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One protein, two opposing roles: This ‘compelling’ study shows how the same signalling molecule can drive either protrusion or retraction in migrating cells depending on its concentration and activation dynamics.

eLife - the journal

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10,614 次观看 • 1 年前 •via X (Twitter)

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This footage shows a jaguar and a puma using the same trail, but not at the same time. These two big cats were filmed days apart in the Osa Peninsula, Costa Rica, and their movements were combined into one video to highlight how they navigate the same environment

This footage shows a jaguar and a puma using the same trail, but not at the same time. These two big cats were filmed days apart in the Osa Peninsula, Costa Rica, and their movements were combined into one video to highlight how they navigate the same environment

Nature Unedited

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You’re gonna remember this one!! This is a case w/either the most crazy or most predictable ending—depending on how you look at it! It’s in the “I’ve never seen that in my 15 year career” column Patient who had a mesenchymal stem implantation for a remote spinal cord injury. Can you see what happened? Did something go wrong or go right? Watch to the end to find out!!!

You’re gonna remember this one!! This is a case w/either the most crazy or most predictable ending—depending on how you look at it! It’s in the “I’ve never seen that in my 15 year career” column Patient who had a mesenchymal stem implantation for a remote spinal cord injury. Can you see what happened? Did something go wrong or go right? Watch to the end to find out!!!

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A single E. coli cell, placed on a dish, will become 70 billion cells in just 12 hours. That’s exponential growth. But a new preprint shows that it's possible to engineer E. coli to grow linearly instead, where only one daughter cell continues dividing and the other stops. First, some context. In nature, there is a bacterium called Mycobacterium smegmatis (initially discovered in 1884 in ulcers scraped from syphilis patients.) M. smegmatis is weird because it divides asymmetrically. These cells grow only from one end, and all their cell wall biosynthesis machinery is located on that one end. So when the cell divides, one daughter gets this machinery and the other gets nothing. The daughter that gets the machinery can keep dividing immediately, but the other daughter has to remake all that machinery from scratch, so its growth is delayed. E. coli doesn’t grow like this. When it divides, it pinches in the middle and splits everything evenly. Enzymes, metabolites, and proteins get partitioned more or less randomly between the two daughters. For the new preprint, though, researchers engineered E. coli to behave more like M. smegmatis. Here is how they did it: First, they deleted a gene called cyaA, which encodes an enzyme (adenylate cyclase) that makes a molecule called cAMP. cAMP is SUPER IMPORTANT! It is a nutrient sensor that instructs E. coli to switch on genes that help it digest non-glucose carbon sources when glucose is scarce. Without cAMP, E. coli cells growing on alternative carbon sources will starve; they won’t know how to eat the food. Next, they added back a “split” version of the cyaA gene into the cells. In other words, they split the gene in two so that each half of the enzyme is made separately. Cells can only make cAMP, and thus eat non-glucose carbon sources, if these two halves come together. To facilitate that “coming together,” the researchers also fused the split cyaA proteins to sticky proteins that clump together, and to a fluorescent protein (to make it easy to track these molecules in the cell.) So now some interesting things start to happen if you grow E. coli on a growth medium lacking glucose. As the cell grows, its cyaA “halves” start clumping together into a giant ball. Inside the aggregate, the two enzyme halves come together and make cAMP. And when the cell gets big enough and divides, the clump of cyaA RANDOMLY goes to either daughter cell #1 or #2. The daughter that gets the aggregate (called PA+ in this paper) can keep dividing. The daughter that doesn’t (PA–) cannot. It still grows a few times — about four divisions — because it inherits some leftover cAMP from its mother. But after that, the metabolite is diluted away, and the cell stops growing. PA+ cells went through about 23 divisions on average before their aggregate decayed. And the population of cells, as a whole, grew linearly. This paper is cool because there are many applications where exponential growth is too unpredictable and, perhaps, unsafe. If you want to engineer bacteria to deliver drugs, clean up waste, or live in the gut, you don’t want them to double uncontrollably. This paper shows you can make them expand in a controlled, linear way. Alas, mutations could break this whole engineered system. A mutation that restores cyaA, for example, would give cells a new way to make cAMP. Mutations that make the aggregates split between daughters would break the asymmetry, too. But still, I really enjoy proof-of-concept engineering papers like this.

A single E. coli cell, placed on a dish, will become 70 billion cells in just 12 hours. That’s exponential growth. But a new preprint shows that it's possible to engineer E. coli to grow linearly instead, where only one daughter cell continues dividing and the other stops. First, some context. In nature, there is a bacterium called Mycobacterium smegmatis (initially discovered in 1884 in ulcers scraped from syphilis patients.) M. smegmatis is weird because it divides asymmetrically. These cells grow only from one end, and all their cell wall biosynthesis machinery is located on that one end. So when the cell divides, one daughter gets this machinery and the other gets nothing. The daughter that gets the machinery can keep dividing immediately, but the other daughter has to remake all that machinery from scratch, so its growth is delayed. E. coli doesn’t grow like this. When it divides, it pinches in the middle and splits everything evenly. Enzymes, metabolites, and proteins get partitioned more or less randomly between the two daughters. For the new preprint, though, researchers engineered E. coli to behave more like M. smegmatis. Here is how they did it: First, they deleted a gene called cyaA, which encodes an enzyme (adenylate cyclase) that makes a molecule called cAMP. cAMP is SUPER IMPORTANT! It is a nutrient sensor that instructs E. coli to switch on genes that help it digest non-glucose carbon sources when glucose is scarce. Without cAMP, E. coli cells growing on alternative carbon sources will starve; they won’t know how to eat the food. Next, they added back a “split” version of the cyaA gene into the cells. In other words, they split the gene in two so that each half of the enzyme is made separately. Cells can only make cAMP, and thus eat non-glucose carbon sources, if these two halves come together. To facilitate that “coming together,” the researchers also fused the split cyaA proteins to sticky proteins that clump together, and to a fluorescent protein (to make it easy to track these molecules in the cell.) So now some interesting things start to happen if you grow E. coli on a growth medium lacking glucose. As the cell grows, its cyaA “halves” start clumping together into a giant ball. Inside the aggregate, the two enzyme halves come together and make cAMP. And when the cell gets big enough and divides, the clump of cyaA RANDOMLY goes to either daughter cell #1 or #2. The daughter that gets the aggregate (called PA+ in this paper) can keep dividing. The daughter that doesn’t (PA–) cannot. It still grows a few times — about four divisions — because it inherits some leftover cAMP from its mother. But after that, the metabolite is diluted away, and the cell stops growing. PA+ cells went through about 23 divisions on average before their aggregate decayed. And the population of cells, as a whole, grew linearly. This paper is cool because there are many applications where exponential growth is too unpredictable and, perhaps, unsafe. If you want to engineer bacteria to deliver drugs, clean up waste, or live in the gut, you don’t want them to double uncontrollably. This paper shows you can make them expand in a controlled, linear way. Alas, mutations could break this whole engineered system. A mutation that restores cyaA, for example, would give cells a new way to make cAMP. Mutations that make the aggregates split between daughters would break the asymmetry, too. But still, I really enjoy proof-of-concept engineering papers like this.

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The Dottore we saw in the 6.2 AQ is absolutely NOT Omega - A mini 🧵I suppose YES THIS CONTAINS LEAKS AND SPOILERS We know the VA likes to play with his voice depending on the segment, I can't help but think the one that we saw recently is either OG Dottore or a new segment 1/5

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How can Britain be “Judeo-Christian” if Jews were expelled from Britain for four centuries and they have always been <1% of the population? Everyone who uses this term is either a propagandist or a sheep. This is one of the obvious tells about whether someone is on our side.

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crazy.. photoshop but for video is here seedance 2.0 now can edit video in layers like ground, sky, bg or objects separately on arcads AI.. and keeps camera and character motion perfectly the same.. this is revolution for film industry here's how to do:

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If you have Cancer, this is your visualization. That is a cancerous cell reaching Apoptosis and Necrosis—they are gone. — Natural Killer (NK) cells play a the primary role in the immune system's defense against cancer. They induce cancer cell death primarily through two mechanisms: Apoptosis Necrosis Apoptosis is a programmed, non-inflammatory form of cell death, while necrosis is a more abrupt and inflammatory process. In many cases, NK cells can trigger a combination of both, leading to mixed forms of cell death. This dual capability allows NK cells to effectively target and destroy all tumor cells. Their ability to act without prior sensitization makes them vital for early cancer surveillance and curing existing cancer. One of the only ways cancer never starts or stops entirely is NK cells. They are the guerrilla warfare troops that never sleep. This is why it is vital for BioShield by to be approved, NOW for every cancer, not just a single cancer type. With the rest needing years and years of tests. Cancer is cancer, unregulated cell division and NK cells are NK cells. The ONLY thing that stops BioShield is government betrayal, and organized corruption disguised as following the “regulations” designed by the entrenched gatekeepers of corporate protection. Everyone knows it works that has even a molecule of biological understanding. Now you know.

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Here’s a video of a McDonald's pneumatic ketchup/mustard dispenser that never made it to restaurants (post below). For decades we had two separate dispensers: one for ketchup and one for mustard. We’re looking to make our kitchens faster, one second at a time. They’re pretty efficient, but you had to pick up two different dispensers. Now there’s a single dual-purpose version. It dispenses both at once or either one, depending on how you move the black handle (left for mustard, center for both, right for ketchup). Yes, it’s probably over-engineered. Yes, it works. Yes, it saves time.

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🔋 One more push ahead, and even the safe and cozy Yaniv can already be seen. Some starving howls are following along, closer and louder every second. The backpack is full of precious habar from a foray, though no breath to keep it further. Whoever was there knows… In moments like this, you should start to say goodbyes to the habar or your life, depending on one’s values. For that kind of mishap, experienced stalkers got an ace in the can, the same as 16 years ago. Reliable. Tasty. And refreshing, how it should be. Be NON STOP by nature, but keep a few in your stash. Non Stop🤝S.T.A.L.K.E.R. OFFICIAL — just like on the first journey, officially together again! #Stalker2 x #NonStopEnergy x #NonStoppable

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‼️🇺🇸 Two Turnin Two Burnin. USS Milius in Motion 🔥 The waves are rough yet this destroyer moves with steady force as DDG 69 USS Milius shows what it can do. It is a guided missile destroyer equipped with the Aegis system that tracks aircraft and missile threats with remarkable precision. It carries vertical launch cells for Tomahawk and Standard Missiles and uses a powerful five inch naval gun for surface engagements. Its advanced sensors and sonar give it strong reach against submarines, making it a fully capable multi mission warship.

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Uranium, a silvery-gray radioactive metal, is found in Zamfara State, Nigeria, though no large-scale mining is currently in operation. In its natural form, uranium ore can appear black, yellow, or green, depending on its mineral composition. While weakly radioactive, uranium poses significant risks if inhaled, ingested, or improperly handled, as it emits alpha radiation and is chemically toxic to the kidneys. The greatest dangers come from uranium dust, radon gas exposure, and improper waste disposal, which can lead to environmental contamination and health hazards like lung cancer. Shockingly, in this a recent video, allegedly from Zamfara mines, it can be seen and heard how people handle uranium, completely unaware of the grave risks involved. In the video, it can be heard that one person recording was telling another called Yushau in Hausa about the quantity of the metal available (8 to 10 kilograms), further exposing the dangerous ignorance surrounding its handling. This reckless exposure highlights the urgent need for government intervention. This further highlights why the authorities must manage and handle the mining crisis in those locations to avoid exposing people to dangerous gasses that would continue to damage their organs. NB: As of February 20, 2025, the market price of uranium is roughly $143 (₦214, 500) per kilogram. (Source:

Uranium, a silvery-gray radioactive metal, is found in Zamfara State, Nigeria, though no large-scale mining is currently in operation. In its natural form, uranium ore can appear black, yellow, or green, depending on its mineral composition. While weakly radioactive, uranium poses significant risks if inhaled, ingested, or improperly handled, as it emits alpha radiation and is chemically toxic to the kidneys. The greatest dangers come from uranium dust, radon gas exposure, and improper waste disposal, which can lead to environmental contamination and health hazards like lung cancer. Shockingly, in this a recent video, allegedly from Zamfara mines, it can be seen and heard how people handle uranium, completely unaware of the grave risks involved. In the video, it can be heard that one person recording was telling another called Yushau in Hausa about the quantity of the metal available (8 to 10 kilograms), further exposing the dangerous ignorance surrounding its handling. This reckless exposure highlights the urgent need for government intervention. This further highlights why the authorities must manage and handle the mining crisis in those locations to avoid exposing people to dangerous gasses that would continue to damage their organs. NB: As of February 20, 2025, the market price of uranium is roughly $143 (₦214, 500) per kilogram. (Source:

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23,495 次观看 • 1 年前