Start at 4:29. Really interesting video. Instead of ranking countries by wealth, they proposed tracking people happiness, by asking how close you feel to your ideal life. Turns out it does track fairly well to wealth. But a related question "how happy were you yesterday?" ranks very differently and is unrelated to wealth.
Sunday, April 27, 2025
Saturday, April 26, 2025
Dark clothing increases car crashes with pedestrians
Amongst a host of other associations, a study found "crashes involving pedestrians in dark clothing" as a risk factor for pedestrian motor vehicle accidents.*
Even during daytime, "Motorists were more likely to stop for a brightly-clothed pedestrian."
A crosswalk warning sign, unfortunately, had no effect. "The presence of a warning sign located 48 meters before the crosswalk had no significant effect on motorists' yielding under daytime conditions."
However, a sign between the lanes of traffic was more effective at getting drivers to stop than a flashing yellow light.
"the produced very high levels of driver yielding, and that it was as effective as the 2 more expensive treatments."
* Other associations were:
"elderly pedestrian (>64 years) alcohol impairment resulting in fatalities, crashes in an open country location with a high posted speed limit, crashes involving pedestrians in dark clothing on high-speed (50–55 mph) roadways, alcohol-impaired driver involvement in crashes on two-way roads without physical separation, severe injury crashes at intersections, male pedestrian crashes on midblock locations during weekends, and young (15–24 years) female driver's involvement in crashes while pedestrians were walking against the traffic."
Wednesday, April 23, 2025
Cooperative problem solving by ants and humans.
What a great illustration of cooperative problem-solving by both ants and humans. https://www.facebook.com/share/r/1EYjPwaRS8/
Tuesday, April 22, 2025
New pollen-replacing food for honey bees brings hope for survival
"Until this study, honey bees were the only livestock that could not be maintained on a man-made feed...newly developed food source resembles human "Power Bars." These are placed directly into honey bee colonies, where young bees process and distribute the essential nutrients to larvae and adult bees...tested thousands of combinations of ingredients on honey bees over more than 10 years to create this feed.
...shows in commercial field conditions that providing nutritionally stressed colonies with our pollen-replacing feed results in a major measurable step change in colony health compared to current best practices...This breakthrough addresses one of the growing challenges faced by honey bees: lack of adequate nutrition in their environment."
"A critical discovery within the research is the role of isofucosterol, a molecule found naturally in pollen that acts as a vital nutrient for honey bees...severe challenge of high annual colony mortality, with recent reports indicating crisis-level losses, underscores the urgency of this innovation"
Laser speckle interferometry
Laser speckle interferometry probes beneath an opaque surface for subtle movement. In this example it's detecting loose wall fragments.
Conservation of ancient paintings is a fine balance of removing surface contaminants without harming the underlying paint. This method, developed over 7 painstaking years, revolutionizes that by dynamically analyzing in real time how deep and how far the solvent is penetrating the damaged surface.
"With nano-motion imaging we found the sweet spot where the varnish was removed without significant solvent im-pact to the paint layer."
https://www.iiconservation.org/sites/default/files/documents/2025-04/nic-magazine-apr-may-2025-compressed_0.pdf Sunday, April 20, 2025
Complexity of computer simulations
This professor always does a mesmerizing job of describing the challenges of getting a computer to simulate light reflections and flexible deformations. Worth subscribing to - every episode over 10 years has been interesting. He saves the best for last in this video - simulation of ferrofluids at 5:12
Related: I bought my daughter a ferrofluid speaker from Amazon, and she loves it.
Friday, April 18, 2025
Economists dropped $10M in rural Africa
A randomized experiment where money was directly transferred to poverty-stricken individuals solved 2 long-standing macroeconomic questions:
1) inflation was not increased - because the economy was constrained by demand, that is, plenty of people had not enough work, so extra money allowed them to work more
2) the money multiplied, in fact by 2.5 times - poor people are more likely to spend than to save newfound wealth, which in turn is mostly spent by the recipients thereby increasing the economy more than once, before it eventually leaves the local economy.
4:14 It turns out that giving money directly to poor people without any middlemen produced greater nutritional benefits than the same dollars spent on supplying food. Giving money directly to individuals 14:19 is more effective than sending it to organizations where, because of corruption and inefficiency, only a small percentage of donated funds reach poor individuals.
Wednesday, April 16, 2025
Drug-induced synaptogenesis
I knew that psilocybin induces synaptogenesis (https://journals.sagepub.com/doi/abs/10.1177/02698811241249436 ) but didn't know that ketamine did so also, let alone so rapidly. ( "By the 2-hour time point, treatment significantly increased the probability of glutamate-evoked spinogenesis to ~50%."
Monday, April 14, 2025
Shrubs, not grasses, pull water from deep roots during drought
"a strong case against the idea that those plants use their deep roots to find moisture during times of scarcity. In fact, they might not be using them to draw moisture at all...prairie has survived droughts, grazing, and fire. The root system beneath these plants plays a major role in that resilience, but not in the way many of us have been taught...Despite having very deep roots, most prairie grasses pull water primarily from the top 10 inches or so of the soil...found that shrubs pull water from much deeper in the soil than grasses and forbs, starting at about 18 inches and reaching down to 8 or 10 feet...species such as sumac and dogwood, but not to more forb-like shrubs such as leadplant or New Jersey tea...Fortunately, while shrubs seem to have some serious advantages belowground, they still have a major disadvantage above ground, which is that their growing points are up in the air. Grasses produce new tillers (aboveground stems) from buds at or below the ground surface. That means that when they are grazed or burned off, they only lose the aboveground plant material they've invested in during the current growing season. If that defoliation occurs during the dormant season, it really doesn't bother them at all because all their living biomass is safely belowground. Shrubs, however, put on new growth from the tips of their aboveground stems. When fire comes through and destroys all their aboveground tissue, they lose a considerable investment, even during the dormant season, and have to start rebuilding from the ground..."
https://prairieecologist.com/2019/09/17/a-deep-rooted-prairie-myth/
Thursday, April 10, 2025
Thomas A. Edison - Opportunity is missed by most people...
"Opportunity is missed by most people because it is dressed in overalls and looks like work."
-Thomas A. Edison
Robots learning to walk by trial and error
I find it fascinating to watch robots learn to walk by reinforced deep learning.
2 hours to learn to walk
Underwater stretchy tape
https://youtu.be/Z3BHrzDHoYo?si=oJ2F1MPJk59BQo9e
What? Incredible camouflage and protection by gluing rocks to its body.
Locating drones, aircraft, and even asteroids cheaply
https://youtu.be/m-b51C82-UE?si=mo8M3wu_0bI5TzBV
I love a concept like this, much like digital subtraction angiography - get sophisticated data by combining multiple sources of very cheap data acquisition.
Wednesday, April 9, 2025
Orange peel dump site spawns rich biodiversity
In 1997, ecologists Daniel Janzen and Winnie Hallwachs approached an orange juice company in Costa Rica with an off-the-wall idea. In exchange for donating a portion of unspoiled, forested land ...the park would allow the company to dump its discarded orange peels and pulp, free of charge, in a heavily grazed, largely deforested area nearby...offloading over 12,000 metric tons of sticky, mealy, orange compost onto the worn-out plot...16 years later...the experiment resulted in a "176 percent increase in aboveground biomass...Compared to the adjacent plot, which was dominated by a single species of tree, the site of the orange peel deposit featured two dozen species of vegetation, most thriving...greater biodiversity, richer soil, and a better-developed canopy"
Wednesday, April 2, 2025
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