OBJECTIVES To determine whether twins in recent cohorts show similar academic performance in adolescence to singletons and to test the effect of birth weight on academic performance in twins and singletons. DESIGN Follow-up study. SETTING Denmark. PARTICIPANTS All twins (n=3411) and a 5% random sample of singletons (n=7796) born in Denmark during 1986-8. MAIN OUTCOME MEASURES Test score...

Aim Several studies have indicated that the cause of the increased birthweight of frozen-thawed embryos was associated with assisted reproductive technology (ART) procedures, such as cryopreservation. In the present study, the mean birthweight of singletons was compared between the ovulatory and hormone replacement therapy (HRT) cycles in order to investigate the primary factor that leads to hi...

The unique intrauterine environment has been proposed to put twins at increased risk of certain cancers compared to singletons, still large population comparisons have generally indicated lower risks in twins. To improve the understanding of potential twin influence on cancer we compared twins to their singletons siblings, to target a unique twinning influence. Singletons from twin families wer...

Salmonella species are important foodborne pathogens that can cause illness and death in humans. The objective of this study was to determine the genetic relatedness of 115 Salmonella strains isolated from ducks and their environment using random amplified polymorphic deoxyribonucleic acid (RAPD). The analysis of Salmonella strains by RAPD produced DNA fingerprints of different sizes for differ...

Research on twin-singleton differences in externalizing and internalizing problems in childhood is largely cross-sectional and yields contrasting results. The goal of this study was to compare developmental trajectories of externalizing and internalizing problems in 6- to 12-year-old twins and singletons. Child Behavior Checklist (CBCL) maternal reports of externalizing and internalizing proble...

There is considerable debate as to whether colour singletons can capture attention in a stimulus-driven manner. In this study, we explore one potential capture enabling condition*low perceptual load. To test this hypothesis, we manipulated perceptual load in a flanker task in which flanking letters sometimes were colour singletons. If low load enhances capture by colour singletons, then colour ...

OBJECTIVES To examine the risk of mortality and major morbidities in extremely preterm multiple gestation infants compared with singletons over time. METHODS This is a retrospective study of 15,402 infants born ≤27 weeks' gestation, admitted to NICUs in the Australian and New Zealand Neonatal Network from 1995 to 2009. Mortality and major morbidities were compared between singletons and multi...

BACKGROUND Recently, concern has risen about poor obstetrical and neonatal outcome of singletons after IVF/ICSI. Because the population of patients receiving single-embryo transfer (SET) resulting in singleton pregnancies is different from the one that would have become pregnant (with a singleton) before SET was introduced, we wanted to investigate whether the outcome of singleton pregnancies a...

Aim of study: The goal the study was to estimate true species richness from Braun Blanquet (BB) scale data.
 Area Yazılı Canyon Nature Park (YCNP) located in Mediterranean Region Turkey.
 Material and methods: A bias-corrected approach adapted based on Good-Turning frequency formula (S_est ) for 9 vegetation plots under three scenarios (Rare are singletons: with 1/1 probability 〖(Sc〗_...

OBJECTIVES This study evaluated the extent to which morbidity and costs at birth were associated with plurality, gestational age, and birth-weight with a sample of twins from a large urban hospital. METHODS Each twin infant was matched to two singleton infants (control [ctrl]-singletons) for payor status and race, and to one singleton infant (gestation [ga]-singleton) for payor status, race, ...