PNAS

In This Issue

Artistic reconstruction of shallow marine faunas from the early Palaeozoic Era of North Dakota, spanning the Early (Left) to Middle (Right) Ordovician Period. Image credit: Franz Anthony (artist). The ...
PNAS

Sustainable separation of rare earth elements from wastes

Our study presents a flash Joule heating (FJH) combined with chlorination (FJH-Cl 2) as an efficient method for rare earth elements (REE) separation and recovery from electronic waste. FJH-Cl 2 ...
PNAS

The ergodicity question when imaging DNA conformation using liquid cell electron microscopy

Assessing the ergodicity of graphene liquid cell electron microscope measurements, we report that loop states of circular DNA interconvert reversibly and that loop numbers follow the Boltzmann ...
PNAS

Correction for Bonetti et al., Decoding the elite soccer player’s psychological profile

The authors note that they incorrectly stated in the following sections that two-sample t tests were computed: in the legend for Fig. 2; in Results, the first sentence under Cognitive and Personality ...
PNAS

Freezing enhances CO2 mineralization in Ca2+-containing solutions

Contributed by Joseph S. Francisco; received June 26, 2025; accepted September 12, 2025; reviewed by Jeffrey E. Dick and Shutao Wang ...
PNAS

In This Issue

Number 1A, 1948 by Jackson Pollock is an iconic example of the artist’s action painting technique. The red and yellow pigments used in the painting have been previously identified, but the painting ...
PNAS

An uphill struggle for tropical forest trees

An uphill struggle for tropical forest trees ...
PNAS

Remembrance of phytoplankton’s past

Remembrance of phytoplankton’s pastNote: 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 immediately ...
PNAS

Mesozoic atmospheric CO2 concentrations reconstructed from dinosaur tooth enamel

Air-breathing vertebrates incorporate a fraction of isotopically anomalous air O2 in their body water. The 17O isotope anomaly of air O2 (expressed as Δ’17Oair) is related to atmospheric CO2 concen ...
PNAS

A STOCHASTIC MODEL OF STEM CELL PROLIFERATION, BASED ON THE GROWTH OF SPLEEN COLONY-FORMING CELLS

To address the lack of human cell-based models incorporating all six of the major brain cell types together, which are critically needed to mimic features of brain pathobiology and accelerate ...
PNAS

Rate enhancement of bacterial extracellular electron transport involves bound flavin semiquinones

Extracellular redox-active compounds, flavins and other quinones, have been hypothesized to play a major role in the delivery of electrons from cellular metabolic systems to extracellular insoluble ...
PNAS

A new invariant of 4-manifolds

All known 4-manifolds invariants cannot distinguish a possible counterexample to the smooth 4-dimensional Poincare Conjecture from the standard 4-sphere. The L invariant, defined in this paper, can do ...