*Learning from fish to develop new materials*

Bulletproof uniforms and space suits impervious to micro-meteorites are two of the potential applications for new materials developed at the Technion-Israel Institute of Technology.

Fish (illustrative) (photo credit: ING IMAGE/ASAP)
Fish (illustrative)
(photo credit: ING IMAGE/ASAP)
Bulletproof uniforms and space suits impervious to micro-meteorites are two of the potential applications for new materials developed at the Technion-Israel Institute of Technology’s faculty of aerospace engineering.
These are two of the possible Technion applications for new complex material, according to an article in a technology journal. These materials were developed by Assistant Prof. Stephan Rudykh, head of mechanics at the soft materials lab.
“Flexibility and strength are considered as usually competing properties; as one increases the other decreases. In general, this is true, but in my research I am trying to create materials that will be both flexible and strong (with respect to their penetration resistance),” Rudykh said.
Starting out as a theorist, Rudykh started to experiment with various formulas after being exposed to the world of 3D printing during his post-doctoral work at the Massachusetts Institute of Technology. He specializes in creating complex soft materials.
“Suddenly I could make the materials that I was designing,” he said, “and then check if their properties match my theoretical projections. Now, too, with these materials, which are flexible and relatively durable against penetration, I can run trials on the models I print.” Rudykh’s research is a joint effort between the Technion and MIT.
He joined the Technion’s faculty as an assistant professor straight from his post-doctoral studies. His research has already been published in leading journals such as Physical Review Letters, and his most recent article was published in Soft Matter.
The inspiration for Rudykh’s development of the new strong and flexible materials comes from fish.
“They are flexible creatures but are protected by hard scales. Their “secret” is the combination of the scales and the soft tissue beneath them, and that is what I tried to mimic here. The materials that I am designing are also made of two layers – one soft (the body) and the other (scales) constitutes the ‘armor.’ These two components provide the combined property of ‘protecto-flexibility’ that we want.”
When asked about possible applications, Rudykh is very cautious.
“My job is not to develop applications but rather to design the material, and my focus at present is the optimization of the material. If, for example, we were talking about army uniforms or a space suit against micro-meteorites, then there are areas such as the chest that need hardly any flexibility and other areas such as the elbow, where flexibility is essential.”
Rudykh stressed that it’s extremely challenging to completely counteract the inverse relationship between flexibility and strength, but said that it is possible to play with the trade-off between them.
“I have managed to increase the penetration resistance by a factor of 40, while reducing flexibility by only a factor of five, and that opens a great many options. Concerning army uniforms or space suits, the idea is to create a tailor- made fabric based on the soldier’s body type and of course the conditions he will be facing. For example, we can think about protection of spacemen against space radiation by incorporating protective materials into the microstructure of the flexible composites.”
“It must be a full moon” is a common refrain when things appear more hectic than usual. The moon is blamed even when things get crazy at hospital emergency rooms or delivery wards.
“Some nurses ascribe the apparent chaos to the moon, but dozens of studies show that the belief is unfounded,” said planetary astronomy Prof. Jean-Luc Margot of the University of California at Los Angeles. Of course, the moon does not influence the timing of human births or hospital admissions, according to Margot’s new research that confirms what scientists have known for decades. The study illustrates how intelligent and otherwise reasonable people develop strong beliefs that, to put it politely, are not aligned with reality.
The absence of a lunar influence on human affairs has been demonstrated in the areas of automobile accidents, hospital admissions, surgery outcomes, cancer survival rates, menstruation, births, birth complications, depression, violent behavior and even criminal activity, Margot wrote in the journal Nursing Research.
Even though a 40-year-old UCLA study demonstrated that the timing of births does not correlate in any way with the lunar cycle, the belief in a lunar effect has persisted. A 2004 study in a nursing journal, for example, suggested that the full moon influenced the number of hospital admissions in a medical unit in Barcelona.
But Margot identified multiple flaws in the data collection and analysis of the 2004 research. By re-analyzing the data, he showed that the number of admissions was unrelated to the lunar cycle. “The moon is innocent,” Margot said.
So why do the erroneous beliefs live on in spite of the evidence? Margot cited what scientists refer to as the “confirmation bias” – people’s tendency to interpret information in a way that confirms their beliefs and ignore data that contradict them. When life is hectic on the day of a full moon, many people remember the association because it confirms their belief. But hectic days that do not correspond with a full moon are promptly ignored and forgotten because they do not reinforce the belief. Margot said the societal costs of flawed beliefs can be enormous.
In just one current example, the recent measles outbreak appears to have been triggered by parents’ questionable beliefs about the safety of the measles vaccine.
“Vaccines are widely and correctly regarded as one of the greatest public health achievements, yet vaccine-preventable diseases are killing people because of beliefs that are out of step with scientific facts,” Margot said.
A willingness to engage in evidence-based reasoning and admit that one’s beliefs may be incorrect will produce a more accurate view of the world and result in better decision-making, Margot said. “Perhaps we can start by correcting our delusions about the moon, and work from there,” he concluded.