Butterfly-inspired technology to ensure safe currency
New York: Inspired by a butterfly whose wings appear to change colours, researchers from Harvard University have found a way to mimic the colour change using artificial materials to build a new counterfeit-proof material.
The material can be used to make more secure banknotes or passports.
The superthin, transparent material is made of a series of microscopic plates. Each tiny plate, about 18 mm tall, features a ridged edge.
By changing the height size and spacing between the plates or the ridges, the researchers can change how the material diffracts light.
“We thought there could be some benefit for such a unique material in security printing. The material could also coat the solar panels to manipulate how light enters the individual cells,” explained study co-author Mathias Kolle from Harvard.
The male Pierella luna butterfly from Latin America has wings that appear to change colour when looked at from different angles.
The optical trick is possible thanks to tiny scales on its wings that curl slightly upward at the end and diffract light, Live Science reported. (IANS)
Columbus’ departure point authenticated
Madrid: The discovery of objects during excavations at Palos de la Frontera in southwestern Spain has allowed scholars to determine the exact location from where Christopher Columbus’ three ships set off in 1492.
The discovery is of international importance, as it sheds light on one of the most important chapters of history.
For years it had been suspected that the remains of the port’s long-vanished infrastructure was located in the area known as “the trough”, but until Monday, there was no evidence to confirm it, said Juan Manuel Campos, a professor who led the team that made the discovery.
Historical sources say the port comprised a shipyard, a fresh water fountain called La Fontanilla, a pottery works and a reef, Campos said.
Traces of the pottery and the reef were discovered in the most recent excavation, confirming Palos as Columbus’ point of departure.
In 1992 researchers already deduced, through indirect data, that the port was located somewhere in the area known as the “vaguada”, or trough.
But it hasn’t been until now, 24 years later, that archeological excavations led by Campos, professor at the University of Huelva, confirmed the hunch.
The discovery of the pottery has been crucial, since seven ovens have been found that make it a unique example of this type of building in 15th-century Spain, in which ceramics, bricks, tiles, baked goods and lime were produced. But the discovery of the reef is of even greater importance, allowing the experts to determine the exact location of the port. Palos was an “international and prosperous” port from the second half of the 15th-century to the early 16th-century, as these findings attest.
“The reef was the port’s customs area, and it was the place where Columbus negotiated and made the arrangements necessary for the success of his historic voyage,” Campos said. (IANS)
Mirror power! Try on clothes even when shop is closed
London: How about trying on clothes via shop windows even when the shutters are down? This could soon be a reality thanks to new research led by an Indian-origin scientist that uses semi-transparent mirrors in interactive systems.
Professor Sriram Subramanian, Dr Diego Martinez Plasencia and Florent Bethaut from the University of Bristol have built on a mirror’s ability to map a reflection to one unique point behind the mirror independently of the observer’s location.
“So even when the shop is closed, their reflection would be visible inside the shop window and that would enable them to try clothes on using their reflection, pay for the item using a debit/credit card and then have it delivered to their home,” Subramanian explained.
In a museum, people in front of a cabinet would see the reflection of their fingers inside the cabinet overlapping the exact same point behind the glass.
“If this glass is at the front of a museum cabinet, every visitor would see the exhibits their reflection is touching and pop-up windows could show additional information about the pieces being touched,” Subramanian pointed out. Visitors could also interact with exhibits by focusing their eyes on them. According to Subramanian, by directly pointing at the exhibit with their reflection instead of pointing at them through the glass, people could easily discuss the features of the exhibits with other visitors.
“This work offers exciting interactive possibilities that could be used in many situations. Semi-transparent surfaces are everywhere around us, in every bank and shop window,” added Dr Diego Martinez, researcher in Human-Computer Interaction in the Bristol Interaction and Graphics (BIG) group.
The possibility to blend together the spaces in front and behind the semi-transparent mirror could mean a whole new type of interactive experience, researchers concluded. The research paper is to be presented at ACM UIST 2014 “one of the world’s most important conferences on human-computer interfaces” this month. (IANS)