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Photosynthesis is one of the most important chemical processes on Earth. (Image credit: Shutterstock)

One of the most well-studied chemical processes in nature, photosynthesis, may not work quite how we thought it did, scientists have accidentally discovered.

Photosynthesis is the process by which plants, algae and some bacteria convert carbon dioxide and water into oxygen and sugars to use as energy. To do this, the organisms use sunlight to oxidize, or take electrons from, water; and reduce, or give electrons to, carbon dioxide molecules. These chemical reactions require photosystems — protein complexes that contain chlorophyll, a pigment that absorbs light and gives plant leaves and algae their green color — to transfer electrons between different molecules.

In the new study, published March 22 in the journal Nature (opens in new tab) , researchers used a new technique, known as ultrafast transient absorption spectroscopy, to study how photosynthesis works at a timescale of one quadrillionth of a second (0.000000000000001 second) for the first time. The team was initially trying to figure out how quinones — ring-shaped molecules that can steal electrons during chemical processes — impact photosynthesis. But instead, the researchers found that electrons could be released from photosystems much earlier during photosynthesis than scientists previously believed was possible.

“We thought we were just using a new technique to confirm what we already knew,” study co-author Jenny Zhang (opens in new tab) , a biochemist specializing in photosynthesis at the University of Cambridge in England, said in a statement (opens in new tab) . “Instead, we found a whole new pathway, and opened the black box of photosynthesis a bit further.”

Related: New ‘artificial’ photosynthesis is 10x more efficient than previous attempts 

Photosynthetic algae viewed under the microscope. Their green color is the result of the pigment chlorophyll found inside photosystems. (Image credit: Shutterstock)

Two photosystems are used during photosynthesis: photosystem I (PSI) and photosystem II (PSII). PSII primarily provide electrons to PSI by taking them from water molecules: PSI then further excites the electrons before releasing them to eventually be given to carbon dioxide to create sugars, via a series of complex steps. 

Past research had suggested that the protein scaffolding in PSI and PSII was very thick, which helped to contain electrons within them before being passed on to where they were needed. But the new ultrafast spectroscopy technique revealed that the protein scaffolding was more “leaky” than expected and that some electrons could escape from the photosystems almost immediately after light was absorbed by the chlorophyll within the photosystems. These electrons could therefore reach their destinations faster than expected.

“The new electron transfer pathway we found here is completely surprising,” Zhang said. “We didn’t know as much about photosynthesis as we thought we did.”

The electron leaking was observed in both isolated photosystems and within “living” photosystems inside cyanobacteria.RELATED STORIES—Plant leaves spark with electricity during thunderstorms — and that could be altering our air quality in unpredictable ways

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In addition to rewriting what we know about photosynthesis, the discovery opens up new avenues for future research and biotechnology applications. The team believes that by “hacking” photosynthesis to release more of these electrons at earlier stages, the process could become much more efficient, which could help produce plants that are more resistant to sunlight or be replicated artificially to create renewable energy sources to help combat climate change, according to the statement. However, much more research is needed before this can happen.

“Many scientists have tried to extract electrons from an earlier point in photosynthesis, but said it wasn’t possible because the energy is so buried in the protein scaffold,” Zhang said. “The fact that we can [potentially] steal them at an earlier process is mind-blowing.”

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Fire and flops: Six Stanley Cup playoff teams that are either impressing or disappointing

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Fire and flops: Six Stanley Cup playoff teams that are either impressing or disappointing

The first week-plus of the 2024 Stanley Cup playoffs has already provided much in the way of excitement and bone-crunching action. The average playoff game has featured 89.5 combined hits by both teams — nearly double the league average (45.5) from the regular season, according to ESPN Stats & Information.

With so much chaos, there are plenty of teams that have exceeded — or fallen short of — expectations already.

For instance, the defending champion Vegas Golden Knights have been mighty impressive, taking a 2-1 lead over a Dallas Stars team that had led the league in goal differential during the regular season. But on the disappointing side, the Toronto Maple Leafs have fallen behind 3-1 in their series against the Boston Bruins, and the Los Angeles Kings are in a 3-1 hole versus the Edmonton Oilers.

Let’s run through the clubs that fit into each category, based on their playoff goal differentials as compared with what we’d expect from their pre-series power ratings and their opponent’s (adjusting for home-ice advantage). We’ll also highlight a player who has contributed to the state of his team, for good or bad, in the playoffs thus far.

We’ll start with the positive side of things. Here are three teams that have impressed the most:

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Polestar shows off 5 GT charging capabilities, replenishing 10-80% in just ten minutes [Video]

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Polestar shows off 5 GT charging capabilities, replenishing 10-80% in just ten minutes [Video]

Polestar is showcasing the charging capabilities of the upcoming Polestar 5 sports sedan using a prototype model and StoreDot’s Extreme Fast Charging (XFC) technology. This is the first EV to test StoreDot’s ultra-fast charging technology, and the initial tests are quite promising.

When it arrives, the Polestar 5 will be—you guessed it—the fifth model in the Geely-owned automaker’s EV portfolio. The all-electric sports sedan’s inception stems from the Precept concept, and Polestar continues to be one of the few automakers that actually evolves its concepts into production vehicles.

The production prototype version of the Polestar 5 debuted in late 2021, equipped with carriage doors and a “Smart Zone” grille that houses many of the sensors for the EV’s ADAS. In July 2023, a camouflaged prototype of the 5 appeared publicly at the Goodwood Festival of Speed, touting 884 horsepower and Polestar’s 800V architecture that will enable ultra-fast charging speeds.

By November 2023, we learned that EV battery specialist StoreDot would trial its new 100in5 battery technology in the Polestar 5, giving the 4-door GT charging capabilities of garnering 100 miles of range in just 5 minutes.

These fast-charging cells have since become the nucleus of StoreDot’s I-BEAM XFC concept design, which is targeting mass production later this year. Before the Polestar 5 and fast-charging architecture hit the market, however, both Polestar and StoreDot are showing off those capabilities, and they’re quite impressive.

  • Polestar 5 charging
  • Polestar 5 charging

Polestar 5 prototype surpasses 370 kW charging rate

Per Polestar, the first verification prototype of the 5 GT successfully demonstrated the promised charging rates enabled by StoreDot’s XFC technology, charging from 10-80% in just ten minutes. The companies shared that the 5 held a consistent charge rate during the session, starting at 310 kW before surpassing 370 kW.

By comparison to the current market, those are some of the higher charge rates achieved by a BEV and offer encouraging results for a future in which drivers can park, recharge, and get back on the road more similarly to the time it would take to stop and refill an ICE vehicle at a gas station. Polestar CEO Thomas Ingenlath shared a similar sentiment:

Time is one of life’s greatest luxuries, and as a manufacturer of luxury electric performance cars, we need to take the next step to address one of the biggest barriers to EV ownership – charging anxiety. With this new technology, on longer journeys when drivers do stop they’ll be able to spend less time charging and be back on the road faster than before. In fact, that stop time will be more akin to what they experience with a petrol car today.

The Polestar 5 prototype houses a specially commissioned 77 kWh pack, with charging speeds bolstered by StoreDot’s silicon-dominant cells. However, the automaker says the battery pack has the capability to be increased to at least 100 kWh, enabling the BEV to recoup 200 miles of range in a ten-minute charge.

When the Precept became the Polestar 5, the automaker aimed to reach the market in 2024. However, the company’s current focus is on the two SUVs that will precede the GT – the Polestar 3 and 4. While we await the Polestar 5’s arrival on the market, you can check out its prototype’s charging capabilities in the video below:

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Source: Buffs RB Edwards to transfer to K-State

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Source: Buffs RB Edwards to transfer to K-State

Kansas State football landed Colorado‘s leading rusher from last season, as running back Dylan Edwards committed to the Wildcats on Sunday, a source confirmed to ESPN.

Edwards also appeared to confirm the news, posting a photo of himself in a Kansas State uniform on X.

As a true freshman, Edwards rushed for 321 yards for the Buffaloes in 2023. He also caught 36 passes for 299 yards and four touchdowns. Three of those receiving touchdowns came in his Colorado debut, when the Buffaloes knocked off TCU 45-42 in the season opener.

Edwards was ranked the No. 140 overall recruit in last year’s class. The Derby, Kansas, native committed to play for both Kansas State and Notre Dame before signing with new Colorado coach Deion Sanders.

Edwards will likely play behind Kansas State running back DJ Giddens, who rushed for 1,226 yards and 10 touchdowns last season, while also giving the Wildcats a proven receiving threat out of the backfield.

Kansas State plays at Colorado on Oct. 12 next season.

247 Sports first reported the news of Edwards’ commitment.

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