Effect of methylphenidate on enhancement of spatial learning by novel alternated dual task.

The novel alternated dual task (ADT) arranged rats to learn Tmaze spontaneous alternation task and radial arm maze (RAM) task alternatively, and by doing ADT, rats could acquire the tasks more easily than non alternated dual task (NADT) group. Also retention capacity of ADT group was significantly more and ADT help to learn a complex task faster than learning it in isolation from other tasks. In the present study effect of methylphenidate (MPD), a mood elevator, known to enhance learning and memory, on ADT procedure is assessed. Also effect of ADT procedure and MPD on spatial learning and memory are compared. Different groups were assigned by administering MPD (intraperitoneal injection at a dose of 3 mg/kg body weight) during different phases of behavioural experiments, and control groups received saline injection. MPD administration increased both acquisition and retention capacities. The amelioration attained for retention of complex task by ADT procedure, could be achieved by NADT rats only by administration of MPD. The influence of ADT procedure on acquisition and retention of TM and RAM tasks were similar to the effects of MPD, especially for the RAM task. MPD at low dose is found to enhance the learning and memory capacity in rats, than deteriorating it, supporting the use of MPD as a drug to treat attention deficit hyperactive disorder. The recent reports suggesting the effect of MPD only on retention and not on acquisition could not be confirmed, as enhancement for both acquisition and retention was found in this study.

Evaluation of allocentric spatial learning in rats using a novel “Alternated Dual Task”.

Allocentric spatial learning can be assessed using popular spontaneous alternation behaviour (SAB) tested with T-maze, and also using radial arm maze (RAM) tasks. But the SAB testing has been reported to have lack of validity as a measure of retention, especially when used as a measure of short term memory. A more complex dual alternated task was designed to clarify whether increasing novelty and alternation factors in a task will increase or decrease the short term and long term memory in rats. Rats were made to learn both T-maze spontaneous alternation task and RAM task alternatively. Another group of rats were made to learn both the task separately without any alternation. And control group of rats were assigned to learn only one type of task. It was found that the group of rats performing “alternated dual task” could acquire the tasks more easily than the control groups and non alternated dual task groups. This enhancement of acquisition was associated only with the complex task (RAM task) among the dual tasks. More over their retention (memory) ability was very significantly enhanced for both the tasks in dual tasks. It can be concluded that, the principle of “alternated dual task” can be made use when a complex task has to be acquired and learned faster by rats; as alternation with simple task enhances the ability of rats to learn and memorize a complex task more efficiently.

Biochemical methane potential of vegetable wastes.

Anaerobic digestion of vegetable waste slurry carried out in the laboratory using 2.5L capacity bottle reactors for 60 days at ambient temperature conditions resulted in a biogas yield of 0.391 L/g of VS fed. The methane content of the biogas generated from the reactors was in the range of 67%-70%. The biochemical methane potential obtained from the laboratory was 0.269 L CH4/g VS added.

Management of waste from stone processing industry.

Characteristics of waste generated in stone processing industries, impact of its current disposal practices and waste recycling potential were assessed by field studies. The physical and chemical characteristics of waste are comparable to construction materials like sand and cement. The environmental issues due to the disposal of waste including that on ambient air quality were identified at respective disposal sites. It was found that the waste can be used to replace about 60% of sand and 10% of cement in concrete. Similarly the waste can replace 40% of clay in clay bricks with affecting its compressive strength.

Methane production from kitchen waste using Escherichia coli.

Escherichia coli (E. coli) strain isolated from biogas plant sludge was examined for its ability to enhance biogas from kitchen waste during solid phase anaerobic digestion. The laboratory experiments were conducted for total solid concentrations of 20% and 22%. Kitchen waste was characterized for physico-chemical parameters and laboratory experiments were conducted with and without E. coli strain. It was found that the reactor with E. coli produced 17% more biogas than the reactors that are operated without E. coli strain.

Ozonation of exhausted dark shade reactive dye bath for reuse.

Exhausted reactive dye bath of dark shades were collected from cotton knit wear dyeing units in Tirupur. Ozonation was conducted in a column reactor system fed with ozone at the rate of 0.16 g/min to assess its efficiency in reducing the color, chemical oxygen demand and total organic carbon. The potential of the decolorized dye bath for its repeated reuse was also analyzed. The results from the reusability studies indicate that the dyeing quality was not affected by the reuse of decolorized dye bath for two successive cycles. Complete decolorization of the effluent was achieved in 60 minutes contact time at an ozone consumption of 183 mg/L for Red, 175 for Navy Blue and 192 for Green shades respectively. The corresponding COD removal was 60%, 54% and 63% for the three shades while TOC removal efficiency was 59%, 55% and 62% respectively. It is concluded that ozonation is efficient in decolorization of exhausted dye bath effluents containing conventional reactive dyes. However, the corresponding removal of COD from the textile effluent was not significant.