From Cauchy to Dirac — A Century-Long Journey. “A Brief History of Dirac Delta Function” is published by Areeba Merriam in Cantor’s Paradise.
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“With this material, the dawn of ambient superconductivity and applied technologies has arrived,” said the press release, which was published today by a team led by Ranga Dias, an assistant professor of mechanical engineering and physics.
Lipid nanoparticles (LNPs) transport small molecules into the body. The most well-known LNP cargo is mRNA, the key constituent of some of the early vaccines against COVID-19. But that is just one application: LNPs can carry many different types of payload, and have applications beyond vaccines.
Barbara Mui has been working on LNPs (and their predecessors, liposomes) since she was a PhD student in Pieter Cullis’s group in the 1990s. “In those days, LNPs encapsulated anti-cancer drugs,” says Mui, who is currently a senior scientist at Acuitas, the company that developed the LNPs used in the Pfizer-BioNTech mRNA vaccine against SARS-CoV-2. She says it soon became clear that LNPs worked even better as carriers of polynucleotides. “The first one that worked really well was encapsulating small RNAs,” Mui recalls.
But it was mRNA where LNPs proved most effective, primarily because LNPs are comprised of positively charged lipid nanoparticles that encapsulate negatively charged mRNA. Once in the body, LNPs enter cells via endocytosis into endosomes and are released into the cytoplasm. “Without the specially designed chemistry, the LNP and mRNA would be degraded in the endosome,” says Kathryn Whitehead, professor in the departments of chemical engineering and biomedical engineering at Carnegie Mellon University.
Recycling spent lithium-ion batteries plays a significant role in alleviating the shorting of raw materials and environmental problems. However, recycled materials are deemed inferior to commercial materials, preventing the industry from adopting recycled materials in new batteries.
Now, researchers at Worcester Polytechnic Institute (WPI) in Massachusetts have demonstrated that the recycled materials from used lithium-ion batteries can outperform new commercial materials, making the recycled materials a potentially green and profitable resource for battery producers. Led by Yan Wang, professor in the Department of Mechanical and Materials Engineering, the team of researchers used physical tests, imaging, and computer simulations to compare new cathode materials recovered from old electric vehicle batteries through a recycling process, which is being commercialized by Battery Resourcers Inc. of Worcester.
The technology involved shredding batteries and removing the steel cases, aluminum and copper wires, plastics, and pouch materials for recycling. Researchers then dissolved the metals from those battery bits in an acidic solution. They by tweaking the solution’s pH, the team removed impurities such as iron and copper and recovered over 90% of three key metals – nickel, manganese, and cobalt. The recovered metals formed the basis for the team’s cathode material.
Imagine a world with precision medicine, where a swarm of microrobots delivers a payload of medicine directly to ailing cells. Or one where aerial or marine drones can collectively survey an area while exchanging minimal information about their location.
One early step towards realizing such technologies is being able to simultaneously simulate swarming behaviors and synchronized timing—behaviors found in slime molds, sperm and fireflies, for example.
In 2014, Cornell researchers first introduced a simple model of swarmalators—short for “swarming oscillator”—where particles self-organize to synchronize in both time and space. In the study, “Diverse Behaviors in Non-uniform Chiral and Non-chiral Swarmalators,” which published Feb. 20 in the journal Nature Communications, they expanded this model to make it more useful for engineering microrobots; to better understand existing, observed biological behaviors; and for theoreticians to experiment in this field.
George Church is a geneticist known for his pioneering work in developing new technologies for genome sequencing, editing, and synthesis. He has also been involved in research on genome engineering and gene therapy.
Links.
https://wyss.harvard.edu/team/core-faculty/george-church/
https://arep.med.harvard.edu/
Tiny insects known as sharpshooters excrete by catapulting urine drops at incredible accelerations. Their excretion is the first example of superpropulsion discovered in a biological system.
Saad Bhamla was in his backyard when he noticed something he had never seen before: an insect urinating. Although nearly impossible to see, the insect formed an almost perfectly round droplet on its tail and then launched it away so quickly that it seemed to disappear. The tiny insect relieved itself repeatedly for hours.
Technological and engineering advances let researchers delve deeper into cell function and behavior in physiological and pathological settings.
Saad Bhamla was in his backyard when he noticed something he had never seen before: an insect urinating. Although nearly impossible to see, the insect formed an almost perfectly round droplet on its tail and then launched it away so quickly that it seemed to disappear. The tiny insect relieved itself repeatedly for hours.
It’s generally taken for granted that what goes in must come out, so when it comes to fluid dynamics in animals, the research is largely focused on feeding rather than excretion. But Bhamla, an assistant professor in the School of Chemical and Biomolecular Engineering at the Georgia Institute of Technology, had a hunch that what he saw wasn’t trivial.
“Little is known about the fluid dynamics of excretion, despite its impact on the morphology, energetics, and behavior of animals,” Bhamla said. “We wanted to see if this tiny insect had come up with any clever engineering or physics innovations in order to pee this way.”
Water is a vital resource, and clean water is a necessity. Texas A&M University researchers have developed a new technique to monitor one of the key processes of purifying water in real time.
Raw water contains microscopic pathogens that are too small to remove during water and wastewater treatment easily. Chemicals are added to form large clumps called flocs, which are easily filtered out. Flocculation is the process used in water treatment to remove suspended particles from the water.
“Coagulant chemicals need to be added to purify drinking water and remove turbidity (cloudiness) and microbes that are too small to be visible to the naked eye,” said Dr. Kuang-An Chang, professor in the Zachry Department of Civil and Environmental Engineering at Texas A&M.
