An Atom Laser is not monochromatic

We study both numerically and analytically the possibility of using an adiabatic passage control method to construct a Mach-Zehnder interferometer (MZI) for Bose-Einstein condensates (BECs) in the time domain, in exact one-to-one correspondence with the traditional optical MZI that involves two beam splitters and two mirrors. The interference fringes one obtains from such a minimum-disturbance set up clearly demonstrates that, fundamentally, an atom laser is not monochromatic due to interatomic interactions. We also consider how the amount of entanglement in the system correlates to the interference fringes.Comment: 4 figures. Submitted for publicatio

Poverty Among Social and Economic Groups In India in the Nineteen Nineties.

This paper examines the levels and changes in poverty indicators of the rural and urban population in India disaggregated by social and economic groups. The analysis is based on the comparable estimates of poverty on the mixed reference period computed from the unit record data for the 50 th (1993-94) and the 55 th (1999-2000) rounds of the Consumer Expenditure Surveys conducted by the National Sample Survey Organisation. The issue is how far different social and economic groups shared the overall decline in poverty in the 1990s. Four poverty indicators are considered, namely, headcount ratio,the depth and severity measures (PGI and FGT*) as also the absolute size of the poor population. The social groups most vulnerable to poverty have been identified to be the scheduled caste households and the scheduled tribe households with both these groups having above average levels of poverty indicators in the rural and the urban population.Among the economic groups, the most vulnerable groups are the agricultural labour households (rural) and the casual labour households (urban) each having the highestlevels of the poverty indicators in their respective population segments. In terms of changes in poverty in the 1990s, it is found that while the scheduled caste and the agricultural labour (rural) and the casual labour (urban) households experienced declines in poverty on par with the total population, the scheduled tribe households fared badly in both the segments. A further disaggregated analysis brings out the consequences for poverty of combined social and economic vulnerabilities. The paper also presents poverty indicators adjusted for between-(economic and social) group disparity and discusses the implications of the empirical results for the design of a strategy for poverty reduction.India, Poverty, Scheduled Castes & Scheduled Tribes, Labour Households

The Poor in the Indian Labour Force in the 1990s

Comparable all-India estimates of the number of workers and unemployed in 'below-poverty-line' households - together defining the poor in the Indian labour force - are presented for 1993-94 and 1999-2000. Also presented is the gender, activity-status and the rural-urban composition of this group for the two time points. From a level of 115 million (43 million females and 21 million urban) the number of working poor declined by a little over 12 million - almost entirely in rural India - over the six-year period. Over 51 (36) percent of the rural (urban) working poor were engaged in unskilled mannual labour with a further 46 percent (44 percent in urban India) being absorbed by low-productivity self-employment.India, Working Poor, Poor in Labour Force.

Emerging light and hand jigging fishery for cephalopods along Ratnagiri coast, Maharashtra

Cephalopods have emerged as one of the prime foreign exchange earners in India. Trawl nets operating up to 100 m depth account for nearly 85% of the cephalopod landings and use of high opening bottom trawl nets resulted in rapid increase in production. Other gears that exploit cephalopods as bycatch are boat seines, purse seines and dol nets. Jigging, a specialised fishing method developed for cephalopods in Japan, has slowly emerged in India too. Cephalopod jigging by hand has been reported along various places such as Vizhinjam, Kanyakumari, Palk Bay coast, Tuticorin, Karnataka, Devipattinam and Keelakarai in the Gulf of Mannar. The present report of squid jigging off Ratnagiri appears to be the first report from the state of Maharashtr

Occurrence of Octopus vulgaris Cuvier, 1797 at Mumbai, Maharashtra

Octopuses popularly called as ‘devilfish’ are caught mainly as bycatch in the bottom trawl. Due to the growing demand for octopus in the international market, octopus fishery is catching up in Maharashtra. The main fish landing centres for octopus in Mumbai are New Ferry Wharf and Sassoon Dock. Octopuses contribute 3.6% towards the total cephalopod catch in Mumbai. Ommen (1971, 1977) identified many new species of octopus along the west coast of India

Octopus landing at Mumbai Fishing harbour, New Ferry Wharf

Octopuses in the continental shelf and oceanic region are caught mainly as by catch in the bottom trawl and the major genera are Octopus, Cistopus and Eledone.The three main species which constitute the fishery of Mumbai are Octopus dollfusi, Cistopus indicus and Octopus membranaceous.They are processed and sold in local market

Record of Loliolus investigatoris (Goodrich, 1886),Loliginid squid, Doryteuthis singhalensis (Ortmann, 1891) and Onychoteuthis baski (Leach, 1817) occurring off Mumbai waters

Expansion of fishing areas reported new records of cephalopods were reported from various places all along the coast.The species is processed and exported wholly as ‘baby squids’ alongwith the catch of juveniles of Loligo duvaceli.Loliolus investigatoris (Goodrich, 1886) (Fig.1) occur infrequently in trawl catches.Onychoteuthis baski was also reported which was earlier reported in Andamans and Nicobar islands on a cruise of FORV Sagar Sampada

Emergence of squid jigging in India

Cephalopods, locally known as 'Makul', have emerged in recent times as one of the prime foreign exchange earners in India. Trawl nets operating up to 100 m depth account for nearly 85% of the cephalopod landings in Indian marine waters. The introduction of high opening bottom trawl nets resulted in rapid increase in cephalopod productio

Commercially exploited edible bivalves off Mumbai

Bivalves are benthic molluscs occurring in intertidal to subtidal areas. In the food chain they feed low, mainly on plankton and detritus, which are abundantly available in the natural waters circulated by the tides . . Many species of bivalves occur abundantly along the Indian coast of which at least 50 species are commercially important. Edible oysters, clams, cockles, mussels and scallops are the prime groups, which contribute towards the fishery in the marine, estuarine and freshwater habitats