13,707 research outputs found
Growth responses of microalgae, Chlorella salina and Isochrysis galbana exposed to extracts of the macroalga, Hypnea musciformis
The influence of methanol extract and its fractions of the marine macroalga, Hypnea musciformis on aquaculturally important
microalgae viz., Chlorella salina and Isochrysis galbana were investigated. Lower concentrations of the extract of
H. musciformis resulted in marginal growth gain for C. salina and I. galbana. However, the fractionated extract inhibited the
growth of both microalgae tested, suggesting toxicity. Results signify the importance of macroalgal extract in regulating the
growth of aquaculturally important microalga
Nuclear-spin relaxation of Pb in ferroelectric powders
Motivated by a recent proposal by O. P. Sushkov and co-workers to search for
a P,T-violating Schiff moment of the Pb nucleus in a ferroelectric
solid, we have carried out a high-field nuclear magnetic resonance study of the
longitudinal and transverse spin relaxation of the lead nuclei from room
temperature down to 10 K for powder samples of lead titanate (PT), lead
zirconium titanate (PZT), and a PT monocrystal. For all powder samples and
independently of temperature, transverse relaxation times were found to be
ms, while the longitudinal relaxation times exhibited a
temperature dependence, with of over an hour at the lowest temperatures,
decreasing to s at room temperature. At high temperatures, the
observed behavior is consistent with a two-phonon Raman process, while in the
low temperature limit, the relaxation appears to be dominated by a
single-phonon (direct) process involving magnetic impurities. This is the first
study of temperature-dependent nuclear-spin relaxation in PT and PZT
ferroelectrics at such low temperatures. We discuss the implications of the
results for the Schiff-moment search.Comment: 6 pages, 4 figure
Influence of probiotic bacterium Lactobacillus acidophilus on the survival and growth of pearl oyster Pinctada fucata spat
Combination of micro-alga Chaetoceros calcitrans and the probiotic bacterium
Lactobacillus acidophilus evaluated at 1:1 and 1:2 levels revealed that in the
probiotic treated group, Pinctada fucata spat registered significantly high
survival of 79.7 and 89.0 % (P<0.05) respectively compared to that of 65.0 %
survival in control. The probiotic treated groups also showed significant
improvement in growth in terms of length and weight as compared to the control
group. The probiotic treated spat attained a weight gain of 346.0 ± 1.57 mg (1:1
level) and 382.0 ± 11.76 mg (1:2 level) compared to 296.4 ± 9.04 mg in control
group. The length in terms of dorso-ventral measurement (DVM) increased to
18.68 mm (1:1 level) and 19.6 (1:2 level) mm compared to 13.56 mm in control
group
Capture of a live South African cape locust lobster at Vizhinjam
landing centre informed the capture of a new lobster
hitherto unknown to them. Immediately it was
brought to CMFRI Marine Aquarium and kept alive
and was identified to be slipper lobster of Scyllarides
and the species confirmed as Scyllarides elisabethae,
the South African locust lobster
Captive Breeding and Nursery Rearing of the Indian Seahorse, Hippocampus kuda (Teleostei: Syngnathidae)
Breeding of laboratory-reared 21 pairs of broodstock Hippocampus kuda
(Bleeker 1852) and rearing of their young ones indicated that 262.00 ± 59.00 offsprings
were released during each spawning. A newly born seahorse was (mean ± SE) 7.83 ± 0.11
mm in length with a weight of 1.17 ± 0.009 mg. It could attain a mean length of 31.14 ±
0.66 mm with a mean weight of 16.13 ± 0.60 mg in 30 days when fed ad libitum with
Artemia nauplii. The mean survival per brood cycle was enhanced to 65.22 ± 1.87% from
almost less than 1.0% by improving the rearing conditions
Marine Secondary Metabolites (MSM) from Macro Algae Enhance Bacterial Clearance in Hemolymph of Penaeus monodon
Marine secondary metabolites (MSM) from macro algae were incorporated into four experimental feeds for juvenile shrimp (Penaeus monodon) as follows: 1.0% Hypnea musciformis extract (diet 1); 0.1% H. musciformis extract (diet 2); 1.0% H. musciformis extract with 500 mg Ulva fasciata extract and 50 mg of the antibiotic levamisole (diet 3); 1.0% H. musciformis with 500 mg U. fasciata per kg body weight (diet 4). Diet 3 enhanced bacterial clearance to 99.69% in the hemolymph of shrimp challenged with Vibrio alginolyticus and Vibrio fischeri,significantlyhigherthanclearanceratesinall other treatments and the unmedicated control. Results suggest that feed containing MSM is a good alternative to application of antibiotics in controlling bacterial diseases in shrim
New All-Weather Fishery Harbour For Veraval
Veraval forms one of the major fish landing centres of the Saurashtra coast. The all-weather fishery harbour plan was approved and the World Bank sanctioned Rs. 342 milhon for constructing one each at Veraval and Mangrol. In Veraval the execution of the project was initiated in the year 1977-'78 by the Fisheries Terminus Division(FTD) of the Department of Fisheries
Heuristic algorithms for the min-max edge 2-coloring problem
In multi-channel Wireless Mesh Networks (WMN), each node is able to use
multiple non-overlapping frequency channels. Raniwala et al. (MC2R 2004,
INFOCOM 2005) propose and study several such architectures in which a computer
can have multiple network interface cards. These architectures are modeled as a
graph problem named \emph{maximum edge -coloring} and studied in several
papers by Feng et. al (TAMC 2007), Adamaszek and Popa (ISAAC 2010, JDA 2016).
Later on Larjomaa and Popa (IWOCA 2014, JGAA 2015) define and study an
alternative variant, named the \emph{min-max edge -coloring}.
The above mentioned graph problems, namely the maximum edge -coloring and
the min-max edge -coloring are studied mainly from the theoretical
perspective. In this paper, we study the min-max edge 2-coloring problem from a
practical perspective. More precisely, we introduce, implement and test four
heuristic approximation algorithms for the min-max edge -coloring problem.
These algorithms are based on a \emph{Breadth First Search} (BFS)-based
heuristic and on \emph{local search} methods like basic \emph{hill climbing},
\emph{simulated annealing} and \emph{tabu search} techniques, respectively.
Although several algorithms for particular graph classes were proposed by
Larjomaa and Popa (e.g., trees, planar graphs, cliques, bi-cliques,
hypergraphs), we design the first algorithms for general graphs.
We study and compare the running data for all algorithms on Unit Disk Graphs,
as well as some graphs from the DIMACS vertex coloring benchmark dataset.Comment: This is a post-peer-review, pre-copyedit version of an article
published in International Computing and Combinatorics Conference
(COCOON'18). The final authenticated version is available online at:
http://www.doi.org/10.1007/978-3-319-94776-1_5
Does Scientific Progress Consist in Increasing Knowledge or Understanding?
Bird argues that scientific progress consists in increasing knowledge. Dellsén objects that increasing knowledge is neither necessary nor sufficient for scientific progress, and argues that scientific progress rather consists in increasing understanding. Dellsén also contends that unlike Bird’s view, his view can account for the scientific practices of using idealizations and of choosing simple theories over complex ones. I argue that Dellsén’s criticisms against Bird’s view fail, and that increasing understanding cannot account for scientific progress, if acceptance, as opposed to belief, is required for scientific understanding
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