Harpacticoida taxocen diversity in the silty-sandy littoral zone of Kandalaksha Bay of the White Sea

The fauna composition, ecological groups, and life forms of Harpacticoids of soft littoral grounds from 15 sites off the Karelian coast in Kandalaksha Bay of the White Sea were studied. Six types of harpacticoid taxocens with different sets of dominating species are described. On silty sands with clear signs of desalination, the Stenchelia palustris taxocen is common; medium-grained sands are characterized by the Heterolaophonte minuta, Paraleptastacus kliei — Huntemannia jadensis, and Amphiascoides nanus — Scottopsyllus minor taxocens; while on coarse sands, the Ameira parvula and Ameira scotti — Mesochra lilljeborgi taxocens have developed. The diversity of the taxocens is partly explained by the differences in the grain-size composition and salinity at different sites. In addition, groups of various taxocens dwelling on the same type of the sediments were found in different minor bights of the coastline.     

The wadic project: A comprehensive field evaluation of directional wave instrumentation

The results of a comprehensive field trial of nearly all commercially available directional wave measurement systems at the Edda field in the North Sea during winter 1985-86 are presented. The results summarize the accuracy of the principal engineering wave parameters from each system and the dependence on sea state. Limiting factors on system performance and operational problems are also included in the assessment. Overall experience has been good with systems utilizing widely different measurement principles returning consistent results.     

The effect of copper pollution on mitochondrial degeneration

The authors describe the effect of copper pollution on the mitochondria from various areas of the Torpedo marmorata central nervous system. A high percentage of swollen mitochondria has been observed in neurons from animals experimentally exposed to high level of copper (4 ppm). The correlation with age pigment granules is discussed.     

Prediction of wave height based on half-cycle excursion analysis

This paper presents a method to evaluate statistical properties of half-cycle excursions including extreme values. The probability density function for half-cycle excursions for an arbitrarily given wave spectrum is developed based on the Gaussian assumption. The results of numerical computations carried out using wave data obtained during hurricane Camille show that the half-cycle probability density function agrees well with the histogram constructed from the data. The extreme wave height for design consideration computed with risk parameter 0.01 is approximately 20% greater than the observed extreme height.     

Interpretation of a special fine structure in type-IV solar radio bursts

A special fine structure (slowly drifting chains of narrowband fiber bursts), firstly observed during the solar type-IV radio burst on April 24, 1985, is interpreted as the radio signature of whistler waves periodically excited by a switch-on/switch-off process of a loss-cone instability in a localized wave packet of the fast magnetoacoustic mode.     

Variable pulse profile and the accretion geometry in GX 1+4

We suggest that the variable pulse profile of GX 1+4 in the low-energy X-ray region results from the superposition of polar and disk components. The anomalous appearance during the spin-down episode can then be explained, if we consider a transition from thin to thick accretion disk configuration which can develop at midly super-Eddington luminosity levels of the source. a close examination of the data suggests that the intrinsic period of the pulsar is 4 min. A switching disk geometry can provide a natural explanation to pulse profile variations in more luminous accreting binary pulsars and also account for the transition between high and low spectral states seen in the case of the Cyg X-1 and low-mass X-ray binary systems.