Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog – Page 2380

The advancement of higher cognitive abilities in humans is predominantly associated with the growth of the neocortex, a brain area key to conscious thinking, movement, and sensory perception. Researchers are increasingly realizing, however, that the “little brain” or cerebellum also expanded during evolution and probably contributes to the capacities unique to humans, explains Prof. Henrik Kaessmann from the Center for Molecular Biology of Heidelberg University.

His research team has – together with Prof. Dr Stefan Pfister from the Hopp Children’s Cancer Center Heidelberg – generated comprehensive genetic maps of the development of cells in the cerebella of humans, mice, and opossums. Comparisons of these data reveal both ancestral and species-specific cellular and molecular characteristics of cerebellum development spanning over 160 million years of mammalian evolution.

Read more | >

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.

Read more | >

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.

Read more | >

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.”

Read more | >