منابع مشابه
Evolution: Convergence in Dinosaur Crests
The horned, ceratopsid dinosaurs can be easily split into two major groups based on their cranial structures, but now a new discovery shows that at least one genus 'switched sides' and convergently evolved the form of the other clade.
متن کاملSpurious Crests in Second-Order Waves
Occurrences of spurious crests on the troughs of large, relatively steep second-order Stokes waves are anomalous and not an inherent characteristic of real waves. Here, the effects of such occurrences on the statistics described by the standard second-order stochastic model are examined theoretically and by way of simulations. Theoretical results and simulations indicate that when spurious occu...
متن کاملSagittal Cresting in the South African Australopithecines
The evidence for sagittal cresting, and more generally the position of the temporal lines is reviewed in the South African australopithecine sample. The position of the lines is dependent on both the allometric relation of the masticatory apparatus to cranial size and on individual variation. In the Swartkrans specimens, with generally bigger body size, the influence of allometry predominates, ...
متن کاملExtreme wave crests in space and time
We study the probability distribution of the wave crests under two different scenarios. For sea elevation modelled as a Gaussian random field that evolves in time and when it is modelled at a fixed point by means of a second order model, which is a smooth algebraic function of a vector valued Gaussian process. In the first case, we study the effect of spreading and the role of wave kinematics. ...
متن کاملNuchal translucency in multiple pregnancies.
AIM To evaluate the prevalence of increased nuchal translucency (NT) in multiple pregnancies and its relation to fetal karyotype and pregnancy outcome. METHODS We measured fetal nuchal translucency (NT) in 6,338 women pregnant from 10+3 to 13+6 weeks by ultrasound and evaluated the prevalence of NT=95th centile in 115 multiple pregnancies, including 100 pairs of twins (70 dichorionic and 30 m...
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ژورنال
عنوان ژورنال: Nature
سال: 1954
ISSN: 0028-0836,1476-4687
DOI: 10.1038/1741198a0