Lifeboat Foundation

Carl Sagan explores the life and legacy of the ancient Greek polymath Eratosthenes, who, in the 3rd century BCE, not only understood Earth to be spherical, but was able to calculate its circumference with remarkable accuracy. In detailing Eratosthenes’ ingenious methods, Sagan provides a fascinating science history lesson that doubles as a tribute to the remarkable ingenuity of ancient thinkers, who were able to uncover extraordinary truths with the simplest of tools.

Nanomedicine uses nanomaterials [e.g., carbon nanotubes (CNTs), nanoparticles, and nanodiscs] or organic nanostructures (e.g., DNA origami and liposomes) for drug delivery (8–10), medical imaging (11–14), and tissue regeneration (15). Nanomaterials offer therapeutic efficacy through their tissue permeation, interaction with an external energy source, and capability to be combined with other therapeutic modalities (16, 17). Because we recently demonstrated that GBM cells are mechanosensitive (18), we set to use nanomaterials to develop a nanoscale mechanical approach to treat GBM. Mechanical perturbation has been investigated as an approach to target cancer cells. For example, magnetic field–actuated nanomaterials compromise the integrity of plasma membrane, leading to the death of in vitro–cultured GBM cells (19) and breast cancer cells (20). GBM cells, which were preincubated with magnetic nanoparticles, were implanted into mice to generate xenograft tumors. A rotating magnetic field, which was then applied to these magnetic particles–harboring tumors, suppressed GBM growth (21). Similarly, magnetic field mobilization of mitochondria-targeting magnetic nanoparticle chains demonstrated efficacy in inhibiting GBM growth in mice (22). While these studies showed that magnetic field–controlled nanomaterials can be used in cancer treatment, the utility of magnetic nanomaterials in treating chemoresistant tumors, the root cause of tumor relapse and patient death, remains unexplored.

GBM displays an extreme level of heterogeneity at genomic, epigenetic, biochemical signaling, and cellular composition levels (23). The heterogeneous nature of GBM confers treatment resilience to tumors and leads to a unifying therapy resistance mechanism; i.e., suppressing selected proteins or biochemical pathways provides a fertile ground for alternative signaling mechanisms, which are not targeted by the given therapy, to fuel GBM growth (24). In other words, the “whack-a-mole” approach failed to benefit patients with GBM for decades. For this reason, we hypothesized that nanomaterial-based mechanical treatment of cancer cells, rather than specific targeting of signaling pathways, can overcome the therapy resistance of this biologically plastic disease. To this end, we engineered a mechanical nanosurgery approach using magnetic CNTs (mCNTs; nanotubes with carbon surface and a cavity filled with iron particles) based on the following reasons.

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Device’s ultrashort pulses could capture the motion of individual molecules.

Australian scientists have just discovered a new species of arachnid, dubbed the giant trapdoor spider, in Queensland. It’s huge, bright red, and it can live for up to two decades.

Before you panic, we should note that trapdoor spiders aren’t considered a threat to humans. While they are venomous, their bites aren’t known to have any lasting effect on people, reports the BBC. Besides, hikers rarely encounter them; the spiders are nocturnal and spend most of their lives underground. And while they’re big for trapdoor spiders, they’re not as massive as, say, tarantulas or giant desert scorpions.

Female giant trapdoor spiders can grow up to two inches long. That’s about twice the size of other trapdoor spiders. Male trapdoor spiders are slightly smaller.

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Sam Altman is the CEO of OpenAI, the company behind GPT-4, ChatGPT, DALL-E, Codex, and many other state-of-the-art AI technologies.

Continue reading “OpenAI CEO responds to Jordan Peterson criticism | Sam Altman and Lex Fridman” »

Nuclear physicists may have finally pinpointed where in the proton a large fraction of its mass resides. A recent experiment carried out at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility has revealed the radius of the proton’s mass that is generated by the strong force as it glues together the proton’s building block quarks. The result was recently published in Nature.

One of the biggest mysteries of the proton is the origin of its mass. It turns out that the proton’s measured mass doesn’t just come from its physical building blocks, its three so-called valence quarks.

“If you add up the Standard Model masses of the quarks in a proton, you only get a small fraction of the proton’s mass,” explained experiment co-spokesperson Sylvester Joosten, an experimental physicist at DOE’s Argonne National Laboratory.

Scientists relied on the holographic principle, which suggests that the two existing theories – particles and gravity – are equivalent.

Combining an optical tweezer technology called C-trap that manipulates a single molecule of DNA and a novel approach, researchers were able to receive a detailed view into how cells find and repair damaged DNA.

Their findings are described in an article titled, “Single-molecule analysis of DNA-binding proteins from nuclear extracts (SMADNE),” published in Nucleic Acids Research.

In the new study, the researchers used the C-trap to investigate how different DNA repair proteins identify and bind to their respective forms of damage.

More than 260 fragments of animal bones have been found at the monument.

Artnet News, March 29, 2023.