Previously, a yield strength of 5,000 pounds per square inch (psi) was enough for concrete to be rated as “high strength,” with the best going up to 10,000 psi. The new UHPC can withstand 40,000 psi or more.

The greater strength is achieved by turning concrete into a composite material with the addition of steel or other fibers. These fibers hold the concrete together and prevent cracks from spreading throughout it, negating the brittleness. “Instead of getting a few large cracks in a concrete panel, you get lots of smaller cracks,” says Barnett. “The fibers give it more fracture energy.”

The study analyzed data from 258 UK Uber drivers over more than 1.5 million trips between 2016 and 2024. This revealed a significant shift when Uber introduced a dynamic pricing algorithm in 2023. Passengers now pay more per trip, but drivers' earnings have declined. Adjusted for inflation, drivers' hourly income fell from over £22 to just over £19 before operating costs, and drivers are spending more unpaid time waiting for rides than before. Uber's commission has risen from around 25% to 29% and in some cases, Uber took over half the value of the fare.

Kletetschka said his theory overcomes some of the problems with earlier three-dimensional time theories that are based on traditional physics.

Those earlier theories, for example, describe multiple time dimensions in which cause-and-effect relationships are potentially ambiguous. Kletetschka's theory ensures that causes still precede effects, even with multiple time dimensions, just in a more complex mathematical structure.

In three-dimensional time, the second and third dimensions are thought by some researchers, notably theoretical physicist Itzhak Bars of the University of Southern California, to become apparent, or unfold, at levels of extreme energy such as during the early universe or in high-energy particle interactions..

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His framework accurately reproduces the known masses of particles such as electrons, muons and quarks and also explains why these particles have these masses.

The researchers found an average of around 100 microplastic particles per liter in glass bottles of soft drinks, lemonade, iced tea and beer. That was five to 50 times higher than the rate detected in plastic bottles or metal cans.

"We expected the opposite result," Ph.D. student Iseline Chaib, who conducted the research, told AFP.

"We then noticed that in the glass, the particles emerging from the samples were the same shape, color and polymer composition—so therefore the same plastic—as the paint on the outside of the caps that seal the glass bottles," she said.

The paint on the caps also had "tiny scratches, invisible to the naked eye, probably due to friction between the caps when there were stored," the agency said in a statement.

This could then "release particles onto the surface of the caps," it added.

They use stacked transparent color sensors, like Foveon camera sensors used to.

In numerous experiments, the researchers put the two prototypes, which differ in their readout technology, through their paces. Their results prove the advantages of perovskite: the sensors are more sensitive to light, more precise in color reproduction and can offer a significantly higher resolution than conventional silicon technology.

The fact that each pixel captures all the light also eliminates some of the artifacts of digital photography, such as demosaicing and the moiré effect.

Aagesen singled out the role of the Spanish grid operator REE and certain energy companies she did not name which disconnected their plants "inappropriately... to protect their installations."

She also pointed to "insufficient voltage control capacity" on the system that day, due in part to a programming flaw, stressing that Spain's grid is theoretically robust enough to handle such situations.

Due to these misjudgments "we reached a point of no return with an uncontrollable chain reaction" that could only have been managed if steps had been taken beforehand to absorb the overvoltage problems, she added.

In the world of black holes, there are generally three size categories: stellar-mass black holes (about five to 50 times the mass of the sun), supermassive black holes (millions to billions of times the mass of the sun), and intermediate-mass black holes with masses somewhere in between.

While we know that intermediate-mass black holes should exist, little is known about their origins or characteristics—they are considered the rare "missing links" in black hole evolution.

The James Webb Space Telescope's deepest view of a single target yet depicts spinning arcs of light that are galaxies from the universe's distant past, the European Space Agency said Tuesday.

The new image took the world's most powerful telescope more than 120 hours to capture, making it the longest Webb has ever focused on a single target.

For the past decade, scientists have been trying to get to the bottom of what seemed like a major inconsistency in the universe. The universe expands over time, but how fast it's expanding has seemed to differ depending on whether you looked early in the universe's history or the present day. If true, this would have presented a major problem to the gold-standard model that represents our best understanding of the universe.

But thanks to the new James Webb Space Telescope, scientists from the University of Chicago have been able to take new and better data—suggesting there may be no conflict after all.

A team from MIT and the Woods Hole Oceanographic Institution (WHOI) has developed an image-analysis tool that cuts through the ocean's optical effects and generates images of underwater environments that look as if the water had been drained away, revealing an ocean scene's true colors. The team paired the color-correcting tool with a computational model that converts images of a scene into a three-dimensional underwater "world," that can then be explored virtually.

The researchers have dubbed the new tool SeaSplat, in reference to both its underwater application and a method known as 3D Gaussian splatting (3DGS), which takes images of a scene and stitches them together to generate a complete, three-dimensional representation that can be viewed in detail, from any perspective.

For now, the method requires hefty computing resources in the form of a desktop computer that would be too bulky to carry aboard an underwater robot. Still, SeaSplat could work for tethered operations, where a vehicle, tied to a ship, can explore and take images that can be sent up to a ship's computer.

From this paper:

Data points indicate best performers by year of market introduction.

The magnified plot shows progress in cool white LEDs from 1996 to 2020. For comparison, efficacies of best performers in legacy lighting technologies for 2020 are shown as coloured horizontal lines.

Note the logarithmic scale of the vertical axis on the main plot and the linear scale on the magnified plot.

From this article:

most improvements in the energy efficiency of LEDs were driven by research and development efforts. Surprisingly, however, R&D contributed relatively little to reductions in the cost of the devices, which were instead linked to economies of scale and continuous manufacturing process improvements over time.