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Defining the basic parameters of vibration settings for sealing horizontal surfaces

100%

Ruchinskijj M., Zapryvoda A.

Motrol. Motoryzacja i Energetyka Rolnictwa

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2015

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tom 17

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nr 8

2

Exploitation and repair of hydraulic cylinders used in mobile machinery

86%

Kowalski K., Zloto T.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

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2014

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tom 14

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nr 4

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The diet of the Saimaa ringed seal Phoca hispida saimensis

86%

Kunnasranta M., Hyvarinen H., Sipila T., Koskela J. T.

Acta Theriologica

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1999

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tom 44

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nr 4

The diet of the Saimaa ringed seal Phoca hispida saimensis Nordquist, 1899 was studied by the analysis of stomach contents and by feeding trials with a captive seal. Nine prey species were found in the stomachs, the most important being small schooling fish species: perch Perca fluviatilis, roach Rutilus rutilus, vendace Coregonus albula, smelt Osmerus eperlanus and ruff Acerina cernua, The importance of crustaceans in the diet of the ringed seal in Lake Saimaa is insignificant. Length of the intestinal tract of the Saimaa ringed seal is relatively shorter than those of marine ringed seals. In cafeteria tests on one captive seal the preferred fish species were vendace and smelt. The captive seat displayed clear seasonal variation in feeding activity. The consumption of fish was lowest in springtime and highest in autumn and winter.

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Seasonal numbers of five species of seals in Admiralty Bay [South Shetland Islands, Antarctica]

86%

Salwicka K., Sierakowski K.

Polish Polar Research

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1998

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tom 19

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nr 3-4

5

Human impact upon the environment in the vicinity of Arctowski Station, King George Island, Antarctica

72%

Chwedorzewska K. J., Korczak M.

Polish Polar Research

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2010

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tom 31

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nr 1

45-60

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Histomorphology of prepuberal ovaries in the South American fur seal [Arctocephalus australis Zimmerman, 1783]

72%

Katz H., Perez W., Bielli A., Chavez R.

Folia Morphologica

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2009

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tom 68

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nr 4

277-286

The South American fur seal reproductive histophysiology is scarcely described. This study provides a histological description of prepuberal South American fur seal (Arctocephalus australis) ovaries as well as three-dimensional reconstructions of subcapsular crypts and primordial follicles. Ovaries from fresh dead animals were processed for histology and sliced into serial sections. A portion of the superficial cortex was photographed, and the images were processed using BioVis3d software in order to generate 3-dimensional reconstructions. A. australis prepuberal ovaries conform to the basic structure of pinnipedian species, with a subcapsular crypts system made up of interconnecting cisternae and tubules with multiple openings to the surface. Generally, the primordial follicles were arranged in a monolayer beneath the tunica albuginea and were closely associated with subcapsular crypts. The large number of interstitial cells distributed throughout the cortex was the main histological feature in comparison with previous reports in other seals. Three-dimensional reconstructions modelled the subcapsular crypts microarchitecture and showed the close spatial relationship between the crypts and the primordial follicles. Despite the fact that the general ovarian histological structure was similar to that of other pinnipeds, the large number of interstitial cells is a distinctive feature that raises the question about the origin and function in A. australis with regard to the steroidogenic activity reported in other seal species. (Folia Morphol 2009; 68, 4: 277–286)

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Dive types and circadian behaviour patterns of Saimaa ringed seals Phoca hispida saimensis during the open-water season

72%

Kunnasranta M., Hyvarinen H., Hakkinen J., Koskela J. T.

Acta Theriologica

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2002

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tom 47

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nr 1

Diving and circadian behaviour patterns of 7 free-ranging Saimaa ringed seals Phoca hispida saimensis Nordquist, 1899 were examined by VHF-radiotelemetry during open-water seasons between May and November in Lake Saimaa, eastern Finland. The mean recorded dive duration ranged from 2.8 to 6.5 min, with a maximum of 21 min. The mean dive depth ranged from 9.8 to 15.7 m, with maximum of 39.6 m. The maximum dive depth of each seal was limited by water depth in the study area. The dive depths were positively correlated with dive duration and body mass of the seal. Five different dive types were defined, as based on their depth-time characteristics, each falling into one of the three functional categories: travelling, feeding, and resting. Long duration diving bouts occurred mostly at night and were presumed to be resting dives. Saimaa ringed seals exhibited a circadian pattern of haul-out behaviour that shifted seasonally. During molting (May-June) the seals hauled-out both day and night, but later in summer haul-out was more frequent at night.

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Dynamics of developmental stability of seals and pollution in the Baltic Sea

72%

Zakharov V. M., Valetsky A. V., Yablokov A. V.

Acta Theriologica. Supplement

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1997

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nr 04

Fluctuating asymmetry of skull characters, as a measure of developmental stability, wás studied in two seal species: grey seal Halichoerus gry pus (Fabricius, 1791), and ringed seal Pusa hispida Schreber, 1775 from the Baltic Sea. Seals were collected in three different periods of water pollution of the Baltic Sea. We revealed the same temporal dynamics of fluctuating asymmetry level for both species: it proved to be low in "pre-pollution period" (years 1877-1936), high for the "high-pollution period" (1964-1975), and was again low for the "low-pollution period" (1986-1990). These data suggest that changes in the condition of the seal populations in the Baltic Sea revealed by changes in developmental stability are correlated with the dynamics of the pollution level.

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Cestodes of Antarctic seals

44%

Wojciechowska A., Zdzitowiecki K.

Acta Parasitologica

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1995

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tom 40

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nr 3

Eight cestode species from the family Diphyllobothriidae Luehe, 1910 were found in three seal species, occurring near the Arctowski Station, the South Shetland Islands, West Antarctic. Diphyllobothrium wilsoni (Shipley, 1907), D. scotti Shipley, 1907, D. lashleyi (Leiper et Atkinson, 1914) and Glandicephalus perfoliatus (Railliet et Henry, 1912) occur in the Weddell seal; D. scoticum (Rennie et Reid, 1912), D. quadratum (Linstow, 1892), D. pseudowilsoni sp. n. and immature specimens of D. scotti in the leopard seal; Baylisia baylisi Markowski, 1952 in the crabeater seal. Diphyllobothrium pseudowilsoni sp. n. is distinguished from D. wilsoni (syn. D. mobile Rennie et Reid, 1912) by having more numerous testes, the absence of distinct armature of the cirrus, the arrangement of the vitelline follicles and from D. scotti in the shape of the scolex, the shorter body and neck, and the arrangement of the vitelline follicles. A key to all diphyllobothriid cestodes occurring in Antarctic seals is given.

Ograniczanie wyników

Defining the basic parameters of vibration settings for sealing horizontal surfaces

Exploitation and repair of hydraulic cylinders used in mobile machinery

The diet of the Saimaa ringed seal Phoca hispida saimensis

Seasonal numbers of five species of seals in Admiralty Bay [South Shetland Islands, Antarctica]

Human impact upon the environment in the vicinity of Arctowski Station, King George Island, Antarctica

Histomorphology of prepuberal ovaries in the South American fur seal [Arctocephalus australis Zimmerman, 1783]

Dive types and circadian behaviour patterns of Saimaa ringed seals Phoca hispida saimensis during the open-water season

Dynamics of developmental stability of seals and pollution in the Baltic Sea

Cestodes of Antarctic seals