New Giant Viruses Further Blur the Definition of Life


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For decades, descriptions of viruses have straddled life and nonlife, a divide that usually isn’t difficult to navigate. Their hallmark characteristics, namely their small size, tiny genomes and parasitic dependence on cellular hosts for replication, set them apart from all other living things despite their animation. But that story has gotten far more puzzling — particularly since the discovery of the first giant virus in 2003, which was so large that researchers initially thought it was a bacterium.

Several families of giant viruses are now known, and some of those giants have more than 1,000 genes; one has a whopping 2,500. (By comparison, some small viruses have only four genes.)

The complete article

Jordana Cepelewicz — Quanta

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The Almost-Proof of Fermat’s Last Theorem


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Fermat’s Theorem continues to remain one of the biggest open problems in Mathematics. The needull discusses one big flaw in all the proposed solutions to the theorem.

Except there was a catch. As my story “New Number Systems Seek Their Lost Primes” describes, by expanding the number system to include new values, mathematicians lost something essential: unique prime factorization. Primes are the atoms of a number system — its fundamental building blocks — and unique prime factorization ensures that any number, such as 12, can be expressed uniquely as a product of primes: 2 x 2 x 3. The expanded number systems used to solve Fermat’s Last Theorem yielded competing prime factorizations, making these systems an ultimately shaky basis on which to construct a proof.

“Even today, in many false proofs of Fermat’s Last Theorem found by amateurs, somewhere or other this is the mistake — they’re assuming in some of these bigger number systems that numbers can be uniquely decomposed into primes,” said Manjul Bhargava, a mathematician at Princeton University. “It’s so counterintuitive to think that could fail for a bigger number system, but it sometimes does.”

The complete article

Kevin Hartnett – Quanta

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The Strange Case of Typhoid Mary


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This needull tries to drive home a very important point – we need to understand tolerance of human body against disease causing germs. Defense is as equal an important strategy as offence when fighting.

 In the early 1900s, an Irish cook named Mary Mallon made the rounds in New York City, cooking for various wealthy families. She left a wave of infection in her wake. Scientists eventually discovered that she was a healthy carrier of typhoid fever, meaning that she carried the bacteria that causes typhoid but showed no outward symptoms. Mallon became immortalized as Typhoid Mary, a nickname that came to symbolize the spread of disease. “Typhoid Mary was a very tolerant host who unfortunately also shed tons of pathogen,” said David Schneider, an immunologist at Stanford University.

The complete article

Quanta Magazine — Emily Singer

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Three Puzzles Inspired by Ramanujan


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Today’s needull is a very neat article. The writer gives you three puzzles to solve. When you finally look at the solution, they don’t look very difficult. So, for people out there wanting to exercise their grey cells, this one is for you.

The mathematician Mark Kac divided all geniuses into two types: “ordinary” geniuses, who make you feel that you could have done what they did if you were say, a hundred times smarter, and “magical geniuses,” the working of whose minds is, for all intents and purposes, incomprehensible. There is no doubt that Srinivas Ramanujan was a magical genius, one of the greatest of all time. Just looking at any of his almost 4,000 original results can inspire a feeling of bewilderment and awe even in professional mathematicians: What kind of mind can dream up exotic gems like these?

The complete article

Quanta Magazine — Pradeep Mutalik

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