Humans possess an astonishing sensory ability that often goes unnoticed.
Research has shown that people can detect geosmin, one of the main compounds responsible for petrichor, the earthy smell that appears after rain, at concentrations so tiny that they are measured in parts per trillion.
This remarkable sensitivity means that humans are estimated to be up to 200,000 times more sensitive to the smell of petrichor than sharks are to the smell of blood. While sharks have an incredible sense of smell and can detect certain substances in water at extremely low concentrations, our noses are exceptionally tuned to geosmin.
Petrichor is created when rain falls on dry soil, releasing microscopic particles into the air. These particles contain geosmin, a compound produced by soil dwelling bacteria, along with plant oils that accumulate during dry weather. The result is the fresh, earthy scent that so many people associate with the arrival of rain.
Scientists believe this extraordinary sensitivity may have helped our ancestors locate fresh water, fertile land, or healthy environments after rainfall. Whatever the reason, it gives humans a surprising sensory superpower.
So the next time you notice that unmistakable smell after a rainstorm, remember that your nose is detecting chemicals at concentrations so incredibly small that it rivals some of the most impressive sensory abilities found anywhere in the animal kingdom.
@alpaysh@elonmusk Rhetorically, I ask my patients, especially my PTSD patients, “How to you expect to heal if you keep picking at the scab?” … mental health therapists hate this
@WallStreetMav Absolutely correct. My experience with MRI w/o contrast is insurance pricing is 1200-1500 per body section vs cash is 300-400 … However, certain specialties show little or no difference e.g. oncology/chemo/XRT and pharmaceuticals. (Diagnosis is cheap, treatment is expensive)
@SmartScience No it’s more than just timing, it’s the combinations that should be considered too: e.g. calcium competes with magnesium (and wins) so they shouldn’t be taken together or with calcium rich foods (it’s difficult enough for your body to absorb magnesium by itself)
@gabedrawsX@GadSaad@mcgillu Are you saying Zionism = Jewish? Since when does a political movement = cultural or religious identity? People can be anti-Zionist without being anti-Jewish.
Scientists just did something that was supposed to be impossible.
A team at Japan's Mie University used CRISPR gene editing to remove the entire extra chromosome behind Down syndrome.
Not manage the symptoms. Remove the cause.
Down syndrome, or trisomy 21, happens when cells carry a third copy of chromosome 21. For over half a century, every treatment has focused on the effects, never the root.
Led by Dr. Ryotaro Hashizume, the researchers designed their CRISPR-Cas9 system to target only the surplus chromosome and leave the healthy two untouched. A technique they call allele-specific multiple chromosome cleavage.
It worked.
In lab-grown stem cells and in skin cells taken from people with Down syndrome, the extra chromosome was snipped out. And the corrected cells didn't just survive. They grew faster, behaved more normally, and produced fewer of the harmful byproducts tied to cellular stress and aging.
Here's the honest part most headlines skip.
This happened in cells, in a dish. Not in a living person. Some of the CRISPR cuts still hit healthy chromosomes, so the team is refining their targeting before any of this comes close to a clinic.
It's a first step, not a finish line.
But it's the first time anyone has reached the actual source of the most common chromosomal condition on Earth and pulled it out.
The thing science said couldn't be undone just got undone in a petri dish.
Source: Hashizume et al., "Trisomic rescue via allele-specific multiple chromosome cleavage using CRISPR-Cas9 in trisomy 21 cells," PNAS Nexus (2025), Mie University
imo, you are mostly your brain, but parts of you must reside elsewhere - otherwise how else do you explain sudden changes in personality, taste or interest after getting an organ transplant (e.g. a woman suddenly liking and doing skilled DYI after a kidney transplant, or another patient suddenly loving beer after their heart transplant)
@pooplius@PhysInHistory Ok except that I’m constantly arguing with Ai because it’s often wrong (the reality is that textbook knowledge often lags professional experience by 10-20 years)
No, but it’s never used all at once (unless it’s a generalized seizure, but that’s a pathological state of an electrical storm affecting the cerebrum). There seems to be parts, if affected individually or separately, that aren’t used much or have a redundant function because a person could have a stroke and never know it, if the stroke occurred in what we call “non eloquent” part of the brain … get enough of these over time and you get vascular dementia.
@ArizAshraf22463@PhysInHistory The brain. As an example, would be a simple seizure (abnormal, excessive electrical activity in brain) in the temporal lobe can cause unprovoked intense feelings of fear, panic, joy or sadness)