Determination of the maturity stages of marine fishes

Determination of the maturity stages of marine fishe

Nesting Pattern Preferences of Stingless Bee, Trigona Iridipennis Smith (Hymenoptera: Apidae) in Jnanabharathi Campus, Karnataka, India

The patterning aspects of nests are receiving increased attention in nature, so we have studied it in human-dwelling environments involving repeated spatio-temporal mold of pattern. Different criteria such as nesting sites, orientations, nest characters, longevity and elevation of nests have been selected to check the level of preferences exhibited by an indigenous resident species of stingless bee, Trigona iridipennis Smith at the Jnanabharathi campus in the southern part of Bangalore (Karnataka). Nesting patterns gave a precise measurement of preference level exhibited by testing different paradigms. The deciduous, shrub type of vegetation helped for successful dominance in higher number of nests to thrive well, which in turn helped to look at the varying patterns of nests. Observations on different nests revealed: i. preference for the habitats made of walls, ii. north facing direction for nest opening, iii. different type of nests with oval-shaped opening and medium-sized exposure outside, iv. nests with more accumulation of mud, resin and wax deposits and v. bees preferring middle elevation range of 11-15 feet for nest-building purely depending on the safer strategies such as availability of flora, protection from predators for better and safe survival at the nesting sites

Some Notes On Queenfishes And Their Fishery Along The Indian Coasts

A large variety of fishes popularly called horse mackerels, shads, trevellies, queenfishes, pompanos, runners etc. comprise the family Carangidae. Among them, the subfamily Scomberoidae represented by the genus Scomberoides (- Chorinemus) is popularly knownas queenfishes.They form an important constituent in the marine fish landings of India. This article highlights some of the taxonomic characters for easy field identification and also to review in brief the status of fishery of this group of fishe

Fishery and biology of yellowfin tuna occurring in the coastal fishery in Indian seas

In the recently convened Workshop on "Stock assessment of yellowfin tuna in the Indian Ocean" (FAO/IPTP, 1991) the present status of the fishery, biology and stock structure of yellawfiil tuna taken by different countries bordering the Indian Ocean have been discussed, and recommednations on the development of the fishery for this species made

Observation of Pure Spin Transport in a Diamond Spin Wire

Spin transport electronics - spintronics - focuses on utilizing electron spin as a state variable for quantum and classical information processing and storage. Some insulating materials, such as diamond, offer defect centers whose associated spins are well-isolated from their environment giving them long coherence times; however, spin interactions are important for transport, entanglement, and read-out. Here, we report direct measurement of pure spin transport - free of any charge motion - within a nanoscale quasi 1D 'spin wire', and find a spin diffusion length ~ 700 nm. We exploit the statistical fluctuations of a small number of spins ($\sqrt{N}$ < 100 net spins) which are in thermal equilibrium and have no imposed polarization gradient. The spin transport proceeds by means of magnetic dipole interactions that induce flip-flop transitions, a mechanism that can enable highly efficient, even reversible, pure spin currents. To further study the dynamics within the spin wire, we implement a magnetic resonance protocol that improves spatial resolution and provides nanoscale spectroscopic information which confirms the observed spin transport. This spectroscopic tool opens a potential route for spatially encoding spin information in long-lived nuclear spin states. Our measurements probe intrinsic spin dynamics at the nanometre scale, providing detailed insight needed for practical devices which seek to control spin.Comment: 7 pages, 2 figures, under consideration at Nature Nanotechnolog

Impressions of a recent visit to Lakshadweep from the fisheries and marine biological perspectives

Lakshadweep has been in the limelight owing to the special considerations shown by the Government of India towards its alround developmentand the welfare of the people. Marine fisheries have to play a key role in maintaining and upgrading the standard of the life in the islands. In this context CMFRI had already contributed to the management of marine fisheries resources and steps are now being taken to expand its research activities in particular fields

Extended Universality of the Surface Curvature in Equilibrium Crystal Shapes

We investigate the universal property of curvatures in surface models which display a flat phase and a rough phase whose criticality is described by the Gaussian model. Earlier we derived a relation between the Hessian of the free energy and the Gaussian coupling constant in the six-vertex model. Here we show its validity in a general setting using renormalization group arguments. The general validity of the relation is confirmed numerically in the RSOS model by comparing the Hessian of the free energy and the Gaussian coupling constant in a transfer matrix finite-size-scaling study. The Hessian relation gives clear understanding of the universal curvature jump at roughening transitions and facet edges and also provides an efficient way of locating the phase boundaries.Comment: 19 pages, RevTex, 3 Postscript Figures, To appear in Phys. Rev.