The last few decades have shown that analytical chemistry and environmental chemistry are “conjoined twins”. Neither can move significantly forward without the contribution and support of the other discipline. But in their conjoined development both disciplines have contributed much to our knowledge of environmental pollution, to the understanding of environmental processes, and to the developm...

Conjoined twins, the most striking anomaly of monozygosity, have always aroused extensive interest in both the medical community and the general population, owing to their rarity and unusual presentations.1 Craniopagus twins joined at the head are uncommon malformations, found once per 2.5 million live births, and represent only 2% to 6% of conjoined twins.2 In 1977, Fagan3 first reported the p...

The health benefits of breastfeeding are well known. However, less is known about the frequency and duration of breastfeeding in twins. A population-based study of maternal factors associated with the early cessation of breastfeeding in preterm and term twins is reviewed. This is followed by research reviews and news concerning aging in twins, conjoined twin separation and school legislation fo...

Conjoined twins represent a rare but fascinating congenital condition, the aetiology of which remains obscure. Over the past four decades, the paediatric surgeons at Red Cross Children's Hospital have been involved in the management of 46 pairs of conjoined twins, of which 33 have been symmetrical and 12 asymmetrical. Seventeen symmetrical twins have undergone separation with 22 children (65%) ...

In a sample of 157 monozygotic and dizygotic twins, genetic and environmental influences on infant attachment and temperament were quantified. Only unique environmental or error components could explain the variance in disorganized versus organized attachment as assessed in the Ainsworth Strange Situation Procedure. For secure versus nonsecure attachment, 52% of the variance in attachment secur...

Genetically proven identical twin sisters with Alzheimer's disease are reported. Both sisters at the age of fifty years developed a dementing illness. Their mother and maternal grandmother developed at the same age a similar illness. It is suggested that in some cases of familial Alzheimer's disease the condition is inherited by a single mutant gene.

We applied multivariate genetics techniques to a sample of 3,412 monozygotic and dizygotic twins from the United Kingdom and 1,300 monozygotic and dizygotic twins from the United States to examine whether genetic factors account for part of the covariance between the Big Five personality characteristics and the tendency to be an entrepreneur. We found that common genes influenced the phenotypic...

Twin children participating in a longitudinal study were observed at 9, 12, 18, 24, and 30 months of age in two settings: unstructured free play and relatively structured test taking. Behaviors relating to adaptability to the two settings were rated and the scores analyzed for evidence of continuity both across settings and across ages. Age-to-age correlations for the adaptability scores for ea...

The heritability of total plasma testosterone levels, determined from blood samples, was examined in 160 adolescent twin pairs and their parents. Subjects were tested as part of a larger study of cardiovascular risk factors, conducted in Amsterdam. Each subject provided a sample of blood which was assayed to measure testosterone concentrations. Correlations of testosterone in monozygotic twins ...