No abstract

Extracts of Ginkgo biloba and Bacopa monniera have been shown to produce positive effects on cognitive function in healthy subjects. While the exact mechanisms are not known, it has been suggested that antioxidant properties and cholinergic modulation may play a role. In the current study the sub-chronic (2 weeks) and chronic (4 weeks) effects of an extract containing Ginkgo biloba (120 mg) and Bacopa monniera (300 mg) (Blackmores Ginkgo Brahmi) on cognitive function were examined. The study was a randomized, double-blind, placebo-controlled, independent group design in which 85 healthy subjects were allocated to one of two treatment conditions (placebo or combined Ginkgo biloba and Bacopa monniera extract). Testing was conducted at baseline and 2 and 4 weeks post treatment. The results showed that the combined extract relative to placebo did not demonstrate any significant effects on tests investigating a range of cognitive processes including attention, short-term and working memory, verbal learning, memory consolidation, executive processes, planning and problem solving, information processing speed, motor responsiveness and decision making. These findings suggest that at least within the current treatment duration and doses, an extract containing Ginkgo biloba and Bacopa monniera had no cognitive enhancing effects in healthy subjects.

No abstract

We examine the price and volatility reaction around stock dividend ex-dates for an Australian sample, over the period January 1992 to December 2000. We find that price reaction around stock dividend exdates provides positive abnormal returns both prior, and subsequent, to the abolishment of par value of shares in July 1998. When we partitioned the sample into financial, industrial non-financial and mining firms, the price reaction is found to be positive and significant only for industrial non-financial companies. Volatility of daily returns for periods subsequent to ex-dates is significantly greater than corresponding periods prior to announcement dates, while cumulative raw returns subsequent to exdates are significantly lower than periods prior to announcement dates for industrial non-financial companies. The magnitude of the price reaction is statistically significantly related to an increase in the volatility of daily returns and to a reduction in cumulative raw returns subsequent to the ex-dates, for industrial non-financial companies. These findings support buying pressure hypothesis suggested by Dhatt et al . (1994Dhatt et al . ( , 1996. I . I n t r o d u c t i o nIn theory stock dividends (referred to as 'bonus issues' in Australia and New Zealand) do not affect the financial position of shareholders, nor do they improve the financial position of the issuing company. They represent distributions of additional shares, resulting in each shareholder owning a greater number of shares in the issuing company. However, the relative claim of each shareholder on the assets of the company remains unchanged. That is, in theory (absent any potential information effects that will be centred at the earlier announcement date) at the stock dividend ex-date we should observe a value neutral reduction in stock price, that exactly offsets the dilution effect of the increased number of shares outstanding. Thus, once this 'dilution effect' has been taken into consideration, there should be no impact on the returns distribution of stock dividend shares at the ex-date.If capital markets are efficient, any abnormal price reaction should occur at the time of the announcement in response to the information content contained therein. Extensive research has been conducted to examine the impact of stock dividends on share prices around announcement