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May 29, 2020

A giant galaxy in the young Universe with a massive ring

Posted by in categories: evolution, space

In the local (redshift z ≈ 0) Universe, collisional ring galaxies make up only ~0.01% of galaxies1 and are formed by head-on galactic collisions that trigger radially propagating density waves2,3,4. These striking systems provide key snapshots for dissecting galactic disks and are studied extensively in the local Universe5,6,7,8,9. However, not much is known about distant (z 0.1) collisional rings10,11,12,13,14. Here we present a detailed study of a ring galaxy at a look-back time of 10.8 Gyr (z = 2.19). Compared with our Milky Way, this galaxy has a similar stellar mass, but has a stellar half-light radius that is 1.5–2.2 times larger and is forming stars 50 times faster. The extended, diffuse stellar light outside the star-forming ring, combined with a radial velocity on the ring and an intruder galaxy nearby, provides evidence for this galaxy hosting a collisional ring. If the ring is secularly evolved15,16, the implied large bar in a giant disk would be inconsistent with the current understanding of the earliest formation of barred spirals17,18,19,20,21. Contrary to previous predictions10,11,12, this work suggests that massive collisional rings were as rare 11 Gyr ago as they are today. Our discovery offers a unique pathway for studying density waves in young galaxies, as well as constraining the cosmic evolution of spiral disks and galaxy groups.

May 29, 2020

Hippocampal Network Reorganization Underlies the Formation of a Temporal Association Memory

Posted by in category: neuroscience

Episodic memory requires linking events in time, a function dependent on the hippocampus. In “trace” fear conditioning, animals learn to associate a neutral cue with an aversive stimulus despite their separation in time by a delay period on the order of tens of seconds. But how this temporal association forms remains unclear. Here we use two-photon calcium imaging of neural population dynamics throughout the course of learning and show that, in contrast to previous theories, hippocampal CA1 does not generate persistent activity to bridge the delay. Instead, learning is concomitant with broad changes in the active neural population. Although neural responses were stochastic in time, cue identity could be read out from population activity over longer timescales after learning. These results question the ubiquity of seconds-long neural sequences during temporal association learning and suggest that trace fear conditioning relies on mechanisms that differ from persistent activity accounts of working memory.

May 29, 2020

BRIAN KENNEDY — Reversing Human Aging (#0004)

Posted by in categories: biotech/medical, genetics, life extension, robotics/AI

Sirtuins, telomeres, A.I. experiment with vitamin A and personalized medicine, a bit of everything here.


https://facebook.com/LongevityFB https://instagram.com/longevityyy

https://linkedin.com/company/longevityy

Continue reading “BRIAN KENNEDY — Reversing Human Aging (#0004)” »

May 28, 2020

NSA: Russia’s Sandworm Hackers Have Hijacked Mail Servers

Posted by in categories: cybercrime/malcode, privacy

A warning that hackers are exploiting vulnerable email servers doesn’t qualify as an unusual event in general. But when that warning comes from the National Security Agency, and the hackers are some of the most dangerous state-sponsored agents in the world, run-of-the-mill email server hacking becomes significantly more alarming.

On Thursday, the NSA issued an advisory that the Russian hacker group known as Sandworm, a unit of the GRU military intelligence agency, has been actively exploiting a known vulnerability in Exim, a commonly used mail transfer agent—an alternative to bigger players like Exchange and Sendmail—running on email servers around the world. The agency warns that Sandworm has been exploiting vulnerable Exim mail servers since at least August 2019, using the hacked servers as an initial infection point on target systems and likely pivoting to other parts of the victim’s network. And while the NSA hasn’t said who those targets have been, or how many there are, Sandworm’s history as one of the most aggressive and destructive hacking organizations in the world makes any new activity from the group worth noting.

“We still consider this to be one of the most, if not the most aggressive and potentially dangerous actor that we track,” says John Hultquist, the director of intelligence at FireEye, who also led a team at iSight Partners when that company first discovered and named Sandworm in 2014.

May 28, 2020

NSA warns of new Sandworm attacks on email servers

Posted by in categories: cybercrime/malcode, privacy

The US National Security Agency (NSA) has published today a security alert warning of a new wave of cyberattacks against email servers, attacks conducted by one of Russia’s most advanced cyber-espionage units.

The NSA says that members of Unit 74455 of the GRU Main Center for Special Technologies (GTsST), a division of the Russian military intelligence service, have been attacking email servers running the Exim mail transfer agent (MTA).

Also known as “Sandworm,” this group has been hacking Exim servers since August 2019 by exploiting a critical vulnerability tracked as CVE-2019–10149, the NSA said in a security alert [PDF] shared today with ZDNet.

May 28, 2020

‘Satellite catcher’ will use magnets to clean up space junk

Posted by in category: space

Circa 2017


Japanese scientists are developing a system to capture and remove space debris.

May 28, 2020

The Air Force is experimenting with turning cargo planes into flying munitions trucks

Posted by in category: transportation

Editor’s Note: This article originally appeared on Business Insider.

The U.S. Air Force has been experimenting with turning its cargo and transport planes into munitions trucks able to drop devastating bundles of standoff weaponry, the service has revealed.

The Air Force Research Laboratory said Wednesday that Air Force Special Operations Command successfully dropped simulated palletized munitions from a MC-130J Commando II multi-mission combat transport/special operations tanker in a test at Dugway Proving Ground in Utah in January.

May 28, 2020

The Last Time This Happened, Bitcoin Surged From $3,150 to $14,000

Posted by in category: bitcoin

In 2019, the price of Bitcoin surged from $3,150 to $14,000 when the inflow of BTC into exchanges plunged, and it just happened again.

May 28, 2020

Scientists create virus that has potential to fight cancer

Posted by in categories: bioengineering, biotech/medical, genetics

Not all viruses set out to cause widespread death and sickness — some have the potential to fight cancer, according to new research.

Researchers from Hokkaido University in Japan have genetically engineered adenoviruses, which is a family of viruses that cause mild symptoms, to replicate inside cancer cells and kill them, according to a new paper in the journal Cancers.

To do this, Fumihiro Higashino, a molecular oncologist, and his team inserted adenylate-uridylate-rich elements (AREs) from two human genes — a stabilizing element found in a type of macromolecule present in all biological cells — into two strains of the virus to help specifically attack cancer cells.

May 28, 2020

How the U.S. Is Quietly Winning the Hypersonic Arms Race

Posted by in category: military

The Russians have their Avangard missiles and the Chinese have a railgun, but the Americans have developed maneuverable hypersonic shells for their existing artillery.