Lifeboat Foundation

Photosynthetic light-harvesting antennae transfer energy toward reaction centers with high efficiency, but in high light or oxidative environments, the antennae divert energy to protect the photosynthetic apparatus. For a decade, quantum effects driven by vibronic coupling, where electronic and vibrational states couple, have been suggested to explain the energy transfer efficiency, but questions remain whether quantum effects are merely consequences of molecular systems. Here, we show evidence that biology tunes interpigment vibronic coupling, indicating that the quantum mechanism is operative in the efficient transfer regime and exploited by evolution for photoprotection. Specifically, the Fenna–Matthews–Olson complex uses redox-active cysteine residues to tune the resonance between its excitons and a pigment vibration to steer excess excitation toward a quenching site.

Photosynthetic species evolved to protect their light-harvesting apparatus from photoxidative damage driven by intracellular redox conditions or environmental conditions. The Fenna–Matthews–Olson (FMO) pigment–protein complex from green sulfur bacteria exhibits redox-dependent quenching behavior partially due to two internal cysteine residues. Here, we show evidence that a photosynthetic complex exploits the quantum mechanics of vibronic mixing to activate an oxidative photoprotective mechanism. We use two-dimensional electronic spectroscopy (2DES) to capture energy transfer dynamics in wild-type and cysteine-deficient FMO mutant proteins under both reducing and oxidizing conditions. Under reducing conditions, we find equal energy transfer through the exciton 4–1 and 4–2–1 pathways because the exciton 4–1 energy gap is vibronically coupled with a bacteriochlorophyll-a vibrational mode.

Transistors, devices that can amplify, conduct or switch electronic signals or electric current, are key components of many electronics on the market today. These devices can be fabricated using a variety of inorganic and organic semiconducting materials.

Metals are generally considered unsuitable for fabricating transistors, as they screen electric fields and thus make it difficult to realize devices with tunable electrical conductivity. A possible way to create electronic components based on metals is to use gradients of counterions in films of metal nanoparticles functionalized with charged organic ligands.

In the past, engineers have successfully used this strategy to create a variety of devices, ranging from resistors to diodes and sensors. Nonetheless, modulating the electrical conductivity of these devices has often proved to be very challenging.

These shifting dynamics in India’s digital marketplace are yet another warning sign of what’s been dubbed the splinternet, foreshadowing a possible world where each country sticks to its own apps and abandons the open and global nature of the internet. For now, however, these homegrown apps may find it difficult to compete at the same level unless the government decides to ban Facebook and Twitter, too.

While Twitter finds itself in a prolonged standoff with the Indian government over the company’s refusal to take down certain accounts, a senior executive of a very similar Indian social network says the sudden attention on his app has been “overwhelming.”

“It feels like … you’ve just been put in the finals of the World Cup suddenly and everyone’s watching you and the team,” Mayank Bidawatka, co-founder of Koo, told CNN Business.

Continue reading “India is trying to build its own internet” »

Summary: A newly developed AI tool can identify “deepfakes” of faces by examining the light reflection in the eyes of the images. The system is 94% accurate at detecting deepfakes.

Source: University ay Buffalo.

University at Buffalo computer scientists have developed a tool that automatically identifies deepfake photos by analyzing light reflections in the eyes.

The State of the Edge report is based on analysis of the potential growth of edge infrastructure from the bottom up across multiple sectors modeled by Tolaga Research. The forecast evaluates 43 use cases spanning 11 vertical industries.

The one thing these use cases have in common is a growing need to process and analyze data at the point where it is being created and consumed. Historically, IT organizations have deployed applications that process data in batch mode overnight. As organizations embrace digital business transformation initiatives, it’s becoming more apparent that data needs to be processed and analyzed at the edge in near real time.

Of course, there are multiple classes of edge computing platforms, ranging from smartphones and internet of things (IoT) gateways to complete hyperconverged infrastructure (HCI) platforms that are being employed to process data at scale at the edge of a telecommunications network.

Technology paves way for intelligent solar cells, other highly efficient devices programmed at the macro and nano scale.

Researchers at Tufts University School of Engineering have created light-activated composite devices able to execute precise, visible movements and form complex three-dimensional shapes without the need for wires or other actuating materials or energy sources. The design combines programmable photonic crystals with an elastomeric composite that can be engineered at the macro and nano scale to respond to illumination.

Continue reading “‘Photonic Sunflower’ – Controlled by Light Alone, New Smart Materials Twist, Bend and Move” »

Physicists exploring the quantum world watched the birth of a quasiparticle, shedding light on the strange behavior of these strange “fake particles.”

According to a NASA blog post, the M91 is one of over a thousand galaxies that make up the Virgo cluster — a group of galaxies that are gravitationally bound to one another.

Earth is destined for disaster. This is a good insurance policy.

In 2013, a cataclysmic meteor the size of a six-story building broke apart above Chelyabinsk, Russia, and the resulting blast was stronger than a nuclear explosion. In 2068, astronomers believe a potentially hazardous “God of Chaos” asteroid could slam into Earth. Both events suggest humans—and every other animal and plant on Earth—are much more susceptible to total annihilation than we think.

Continue reading “Scientists Are Planning to Build Noah’s Ark on the Moon” »