Three Essays on Pricing and Market Behaviour around Corporate Acts and Information Releases

This dissertation studies pricing and market behaviour around corporate acts and information releases. The issues examined within this thesis are a fundamental part of the functioning of secondary markets and the broader integrity of the financial system. The three essays in this dissertation examine factors related to the efficiency of price adjustment on equity markets in response to new information and the influence of third party certification on initial public offering process. In particular, the speed by which the information contained in corporate earnings announcements is incorporated into equity prices; the behaviour of algorithmic traders around such announcements; and the insights that venture capitalist backing of newly listing companies has for third party investors are comprehensively examined. The outcomes of these studies provide new insights into how equity markets function and, therefore, the findings are relevant for market practitioners, policy makers and the academic community

A simple and economic slide micro-immunoenzymatic (Micro-SIA) test for epidemiological studies of toxoplasmosis

A slide micro-immunoenzymatic assay (micro-SIA) to detectantibodies to non-particulate Toxoplasma gondii antigens is described. This assay allows the diagnosis of toxoplasmosis infection in about 1 hr. Twenty-four determinations can be performed per slide. Five hundred ng of antigen and 5 or 10 µl drop of each reactive are necessary per well. The clear contrast of colours obtained for negative and positive sera after the test is finished, allows direct discrimination of the results. However, it is possible to quantify the results of the reaction using a minireader. Sera dilution cutoff value, determined as themost frequent titre for the general population, is 1:100. The toxoplasma micro-SIA correlates well with indirect immunofluorescence (IIF), its sensitivity is atleast three times as much as IIF. The test has an intra and inter assay variation coefficient of 5.46 per cent and of 6.24 per cent respectively. Sera obtained at random from argentinian people were analyzed and a 56 per cent of infection was found. The main features of the Toxoplasma micro-SIA are its simplicity, sensitivity, reproducibility, and the virtual absence of background making it very suitable for screening tests