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Shigeyoshi Osaki of Japan’s Nara Medical University has used thousands of strands of spider silk to spin a set of violin strings.

The strings are said to have a “soft and profound timbre” relative to traditional gut or steel strings.

That may arise from the way the strings are twisted, resulting in a “packing structure” that leaves practically no space between any of the strands.

The violin strings will be described in a forthcoming edition of the journal Physical Review Letters.

Shigeyoshi Osaki has been interested in the mechanical properties of spider silk for a number of years.

Shigeyoshi Osaki of Japan's Nara Medical University has used thousands of strands of spider silk to spin a set of violin strings

Shigeyoshi Osaki of Japan's Nara Medical University has used thousands of strands of spider silk to spin a set of violin strings

In particular, Dr. Shigeyoshi Osaki has studied the “dragline” silk that spiders dangle from, quantifying its strength in a 2007 paper in Polymer Journal.

Dr. Shigeyoshi Osaki has perfected methods of obtaining large quantities of this dragline silk from captive-bred spiders and has now turned his attention to the applications of the remarkable material.

“Bowed string instruments such as the violin have been the subject of many scientific studies,” Shigeyoshi Osaki writes.

“However, not all of the details have been clarified, as most players have been interested in the violin body rather than the properties of the bow or strings.”

Dr. Shigeyoshi Osaki used 300 female Nephila maculata spiders – one of the species of “golden orb-weavers” renowned for their complex webs – to provide the dragline silk.

For each string, Dr. Shigeyoshi Osaki twisted between 3,000 and 5,000 individual strands of silk in one direction to form a bundle. The strings were then prepared from three of these bundles twisted together in the opposite direction.

Dr. Shigeyoshi Osaki then set about measuring their tensile strength – a critical factor for violinists wishing to avoid breaking a string in the midst of a concerto.

The spider-silk strings withstood less tension before breaking than a traditional but rarely used gut string, but more than an aluminum-coated, nylon-core string.

A closer study using an electron microscope showed that, while the strings themselves were perfectly round, in cross-section the strands had been compressed into a range of different shapes that all fit snugly together, leaving no space between them.

Dr. Shigeyoshi Osaki suggests that it is this feature of the strings that lends them their strength and, crucially, their unique tone.

“Several professional violinists reported that spider strings… generated a preferable timbre, being able to create a new music,” Shigeyoshi Osaki wrote.

“The violin strings are a novel practical use for spider silk as a kind of high value-added product, and offer a distinctive type of timbre for both violin players and music lovers worldwide.”

 

A British team of physicians have come up with an equation that explains and predicts the shape of a ponytail that could help scientists better understand natural materials, such as wool and fur.

The Ponytail Shape Equation findings have been published in Physical Review Letters journal.

The new equation takes into account the stiffness of hairs, the effects of gravity and the presence of random curliness or waviness.

“It’s a remarkably simple equation,” explained Prof. Raymond Goldstein, who is the Schlumberger Professor of Complex Physical Systems at Cambridge University.

He added that the findings showed how physics could be used to “solve a problem that has puzzled scientists and artists ever since Leonardo Da Vinci remarked on the fluid-like streamlines of hair in his notebooks 500 years ago”.

Prof. Raymond Goldstein worked on the equation with Professor Robin Ball from the University of Warwick and Patrick Warren, from Unilever’s Research and Development Centre.

The Ponytail Shape Equation represents the first scientific understanding of the distribution of hairs in a ponytail, say the researchers

The Ponytail Shape Equation represents the first scientific understanding of the distribution of hairs in a ponytail, say the researchers

The Ponytail Shape Equation represents the first scientific understanding of the distribution of hairs in a ponytail, say the researchers.

It provides new understanding of how a bundle is swelled by the outward pressure which arises from collisions between the component hairs.

Together with a new mathematical quantity known as the Rapunzel Number, the equation can – they say – be used to predict the shape of any ponytail.

It opens the way to a better understanding of materials made up of random fibres, say the researchers.

This will resonate with some in the computer graphics and animation industry, where a realistic representation of hair and fur has proven a tough challenge.

Prof. Raymond Goldstein is presenting the research at the American Physical Society meeting in Boston on 28 February.