Determination of 129i in water and air samples near a reprocessing plant by neutron activation analysis

The neutron activation analysis was used to determine ¹²⁹I in water and air samples collected in the neighbourhood of a reprocessing plant. The method involved preconcentration of ¹²⁹I on AgI from water samples, separation of Ag⁺, followed by distillation, loading on Dowex-1, irradiation and post irradiation purification steps. Filter air samples were wet oxidised follwed by distillation and other chemical procedure steps as described for water samples. The concentration of ¹²⁹I in rain water and air samples ranged from 0.155×10^?3 to 0.327×10^?3 Bq L^?1 and 0.054×10^?6 to 0.295×10^?6 Bq m^?3 respectively. The average concentration of ¹²⁹I in seawater samples was 0.157×10^?3 Bq L^?1. The concentration of ¹²⁹I obtained in these samples have been translated to dose rates to an individual and have been found to be insignificant.     

Biological treatment of pharmaceutical wastewater

A study of physicochemical and biological treatment of pharmaceutical wastewater by the activated sludge process was performed in an oxidation ditch. The physicochemical study using different coagulants revealed that all the coagulants used are not effective and their doses required were very high for COD reduction. In the biological oxidation study, it was found that the wastewater could be processed at all organic loadings and phenol concentrations encountered in wastewater. The yield coefficient and decay coefficient were 0.75 (COD basis) and 0.01 day^?1 (COD basis), respectively.     

Nonlinear mixing of electromagnetic waves in plasmas

Recently, a strong research effort has been focused on applications of beat waves in plasma interactions. This research has important implications for various aspects of plasma physics and plasma technology. This article reviews the present status of the field and comments on plasma probing, heating of magnetically confined and laser plasmas, ionospheric plasma modification, beat-wave particle acceleration, beat-wave current drive in toroidal devices, beat wave-driven free-electron lasers, and phase conjugation with beat waves.     

Natural language processing

Natural language processing (NLP) is the study of mathematical and computational modeling of various aspects of language and the development of a wide range of systems. These include spoken language systems that integrate speech and natural language; cooperative interfaces to databases and knowledge bases that model aspects of human-human interaction; multilingual interfaces; machine translation; and message-understanding systems, among others. Research in NLP is highly interdisciplinary, involving concepts in computer science, linguistics, logic, and psychology. NLP has a special role in computer science because many aspects of the field deal with linguistic features of computation and NLP seeks to model language computationally.     

Effects of soybean genotype and growing location on oil and fatty acids in tofu

Soyfood products like tofu are becoming popular among American consumers due to health benefits. In order to increase production to meet consumer demands, it is imperative that factors that effect quantity and quality of tofu be characterized. The present study was conducted to determine the effects of soybean genotypes and growing locations on contents of oil and fatty acids in tofu which was prepared from twelve soybean genotypes (BARC-8, BARC-9, Enrei, Hutcheson, MD86-5788, Nakasennari, S90-1056, Suzuyutaka, V71-370, V81-1603, Ware, and York) grown at three southern U.S. locations (Huntsville, Alabama; Princess Anne, Maryland; and Petersburg, Virginia) during 1995. The results showed that tofu quality was determined by the soybean genotype. The tofu made from seeds of high seed-protein and low seed-oil genotypes (BARC-8 and BARC-9) resulted in tofu with low contents of oil (15.8 and 11.3 g/100g, respectively) and total saturated fatty acids (2.59 and 160 g/100g, respectively). Tofu made from seeds of conventional grain type genotypes, such as Hutcheson, resulted in higher oil (24.0 g/100g) and total saturated fatty acids (3.80 g/100g) contents in tofu. Effects of growing environment on contents of oil were not significant but tofu made from seeds grown in Alabama had significantly higher content of total saturated fatty acids (3.50 g/100g) as compared to that made from seeds grown in Maryland (2.88 g/100g) or Virginia (2.96 g/100g). Tofu made from seeds of large and medium-seeded genotypes had higher contents of total monounsaturated fatty acids in tofu as compared to that made from small-seeded genotypes. Highly positive correlation existed between contents of oil, 18:1, 18:2, total saturated, and total unsaturated fatty acids in the seeds and their contents in the tofu (+0.80, +0.75, +0.79, +0.62, +0.68, respectively). These results indicated that tofu quality is governed by soybean genotype, seed size and growing location.     

Effects of altitude on circadian rhythm of adult locomotor activity in Himalayan strains of Drosophila helvetica

Background  

We recently reported that the altitude of origin altered the photic and thermal sensitivity of the circadian pacemaker controlling eclosion and oviposition rhythms of high altitude Himalayan strains of Drosophila ananassae. The present study was aimed at investigating the effects of altitude of origin on the pacemaker controlling the adult locomotor activity rhythm of D. helvetica.     

Stability via asynchrony in Drosophila metapopulations with low migration rates

Very few experimental studies have examined how migration rate affects metapopulation dynamics and stability. We studied the dynamics of replicate laboratory metapopulations of Drosophila under different migration rates. Low migration stabilized metapopulation dynamics, while promoting unstable subpopulation dynamics, by inducing asynchrony among neighboring subpopulations. High migration synchronized subpopulation dynamics, thereby destabilizing the metapopulations. Contrary to some theoretical predictions, increased migration did not affect average population size. Simulations based on a simple non-species-specific population growth model captured most features of the data, which suggests that our results are generalizable.