Dev.SN

janrinok writes:

of all the fishes in the sea the mermaid is the one for me.

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"martyb" writes:

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janrinok writes:

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Arthur T Knackerbracket has processed the following story:

Arthropods belong to an evolutionary branch – the ecdysozoa – that contains about half of all animal species, and the earliest fossil evidence of the group now dates back 550 million years

21 November 2024

3D laser scan of the specimen, Uncus dzaugisi

Mary L. Droser

A worm-like creature preserved in ancient rock has just been identified as the oldest known relative of insects, spiders and crustaceans.

The ecdysozoans are a group of invertebrate animals with a tough outer coating, or cuticle, that they moult as they grow. It is clearly a successful evolutionary strategy, because today the group contains millions of species. “Some estimates suggest that about half of all known animal species are ecdysozoans,” says Ian Hughes at Harvard University. All arthropods – including insects and spiders – belong to the group, and so do …

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Arthur T Knackerbracket has found the following story:

In the absence of biological catalysts and metabolism, can atmospheric and geochemical processes provide the substrates and conditions required for production of biological molecules? Becker et al. devised an abiotic synthetic scheme that allows for accumulation of both purine and pyrimidine nucleoside mono- and diphosphates (see the Perspective by Hud and Fialho). A key starting material for this chemistry, hydroxylamine and/or hydroxylamine disulfonate, can form under plausible early atmospheric conditions. Cycles between wet and dry conditions provide the environments necessary to complete formation of purine and pyrimidine bases essentially in one pot.

Theories about the origin of life require chemical pathways that allow formation of life’s key building blocks under prebiotically plausible conditions. Complex molecules like RNA must have originated from small molecules whose reactivity was guided by physico-chemical processes. RNA is constructed from purine and pyrimidine nucleosides, both of which are required for accurate information transfer, and thus Darwinian evolution. Separate pathways to purines and pyrimidines have been reported, but their concurrent syntheses remain a challenge. We report the synthesis of the pyrimidine nucleosides from small molecules and ribose, driven solely by wet-dry cycles. In the presence of phosphate-containing minerals, 5′-mono- and diphosphates also form selectively in one-pot reactions. The pathway is compatible with purine synthesis, allowing the concurrent formation of all Watson-Crick bases.

Original Submission

"martyb" writes:

Liliputing:

Windows 10X is Microsoft's new operating system designed for dual-screen and foldable devices, although it also has some features that could make it an interesting new option for traditional tablets and laptops.

While the operating system is still a work in progress, this week Microsoft released a set of Windows 10X development tools including a Windows 10X emulator. And in practically no time flat, folks started figuring out how to install Windows 10X on hardware that it's not supposed to run on.

If you want to play along at home, there's a set of instructions — but I'd suggest reading them all before getting started and then proceeding with caution if you still want to proceed at all.

Original Submission

SNAPI_Test writes:

Title: Unified Prebiotically Plausible Synthesis Of Pyrimidine And Purine Rna Ribonucleotides

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Arthur T Knackerbracket has found the following story:

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In the absence of biological catalysts and metabolism, can atmospheric and geochemical processes provide the substrates and conditions required for production of biological molecules? Becker et al. devised an abiotic synthetic scheme that allows for accumulation of both purine and pyrimidine nucleoside mono- and diphosphates (see the Perspective by Hud and Fialho). A key starting material for this chemistry, hydroxylamine and/or hydroxylamine disulfonate, can form under plausible early atmospheric conditions. Cycles between wet and dry conditions provide the environments necessary to complete formation of purine and pyrimidine bases essentially in one pot.

Theories about the origin of life require chemical pathways that allow formation of life’s key building blocks under prebiotically plausible conditions. Complex molecules like RNA must have originated from small molecules whose reactivity was guided by physico-chemical processes. RNA is constructed from purine and pyrimidine nucleosides, both of which are required for accurate information transfer, and thus Darwinian evolution. Separate pathways to purines and pyrimidines have been reported, but their concurrent syntheses remain a challenge. We report the synthesis of the pyrimidine nucleosides from small molecules and ribose, driven solely by wet-dry cycles. In the presence of phosphate-containing minerals, 5′-mono- and diphosphates also form selectively in one-pot reactions. The pathway is compatible with purine synthesis, allowing the concurrent formation of all Watson-Crick bases.

This is an article distributed under the terms of the Science Journals Default License.

Vol 366, Issue 6461
04 October 2019

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By Sidney Becker, Jonas Feldmann, Stefan Wiedemann, Hidenori Okamura, Christina Schneider, Katharina Iwan, Antony Crisp, Martin Rossa, Tynchtyk Amatov, Thomas Carell

Concurrent synthesis of complementary ribonucleotides from geochemical precursors can proceed via wet and dry cycles.

By Sidney Becker, Jonas Feldmann, Stefan Wiedemann, Hidenori Okamura, Christina Schneider, Katharina Iwan, Antony Crisp, Martin Rossa, Tynchtyk Amatov, Thomas Carell

Concurrent synthesis of complementary ribonucleotides from geochemical precursors can proceed via wet and dry cycles.

Vol 366, Issue 6461

© 2019 American Association for the Advancement of Science. All rights reserved. AAAS is a partner of HINARI, AGORA, OARE, CHORUS, CLOCKSS, CrossRef and COUNTER.
Science ISSN 1095-9203.

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SNAPI_Test notes that Arthur T Knackerbracket has found the following story:

The United States, Britain and Australia have called on Facebook to give authorities the ability to circumvent encryption used in its messaging services—a measure opposed by the social media giant.

Facebook has been dogged by several privacy scandals in recent years and has pledged to boost user protections by rolling out end-to-end encryption across all of its social media platforms.

But that plan risks weakening the ability of law enforcement to detect criminal acts including terrorism and child pornography, according to a joint letter signed by US Attorney General William Barr, British Home Secretary Priti Patel and Australian Home Affairs Minister Peter Dutton.

"Facebook has not committed to address our serious concerns about the impact its proposals could have on protecting our most vulnerable citizens," said the Thursday letter, addressed to company chief Mark Zuckerberg and seen by AFP.

The company already encrypts WhatsApp messages from end-to-end—meaning only the sender and recipient can read the message—and is working to extend the technology to other apps in its family, including Messenger and Instagram.

Facebook says it is intent on introducing the service without granting oversight to law enforcement agencies.

"We strongly oppose government attempts to build backdoors because they would undermine the privacy and security of people everywhere," a Facebook spokesperson said.

[...] During a livestreamed question and answer session with employees, Zuckerberg said Facebook would continue to work with authorities to strike a balance between privacy concerns and fighting crimes such as child exploitation and terrorism.

"Having the availability to look at the content is a useful signal, and when you lose that you are fighting that battle with at least a hand tied behind your back and you hope there is a lot of good stuff you can do with your other hand," Zuckerberg said.

But he added that encryption had many positive benefits such as protection for journalists and political protesters.

SNAPI_Test writes:

Arthur T Knackerbracket has found the following story:

Andromeda, a massive spiral galaxy, has swallowed several galaxies within the last few billion years before setting its sights on the Milky Way.

"The Milky Way is on a collision course with Andromeda in about four billion years,” said Dougal Mackey, co-author of a new study published in Nature and a research fellow at the Australian National University. “So knowing what kind of a monster our galaxy is up against is useful in finding out the Milky Way's ultimate fate."

The astronomers noted that the stellar halo that surrounds Andromeda is much bigger and more complex than the Milky Way, and it contains two giant globular clusters of stars that are rotating perpendicular to each other, and this indicates that it has cannibalized other galaxies in the past. They made observations using the wide-field camera on the Canada-France-Hawaii-Telescope, and this showed that the globular clusters are on the same rotation axis as a plane of dwarf galaxies that orbit Andromeda.

Andromeda is a good specimen to study the evolution of spiral galaxies like the Milky Way, Mackey explained. "One of our main motivations in studying astronomy is to understand our place in the Universe. A way of learning about our galaxy is to study others that are similar to it, and try to understand how these systems formed and evolved.”

"Sometimes this can actually be easier than looking at the Milky Way, because we live inside it and that can make certain types of observations quite difficult."

Reference:

Mackey, D., Lewis, G.F., Brewer, B.J. et al. Two major accretion epochs in M31 from two distinct populations of globular clusters. Nature 574, 69–71 (2019).

DOI: 10.1038/s41586-019-1597-1

SNAPI_Test writes:

Arthur T Knackerbracket has found the following story:

Unpredictable weather in Europe has produced some of the lowest honey harvests ever, particularly in France and Italy. Only about half the normal harvest was collected in Italy and only about a quarter of the usual crop in France. Even recent high honey producing countries such as Romania and Spain are seeing decreases. The reasons for the declines are varied and include frosts, droughts, and heavy rains across the affected countries, but everyone is counting on better weather conditions in the coming year. However, even if that pans out, recovery will be challenging.

To save the colonies, "the bees have killed all the males to get rid of extra mouths to feed". The lack of males for mating may lead to a "lack of fertilized queens" next spring, meaning fewer new colonies and bees.

Bee mortality has also shot up in recent years due to an "epidemic" of the Varroa parasitic mite, the uncontrolled spread of the Asian hornet in Europe, and the "intense use of pesticides in agriculture", according to the French Cyclops report.

Beekeepers are also complaining about a massive influx of low-cost Chinese honey, which they say is "adulterated," such as being cut with sugar syrup.

There is currently no European legislation requiring producers to specify the origin of honey.

Labels can state it is a "blend of honeys originating and non-originating in the European Community", even if the product contains 99 percent Chinese honey and only 1 percent of, say French honey.

In Spain, beekeepers have held several protests against low-cost Chinese honey and authorities are planning to impose new labelling requirements which would list the percentages of honey included per country of origin.

In France, a decree is expected to come into force on January 1, 2020 which would list all countries that have supplied more than 20 percent of the honey in a jar, in order of importance.

hubie writes:

The Hopewell civilization refers to a culture shared by native Americans tribes from about 200 BC to 400 AD that spanned a region from the eastern coast to the Rocky Mountains, and from the Great Lakes to the Gulf of Mexico. The fairly rapid decline of this culture has been a mystery for many years. A group of researchers from the University of Cincinnati found evidence of a Tunguska-like airburst that struck sometime between 252 and 383 AD and affected an area of 9200 square miles (24,000 sq km). That time range coincides with a period when 69 near-Earth comets were observed and documented by Chinese astronomers, and many Native American tribes include some sort of devastating event from the skies in their oral histories.