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For many people, the aroma of freshly brewed coffee is the start of a great day. But caffeine can cause headaches and jitters in others. That's why many people reach for a decaffeinated cup instead. I'm a chemistry professor who has taught lectures on why chemicals dissolve in some liquids but not in others. The processes of decaffeination offer great real-life examples of these chemistry concepts. Even the best decaffeination method, however, does not remove all of the caffeine -- about 7 milligrams of caffeine usually remain in an 8-ounce cup. Producers decaffeinating their coffee want to remove the caffeine while retaining all -- or at least most -- of the other chemical aroma and flavor compounds.

Decaffeination has a rich history, and now almost all coffee producers use one of three common methods. All these methods, which are also used to make decaffeinated tea, start with green, or unroasted, coffee beans that have been premoistened. Using roasted coffee beans would result in a coffee with a very different aroma and taste because the decaffeination steps would remove some flavor and odor compounds produced during roasting. Here's a summary of each method discussed by Dr. Crowder:

• The Carbon Dioxide Method: Developed in the early 1970s, the carbon dioxide method uses high-pressure CO2 to extract caffeine from moistened coffee beans, resulting in coffee that retains most of its flavor. The caffeine-laden CO2 is then filtered out using water or activated carbon, removing 96% to 98% of the caffeine with minimal CO2 residue.

• The Swiss Water Process: First used commercially in the early 1980s, the Swiss water method uses hot water and activated charcoal filters to decaffeinate coffee, preserving most of its natural flavor. This chemical-free approach removes 94% to 96% of the caffeine by soaking the beans repeatedly until the desired caffeine level is achieved.

• Solvent-Based Methods: Originating in the early 1900s, solvent-based methods use organic solvents like ethyl acetate and methylene chloride to extract caffeine from green coffee beans. These methods remove 96% to 97% of the caffeine through either direct soaking in solvent or indirect treatment of water containing caffeine, followed by steaming and roasting to ensure safety and flavor retention.

"It's chemically impossible to dissolve out only the caffeine without also dissolving out other chemical compounds in the beans, so decaffeination inevitably removes some other compounds that contribute to the aroma and flavor of your cup of coffee," writes Dr. Crowder in closing. "But some techniques, like the Swiss water process and the indirect solvent method, have steps that may reintroduce some of these extracted compounds. These approaches probably can't return all the extra compounds back to the beans, but they may add some of the flavor compounds back."

Somehow, this two and a half minute skit perfectly captures the essence of the entire series.

Shamelessly posted based on a comment in another post from @[email protected]

The FTC has sent mandatory notices for information to eight companies it says engages in "surveillance pricing", the process by which prices are rapidly changed using AI based on data about customer behavior and characteristics. This process, the FTC claims, allows companies to charge different customers different prices for the same product.

The list includes Mastercard, JPMorgan Chase, Accenture and consulting giant McKinsey. It also includes software firm Task, which counts McDonald's and Starbucks as clients; Revionics, which works with Home Depot, Tractor Supply and grocery chain Hannaford; Bloomreach, which services FreshDirect, Total Wine and Puma; and Pros, which was named Microsoft's internet service vendor of the year this year. "Firms that harvest Americans' personal data can put people's privacy at risk," FTC Chair Lina Khan said in a news release. "Now firms could be exploiting this vast trove of personal information to charge people higher prices."

Top: Captain Picard and Kamala in The Perfect Mate

Bottom: Professor X and Jean Grey in X-Men: The Last Stand

Had no idea Patrick Stewart and Famke Janssen had collaborated prior to X-Men.

A solar superstorm in May caused thousands of satellites to simultaneously maneuver to maintain altitude due to the thickening of the upper atmosphere, creating potential collision hazards as existing prediction systems struggled to cope. Space.com reports:

According to a pre-print paper published on the online repository arXiv on June 12, satellites and space debris objects in low Earth orbit -- the region of space up to an altitude of 1,200 miles (2,000 kilometers) -- were sinking toward the planet at the speed of 590 feet (180 meters) per day during the four-day storm. To make up for the loss of altitude, thousands of spacecraft began firing their thrusters at the same time to climb back up. That mass movement, the authors of the paper point out, could have led to dangerous situations because collision avoidance systems didn't have time to calculate the satellites' changing paths.

The solar storm that battered Earth from May 7 to 10 reached the intensity of G5, the highest level on the five-step scale used by the National Oceanic and Atmospheric Administration (NOAA) to assess the strength of solar storms. It was the strongest solar storm to hit Earth since 2003. The authors of the paper, however, pointed out that the environment around the planet has changed profoundly since that time. While only a few hundred satellites were orbiting Earth twenty years ago, there are thousands today. The authors of the paper put the number of "active payloads at [low Earth orbit]" at 10,000. [...] The new paper points out that space weather forecasts ahead of the May storm failed to accurately predict the duration and intensity of the event, making satellite collision predictions nearly impossible.

On the upside, the storm helped to clear out some junk as defunct satellites and debris fragments spiraled deeper into the atmosphere. The authors of the report estimate that thousands of space debris objects lost several kilometers in altitude during the storm. More powerful solar storms can be expected in the coming months as the peak of the current solar cycle -- the 11-year ebb and flow in the number of sunspots, solar flares and eruptions -- is expected in late 2024 and early 2025.

The paper can be found here.

At EPFL, the Laboratory for Experimental Museology (EM+) specializes in this technology and has developed a program that turns the terabytes of data generated from the tokamak simulations and testing carried out by EPFL’s Swiss Plasma Center (SPC) into an immersive 3D visualization experience. For the general public, the visualization is a journey into a ring of fireworks illustrating a possible future source of energy; for scientists, it’s a valuable tool that renders the complex phenomena of quantum physics tangible and helps them grasp the results of their calculations.

The 3D visualization – a panorama measuring 4 meters high and 10 meters in diameter – is a faithful reproduction of the interior of EPFL’s variable-configuration tokamak (TCV), rendered in such stunning detail that it rivals even the best-quality gaming experience.

Note: The 3D visualization is a physical display at their facility. I spent far too long parsing multiple articles trying to find a link to an online visualization. The article is still good, and there are images of the visualization.

Scientists were stunned on May 30 when a rock that NASA's Curiosity Mars rover drove over cracked open to reveal something never seen before on the Red Planet: yellow sulfur crystals. Since October 2023, the rover has been exploring a region of Mars rich with sulfates, a kind of salt that contains sulfur and forms as water evaporates. But where past detections have been of sulfur-based minerals -- in other words, a mix of sulfur and other materials -- the rock Curiosity recently cracked open is made of elemental (pure) sulfur. It isn't clear what relationship, if any, the elemental sulfur has to other sulfur-based minerals in the area.

While people associate sulfur with the odor from rotten eggs (the result of hydrogen sulfide gas), elemental sulfur is odorless. It forms in only a narrow range of conditions that scientists haven't associated with the history of this location. And Curiosity found a lot of it -- an entire field of bright rocks that look similar to the one the rover crushed. "Finding a field of stones made of pure sulfur is like finding an oasis in the desert," said Curiosity's project scientist, Ashwin Vasavada of NASA's Jet Propulsion Laboratory in Southern California. "It shouldn't be there, so now we have to explain it. Discovering strange and unexpected things is what makes planetary exploration so exciting."

Two male skeletons showed signs of severe fracture and trauma injuries.

Archaeologists have hotly debated the precise cause of death of those who perished in Pompeii when Mount Vesuvius erupted in 79 CE. Did they die of asphyxiation, from the extreme heat, or from a combination of factors? A new paper published in the journal Frontiers in Earth Science examines the complicating effects of earthquakes that occurred just prior to and concurrently with the eruption. Of most interest was the discovery of two skeletons of people who likely died when their shelter collapsed around them, weakened by the seismic tremors.

The image, as it happens, comes from dozens of brain scans produced by researchers at Washington University School of Medicine in St. Louis who gave psilocybin, the compound in "magic mushrooms," to participants in a study before sending them into a functional M.R.I. scanner. The kaleidoscopic whirl of colors they recorded is essentially a heat map of brain changes, with the red, orange and yellow hues reflecting a significant departure from normal activity patterns. The blues and greens reflect normal brain activity that occurs in the so-called functional networks, the neural communication pathways that connect different regions of the brain.

The scans, published Wednesday in the journal Nature, offer a rare glimpse into the wild neural storm associated with mind-altering drugs. Researchers say they could provide a potential road map for understanding how psychedelic compounds like psilocybin, LSD and MDMA can lead to lasting relief from depression, anxiety and other mental health disorders. "Psilocybin, in contrast to any other drug we've tested, has this massive effect on the whole brain that was pretty unexpected," said Dr. Nico Dosenbach, a professor of neurology at Washington University and a senior author of the study. "It was quite shocking when we saw the effect size." Brian Mathur, a systems neuroscientist at the University of Maryland School of Medicine in Baltimore, says these findings cannot show exactly what causes the therapeutic benefit of psilocybin, but "it's possible psilocybin is directly causing" the brain-network changes. That, or it is creating a psychedelic experience that in turn causes parts of the brain to behave differently.

The next step is to determine whether psilocybin's blood-flow changes in the brain or its direct effects on neurons, or both, are responsible for the brain-network disruptions. "The best part of this work is that it's going to provide a means forward for the field to develop further hypotheses that can and should be tested," Mathur says.