N-[(E)-Quinoxalin-2-ylmethyl­idene]-1H-indazol-5-amine

In the title mol­ecule, C16H11N5, the mean planes of the quinoxaline and indazole fragments form a dihedral angle of 10.62 (5)°. In the crystal, weak inter­molecular N—H⋯N hydrogen bonds link the mol­ecules into zigzag chains extending in the [001] direction. The crystal packing also exhibits π–π inter­actions [centroid–centroid distances of 3.7080 (2) and 3.8220 (5) Å], which form stacks of the mol­ecules parallel to the a axis

(Z)-2-Amino-3-[(E)-benzyl­ideneamino]but-2-enedinitrile

The asymmetric unit of the title compound, C11H8N4, contains two independent mol­ecules. In the crystal structure, inter­molecular N—H⋯N hydrogen bonds link mol­ecules into ribbons extended in the [100] direction

Diurnal variations in the vertical distribution and abundance of zooplankton in the continental shelf waters off Cochin during April 1991

The present study is based on zooplankton samples collected by vertical hauls from 0-30, 30-60 and 60-90 m depths from a 100 m depth station in the continental shelf (09° 44' N, 75° 42*8) off Cochin for two days at three hourly interval. The mean displacement volume of zooplankton biomass at these depth zones were 6.24, 6.70 and 6.07 ml/100 m water while their numerical counts were 14490,13355 and 11290 no/100 m respectively. The overall mean volume (ml) and number per 100 m in the endre water column (0-90 m) were 6.34 and 13045 respectively and were distributed as 5.89 ml and 11715 no/100 m^ in the daytime and 6.79 ml and 14376 no/100 m^ during night hours respectively. The biomass was dominated by copepods (75.6%), decapod larvae (12.2%), chaetognaths (6.5%) and appendicularians (2.4%) in April. In general, copepods, decapod larvae and appendicularians showed increasing trend in number from the bottom (60-90 m) to the surface layer (0-30 m); chaetognaths, medusae, pteropods, heteropods, salps and doliolids were distributed more in the middle zone (30-60 m); while ostracods and planktonic polychaetes were more in the bottom zone (60-90 m). Distribution of amphipods and ostracods indicated significant diurnal vertical migration. The phenomenon of mid- night sinking was noticed in the case of copepods, chaetognaths, appendicularians, medusae, siphonophores, salps and doliolids

Culture of live feed organisms

In any maricuUure practice, availability of seed is one of the prime requisites for sustaining growth, development and to make the activity viable ecologically and economically. As the natural source of seed is often beset with environmental / conservational problems, the dependable source is production through hatchery techniques. Uninterrupted production and supply of live feeds alone can sustain hatchery operations and to feed the emerging larvae or post larvae with different feed requirements at different stages of development / growth. Technologies developed by CMFRl in this line are given in this paper. The method of culturing important live feed organisms such as micro-algae, rotifers, cladocerans and Artemia salina along with their harvesting and preservation are briefly described in this accoun

Fishery for cephalopods using Fish Aggregating Device off Blangad in Kerala

Fish Aggregating Device (FAD) is being deployed off Blangad a small coastal village in Chavakkad, Thrissur district of Kerala, for catching squids and cuttlefishes. The FADs are made up of coconut spadix (locally known as Kolanjil), plastic bottles, nylon ropes, pieces of fishing nets and sacks containing large quantities of sand. This structure is locally known as Norumbu and fishermen from Colachel and Kanyakumari are mainly involved with this activity. The coconut spadix tied with nylon ropes and plastic bottles as float have sacks filled with sand as anchors (Figs. 1 & 2). This structure errected in the sea in identified sites at a distance of 20-44 km from shore and having 30-50 fathom depth, acts as an aggregating device, especially for cephalopods. The fishers record its position on their Global Position System (GPS) unit and after 5 days arrive to operate hooks & lines (Fig.3). Fishing season is from October-May and during the peak season, around 200 fibre boats are operating from Blangad. Most of the boats are fitted with 2 numbers of 9 hp outboard engines. A tractor is used for hauling the boat to the beac

Childhood cancer in the south Asian population of England (1990–1992)

Cancer incidence in 1990–92 among English south Asian (residents with ethnic origins in India, Pakistan or Bangladesh) and non-south Asian children is compared. Standardized incidence ratios show significant overall excesses in south Asians (131), largely due to higher rates in south Asian boys, and specific excesses for leukaemia (141), lymphoid leukaemia (141), lymphoma (172) and hepatic tumours (375). Aetiological investigation is required. © 2001 Cancer Research Campaign http://www.bjcancer.co

CMFRI Marine Fisheries Policy Series No.15; Fishery Management Plan for Palk Bay Blue Swimming Crab

Crabs are widely distributed in Indian seas and form minor fishery at various regions along the east and west coasts. Crabs contribute a share of 11.1 % in total crustacean landings, with an approximate production of 53476 tonnes in 2017. Three portunid crabs, Portunus pelagicus, Portunus sanguinolentus and Charybdis feriatus form the majority of the regular crab landings in India. The demand for Portunus pelagicus, commonly known as Blue Swimming Crab (BSC) is consistently increasing ever since its export started in the beginning of the century. The State of Tamil Nadu is leading in marine crab landings particularly for the blue swimming crab production in India. The major landing centres for BSC are located in the Palk Bay (PB) and Gulf of Mannar (GoM) areas of Ramanathapuram, Pudukkottai and Thanjavur districts of the state. BSC products form the most important internationally traded commodity from the region and contribute significantly to the livelihood of crab merchants and crab fishers of the area. The Central Marine Fisheries Research Institute has been monitoring the BSC fishery and studying the biology the species along with other marine resources. During the last decade of the 20th century more focused and in-depth studies have been conducted on Portunus pelagicus and established the fact that apart from its fisheries importance, BSC is also a suitable candidate species for farming. This document gives insights on BSC fishing zones, major fishing craft and gears, area wise and centre wise production details, trade, processing industry and export markets. Furthermore, it elucidates the complete life cycle of the species including its growth and reproductive biology as these form essential and integral inputs while formulating the management decisions. As BSC is a highly valuable commodity it necessitates urgent attention to its responsible exploitation and action plan for the judicious management of the resource to accomplish BSC as a sustained fishery. Conclusions have drawn based on the facts and evidences, acquired from exhaustive field and laboratory studies and guidance on a Fishery Management Plan for Palk Bay BSC fishery are presented

Bayesian State-space Implementation of Schaefer Production Model for Assessment of Stock Status for Multi-gear Fishery

Knowing the status of marine fish stock is of utmost importance to develop management strategies for sustainable harvest of marine fishery resources. A widely accepted approach towards this is to derive sustainable harvest levels using time series data on fish catch and fishing effort based on fish stock assessment models like Schaefer’s model that describe the biomass dynamics. In India, the marine fishery is of complex multi-species nature where in different species are caught by a number of fishing gears and each gear harvests a number of species making it difficult to obtain the fishing effort corresponding to each fish species. Since the capacity of the gears varies, the effort made to catch a resource cannot be considered as the sum of efforts expended by different fishing gears. Hence, it demands the importance of effort standardisation for making use in stock assessment models. This paper describes a methodology for the standardization of fishing efforts and assessing fish stock status using Bayesian state-space implementation of the Schaefer production model (BSM). A Monte Carlo based method namely Catch-Maximum Sustainable Yield (CMSY), has also been used for estimating fisheries reference points from landings and a proxy for biomass using resilience of the species. The procedure has been illustrated with data on Indian mackerel (Rastrelliger Kanagurta) collected from the coastal state of Andhra Pradesh, India during 1997-2018. Maximum Sustainable Yield (MSY) of Indian mackerel for Andhra Pradesh has been estimated. A comparison between both CMSY and BSM methods have been made and found that the estimates are in close agreements

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