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Zinc (Zn 2+ ) is an integral component of many proteins and has been shown to act in a regulatory capacity in different mammalian systems, including as a neurotransmitter in neurons throughout the brain. While Zn 2+ plays an important role in modulating neuronal potentiation and synaptic plasticity, little is...

Recent lichenological investigations of Fox Hills Formation sandstone outcrops in Colorado resulted in the discovery of three populations that represent an undescribed member of the Lecanora dispersa group (录Myriolecis). This new species is different from all others in the group in its production of usnic acid, which yields apothecia that...

One of the challenges of the 21st century is creating a sustainable economy that is able to serve the needs of a growing population with the decreasing supply of natural resources. In addition to alternative energy sources, renewable economy concerns production of materials and chemicals. The chemical and polymer industries...

Advective partial differential equations can be used to describe many scientific processes. Two significant sources of error that can cause difficulties in inferring parameters from experimental data on these processes include (i) noise from the measurement and collection of experimental data and (ii) numerical error in approximating the forward solution...

Numerous diseases, including those of the heart, are characterized by increased stiffness due to excessive deposition of extracellular matrix proteins. Cardiomyocytes continuously adapt their morphology and function to the mechanical changes of their microenvironment. Because traditional cell culture is conducted on substrates that are many orders of magnitude stiffer than...

A 2015 study found that 鈥渟ocial inequality鈥� across a range of disciplines was so bad that just 25 percent of Ph.D. institutions produced 71 to 86 percent of tenured and tenure-track professors, depending on field. The effect was more extreme the farther up the chain the researchers looked, based on...

What matters more to a scientist鈥檚 career success: where they currently work, or where they got their Ph.D.? It鈥檚 a question a team of researchers teases apart in a new paper published in PNAS . Their analysis calls into question a common assumption underlying academia: that a researcher鈥檚 productivity reflects...

Range expansions are crucibles for rapid evolution, acting via both selective and neutral mechanisms. While selection on traits such as dispersal and fecundity may increase expansion speed, neutral mechanisms arising from repeated bottlenecks and genetic drift in edge populations (i.e. gene surfing) could slow spread or make it less predictable...

Musical tastes reflect our unique values and experiences, our relationships with others, and the places where we live. But as each of these things changes, do our tastes also change to reflect the present, or remain fixed, reflecting our past? Here, we investigate how where a person lives shapes their...

For over 25 years, imaging of DNA by atomic force microscopy has been intensely pursued. Ideally, such images are then used to probe the physical properties of DNA and characterize protein鈥揇NA interactions. The atomic flatness of mica makes it the preferred substrate for high signal-to-noise ratio (SNR) imaging, but the...