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Researchers Unlock the Secret to Stronger, Longer-Lasting Glass
Posted by Okachinepa on 12/15/2024 @ 
SynEVOL Source
Shattered Wine Glass
Courtesy of SynEvol
Credit: Tohuko University


Everybody has experienced the terrifying moment when a glass slips out of their hands and breaks into fragments as it hits the floor. However, what if this frequent accident were to disappear?

Researchers at Tohoku University have now made a novel discovery that may lead to the development of extremely resilient materials by providing insights into how glass resists breaking. The innovation has broad ramifications for the glass industry.

As an associate professor at Tohoku University's Graduate School of Science, Makina Saito notes that "glass, although strong, is prone to breaking when stress exceeds its tolerance, but interestingly, the movement of atoms and molecules within glass can relax internal stress, making the material more resistant to fractures." "Even though we are aware that certain atoms "jump" into adjacent empty spaces, it has long been unclear how this process reduces stress."

A hitherto unidentified process of stress relaxation in ionic glass, a model system of glass, was discovered by Saito and his colleagues, who included scientists from Kyoto University, Shimane University, the National Institute for Materials Science, and the Japan Synchrotron Radiation Research Institute.


Schematic of the Model Ionic Glass Structure Experimental Apparatus and Specimen
Courtesy of SynEvol
Credit: Tohuko University

They observed atomic vibrations in glass on a nanosecond-to-microsecond timescale using computer modeling and cutting-edge synchrotron radiation experiments.

The team found that surrounding groupings of atoms gradually move together to fill the void when some of the atoms in the glass "jump" into adjacent empty regions. By reducing internal stress through the interaction of atomic jumps and collective motion, the glass is shielded from shattering when subjected to external force.

According to Saito, "our findings have broad ramifications for sectors like consumer electronics, construction, and automotive manufacturing, where break-resistant glass is crucial."

The study team intends to investigate if comparable atomic mechanisms function in other kinds of glass in the future. Their ultimate objective is to create global standards for creating glass with exceptional impact resistance, which has the potential to transform applications that call for long-lasting materials.






New 3D X-Ray Technology Revolutionizes Material Science
Posted by Okachinepa on 12/15/2024 @ 
SynEVOL Source
Mapping the Nanoscale Architecture of Functional Materials
Courtesy of SynEvol
Credit: Paul Scherrer Institute 


Numerous coherent domains or grains can be seen while examining the micro- or nanostructure of functional materials, whether they are man-made or natural. These grains are discrete areas with recurring, ordered patterns of atoms and molecules.

The characteristics of the material are directly related to how these grains are arranged. Their distribution, size, and orientation can determine whether a brick is stable or crumbles. They establish a metal's ductility, a semiconductor's electron transfer efficiency, and the heat conductivity of ceramics. Biological materials also depend heavily on this structural arrangement; collagen fibers, for instance, are composed of interwoven fibrils, and the alignment of these fibrils influences the mechanical strength of connective tissues.

These domains are frequently quite small, measuring only tens of nanometers. And what determines their properties is how they are arranged in three dimensions across large quantities. However, methods for examining how materials are organized at the nanoscale have mostly been limited to two dimensions or are destructive in nature.

Researchers from the Paul Scherrer Institute PSI, ETH Zurich, the University of Oxford, and the Max Plank Institute for Chemical Physics of Solids have now developed an imaging method to access this data in three dimensions using X-rays produced by the Swiss Light Source SLS.

X-ray linear dichroic orientation tomography, or XL-DOT for short, is the name of their method. XL-DOT investigates how materials absorb X-rays differently based on the orientation of their internal structural domains using polarized X-rays from the Swiss Light Source SLS. The method produces a three-dimensional map that shows the interior structure of the material by altering the X-rays' polarization while rotating the sample to take pictures from various perspectives.

The group utilized their technique on a piece of vanadium pentoxide catalyst, which is used to produce sulfuric acid, and has a diameter of around one micron. Here, scientists were able to detect minute characteristics in the structure of the catalyst, such as crystalline grains, grain boundaries, and shifts in the orientation of the crystal. Additionally, they discovered topological flaws in the catalyst. For example, Understanding this structure is essential for maximizing performance because these characteristics have a direct impact on the stability and activity of catalysts.

The technique achieves excellent spatial resolution, which is significant. The technique can discern structures as small as tens of nanometers, which corresponds to the sizes of features like crystalline grains, because X-rays have a short wavelength.

Anisotropies in materials have long been measured using linear dichroism, but this is the first time it has been applied to three dimensions. According to Valerio Scagnoli, Senior Scientist at the Mesoscopic Systems, a collaborative project between PSI and ETH Zurich, "We not only look inside, but with nanoscale resolution." "This means that we can attain this in small but representative samples, several micrometers in size, and we now have access to information that was not previously visible."

Even if the researchers came up with the concept for XL-DOT in 2019, it would require five more years to implement. The extraction of the three-dimensional map of crystal orientations from terabytes of raw data was a significant challenge in addition to the intricate experimental needs. Andreas Apseros, the study's first author, solved this mathematical conundrum by creating a specialized reconstruction method while pursuing his doctoral studies at PSI with funding from the Swiss National Science Foundation (SNSF).

The long-term dedication to gaining proficiency with coherent X-rays at PSI, which resulted in unparalleled control and instrument stability at the coherent Small Angle X-ray Scattering (cSAXS) beamline—essential for the delicate measurements—is credited by the researchers with helping them develop XL-DOT.

Following the SLS 2.0 upgrade, this field is expected to advance significantly: According to Apseros, "coherence is where we're really set to gain with the upgrade." "Since we're dealing with very weak signals, more coherent photons will increase the signal and allow us to either reach more challenging materials or achieve higher spatial resolution."

The researchers anticipate operando studies of systems like batteries and catalysts because of the non-destructive nature of XL-DOT. Johannes Ihli, the study's lead and a former employee of cSAXS who is now at the University of Oxford, says, "This is a reasonable next step because catalyst bodies and cathode particles in batteries are typically between ten and fifty micrometers in size."

However, the researchers stress that the novel method is not limited to catalysts. It works well with many kinds of materials that have organized microstructures, including innovative materials for energy storage or information technology as well as biological tissues.

Investigating the three-dimensional magnetic organization of materials is, in fact, the scientific impetus for the study team. The orientation of magnetic moments in antiferromagnetic materials serves as one illustration. In this case, when one moves from atom to atom, the magnetic moments align in opposite directions. These materials have local order in their magnetic structure, which is desirable for technological applications like quicker and more effective data processing, but they do not retain any net magnetism when measured from a distance. Claire Donnelly, group head at the Max Planck Institute for Chemical Physics of Solids in Dresden, states, "Our method is one of the only ways to probe this orientation." Since completing her doctoral study with the Mesoscopic Systems group, she has maintained a close working relationship with the PSI team.

In contrast to XL-DOT, which employs linearly polarized X-rays, Donnelly and the same team at PSI published a method for doing magnetic tomography using circularly polarized X-rays in Nature during this PhD dissertation. Since then, synchrotrons all over the world have adopted this.

The team hopes that XL-DOT will become a common technique at synchrotrons, much like its circularly polarized sister, now that the foundation has been set. The influence of this most recent technique may be anticipated to be even bigger given the far broader range of samples that XL-DOT is relevant to and the significance of structural ordering to material performance. Other beamlines can use the method now that we've solved a lot of the problems. And We can assist them in doing so," Donnelly continues.




AI Finds New Methods of Microscopy in Record Time
Posted by Okachinepa on 12/15/2024 @ 
SynEVOL Source
XLuminA Automated Optical Discovery Process
Courtesy of SynEvol
Credit:Long Huy Dao and Phillip Denghel



New super-resolution microscopy methods are frequently the result of years of laborious human effort. Determining the best location for mirrors, lenses, and other components is one of the many optical setups that can be used in a microscope.

XLuminA is an artificial intelligence (AI) framework created by researchers at the Max Planck Institute for the Science of Light (MPL) to address this. This system does computations 10,000 times faster than conventional techniques while independently exploring and optimizing experimental designs in microscopy. Nature Communications recently published the group's ground-breaking research.

A fundamental component of the biological sciences, optical microscopy allows scientists to examine the tiniest cellular components. By pushing past the standard diffraction limit of light, which is around 250 nm, advances in super-resolution (SR) techniques have enabled researchers to view cellular features that were previously unresolvable. Traditionally, developing new microscopy techniques has relied on human expertise, intuition, and creativity—a daunting challenge given the vast number of possible optical configurations.

For instance, an optical configuration consisting of only 10 parts chosen from 5 different components—such as beam splitters, mirrors, or lenses—can produce more than 100 million distinct configurations. Exploration by humans becomes more challenging due to the design space's extreme complexity, which implies that many potential solutions may still be unknown. This is where AI-based approaches provide a significant benefit, allowing for the quick and objective investigation of various options.

We can see both the big and small scales of the universe through experiments. It's debatable if human researchers have already found every unique configuration given the astronomically high number of viable testing setups. According to Mario Krenn, who leads MPL's Artificial Scientist Lab, "this is exactly where artificial intelligence can help."

The leader of MPL's Physical Glycoscience research group and domain expert in super-resolution microscopy, Leonhard Möckl, teamed up with researchers from the Artificial Scientist Lab to tackle this problem. They collaborated to create XLuminA, a productive open-source framework whose ultimate objective is to uncover novel optical design concepts.

With an emphasis on SR microscopy, the researchers make use of its possibilities. XLuminA functions as an AI-powered optics simulator that is capable of automatically exploring any potential optical configuration. The efficiency of XLuminA is what makes it unique; it uses cutting-edge computational methods to assess possible designs 10,000 times quicker than conventional computational procedures.

"XLuminA is the first step toward combining super-resolution microscopy with AI-assisted discovery." Over the past few decades, super-resolution microscopy has made it possible to gain ground-breaking insights into basic cell biology processes. With XLuminA, I'm confident that this success story will continue, bringing us new designs with previously unheard-of capabilities," says Leonhard Möckl, head of MPL's Physical Glycoscience group.



Carla Rodriguez Crop
Courtesy of SynEvol
Credit:Long Huy Dao and Phillip Denghel

Together with the other team members, Carla Rodríguez, the work's first author, confirmed their methodology by showing that XLuminA could independently relearn three fundamental microscopy techniques. The framework successfully rediscovered a method utilized for image magnification, starting with basic optical configurations.

After overcoming more difficult obstacles, the scientists were able to rediscover the Nobel Prize-winning STED (stimulated emission depletion) microscopy and an optical vortex technique for SR.

Lastly, the scientists showed that XLuminA could make real discoveries. Given the available optical elements, the researchers requested that the framework determine the optimal SR design. The framework separately figured out how to combine the fundamental physical concepts of the two SR methods listed above (optical vortex method and STED microscopy) into a single, unpublished experimental design. This design's performance surpasses that of each separate SR approach.

"I knew we had successfully made an intriguing notion a reality when I saw the first optical designs that XLuminA had found. XLuminA achieves previously unheard-of speed in automated optical design, paving the way for the exploration of whole new microscopy frontiers. Considering how XLuminA could contribute to expanding our knowledge of the globe, I am immensely happy of the work we have done. It's incredibly thrilling to think about the future of automated scientific discovery in optics! Carla Rodríguez, the principal creator of XLuminA and the study's primary author, explains.





Through the Use of Advanced Metamaterials, MIT Unlocks Ultrasound Control
Posted by Okachinepa on 12/15/2024 @ 
SynEVOL Source
Controlling Ultrasound Wave Propagation in Microscopic Acoustic Metamaterials
Courtesy of SynEvol
Credit: MIT Researchers


Acoustic metamaterials are materials that have been particularly created to regulate the movement of elastic waves or sound waves. Although these materials have been studied theoretically and through computer models, only large-scale structures and low-frequency applications have so far been able to produce physical copies.

Carlos Portela, the Robert N. Noyce Career Development Chair and assistant professor of mechanical engineering at MIT, says that metamaterials are excellent candidates for use in extreme-condition engineering applications because of their multifunctionality, which includes being both strong and lightweight while also having adjustable acoustic properties. However, the development of new materials with ultrasonic-wave control capabilities has been hampered by difficulties in the miniaturization and high-frequency characterization of acoustic metamaterials.

Recently, Portela, Washington DeLima from the U.S. Department of Energy's Kansas City National Security Campus, and Rachel Sun, Jet Lem, and Yun Kai from MIT's Department of Mechanical Engineering created a new design framework for managing ultrasonic waves in microscopic acoustic metamaterials. Their research was published in the journal Science Advances under the title "Tailored Ultrasound Propagation in Microscale Metamaterials via Inertia Design."

"Our research suggests a design framework that adjusts the way ultrasonic waves pass through three-dimensional microscale metamaterials by carefully placing microscale spheres," adds Portela. In particular, we look into how the insertion of tiny spherical masses into a metamaterial lattice alters the speed at which ultrasonic waves move through it, ultimately resulting in wave guiding or focusing responses.


Carlos Portela and Rachel Sun
Courtesy of SynEvol
Credit: MIT Researchers

Tunable elastic-wave velocities within microscale materials are experimentally demonstrated by the researchers using high-throughput laser-ultrasonics characterisation that is non-destructive. They demonstrate an acoustic demultiplexer, a device that divides a single acoustic signal into multiple output signals, and use the different wave velocities to geographically and temporally modify wave propagation in microscale materials. The work opens the door for microscale components and devices that may be helpful for ultrasound imaging or ultrasound-based information transfer.

"This design framework enables easy design and fabrication of microscale acoustic metamaterials and devices by expanding the tunable dynamic property space of metamaterials through simple geometrical changes," adds Portela.

The study also highlights the fundamental mechanics of ultrasound wave propagation in metamaterials, tuning dynamic properties via straightforward geometric changes and characterizing these changes as a function of changes in mass and stiffness. Additionally, it advances experimental capabilities, including fabrication and characterization of microscale acoustic metamaterials toward application in medical ultrasound and mechanical computing applications. More significantly, the framework can be made using methods other than microscale manufacturing, using only one base 3D geometry and one constituent material to get largely adjustable attributes.

This framework's essential connection between geometric aspects and physical material qualities is its attractiveness. According to Sun, the study's first author, "we could create direct analogies for how mass affects quasi-static stiffness and dynamic wave velocity by placing spherical masses on a spring-like lattice
scaffold." "I discovered that whether we vibrated or slowly compressed the materials, we could still obtain hundreds of different designs and corresponding material properties."
Microrobots Reduce Tumors in a New Study
Posted by Okachinepa on 12/12/2024 @ 
SynEVOL Source
Bioresorbable Acoustic Hydrogel Microrobots
Courtesy of SynEvol
Credit: Hong Han


In the future, small robots—not metal humanoids or bio-inspired devices, but tiny, bubble-like spheres—may be responsible for delivering medicinal medications exactly where they are required in the body.

These microrobots must overcome a number of difficult obstacles. They have to be able to withstand tough physical conditions like stomach acid, be controlled remotely to get to certain locations, and only release their medication when they get there. They must then be innocuously dissolved in the body.


Hong Han and Xiaotian Ma
Courtesy of SynEvol
Credit: Lance Hayashida /CALTECH


A group lead by Caltech has created microrobots that satisfy each of these specifications. In lab experiments, the robots were able to administer drugs that caused mice's bladder tumors to shrink. Today, December 11, the study was published in detail in the journal Science Robotics.

Wei Gao, a professor of medical engineering at Caltech, an investigator at the Heritage Medical Research Institute, and a co-corresponding author of the new paper about the bots, which the team refers to as bioresorbable acoustic microrobots (BAM), says, "We have designed a single platform that can address all of these problems."

“Rather than putting a drug into the body and letting it diffuse everywhere, now we can guide our microrobots directly to a tumor site and release the drug in a controlled and efficient way,” Gao says.

Micro- or nano-robots are not a novel idea. Over the last 20 years, people have been creating variations of these. However, thus far, their applications in living systems have been limited because it is extremely challenging to move objects with precision in complex biofluids such as blood, urine, or saliva, Gao says. Additionally, the robots must be biocompatible and bioresorbable—that is, they must not leave any harmful residue in the body.


Flow Patterns Made By an Acoustic Hydrogel Microrobot
Courtesy of SynEvol
Credit: Hong Han


The microrobots created by Caltech are spherical microstructures composed of poly(ethylene glycol) diacrylate, a hydrogel. Materials known as hydrogels begin as liquids or resins and solidify as the network of polymers inside them cross-links, or hardens. Because of their composition and structure, hydrogels can hold a lot of fluid, which makes many of them biocompatible. Additionally, the outer sphere can transport the therapeutic cargo to a specific location inside the body thanks to the additive manufacturing creation technology.

Gao turned to Julia R. Greer of Caltech, the Ruben F. and Donna Mettler Professor of Materials Science, Mechanics and Medical Engineering, the Fletcher Jones Foundation Director of the Kavli Nanoscience Institute, and co-corresponding author of the paper, to create the hydrogel recipe and create the microstructures. Greer’s group has expertise in two-photon polymerization (TPP) lithography, a technique that uses extremely fast pulses of infrared laser light to selectively cross-link photosensitive polymers according to a particular pattern in a very precise manner. The technique allows a structure to be built up layer by layer, in a way reminiscent of 3D printers, but in this case, with much greater precision and form complexity.

Greer's team was able to "write," or print out, microstructures that are around 30 microns in diameter, or the diameter of a human hair.

"It is really difficult to write this specific shape, this sphere," Greer says. "You need to know a few tricks of the trade to keep the spheres from falling apart on their own. We were able to correctly write the biofunctionalization and medically necessary components in a spherical shape with the necessary cavity, in addition to producing the resin with all of these components.

When the microrobots are finished, the medicinal medication and magnetic nanoparticles are integrated into the spheres' exterior structure. The scientists may use an external magnetic field to guide the robots to a certain place thanks to the magnetic nanoparticles. The drug passively diffuses out of the robots as they arrive at their destination and stay there.

To prevent the individual robots from clumping together as they move through the body, Gao and colleagues made the exterior of the microstructure hydrophilic, or attracted to water. However, because the microrobot must capture an air bubble—which is easily dissolved or collapsed—its inner surface cannot be hydrophilic.

The researchers developed a two-step chemical alteration process to create hybrid microrobots that are hydrophilic on the outside and hydrophobic, or water-repellent, on the inside. First, they attached long-chain carbon molecules to the hydrogel, making the entire structure hydrophobic. Then the researchers used a technique called oxygen plasma etching to remove some of those long-chain carbon structures from the interior, leaving the outside hydrophobic and the interior hydrophilic.

“This was one of the key innovations of this project,” says Gao, who is also a Ronald and JoAnne Willens Scholar. “This asymmetric surface modification, where the inside is hydrophobic and the outside is hydrophilic, really allows us to use many robots and still trap bubbles for a prolonged period of time in biofluids, such as serum or urine.

In fact, the researchers demonstrated that, in contrast to the few minutes that would be feasible without this therapy, the bubbles can persist for up to many days.

Additionally, the existence of trapped bubbles is essential for both robot mobility and real-time imaging tracking. For example, to enable propulsion, the team designed the microrobot sphere to have two cylinder-like openings—one at the top and another to one side. The surrounding fluid streams away from the robots through the aperture when the bubbles vibrate in an ultrasonic field, which moves the robots through the fluid. Gao’s team found that the use of two openings gave the robots the ability to move not only in various viscous biofluids, as well as more quickly than is possible with a single opening.

An egg-shaped bubble that is trapped inside each microstructure acts as a great contrast agent for ultrasound imaging, allowing for real-time in vivo monitoring of the bots. With the assistance of ultrasound imaging specialists Mikhail Shapiro, Max Delbruck Professor of Chemical Engineering and Medical Engineering at Caltech and a Howard Hughes Medical Institute Investigator, co-corresponding author Di Wu, research scientist and director of the DeepMIC Center at Caltech, and co-corresponding author Qifa Zhou, professor of ophthalmology and biomedical engineering at USC, the team devised a method to track the microrobots as they travel to their targets.

In the latter phase of research, mice with bladder tumors were used to test the microrobots' ability to transport drugs. Over the course of 21 days, the researchers discovered that four therapeutic deliveries made by the microrobots were more successful in reducing tumor size than a therapeutic that was not administered by robots.

Gao states, "We believe this is a very promising platform for precision surgery and drug delivery." In the future, we might consider utilizing this robot as a platform to administer various medicinal chemicals or payloads for various ailments. We also intend to try this on humans in the future.





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