A new study uses tree rings to document arroyo evolution along the lower Rio Puerco and Chaco Wash in northern New Mexico.

Five years ago, it was good luck finding a hotel anywhere near the rural areas where natural gas extraction - fracking - was taking place.

The boom in natural gas meant a boom in employment and a boom in hotel rooms to keep workers. The wealth boosted Pennsylvania and other energy-dense states while most of the country remains mired in economic malaise. But over time people buy homes rather than rent hotel rooms and now there may be too many, says hospitality management scholars at Penn State.

"Demand is still high in many of the counties in the Marcellus Shale region, but the occupancy rate is starting to come down," says associate professor Daniel Mount. "The case could be made that this is a sign that hotels were overbuilt."

Miranda is a small, icy moon of Uranus and one of the most visually striking and enigmatic bodies in the solar system.

Despite its relatively small size, Miranda appears to have experienced an episode of intense resurfacing that resulted in the formation of at least three remarkable and unique surface features -- polygonal-shaped regions called coronae. 

These coronae are visible in Miranda's southern hemisphere, and each one is at least 200 km across. Arden corona, the largest, has ridges and troughs with up to 2 km of relief. Elsinore corona has an outer belt that is approx. 80 km wide, relatively smooth, and elevated above the surrounding terrain by approx. 100 m. Inverness corona has a trapezoidal shape with a large, bright chevron at its center.

Researchers at Harvard School of Medicine and the University at Buffalo have discovered a sleep-promoting circuit located deep in the primitive brainstem, only the second "sleep node" identified in the mammalian brain whose activity appears to be both necessary and sufficient to produce deep sleep. 

Writing in Nature Neuroscience, the study demonstrates that fully half of all of the brain's sleep-promoting activity originates from the parafacial zone (PZ) in the brainstem. The brainstem is a primordial part of the brain that regulates basic functions necessary for survival, such as breathing, blood pressure, heart rate and body temperature.