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Scientists observe metal repairing itself for the first time. Could Terminator robots be on the horizon?

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For the first time, scientists have spotted metal healing itself after cracking — an observation that could pave the way for the creation of structures and robots capable of mending themselves.

But for those worrying about the rise of real-life Terminator robots — don’t: The newly discovered mechanism only works on a few metals and on incredibly small scales — at least, for now.

“Of course, there are lots of industries whose product engineers would love to translate this finding into intentional engineering approaches to create metals that automatically heal themselves in our structural applications,” lead-author Brad Boyce, a materials scientist at Sandia National Laboratories in Albuquerque, New Mexico, told Live Science. “Self-healing metals could be useful in a wide range of applications from airplane wings to automotive suspensions.”

Scientists had previously assumed that metals were incapable of repairing themselves, but the new discovery, made inadvertently by scientists studying nanometer-size chunks of platinum and copper, overturns this conclusion.

Metals sustain fatigue damage from repeated stress or motion, creating growing webs of microscopic cracks that can lead to catastrophic failures of jet engines, bridges and other vital structures.

But not all materials break under repeated strain: Some modern polymers and even ancient Roman concrete have been shown to repair their microcracks over time.

In 2013, a team of researchers used computer models to show that metals may also be capable of performing the healing trick, but they were not able to study metals at the tiny scales necessary so couldn’t get any real-world evidence.

In the new study, published July 19 in the journal Nature, scientists investigated how nano-size metal pieces respond to repeated stress using a device called a transmission electron microscope. The device applied an extremely small force — equivalent to the stomping of a mosquito’s leg — in the form of 200 tiny tugs to the metals every second.

In two of the metals, copper and platinum, cracks appeared and grew throughout the materials. But then, after 40 minutes, the metals fused themselves back together, leaving no trace of the cracks.

According to Boyce, the explanation for this miraculous self-repair lies in a process called “cold welding.”

“In a nutshell, at the nanoscale, the local conditions around the crack tip are such that the two crack flanks are compressed into one another,” Boyce said. “When they contact, the two flanks heal back together in a process that metallurgists refer to as ‘cold welding’. This process does not appear to happen all the time, but only in cases where the local conditions induce crack flank contact.”

How widely implementable the researchers’ new observations are remains unknown. Firstly, to observe the cold welding processes, scientists isolated the metals within a vacuum so that no atmospheric atoms interfered with the equipment. This means they don’t yet know if the process works only in a vacuum or not.

Similarly, the range of possible metals that can self-repair is also unknown. The scientists only observed cold welding in platinum and copper, but whether commonly used structural metals such as steel also perform the feat is yet to be seen.

There is also the problem of scaling. The metals used were tiny and highly ordered in their structures; whether large metals can be coaxed into healing too isn’t known.

Nonetheless, the scientists are cautiously optimistic that their discovery could lead to fundamental changes in the way we build and design metal structures for durability, and could even have applications for spaceflight, where atmospheric particles are not a problem.

“Actually, we believe that this process may already be happening to some extent even in the ordinary metals and alloys we use in our daily lives — at least for subsurface cracks that are not exposed to oxygen, and possibly even for surface cracks,” Boyce said. “To take full advantage, however, we can begin to think about material sections and microstructural design.”

 

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The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

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NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.

Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.

She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.

Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.

“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.

It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.

Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.

Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.

Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.

“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.

He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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B.C. sets up a panel on bear deaths, will review conservation officer training

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VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.

Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”

Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.

“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.

B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.

Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.

Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.

Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.

“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”

Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”

“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.

Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.

“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.

This report by The Canadian Press was first published Sept. 9, 2024.

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