O nouă abordare în lupta împotriva cancerului

Un mecanism celular străvechi, de la începuturile evoluției, s-ar putea să ne aducă noi tratamente, infailibile, împotriva cancerului.

Exciting new research from Northwestern Medicine has discovered that inside every cell within the human body is a toxic kill code designed to trigger self-destruction if it senses a cell is turning cancerous. Across two newly published studies the scientists remarkably homed in on the exact nucleotide code underlying this mechanism and suggest it may lead to an entirely novel kind of cancer treatment.

Sursa: Cellular kill code discovery may help extinguish cancers | New Atlas

Un specialist în poezia Egiptului Antic a descoperit cum au fost ridicate piramidele

Da, recunosc, titlul e un pic înșelător. Arheologul din poveste nu a lucrat de capul lui, ci în cadrul unei echipe internaționale de cercetători britanici și francezi. Dar descoperirea lor rămâne remarcabilă.

Pe scurt: rampe și scripeți. Cu vreo 2000 de ani înainte de precedentele atestări ale scripeților din Grecia Antică.

What began as an expedition to record the inscriptions of ancient Egyptian quarry workers produced a remarkable discovery about the Great Pyramid at Giza. My colleagues and I in the Anglo-French joint archaeological mission to the ancient quarry site of Hatnub recently revealed the existence of a well-preserved haulage ramp dating to the time of the Great Pyramid, roughly 4,500 years ago.

We think this could significantly change the theories about how the workers who built the monument were able to transport such large blocks of stone to great heights. It could even provide evidence that pulleys were invented hundreds of years earlier than previously documented.

The rock-cut ramp is flanked by two flights of rock-cut stairs, into which are cut post holes that would originally have held wooden posts, now long perished. The pattern of post holes is well enough preserved that we can begin to reconstruct a pulley system that would have been used to lift large blocks of alabaster out of the open-cast quarry.

[…]

Ancient graffiti

These discoveries have emerged from the work of the University of Liverpool’s joint expedition with the French Institute for Oriental Archaeology in Cairo to Hatnub, which is some 20km from the Nile in the eastern desert of Middle Egypt. This quarry was the most prestigious ancient source of Egyptian alabaster, the milky white banded translucent stone that was used by the Egyptians to make vessels, statues, and architectural items.

Our original aim was purely to record the surviving inscriptions left by quarrymen 4,500 to 4,000 years ago. I began my career studying Egyptian poetry, but it turns out quarrymen could on occasion get quite poetic when writing their graffiti in the quarry. And so I now study these texts, written in a cursive version of the Egyptian script known as hieratic.

We have so far identified more than 100 previously unrecorded texts, offering a wealth of information about the organisation and logistics of the expeditions that came to the quarry to extract alabaster.

[…]

Our ultimate goal is to study all aspects of stone extraction and transport at Hatnub, integrating the rich textual and archaeological evidence to provide a more holistic understanding of quarrying in ancient Egypt. Few sites offer the range and diversity of evidence that survives at Hatnub. We have many years of work ahead of us; the potential for further exciting discoveries is huge.

Sursa: Great Pyramid: how my research on ancient Egyptian poetry led to an amazing discovery | The Conversation

Foto: Roland Enmarch, Universitatea din Liverpool

O altfel de cursă spațială

Nu vă mai uitați la rivalitatea dintre SUA, Europa, China și Rusia. Nici măcar la întrecerea dintre SpaceX și Blue Origin, noua cursă spațială privește rachetele mici, care pot pune pe orbita Pământului, mai des de o dată pe lună, micro și nanosateliți cu mase de ordinul kilogramelor sau zecilor de kilograme, pentru tot felul de aplicații.

In mid-November, a company called Rocket Lab will try to send six small satellites into orbit around Earth—a fairly banal undertaking, save for the size of the launch rocket.

Sursa: Small rockets are taking off | PHYSorg.com: Space & Earth News

Foto: racheta Electron în timpul unor teste, Rocket Lab.

Adio, Kepler

Telescopul spațial Kepler, specializat pe identificarea planetelor din afara sistemului nostru solar, a rămas într-un final fără combustibil și și-a încheiat activitatea.

În urma misiunii sale de numai 9 ani rămâne o moștenire de 354 exoplanete confirmate și peste 2900 de candidate, precum și fascinanta concluzie conform căreia 70% dintre stelele de mărimea Soarelui din galaxia noastră găzduiesc planete solide în zona locuibilă.

— Mai multe detalii pe Space.com

Foto: NASA/Wendy Stenzel/Daniel Rutter

Uraniul va fi extras din apa mării?

Americanii au pus la punct un procedeu economic de extragere a uraniului din apa mării. Conform calculelor lor, în oceane am avea destul uraniu cât să alimentăm o mie de centrale pe fisiune cu capacitatea de 1 GW timp de 100.000 de ani. La un preț comparabil cu cel al mineritului convențional. Practic, în testul lor, 1 kg de fibre acrilice special tratate au extras într-o lună 5 grame de uraniu. Pare puțin, dar procedeul suportă o scalare oricât de mare. O tonă de fibre ar produce 5 kg pe lună, 1000 de tone de fibre – 5 tone de uraniu etc.

Along with salt, a liter of seawater also contains sulfates, magnesium, potassium, bromide, fluoride, gold, and uranium. There isn’t much of the latter – something like 3 micrograms per liter (0.00000045 ounces per gallon), but when you consider how big the ocean is, that works out to 500 times more uranium in the sea than could be mined on land – that’s 4 billion tons, or enough to run a thousand 1-gigawatt fission reactors for 100,000 years.

— Citește mai multe detalii pe New Atlas

Odă Modelului Standard

E sâmbătă. Ce zi ar putea fi mai potrivită pentru o scurtă recapitulare a fundamentelor mecanicii cuantice? E o poveste fără formule, vă promit.

The Standard Model. What dull name for the most accurate scientific theory known to human beings. […] Yet its name suggests that if you can afford a few extra dollars a month you should buy the upgrade. As a theoretical physicist, I’d prefer The Absolutely Amazing Theory of Almost Everything. That’s what the Standard Model really is.

Glenn Starkman, Distinguished University Professor of Physics, Case Western Reserve University

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