Mozambique, were identified in blood films, namely Haemogregarina fitzsimonsi Dias, 1953 and Haemogregarina parvula Dias, 1953. Additional stages of development (trophozoites and probable meronts, merozoites and immature gamonts) in blood preparations from South Africa warranted the redescription of H. fitzsimonsi. A variety of hosts and broad host distribution range were observed for this haemogregarine, with all five species of tortoises parasitized, wild and captive, from all four provinces, in all seasons. In contrast, only two individuals of K. b. belliana and one S. pardalis, all three captive in Kwazulu-Natal, contained H. parvula with encapsulated stages resembling those of Hemolivia mauritanica (Sergent et Sergent, 1904). For H. fitzsimonsi, parasite prevalences, but not parasitaemias, were significantly higher in captive than wild S. pardalis; captive female S. pardalis also showed a significantly greater prevalence of infection than males, but younger, lighter hosts were not significantly more heavily parasitized than older, heavier individuals. The ticks, Amblyomma marmoreum Koch, 1844 and A. sylvaticum (De Geer, 1778), found attached to some tortoises, may prove to be definitive hosts for the two species of haemogregarines observed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
604. A redescription of Pseudocharopinus pteromylaei Raibaut et Essafi, 1979 (Siphonostomatoida: Lernaeopodidae) collected from the South African east coast
- Creator:
- Dippenaar, Susan M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Pseudocharopinus, meso-parasitic copepod, bull ray, and South Africa
- Language:
- English
- Description:
- Pseudocharopinus Kabata, 1964 is one of the 48 genera comprising the Lernaeopodidae (Copepoda, Siphonostomatoida). Currently there are 11 accepted species contained in Pseudocharopinus. Pseudocharopinus pteromylaei Raibaut et Essafi, 1979 infects the spiracles and gill filaments of Pteromylaeus bovinus (Geoffroy St. Hilaire) and is most similar in general appearance to P. pteroplateae (Yamaguti et Yamasu, 1959) from which it clearly differs in the size and dimensions of the dorsal shield and the posterior processes. Additional features of the antenna and the maxilliped of P. pteromylaei, not previously illustrated, are discussed and illustrated while more detailed illustrations of other appendages are provided. This is the first report of the occurrence of a Pseudocharopinus species from the west Indian Ocean and the first report of P. pteromylaei off the east coast of South Africa.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
605. A redescription of Trichosurolaelaps dixous Domrow, 1972 (Acari: Laelapidae), from Trichosurus cunninghami (Marsupialia: Phalangeridae) from southern Australia
- Creator:
- Hufschmid, Jasmin, Beveridge, Ian, Handasyde, Kathrine Ann, and Spratt, David Michael
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Trichosurolaelaps dixous, Trichosurolaelaps crassipes, Trichosurus cunninghami, Trichosurus vulpecula, ectoparasites, Acari, and Laelapidae
- Language:
- English
- Description:
- The adults of Trichosurolaelaps dixous Domrow, 1972 are redescribed from a population of Trichosurus cunninghami Lindenmayer, Dubach et Viggers, 2002 in south-eastern Australia. The nymphal stages are described for the first time. Morphologically, T. dixous is similar to Trichosurolaelaps crassipes Womersley, 1956. Morphological differences between the pre-female deutonymphs and adult females of the two mite species are the presence of a single large ventral spur on tibia I of T. dixous. Males of T. dixous could not be distinguished from T. crassipes morphologically and the idiosomal length of male T. dixous was variable (475-683 μm). Protonymphs of the two mite species differed only in size, with that of T. dixous being larger. Although T. crassipes was prevalent in a sympatric population of Trichosurus vulpecula and has been reported from other populations of T. cunninghami in southern Australia, it was never recovered from the population of T. cunninghami studied.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
606. A refinement of the radial Pohozaev identity
- Creator:
- Catrina, Florin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Green's function, positive solutions, and supercritical nonlinearity
- Language:
- English
- Description:
- In this article we produce a refined version of the classical Pohozaev identity in the radial setting. The refined identity is then compared to the original, and possible applications are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
607. A reinvestigation of spermiogenesis in Amphilina foliacea (Platyhelminthes: Amphilinidea)
- Creator:
- Bruňanská, Magdaléna, Poddubnaya, Larisa G., and Xylander, Willi E. R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- ultrastructure, testes, spermiogenesis, Amphilina foliacea, Amphilinidea, Cestoda, and Platyhelminthes
- Language:
- English
- Description:
- Spermiogenesis in the amphilinidean cestode Amphilina foliacea (Rudolphi, 1819) was examined using transmission electron microscopy. The orthogonal development of the two flagella is followed by a flagellar rotation and their proximodistal fusion with the median cytoplasmic process. This process is accompanied by extension of both the mitochondrion and nucleus into the median cytoplasmic process. The two pairs of electron-dense attachment zones mark the lines where the proximodistal fusion of the median cytoplasmic process with the two flagella takes place. The intercentriolar body, previously undetermined in A. foliacea, is composed of three electron-dense and two electron-lucent plates. Also new for this species is the finding of electron-dense material in the apical region of the differentiation zone at the early stage of spermiogenesis, and the fact that two arching membranes appear at the base of the differentiation zone only when the two flagella rotate towards the median cytoplasmic process. The present data add more evidence for a close relationship between the Amphilinidea and the Eucestoda.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
608. A related-key attack on iterated chaotic ciphers
- Creator:
- Yang, Yang and Jin, Chenhui
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chaotic cipher, related-key attack, ZLL chaotic cipher, divide-and-conquer attack, and known plaintexts attack
- Language:
- English
- Description:
- In this paper, we present a new type of attack on iterated chaotic ciphers using related keys. Based on the fact that a chaotic sequence is not sensitive to the less significant bits of initial conditions and parameters, a divide-and-conquer attack on iterated chaotic ciphers was presented by us before, which significantly reduces the computing complexity of attacks. However, if the information leaked is significant according to the distribution of the coincidence degrees, a measure for the information leakage of chaotic ciphers, or the size of the key is large, then it is difficult for the divide-and-conquer attack to reduce its computing complexity into a realizable level. The related-key attack we present in this paper simultaneously uses the information leaked from different chaotic sequences generated by related keys and combines the ideas of linear cryptanalysis and divide-and-conquer attack together, hence greatly enhances the efficiency of divide-and-conquer attack. As an example, we test the related-key attack on the ZLL chaotic cipher with a 64-bit key on a Pentium IV 2.5 GHz PC, which takes only 8 minutes and 45 seconds to recover all bits of the key successfully.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
609. A relevance vector machine with rough set theory model in analyzing the life cycle of new economic firms
- Creator:
- Hsu, Ming-Fu, Ping-Feng, Pai, and Chung, Wei-Shih
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Corporate life cycle, rough set theory, relevance vector machine, and transparency and disclosure
- Language:
- English
- Description:
- The subprime mortgage crisis and subsequent financial tsunami have raised considerable concerns about financial risk management and evaluation. This is nowhere more apparent than in new economic firms (NEFs) with large economic targets and heavy R&D expenses, such as firms in the electronics industries. With its potential for extreme growth and superior profitability, the electronic industries in Taiwan have been in the financial stock market spotlight. Recently, the relevance vector machine (RVM) was reported to have considerably less computation complexity than support vector machines (SVM) models, since it uses fewer kernel functions. Another emerging technique is rough set theory (RST), which derives rules from data. Based on the corporation life cycle theory (CLC), this study developed a relevance vector machine with rough set theory (RVMRS) to predict the status of a corporation in the decline stage. To demonstrate the performance of the designed RVMRS model, the study used electronic industries data from the Taiwan Economic Journal data bank, Taiwan Security Exchange, and Securities and Futures Institute in Taiwan. Experimental results revealed that the presented RVMRS model can predict the decline stage in a firm's life cycle with satisfactory accuracy, and generate rules for investors, managers, bankers and regulators that enable them to make suitable judgments. In addition, this study proved that the transparency and information disclosure index (TDI) is crucial to predicting the financial decline of corporations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
610. A remark on $k$-systems in groups
- Creator:
- Parmenter, M. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- math and $k$-systems
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public