Life (as we know it) is based on carbon. Despite its ubiquity, this important element still holds plenty of secrets, on earth and in the heavens above us. For example, astrophysicists like Columbia’s Daniel Wolf Savin who study interstellar clouds want to understand how the chemicals, including carbon, swirling within these nebulous aggregations of gas and dust form the stars and planets that dot our universe and give rise to organic life.
Next big thing Haifei Zhan and colleagues reckon that carbon nanothreads have a future in energy storage. (Courtesy: Queensland University of Technology) Computational and theoretical studies of diamond-like carbon nanothreads suggest that…
Computational and theoretical studies of diamond-like carbon nanothreads suggest that they could provide an alternative to batteries by storing energy in a strained mechanical system. The team behind the research says that nanothread devices could power electronics and help with the shift towards renewable sources of energy.
The traditional go-to device for energy storage is the electrochemical battery, which predates even the widespread use of electricity. Despite centuries of technological progress and near ubiquitous use, batteries remain prone to the same inefficiencies and hazards as any device based on chemical reactions – sluggish reactions in the cold, the danger of explosion in the heat and the risk of toxic chemical leakages.
Another way of storing energy is to strain a material that then releases energy as it returns to its unstrained state. The strain could be linear like stretching and then launching a rubber band from your finger; or twisted, like a wind-up clock or toy. More than a decade ago, theoretical work done by researchers at the Massachusetts Institute of Technology suggested that strained chords made from carbon nanotubes could achieve impressive energy-storage densities, on account of the material’s unique mechanical properties.
An electrochemically powered artificial muscle made from twisted carbon nanotubes contracts more when driven faster thanks to a novel conductive polymer coating. Developed by Ray Baughman of the University of Texas at Dallas in the US and an international team, the device overcomes some of the limitations of previous artificial muscles, and could have applications in robotics, smart textiles and heart pumps.
Carbon nanotubes (CNTs) are rolled-up sheets of carbon with walls as thin as a single atom. When twisted together to form a yarn and placed in an electrolyte bath, CNTs expand and contract in response to electrochemical inputs, much like a natural muscle. In a typical set-up, a potential difference between the yarn and an electrode drives ions from the electrolyte into the yarn, causing the muscle to actuate.
While such CNT muscles are highly energy efficient and extremely strong – they can lift loads up to 100,000 times their own weight – they do have limitations. The main one is that they are bipolar, meaning that the direction of their movement switches whenever the potential drops to zero. This reduces the overall stroke of the actuator. Another drawback is that the muscle’s capacitance decreases when the potential is changed quickly, which also causes the stroke to decrease.
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.
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.
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.
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.
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.
Posted in chemistry
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.
