Formation of knots in mathematical self-avoiding random walks has been extensively studied (10 – 16). In the 1960s, Frisch and Wasserman (10) and Delbruck (11) conjectured that the probability of ...

Edited by* William A. Goddard III, California Institute of Technology, Pasadena, CA, and approved June 26, 2012 (received for review February 27, 2012) ...

The PNAS Editorial Board is made up of NAS members who are active scientists and experts in their fields. On submission, your paper is assigned to an Editorial Board member in one of the 31 NAS ...

Rapid divergence in postmating-prezygotic characters suggests that selection may be responsible for generating reproductive barriers between closely related species. Theoretical models indicate that ...

Major efforts to sequence cancer genomes are now occurring throughout the world. Though the emerging data from these studies are illuminating, their reconciliation with epidemiologic and clinical ...

The western Pacific subtropical high (WPSH) channels moisture from the tropics that underpins the East Asian summer climate. Interannual variability of the WPSH dominates climate extremes in the ...

In our ongoing search for new CB 2 cannabinoid receptor-selective ligands from natural sources, we observed that C. sativa essential oil (5 μg/ml) devoid of the classical cannabinoids strongly ...

Wheat is the most important food crop worldwide, grown across millions of hectares. Wheat yields in the field are usually low and vary with weather, soil, and crop management practices. We show that ...

This article describes a method for fabricating 3D microfluidic devices by stacking layers of patterned paper and double-sided adhesive tape. Paper-based 3D microfluidic devices have capabilities in ...

Open in Viewer RoBMA PSMA model-averaged posterior mean effect size estimates with 95% credible intervals and Bayes factors for the absence of the effect for the combined sample or split by either the ...

Edited by Eric A. Davidson, University of Maryland Center for Environmental Science, Frostburg, MD, and accepted by Editorial Board Member A. R. Ravishankara July 2, 2018 (received for review May 2, ...

We report the mechanism of color production in peacock feathers. We find that the cortex in differently colored barbules, which contains a 2D photonic-crystal structure, is responsible for coloration.