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Fri, 21 Jan 2022
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Comet 2

Asteroid the size of two Empire State Buildings approaching Earth

Asteroid (7482) 1994 PC1
© Sormano Astronomical Observatory
Asteroid (7482) 1994 PC1 during a flyby of Earth in 1997.
A massive asteroid from NASA's 'potentially hazardous' list that is two and a half times the height of New York's Empire State Building is set to pass Earth later this month.

With an estimated diameter of at least a kilometer, asteroid (7482) 1994 PC1 is capable of causing a worldwide cataclysm if it strikes our planet. However, the chances of that happening are extremely low.

It's expected to pass some 1.98 million kilometers away from Earth - that's roughly five times the distance between our planet and the Moon - on January 18.

Comment: Not everyone at NASA would seem to agree with the recent analysis: NASA chief: Risk of asteroid impact not being taken seriously, international cooperation needed to meet cosmic threat


Fish

Bacterial Flagellum Demonstrates the Explanatory and Predictive Power of Engineering Models

Bacterial flagellar motor
© Illustra Media
irreducible complexityImage: Bacterial flagellar motor, from Unlocking the Mystery of Life.
Computer scientist and engineer Dean Schulz has published two papers in the journal BIO-Complexity that describe his top-down and bottom-up analyses of the bacterial flagellum (here, here). He recently published his final paper in the series, "An Engineering Perspective on the Bacterial Flagellum: Part 3 — Observations," which synthesizes the two approaches. Schulz's observations and conclusions demonstrate the explanatory and predictive power of engineering-based models of living systems.

The Rotary System

The bacterial flagellum functions as a rotary propulsion system in bacteria. It employs many stunningly complex subsystems. To name but a few, assembly is directed by a genetic network that ensures the manufacture of the right proteins in the right quantities at the right time. The proteins that compose the propeller are transported across the cell membrane through a transport gate that only allows the correct ones through at the correct time based on protein signal sequences. Other proteins assemble the hook and propeller (here, here). Another protein acts as a ruler that coordinates with the gate to ensure that the flagellar hook extends to the correct length. And a navigational control system controls the rotation of the rotary motor.

Comment: See also:


Galaxy

Is math a fundamental part of Nature, not something humans came up with?

Seashells display the Fibonacci  sequence

Seashells display a Golden Spiral
Nature is an unstoppable force, and a beautiful one at that. Everywhere you look, the natural world is laced with stunning patterns that can be described with mathematics. From bees to blood vessels, ferns to fangs, math can explain how such beauty emerges.

Math is often described this way, as a language or a tool that humans created to describe the world around them, with precision.

But there's another school of thought which suggests math is actually what the world is made of; that nature follows the same simple rules, time and time again, because mathematics underpins the fundamental laws of the physical world.

Comment:


Smiley

Geek fun: The physics of Wile E. Coyote's 10 billion-volt electromagnet

wile e coyote iron magnet carrot
© Warner Brothers
Wile E. Coyote hatches a plot
The famous cartoon schemer has an ingenious plan to lure Bugs Bunny out of his hole — and it involves a giant magnet and an iron carrot.

I like to analyze the physics of science fiction, and so I'm going to argue that the Merrie Melodies cartoon "Compressed Hare" takes place in the far future when animals rule the world. I mean, Bugs Bunny and Wile E. Coyote walk on two legs, talk, and build stuff. How would that not be science fiction?

Let me set the scene — and I don't think we have to worry about spoiler alerts since this episode is 60 years old. The basic idea is, of course, that Wile E. Coyote has decided he should eat the rabbit. After a couple of failed attempts to capture Bugs, he comes up with a new plan. First, he's going to drop a carrot-shaped piece of iron into Bugs' rabbit hole. After the carrot is consumed (and I have no idea how that would happen), Wile E. Coyote will turn on a giant electromagnet and pull the rabbit right to him. It's such a simple and awesome plan, it just has to work, right?

Comment: Even more fun, though sadly, scientifically inaccurate. The original clip:




Microscope 1

Not as simple as thought: How bacteria form membrane vesicles

Corynebacterium glutamicum vesicle formation
© University of Tsukuba
Corynebacterium glutamicum.
Researchers from the University of Tsukuba identified a novel mechanism by which bacteria form membrane vesicles, which bacteria employ to communicate with each other or to defend themselves against antibiotics. By studying mycolic acid-containing bacteria (MCB), which also includes tuberculosis-causing bacteria, the researchers demonstrated that environmental stimuli dictate the route by which the MCB form membrane vesicles. Further, their observations were consistent among various MCB. This study has implications for vaccine development as well as novel therapies.

Bacteria have the ability to form membrane vesicles to communicate with each other, but also to defend themselves against antibiotics. In a new study, researchers from the University of Tsukuba discovered a novel mechanism by which mycolic acid-containing bacteria, a specific group of bacteria with a special type of cell membrane, form membrane vesicles.

Arrow Up

Long periods of time in space can lead to declining mental health

Astronaut
© Robert - stock.adobe.com
Houston — Long-term space travel could lead to a spiral into mental health problems for astronauts mired in loneliness, according to research carried out on isolated workers in the Antarctic. The study shows that after long periods of time there was a lack of positive emotions and no "bounce-back" effect even when the workers were preparing to go home. Researchers say this could endanger future space missions, as positive emotions and hope are crucial to returning in a high-pressure environment like a spacecraft.

Scientists from the University of Houston came up with a checklist for detecting mental health changes in isolated, confined, and extreme (ICE) environments, and asked people working on two Antarctic stations to self-report their mental state. They found that positive emotions declined over the months and as time went on participants were less likely to use strategies to boost their mood.

"The most marked alterations were observed for positive emotions such that we saw continuous declines from the start to the end of the mission, without evidence of a 'bounce-back effect' as participants were preparing to return home," explains Candice Alfano, a professor of psychology at Houston, whose team developed the Mental Health Checklist (MHCL) in a statement.

"Previous research both in space and in polar environments has focused almost exclusively on negative emotional states including anxiety and depressive symptoms, but positive emotions such as satisfaction, enthusiasm, and awe are essential features for thriving in high-pressure settings," she continues. "Both the use of savoring — purposely noticing, appreciating, and/or intensifying positive experiences and emotions — and reappraisal — changing the way one thinks about a situation — decreased during later mission months compared to baseline. These changes likely help explain observed declines in positive emotions over time."

Arrow Up

MIB Neuralizer already exist!

MIB Neuralizer
© YouTube

When an important document lands on your desk, you might file it away for safekeeping. The same thing happens with our memories: they first appear in one part of the brain and then move to another for long-term storage in a process known as memory consolidation.

Publishing in the journal Science, Kyoto University's Akihiro Goto uses mouse brains to demonstrate a new neural-optic system to manipulate memories. The technique hinders nerve activity -- known as long-term potentiation or LTP -- which would otherwise consolidate memory during sleep.

LTP strengthens synapses through neural activity and is critical for memory formation. When and where memories are formed in the brain can be determined by examining when and which cells undergo LTP.

Drugs can disrupt LTP, but they have a general effect and are not good at targeting specific brain regions at specific time points in memory consolidation.

Looking for inspiration, Goto turned to Hollywood.

"In Men in Black the agents erase memories with a light flash. We did something similar," he says with a smile. His team uses light to deactivate proteins essential for LTP.

Mr. Potato

Tumblr hits users with new censorship rules

Tumblr
© Rob Kim/Getty Images for Tumblr
Tumblr's latest update to its iOS app, released on Tuesday, has censored a long list of seemingly harmless words to comply with Apple's new strict safety guidelines for programs featured on the tech giant's online store.

The expanded list of censored tags is apparently intended to protect users from sensitive content when searching through the platform, or when looking at its 'Stuff for You' and 'Following' sections.

As a consequence, posts containing tags that are now censored are less likely to appear when users are looking through Tumblr, reducing search results and returning a note that says, "This content has been hidden."

Telescope

Astronomers capture black hole eruption spanning 16 times the full Moon in the sky

Centaurus A
© Ben McKinley, ICRAR/Curtin and Connor Matherne, Louisiana State University.
Astronomers have produced the most comprehensive image of radio emission from the nearest actively feeding supermassive black hole to Earth.

The emission is powered by a central black hole in the galaxy Centaurus A, about 12 million light years away.

As the black hole feeds on in-falling gas, it ejects material at near light-speed, causing 'radio bubbles' to grow over hundreds of millions of years.

When viewed from Earth, the eruption from Centaurus A now extends eight degrees across the sky — the length of 16 full Moons laid side by side.

Quenelle - Golden

Nimble Chinese satellite grabs hi-res images of US city in seconds

Beijing-3 satellite
© Yang Fang, Spacecraft Engineering journal
Images taken by Beijing-3 satellite over San Francisco Bay area showed the small craft could take clear hi-res images while moving.
In just 42 seconds, a small Chinese satellite captured images of a large area around a US city that would be sharp enough to identify a military vehicle on the street and tell what type of weapon it might be carrying, say scientists reporting on the breakthrough.


Comment: And that's at least one message that this release is intended to convey.


Beijing-3, a small one-tonne commercial satellite launched by China in June performed an in-depth scan of the core area of the San Francisco Bay (3,800 square kilometres or 1,470 square miles), according to scientists involved in the project.

Most Earth observation satellites must be stable when taking images because attitude control mechanisms can produce vibrations that blur the images. But in this experiment on June 16, the Beijing-3 rolled and yawed wildly, the dramatic motion changing the angle of its camera's line of sight to the ground when flying over North America. The movement allowed it to capture a larger area than satellites have managed until now.

Comment: The US is doing everything it can to prevent China, and Russia, from entering markets, with some countries, such as Germany, sabotaging their own economies to appease them, however these tactics won't work forever: Also check out SOTT radio's: NewsReal: Why You Should Question Media Reports About China 'Causing Covid' And 'Invading Taiwan'