Does being born big confer advantages?

Does being born big confer advantages?

when comparing Aboriginal communities to the majority population, as Wassimi and colleagues point out in their study of perinatal and postneonatal mortality by birthweight. In a step toward understanding the higher infant mortality among First Nations communities, the authors tackled the interesting question of whether there are survival advantages to large-for-gestational-age birthweight. In o...

Asteroids were born big

How big were the first planetesimals? We attempt to answer this question by conducting coagulation simulations in which the planetesimals grow by mutual collisions and form larger bodies and planetary embryos. The size frequency distribution (SFD) of the initial planetesimals is considered a free parameter in these simulations, and we search for the one that produces at the end objects with a S...

The Advantages of Being Vectorlike

Consider an asymptotically free gauge theory with global symmetry group G. At short distances this gauge theory allows a perturbative definition. One fundamental question at long distances relates to how the symmetry group G is realized in the vacuum. Virtually no progress has been made in answering this question from first principles in QCD, the gauge theory responsible for all hadronic and nu...

Does advanced maternal age confer a survival advantage to infants born at early gestation?

BACKGROUND Recent studies have shown that older mothers who deliver at preterm gestation have lower neonatal mortality rates compared with younger mothers who deliver at preterm gestation. We examined the effect of maternal age on gestational age-specific perinatal mortality. METHODS We compared fetal, neonatal and perinatal mortality rates among singleton births in the United States, 2003-20...

Planetesimals Born Big by Clustering Instability?