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2. Capillostrongyloides morae sp. n. (Nematoda: Capillariidae) from deep-sea fish (Teleostei, Moridae) in the western Mediterranean Sea
- Creator:
- González-Solís, David, Carrassón, Maite, and Pérez-del-Olmo, Ana
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Gadiformes, Lepidion lepidion, Mora moro, and Spain
- Language:
- English
- Description:
- A new capillariid nematode, Capillostrongyloides morae sp. n., is described from specimens collected from the stomach and intestine of the common mora, Mora moro (Risso), and the Mediterranean codling, Lepidion lepidion (Risso) (both Gadiformes, Moridae), off the Mediterranean coasts of Spain. The new species shows similar morphological features as other congeneric species occurring in freshwater and marine fishes, but it differs in the length of the body and spicules, the size of the caudal bursa, and the presence of an elevated anterior vulvar lip. Capillostrongyloides morae sp. n. is the second species within the genus for which the presence of a stylet is reported, and the first one in which this structure along with the distribution of cephalic papillae and oral structures (e.g. lips and lobes) are clearly shown by using scanning electron microscopy.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. New bounds for the minimum eigenvalue of the Fan product of two $M$-matrices
- Creator:
- Cheng, Guanghui
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Fan product, minimum eigenvalue, and $M$-matrix
- Language:
- English
- Description:
- In this paper, we mainly use the properties of the minimum eigenvalue of the Fan product of $M$-matrices and Cauchy-Schwarz inequality, and propose some new bounds for the minimum eigenvalue of the Fan product of two $M$-matrices. These results involve the maximum absolute value of off-diagonal entries of each row. Hence, the lower bounds for the minimum eigenvalue are easily calculated in the practical examples. In theory, a comparison is given in this paper. Finally, to illustrate our results, a simple example is also considered.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. On the lonely runner conjecture
- Creator:
- Pandey, Ram Krishna
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- congruences, arithmetic progression, and bi-arithmetic progression
- Language:
- English
- Description:
- Suppose k + 1 runners having nonzero distinct constant speeds run laps on a unit-length circular track. The Lonely Runner Conjecture states that there is a time at which a given runner is at distance at least 1/(k + 1) from all the others. The conjecture has been already settled up to seven (k ≤ 6) runners while it is open for eight or more runners. In this paper the conjecture has been verified for four or more runners having some particular speeds using elementary tools.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Review of the sequential development of Loma salmonae (Microsporidia) based on experimental infections of rainbow trout (Oncorhynchus mykiss) and Chinook salmon (O. tshawytscha)
- Creator:
- Kent, Michael L. and Speare, David J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Microsporidia, Loma salmonae, rainbow trout, Chinook salmon, Oncorhynchus mykiss, and Oncorhynchus tshawytscha
- Language:
- English
- Description:
- Loma salmonae (Putz, Hoffman et Dunbar, 1965) is a common gill parasite of salmonids, and essentially all species in the genus Oncorhynchus are susceptible. Infections occur in both fresh and salt water. Loma salmonae is directly transmissible by ingestion of spores or infected tissue. The parasite infects the wall of blood vessels of various organs, but the gill is the primary site of infection. Initial infection occurs in the intestine, and xenomas are easily detected in the gills by standard histology at 4-6 wk post-exposure. A few presporogonic stages of the parasite are found in the heart endothelium prior to xenoma formation in the gills. Ultrastructure studies of early infections demonstrated that wandering blood cells transport the meronts to the gills, and that merogony occurs in pillar cells and other cells underlying the gill endothelium. Xenomas develop in these cells, resulting in hypertrophied host cells filled with spores. Xenomas ultimately rupture, and are associated with severe inflammation in which free spores are found in macrophages. The parasites are most pathogenic during this phase of the infection, resulting in severe vasculitis and clinical disease. Both rainbow trout (Oncorhynchus mykiss) and Chinook salmon (Oncorhynchus tshawytscha) recover from infections, but free spores persist in kidney and spleen phagocytes for many months after xenomas are absent in Chinook salmon. Fish that have recovered from the infection show strong immunity against the parasite, lasting up to 1 year. Fish are susceptible to infection by other routes of exposure by spores; co-habitation, anal gavage, and intramuscular, intraperitoneal and intravascular injection. Autoinfection probably occurs following release of spores in blood vessels after xenomas rupture. The optimal temperature for L. salmonae infections is 15-17°C, with a permissive range of 11-20°C.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. The prevalence of Borrelia burgdorferi sensu lato in Ixodes persulcatus and I. ricinus ticks in the zone of their sympatry
- Creator:
- Korenberg, Edward I., Kovalevskii, Yurii V., Levin, Michael L., and Shchyogoleva, Tatyana V.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Borrelia, prevalence, Ixodes persulcatus, Ixodes ricinus, and sympatry
- Language:
- English
- Description:
- A total of 7210 unfed adult Ixodes persulcatus Schulze, 1930 and I. ricinus (L., 1758) ticks were collected from the vegetation by flagging in 35 study sites located in the zone of their sympatry (mainly in Leningrad region, Russia). Borrelia infection in ticks was estimated by the dark-field microscopic analysis of gut contents in standard vital preparations at a magnification of ×600. No correlation was revealed between the series of parameters characterising the abundance of each tick species (τ = -0.13) and between the series of these parameters and the prevalence of Borrelia in each vector. It is concluded that in the broad zone of I. persulcatus and I. ricinus sympatry, the presence and proportion of one vector in the ecosystem does not have any significant effect on the extensity of infection and on the epizootic and epidemic significance of the other vector. Each tick species has its independent (of the other species) and relatively original functional role in the focal ecosystem.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public