Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: chemistry – Page 301

Tiny particles produce huge photon avalanches

Researchers in the US, Poland and Korea have observed photon avalanching – a chain-reaction-like process in which the absorption of a single photon triggers the emission of many – in tiny crystals just 25–30 nm in diameter. This highly nonlinear phenomenon had previously only been seen in bulk materials, and team leader James Schuck says that replicating it in nanoparticles could lead to “revolutionary new applications” in imaging, sensing and light detection (Nature 589 230).

Photon avalanching involves a process known as upconversion, whereby the energy of the emitted photons is higher than the energy of the photons that triggered the avalanche. Materials based on lanthanides (chemical elements with atomic numbers between 57 and 71) can support this process in part because their internal atomic structure enables them to store energy for long periods of time. Even so, achieving photon avalanching in lanthanide systems is difficult because high concentrations of lanthanide ions are needed to keep the avalanche going, and the relatively large volume of material required has previously restricted applications.

In the latest work, Schuck and colleagues at Columbia University, together with collaborators at Lawrence Berkeley National Laboratory, the Polish Academy of Sciences and Sungkyunkwan University, observed photon avalanching in lanthanide nanocrystals after exciting them with a laser at near-infrared wavelengths of either 1,064 or 1450 nm. The crystals are based on sodium yttrium fluoride in which 8% of the yttrium ions have been replaced with thulium. This doping fraction is much higher than the 0.2–1% typically found in previous work on photon avalanching.

Biometric authentication using breath

An artificial nose, which is combined with machine learning and built with a 16-channel sensor array was found to be able to authenticate up to 20 individuals with an average accuracy of more than 97%.

“These techniques rely on the physical uniqueness of each individual, but they are not foolproof. Physical characteristics can be copied, or even compromised by injury,” explains Chaiyanut Jirayupat, first author of the study. “Recently, human scent has been emerging as a new class of biometric authentication, essentially using your unique chemical composition to confirm who you are.”

The team turned to see if human breath could be used after finding that the skin does not produce a high enough concentration of volatile compounds for machines to detect.

Supercomputer Helps Understand the Physics of Thought

Decades of research has led to a thorough understanding of the main protein players and the broad strokes of membrane fusion for synaptic transmission. Bernard Katz was awarded the 1970 Nobel Prize in Medicine in part for demonstrating that chemical synaptic transmission consists of a neurotransmitter-filled synaptic vesicle fusing with the plasma membrane at nerve endings and releasing its content into the opposing postsynaptic cell. And Rizo-Rey’s longtime collaborator, Thomas Südhof, won the Nobel Prize in Medicine in 2013 for his studies of the machinery that mediates neurotransmitter release (many with Rizo-Rey as a co-author).

But Rizo-Rey says his goal is to understand the specific physics of how the activation process of thought occurs in much more detail. “If I can understand that, winning the Nobel Prize would just be a small reward,” he said.

Recently, using the Frontera supercomputer at the Texas Advanced Computing Center (TACC), one of the most powerful systems in the world, Rizo-Rey has been exploring this process, creating a multi-million atom model of the proteins, the membranes, and their environment, and setting them in motion virtually to see what happens, a process known as molecular dynamics.

The Rise of Supersoldiers — How AI Changes Everything

Artificial Intelligence is touching almost every aspect of our lives. It’s reasonable to expect AI influence will only increase in the future. One of many fields heavily influenced by AI is the military. Particularly in the development of Supersoldiers. The notion of super-soldiers enhanced with biotechnology and cybernetics was once only possible in the realm of science fiction. But it may not be too long before these concepts become a reality.

A new worldwide arms race is pitting countries against each other to be the first to successfully create real genetically modified super soldiers by using tools such as CRISPR. Understandably many of these human enhancement technologies raise health and safety questions and it is more likely these enhancements will first gain traction in countries that do not place as much weight on ethical concerns.

According to US Intelligence, China has conducted “human testing” on members of the People’s Liberation Army in hope of developing soldiers with “biologically enhanced capabilities.

This has made the U.S. military’s top intelligence agencies increasingly worried but the Pentagon has significantly invested in its own research in AI and in the extension of the human senses beyond their current physical limitations, to provide soldiers with superhuman abilities.

The basics of brain-machine interfaces with AI are being developed for the military, and if the results are as successful as scientists hope they will be, soldiers could one day be enhanced with cybernetics, effectively becoming trans-human soldiers.

The US Military is also examining newly scientific tools, like genetic engineering, brain chemistry, and shrinking robotics, for even more dramatic enhancements. But most of this advanced technology remains classified.

Continue reading “The Rise of Supersoldiers — How AI Changes Everything” | >

As chemical fertilizer shortages persist, peecycling — the process of recycling human urine — could increase the yield of nutrient-rich crops

The need to find alternative sources for fertilizer have become urgent as chemical fertilizer shortages from the Ukrainian war threaten countries globally.

A Chinese military analyst suggested countermeasures for the Starlink satellite system developed by Musk’s SpaceX – including ways to hack or destroy the service.

Biochemistry Researchers Repair and Regenerate Heart Muscle Cells

Researchers at the University of Houston are reporting a first-of-its-kind technology that not only repairs heart muscle cells in mice but also regenerates them following a heart attack, or myocardial infarction as its medically known.

Published in The Journal of Cardiovascular Aging 0, the groundbreaking finding has the potential to become a powerful clinical strategy for treating heart disease in humans, according to Robert Schwartz, Hugh Roy and Lillie Cranz Cullen Distinguished Professor of biology and biochemistry at the UH College of Natural Sciences and Mathematics.

The new technology developed by the team of researchers uses synthetic messenger ribonucleic acid (mRNA) to deliver mutated transcription factors — proteins that control the conversion of DNA into RNA — to mouse hearts.

Process to customize molecules does double duty

Inspired by your liver and activated by light, a chemical process developed in labs at Rice University and in China shows promise for drug design and the development of unique materials.

Researchers led by Rice chemist Julian West and Xi-Sheng Wang at the University of Science and Technology of China, Hefei, are reporting their successful catalytic process to simultaneously add two distinct functional groups to single alkenes, drawn from petrochemicals that contain at least one carbon-carbon double bond combined with .

Better yet, they say, is that these alkenes are “unactivated”—that is, they lack reactive atoms near the double bond—and until now, have proven challenging to enhance.

Using microbrewery waste to synthesize carbon quantum dots

For a few years now, spent grain, the cereal residue from breweries, has been reused in animal feed. This material could also be used in nanotechnology. Professor Federico Rosei’s team at the Institut national de la recherche scientifique (INRS) has shown that microbrewery waste can be used as a carbon source to synthesize quantum dots. The work, done in collaboration with Claudiane Ouellet-Plamondon of the École de technologie supérieure (ÉTS), was published in the Royal Society of Chemistry’s journal RSC Advances.

Often considered “artificial atoms,” are used in the transmission of light. With a range of interesting physicochemical properties, this type of nanotechnology has been successfully used as a sensor in biomedicine or as LEDs in next generation displays. But there is a drawback. Current quantum dots are produced with heavy and toxic metals like cadmium. Carbon is an interesting alternative, both for its biocompatibility and its accessibility.

Organ storage a step closer with cryopreservation discovery

Australian scientists have taken the first step towards improved storage of human cells, which may lead to the safe storage of organs such as hearts and lungs.

The team’s discovery of new cryoprotective agents opens the door to many more being developed that could one day help to eliminate the need for organ transplant waiting lists. Their results are published in the Journal of Materials Chemistry B.

Cryopreservation is a process of cooling biological specimens down to very low temperatures so they can be stored for a long time. Storing cells through cryopreservation has had big benefits for the world—including boosting supplies at blood banks and assisting reproduction—but it is currently impossible to store organs and simple tissues.

/* */