Strongest Material Ever Tested

Graphene, praised for its electrical properties, has been proven the strongest known material.

By Katherine Bourzac

Strongest material: By depressing a sharp diamond probe into graphene until it broke, researchers established that the material is the strongest ever tested. This image, an illustration, shows the atomic structure of graphene, which is one atom thick and made up of carbon and hydrogen arranged in a chicken-wire-like mesh. Credit: Jeffrey Kysar, Columbia University

Materials scientists have been singing graphene's praises since it was first isolated in 2005. The one-atom-thick sheets of carbon conduct electrons better than silicon and have been made into fast, low-power transistors. Now, for the first time, researchers have measured the intrinsic strength of graphene, and they've confirmed it to be the strongest material ever tested. The finding provides good evidence that graphene transistors could take the heat in future ultrafast microprocessors.

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How Do Premature Infants Function as Adults?

Risks for medical and social disabilities increased with decreasing gestational age.

Increasing survival of very premature infants has led to concern about adult outcomes. In the largest and longest follow-up study to date, investigators in Norway used linked data from national registries to examine adult outcomes of nearly 1 million infants (gestational age, 23 weeks) who were born without congenital anomalies between 1967 and 1983 and followed through 2003 (age, 20 to 36 years).

The prevalence of virtually all adverse medical and social outcomes, except for measures of criminality, increased with decreasing gestational age. For example, the prevalence of mental retardation was 4.4% among 1822 adults born at 23 to 27 weeks’ gestation compared with 0.5% among those born at term, and the prevalence of cerebral palsy was 9.1% compared with 0.1%, respectively. The prevalence of autistic spectrum disorder (ASD) was 0.6% among those born at 23 to 27 weeks, 0.4% among 2805 adults born at 28 to 31 weeks, and 0.05% among those born at term. Only 25% of adults born at 23 to 27 weeks received university degrees versus 35% of adults born at term. The prevalence of low job-related income also increased with decreasing gestational age. Gestational age was not associated with sentencing for violent crimes or drug felonies.

Comment: These data reinforce that primary care providers should be vigilant about detection of ASD (JW Pediatr Adolesc Med May 28 2008) and mental retardation among children who are born very prematurely. The study also suggests that, although very premature infants have poorer medical and economic outcomes than their peers, most function well as adults. Reassuringly, no differences emerged in any measure of criminality.

— Howard Bauchner, MD

Published in Journal Watch Pediatrics and Adolescent Medicine July 16, 2008

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