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Category: engineering – Page 63

Two studies report new methods for using metasurfaces to create and control dark areas called “optical singularities.”

Optical devices and materials allow scientists and engineers to harness light for research and real-world applications, like sensing and microscopy. Federico Capasso’s group at the Harvard John A. Paulson School of Engineering Applied Sciences (SEAS) has dedicated years to inventing more powerful and sophisticated optical methods and tools. Now, his team has developed new techniques to exert control over points of darkness, rather than light, using metasurfaces.

“Dark regions in electromagnetic fields, or optical singularities, have traditionally posed a challenge due to their complex structures and the difficulty in shaping and sculpting them. These singularities, however, carry the potential for groundbreaking applications in fields such as remote sensing and precision measurement,” said Capasso, the Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering at SEAS and senior corresponding author on two new papers describing the work.

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The field of bone implants has taken incredible strides thanks to technological innovations that allow for stronger grafts that are easier to install. Yet even with these advances, there are still risks involved in such procedures. Implants can be loosened following operations, for example, which can lead to costly surgical revisions that lengthen the recovery process for patients.

New research published in Nature Biomedical Engineering from an interdisciplinary team from Northwestern Engineering’s Center for Advanced Regenerative Engineering (CARE) and Center for Physical Genomics and Engineering (CPGE) could reduce the likelihood of these painful, expensive complications.

Working at the convergence of the physical sciences, biology, surgery, and engineering, the investigators introduced the concept of surface topography-induced chromatin engineering. In a collaboration with The University of Chicago’s Russell R. Reid, MD, Ph.D., and Tong-Chuan He, MD, Ph.D., the team explained how and why to use surfaces to change patterns, validating the method in vivo.

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As we age, our bodies change and degenerate over time in a process called senescence. Stem cells, which have the unique ability to change into other cell types, also experience senescence, which presents an issue when trying to maintain cell cultures for therapeutic use. The biomolecules produced by these cell cultures are important for various medicines and treatments, but once the cells enter a senescent state they stop producing them, and worse, they instead produce biomolecules antagonistic to these therapeutics.

While there are methods to remove older cells in a culture, the capture rate is low. Instead of removing older cells, preventing the cells from entering in the first place is a better strategy, according to Ryan Miller, a postdoctoral fellow in the lab of Hyunjoon Kong (M-CELS leader/EIRH/RBTE), a professor of chemical and biomolecular engineering.

“We work with , that are derived from fat tissue, and produce biomolecules that are essential for therapeutics, so we want to keep the cell cultures healthy. In a clinical setting, the ideal way to prevent senescence would be to condition the environment that these stem cells are in, to control the oxidative state,” said Miller. “With , you can pull them the cells out of this senescent state and make them behave like a healthy stem cell.”

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In energy policy debates, nuclear energy and renewable energy technologies are sometimes viewed as competitors.

In reality, they could be better, together.

At the University of Wisconsin-Madison, Ben Lindley, an assistant professor of engineering physics and an expert on nuclear reactors, and Mike Wagner, an assistant professor of mechanical engineering and a solar energy expert, are studying the feasibility and benefits of such a coupling.

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Simple molecular liquids such as water or glycerol are of great importance for technical applications, in biology or even for understanding properties in the liquid state. Researchers at the Max Planck Institut für Struktur und Dynamik der Materie (MPSD) have now succeeded in observing liquid glycerol in a completely unexpected rubbery state.

In their article published in Proceedings of the National Academy of Sciences, the researchers report how they created rapidly expanding on the surface of the liquid in vacuum using a pulsed laser. However, the thin, micrometers-thick liquid envelope of the bubble did not behave like a viscous liquid dissipating deformation energy as expected, but like the elastic envelope of a rubber toy balloon, which can store and release elastic energy.

It is the first time an elasticity dominating the flow behavior in a Newtonian liquid like glycerol has been observed. Its existence is difficult to reconcile with common ideas about the interactions in liquid glycerol and motivates the search for more comprehensive descriptions. Surprisingly, the elasticity persists over such long timescales of several microseconds that it could be important for very rapid engineering applications such as micrometer-confined flows under . Yet, the question remains unsettled whether this behavior is a specific property of liquid glycerol, or rather a phenomenon that occurs in many molecular liquids under similar conditions but has not been observed so far.

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Scientists find a protein common to flies and people is essential for supporting the structure of axons that neurons project to make circuit connections.

In a study conducted by MIT

MIT is an acronym for the Massachusetts Institute of Technology. It is a prestigious private research university in Cambridge, Massachusetts that was founded in 1861. It is organized into five Schools: architecture and planning; engineering; humanities, arts, and social sciences; management; and science. MIT’s impact includes many scientific breakthroughs and technological advances. Their stated goal is to make a better world through education, research, and innovation.

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Significantly improved electric vehicle (EV) batteries could be a step closer thanks to a new study led by University of Oxford researchers, published today in Nature. Using advanced imaging techniques, this revealed mechanisms which cause lithium metal solid-state batteries (Li-SSBs) to fail. If these can be overcome, solid-state batteries using lithium metal anodes could deliver a step-change improvement in EV battery range, safety and performance, and help advance electrically powered aviation.

One of the co-lead authors of the study Dominic Melvin, a PhD student in the University of Oxford’s Department of Materials, said: ‘Progressing solid-state batteries with lithium metal anodes is one of the most important challenges facing the advancement of battery technologies. While lithium-ion batteries of today will continue to improve, research into solid-state batteries has the potential to be high-reward and a gamechanger technology.’

Li-SSBs are distinct from other batteries because they replace the flammable liquid electrolyte in conventional batteries with a solid electrolyte and use lithium metal as the anode (negative electrode). The use of the solid electrolyte improves the safety, and the use of lithium metal means more energy can be stored. A critical challenge with Li-SSBs, however, is that they are prone to short circuit when charging due to the growth of ‘dendrites’: filaments of lithium metal that crack through the ceramic electrolyte. As part of the Faraday Institution’s SOLBAT project, researchers from the University of Oxford’s Departments of Materials, Chemistry and Engineering Science, have led a series of in-depth investigations to understand more about how this short-circuiting happens.

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The first lithography tools were fairly simple, but the technologies that produce today’s chips are among humankind’s most complex inventions.

When we talk about computing these days, we tend to talk about software and the engineers who write it. But we wouldn’t be anywhere without the hardware and the physical sciences that have enabled it to be created—disciplines like optics, materials science, and mechanical engineering. It’s thanks to advances in these areas that we can fabricate the chips on which all the 1

Semiconductor lithography, the manufacturing process responsible for producing computer… More.

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Low-cost, flexible displays that use very little energy could be a step closer, thanks to an innovation from the University of Surrey that solves a problem that has plagued source-gated transistors (SGT). The study has been published by IEEE Transactions on Electron Devices.

Dr. Radu Sporea, project lead from the University of Surrey, said, We used a rapidly emerging semiconductor material called IGZO or indium-gallium-zinc oxide to create the next generation of source-gated transistors. Through nanoscale contact engineering, we obtained transistors that are much more stable with temperature than previous attempts. Device simulations allowed us to understand this effect.

This new design adds to SGTs and retains usual benefits like using low power, producing high signal amplification, and being more reliable under different conditions. While source-gated transistors are not mainstream because of a handful of performance limitations, we are steadily chipping away at their shortcomings.

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