Superconductivity Near a Quantum Critical Point in Ba(Fe,Co)2As2

We will examine the possible link between spin fluctuations and the superconducting mechanism in the iron-based high temperature superconductor Ba(Fe,Co)2As2 based on NMR and high pressure transport measurements.Comment: Invited paper to m2s-IX (2009

Influence of Sea Surface Temperature on the Gonadal development of Sea urchin Temnopleurus toreumaticus from the Gulf of Mannar, South East Coast of India

This study was conducted for a 20 months period from October 2013 to May 2015 in Gulf of Mannar, south east coast of India. During the investigation the abiotic factors viz., Sea surface temperature (SST), Daylight photoperiod and atmospheric temperature data were collected from International comprehensive Ocean Atmospheric Database (ICOADS) and the reproductive cycle of the sea urchin was studied from the monthly sampling of sea urchin collected from Vedalai landing centre in Gulf of Mannar. The gonads were studied to calculate Gonad index as well histological to categories them into four different stages of the development and this data was compared with abiotic factors to study the influence of it on the reproductive behaviour of sea urchin. The data were analyzed statistically through Pearson correlation and it was found negative between mean monthly gonad index and day length photoperiod, as well as with SST. This clearly indicates that the gonadal development in sea urchin is very much influenced by these two abiotic factors; however other nutritional factors might play greater role in the development gonad

Evaluation of periphyton quantity on different natural substrates in Earthen lined pond

Experiments were conducted in outdoor earthen lined pond to study periphyton quantity on three types of natural substrates such as split bamboo pole, coconut coir and coconut shell, which was placed inside the earthen lined pond filled with seawater for duration of 45 days. Observations were made in every 15th day for growth of periphyton both qualitatively and quantitatively on the three natural substrates and physico-chemical properties of selected pond water such as transparency, water temperature, salinity, pH, Dissolved oxygen, Ammonia (NH3-N), Nitrite (NO2-N), Nitrate (NO3-N), BOD and Chlorophyll ‘a’ were recorded during periphyton samplings. The periphy-ton quantity (34562 ± 671 cells / cm2) observed for coconut coir was higher than the split bamboo pole (33104 ± 810 cells / cm2), and coconut shell (21194 ± 872 cells / cm2) in the final day of the experiment. One way ANOVA of the data collected clearly affirmed that significant differences were observed (P < 0.05) in periphyton quantity among the three substrates tested. A total 16 phyto-periphytic microalgae (Bacillariophyceae – 10 types, Dinophyceae – 4 types and Cyanophyceae – 2 types) and 10 Zoo-periphyton (Copepod- 4 types, Meroplankton – 4 types and Tintin-nidae – 2 types) were recorded from these three substrates. Among the different phyto-periphytic microalgae, Bacil-lariophyceae group were found to be more (Split bamboo pole – 72%, Coconut coir – 73% and Coconut shell – 71%) on three substrates studied. Further, coconut coir was found to be best substrate than split bamboo pole and coconut shell, which can be utilized by fin and shellfishes as natural food

भारत में शूलचर्मी पालन में संभावनाएं

Prospects of Echiniculture in Indi

Echinoid landings at Mandapam, south-east coast of India with a note on gonadal maturity of two species of sea urchins

The sea urchins, belonging to phylum Echinodermata, are a good source of “roe”, (gonads) and are being consumed by humans since pre-historic times. In many countries of the world, it is a delicacy among the food items and in retail markets in Japan, it is sold at prices as high as US$ 600 kg-1. Among the 800 species of echinoids, 105 species are found along the east coast of India and 30 species are recorded along the coast of Tamil Nadu. There is a paucity of information on the biology and ecology of sea urchins and lack of studies on its edibility and palatability. The sea urchin aquaculture called as echiniculture is picking up in subtropics and temperate areas. Importantly, the tropical marine ecosystem of India, which supports diverse flora and fauna is a suitable environment for echiniculture, and the future research needs to be focused to find out the potential species and developing techniques for their aquaculture. The present investigation analysed the landings of echinoderms in the Gulf of Mannar and Palk Bay along the south-east coast of India and also studied the gonadal maturity of two species of sea urchins viz., Salmacis virgulata and Temnopleurus toreumaticus in order to assess their suitability for echiniculture. S. virgulata and T. toreumaticus formed 70 and 30% respectively of the sea urchins landings at Vedalai and Pampan landing centres. The overall sex ratio of both the species did not deviate significantly from 1:1. In S. virgulata the mean monthly gonad index was highest (9.62±0.46) during September 2014 and for T. toreumaticus, the peak GSI was observed during December 2013. Further studies on captive maturation and breeding are needed to explore the potential of these species for echiniculture

Studies on the Influence of Abiotic Factors in the Gonadal Index of Sea urchin Salmacis virgulata from the Gulf of Mannar, South East Coast of India

The present study was conducted to find out whether the abiotic factors in Gulf of Mannar viz., Sea Surface Temperature (SST) and Day light photoperiod would have an effect on the Gonado somatic index of the dominant sea urchin species Salmacis virgulata. A sampling survey for 20 months was conducted from October-2013 to May-2015 in Vedalai landing centre, along the Gulf of Mannar. The freshly collected sea urchin were brought to Mandapam CMFRI and their Gonado Somatic Index (GSI) was estimated. The remote sensing data of the SST from Gulf of Mannar sourced from ICOADS and the daylight photoperiod were compared with the GSI data for 20 months in order to assess the synchrony among the three parameters. The pearson correlation coefficient of the association among the GSI, SST and Photoperiod revealed that there was no significant correlation (p>0.001). The result of the present study revealed that the Gonado Somatic Index of S. virgulata is independent of abiotic factors, which is in contrast to the temperate sea urchin species, where SST and Photoperiod play a major role in gonadal development

19-F NMR Investigation of Iron-pnictide Superconductor LaFeAsO(0.89)F(0.11)

We report 19-F NMR investigation of the new high temperature superconductor LaFeAsO(0.89)F(0.11) (Tc ~ 28K). We demonstrate that low frequency spin fluctuations exhibit pseudo gap behavior above Tc. We also deduce the London penetration depth lambda from NMR line broadening below Tc.Comment: Accepted for publication in Phys. Rev. B (Rapid) with the original submission dat