543 research outputs found
Magnetic wire-based sensors for the micro-rheology of complex fluids
We propose a simple micro-rheology technique to evaluate the viscoelastic
properties of complex fluids. The method is based on the use of magnetic wires
of a few microns in length submitted to a rotational magnetic field. In this
work, the method is implemented on a surfactant wormlike micellar solution that
behaves as an ideal Maxwell fluid. With increasing frequency, the wires undergo
a transition between a steady and a hindered rotation regime. The study shows
that the average rotational velocity and the amplitudes of the oscillations
obey scaling laws with well-defined exponents. From a comparison between model
predictions and experiments, the rheological parameters of the fluid are
determined.Comment: 14 pages 7 figures, accepted in Physical Review
Targeted trawl fishery for moontail bullseye, Priacanthus hamrur off Mangalore for surumi production
Moontail bullseye, Priacanthus hamrur has been
forming a part of the trawl fishery off Mangalore,
caught from a depth beyond 100 m ever since
deepsea trawling started off the coast. This is not a
preferred edible species in Karnataka and was not a
species considered for targeted fishery
Unusual catch rates of cuttlefish in a multiday trawler
Cuttlefish is one of the commercially important
group of cephalopods caught by multi-night trawlers
along the coast of Karnataka. The catch rate of
cuttlefish in multiday trawlers varies from <5 kg/haul
during December-April period to 50-300 kg/haul
during the peak fishing season in August-
September
Sequential networks for cosmic ray simulations
A hybrid model of generating cosmic ray showers based on neural networks is presented. We show that the neural network learns the solution to the governing cascade equation in one dimension. We then use the neural network to generate the energy spectra at every height slice. Pitfalls of training to generate a single height slice is discussed, and we present a sequential model which can generate the entire shower from an initial table. Errors associated with the model and the potential to generate the full three dimensional distribution of the shower is discussed
Observations on the landing of Odonus niger at Mangalore
The redtoothed triggerfish (Odonus niger) of the
family Balistidae is a reef associated species landed
by trawl nets operated along the Karnataka coast. This
species forms dense aggregations in inshore waters
and were not targeted till recently due to their poor
market demand. The triggerfish shoals are intentionally
avoided by the trawlers and the incidental catches are
either discarded or brought ashore when there is
available deck space for storage. Such small quantities
landed are auctioned along with the miscellaneous
fish groups. Some interest was evinced on this species
by the fish meal traders due to limited availability of
raw materials during the year 2008
Marine microalgal extracts on cultivable crops as a considerable bio-fertilizer: A Review
849-854Around the globe, all countries whether developing or developed depend on agriculture. Nowadays due to advances in science and agricultural technology, the usage of chemical fertilizers, pesticides and genetically modified crops is increasing day by day to meet the demand of the rising population. This looks helpful to meet our demand but this is a great threat for the future generation as the water and food will be more toxic due to accumulation of pesticides and chemical fertilizers which in turn reduces the soil fertility and contaminate the ground water. Due to this condition, the food web is getting totally collapsed. Because of realization of these problems, people are shifting to organic farming. Current researchers are focusing on terrestrial organic sources for agro production but there are immense sources in the wide marine environment. The marine sources will play a substantial role on agricultural development in the future. Microalgae are the best, as they are cheap, renewable source, easily available and are cultural organisms. Moreover, microalgae contain all the essential nutrients needed for plant growth. The majorities of microalgae are capable to fix the atmospheric nitrogen and are effectively used as bio-fertilizers. This review focuses on the broad overview of bio-fertilizers with special reference on marine derived microalgal bio-fertilizers and its role in increasing crop production by altering various physiochemical parameters of diversified agricultural crops
Sex ratio distortion in the Nesolynx thymus (Hymenoptera: Eulophidae), an ecto-pupal parasitoid of uzifly, Exorista sorbillans (Diptera: Tachinidae)
The reproductive alterations induced by maternally inherited alpha-proteo-bacteria Wolbachia to their hosts is a well-documented phenomenon. In Nesolynx thymus, a gregarious hymenopterous ecto-pupal parasitoid of the uzifly, Exorista sorbillans, diagnostic PCR assay using specific primers revealed the presence of Wolbachia. Following genetic crossing experiments, we observed a female biased sex ratio of 1 : 9.5 at 25 degrees C and 1 : 3 male to female ratio when the populations were exposed to heat shock 33 degrees C for six hours. Furthermore, we found infection polymorphism, where female parasitoids are infected by Wolbachia but males are not infected. Infected eggs develop into females, whereas uninfected eggs develop parthenogenetically into males. The results are discussed in the context of the possible mechanism of sex-ratio bias caused by Wolbachia
POM2/CSI1 is essential for functional association of cellulose synthase and microtubules in Arabidopsis
In plants, regulation of cellulose synthesis is fundamental for morphogenesis and plant growth. Cellulose is synthesized at the plasma membrane, and the orientation of synthesis is guided by cortical microtubules; however, the guiding mechanism is currently unknown. We show that the conditional root elongation pom2 mutants are impaired in cell elongation, fertility, and microtubule-related functions. Map-based cloning of the POM-POM2 locus revealed that it is allelic to CELLULOSE SYNTHASE INTERACTING1 (CSI1). Fluorescently tagged POM2/CSI1s associated with both plasma membrane-located cellulose synthases (CESAs) and post-Golgi CESA-containing compartments. Interestingly, while CESA insertions coincided with cortical microtubules in the pom2/csi1 mutants, the microtubule-defined movement of the CESAs was significantly reduced in the mutant. We propose that POM2/CSI1 provides a scaffold between the CESAs and cortical microtubules that guide cellulose synthesis
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