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The largest continental shelf Oxygen Minimum Zone (OMZ) in the world is formed along the Indian western shelf in the eastern Arabian Sea during the Southwest Monsoon [(SWM); June–September], which is a natural pollution event associated with the coastal upwelling. This study examines the composition, abundance, and distribution of copepods during the Northeast Monsoon [(NEM); November to February] and SWM in 50 m depth zones along the Indian western shelf in the eastern Arabian Sea. The NEM was characterised by warm, stratified, and low-salinity waters in the southeast Arabian Sea and cold, high-salinity, and well-mixed waters in the northeastern Arabian Sea. During the SWM, cold and Dissolved Oxygen (DO) deficient waters (<22 μM/0.5 ml L−1), which are the signs of coastal upwelling, were evident all along the study zone, but with more intensity off Kochi, Mangalore, and Goa in the south than off Mumbai and Okha in the north. The zooplankton total biomass and abundance showed seasonality with a general decrease during the SWM (av. 3.68 ± 1.29 ml m−3 and av. 5711 ± 3096 Ind. m−3, respectively) compared to the NEM (av. 7.37 ± 2.17 ml m−3 and av. 14,473 ± 4966 Ind. m−3, respectively). At the same time, the abundance of Polychaeta and Siphonophora showed an increase during the SWM (av. 1187 ± 1055 Ind. m−3 and av. 169 ± 119 Ind. m−3, respectively), probably a result of the DO deficient waters associated with upwelling. Two striking seasonal features in Copepoda community were evident in this study: (a) a compositional shift from Cyclopoida dominant during the NEM to Calanoida dominant during the SWM, and (b) the coastal OMZ along the Indian western shelf during the SWM was dominated by Calanoida, which include oceanic OMZ species such as Pleuromamma indica , Lucicutia flavicornis , L.paraclausii , Eucalanus elongatus , Subeucalanus pileatus , S.subcrassus , and Clausocalanus furcatus. This forms a clear imprint for the extension of the oceanic OMZ into nearshore waters during the SWM due to coastal upwelling. • Considered Copepoda as an indicator of coastal hypoxia along the Indian western shelf. • A compositional shift of Copepoda was evident during different seasons. • Many Copepoda of oceanic OMZ were found in the coastal hypoxic zones. • The study shows the biological continuity of the coastal and oceanic OMZ. [ABSTRACT FROM AUTHOR]

• Presents the copepods in the OMZs of the Arabian Sea (AS) and the Bay of Bengal (BoB). • Summarises the oceanography of a thicker OMZ in the AS than in the BoB. • Lucicutia grandis is an indicator of the lower boundary of OMZ in the AS. • Calanoides carinatus is a diapausing species of OMZ in the AS. • A severe lack of information exists on OMZ copepods in the BoB. The Arabian Sea and the Bay of Bengal are cul-de-sacs of the northern Indian Ocean, and they contain more than half of the world's Oxygen Minimum Zones (OMZs). The current study reviews the vast and advancing literature on the oceanographic settings that lead to distinct OMZs in the Arabian Sea and the Bay of Bengal and links them with the copepods thriving there, their status, and likely adaptations. The Arabian Sea has a thicker perennial subsurface OMZ (∼1000 m) than the Bay of Bengal (∼500 m), which is linked to high plankton production via upwelling and winter convection in the former and river influx and mesoscale eddies in the latter. Studies world over show that OMZs adversely affect the zooplankton community as their core always sustains reduced zooplankton biomass. Exclusive studies on copepods in the perennial OMZ in the northern Indian Ocean have been limited to the Arabian Sea so far, which showed that the calanoid copepod Lucicutia grandis is an indicator species of the OMZ lower boundary, whereas Calanoides natalis is a diapausing species in the OMZ. Studies also evidenced that many calanoids (Pleuromamma indica , Lucicutia longicornis , Rhincalanus nasutus , Paracalanus aculeatus , Eucalanus attenuatus , Euchaeta rimana , Subeucalanus subcrassus), cyclopoids (Oithona nana , Oncaea conifera , Oncaea subtilis , Saphirina), Harpacticoids (Microsetella sp., Aegisthus mucronatus) and Mormonilloids (Mormonilla minor) living in the perennial OMZ are either vertical migrators or having a patchy distribution between the epipelagic to the deeper OMZ stratum. These OMZ copepods are believed to have distinctive growth and reproductive traits that allow them to exist in the OMZs. Their high enzyme activity allows them to carry out vertical migration, their high lipid reserves allow them to stay alive in starving conditions, and their slow lifestyle reduces their energy consumption in deeper OMZs. Unlike the perennial OMZs in the Arabian Sea, copepods in the seasonal OMZs in the coastal upwelling zones are almost unexplored, except for a recent attempt that demonstrated that cyclopoids have better survival strategies there. The Arabian Sea and the Bay of Bengal around India have a strong seasonal exchange of their water masses, but how they influence and shape the copepod communities in these regions and the OMZs they harbour is completely unknown. [ABSTRACT FROM AUTHOR]

This baseline study on microplastics (MPs) in calanoid copepods in the Kochi backwaters (KBW), India's largest estuary system on the west coast, focuses on (a) the spatiotemporal variations of MPs with the seasonal hydrography setting, and (b) how man-made flow restrictions of a large saltwater barrage contribute to MPs in copepods and their potential to transfer to higher trophic levels. This study found that MPs in copepods in the KBW ranged from av. 0.01 ± 0.014 to 0.11 ± 0.03 no./ind. seasonally. When the saltwater barrage shutters were fully/partially closed during the Pre-monsoon/Northeast Monsoon, MPs in copepods were considerably larger (av. 0.11 ± 0.03 no./ind., and av. 0.075 ± 0.02 no./ind., respectively) as compared to the Southwest Monsoon (av. 0.03 ± 0.01 no./ind.), when the barrage shutters were fully open. This shows the potential of man-made flow restrictions to increase the bioconcentration of MPs in copepods and their possible transfer to higher trophic levels through the food chain, adding to the region's previous discovery that much higher trophic level resources are polluted with a high concentration of MPs. • Seasonal distribution of MPs in copepods in the KBW is presented. • Thanneermukkom barrage (TB) favours the accumulation of MPs in copepods. • Copepods accumulated more MPs during non-monsoon seasons. • MPs accumulated in copepods have the potential to transfer to higher trophic levels. • Periodic open and close of TB is suggested. [ABSTRACT FROM AUTHOR]

Abstract: In data mining, frequent itemsets plays an important role which is used to identify the correlations among the fields of database.In this paper, we propose a new association rule mining algorithm called Double Hashing Based Frequent Itemsets, (DHBFI) in which hashing technology is used to store the database in vertical data format. This double hashing technique is mainly preferred for avoiding the major issues of hash collision and secondary clustering problem in frequent itemset generation. Hence this proposed hashing technique makes the computation easier, faster and more efficient.Also this algorithm eliminates unnecessary redundant scans in the database and candidate itemset generation which leads to less space and time complexity. [Copyright &y& Elsevier]

The baseline study of Microplastics (MPs) in zooplankton (copepods, chaetognaths, decapods, and fish larvae) from six different zones along India's west coast (off Kanyakumari/Cape Comorin, Kochi, Mangalore, Goa, Mumbai, and Okha) in the Eastern Arabian Sea (EAS) is presented here with their vast ecosystem impacts. This investigation revealed that zooplankton in all six zones accumulated MPs pellets (52.14%), fibres (28.40%), films (10.51%), and fragments (8.95%). The highest average retention of MPs (MPs/individual) was found in fish larvae (av. 0.57 ± 0.18) while copepods had the lowest (av. 0.03 ± 0.01). The presence of low-density polyethylene, polypropylene, polystyrene, and polyethylene terephthalate was confirmed by Raman Spectra of MPs. The MPs in zooplankton found in this study (av. 22 ± 7 pieces/m3) were nearly 2-fold greater than those found in some of the world's most densely populated areas. It is shown that the strong southerly coastal currents could advect the MPs contaminated water mass too far away, having the potential to affect the fish and corals. • This pilot study on Microplastics (MPs) was focused on the west coast of India. • MP contamination in selected marine zooplankton groups is being investigated. • Out of four kinds of MPs found, the pellet type was the dominant one. • MPs increased at higher trophic levels within the zooplankton community. • High MPs in zooplankton and the coastal currents aggravate the risk of transferring them to fishes and corals. [ABSTRACT FROM AUTHOR]

Even though many studies refer to copepods as potential indicators of hydrographical settings and/or water masses, focused studies on this aspect are very scarce in Indian waters. Hence, this study assesses the hydrography and the copepod composition in a cross-shore transect (7–30 m depth zone) off Kochi along the southwest coast of India during different seasons to understand how seasonal hydrography alters the composition of copepods. The copepod community in the study area was found to consist of 36 species (26 dominant) during the Southwest Monsoon [(SWM) June to September], 31 species (16 dominant) during the Northeast Monsoon [(NEM) November to February], and 39 species (26 dominant) during the Pre-Monsoon [(PRM) March to May]. The salient observations in this study are (a) a higher contribution of cyclopoids (45–50%) during the oligotrophic PRM when the microbial food web was dominant; (b) the dominance of several truly estuarine copepods (Acartia plumosa , Acartiella keralensis , Pseudodiaptomous annandalei , and P. serricaudatus) during the SWM when the flushing of the adjacent estuarine system (Kochi backwaters) was the seasonal highest; and (c) the dominant occurrence of Temora turbinata , commonly referred to as an indicator of coastal upwelling, during both the SWM and the NEM indicates their conducive conditions in the study area during both seasons and (d) the occurrence of copepods Acartia danae , A. erythraea , Acrocalanus gibber , A. gracilis , Centropages orsinii , C. tenuiremis , Corycaeus catus , C. speciosus , Oithona similis , O. spinirostris , Oncaea venusta , Paracalanus parvus , and Undinula vulgaris in the study area regardless of seasons. The study concludes that, while the presence of truly estuarine copepods in the study area can be attributed to estuarine watermass indicators, the presence of several other dominant species found regardless of the season cannot, as their occurrence is widespread in the eastern Arabian Sea and the western Bay of Bengal, owing to seasonal water mass exchange between the two regions. • This seasonal study was conducted off Kochi, on the Indian Southwest coast. • How seasonal hydrography alters the composition of copepods was addressed. • Cyclopoids (45–50%) were dominant during the oligotrophic Pre-Monsoon through the microbial loop. • The presence of several truly estuarine copepods in the coastal waters during the Southwest Monsoon. • Rapid estuarine flushing during the Southwest Monsoon causes the presence of such copepods. [ABSTRACT FROM AUTHOR]

The focal adhesion targeting (FAT) domain of focal adhesion kinase (FAK) is critical for recruitment of FAK to focal adhesions and contains tyrosine 926, which, when phosphorylated, binds the SH2 domain of Grb2. Structural studies have shown that the FAT domain is a four-helix bundle that exists as a monomer and a dimer due to domain swapping of helix 1. Here, we report the NMR solution structure of the avian FAT domain, which is similar in overall structure to the X-ray crystal structures of monomeric forms of the FAT domain, except that loop 1 is longer and less structured in solution. Residues in this region undergo temperature-dependent exchange broadening and sample aberrant phi and psi angles, which suggests that this region samples multiple conformations. We have also identified a mutant that dimerizes ∼8 fold more than WT FAT domain and exhibits increased phosphorylation of tyrosine 926 both in vitro and in vivo. [Copyright &y& Elsevier]