Proceedings of the National Academy of Sciences (PNAS)

Earliest evidence of smoke-dried mummification: More than 10,000 years ago in southern China and Southeast Asia

This finding documents smoke-dried mummification of the dead, mostly in tightly bound crouched postures, from archaeological ...
PNAS

DNA-nanotube-induced alignment of membrane proteins for NMR structure determination

The general applicability of solution NMR spectroscopy to structural characterization of intact α-helical membrane proteins has been demonstrated by a number of recent studies. Examples include the ...
PNAS

Rare dental trait provides morphological evidence of archaic introgression in Asian fossil record

Edited by James F. O’Connell, University of Utah, Salt Lake City, UT, and approved June 12, 2019 (received for review May 3, 2019) ...
PNAS

Journal Club

Journal Club posts are short news stories featuring a recent important, timely journal article selected by one of our Journal Club panelists, who are post-doctoral associates and graduate students in ...
PNAS

Dynamical Systems of Continuous Spectra

Dynamical Systems of Continuous SpectraNote: The article usage is presented with a three- to four-day delay and will update daily once available. Due to ths delay, usage data will not appear ...
PNAS

Phonon softening and crystallographic orientation of strained graphene studied by Raman spectroscopy

We present a systematic study of the Raman spectra of optical phonons in graphene monolayers under tunable uniaxial tensile stress. Both the G and 2D bands exhibit significant red shifts. The G band ...
PNAS

Quantum heat engine power can be increased by noise-induced coherence

Open in Viewer (A) Schematic of a photocell consisting of quantum dots sandwiched between p and n doped semiconductors. Open circuit voltage and solar photon energy ℏνh are related by the Carnot ...
PNAS

The water footprint of humanity

Edited by Peter H. Gleick, Pacific Institute for Studies in Development, Environment, and Security, Oakland, CA, and approved December 21, 2011 (received for review June 20, 2011) In formulating ...
PNAS

Rates of change in natural and anthropogenic radiative forcing over the past 20,000 years

Open in Viewer Evolution of atmospheric CO 2 (a), methane (b), and nitrous oxide (c), and sampling intervals (d) over the past 20,000 years. The gray bar denotes the range of the preindustrial, ...
PNAS

Greenhouse gas mitigation by agricultural intensification

Edited by G. Philip Robertson, W. K. Kellogg Biological Station, Hickory Corners, MI, and accepted by the Editorial Board May 4, 2010 (received for review December 9, 2009) The second counterfactual ...
PNAS

US particulate matter air quality improves except in wildfire-prone areas

Wildfires are a major source of fine particulate matter (diameter <2.5 µm; PM 2.5), which is a health hazard. Since the mid-1980s, the total US area burned by wildfires has been increasing, with fires ...
PNAS

Soil warming, carbon–nitrogen interactions, and forest carbon budgets

Soil warming has the potential to alter both soil and plant processes that affect carbon storage in forest ecosystems. We have quantified these effects in a large, long-term (7-y) soil-warming study ...