Tag

Pnas

All articles tagged with #pnas

science1 month ago•3 min saved

New Study Suggests Evolution Drifts Toward Robustness, Not Randomness

Researchers from the Technion Israel Institute of Technology have published a study in PNAS challenging the traditional view that evolution proceeds randomly when multiple traits offer equal fitness. Using mathematical models, they demonstrate that populations exhibit 'directional drift,' moving toward flatter regions of the fitness landscape where traits are more resistant to mutations, thereby increasing long-term resilience without direct selective pressure.

via ScienceAlert|

#evolutionary-biology #fitness-landscapes #genetics

science4 months ago•12 min saved

Ants: 20 Quadrillion Individuals, Biomass Roughly One-Fifth of Humans and Larger Than Birds and Mammals

A 2022 PNAS-derived estimate puts Earth's ant population at about 20 quadrillion (2×10¹⁶), yielding roughly 12 megatons of dry carbon in biomass (about 24 Mt total when including other elements), or about one-fifth of human biomass. Even with this conservative figure, ants outweigh the combined biomass of all wild birds and wild mammals and underscore their outsized ecological role, while providing a global baseline for future insect abundance and biodiversity research.

via Space Daily|

#ants #biomass #ecology

science5 months ago•31 min saved

Trinity Glass Yields First-Ever Clathrate Crystal

Scientists using CT and X-ray scans on trinitite—the glass formed by the 1945 Trinity nuclear test—have identified a hitherto unseen red clathrate crystal trapped within its lattice. This marks the first observation of such a clathrate in natural or nuclear-explosion materials, highlighting the extreme conditions produced by nuclear detonations; researchers caution that collecting samples from the blast site is illegal.

via Yahoo News New Zealand|

#clathrate #luca-bindi #pnas

technology5 months ago•5 min saved

When AI Evolves: Could Machines Rewrite Evolution Itself?

A new PNAS paper argues we may be entering an era of evolvable AI—AI systems that can replicate and vary, potentially guiding their own evolution. It outlines two scenarios: an ecosystem where AI variants compete with little oversight, and a breeder scenario where human-directed selection tames evolution. The authors also suggest AI could bypass traditional mutation limitations via horizontal information transfer and self-directed variation, even leveraging existing code from the internet. While ongoing human control could mitigate risks, unchecked evolvable AI might still escape or drive a major evolutionary shift, possibly through human–machine symbiosis rather than a direct biological transition.

via The Conversation|

#artificial-intelligence #evolution #evolvable-ai

science7 months ago•7 min saved

AI Uncovers 303 New Nazca Geoglyphs, Fast-Tracking Archaeology

An AI-assisted survey of Peru’s Nazca Desert dramatically accelerates archaeology by identifying 303 new figurative geoglyphs and 42 geometric designs (bringing the total to 683) after screening 47,410 candidate patches and validating 1,309 sites through drone and on-ground checks. Led by Masato Sakai with IBM Research, the findings reveal relief-style figures (humans, decapitated heads, camelids) nearby trails and line-type figures (birds, whales) along formal routes, while suggesting about 1,000 more high-potential sites await verification, marking roughly a sixteen-fold jump in discovery rate and shifting fieldwork toward targeted surveying.

via Indian Defence Review|

#ai-archaeology #geoglyphs #masato-sakai

science7 months ago•8 min saved

AI Uncovers New Physics in Dusty Plasmas, Redefining Inter-Particle Forces

Physicists at Emory used a physics-tailored neural network trained on 3D dusty-plasma data to reveal precise, non-reciprocal inter-particle forces, correct key theoretical assumptions, and propose a universal AI-based framework for inferring physical laws in complex many-body systems.

via SciTechDaily|

#dusty-plasma #machine-learning #many-body-systems

science8 months ago•22 min saved

Medico’s Mouse‑Only “Cure” Sparks Hype and Scrutiny Over Pancreatic Cancer Trial

Spanish biochemist Mariano Barbacid announced a “cure” for pancreatic cancer based on a triple‑drug therapy that regression‑tested 45 mice; the work, published in PNAS after Nature declined to publish, has not been tested in humans or metastases. The flashy public rollout and patent push by Barbacid’s Vega Oncotargets drew patient inquiries and criticism from CNIO colleagues for overclaiming and conflicts of interest. Independent experts urge cautious optimism, noting the (promising but early) preclinical results and emphasizing that mouse outcomes rarely translate to human cures, with human trials years away and more work needed on safety and efficacy.

via EL PAÍS English|

#barbacid #kras #pancreatic-cancer

science-and-technology1 year ago•1 min saved

Rising Tide of Scientific Fraud: Organized Networks and Escalating Fake Publications

A study published in PNAS reveals that scientific fraud is increasing rapidly, doubling every 1.5 years since 2010, posing a serious threat to the integrity of scientific research.

via The Economist|

#peer-review #pnas #research-integrity

science2 years ago•7 min saved

Unveiling the Mystery of Life's Origin: Decoding Early Earth's RNA Puzzle

Leading origin-of-life researcher Gerald Joyce's recent paper in PNAS, "RNA-catalyzed evolution of catalytic RNA," has been lauded as a breakthrough in understanding life's origin through natural processes. However, critics argue that the results only demonstrate the necessity of intelligent agency in life's origin. Joyce's experiment required investigator intervention at every step, using conditions and procedures that could never have occurred on the early Earth. The research challenges the plausibility of the RNA World hypothesis and demonstrates that evolving systems of RNAs could not have existed without constant intervention.

via Discovery Institute|

#evolution #gerald-joyce #origin-of-life

science-and-health2 years ago•2 min saved

Unveiling HIV's Intricate Pathway Into the Cell's Nucleus

Scientists from the University of Chicago have discovered how the HIV virus infiltrates the nucleus of a host cell, a crucial step in its replication and spread. Using simulations, they found that the virus capsid employs an electrostatic ratchet to squeeze through the cell's nuclear pore complex, with flexibility and deformation playing key roles. Understanding this process could lead to better treatments and potentially a cure for HIV, as disrupting this mechanism could hinder the virus's survival.

via ScienceAlert|

#cell-nucleus #hiv #pnas