Day-of-the-Week Effects in the Long-Run Performance of Initial Public Offerings

This study examines the influence of day-of-the-week patterns in security returns on long-run IPO underperformance. Comparisons are made between the IPOs in Ritter's [20] database, and a constructed set of matching firms based on SIC code and size, using NYSE, AMEX, and NASDAQ securities. It is found that virtually all of the IPO underperformance occurs on Mondays and Tuesdays and that the degree of underperformance significantly differs from other days. Thus, a common explanation may exist for the general day-of-the-week pattern in security returns and IPO long-run underperformance.     

From Phillips curve to wage curve

Summary In most traditional macroeconomic models for The Netherlands the wage equation is specified by a Phillips curve, in which wage growth is negatively related to the unemployment rate. This paper shows, however, that wage formation can better be described by the so-called wage curve, in which the wage level, instead of wage growth, depends negatively on the unemployment rate.The author thanks S.K. Kuipers and D.A.G. Draper and other colleagues of the Central Planning Bureau for their useful comments.     

Preliminary studies using hybrid mediated electrochemical oxidation (HMEO) for the removal of persistent organic pollutants (POPs).

This study investigates the hybrid mediated electrochemical oxidation (HMEO) technology, which is a newly developed non thermal electrochemical oxidation process for organic destruction. A combination of ozone and ultrasonication processes to the mediated electrochemical oxidation (MEO) process is termed as hybrid mediated electrochemical oxidation. The electrochemical cell was developed in this laboratory. In the present study, several organic compounds, such as phenol, benzoquinone and ethylenediaminetetraacetic acid (EDTA), were chosen as the model organic pollutants to be destructed by the hybrid process. The organic destruction was monitored based on the CO2 generation and total organic carbon (TOC) reduction. The HMEO process was found to be extremely effective in the destruction of all the target organics chosen in this study. The information obtained from this study will provide an insight in adopting this technique for dealing with more recalcitrant organics (POPs).     

Degradation of wine industry wastewaters by photocatalytic advanced oxidation.

Wine industry wastewaters contain a high concentration of organic biodegradable compounds as well as a great amount of suspended solids. These waters are difficult to treat by conventional biological processes because they are seasonal and a great flow variation exists. Photocatalytic advanced oxidation is a promising technology for waters containing high amounts of organic matter. In this study we firstly investigated the application of H2O2 as oxidant combined with light (artificial or natural) in order to reduce the organic matter in samples from wine industry effluents. Secondly, we studied its combination with heterogeneous catalysts: titanium dioxide and clays containing iron minerals. The addition of photocatalysts to the system reduces the required H2O2 concentration. Although the H2O2/TiO2 system produces higher efficiencies, the H2O2/clays system requires a H2O2 dosage between three and six times lower.     

Detection of fatty acid beta-oxidizing syntrophic bacteria by fluorescence in situ hybridization.

A new 16S rRNA-targeted oligonucleotide probe, specific for the cluster of fatty acid beta-oxidizing syntrophic bacteria of the family Syntrophomonadaceae was designed for fluorescence in situ hybridization. This probe was evaluated with target as well as non-target cultures. Moreover this probe was assessed with butyrate and oleate degrading enrichment cultures and methanogenic sludges from full-scale plants. The results showed that the probe revealed the presence of fatty acid beta-oxidizing syntrophic bacteria in some of the samples analyzed. However, cell quantification was possible only in enrichment cultures and in a flocculent sludge from a reactor that treats lipid-rich wastewaters, but not in methanogenic granular sludges from upflow anaerobic sludge blanket reactors.     

Equity‐Based Compensation for Employees: Firm Performance and Determinants

I examine the effect of employee equity‐based compensation (EBC) on firm performance and the determinants of EBC. Using two samples, I find that firms have come to rely more heavily on EBC than in the past. For both samples, I document a significant, positive relation between Tobin's q and the percentage of employee compensation that is equity based. For accounting returns, I find a positive relation with the earlier sample. However, for the later sample I find that greater use of EBC leads to lower levels of future accounting returns. I also find that the determinants of the proportion of EBC are different between the two samples.     

Rapid and comprehensive indicator for evaluation of performance of treatment processes and of river waters.

Naturally occurring UV active compounds, commonly present in almost all source waters, can be rapidly monitored by their ultraviolet absorbance at 260 nm (E260). Herein, the extent of correlation between the E260 and the removal efficiency of the hazardous contaminants, endocrine disrupters and dioxins, were investigated using various treatment and river source waters. The detection of various types of hazardous contaminants using sophisticated analytical methods, such as high resolution gas chromatography (HRGC)/high resolution mass spectrometry (HRMS) and high performance liquid chromatography (HPLC)/inductively coupled plasma (ICP)/mass spectrometry (MS), as well as various short-term bioassays, can require hours or even days for results to be obtained. The removal of the E260 correlated well with those of individual contaminants, such as endocrine disruptor chemicals and dioxins, with the various treatment processes employed. In the plots of the endocrine disrupters against the DOC/E260, a correlation was found with the endocrine activity of the Korean/Japanese river waters employed in this study.