Ontogenic development of adenylcyclase and phosphodiesterase in rat brain

The activities of adenylcyclase (AC) and phosphodiesterase (PDE) were determined in cerebral cortex of rats of 1 day to 18 months of postnatal age. The activity of dopamine-sensitive and serotonin-sensitive adenylcyclase was also determined in young and old rat brain. AC increased with age and attained a maximum at about 12 weeks of life which plateaued down at 5 months and remained unchanged in the later stages of life. Similarly PDE increased upto 15 weeks which later attained plateau. Dopamine-sensitive AC was not different between young and old rats. However, serotonin-sensitive AC was significantly more in old rats than in young rats. The increase in AC and PDE activity with aging is not only due to increase in protein content but might also be due to increase in cells rich in these enzymes.     

An Evaluation of the Point-of-Care Analyzer,i-Smart 30, for Measurement of Electrolytes

Analytical functioning of a point-of-care analyzer, i-Smart 30 (i-sens: Seoul, South Korea), for electrolyte quantification was investigated at Sant Parmanand Hospital, a tertiary-care hospital in Delhi, India. Samples that were received for electrolyte assay were assayed, double-blinded for their Na and K level using the arterial blood gas analyzer, the ABL 555 (Radiometer, Copenhagen) and the i-Smart 30 electrolyte analyzer. There was satisfactory correlation between the results obtained with the two analyzers with an encouraging bias, standard deviation and the 95 % limits of agreement between the data generated for Na and K levels. The performance of the i-Smart 30 would be satisfactory during the point-of-care measurements of Na and K levels in emergency rooms and clinical laboratories with inadequate infrastructure only if its day-to-day performance was monitored to ensure reliability of the generated reports.     

Work–family balance: perspectives from higher education

The article examines different types of work–family pressures amongst people working within the Australian university sector. We were specifically interested in work–family experiences between domestic and migrant Australians. Among the major findings, domestic Australians experience greater levels of work–family imbalance across most of the measures used. Limitations and implications for future research are discussed.     

No Downturn Here: Tracking E‐business Programs in Higher Education*

As the fortunes of e‐businesses fluctuate, what is the state of e‐business educational offerings? The present study attempted to explore this question by investigating the number and nature of e‐business programs available in colleges and universities. Results were compared to previously published findings on e‐business education. Data were collected from program web sites. Master's and bachelor's degree programs based in North America and elsewhere in the world were examined. Despite the “dot‐bomb” economy, the present data suggested large increases in all foreign and North American bachelor's programs between the start of the fall semester of 2000 and November 2001. The number of North American master's programs appeared to increase dramatically during the year 2000 and at a lesser rate afterward. Findings also suggested that bachelor's and foreign master's programs involved more technical e‐business courses than the North American master's programs. The educational and economic factors possibly underlying these trends are discussed.     

Symmetries and conservation laws in classical and quantum mechanics 1. Classical mechanics

We describe the connection between continuous symmetries and conservation laws in classical mechanics. This is done at successively more sophisticated levels, bringing out important features at each level: the Newtonian, the Euler-Lagrange, and the Hamiltonian phase-space forms of mechanics. The role of the Action Principle is emphasised, and many examples are given.     

A metric measure for direct comparison of competing models in covariance structure analysis

Comparing the fit of alternative models has become a standard procedure for analyzing covariance structure analysis. Comparison of alternative models is typically accomplished by examining the fit of each model to sample data. It is argued that rather than using this indirect approach, one should do direct comparisons of the similarities and differences among competing models. It is shown that among the existing good‐ness‐of‐fit indexes, the root mean square residual (RMSR) is the only one that can be used for this purpose. However, the RMSR fails to satisfy some important statistical desiderata. Rao's Distance (RD), an alternate measure, is shown to overcome this limitation of RMSR. The preference for RD over RMSR for model comparisons is illustrated through a detailed analysis of a particular sample of multitrait‐multimethod data. A simulation study conducted to empirically investigate the sampling behavior of RD reveals that the true orderings of intermodel proximities are recovered (on average) with a fair degree of accuracy.     

Experimental Validation of Antidiabetic Potential of <Emphasis Type="Italic">Cayratia trifolia</Emphasis> (L.) Domin: An Indigenous Medicinal Plant

The present study was undertaken to evaluate antidiabetic and antioxidant activities of Cayratia trifolia root extract against streptozotocin induced diabetes in experimental rats to scientifically validate its use against diabetes in some parts of India. Ethanolic extract, showing the highest activity in in vitro experiments, was prepared in saline and administered orally to streptozotocin induced albino Wistar diabetic rats for 21 days. Biochemical parameters liver and muscles glycogen and in vivo antioxidant activity in normal, diabetic control, standard (metformin) and treated animals were determined and compared. Attempt was made to isolate, purify and characterize one of the major secondary metabolites in extract by range of chromatographic and spectroscopic techniques. Treatment of streptozotocin induced diabetic rats with ethanolic root extract (500 mg/kg) caused significant (P < 0.01) reduction in blood glucose (312–178 mg/dL), increase in body weight (181–219 g) and serum insulin (1.28–2.26 IU/dL). It also maintained lipid profile and tests of liver and kidney functions within normal range as compared to diabetic control rats and almost at par with standard drug metformin. The oxidative stress induced decline in glutathione and catalase in liver and kidney tissues showed recovery nearly to normal level as a function of treatment. The GC–MS profile of the extract showed relatively high concentration of β-sitosterol which was characterized by different spectroscopic and chromatographic techniques. The result scientifically and comprehensively validate the reported use of roots of this indigenous plant against diabetes. A strong antioxidant activity of the ethanolic root extract suitably compliments the antidiabetic effect.