Preparation of Crosslinked Starch Beads as a Medium for Gel Filtration

Potato starch is dispersed in sodiumhydroxide and fine emulsion is obtained by stirring in liquid paraffin at 80°C. The emulsion is crosslinked with epichlorohydrin in presence of sodium borohydride to obtain thermostable beads. Beads of uniform size were obtained by sedimentation under gravity. Mixtures of proteins such as bovine serum albumin (BSA) and cytochrome c can be separated on columns (Ø 2.5 × 25.0 cm) packed with these beads. The elution profiles are similar to that of Sephadex G-100.     

Evaluation of Generating System Reliability Indices Under Limited Repair Facility

A generating system having n units, where each unit is represented by a 2-state device, will have more than 2n possible states when repair facility of the system is limited, i.e. number of repair crews is less than the number of units. When the number of units failed is more than the number of repair crews available, the most recent failures queue for repairs. This paper gives a general equation to determine the number of system states under limited repair facility and an approximate technique to determine the probabilities of system states and reliability indices of the system.     

Presensitization of microorganisms by acid treatments to low dose gamma irradiation with special reference to Bacillus cereus

Effect of acid presensitization to low dose gamma irradiation on Bacillus cereus in sheep/goat meat stored at refrigeration temperature was assessed. Food grade organic acids (viz. propionic, lactic and acetic acids) were used as presensitizers followed by treatment with 1, 2 and 3 kGy irradiation doses (Co(60)). Two percent acetic acid plus 3 kGy irradiation elicited most effective to lower the total viable count and B. cereus count. Combination of treatments availed to reduce the dose required for elimination of radioresistant B. cereus and also masked the irradiation odour developed due to radiolysis. The study also revealed substantial increase in shelf life of mutton after combination treatment than single treatment without any adverse effect on acceptability of meat.     

Lung tumour incidence in mice treated with hydrazine sulphate

Lung tumour incidence in mice fed with hydrazine sulphate (1.1 mg/day/mouse) was studied in male and female mice of Swiss, Strong "A" and F1 cross of ICRC (female) X C3H (Jax) (male), as well as in C17 males. Swiss strain mice showed 100% lung adenocarcinomas. None of the treated mice of different strains had liver tumours. Hydrazine sulphate also induced adenocarcinomas of lung in Strong "A" and F1 cross of ICRC females X C3H (Jax) males but it produced lymphomas of lung in C17 strain. Female mice of Swiss strain and F1 hybrids showed greater susceptibility to hydrazine sulphate than the males. It was interesting to observe that protein and vitamin B deficiency in the diet shortened the tumour induction period in Swiss strain mice.     

Luminescence of Cu<Superscript>+ </Superscript>in halosulphate phosphor

Ultraviolet photo-excited luminescence from Cu-doped halosulphate phosphors has been investigated. The intense emission of the spectrum is assigned to electronic transitions 3d⁹4s¹ → 3d¹⁰ in Cu⁺ ions. Increase in photoluminescence (PL) peak intensity suggesting that Cu plays an important role in PL emission in the present matrix. However, limited hosts with Cu⁺ as luminescence center were studied due to difficulties in incorporating it in a luminescence form. Cu-doped halosulphate phosphors were synthesized by wet chemical method. X-ray diffraction and PL characterization of phosphors has been reported in this article. The article discusses the luminescence of Cu⁺ and the simple method of incorporation in various new hosts.     

Transient axonal branching in the developing corpus callosum

During development, there is a transient overproduction of axons in the corpus callosum; this overproduction of axons is due, in part, to a transient excess of neurons that send an axon through the corpus callosum. However, transient axonal branching could also contribute to the developmental overproduction of callosal axons. To investigate this possibility, we filled developing callosal axons in the Syrian hamster with the carbocyanine dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (Dil). Light microscopic analysis showed that, indeed, developing callosal axons branch transiently in the hamster: branching was robust on postnatal day 0 (P0) and P3 (P0 = the first 24 hr after birth), less prominent on P6 and P8, and absent by P11. Immature callosal axons branched before or after crossing the midline and at all rostral-caudal and medial-lateral levels within the corpus callosum. The majority of callosal axon collaterals that were contained within individual 100-micron-thick sections were relatively short (mean = 15.1 microns) but some collaterals extended up to approximately 135 microns from the main axon trunk before passing out of the section in which they were observed. Nearly all of the collaterals emanated from the main axon trunk; higher-order collaterals were rare. Some callosal axon trunks had multiple collaterals. Branching callosal axons originated from multiple cortical areas, including area 17. Electron microscopic observations indicated that the processes designated as axon collaterals by light microscopic criteria would have been included in electron microscopic counts of developing callosal axons. Some callosal axon trunks and branches had ultrastructural features that suggested they were degenerating. In cats, developing callosal axons branch on embryonic day 57 (E57; the first 24 hr after conception = E0) and P0. Thus, it is likely that transient branching of immature callosal axons is a generalized feature of mammalian cortical development and that it contributes to the overproduction of callosal axons, albeit perhaps to varying degrees, in multiple species.     

Fault section estimation in power system using Hebb’s rule and continuous genetic algorithm

In this paper a new approach for fault section estimation (FSE) in electrical power system is presented. We propose a procedure to obtain objective function (required for fault section estimation) using the Hebb’s learning rule. The continuous genetic algorithm (CGA) optimization method is then employed to estimate the fault section making use of the objective function. The Hebb’s learning law used in this paper gives, linear algebraic equations, to represent the targets in terms of the status of relays and circuit breakers (CBs). This gives a simple objective function, which leads to reduction in time required by the CGA to identify fault section. The CGA gives an advantage of requiring less storage than binary genetic algorithm (GA). Also the CGA is inherently faster than binary GA.The proposed approach is tested on various systems, and is found to give correct results in all cases. Simulation results for two illustrations have been presented in this paper. The results show that the proposed approach can find the solution efficiently even in case of multiple faults or in case of failure of relays/circuit breakers. A comparison with artificial neural network (ANN) approach is also presented.