Evidence from the Finnish Twin Registry (e.g., Rose et al., 1988) shows that adult monozygotic (MZ) twins are more similar, within pairs, in personality if the cotwins are presently cohabiting or in frequent contact than if they are seldom in contact. Results of a follow-up study led Kaprio et al. (1990) to conclude that "'changes in social contact between monozygotic cotwins precede (and causa...

Evidence of a positive association between birthweight and IQ has been established in several studies. Analyses of within twin pair differences in birthweight and IQ have been used to shed light on the basis of the association. The strength of this approach is the possibility of controlling for both unmeasured common childhood-environmental factors as well as genetic factors shared by the co-tw...

A meta-analysis of 51 twin and adoption studies was conducted to estimate the magnitude of genetic and environmental influences on antisocial behavior. The best fitting model included moderate proportions of variance due to additive genetic influences (.32), nonadditive genetic influences (.09), shared environmental influences (.16), and nonshared environmental influences (.43). The magnitude o...

OBJECTIVE The purpose of this study was to determine the long-term neurodevelopmental outcome in children after twin-to-twin transfusion syndrome. STUDY DESIGN Maternal and neonatal medical records of all twin-to-twin transfusion syndrome patients who were admitted to our center between 1990 and 1998 were reviewed. Neurologic and mental development at school age was assessed during a home vis...

There are only a few reports of fetal parvovirus infection in the circumstance of a twin pregnancy. We report a case of differential fetal infection following maternal parvovirus B19 infection in a dichorionic twin pregnancy culminating in a dual live-birth. A 32-year-old woman was diagnosed with parvovirus infection following exposure to her infected child at 19 weeks' gestation in a dichorion...

OBJECTIVE To establish the level of birth weight discordance at which perinatal morbidity increases in monochorionic and dichorionic twin pregnancy. METHODS This prospective multicenter cohort study included 1,028 unselected twin pairs recruited over a 2-year period. Participants underwent two weekly ultrasonographic surveillance from 24 weeks of gestation with surveillance of monochorionic t...

AIM: To study the management of second twin and its perinatal outcome in comparison with first twin in Modern Govt. Maternity Hospital. OBJECTIVES: The present study has been undertaken to study the influence of following factors on the perinatal outcome of second twin in comparison with first twin: Chorionicity, Gestational age. Presentation of twins, Mode of delivery, Birth weight, Birth inte...

Dislocation interaction with and accumulation at twin boundaries have been reported to significantly improve the strength and ductility of nanostructured face-centered cubic (fcc) metals and alloys. Here we systematically describe plausible dislocation interactions at twin boundaries. Depending on the characteristics of the dislocations and the driving stress, possible dislocation reactions at ...