1,058 research outputs found
Nutritional requirements of Asian seabass, Lates calcarifer
Asian seabass (Lates calcarifer) has emerged as an
important candidate finfish species for aquaculture in
many parts of the world. Availability of seed and
appropriate feed are the two important prerequisites for
development and propagation of aquaculture of any fish
species. After considerable efforts and extensive research,
the Central Institute of Brackishwater Aquaculture (CIBA)
has succeeded in developing captive brood stock and seed
production technology for Asian seabass. Research efforts
on nutritional requirements and development of suitable
formulated feeds have been in progress simultaneously
at CIBA. The nutritional requirements of fish vary with
different growth stages and depend upon the feeding
habits that change according to the morphology of
digesting system. Considerable effort has been made in
Australia, Thailand, Philippines and more recently Israel,
in defining the nutritional requirements of this species in
order to improve production. Understanding the
nutritional requirements of the candidate species is the
first and essential pre requisite for development of cost
effective, efficient and eco friendly feeds
Feeds and feeding of seabass in hatchery, nursery and grow out system using formulated feeds
The requirement of nutrients varies throughout the life
cycle of an individual. At early stages, the requirement of
nutrients is comparatively high which declines with age.
Also the requirements depend upon the feeding habits
that change accordingly to the morphology of digestive
system. Considerable effort has been made in Australia,
Thailand, Philippines and more recently Israel, in defining
the nutritional requirements of seabass in order to improve
production (Boonyaratpalin and Williams, 2001). Feeds
and feeding are the critical factors that determine the
economic viability of commercial aquaculture of the
species concerned and this topic assumes much more
significance in a carnivore species like seabass. Based on
the nutritional requirements we know that this fish
requires a high protein high energy diet. Further, being a
predatory carnivore in nature, weaning them to formulated
feed is the critical factor which influences the success of
grow out culture of seabass. Understanding the nutritional
requirements of the candidate species is the first and
essential pre- requisite for the development of cost
effective, efficient and eco friendly feeds
Is strontium isotope record a strict proxy for chemical weathering rates during the late Miocene (Ocean Drilling Program Site 758A)?
The strontium isotope ratios are examined in the shells of planktic foraminifer Orbulina universa in 20 samples from the late Miocene (8.03-6.36 Ma) sequence of Ocean Drilling Program (ODP) Site 758A, northeastern Indian Ocean. The Sr isotope ratios increased between 7.91 and 7.36 Ma and in the latest Miocene (6.48-6.36 Ma) reflecting high riverine flux from increased chemical weathering and high precipitation in the Himalayan region. The 87Sr/86Sr values decreased during 7.36 to 6.48 Ma coincident with the main phase of Chron-6 negative carbon shift. The carbon shift reflects high delivery of nutrients to the oceans. This contradicts the use of Sr isotope record as a strict proxy for global chemical weathering rates. The Sr isotope ratio should be used with great care in understanding the climatic- tectonic connections
The 2015 April 25 Gorkha (Nepal) earthquake and its aftershocks: implications for lateral heterogeneity on the Main Himalayan Thrust
The 2015 Gorkha earthquake (M-w 7.8) occurred by thrust faulting on a similar to 150 km long and similar to 70 km wide, locked downdip segment of the Main Himalayan Thrust (MHT), causing the Himalaya to slip SSW over the Indian Plate, and was followed by major-to-moderate aftershocks. Back projection of teleseismic P-wave and inversion of teleseismic body waves provide constraints on the geometry and kinematics of the main-shock rupture and source mechanism of aftershocks. The main-shock initiated similar to 80 km west of Katmandu, close to the locking line on the MHT and propagated eastwards along similar to 117 degrees. azimuth for a duration of similar to 70 s, with varying rupture velocity on a heterogeneous fault surface. The main-shock has been modelled using four subevents, propagating from west-to-east. The first subevent (0-20 s) ruptured at a velocity of similar to 3.5 km s(-1) on a similar to 6 degrees N dipping flat segment of the MHT with thrust motion. The second subevent (20-35 s) ruptured a similar to 18 degrees. Wdipping lateral ramp on the MHT in oblique thrust motion. The rupture velocity dropped from 3.5 km s(-1) to 2.5 km s(-1), as a result of updip propagation of the rupture. The third subevent (35-50 s) ruptured a similar to 7 degrees. N dipping, eastward flat segment of the MHT with thrust motion and resulted in the largest amplitude arrivals at teleseismic distances. The fourth subevent (50-70 s) occurred by left-lateral strike-slip motion on a steeply dipping transverse fault, at high angle to the MHT and arrested the eastward propagation of the main-shock rupture. Eastward stress build-up following the main-shock resulted in the largest aftershock (M-w 7.3), which occurred on the MHT, immediately east of the main-shock rupture. Source mechanisms of moderate aftershocks reveal stress adjustment at the edges of the main-shock fault, flexural faulting on top of the downgoing Indian Plate and extensional faulting in the hanging wall of the MHT.Peer reviewe
The 2015 April 25 Gorkha (Nepal) earthquake and its aftershocks: implications for lateral heterogeneity on the Main Himalayan Thrust
The Mw 7.8 Gorkha (Nepal) earthquake on 2015 April 25 initiated ∼80 km northwest of the capital city of Katmandu and ruptured ∼150 km of the frictionally locked downdip segment of the Main Himalayan Thrust (MHT) beneath the central Nepal Himalaya (Avouac et al. 2015). The earthquake resulted in ∼4 m of average slip of the Himalayan Mountains over the Indian Plate in the SSW direction (Mitra et al. 2015). The main-shock fault spanned between the meisoseismal zone of the 1505 (Mw > 8.5) earthquake to its west (Kumar et al. 2006) and the rupture zone of the 1934 (Mw 8.2–8.4) Nepal earthquake to its east (Bilham & Wallace 2005; Sapkota et al. 2013). The last known great earthquake in this region of Nepal occurred in 1833 (M ∼7.5) (Ambraseys & Douglas 2004) and has a significant overlap with the rupture area of the Gorkha main-shock (Adhikari et al. 2015). The main-shock was followed by a series of moderate-to-strong aftershocks, the largest one (Mw 7.3) occurred 18 d after the main-shock, on 2015 May 12 (Fig. 1). Albeit the loss of life and property inflicted by this damaging earthquake and its aftershocks, it has provided an unprecedented opportunity to study the source properties of Himalayan mega-thrust earthquake and its relationship to the geometry of the MHT, which, so far, is poorly understood
Adaptive RRI Selection Algorithms for Improved Cooperative Awareness in Decentralized NR-V2X
Decentralized vehicle-to-everything (V2X) networks (i.e., C-V2X Mode-4 and
NR-V2X Mode-2) utilize sensing-based semi-persistent scheduling (SPS) where
vehicles sense and reserve suitable radio resources for Basic Safety Message
(BSM) transmissions at prespecified periodic intervals termed as Resource
Reservation Interval (RRI). Vehicles rely on these received periodic BSMs to
localize nearby (transmitting) vehicles and infrastructure, referred to as
cooperative awareness. Cooperative awareness enables line of sight and non-line
of sight localization, extending a vehicle's sensing and perception range. In
this work, we first show that under high vehicle density scenarios, existing
SPS (with prespecified RRIs) suffer from poor cooperative awareness, quantified
as tracking error. Decentralized vehicle-to-everything (V2X) networks (i.e.,
C-V2X Mode-4 and NR-V2X Mode-2) utilize sensing-based semi-persistent
scheduling (SPS) where vehicles sense and reserve suitable radio resources for
Basic Safety Message (BSM) transmissions at prespecified periodic intervals
termed as Resource Reservation Interval (RRI). Vehicles rely on these received
periodic BSMs to localize nearby (transmitting) vehicles and infrastructure,
referred to as cooperative awareness. Cooperative awareness enables line of
sight and non-line of sight localization, extending a vehicle's sensing and
perception range. In this work, we first show that under high vehicle density
scenarios, existing SPS (with prespecified RRIs) suffer from poor cooperative
awareness, quantified as tracking error
Euclid preparation: XXI. Intermediate-redshift contaminants in the search for z>6 galaxies within the Euclid Deep Survey
The author list was incorrect in the published version. The name of the collaboration has been added here
Underground Corrosion by Microorganisms Part-I : Analytical Studies of Some Inclian Soils
Fourteen types of Indian soils were analysed far their mechanical, physical, chemical, electrical properties and potential corrosion causing microorganisms. An effort to correlate these individual soil properties was also made
Performance Limitations of Flat Histogram Methods and Optimality of Wang-Landau Sampling
We determine the optimal scaling of local-update flat-histogram methods with
system size by using a perfect flat-histogram scheme based on the exact density
of states of 2D Ising models.The typical tunneling time needed to sample the
entire bandwidth does not scale with the number of spins N as the minimal N^2
of an unbiased random walk in energy space. While the scaling is power law for
the ferromagnetic and fully frustrated Ising model, for the +/- J
nearest-neighbor spin glass the distribution of tunneling times is governed by
a fat-tailed Frechet extremal value distribution that obeys exponential
scaling. We find that the Wang-Landau algorithm shows the same scaling as the
perfect scheme and is thus optimal.Comment: 5 pages, 6 figure
Effect of dietary supplementation of cassia auriculata leaf powder on growth and immune responses of milkfish, Chanos chanos
A 30 days feeding trial was conducted to evaluate the effects of Cassia auriculata leaf powder on growth and
immunomological parameters of the juveniles of Milkfish, Chanos chanos and disease resistance against Vibrio
anguillarum. The juvenile fishes with an average weight of 20±3 g were stocked in four treatments each with
three replicates. Four practical diets were prepared with graded level of Cassia auriculata leaf powder (CAL) at the
rate of 0%, 0.5%, 1% and 1.5% and fed to four treatments respectively named as CAL0, CAL0.5, CAL1 and
CAL1.5. At the end of the experiment blood samples were collected for immunological parameters. After
sampling, the remaining fishes were challenged with 0.1 mL of virulent V. anguillarum suspension at a concentration
of 107
CFU mL-1 and mortality was observed for 7 days. Post challenge sampling was performed for the collection
of blood samples. The growth parameters such as Weight gain%, SGR%, PER were positively affected by Cassia
auriculata leaf powder incorporated diet. Higher weight gain %, SGR% and PER were noticed in CAL1.5 group
followed by CAL1, CAL0.5 and CAL0. The respiratory burst, lysozyme and phagocytic activities were increased
with increasing level of CAL in the diet which indicates better immune response of the fishes fed with CAL. The
higher respiratory burst (0.522 ± 0.03), lysozyme (70.07 ± 1.57) and phagocytic (52.91 ± 1.76) activitieswere
observed in CAL1.5, CAL1 and CAL1.5 groups respectively during pre-challenge and post challenge. There was
significant difference in the survival rate of control (CAL0) and CAL incorporated diet fed groups (P<0.05).
Maximum survival was witnessed in CAL1 followed by CAL1.5 and least survival was in CAL0 group. The results
indicate that diets supplemented with 1% CAL potentially enhance the immune system and effectively protects the
host against V. anguillarum infection and thereby improve the survivability of the fish against this dreadful
pathogen
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