Tag Archives: nuggets

Researchers develop chicken nuggets cultured in the biggest laboratory ever, complete with synthetic veins

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A significant breakthrough has been made in the field of cultured meat, with scientists successfully growing nugget-sized chicken using a new method that enables the delivery of nutrients and oxygen to artificial tissues.

In the past, lab-produced tissues were limited to cell spheres less than a millimeter thick, making it challenging to replicate the texture of real muscle. However, a team of Japanese researchers has now managed to grow a chicken measuring 2.7 inches wide and 0.7 inches thick using a new lab tool, marking a major step forward in this technology. Biotechnology trends.

The development of bioreactors that mimic the circulation system has played a crucial role in this breakthrough, with 50 hollow fibers distributing nutrients and oxygen into the meat to allow cells to grow in a specific direction.

This lab-grown chicken, although not made from food-grade ingredients and not yet tasted by scientists, showcases the potential of this technology for various applications beyond food production.

As the technology advances, challenges such as replicating the texture and flavor of traditional meat and improving oxygen delivery for larger pieces still need to be addressed. Automation of the process and the use of food-grade ingredients are crucial steps towards making lab-grown meat commercially viable.

Consumer attitudes towards cultured meat vary, with some expressing concerns about its safety and perceived unnaturalness. Despite these challenges, cultured meat is already available in some markets and holds promise for a more sustainable future.

The future of cultured meat holds potential for significant advancements in food production, regenerative medicine, drug testing, and biohybrid robotics, paving the way for a more sustainable and innovative future.

Source: www.nbcnews.com

Study finds earthquake-triggered piezoelectric effect is essential in the creation of sizable gold nuggets

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Gold nuggets reside primarily in quartz veins, and the current paradigm holds that gold precipitates from hydrothermal and carbon dioxide-rich fluids due to changes in temperature, pressure, and/or fluid chemistry. However, the widespread occurrence of large gold nuggets is inconsistent with the dilute nature of these fluids and the chemical inertness of quartz. Quartz is the only abundant piezoelectric mineral on Earth, and the cyclical nature of the seismic activity that drives the formation of gold deposits means that quartz crystals within veins are stressed thousands of times. New research by scientists from Monash University, CSIRO Mineral Resources and the Australian Neutron Scattering Centre suggests that stress on quartz crystals may generate enough voltage to not only electrochemically precipitate gold from solution, but also accumulate gold nanoparticles.

Energy dispersive spectroscopy map of the sample studied by Voysey othersImage courtesy of Chris Voisey.

“Prized for their rarity and beauty, gold nuggets have been at the heart of gold rushes for centuries,” says Monash University geologist Chris Voisey.

“The standard explanation is that gold precipitates from hot, water-rich fluids that flow through cracks in the Earth's crust.”

“As these fluids cool and undergo chemical changes, the gold separates and becomes trapped in the quartz veins.”

“Although this theory is widely accepted, it does not fully explain the formation of large gold nuggets, especially considering the extremely low concentrations of gold in these liquids.”

Dr. Voysey and his colleagues tested a new concept called piezoelectricity.

Quartz, the mineral that typically contains these gold deposits, has a unique property called piezoelectricity, which means it generates an electric charge when subjected to pressure.

This phenomenon is already well known in everyday items such as quartz watches and barbecue lighters, where small mechanical forces generate large voltages.

What if earthquake stresses caused something similar to happen within the Earth?

To test this hypothesis, the researchers conducted experiments designed to replicate conditions that quartz might experience during an earthquake.

They submerged the crystals in a gold-rich liquid and used a motor to apply pressure to it, replicating the shaking of an earthquake.

After the experiment, the quartz samples were examined under a microscope to see if any gold had been deposited.

“The results were surprising,” said Professor Andy Tomkins, from Monash University.

“The stressed quartz not only electrochemically deposited gold on its surface, but also formed and accumulated gold nanoparticles.”

“Surprisingly, the gold tended to deposit on top of existing gold grains rather than forming new gold grains.”

“This is because quartz is an electrical insulator, while gold is a conductor.”

“Once the gold is deposited, it becomes a focus for further growth, effectively attaching even more gold to the gold particle.”

“Our findings provide a plausible explanation for why large gold nuggets form in quartz veins,” Dr Voysey said.

When the quartz is repeatedly compressed by an earthquake, a piezoelectric voltage is generated, causing dissolved gold to be reduced and precipitated from the surrounding liquid.

Over time, this process can accumulate large amounts of gold, eventually producing giant gold nuggets that fascinate treasure hunters and geologists.

“Essentially, the quartz acts like a natural battery, with the gold as its electrodes, slowly accumulating gold with each earthquake,” Dr Voysey said.

“This process may explain why large gold nuggets are frequently associated with quartz veins that form in earthquake-related deposits.”

“This new understanding of the formation of gold nuggets not only solves a long-standing geological mystery, but also highlights the interrelationships between Earth's physical and chemical processes.”

a paper A paper describing the results was published today in the journal Nature Chemistry.

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CR Voysey othersThe formation of gold nuggets due to earthquake-induced piezoelectric effect in quartz. National GeographyPublished on September 2, 2024, doi: 10.1038/s41561-024-01514-1

Source: www.sci.news

Earthquakes as a possible explanation for the formation of giant gold nuggets in quartz rock

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A replica of the “Welcome Stranger,” a 100 kg gold nugget discovered in Australia in 1869.

Ian Dagnall/Alamy

Earthquakes can create electric fields that attract gold dissolved in liquids pushed up from deep within the earth, causing gold nuggets to form in the quartz.

Giant gold nuggets are often associated with quartz, a ubiquitous but chemically inert mineral. The world's largest gold nuggets can weigh nearly 100 kilograms, but until now no one has been able to explain how such masses of precious metal formed.

“The mystery was how someone could create such a large nugget of gold in one place without any obvious chemical or physical traps,” he said. Chris Voysey At Monash University, Melbourne.

Voysey and his colleagues discovered a possible mechanism: applying pressure to the quartz creates a voltage that attracts gold dissolved in water.

The secret lies in the structure of quartz, Voysey explains. Quartz is the only abundant mineral whose crystals have no center of symmetry. This means that when these crystals are strained or stressed by seismic activity, their internal electromagnetic makeup changes, generating electricity. Electricity generated in response to mechanical stress is known as piezoelectricity.

Gold-bearing hydrothermal fluids rise up through fissures during seismic activity from the mid-to-lower crust, 15-20 km below the surface, but gold is so dilute that it would take the equivalent of five Olympic swimming pools of hydrothermal fluid to produce 10 kg of gold.

Voysey and his colleagues hypothesized that the piezoelectric properties of quartz would cause the gold to concentrate in nodules within the veins during repeated earthquakes. To test this idea, the team performed experiments in which they placed quartz crystals in a gold-containing solution and applied moderate pressure from an actuator.

Quartz samples that were not subjected to pressure did not attract gold, but samples subjected to force generated a voltage and attracted the metal. Some of the samples were coated with iridium to accentuate the piezoelectric response of the quartz and artificially mimic the expansion of seismic activity. In these samples, large gold flakes grew, over 6000 nanometers, compared to 200-300 nanometers in uncoated quartz.

Once gold starts to deposit on the quartz, it quickly attracts other gold, Voysey says. “Gold is a conductor, so gold in solution tends to deposit on top of existing gold,” he says. “It becomes like a lightning rod that attracts more gold.”

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Source: www.newscientist.com