A formula for thermal stability (Tm) prediction of PNA/DNA duplexes.

An empirical formula for thermal stability (T m) prediction of PNA/DNA duplexes has been derived. The model is based on the T m as calculated for the corresponding DNA/DNA duplex employing a nearest neighbour approach, by including terms for the pyrimidine content and length of the PNA to take into account the increased thermostability of PNA/DNA hybrids and the asymmetry of the PNA-DNA heteroduplex. The predictive power of the T m prediction formula was challenged with an independent data set not used for model building.

Quality control in routine chromosome analysis: prediction of total number of bands for the individual case analyzed.

In routine diagnosis it is of importance for each single analysis to provide information about the level of quality at which the chromosomal analysis has been performed. The number of bands counted can be used as a direct criterion for the level of quality. Statistical prediction methods via linear regression were employed in order to predict the total number of bands of a haploid set of the metaphase (TNB) from those of single chromosomes or pairs of chromosomes.

A hypothesis on the abnormal seasonality of schizophrenic births.

The hypothesis is proposed that the abnormal seasonality of schizophrenic births is partly a consequence of seasonal variation of conception and of an associated seasonal variation of risk of premature delivery.