563 research outputs found
Re-occurrence of oilfish in the landings of the south-west coast of India
On 29.08.2008, 13 specimens of the oilfish, Ruvettus pretiosus Cocco, 1833 were recorded in the trawl landings along with a heavy catch of around 200 t of Coryphaena sp. at the Cochin fisheries harbour. The biggest specimen was 360 mm in TL with a weight of 260 g. The available literature indicates that a single specimen of R. pretiosus measuring 310 mm in TL and weighing 220 g collected from the continental slope off the Quilon Bank (09004'N lat. 75031'E long.) area during November 1968 is so far the only record from the south-west coast of India, besides the two specimens from Laccadives kept in the repository of the museum of Fisheries department at Kavarathi Island. The flesh of R. pretiosus contains more oil and hence the name oilfish. The only other gempylids recorded from the
Cochin area earlier were Neoepinnula orientalis and Rexea prometheoides
Present status of Halophila beccarii seagrass bed in Kadalundi Community Reserve
The occurrence of Halophila beccarii seagrass bed in the
Kadalundi community reserve area was estimated to be
covering an area of more than 2 hectares with a clayey
substratum. The seagrass was growing predominantly
with seaweed Enteromorpha linza and found exposed
during the low tide period. The density of the seagrass
H. beccarii ranged from almost nil during July 2012 to
420 g wet weight/m2 (260 plants/ m2) during December
2012. During April 2013 the distribution of Halophila
plants was represented only by sparse occurrence of
underground parts comprising rhizomes and roots (80
g/ m2). Shoots could not be seen above the sediment
substratum
Phenomemology of a Realistic Accelerating Universe Using Tracker Fields
We present a realistic scenario of tracking of scalar fields with varying
equation of state. The astrophysical constraints on the evolution of scalar
fields in the physical universe are discussed. The nucleosynthesis and the
galaxy formation constraints have been used to put limits on and
estimate during cosmic evolution. Interpolation techniques have been
applied to estimate at the present epoch. The epoch of
transition from matter to quintessence dominated era and consequent onset of
acceleration in cosmic expansion is calculated and taking the lower limit
as estimated from data, it is shown that the
supernova observations beyond redshift would reveal deceleration in
cosmic expansion.Comment: 10 pages, 4 figures, late
Clam resource in the Astamudi Lake, a tropical estuary in sourthern India: Managment and conservation concerns
Clam resources form the livelihood of more
than five hundred families in and around Ashtamudi
Lake, situated between latitude 8°45' - 9°28'
N and 76°28 - 77" 17' E. The alarming increase in
the exploitation of Paphia malabarica in the recent
years forced the Government of Kerala to
impose ban on the fishing activities during its
breeding season based on the recommendations
of CMFRI in 1993
Instruments of RT-2 Experiment onboard CORONAS-PHOTON and their test and evaluation V: Onboard software, Data Structure, Telemetry and Telecommand
The onboard software and data communication in the RT-2 Experiment onboard
the Coronas-Photon satellite is organized in a hierarchical way to effectively
handle and communicate asynchronous data generated by the X-ray detectors. A
flexible data handling system is organized in the X-ray detector packages
themselves and the processing electronic device, namely RT-2/E, has the
necessary intelligence to communicate with the 3 scientific payloads by issuing
commands and receiving data. It has direct interfacing with the Satellite
systems and issues commands to the detectors and processes the detector data
before sending to the satellite systems. The onboard software is configured
with several novel features like a) device independent communication scheme, b)
loss-less data compression and c) Digital Signal Processor. Functionality of
the onboard software along with the data structure, command structure, complex
processing scheme etc. are discussed in this paper.Comment: 24 pages, 2 figures, Accepted for publication in Experimental
Astronomy (in press
RT-2 Detection of Quasi-Periodic Pulsations in the 2009 July 5 Solar Hard X-ray Flare
We present the results of an analysis of hard X-ray observations of the C2.7
solar flare detected by the RT-2 Experiment onboard the Coronas - Photon
satellite. We detect hard X-ray pulsations at periods of ~12 s and ~15 s. We
find a marginal evidence for a decrease in period with time. We have augmented
these results using the publicly available data from the RHESSI satellite. We
present a spectral analysis and measure the spectral parameters.Comment: 12 pages, 8 figures and 3 tables, accepted for publication in The
Astrophysical Journa
Salt Tolerance Mechanisms in Perennial Fodder Grasses
Salinity stress is one of the most damaging stresses in crop plants. It reduces the productivity of the soil and makes it unsuitable for crop cultivation. Fodder crops are considered the best alternative in such uncultivable land. Using salinity-affected land for pasture development is the best alternative to utilize such lands. However, the extent of salinity tolerance varies among different grass species. In this study, Pearl millet Napier hybrids (PMN hybrid) and guinea grass varieties were studied for salinity tolerance in artificially created saline soils in the ratio of 13:7:1:2 (NaCl: Na2SO4: MgCl: CaSO4, respectively) to understand the salinity tolerance mechanisms existing in perennial fodder grasses. Morphologically, the plant height increased in saline-tolerant PMN hybrid varieties, creating more space in nonphotosynthetic tissues to store accumulated salts away from photosynthetic tissues. Whereas in guinea grass tolerant varieties, tiller number increased under salinity. The fresh weight was highest under salinity in the PMN hybrids. In contrast, dry weight was high in control (no salt) plants, implying more water accumulation in PMN hybrids under salinity to dilute the concentration of salts absorbed by the plant. In Guinea grass, varieties like DGG1 had lower leaf succulence than control and high salt excretion through leaf hairs. Tissue tolerance in PMN hybrids was less compared to guinea grass. Membrane stability was maintained in saline-tolerant varieties. The double bond index increased in tolerant PMN hybrid varieties under salinity compared to control, implying fatty acid remodelling for maintaining the stability of membranes under salinity. Fodder grasses adopt various saline tolerance mechanisms based on their growth habit and morphology
Note on Green turtle found on Thikkody beach
The carcass of a green turtle (Chelonia mydas ) was
found on Thikkody beach which is only 10 kms from the
regular nesting area ‘kolavipalam’ located in Kozhikode,
northern Kerala. Found on 27.2.2020, observations
indicated that the turtle was entangled in a gillnet and
had injury to the head
Evolution of Superconducting Properties of Coexistent Bi-2212 and Bi-2223 phases in BSCCO
391-397The evolution of superconducting properties of BSCCO superconductors, inadvertently hosting the two superconducting phases Bi-2212 and Bi-2223 have been investigated in pristine and Pb doped BSCCO. The superconducting transition temperature TC of Bi-2212 phase monotonically increases with increasing Bi-2223 phase fraction. On the other hand Bi-2223 phase exhibits depression in TC for its lower phase fractions (<24%) but attains its bulk value as Bi-2223 phase fraction is increased to 30%. This behavior has been rationalized by invoking the interplay of proximity effects between the two coexisting phases and establishment of Bi-2223 superconducting percolation path. In addition to aiding the formation of BSCCO with higher Bi-2223 phase fraction, the Pb substitution also leads to an enhancement of critical current density by the creation of pinning centres
Quasi-particle model for lattice QCD: quark-gluon plasma in heavy ion collisions
We propose a quasi-particle model to describe the lattice QCD equation of
state for pure SU(3) gauge theory in its deconfined state, for .
The method involves mapping the interaction part of the equation of state to an
effective fugacity of otherwise non-interacting quasi-gluons. We find that this
mapping is exact. Using the quasi-gluon distribution function, we determine the
energy density and the modified dispersion relation for the single particle
energy, in which the trace anomaly is manifest. As an application, we first
determine the Debye mass, and then the important transport parameters, {\it
viz}, the shear viscosity, and the shear viscosity to entropy density
ratio, . We find that both and
are sensitive to the interactions, and that the interactions significantly
lower both and .Comment: 10 pages, 8 figures, epj class file, version accepted for publication
in Euro. Phys.J
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