899 research outputs found
Shoreseine (Yendi) operations during the monsoons at Karwar, Uttar Kannada District of Karnataka
After the introduction of trawlers in the 1970s
and purseseiners in 1980s, the rampan shoreseine,
which was a gear of primary importance along the
Uttar Kannada coast, was phased out or replaced
and has gradually disappeared. Legislation was
promulgated on fishing by mechanised boats in
coastal areas in the interest of traditional fishers who
fish within 10 m depth
Osmoregulatory ability of Penaeus monodon (fabricius) In relation to varying salinities
Adult Penaeus rnonodon osmoregulated well between salinities 3 and 45%0 for 24 and 48 hour duration
with isosmotic points around = S18.5% and =S 23.520 respectively. A duration of 48 hr is essential for
prawns to adjust to the new medium. Influence of eyestalk removal on osmolal concentration of haemo-
lymph was studied. There was a significant decline in osmolal concentration in destalked prawns from
4 to 18hr after eyestalk surgery performance, but later recouping effect was seen. In destalked prawns
when eyestalk extract was administered, the level of osmolal concentration did not decrease but always
remained high throughout the experimental period. Probable reasons for such changes are discussed
Nonlinear dynamics in an alternating gradient guide for neutral particles
Neutral particles can be guided and focussed using electric field gradients
that focus in one transverse direction and defocus in the other, alternating
between the two directions. Such a guide is suitable for transporting particles
that are attracted to strong electric fields, which cannot be guided using
static fields. Particles are only transmitted if their initial positions and
transverse speeds lie within the guide's phase space acceptance. Nonlinear
forces are always present in the guide and can severely reduce this acceptance.
We consider the effects of the two most important nonlinear forces, a term in
the force that is cubic in the off-axis displacement, and a nonlinear term
which couples together the two transverse motions. We use approximate
analytical techniques, along with numerical methods, to calculate the influence
of these nonlinear forces on the particle trajectories and on the phase space
acceptance. The cubic term alters the focussing and defocussing powers, leading
either to an increase or a decrease of the acceptance depending on its sign. We
find an approximate analytical result for the phase space acceptance including
this cubic term. Using a perturbation method we show how the coupling term
leads to slow changes in the amplitudes of the transverse oscillations. This
term reduces the acceptance when it reduces the focussing power, but has little
influence when it increases that power. It is not possible to eliminate both
nonlinear terms, but one can be made small at the expense of the other. We show
how to choose the guide parameters so that the acceptance is optimized.Comment: 31 pages, 12 figure
Fluctuation in calcium levels in the exoskeleton, Muscle and haemolymph of Penaeus indicus, cultivated In a brackishwater pond
The calcium content in the exoskeleton of Penaeus indicus cultivated in a
brackishwaterpond was found between 4 and 15%, which was low compared to
other crustaceans. The haemolymph calcium was observed always at a higher level
than the calcium in the pond water. Calcium content of pond water and haemolymph
showed a direct relationship wiith the salinity. Relatively high levels of
calcium in muscle and low levels in exoskeleton were observed in June, the probable
reasons for this abrupt fall in the values are discussed
Evaluation of sampling gear for demersal resource surveys
The three demersal trawls evaluated were 38 m HSDT-II, indigenously developed
by CIFT for deep sea fishing in Indian EEZ; and two imported designs, viz.,
45.6 m Expo model demersal trawl and 50 m fish trawl operated from vessels of FSI
and IFP, respectively. Vertical opening at trawl mouth was heighest for 50 m fish
trawl (3.2 m), followed by Expo model demersal trawl (2.5 m) and 38 m HSDT-II
(2.2 m), due to differences in overall dimensions and design features. Estimate of
horizontal opening between otter boards was highest for 38 m HSDT-II probably due
to low drag of the gear, followed by 45.6 m and 50 m trawls. Lowest catch per unit
effort obtained by 38 m HSDT-II is presumably due to smaller dimensions of the gear,
larger codend mesh size and difference in ground rig, in addition to chance factors.
However, 38 m HSDT-II scores on several features desirable in demersal sampling
gear such as simplicity in design and construction, ease of operation; lower twine
surface area and drag; and ground rig suitable for wider range of bottom conditions.
Modifications to make it more effective while sampling for crustaceans and small sized
finfish components are described
Slowing and cooling molecules and neutral atoms by time-varying electric field gradients
A method of slowing, accelerating, cooling, and bunching molecules and
neutral atoms using time-varying electric field gradients is demonstrated with
cesium atoms in a fountain. The effects are measured and found to be in
agreement with calculation. Time-varying electric field gradient slowing and
cooling is applicable to atoms that have large dipole polarizabilities,
including atoms that are not amenable to laser slowing and cooling, to Rydberg
atoms, and to molecules, especially polar molecules with large electric dipole
moments. The possible applications of this method include slowing and cooling
thermal beams of atoms and molecules, launching cold atoms from a trap into a
fountain, and measuring atomic dipole polarizabilities.Comment: 13 pages, 10 figures. Scheduled for publication in Nov. 1 Phys. Rev.
Traditional knowledge on zootherapeutic uses by the Saharia tribe of Rajasthan, India
The present zootherapeutic study describes the traditional knowledge related to the use of different animals and animal-derived products as medicines by the Saharia tribe reside in the Shahabad and Kishanganj Panchayat Samiti's of Baran district of Rajasthan, India. A field survey was conducted from April to June 2006 by performing interview through structured questionnaire with 21 selected respondents, who provided information regarding use of animals and their products in folk medicine. A total of 15 animal species were recorded and they are used for different ethnomedical purposes, including cough, asthma, tuberculosis, paralysis, earache, herpes, weakness, muscular pain etc. The zootherapeutic knowledge was mostly based on domestic animals, but some protected species like the peacock (Pavo cristatus,), hard shelled turtle (Kachuga tentoria), sambhar (Cervus unicolor) were also mentioned as medicinal resources. We would suggest that this kind of neglected traditional knowledge should be included into the strategies of conservation and management of faunistic resources. Further studies are required for experimental validation to confirm the presence of bioactive compounds in these traditional remedies and also to emphasize more sustainable use of these resources
Animals and their products utilized as medicines by the inhabitants surrounding the Ranthambhore National Park, India
The present ethnozoological study describes the traditional knowledge related to the use of different animals and animal-derived products as medicines by the inhabitants of villages surrounding the Ranthambhore National Park of India (Bawaria, Mogya, Meena), which is well known for its very rich biodiversity. The field survey was conducted from May to July 2005 by performing interviews through structured questionnaires with 24 informants (16 men and 8 women), who provided information regarding therapeutic uses of animals. A total of 15 animals and animal products were recorded and they are used for different ethnomedical purposes, including tuberculosis, asthma, paralysis, jaundice, earache, constipation, weakness, snake poisoning. The zootherapeutic knowledge was mostly based on domestic animals, but some protected species like the collared dove (Streptopelia sp.), hard shelled turtle (Kachuga tentoria), sambhar (Cervus unicolor) were also mentioned as important medicinal resources. We would suggest that this kind of neglected traditional knowledge should be included into the strategies of conservation and management of faunistic resources in the investigated area
Traditional zootherapeutic studies in India: a review
The present study aims to review the zootherapeutic practices of the different ethnic communities of India. This work is also an attempt to present a list of animals' use for medicinal purposes by different communities of India. Data were gathered from 15 published research papers of various authors on zootherapeutic studies in India from 2000 to 2007. Approximately 109 animals and their 270 uses are reported in traditional medicine in different parts of India. Of these, the highest numbers of animal species (42, 38.5%) with 50 (18.5%) uses have been reported for the treatment of Respiratory system related problems. Rheumatic and other pains are treated with 32 species (29.4%) in 34 (12.9%) uses. Gastric problems are reported to be treated with 22 (20.2%) species in 26 (9.9%) uses. The mammals constitute the highest number of animals used for medicinal purposes. 44 (40%) mammals, 24 (22%) invertebrates, 18 (17%) birds, 12 (11%) reptiles, nine (8%) fishes and two (2%) amphibians have been reported for medicinal purposes. Of the total 109 animal species reported, 76(70%) are included in IUCN red data list and 36 (33%) animal species are listed in CITES appendix I, II, and III. This work will be helpful in biodiversity conservation in India and also give a clue to investigate bio-active compound in these animal raw materials
An investigation into the roles of chlorides and sulphate salts on the performance of low salinity injection in sandstone reservoirs : experimental approach
Numerous studies have been carried out to ascertain the mechanisms of low salinity and smart water flooding technique for improved oil recovery. Focus were often on brine composition and, specifically the cationic content in sandstone reservoirs. Given the importance of the salt composition and concentration, tweaking the active ions which are responsible for the fluids-rock equilibrium will bring into effect numerous mechanisms of displacement which have been extensively debated. This experimental study, however, was carried out to evaluate the extent of the roles of chloride and sulphate-based brines in improved oil recovery. To carry this out, 70,000 ppm sulphates and chloride-based brines were prepared to simulate formation water and 5,000ppm brines of the same species as low salinity displacement fluids. Core flooding process was used to simulate the displacement of oil by using four (4) native sandstones core samples, obtained from Burgan oil field in Kuwait, at operating conditions of 1500 psig and 50oC. The core samples were injected with 70,000 ppm chloride and sulphates and subsequently flooded with the 5,000 ppm counterparts in a forced imbibition process. Separate evaluations of chloride and sulphate-based brines were carried out to investigate the displacement efficiencies of each brine species. The results showed that the in both high and low salinity displacement tests, the SO4 brine presented better recovery of up to 89% of the initial oil saturation (Soi). Several mechanisms of displacement were observed to be responsible for improved recovery during SO4 brine displacement. IFT measurement experiments also confirmed that there was reduction in IFT at test conditions between SO4 brine and oil and visual inspection of the effluent showed a degree emulsification of oil and brines. Changes in pH were observed in the low salinity flooding and negligible changes were noticed in the high salinity floods. These results provide an insight into the roles of chloride and sulphate ions in the design of smart “designer” water and low salinity injection scenarios
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