Journal Club

Highlighting recently published papers selected by Academy members

Author Archives: pnas

Differences between viewing light and dark explain old optical illusion

Astronomers and physicists starting with Galileo noticed centuries ago that when one looks at celestial objects — bright objects on a dark background — they appear to be too large. Now scientists have discovered the brain mechanisms underlying this effect. … Continue reading

Categories: Neuroscience | Leave a comment

Liquid metal powers a microfluidic pump

Increasingly researchers are developing lab-on-a-chip devices that can do the work of an entire lab on the area the size of a microchip. Pumps are needed to move tiny amounts of fluid from one chamber to another within these microfluidic … Continue reading

Categories: Applied Physical Sciences | Leave a comment

New class of polyhedra discovered

Geometric forms have fascinated mathematicians since ancient times. Now researchers in California say they have discovered a new class of polyhedron that may already exist in nature and could help lead to novel buildings and other kinds of artificial structures. … Continue reading

Categories: Biophysics and Computational Biology | Mathematics | Leave a comment

Engineered nanomaterials grow smaller and stronger

Materials scientists have a few options for making lighter, yet stronger materials: improve the strength, lower the density, or both. But at a certain point, it’s tough to get much much stronger without added bulk. Jens Bauer and his colleagues … Continue reading

Categories: Engineering | Leave a comment

Why mitochondrial mutants accumulate in aging cells

Why do we grow old and die? The question is a scientific conundrum, as well as an existential one. While scientific answers are sparse, two biologists from the Institute for Ageing and Health at Newcastle University believe they’ve found a … Continue reading

Categories: Biochemistry | Tagged , , | Leave a comment

Lowermost mantle more complex than previously thought

The region of earth’s interior known as the lower mantle may be more chemically heterogeneous than previously thought, suggests new research in PNAS Online Early Edition. The interior of the sphere we call home is a veritable layer cake of … Continue reading

Categories: Earth, Atmospheric, and Planetary Sciences | Leave a comment

Platelets as enzyme factories

The body of an average, healthy adult produces more than two hundred billion new platelets every day. The small cell fragments circulate through the blood stream, helping form blood clots and release growth hormones, for only a matter of days … Continue reading

Categories: Medical Sciences | Leave a comment

Adapting to sea level rise cheaper than potential flooding costs

A new study finds that possible global mean sea level rise of up to 4 feet (1.23 meters) by the year 2100 may lead to the flooding of up to 4.6 percent of the global population, in absence of adaptation … Continue reading

Categories: Sustainability Science | 1 Comment

Evidence of ancient migration from Eurasia to Africa

Investigators of human population genetics often assume that migrations in human history have been in the direction away from Africa — from Africa to the Middle East, then on to Europe and East Asia, and then on to the Americas … Continue reading

Categories: Genetics | Leave a comment

Bacteria work together to gather food

Sulfur-oxidizing bacteria living in the still water at the bottom of salt marshes cooperate with one another to pull food in their direction faster than it would arrive through diffusion, researchers report in the Proceedings of the National Academy of … Continue reading

Categories: Applied Mathematics | Microbiology | Leave a comment