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Dec 7, 2023

The Virus Zoo: A Primer on Molecular Virology

Posted by in categories: biotech/medical, genetics

Genome and Structure:

HIV’s genome is a 9.7 kb linear positive-sense ssRNA.1 There is a m7G-cap (specifically the standard eukaryotic m7GpppG as added by the host’s enzymes) at the 5’ end of the genome and a poly-A tail at the 3’ end of the genome.2 The genome also has a 5’-LTR and 3’-LTR (long terminal repeats) that aid its integration into the host genome after reverse transcription, that facilitate HIV genetic regulation, and that play a variety of other important functional roles. In particular, it should be noted that the integrated 5’UTR contains the HIV promoter called U3.3,4

HIV’s genome translates three polyproteins (as well as several accessory proteins). The Gag polyprotein contains the HIV structural proteins. The Gag-Pol polyprotein contains (within its Pol component) the enzymes viral protease, reverse transcriptase, and integrase. The Gag-Pol polyprotein is produced via a −1 ribosomal frameshift at the end of Gag translation. Because of the lower efficiency of this frameshift, Gag-Pol is synthesized 20-fold less frequently than Gag.5 The frameshift’s mechanism depends upon a slippery heptanucleotide sequence UUUUUUA and a downstream RNA secondary structure called the frameshift stimulatory signal (FSS).6 This FSS controls the efficiency of the frameshift process.

Dec 7, 2023

Fractal photonic anomalous Floquet topological insulators to generate multiple quantum chiral edge states

Posted by in categories: evolution, quantum physics

An anomalous Floquet topological insulator (AFTI) is a periodically driven topological insulator (TI with nonzero winding numbers to support topological edge modes, though its standard topological invariants like Chern numbers are zero.

The photonic constructed by an optical array fabricated by the femtosecond laser direct writing (FLDW) is an important platform for to realize photonic AFTIs, because the FLDW offers flexible design of true three-dimensional (3D) waveguide structures and precise control of each coupling between waveguides. Moreover, the evolution distance of the lattice can be mapped as the evolution time.

In -direct-written photonic AFTIs, selective coupling of adjacent waveguides in a cycle is explicitly defined by the discrete periodically driving protocol. At the complete transfer discrete driving protocol, chiral edge modes co-exist with dispension-less bulk modes, and the lattice energy transfer efficiency of the chiral edge mode is the highest among all TIs (close to 100%), so it is very suitable for the transport of fragile quantum states.

Dec 7, 2023

Polaritons open up a new lane on the semiconductor highway

Posted by in categories: engineering, nanotechnology, particle physics, quantum physics

On the highway of heat transfer, thermal energy is moved by way of quantum particles called phonons. But at the nanoscale of today’s most cutting-edge semiconductors, those phonons don’t remove enough heat. That’s why Purdue University researchers are focused on opening a new nanoscale lane on the heat transfer highway by using hybrid quasiparticles called “polaritons.”

Thomas Beechem loves . He talks about it loud and proud, like a preacher at a big tent revival.

“We have several ways of describing energy,” said Beechem, associate professor of mechanical engineering. “When we talk about light, we describe it in terms of particles called ‘photons.’ Heat also carries energy in predictable ways, and we describe those waves of energy as ‘phonons.’ But sometimes, depending on the material, photons and phonons will come together and make something new called a ‘.’ It carries energy in its own way, distinct from both photons or phonons.”

Dec 7, 2023

Google’s New Gemini Model: Achieving Human Expert Performance 🚀

Posted by in category: robotics/AI

Google launched Gemini, their GPT4 killer, and it beats GPT4 in almost every way. Some of the demos are absolutely insane. Let’s go over all the news! Enjoy smile Become a Patron 🔥 — https://patreon.com/MatthewBerman Join the Discord 💬 — https://discord.gg/xxysSXBxFW Follow me on Twitter 🧠 — https://twitter.com/matthewberman Subscribe to my Substack 🗞️ — https://matthewberman.substack.com/ Media/Sponsorship Inquiries 📈 — https://bit.ly/44TC45V Need AI Consulting? ✅ — https://forwardfuture.ai/ Massed Compute (GPU Rental) 🚀 — https://bit.ly/matthew-berman-youtube Links: https://www.youtube.com/watch?v=jV1vkHv4zq8 https://developers.googleblog.com/2023/12/how-its-made-gemin…pting.html https://deepmind.google/technologies/gemini/#introduction https://www.youtube.com/watch?v=UIZAiXYceBI https://www.youtube.com/watch?v=sPiOP_CB54A https://www.youtube.com/watch?

Dec 7, 2023

Time’ May Explain Why Gravity Won’t Play by Quantum Rules

Posted by in categories: cosmology, particle physics, quantum physics

A new theory suggests that the unification between quantum physics and general relativity has eluded scientists for 100 years because huge “fluctuations” in space and time mean that gravity won’t play by quantum rules.

Since the early 20th century, two revolutionary theories have defined our fundamental understanding of the physics that governs the universe. Quantum physics describes the physics of the small, at scales tinier than the atom, telling us how fundamental particles like electrons and photons interact and are governed. General relativity, on the other hand, describes the universe at tremendous scales, telling us how planets move around stars, how stars can die and collapse to birth black holes, and how galaxies cluster together to build the largest structures in the cosmos.

Dec 7, 2023

Quantum ‘magic’ could help explain the origin of spacetime

Posted by in categories: cosmology, mathematics, particle physics, quantum physics

A quantum property dubbed “magic” could be the key to explaining how space and time emerged, a new mathematical analysis by three RIKEN physicists suggests. The research is published in the journal Physical Review D.

It’s hard to conceive of anything more basic than the fabric of spacetime that underpins the universe, but have been questioning this assumption. “Physicists have long been fascinated about the possibility that space and time are not fundamental, but rather are derived from something deeper,” says Kanato Goto of the RIKEN Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS).

This notion received a boost in the 1990s, when theoretical physicist Juan Maldacena related the gravitational theory that governs spacetime to a theory involving . In particular, he imagined a hypothetical space—which can be pictured as being enclosed in something like an infinite soup can, or “bulk”—holding objects like that are acted on by gravity. Maldacena also imagined particles moving on the surface of the can, controlled by . He realized that mathematically a used to describe the particles on the boundary is equivalent to a gravitational theory describing the black holes and spacetime inside the bulk.

Dec 7, 2023

Wormholes help resolve black hole information paradox

Posted by in categories: cosmology, mathematics, quantum physics

A RIKEN physicist and two colleagues have found that a wormhole—a bridge connecting distant regions of the Universe—helps to shed light on the mystery of what happens to information about matter consumed by black holes.

Einstein’s theory of predicts that nothing that falls into a black hole can escape its clutches. But in the 1970s, Stephen Hawking calculated that black holes should emit radiation when , the theory governing the microscopic realm, is considered. “This is called black hole evaporation because the black hole shrinks, just like an evaporating water droplet,” explains Kanato Goto of the RIKEN Interdisciplinary Theoretical and Mathematical Sciences.

This, however, led to a paradox. Eventually, the black hole will evaporate entirely—and so too will any information about its swallowed contents. But this contradicts a fundamental dictum of quantum physics: that information cannot vanish from the Universe. “This suggests that general relativity and quantum mechanics as they currently stand are inconsistent with each other,” says Goto. “We have to find a unified framework for quantum gravity.”

Dec 7, 2023

Resolving the black hole ‘fuzzball or wormhole’ debate

Posted by in categories: cosmology, particle physics, quantum physics

Black holes really are giant fuzzballs, a new study says.

The study attempts to put to rest the debate over Stephen Hawking’s famous information paradox, the problem created by Hawking’s conclusion that any data that enters a black hole can never leave. This conclusion accorded with the laws of thermodynamics, but opposed the fundamental laws of quantum mechanics.

“What we found from is that all the mass of a black hole is not getting sucked in to the center,” said Samir Mathur, lead author of the study and professor of physics at The Ohio State University. “The black hole tries to squeeze things to a point, but then the particles get stretched into these strings, and the strings start to stretch and expand and it becomes this fuzzball that expands to fill up the entirety of the black hole.”

Dec 7, 2023

Black holes really just ever-growing balls of string, researchers say

Posted by in categories: cosmology, physics

Black holes aren’t surrounded by a burning ring of fire after all, suggests new research.

Some physicists have believed in a “firewall” around the perimeter of a black hole that would incinerate anything sucked into its powerful gravitational pull.

But a team from The Ohio State University has calculated an explanation of what would happen if an electron fell into a typical black hole, with a mass as big as the sun.

Dec 7, 2023

What’s on the surface of a black hole? Not ‘firewall’—and nature of universe depends on it, physicist explains

Posted by in category: cosmology

Are black holes the ruthless killers we’ve made them out to be?

Samir Mathur says no.

According to the professor of physics at The Ohio State University, the recently proposed idea that have “firewalls” that destroy all they has a loophole.