Amazing Science

Cancer cells have evolved mechanisms to escape the body's immune defense. Agents that prevent immune escape are attractive targets for the development of new cancer therapies. A group of scientists led by Herbert Waldmann and Slava Ziegler at the Max Planck Institute of Molecular Physiology in Dortmund has now developed a new cell-based test system to identify immunoregulatory modulators. Screening a library of over 150,000 substances revealed several potent substances with unprecedented structure.

The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole, has revealed today a new view of the massive object at the center of the M87 galaxy: how it looks in polarized light. This is the first time astronomers have been able to measure polarization, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, is able to launch energetic jets from its core.

University of Illinois at Urbana-Champaign Astronomy and Physics Professor Charles Gammie is part of the EHT theory and simulation working group. Gammie is the Willett Professor of Physics and a founding member of the Illinois Center for Advanced Studies of the Universe (ICASU).  Gammie says, “Our research group at Illinois developed numerical procedures that capture the turbulent flow of gas in the strong gravitational pull of the black hole and then simulate the production and propagation of polarized light, taking into account the black hole's gravitational field. “Illinois graduate students George Wong and Ben Prather played a vital role in creating the simulations used to the analyze the new results. They were also part of the paper writing team for the polarization theory paper published today in The Astrophysical Journal.”

The bright jets of energy and matter that emerge from M87’s core and extend at least 5000 light-years from its center are one of the galaxy’s most mysterious and energetic features. Most matter lying close to the edge of a black hole falls in. However, some of the surrounding particles escape moments before capture and are blown far out into space in the form of jets. 

Astronomers have relied on different models of how matter behaves near the black hole to better understand this process. But they still don’t know exactly how jets larger than the galaxy are launched from its central region, which is as small in size as the Solar System, nor how exactly matter falls into the black hole. With the new EHT image of the black hole and its shadow in polarized light, astronomers managed for the first time to look into the region just outside the black hole where this interplay between matter flowing in and being ejected out is happening. 

These observations provide new information about the structure of the magnetic fields just outside the black hole. The team found that only theoretical models featuring strongly magnetized gas can explain what they are seeing at the event horizon. Researchers at the U of I created such models.

An atmosphere is what makes life on Earth's surface possible, regulating our climate and sheltering us from damaging cosmic rays. But although telescopes have counted a growing number of rocky planets, scientists had thought most of their atmospheres long lost.

However, a new study by University of Chicago and Stanford University researchers suggests a mechanism whereby these planets could not only develop atmospheres full of water vapor, but keep them for long stretches. Published March 15, 2021 in the Astrophysical Journal Letters, the research expands our picture of planetary formation and could help direct the search for habitable worlds in other star systems.

"Our model is saying that these hot, rocky exoplanets should have a water-dominated atmosphere at some stage, and for some planets, it may be quite a long time," said Asst. Prof. Edwin Kite, an expert in how planetary atmospheres evolve over time. As telescopes document more and more exoplanets, scientists are trying to figure out what they might look like. Generally, telescopes can tell you about an exoplanet's physical size, its proximity to its star and if you're lucky, how much mass it has. To go much further, scientists have to extrapolate based on what we know about Earth and the other planets in our own solar system. But the most abundant planets don't seem to be similar to the ones we see around us.

"What we already knew from the Kepler mission is that planets a little smaller than Neptune are really abundant, which was a surprise because there are none in our solar system," Kite said. "We don't know for sure what they are made of, but there's strong evidence they are magma balls cloaked in a hydrogen atmosphere."

Albert Einstein's theory of general relativity profoundly changed our thinking about fundamental concepts in physics, such as space and time. But it also left us with some deep mysteries. One was black holes, which were only unequivocally detected over the past few years. Another was "wormholes"—bridges connecting different points in spacetime, in theory providing shortcuts for space travelers.

Wormholes are still in the realm of the imagination. But some scientists think we will soon be able to find them, too. Over the past few months, several new studies have suggested intriguing ways forward. Black holes and wormholes are special types of solutions to Einstein's equations, arising when the structure of spacetime is strongly bent by gravity. For example, when matter is extremely dense, the fabric of spacetime can become so curved that not even light can escape. This is a black hole.

As the theory allows the fabric of spacetime to be stretched and bent, one can imagine all sorts of possible configurations. In 1935, Einstein and physicist Nathan Rosen described how two sheets of spacetime can be joined together, creating a bridge between two universes. This is one kind of wormhole – and since then many others have been imagined.

Some wormholes may be "traversable", meaning humans may be able to travel through them. For that though, they would need to be sufficiently large and kept open against the force of gravity, which tries to close them. To push spacetime outward in this way would require huge amounts of "negative energy".

Sounds like sci-fi? We know that negative energy exists, small amounts have already been produced in the lab. We also know that negative energy is behind the universe's accelerated expansion. So nature may have found a way to make wormholes.

Spotting wormholes in the sky

How can we ever prove that wormholes exist? In a new paper, published in the Monthly Notices of the Royal Society, Russian astronomers suggest they may exist at the center of some very bright galaxies, and propose some observations to find them. This is based on what would happen if matter coming out of one side of the wormhole collided with matter that was falling in. The calculations show that the crash would result in a spectacular display of gamma rays that we could try to observe with telescopes.

This radiation could be the key to differentiating between a wormhole and a black hole, previously assumed to be indistinguishable from the outside. But black holes should produce fewer gamma rays and eject them in a jet, while radiation produced via a wormhole would be confined to a giant sphere. Although the kind of wormhole considered in this study is traversable, it would not make for a pleasant trip. Because it would be so close to the center of an active galaxy, the high temperatures would burn everything to a crisp. But this wouldn't be the case for all wormholes, such as those further from the galactic center.

Researchers have transported an atom between two locations in the shortest possible time, an achievement that has implications for quantum technologies.

Moving information from one place to another takes time, even in the quantum world. A team of researchers has now moved an atom in the shortest time possible, in a way that preserves the information that it contains [1]. Achieving the top overall speed turned out to require a series of accelerations and decelerations, not a constant cruise. Disturbances from the environment degrade the performance of quantum computers, and carrying out the calculations as quickly as possible is one way to reduce such effects. But running calculations too quickly can also lead to information loss, so there is a “speed limit” on such systems.

For simple, two-level quantum systems, such as an electron (which can be spin-up or spin-down), researchers have performed quantum operations at the theoretically predicted speed limits. However, some quantum technologies, such as atom interferometers, require a system to move among many quantum states. These systems should also have speed limits, but they have not been predicted or measured. Andrea Alberti of the University of Bonn in Germany and his colleagues have now studied an example of such a speed limit. They measured the fastest speed at which an atom could be moved from one place to another, ending at the new location in the same state in which it began, despite transitioning to other states during the trip. Moving too rapidly can cause the atom to end up in a different state, which means that it loses information. Keeping the information safe while moving as fast as possible is a bit like transferring a bowl containing water from one location to another at the highest possible speed that avoids a spill.

For their experiments, the team used a so-called optical lattice trap, in which atoms sit in a row of potential energy valleys produced by a pair of overlapping, oppositely directed laser beams. They used a microwave field to cool the atoms to their lowest (ground) vibrational state. In this state, each atom is like a fluid sloshing back and forth in a bowl with the smallest possible amplitude; excited states correspond to larger-amplitude oscillations. The goal was to end in the ground state, even though the atoms transitioned to excited states along the way.

To transport the atoms, the team caused the valleys to move like a conveyor belt, with each valley moving as far as its nearest neighbor. They could vary the speed of the conveyor belt, and they used measurement techniques that allowed sub-nanometer tracking of the motion. Alberti and his colleagues transported their atoms a distance of 0.5 micrometers using both constant-speed and variable-speed schemes. In each case, the researchers measured the fidelity, a parameter characterizing the similarity of the initial and final states. The protocol with the best fidelity involved a series of speedups and slowdowns. These speed “wiggles” canceled out the effects of transitions to excited states that occurred during the transport process, ensuring that the atoms ended in the ground state. This wiggling is analogous to physically wiggling a bowl containing water to counteract excessive sloshes as it is moved at high speed—tipping it forward a bit at the beginning of its journey and backward a bit at the end.

The researchers found that when the average speed over the trip was below about 17 millimeters per second, the fidelity was very good, but it dropped to much lower values for higher average speeds. The team developed a theory to explain this measured speed limit. “The finding is a compelling demonstration of how fundamental properties of quantum dynamics change when one goes beyond the well-studied case of a two-level system,” says Nora Tischler, a quantum physicist at Griffith University in Australia. “I am excited by this work,” she adds. Daniel Burgarth of Macquarie University, also in Australia, is equally impressed. He hopes that the new method will be adapted by other groups to operate complex quantum systems at or near their speed limits.

A new theoretical study has proposed a novel mechanism for the creation of supermassive black holes from dark matter. The international team find that rather than the conventional formation scenarios involving ‘normal’ matter, supermassive black holes could instead form directly from dark matter in high density regions in the centers of galaxies. The result has key implications for cosmology in the early Universe, and is published in Monthly Notices of the Royal Astronomical Society.

Exactly how supermassive black holes initially formed is one of the biggest problems in the study of galaxy evolution today. Supermassive black holes have been observed as early as 800 million years after the Big Bang, and how they could grow so quickly remains unexplained.

Standard formation models involve normal baryonic matter – the atoms and elements that that make up stars, planets, and all visible objects – collapsing under gravity to form black holes, which then grow over time. However the new work investigates the potential existence of stable galactic cores made of dark matter, and surrounded by a diluted dark matter halo, finding that the centers of these structures could become so concentrated that they could also collapse into supermassive black holes once a critical threshold is reached. According to the model this could have happened much more quickly than other proposed formation mechanisms, and would have allowed supermassive black holes in the early Universe to form before the galaxies they inhabit, contrary to current understanding.

Carlos R. Argüelles, the researcher at Universidad Nacional de La Plata and ICRANet who led the investigation comments: “This new formation scenario may offer a natural explanation for how supermassive black holes formed in the early Universe, without requiring prior star formation or needing to invoke seed black holes with unrealistic accretion rates.” Another intriguing consequence of the new model is that the critical mass for collapse into a black hole might not be reached for smaller dark matter halos, for example those surrounding some dwarf galaxies. The authors suggest that this then might leave smaller dwarf galaxies with a central dark matter nucleus rather than the expected black hole. Such a dark matter core could still mimic the gravitational signatures of a conventional central black hole, whilst the dark matter outer halo could also explain the observed galaxy rotation curves.

“This model shows how dark matter haloes could harbor dense concentrations at their centers, which may play a crucial role in helping to understand the formation of supermassive black holes,” added Carlos.

Researchers have succeeded in making an AI understand our subjective notions of what makes faces attractive. The device demonstrated this knowledge by its ability to create new portraits on its own that were tailored to be found personally attractive to individuals. The results can be utilized, for example, in modelling preferences and decision-making as well as potentially identifying unconscious attitudes.

"In our previous studies, we designed models that could identify and control simple portrait features, such as hair colour and emotion. However, people largely agree on who is blond and who smiles. Attractiveness is a more challenging subject of study, as it is associated with cultural and psychological factors that likely play unconscious roles in our individual preferences. Indeed, we often find it very hard to explain what it is exactly that makes something, or someone, beautiful: Beauty is in the eye of the beholder," says Senior Researcher and Docent Michiel Spapé from the Department of Psychology and Logopedics, University of Helsinki.

The study, which combines computer science and psychology, was published in February in the IEEE Transactions in Affective Computing journal.

Preferences exposed by the brain

Initially, the researchers gave a generative adversarial neural network (GAN) the task of creating hundreds of artificial portraits. The images were shown, one at a time, to 30 volunteers who were asked to pay attention to faces they found attractive while their brain responses were recorded via electroencephalography (EEG).

"It worked a bit like the dating app Tinder: the participants 'swiped right' when coming across an attractive face. Here, however, they did not have to do anything but look at the images. We measured their immediate brain response to the images," Spapé explains.

The researchers analysed the EEG data with machine learning techniques, connecting individual EEG data through a brain-computer interface to a generative neural network.

"A brain-computer interface such as this is able to interpret users' opinions on the attractiveness of a range of images. By interpreting their views, the AI model interpreting brain responses and the generative neural network modelling the face images can together produce an entirely new face image by combining what a particular person finds attractive," says Academy Research Fellow and Associate Professor Tuukka Ruotsalo, who heads the project.

Reference: Michiel Spape, Keith Davis, Lauri Kangassalo, Niklas Ravaja, Zania Sovijarvi-Spape, Tuukka Ruotsalo. Brain-computer interface for generating personally attractive images. IEEE Transactions on Affective Computing, 2021; 1 DOI: 10.1109/TAFFC.2021.3059043

Common fungi, often present in the gut, teach the immune system how to respond to their more dangerous relatives, according to new research from scientists at Weill Cornell Medicine.

Scientists discovered a new species of a peculiar cave-dwelling snail in one of the 20 deepest cave systems in the world, Lukina Jama–Trojama in Croatia. The newly discovered species belongs to a genus of minute air-breathing land snails that have lost visual orientation and are considered to be true eutroglobionts, or exclusive cave-dwellers.

The study describing the new species was published in the open access journal Subterranean Biology. The new species Zospeum tholussum is a miniature and fragile snail, with a beautifully shaped dome-like translucent shell. Only one living specimen was found during the expedition around the galleries of the Lukina Jama–Trojama cave system. The animal was found at the remarkable depth of 980 m, in an unnamed chamber full of rocks and sand and a small stream running through it.

All known species from the cave-dwelling genus Zospeum possess a limited ability to move. Their preference of a muddy habitat and the fact that they are usually located near the drainage system of the cave, in a close proximity to running water, however suggest that these animals are not exactly immobile. Scientists hypothesize that dispersal is achieved through passive transportation via water or larger mammals.

The Lukina Jama–Trojama is the deepest cave system in Croatia, extraordinary for its vertical shape, long pits and great depth of -1392 m. From an ecological point of view this cave system is extremely interesting for having three microclimatic layers: firstly entrance icy part with the temperature of about 1 °C, secondly, middle part with the temperature up to 2 °C and bottom part with temperature till 4 °C. These unusual living conditions make the cave extremely interesting for scientist from a biodiversity point of view.

Citation: Weigand AM (2013) New Zospeum species (Gastropoda, Ellobioidea, Carychiidae) from 980 m depth in the Lukina Jama–Trojama cave system (Velebit Mts., Croatia). Subterranean Biology 11: 45–53. doi: 10.3897/ subtbiol.11.5966

In traditional electronics, separate chips process and store data, wasting energy as they toss data back and forth over what engineers call a “memory wall.” New algorithms combine several energy-efficient hybrid chips to create the illusion of one mega–AI chip.

The torsion balance contains a rigid balance beam suspended by a fine thread as an ancient scientific instrument that continues to form a very sensitive force sensor to date. The force sensitivity is proportional to the lengths of the beam and thread and inversely proportional to the fourth power of the diameter of the thread. Therefore, nanomaterials that support the torsion balances should be ideal building blocks.

In a new report now published on Science Advances, Lin Cong and a research team in quantum physics, microelectronics and nanomaterials in China have detailed a torsional balance array on a chip with the highest sensitivity level. The team facilitated this by using a carbon nanotube as the thread and a monolayer graphene coated with aluminum films as the beam and mirror. Using the experimental setup, Cong et al. measured the femtonewton force exerted by a weak laser. The balances on the chip served as an ideal platform to investigate fundamental interactions up to zeptonewton in accuracy.

The showy colors of some butterflies could advertise their speed and nimbleness, much like a coat of bright yellow paint on a sports car. A new study shows birds can learn to recognize these visual cues, avoiding not only butterflies they've failed to nab in the past but similar-looking species as well.

The research provides some of the strongest evidence to date for the idea of evasive mimicry, a strategy in which animals protect themselves from predators by matching the colors or patterns of agile relatives. First proposed more than 60 years ago, the hypothesis has been a challenge to test. But in an experimental setting, researchers found that wild birds learned and remembered the wing patterns of artificial butterflies that evaded their attacks, as well as those that had a foul flavor, equally spurning both in follow-up tests and often ignoring lookalikes with similar color patterns. Unexpectedly, the birds learned to avoid evasive butterflies faster than distasteful ones.

The results suggest that being hard to catch may deter predators at least as effectively as chemical defenses. "There's a common idea that being distasteful is one of the best kinds of defense to have, but at least in this experiment, that didn't prove to be the case," said study co-author Keith Willmott, curator and director of the Florida Museum of Natural History's McGuire Center for Lepidoptera and Biodiversity.

Neanderthal fossils from a cave in Belgium believed to belong to the last survivors of their species ever discovered in Europe are thousands of years older than once thought, a new study said.

Previous radiocarbon dating of the remains from the Spy Cave yielded ages as recent as approximately 24,000 years ago, but the new testing pushes the clock back to between 44,200 to 40,600 years ago. The research appeared in the Proceedings of the National Academy of Sciences and was carried out by a team from Belgium, Britain and Germany.

Co-lead author Thibaut Deviese from the University of Oxford and Aix-Marseille University told AFP he and colleagues had developed a more robust method to prepare samples, which was better able to exclude contaminants. Having a firm idea of when our closest human relatives disappeared is considered a key first step toward understanding more about their nature and capabilities, as well as why they eventually went extinct while our own ancestors prospered.

The new method still relies on radiocarbon dating, long considered the gold standard of archeological dating, but refines the way specimens are collected. All living things absorb carbon from the atmosphere and their food, including the radioactive form carbon-14, which decays over time. Since plants and animals stop absorbing carbon-14 when they die, the amount that remains when they are dated tells us how long ago they lived.

Quantum technologies such as quantum computers require sources of entangled pairs of photons. To make these photon pairs, researchers commonly use silicon-based devices, where the silicon sits on an insulator.

Galan Moody and his colleagues at the University of California, Santa Barbara, wondered if they could switch the silicon with aluminum gallium arsenide (AlGaAs), a material that has recently been demonstrated to be useful for classical photonics applications. The team showed that AlGaAs-made devices can produce entangled photons at a rate 1000 times greater than devices made from other materials [1].

Chip-sized devices for producing entangled pairs of photons typically couple laser light into a photonic waveguide or an optical cavity. Individual photons in the laser are then annihilated by interacting with the cavity’s material, a process that creates two new—entangled—photons. The efficiency of this process depends on the size of the cavity and the properties of the material used to make it.

Using this same design, Moody and his colleagues tinkered with the cavity’s size and switched its material from silicon to AlGaAs. They found that they could increase the efficiency of the process significantly without compromising other important properties of the generated entangled photon pairs, such as entanglement fidelity.

The 1000-fold increase in brightness that the team achieved should, they say, let them produce the same number of entangled photon pairs as other devices but by using lower-power lasers. That could allow the modified devices to consume less power overall. AlGaAs could also be used to make the other components for quantum computers, potentially allowing them to be contained on a single chip. The team says that such integration would simplify device fabrication and facilitate all-on-chip quantum-photonics systems.

As light as possible and as strong as possible at the same time. These are the requirements for modern lightweight materials, such as those used in aircraft construction and the automotive industry. A research team has now developed a new materials' design approach for future ultralight materials: Nanometer-sized metal struts that form nested networks on separate hierarchical levels provide amazing strength.

When the Eiffel Tower was inaugurated in 1889, it was considered a technical marvel. Its artful and delicate arrangement of large and small iron girders provided extraordinary stability and made sure it became the world's tallest building at the time by a long shot. "Hierarchical" is what experts call the engineering approach of an open array of larger beams braced by smaller ones. For several years now, material science researchers have tried to transfer this efficient approach to the internal microstructure of materials, for example by using 3D printers that can replicate engineering truss structures on a micrometer scale.

So far, hopes of creating a new generation of extremely strong lightweight construction materials have not been fulfilled. One of the reasons: "A 3D printer can only print a maximum of roughly ten thousand beams and that will take hours," according to Professor Jörg Weißmüller of the Institute of Materials Mechanics at HZG, co-author of the current publication. "For practical applications, this is not really a viable option."

Corroding away silver

Nevertheless, his team is pursuing an even more ambitious goal. The vision: If beams could be strengthened by downsizing to few nanometers in diameter, they could provide the basis for a new type of material -- exceptionally light and at the same time strong. However, this kind of material would have to contain trillions of beams, far exceeding the capability of even the most sophisticated printer. "That is why we have to trick nature into making these kinds of materials for us, simply by self-organization," Weißmüller's colleague Dr. Shan Shi, lead author of the study, explains.

As a start, the team used an alloy of 93% silver and 7% gold. This alloy is dipped into diluted sulfuric acid, dissolving out approximately half of the silver. As a result, the remaining material rearranges itself, forming a delicate network of nanoscale beams. Afterwards, the material undergoes a heat treatment at several hundred degrees. "This coarsens the network to a beam size of 150 nanometers while maintaining the original architecture," Shi explains. During the last step, acid comes into play once again. It is used to wash out the rest of the silver, leaving only gold beams with a pore size of 15 nanometers on average. The result is a hierarchically structured material with two distinctly different beam sizes, not unlike the Eiffel Tower. As a result of its open network structure, this new material consists of 80 to 90% air, giving it a density of only 10 to 20% of the solid metal.

Ever get stuck trying to solve a puzzle? You look for a pattern, or a rule, and you just can't spot it. So you back up and start over. That's your brain recognizing that your current strategy isn't working, and that you need a new way to solve the problem, according to new research from the University of Washington. With the help of about 200 puzzle-takers, a computer model and functional MRI (fMRI) images, researchers have learned more about the processes of reasoning and decision-making, pinpointing the brain pathway that springs into action when problem-solving goes south.

"There are two fundamental ways your brain can steer you through life -- toward things that are good, or away from things that aren't working out," said Chantel Prat, associate professor of psychology and co-author of the new study, published Feb. 23 2021, in the journal Cognitive Science. "Because these processes are happening beneath the hood, you're not necessarily aware of how much driving one or the other is doing." Using a decision-making task developed by Michael Frank at Brown University, the researchers measured exactly how much "steering" in each person's brain involved learning to move toward rewarding things as opposed to away from less-rewarding things. Prat and her co-authors were focused on understanding what makes someone good at problem-solving.

The research team first developed a computer model that specified the series of steps they believed were required for solving the Raven's Advanced Performance Matrices (Raven's) -- a standard lab test made of puzzles like the one above. To succeed, the puzzle-taker must identify patterns and predict the next image in the sequence. The model essentially describes the four steps people take to solve a puzzle:

UCSD researchers have discovered a single gene alteration that may help explain cognitive differences between modern humans and our predecessor, and used that information to develop Neanderthal-like brain organoids in the lab.

As a professor of pediatrics and cellular and molecular medicine at University of California San Diego School of Medicine, Alysson R. Muotri, PhD, has long studied how the brain develops and what goes wrong in neurological disorders. For almost as long, he has also been curious about the evolution of the human brain -- what changed that makes us so different from preceding Neanderthals and Denisovans, our closest evolutionary relatives, now extinct?

Evolutionary studies rely heavily on two tools -- genetics and fossil analysis -- to explore how a species changes over time. But neither approach can reveal much about brain development and function because brains do not fossilize, Muotri said. There is no physical record to study.

New research shows that slight alterations in transfer-RNA molecules (tRNAs) allow them to self-assemble into a functional unit that can replicate information exponentially. tRNAs are key elements in the evolution of early life-forms.

A Ludwig-Maximilians-Universitaet (LMU) in Munich team has shown that slight alterations in transfer-RNA molecules (tRNAs) allow them to self-assemble into a functional unit that can replicate information exponentially. tRNAs are key elements in the evolution of early life-forms.

Life as we know it is based on a complex network of interactions, which take place at microscopic scales in biological cells, and involve thousands of distinct molecular species. In our bodies, one fundamental process is repeated countless times every day. In an operation known as replication, proteins duplicate the genetic information encoded in the DNA molecules stored in the cell nucleus -- before distributing them equally to the two daughter cells during cell division. The information is then selectively copied ('transcribed') into what are called messenger RNA molecules (mRNAs), which direct the synthesis of the many different proteins required by the cell type concerned. A second type of RNA -- transfer RNA (tRNA) -- plays a central role in the 'translation' of mRNAs into proteins. Transfer RNAs act as intermediaries between mRNAs and proteins: they ensure that the amino-acid subunits of which each particular protein consists are put together in the sequence specified by the corresponding mRNA.

How could such a complex interplay between DNA replication and the translation of mRNAs into proteins have arisen when living systems first evolved on the early Earth? We have here a classical example of the chicken-and-the-egg problem: Proteins are required for transcription of the genetic information, but their synthesis itself depends on transcription.

LMU physicists led by Professor Dieter Braun have now demonstrated how this conundrum could have been resolved. They have shown that minor modifications in the structures of modern tRNA molecules permit them to autonomously interact to form a kind of replication module, which is capable of exponentially replicating information. This finding implies that tRNAs -- the key intermediaries between transcription and translation in modern cells -- could also have been the crucial link between replication and translation in the earliest living systems. It could therefore provide a neat solution to the question of which came first -- genetic information or proteins?

Strikingly, in terms of their sequences and overall structure, tRNAs are highly conserved in all three domains of life, i.e. the unicellular Archaea and Bacteria (which lack a cell nucleus) and the Eukaryota (organisms whose cells contain a true nucleus). This fact in itself suggests that tRNAs are among the most ancient molecules in the biosphere.

The company NanoViricides, Inc. is taking a unique approach to fighting herpes (shingles) and other viral infections by using tiny decoys, termed nanoviricides, to bind and inactivate the virus.

Nanoviricides are composed of micelles with up to 1,200 chemically attached ligands on their surface. These ligands mimic the cellular receptors targeted by the relevant virus or class of virus. When a virion is bound by a nanoviricide via the virion’s cell-receptor-binding glycoproteins, the lipid envelope of the virus merges with the lipids attached to the nanoviricide. This lipid mixing destabilizes the virion, rendering it incapable of infecting host cells.

NanoViricides’ shingles drug candidate is moving rapidly toward the clinic as a topical treatment for shingles. The company also has related drug candidates with follow-on applications against other herpes infections in its HerpeCide program.

According to Anil R. Diwan, NanoViricides’ president and chairman, “our anti-herpes drug development program has produced impressive results in animal models and, with limited additional testing, we are close to declaring a drug candidate that will move into clinical testing.”

Indeed, a nanoviricide against HSV-1 has shown impressive activity in mice, providing proof of concept for the success of similar drugs in humans. Because nanoviricides attack viruses directly, the host environment is not expected to affect their activity. In experiments performed in the laboratory of Ken Rosenthal at Northeast Ohio Medical University, mice were infected with the highly virulent H129c strain of HSV-1, which is uniformly fatal. However, in mice treated with an anti-herpes nanoviricide, viral load dropped by 99.9%, lesion progression was halted, and >85% of the mice survived.