In this study, we examine the kinematics and hydrodynamics of the soft dorsal fin in a representative basal teleost, the rainbow trout (Oncorhynchus mykiss), during steady rectilinear locomotion at 0.5-2.0 body lengths (L) s(-1) and during maneuvering. During steady swimming, dorsal fin height and sweep amplitude decrease with increasing speed. The dorsal fin wake, as viewed within a horizontal...

Neurosteroids are involved in the pathogenesis of hepatic encephalopathy (HE). This study evaluated the effects of finasteride, inhibitor of neurosteroid synthesis, on motor, EEG, and cellular changes in rat brain in thioacetamide-induced HE. Male Wistar rats were divided into the following groups: 1) control; 2) thioacetamide-treated group, TAA (300 mg·kg(-1)·day(-1)); 3) finasteride-treated g...

BACKGROUND Fish fin is a widely used, non-lethal sample material in studies using stable isotopes to assess the ecology of fishes. However, fish fin is composed of two distinct tissues (ray and membrane) which may have different stable isotope values and are not homogeneously distributed within a fin. As such, estimates of the stable isotope values of a fish may vary according to the section of...

Fishes have an enormous diversity of body shapes and fin morphologies. From a hydrodynamic standpoint, the functional significance of this diversity is poorly understood, largely because the three-dimensional flow around swimming fish is almost completely unknown. Fully three-dimensional volumetric flow measurements are not currently feasible, but measurements in multiple transverse planes alon...

The tadpole tail fin is a simple double layer of skin overlying loose connective tissue. Collagen fibres in the fin are oriented at approximately +/-45 degrees from the long axis of the tail. Three tests were conducted on samples of the dorsal tail fin from 6-10 Rana catesbeiana tadpoles to establish the fin's viscoelastic properties under (1) large-deformation cyclic loading at 1 and 3 Hz, (2)...

The Performance of electric vehicle IGPT Pin fin heat sink can be measured by the temperature field and the fluid pressure and other parameters. In order to improve the cooling effect of Pin fin heat sink, diameter, length and distance of the fin was optimized combination. The relationship between pressure drop of the water inlet, outlet and pin fin parameters was analyzed and calculated. It wa...

While experimental analyses of steady rectilinear locomotion in fishes are common, unsteady movement involving time-dependent variation in heading, speed and acceleration probably accounts for the greatest portion of the locomotor time budget. Turning maneuvers, in particular, are key elements of the unsteady locomotor repertoire of fishes and, by many species, are accomplished by generating as...

the purpos of this paper is to aim the maximum heat transfer rate in a plate-fin heat exchanger with a constant volume and a contant surface area at a prescribed pressure drop. this paper propose a method for design a plat-fin heat exchanger in which a maximum pressure drop occurs at a constant volume and surface are. in this paper as a case study, a preheater of a gas turbine which is a plate-...

How fish modulate their fin stiffness during locomotive manoeuvres remains unknown. We show that changing the fin's curvature modulates its stiffness. Modelling the fin as bendable bony rays held together by a membrane, we deduce that fin curvature is manifested as a misalignment of the principal bending axes between neighbouring rays. An external force causes neighbouring rays to bend and spla...

Detecting and separating specific effects of contaminants in a multi-stress field context remain a major challenge in ecotoxicology. In this context, the aim of this study was to assess the usefulness of a non-invasive transcriptomic method, by means of a complementary DNA (cDNA) microarray comprising 1000 candidate genes, on caudal fin clips. Fin gene transcription patterns of European eels (A...