So, the study looked at 14 Viking burials from the era, definable by the Norse grave goods found with them and isotopes found in their bones that reveal their birthplace. The bones were sorted for telltale osteological signs of which gender they belonged to, rather than assuming that burial with a sword or knife denoted a male burial.
Overall, McLeod reports that six of the 14 burials were of women, seven were men, and one was indeterminable. Warlike grave goods may have misled earlier researchers about the gender of Viking invaders, the study suggests. At a mass burial site called Repton Woods, “(d)espite the remains of three swords being recovered from the site, all three burials that could be sexed osteologically were thought to be female, including one with a sword and shield,” says the study.
“These results, six female Norse migrants and seven male, should caution against assuming that the great majority of Norse migrants were male, despite the other forms of evidence suggesting the contrary. This result of almost a fifty-fifty ratio of Norse female migrants to Norse males is particularly significant when some of the problems with osteological sexing of skeletons are taken into account,”
The solution, Celanovic says, is to design a thermal emitter that radiates only the wavelengths that the PV diode can absorb and convert into electricity, while suppressing other wavelengths. “But how do we find a material that has this magical property of emitting only at the wavelengths that we want?” asks Marin Soljačić, professor of physics and ISN researcher. The answer: Make a photonic crystal by taking a sample of material and create some nanoscale features on its surface — say, a regularly repeating pattern of holes or ridges — so light propagates through the sample in a dramatically different way.
“By choosing how we design the nanostructure, we can create materials that have novel optical properties,” Soljačić says. “This gives us the ability to control and manipulate the behavior of light.”
The team — which also includes Peter Bermel, research scientist in the Research Laboratory for Electronics (RLE); Peter Fisher, professor of physics; and Michael Ghebrebrhan, a postdoc in RLE — used a slab of tungsten, engineering billions of tiny pits on its surface. When the slab heats up, it generates bright light with an altered emission spectrum because each pit acts as a resonator, capable of giving off radiation at only certain wavelengths.
While it looks like a typical silver-colored rollerball pen, this pen’s ink is a solution of real silver. After writing, the liquid in the ink dries to leave conductive silver pathways — in essence, paper-mounted wires. The ink maintains its conductivity through multiple bends and folds of the paper, enabling devices with great flexibility and conformability.
Metallic inks have been used in approaches using inkjet printers to fabricate electronic devices, but the pen offers freedom and flexibility to apply ink directly to paper or other rough surfaces instantly, at low cost and without programming