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Microscope 1

First animal without mitochondria and that doesn't breathe discovered

Brandon Specktor
Live Science
Tue, 25 Feb 2020 20:39 UTC
salminicola
© Stephen Douglas Atkinson
Spores of the parasite H. salminicola swim under a microscope. Those alien "eyes" are actually stinger cells, one of the few features this organism hasn't evolved away.
When the parasitic blob known as Henneguya salminicola sinks its spores into the flesh of a tasty fish, it does not hold its breath. That's because H. salminicola is the only known animal on Earth that does not breathe.

If you spent your entire life infecting the dense muscle tissues of fish and underwater worms, like H. salminicola does, you probably wouldn't have much opportunity to turn oxygen into energy, either. However, all other multicellular animals on Earth whose DNA scientists have had a chance to sequence have some respiratory genes. According to a new study published today (Feb. 24) in the journal Proceedings of the National Academy of Sciences, H. salminicola's genome does not.

A microscopic and genomic analysis of the creature revealed that, unlike all other known animals, H. salminicola has no mitochondrial genome — the small but crucial portion of DNA stored in an animal's mitochondria that includes genes responsible for respiration.

Comment: See also: And check out SOTT radio's: The Truth Perspective: Are Cells the Intelligent Designers? Why Creationists and Darwinists Are Both Wrong

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Easter Egg 2

Choosy eggs may pick sperm for their genes, defying Mendel's law

Carrie Arnold
Quanta Magazine
Wed, 15 Nov 2017 07:43 UTC
sperm selection
© Allison Filice for Quanta Magazine
In the winner-takes-all game of fertilization, millions of sperm race toward the egg that's waiting at the finish line. Plenty of sperm don't even make it off the starting line, thanks to missing or deformed tails and other defects. Still others lack the energy to finish the long journey through the female reproductive tract, or they get snared in sticky fluid meant to impede all but the strongest swimmers. For the subset of a subset of spermatozoa that reach their trophy, the final winner would be determined by one last sprint to the end. The exact identity of the sperm was random, and the egg waited passively until the Michael Phelps of gametes finally arrived. Or so scientists have thought.

Joe Nadeau, principal scientist at the Pacific Northwest Research Institute, is challenging this dogma. Random fertilization should lead to specific ratios of gene combinations in offspring, but Nadeau has found two examples just from his own lab that indicate fertilization can be far from random: Certain pairings of gamete genes are much more likely than others. After ruling out obvious alternative explanations, he could only conclude that fertilization wasn't random at all.

"It's the gamete equivalent of choosing a partner," Nadeau said.

His hypothesis - that the egg could woo sperm with specific genes and vice versa - is part of a growing realization in biology that the egg is not the submissive, docile cell that scientists long thought it was. Instead, researchers now see the egg as an equal and active player in reproduction, adding layers of evolutionary control and selection to one of the most important processes in life.

Comment: If true that the egg 'chooses' or selects for the best genetic package, then the idea that random mutations lead to evolution (which already has a probability so low that it can be said to be impossible) is even less likely to happen.

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Galaxy

Mysterious dimming star Betelgeuse brightens again, dashes hopes of imminent premature death

Svetlana Ekimenko
Sputnik International
Mon, 24 Feb 2020 11:13 UTC
This artists impression shows the supergiant star Betelgeuse
© ESO
This artists impression shows the supergiant star Betelgeuse as it would be if it were in the solar system - its outer edge would go as far out as Jupiter, swallowing the inner planets
At the end of 2019, Betelgeuse generated a great deal of excitement among astronomers, who had noticed the red giant, known to get dimmer and brighter, had begun to do so on an unprecedented scale, with many starting to hope for a looming supernova.

According to the latest round of observations, the notorious star Betelgeuse has ceased to manifest the dimming effect that many had hoped was a sure sign of a looming supernova effect, and is reported to actually be brightening.

"Photometry secured over the last ~2 weeks shows that Betelgeuse has stopped its large decline of delta-V of ~1.0 mag relative to September 2019," astronomers wrote in an Astronomers Telegram.
"Based on these and additional observations, Betelgeuse has definitely stopped dimming and has started to slowly brighten. Thus this 'fainting' episode is over but additional photometry is needed to define the brightening phase," added the scientists in their report entitled "The Fall and Rise in Brightness of Betelgeuse".
While the newest data signifies the celestial body is not about to explode in a premature death, this still leaves open the question as to why it had started dimming in the first place.

"Observations of all kinds continue to be needed to understand the nature of this unprecedented dimming episode and what this surprising star will do next," the astronomers wrote.

Comment: Light from Betelgeuse faintest ever recorded, temperature way down in just 4 months, yet star has 'swollen' by 9%

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Seismograph

Mars is seismically active, NASA's InSight lander reveals

Mike Wall
Space.com
Mon, 24 Feb 2020 22:52 UTC
Mars lander
© NASA/JPL-Caltech
This image, the second selfie captured by NASA's InSight Mars lander, is a mosaic of 14 photos taken between March 15 and April 11, 2019.
Mars may be cold and dry, but it's far from dead.

The first official science results from NASA's quake-hunting InSight Mars lander just came out, and they reveal a regularly roiled world.

"We've finally, for the first time, established that Mars is a seismically active planet," InSight principal investigator Bruce Banerdt, of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, said during a teleconference with reporters Thursday (Feb. 20).

Martian seismicity falls between that of the moon and that of Earth, Banerdt added.

"In fact, it's probably close to the kind of seismic activity you would expect to find away from the [tectonic] plate boundaries on Earth and away from highly deformed areas," he said.

Comment: See also:

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Telescope

Scientists eye the Martian underground in search for alien life

Leonard David
Space.com
Thu, 20 Feb 2020 22:34 UTC
mars caves
© USGS
The U.S. Geological Survey's (USGS) Astrogeology Science Center has released the locations of more than 1,000 cave-entrance candidates on Mars. The dots indicate the location of possible caves in the Tharsis region on Mars
The search for present-day life on Mars is heating up. And for good reason: An improved knowledge of Mars' geologic diversity and history, a better appreciation of life in extreme environments here on Earth, and a sharp focus on sensitive life-detection measurement methods are all bolstering the Mars-life hunt, giving scientists more reason to think that they just might find something.

Still, the issue of life on Mars demands new scientific concepts and knowledge concerning where to explore on the Red Planet and what to measure.

Astrobiologists and other experts tackled some of these issues last November during a conference at the National Cave and Karst Research Institute in Carlsbad, New Mexico.

On the meeting agenda was a discussion of how best to test for extant life on Mars, with or without the benefit of collection systems. Such systems include a complex and pricey Mars sample-return effort that officially kicks off this summer with the launch of NASA's Mars 2020 rover.
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Tornado2

Scientists are using nuclear weapons surveillance tech to 'hear' tornadoes

Maddie Stone
The Roanoak Times
Sun, 23 Feb 2020 00:00 UTC
tornado
© Associated Press | File 2008
A large tornado touches down in Orchard, Iowa, in 2008. Scientists are putting the same sound technology they use to detect nuclear weapons testing to better forecast tornadoes.
Technology developed to detect nuclear weapons detonations from afar might help meteorologists track tornadoes.

A team of scientists is hoping to enhance tornado detection with some help from an unlikely source — specialized microphones developed to assist governments in spotting illegal nuclear weapons tests.

Tornadoes are one of the most challenging extreme weather events for forecasters to predict and warn against. Often too small to leave a clear, unequivocal signature on radar, human eyeballs remain one of our primary tools for confirming these violent vortices.

But Roger Waxler of the University of Mississippi's National Center for Physical Acoustics believes tornadoes may be more trackable from a distance by listening to them.

Waxler's team, which previously developed a state-of-the-art microphone for picking up infrasound, or sound below the range of human hearing, presented evidence at the American Meteorological Society meeting in Boston last month that tornadoes emit infrasonic signals that can be heard over 50 miles away.
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Eye 1

Small eye movements are critical for 20/20 vision says new study


University of Rochester
Mon, 10 Feb 2020 18:14 UTC
Eye Chart
© Getty Images
When a patient fails an eye test, it's not just structural defects in the eye that are to blame. New Rochester research show that small eye movements humans aren’t even aware of making play a large role in humans’ ability to see letters, numbers, and objects from a distance.
Visual acuity — the ability to discern letters, numbers, and objects from a distance — is essential for many tasks, from recognizing a friend across a room to driving a car.

Researchers previously assumed that visual acuity was primarily determined by the optics of the eye and the anatomy of the retina. Now, researchers from the University of Rochester — including Michele Rucci, a professor of brain and cognitive sciences, and Janis Intoy, a neuroscience graduate student at Boston University and a research assistant in Rucci's lab in Rochester — show that small eye movements humans aren't even aware of making play a large role in humans' visual acuity. The research, published in the journal Nature Communications, may lead to improved treatments and therapies for vision impairments.

Unlike a stationary camera that takes a fixed photograph of the world, human eyes are constantly moving, taking in new pieces of a visual scene and continually changing the visual input to the retina.

"Humans are normally not aware that their eyes are always in motion, even when attempting to maintain a steady gaze on a point," Intoy says.

These gaze shifts, known as fixational eye movements, were once thought to be inconsequential because they are so small. But, they are large on a microscopic level, relative to the size of cells in the retina, and they shift the image across many receptors. Rucci and the members of his lab have progressively shown that these movements are critical to processes in the visual system.
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Info

Origins of immune system mapped


Wellcome Sanger Institute
Thu, 20 Feb 2020 05:10 UTC
Human Thymus
© Kenny Roberts, Bayraktar lab, Wellcome Sanger Institute
Section of a developing human thymus. The scale bar represents 1mm.
A first cell atlas of the human thymus gland could lead to new immune therapies to treat cancer and autoimmune diseases. Researchers from the Wellcome Sanger Institute, Newcastle University and Ghent University, Belgium, mapped thymus tissue through the human lifespan to understand how it develops and makes vital immune cells called T cells. In the future, this information could help researchers to generate an artificial thymus and engineer improved therapeutic T cells.

Published today in Science, this human thymus atlas has revealed new cell types and identified signals that tell immature immune cells how to develop into T cells. The atlas could also help scientists understand diseases that affect T cell development such as severe combined immunodeficiency (SCID), and adds to the Human Cell Atlas initiative which is creating a Google map of the entire human body.

The thymus gland is located in the chest and produces T cells, key white blood cells that fight infection and disease. These T cells then leave the thymus to enter the blood and other parts of the body to mature further. T cells seek out and destroy invading bacteria and viruses, and also recognise cancer cells and kill them.

Problems in thymus development causes defective T cell generation. This can result in severe immune deficiencies such as SCID, leaving people susceptible to infections. Alternatively, it can affect T cell regulation resulting in autoimmune diseases such as Type 1 diabetes. While mature T cells have been well studied, the development of the human thymus and T cells within it is not fully understood.
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Galaxy

Reviewing Brian Greene's new book 'Until the End of Time': Big vision, but only shows the pitfalls of reductive materialism

Philip Ball
Nature
Sun, 23 Feb 2020 22:03 UTC
gas dust nebula interstellar
© M. Livio and the Hubble Team (STScI)/NASA/ESA
A cloud of interstellar gas and dust, captured by NASA’s Hubble Space Telescope.
Brian Greene's Until the End of Time sits within a tradition of grand, synoptic visions of the Universe, rooted in physics, that feels (to this British reader) distinctively American. Halfway through, I realized why. With its scepticism of religion but openness to humanistic wonder, awe of nature, celebration of the individual and recognition of the power of physical law, the narrative has a strong whiff of transcendentalism. There is an echo of philosopher Henry David Thoreau in Greene's account of lying out at night, enraptured by the aurora borealis. And essayist Ralph Waldo Emerson's declaration that the "sublime laws play indifferently through atoms and galaxies" could almost be this book's epigraph.


Comment: In other words, it's secular religion - which sits uncomfortably in the chair of hardcore materialism the modern scientific community demands of it.


Such qualities lift this work above many accounts of the cosmic story spanning from the Big Bang to the end of time — whether that's a big rip, heat death or cosmic bounce. Greene takes us from quarks to consciousness, and from the origin of life to the genesis of language. He draws from an impressive range of sources, such as poets William Butler Yeats and Sylvia Plath. In attempting to weave in the evolution of physical laws with that of the human mind and cultures, Greene's aim vaults beyond that of his bestselling 1999 book, The Elegant Universe. Until the End of Time is packed with ideas; whether they come together as a convincing story is another matter.

This narrative features humanity as a brief moment when matter became self-aware. Current physical and cosmological theories imply that this state of affairs can't last. Eventually proton decay, a dominance of dark energy or thermodynamic heat death will doom all matter and thought. Greene, however, suggests that intelligent beings could eke out their thought processes almost indefinitely by gradually slowing them to minimize their inevitable thermodynamic cost.
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Seismograph

How earthquakes deform gravity

Helmholtz Association of German Research Centres
Phys.org
Fri, 21 Feb 2020 12:00 UTC
Tohoku
© Earth and Planetary Science Letters, Vol 536, Zhang et al. 2020, „Prompt elasto-gravity signals (PEGS) and their potential use in modern seismology",sciencedirect.com/journal/earth-and-planetary-science-letters, with permission from Elsevier
Spatial distribution of PEGS signal strength during the Tohoku quake in 2011, shortly before the arrival of the primary seismic wave.
Lightning — one, two, three — and thunder. For centuries, people have estimated the distance of a thunderstorm from the time between lightning and thunder. The greater the time gap between the two signals, the further away the observer is from the location of the lightning. This is because lightning propagates at the speed of light with almost no time delay, while thunder propagates at the much slower speed of sound of around 340 metres per second.

Earthquakes also send out signals that propagate at the speed of light (300,000 kilometers per second) and can be recorded long before the relatively slow seismic waves (about 8 kilometers per second). However, the signals that travel at the speed of light are not lightning bolts, but sudden changes in gravity caused by a shift in the earth's internal mass. Only recently, these so-called PEGS signals (PEGS = prompt elasto-gravity signals) were detected by seismic measurements. With the help of these signals, it might be possible to detect an earthquake very early before the arrival of the destructive earthquake or tsunami waves.

Comment: See also: And check out SOTT radio's: Behind the Headlines: Earth changes in an electric universe: Is climate change really man-made?

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