We’ve all known for a long time that eating fast food is bad for you. It’s greasy, fatty, high in sodium and the calorie count is obscene. Now comes news that even the packaging that food comes in might be dangerous to your health.

A new study found dangerous chemical compounds in almost half of the 400 fast food containers it tested from 27 fast food franchises. Packaging tested in this study came from the Big Four: McDonald’s, Chipotle Mexican Grill, Starbucks and Yum! Brands, Inc., which operates Taco Bell, KFC, Pizza Hut and WingStreet.

The substances in question are perfluorinated chemicals (PFCs). That’s the same stuff that once was used to make Dupont’s Teflon before it had to be removed from the market. It’s also used in carpeting, furniture, clothing and cosmetics because of its water-repellant and stain-resistant qualities. We’re exposed to it every day.

A researcher in the College of Arts and Sciences is providing fresh insights into the “Great Oxidation Event” (GOE), in which oxygen first appeared in the Earth’s atmosphere more than 2.3 billion years ago.
 

The search for life beyond Earth starts in habitable zones, the regions around stars where conditions could potentially allow liquid water – which is essential for life as we know it – to pool on a planet’s surface. New NASA research suggests some of these zones might not actually be able to support life due to frequent stellar eruptions – which spew huge amounts of stellar material and radiation out into space – from young red dwarf stars.

University of Pennsylvania researchers are now among the first to produce a single, three-atom-thick layer of a unique two-dimensional material called tungsten ditelluride. Their findings have been published in 2-D Materials.

Unlike other two-dimensional materials, scientists believe tungsten ditelluride has what are called topological electronic states. This means that it can have many different properties not just one.

The energy supply to Longyearbyen, midway between continental Norway and the North Pole, is a hot topic in the climate debate.

Longyearbyen is the largest settlement and the administrative centre of Svalbard, a Norwegian archipelago in the Arctic Ocean. Today, Longyearbyen obtains its electric power and district heating from its coal power plant, the only one in Norway.

America’s appetite for Greek yogurt has skyrocketed over the past decade. But for every container of Greek yogurt consumed, you could fill two or three more with the acid whey it produces. The cover story in Chemical & Engineering News (C&EN), the weekly newsmagazine of the American Chemical Society, takes a look at the interesting ways scientists are making use of the byproduct.

Thwaites Glacier on the edge of West Antarctica is one of the planet’s fastest-moving glaciers. Research shows that it is sliding unstoppably into the ocean, mainly due to warmer seawater lapping at its underside.

But the details of its collapse remain uncertain. The details are necessary to provide a timeline for when to expect 2 feet of global sea level rise, and when this glacier’s loss will help destabilize the much larger West Antarctic Ice Sheet. Recent efforts have used satellites to map the underlying terrain, which affects how quickly the ice mass will move, and measure the glacier’s thickness and speed to understand the physics of its changes.

All known black holes fall into two categories: small, stellar-mass black holes weighing a few Suns, and supermassive black holes weighing millions or billions of Suns. Astronomers expect that intermediate-mass black holes weighing 100 - 10,000 Suns also exist, but so far no conclusive proof of such middleweights has been found. Today, astronomers are announcing new evidence that an intermediate-mass black hole (IMBH) weighing 2,200 Suns is hiding at the center of the globular star cluster 47 Tucanae.

A team of scientists from the Energy Department's National Renewable Energy Laboratory (NREL) determined that surface recombination limits the performance of polycrystalline perovskite solar cells.

Considerable research into perovskites at NREL and elsewhere has proved the material's effectiveness at converting sunlight into electricity, routinely topping 20 percent efficiency. The sunlight creates mobile electrons whose movement generates the power but upon encountering defects can slip into a non-productive process. Known as a recombination, this process reduces the efficiency of a solar cell. For the cell to be the most efficient, the recombination must occur slowly.

An international team led by researchers at Nagoya University, along with US and Swiss colleagues, has identified a new type of solar event and dated it to the year 5480 BC; they did this by measuring carbon-14 levels in tree rings, which reflect the effects of cosmic radiation on the atmosphere at the time. They have also proposed causes of this event, thereby extending knowledge of how the sun behaves.

When the activity of the sun changes, it has direct effects on the earth. For example, when the sun is relatively inactive, the amount of a type of carbon called carbon-14 increases in the earth's atmosphere. Because carbon in the air is absorbed by trees, carbon-14 levels in tree rings actually reflect solar activity and unusual solar events in the past. The team took advantage of such a phenomenon by analyzing a specimen from a bristlecone pine tree, a species that can live for thousands of years, to look back deep into the history of the sun.