Determination of metabolic rates and quotients in fish

Before any growth can be,achieved by an organism there must be sufficient energy in the food to provide for the metabolic demands of maintenance and any activity associated with food intake. In culture practices it is possible to reduce these energy costs to a minimum and to optimize food conversion. This can be done through an understanding of the environmental and biological factors affecting metabolic rate with a view to reduce the demands on the system and hence increase the production. It is therefore desirable to examine the broad picture of energy exchange within an animal; then proceed to more specific considerations in fish. Since it is the principles and prospects which are of major interest here, no attempt is made to make this a major review of the subject

Assessment of sensor performance

There is an international commitment to develop a comprehensive, coordinated and sustained ocean observation system. However, a foundation for any observing, monitoring or research effort is effective and reliable in situ sensor technologies that accurately measure key environmental parameters. Ultimately, the data used for modelling efforts, management decisions and rapid responses to ocean hazards are only as good as the instruments that collect them. There is also a compelling need to develop and incorporate new or novel technologies to improve all aspects of existing observing systems and meet various emerging challenges. Assessment of Sensor Performance was a cross-cutting issues session at the international OceanSensors08 workshop in Warnemünde, Germany, which also has penetrated some of the papers published as a result of the workshop (Denuault, 2009; Kröger et al., 2009; Zielinski et al., 2009). The discussions were focused on how best to classify and validate the instruments required for effective and reliable ocean observations and research. The following is a summary of the discussions and conclusions drawn from this workshop, which specifically addresses the characterisation of sensor systems, technology readiness levels, verification of sensor performance and quality management of sensor systems

The role of symmetry in driven propulsion at low Reynolds number

We theoretically and experimentally investigate low-Reynolds-number propulsion of geometrically achiral planar objects that possess a dipole moment and that are driven by a rotating magnetic field. Symmetry considerations (involving parity, $\widehat{P}$, and charge conjugation, $\widehat{C}$) establish correspondence between propulsive states depending on orientation of the dipolar moment. Although basic symmetry arguments do not forbid individual symmetric objects to efficiently propel due to spontaneous symmetry breaking, they suggest that the average ensemble velocity vanishes. Some additional arguments show, however, that highly symmetrical ($\widehat{P}$-even) objects exhibit no net propulsion while individual less symmetrical ($\widehat{C}\widehat{P}$-even) propellers do propel. Particular magnetization orientation, rendering the shape $\widehat{C}\widehat{P}$-odd, yields unidirectional motion typically associated with chiral structures, such as helices. If instead of a structure with a permanent dipole we consider a polarizable object, some of the arguments have to be modified. For instance, we demonstrate a truly achiral ($\widehat{P}$- and $\widehat{C}\widehat{P}$-even) planar shape with an induced electric dipole that can propel by electro-rotation. We thereby show that chirality is not essential for propulsion due to rotation-translation coupling at low Reynolds number.Comment: 5 pages, 5 figure

Transportation of live Finfishes and Shellfishes

Livefish trade, especially the live ornamental fish and live seafood trade, is emerging as a major business venture in most of the tropical countries. Production of livefish through aquaculture has also undergone vast changes during the past 20 years. In aquaculture, transport of broodstock from the wild to the hatchery or seed from the hatchery to the growouts forms one of the basic requirements. The demandfor livefiriflsh and shellfish is rapidly increasir^g and in most of the developed countries, more and more livefish traders and restaurants are offering live fishery products to their customers. Air liftiry of live se<^ood has also increased during the last few years. The mcgor constraint to the development of live seafood export is the lack of information on handling the aquatic organisms after they are caught, right through the transport and sale to the customers. Necessary precautions have to be taken while catching, packing and transporting the aquatic organisms. Apart from careful handling, a thorough knowledge of the behaviour and physiology of the animal is necessary to minimise the stress during storage and transportation

Significance of farm-made feeds in the Indian context

The bulk of shrimp production comes from semi-intensive farming in the brackish water systems. The nutritional requirements of shrimpalong with their feeding in these systems is complex and poorly understood primarily due to the difficulties encountered in quantifying the contribution of naturally available food organisms

Status of feed management

Feed management is playing a vital role in aquaculture as half of the operational cost comes from feed. Great care must be taken unless the farmer will incur loss

Some investigations on the activity of phenol oxidase in the isopod Cirolana fluviatilis

Phenol oxidase activity in the isopod Cirolana fluviatilis averaged 0.0015 w.units/mg protein/min in the larger isopod.samples (10-17 mg) and 0.00034 O.D. units/mg protein/min in the smaller samples (6-9 mg). The enzyme showed equal affinity for epinephrine and dopamine and >5O% affinity for DOPA

The Terrible and Destructive Human Tragedy of Subaltern Kashmir in the light of Agha Shahid Ali’s poetry

Ali depicted in general the terrible and destructive human tragedy of subaltern but in particular he put forth the subaltern voice of Kashmir in the landscape of his poetry, and this novelty emerges from the chaos of Kashmir. He had been educated in English and he develops the interest in English language and literature. So English literature has influenced him and his behavior had changed accordingly that he became well aware about postcoloniality. He wants to get rid from these clenches all the countries of the world as well as his motherland Kashmir which he also represented in his poetry. He is extremely worried not only with his previously colonized home ‘the Indian subcontinent, particularly the region of Kashmir' but also with other cultures subject to the repercussion of colonialism and the modern neocolonial order. He writes poetry of ‘compassionate cosmopolitanism,' which, fixed in his multi-cultural tradition, not only foregrounds an ethics of empathy across countrywide and civilizing limitations but also implies an assessment of colonial and neo-colonial power. His cosmopolitanism is especially meaningful if read in the context of postwar American travel poetry and enables review of the association between “home” and “foreign,” between local issues and universal apprehensions

Histopathological changes in gill, kidney and liver of an estuarine mullet, Liza parsia, induced by sublethal exposure to DDT

Liza parsia were exposed to sublethal (0.02 ppm) concentration of DDT for 15 days. The gill responded initially with copious secretion of mucus, oedematous separation of epithelial cells from the basement membrane and fusion of secondary gill lamellae. Hyperplasia of the cells lining primary gill lamellae and lamellar telangiectases (or aneurysms) was frequently seen after day 10 of exposure. Kidney exhibited hypertrophy of the epithelial cells lining proximal convoluted tubules which was followed by shrinkage in glomerular tufts, increase in Bowman's space, appearance of amorphous eosinophilic materials in the lumina of the tubules and focal necrosis on day 10 of the treatment. Hyaline droplets and casts were also encountered in the epithelial cells and lumina of the proximal tubules. Liver revealed an initial dilation of canaliculi and increased secretion of bile. Thereafter, the displacement of nuclei towards periphery of the hepatocytes, disorganization of blood sinusoids, pyknotic changes in nuclei, cytolysis and vacuolation as well as focal necrosis were noticed after day 10 of the intoxication

Chiral molecules split light: Reflection and refraction in a chiral liquid

A light beam changes direction as it enters a liquid at an angle from another medium, such as air. Should the liquid contain molecules that lack mirror symmetry, then it has been predicted by Fresnel that the light beam will not only change direction, but will actually split into two separate beams with a small difference in the respective angles of refraction. Here we report the observation of this phenomenon. We also demonstrate that the angle of reflection does not equal the angle of incidence in a chiral medium. Unlike conventional optical rotation, which depends on the path-length through the sample, the reported reflection and refraction phenomena arise within a few wavelengths at the interface and thereby suggest a new approach to polarimetry that can be used in microfluidic volumes