Jamming in a lattice model of stochastically interacting agents with a field of view

We study the collective dynamics of a lattice model of stochastically interacting agents with a weighted field of vision. We assume that agents preferentially interact with neighbours, depending on their relative location, through velocity alignments and the additional constraint of exclusion. Unlike in previous models of flocking, here the stochasticity arises intrinsically from the interactions between agents, and its strength is dependent on the local density of agents. We find that this system yields a first-order jamming transition as a consequence of these interactions, even at a very low density. Furthermore, the critical jamming density is found to strongly depend on the nature of the field of view.Comment: 5 pages, 3 figures + 3 pages supplementary materia

Manpower information

A description of the NAL nominal roll database (listing basic information about NAL employees) created using the Ingres relational database software. Using this database it is possible to provide a wide variety of reports about NAL staff, respond to a wide assortment of queries and undertake elementary statistical analysis to tabulate (and pictorially depict) the average age of NAL scientists, the future retirement pattern of NAL employees etc

Realistic Chemotherapeutic policies for Tuberculosis in India

A series of controlled studies carried out at the Tuberculosis Chemotherapy Centre have revealed that ambulatory chemotherapy for tuberculosis based on a well-organized clinic service for a year, is virtually as effective as sanatorium treatment for the same period, not only in the immediate therapeutic response in terms of overall radiographic improvement, cavity closure and sputum conversion (Tuberculosis Chemotherapy Centre, Madras, 1959) but also in the likelihood of relapse in a subsequent 4-year period of follow-up (Dawson et al, 1966). Further, principally owing to the rapid sputum conversion of patients receiving effective chemotherapy there was no increased risk of contracting the disease to close family contacts of the patients treated at home, the main risk to them being before treatment had begun (Andrews et al, 1960; Kamat et al, 1966). These studies also clearly showed that the traditionally held virtues of sanatorium treatment namely, prolonged bed-rest, good diet, good airy accommodation, nursing and isolation were remarkably unimportant provided adequate chemotherapy was administered. There have been 5 other controlled trials based on random allocation . reported in the world medical literature which compared either sanatorium treatment with clinic treatment (Tyrell, 1956 ; Bell, 1960) or rest with ambulation (Kay, 1957 ; Tuberculosis Society of Scotland, 1960; Wier et al, 1957 ; Wynn-Williams and Shaw, 1960) and not one demonstrated any advantage either of sanatorium treatment over clinic treatment or of rest over ambulation. Because of these findings and because of the gross shortage of hospital beds for tuberculosis, ambulatory chemotherapy for the major or the entire period of treatment has become the accepted practice in the tuberculosis control programmes in India as well as in many other developing countries of the world

Management of Fresh water Fisheries

The book under review 'Management of Fresh Water Fisheries' by Jacques Arrignon is a very valuable compendium of knowledge on fresh water fisheries presented in three parts, such as ecological fundamentals, fish breeding and management of aquatic media. The contents of the book are a collection appropriate and authentic record of information which heavily deal with many fundamentals, topics, methodology, breeding and culture practices, management of medium which are relevant, applicable and replicable to many universal situations

Deep Sea and Oceanic Resources

Although the marine living resources are renewable, their unbridled exploitation causes irreparable loss to the habitat and the sustainable production of biota. Ever increasing population and demand for cheap fish protein together with the availability of a 8041 km long coast and more than 1,80,000 km2 shallow coastal area have attracted not only the traditional communities but also small-scale entrepreneurs into fishing. The last fifty years' growth of Indian marine fisheries is commendable, which has transformed a subsistence-oriented traditional fmheries into a market oriented commercial fisheries with the support of technical advancements in harvest and post harvest areas and also gained considerable strength and capabilities in landing, storage and processing infrastructure. The growing demand for prime value species of marine resources in domestic and export market has encouraged the commercial exploitation and production of target species through mechaniaation and motorisation

The deep scattering layer (DSL) of Indian EEZ

The deep scattering layer is a trophic network that carry numerous food chains, some of which end up in species of high economic value, such as oceanic squids, tunas, other scombroids, pelagic sharks etc. These diurnally and vertically moving bioacoustic layers are assemblages of mostly negatively phototropic zooplankton and micronekton. The paper examines their characteristics, sampling methods, ecosystem, bio composition and future lines of research and management priorities and reviews all works done in India on the DSL. The major database for this study is drawn from the results of the initial surveys and samplings of FORV Sagar Sampada in the Indian EEZ since 1985