🔴معرفی آزمون تافل هوم ادیشن، نحوه برگزاری آزمون و ویژگی های آن در لینک زیر
👇👇
https://b2n.ir/r76657
Join ➣ @BestIELTS ☜عضويت
www.bestielts.ir
👇👇
https://b2n.ir/r76657
Join ➣ @BestIELTS ☜عضويت
www.bestielts.ir
🔴انجام تست کوتاه سنجش گرامر از طریق لینک زیر
👇👇
https://bestielts.ir/grammar-quiz/
Join ➣ @BestIELTS ☜عضويت
www.bestielts.ir
👇👇
https://bestielts.ir/grammar-quiz/
Join ➣ @BestIELTS ☜عضويت
www.bestielts.ir
This media is not supported in your browser
VIEW IN TELEGRAM
🔴Can you solve the prisoner hat riddle?
#collaboration #memory #creativity #philosophy #TED_Ed #animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#collaboration #memory #creativity #philosophy #TED_Ed #animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
👍1
🔴Can you solve the prisoner hat riddle?
You and nine other individuals have been captured by super intelligent alien overlords. The aliens think humans look quite tasty, but their civilization forbids eating highly logical and cooperative beings. Unfortunately, they're not sure whether you qualify, so they decide to give you all a test. Through its universal translator, the alien guarding you tells you the following: You will be placed in a single-file line facing forward in size order so that each of you can see everyone lined up ahead of you. You will not be able to look behind you or step out of line. Each of you will have either a black or a white hat on your head assigned randomly, and I won't tell you how many of each color there are. When I say to begin, each of you must guess the color of your hat starting with the person in the back and moving up the line. And don't even try saying words other than black or white or signaling some other way, like intonation or volume; you'll all be eaten immediately. If at least nine of you guess correctly, you'll all be spared. You have five minutes to discuss and come up with a plan, and then I'll line you up, assign your hats, and we'll begin. Can you think of a strategy guaranteed to save everyone? Pause the video now to figure it out for yourself. Answer in: 3 Answer in: 2 Answer in: 1 The key is that the person at the back of the line who can see everyone else's hats can use the words "black" or "white" to communicate some coded information. So what meaning can be assigned to those words that will allow everyone else to deduce their hat colors? It can't be the total number of black or white hats. There are more than two possible values, but what does have two possible values is that number's parity, that is whether it's odd or even. So the solution is to agree that whoever goes first will, for example, say "black" if he sees an odd number of black hats and "white" if he sees an even number of black hats. Let's see how it would play out if the hats were distributed like this. The tallest captive sees three black hats in front of him, so he says "black," telling everyone else he sees an odd number of black hats. He gets his own hat color wrong, but that's okay since you're collectively allowed to have one wrong answer. Prisoner two also sees an odd number of black hats, so she knows hers is white, and answers correctly. Prisoner three sees an even number of black hats, so he knows that his must be one of the black hats the first two prisoners saw. Prisoner four hears that and knows that she should be looking for an even number of black hats since one was behind her. But she only sees one, so she deduces that her hat is also black. Prisoners five through nine are each looking for an odd number of black hats, which they see, so they figure out that their hats are white. Now it all comes down to you at the front of the line. If the ninth prisoner saw an odd number of black hats, that can only mean one thing. You'll find that this strategy works for any possible arrangement of the hats. The first prisoner has a 50% chance of giving a wrong answer about his own hat, but the parity information he conveys allows everyone else to guess theirs with absolute certainty. Each begins by expecting to see an odd or even number of hats of the specified color. If what they count doesn't match, that means their own hat is that color. And everytime this happens, the next person in line will switch the parity they expect to see. So that's it, you're free to go. It looks like these aliens will have to go hungry, or find some less logical organisms to abduct.
#collaboration #memory #creativity #philosophy #TED_Ed #animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
You and nine other individuals have been captured by super intelligent alien overlords. The aliens think humans look quite tasty, but their civilization forbids eating highly logical and cooperative beings. Unfortunately, they're not sure whether you qualify, so they decide to give you all a test. Through its universal translator, the alien guarding you tells you the following: You will be placed in a single-file line facing forward in size order so that each of you can see everyone lined up ahead of you. You will not be able to look behind you or step out of line. Each of you will have either a black or a white hat on your head assigned randomly, and I won't tell you how many of each color there are. When I say to begin, each of you must guess the color of your hat starting with the person in the back and moving up the line. And don't even try saying words other than black or white or signaling some other way, like intonation or volume; you'll all be eaten immediately. If at least nine of you guess correctly, you'll all be spared. You have five minutes to discuss and come up with a plan, and then I'll line you up, assign your hats, and we'll begin. Can you think of a strategy guaranteed to save everyone? Pause the video now to figure it out for yourself. Answer in: 3 Answer in: 2 Answer in: 1 The key is that the person at the back of the line who can see everyone else's hats can use the words "black" or "white" to communicate some coded information. So what meaning can be assigned to those words that will allow everyone else to deduce their hat colors? It can't be the total number of black or white hats. There are more than two possible values, but what does have two possible values is that number's parity, that is whether it's odd or even. So the solution is to agree that whoever goes first will, for example, say "black" if he sees an odd number of black hats and "white" if he sees an even number of black hats. Let's see how it would play out if the hats were distributed like this. The tallest captive sees three black hats in front of him, so he says "black," telling everyone else he sees an odd number of black hats. He gets his own hat color wrong, but that's okay since you're collectively allowed to have one wrong answer. Prisoner two also sees an odd number of black hats, so she knows hers is white, and answers correctly. Prisoner three sees an even number of black hats, so he knows that his must be one of the black hats the first two prisoners saw. Prisoner four hears that and knows that she should be looking for an even number of black hats since one was behind her. But she only sees one, so she deduces that her hat is also black. Prisoners five through nine are each looking for an odd number of black hats, which they see, so they figure out that their hats are white. Now it all comes down to you at the front of the line. If the ninth prisoner saw an odd number of black hats, that can only mean one thing. You'll find that this strategy works for any possible arrangement of the hats. The first prisoner has a 50% chance of giving a wrong answer about his own hat, but the parity information he conveys allows everyone else to guess theirs with absolute certainty. Each begins by expecting to see an odd or even number of hats of the specified color. If what they count doesn't match, that means their own hat is that color. And everytime this happens, the next person in line will switch the parity they expect to see. So that's it, you're free to go. It looks like these aliens will have to go hungry, or find some less logical organisms to abduct.
#collaboration #memory #creativity #philosophy #TED_Ed #animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
Media is too big
VIEW IN TELEGRAM
🔴What does the world's largest machine do?
#Education #Energy #TED_Ed #Natural_Resources #Animation #Electricity #Renewable_Energy
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#Education #Energy #TED_Ed #Natural_Resources #Animation #Electricity #Renewable_Energy
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
🔴What does the world's largest machine do?
On February 7th, 1967, Homer Loutzenheuser flipped a switch in Nebraska and realized a dream more than five decades in the making. The power grids of the United States joined together, forming one interconnected machine stretching coast to coast. Today, the US power grid is the world's largest machine. It contains more than 7,300 electricity-generating plants, linked by some 11 million kilometers of powerlines, transformers and substations.
Power grids span Earth’s continents, transmitting electricity around the clock. They’re massive feats of engineering— but their functioning depends on a delicate balance. Their components must always work in unison, maintain a constant frequency throughout the grid, and match energy supply with demand. If there's too much electricity in the system, you get unsafe power spikes that can overheat and damage equipment. Too little electricity and you get blackouts.
So, to strike this balance, power grid operators monitor the grid from sophisticated control centers. They forecast energy demand and adjust which power plants are active, signaling them to turn their output up or down to precisely meet current demand.
By considering factors like the availability and cost of energy resources, grid operators create a “dispatch curve,” which maps out the order in which energy sources will be used. The grid defaults to using energy from the start of the curve first. Usually, the resources are ordered by price. Those at the start tend to be renewables because they have much lower production costs. Some grids, like those in Iceland and Costa Rica, run on more than 98% clean energy. But most dispatch curves contain more of a mix of carbon-free and carbon-emitting energy sources. This means that where your electricity is coming from— and how clean it is— varies throughout the day— as often as every few minutes.
Take the state of Kansas. Despite having plentiful wind resources, it regularly relies on carbon-emitting power plants. This is because wind energy is especially plentiful at night. But, this is also when there’s lower demand. So, Kansas’ is wind energy is actually regularly disposed of to prevent excess electricity from damaging the grid. And comparable scenarios add up to a big problem worldwide. Thankfully, dependence on renewables is rising. But power grids are often unable to make full use of them.
Many simply weren't designed around intermittent energy sources and can't store large amounts of electricity. Researchers are experimenting with unique storage solutions. However, this will take time and substantial investment. But hope is not lost. We have the opportunity to work with our existing power grids in a new way: by shifting some of our energy use to the times when there’s clean electricity to spare. Leaning into this concept, called “load flexibility,” we can help flatten the peaks in demand, which will place less stress on the grid and reduce the need for non-renewables.
So researchers are developing automated emissions reduction technologies that tap into energy use data and ensure that devices get electricity from the grid at the cleanest times. In fact, smart devices like this already exist. So, how big an effect could they have? If smart technologies like air conditioners, water heaters, and electric vehicle chargers were implemented across the Texas power grid, the state’s emissions could decrease by around 20%. In other words, simply coordinating when certain devices tap into the grid could translate to 6 million fewer tons of carbon released into the atmosphere annually from Texas alone. Now, imagine what this could look like on a global scale.
#Education #Energy #TED_Ed #Natural_Resources #Animation #Electricity #Renewable_Energy
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
On February 7th, 1967, Homer Loutzenheuser flipped a switch in Nebraska and realized a dream more than five decades in the making. The power grids of the United States joined together, forming one interconnected machine stretching coast to coast. Today, the US power grid is the world's largest machine. It contains more than 7,300 electricity-generating plants, linked by some 11 million kilometers of powerlines, transformers and substations.
Power grids span Earth’s continents, transmitting electricity around the clock. They’re massive feats of engineering— but their functioning depends on a delicate balance. Their components must always work in unison, maintain a constant frequency throughout the grid, and match energy supply with demand. If there's too much electricity in the system, you get unsafe power spikes that can overheat and damage equipment. Too little electricity and you get blackouts.
So, to strike this balance, power grid operators monitor the grid from sophisticated control centers. They forecast energy demand and adjust which power plants are active, signaling them to turn their output up or down to precisely meet current demand.
By considering factors like the availability and cost of energy resources, grid operators create a “dispatch curve,” which maps out the order in which energy sources will be used. The grid defaults to using energy from the start of the curve first. Usually, the resources are ordered by price. Those at the start tend to be renewables because they have much lower production costs. Some grids, like those in Iceland and Costa Rica, run on more than 98% clean energy. But most dispatch curves contain more of a mix of carbon-free and carbon-emitting energy sources. This means that where your electricity is coming from— and how clean it is— varies throughout the day— as often as every few minutes.
Take the state of Kansas. Despite having plentiful wind resources, it regularly relies on carbon-emitting power plants. This is because wind energy is especially plentiful at night. But, this is also when there’s lower demand. So, Kansas’ is wind energy is actually regularly disposed of to prevent excess electricity from damaging the grid. And comparable scenarios add up to a big problem worldwide. Thankfully, dependence on renewables is rising. But power grids are often unable to make full use of them.
Many simply weren't designed around intermittent energy sources and can't store large amounts of electricity. Researchers are experimenting with unique storage solutions. However, this will take time and substantial investment. But hope is not lost. We have the opportunity to work with our existing power grids in a new way: by shifting some of our energy use to the times when there’s clean electricity to spare. Leaning into this concept, called “load flexibility,” we can help flatten the peaks in demand, which will place less stress on the grid and reduce the need for non-renewables.
So researchers are developing automated emissions reduction technologies that tap into energy use data and ensure that devices get electricity from the grid at the cleanest times. In fact, smart devices like this already exist. So, how big an effect could they have? If smart technologies like air conditioners, water heaters, and electric vehicle chargers were implemented across the Texas power grid, the state’s emissions could decrease by around 20%. In other words, simply coordinating when certain devices tap into the grid could translate to 6 million fewer tons of carbon released into the atmosphere annually from Texas alone. Now, imagine what this could look like on a global scale.
#Education #Energy #TED_Ed #Natural_Resources #Animation #Electricity #Renewable_Energy
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
💥مجموعه ای از تست های رایگان تعیین سطح زبان ویژه متقاضیان آیلتس، تافل در کلیه سطوح تنها در ۲۰ دقیقه در بخش های گرامر، واژگان، ریدینگ و کالوکیشن در لینک زیر
👇👇
https://b2n.ir/d52475
Join ➣ @BestIELTS ☜عضويت
www.bestielts.ir
👇👇
https://b2n.ir/d52475
Join ➣ @BestIELTS ☜عضويت
www.bestielts.ir
This media is not supported in your browser
VIEW IN TELEGRAM
🔴The 4 greatest threats to the survival of humanity
#Climate_Change #Science #Technology #Biotech #Education #Future #Humanity #Pandemic #TED_Ed #Animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#Climate_Change #Science #Technology #Biotech #Education #Future #Humanity #Pandemic #TED_Ed #Animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
🔴The 4 greatest threats to the survival of humanity
In January of 1995, Russia detected a nuclear missile headed its way. The alert went all the way to the president, who was deciding whether to strike back when another system contradicted the initial warning. What they thought was the first missile in a massive attack was actually a research rocket studying the Northern Lights. This incident happened after the end of the Cold War, but was nevertheless one of the closest calls we’ve had to igniting a global nuclear war.
With the invention of the atomic bomb, humanity gained the power to destroy itself for the first time in our history. Since then, our existential risk— risk of either extinction or the unrecoverable collapse of human civilization— has steadily increased. It’s well within our power to reduce this risk, but in order to do so, we have to understand which of our activities pose existential threats now, and which might in the future.
So far, our species has survived 2,000 centuries, each with some extinction risk from natural causes— asteroid impacts, supervolcanoes, and the like. Assessing existential risk is an inherently uncertain business because usually when we try to figure out how likely something is, we check how often it's happened before. But the complete destruction of humanity has never happened before. While there’s no perfect method to determine our risk from natural threats, experts estimate it’s about 1 in 10,000 per century.
Nuclear weapons were our first addition to that baseline. While there are many risks associated with nuclear weapons, the existential risk comes from the possibility of a global nuclear war that leads to a nuclear winter, where soot from burning cities blocks out the sun for years, causing the crops that humanity depends on to fail. We haven't had a nuclear war yet, but our track record is too short to tell if they’re inherently unlikely or we’ve simply been lucky. We also can’t say for sure whether a global nuclear war would cause a nuclear winter so severe it would pose an existential threat to humanity.
The next major addition to our existential risk was climate change. Like nuclear war, climate change could result in a lot of terrible scenarios that we should be working hard to avoid, but that would stop short of causing extinction or unrecoverable collapse. We expect a few degrees Celsius of warming, but can’t yet completely rule out 6 or even 10 degrees, which would cause a calamity of possibly unprecedented proportions. Even in this worst-case scenario, it’s not clear whether warming would pose a direct existential risk, but the disruption it would cause would likely make us more vulnerable to other existential risks.
The greatest risks may come from technologies that are still emerging. Take engineered pandemics. The biggest catastrophes in human history have been from pandemics. And biotechnology is enabling us to modify and create germs that could be much more deadly than naturally occurring ones. Such germs could cause pandemics through biowarfare and research accidents. Decreased costs of genome sequencing and modification, along with increased availability of potentially dangerous information like the published genomes of deadly viruses, also increase the number of people and groups who could potentially create such pathogens.
Another concern is unaligned AI. Most AI researchers think this will be the century where we develop artificial intelligence that surpasses human abilities across the board. If we cede this advantage, we place our future in the hands of the systems we create. Even if created solely with humanity’s best interests in mind, superintelligent AI could pose an existential risk if it isn’t perfectly aligned with human values— a task scientists are finding extremely difficult.
In January of 1995, Russia detected a nuclear missile headed its way. The alert went all the way to the president, who was deciding whether to strike back when another system contradicted the initial warning. What they thought was the first missile in a massive attack was actually a research rocket studying the Northern Lights. This incident happened after the end of the Cold War, but was nevertheless one of the closest calls we’ve had to igniting a global nuclear war.
With the invention of the atomic bomb, humanity gained the power to destroy itself for the first time in our history. Since then, our existential risk— risk of either extinction or the unrecoverable collapse of human civilization— has steadily increased. It’s well within our power to reduce this risk, but in order to do so, we have to understand which of our activities pose existential threats now, and which might in the future.
So far, our species has survived 2,000 centuries, each with some extinction risk from natural causes— asteroid impacts, supervolcanoes, and the like. Assessing existential risk is an inherently uncertain business because usually when we try to figure out how likely something is, we check how often it's happened before. But the complete destruction of humanity has never happened before. While there’s no perfect method to determine our risk from natural threats, experts estimate it’s about 1 in 10,000 per century.
Nuclear weapons were our first addition to that baseline. While there are many risks associated with nuclear weapons, the existential risk comes from the possibility of a global nuclear war that leads to a nuclear winter, where soot from burning cities blocks out the sun for years, causing the crops that humanity depends on to fail. We haven't had a nuclear war yet, but our track record is too short to tell if they’re inherently unlikely or we’ve simply been lucky. We also can’t say for sure whether a global nuclear war would cause a nuclear winter so severe it would pose an existential threat to humanity.
The next major addition to our existential risk was climate change. Like nuclear war, climate change could result in a lot of terrible scenarios that we should be working hard to avoid, but that would stop short of causing extinction or unrecoverable collapse. We expect a few degrees Celsius of warming, but can’t yet completely rule out 6 or even 10 degrees, which would cause a calamity of possibly unprecedented proportions. Even in this worst-case scenario, it’s not clear whether warming would pose a direct existential risk, but the disruption it would cause would likely make us more vulnerable to other existential risks.
The greatest risks may come from technologies that are still emerging. Take engineered pandemics. The biggest catastrophes in human history have been from pandemics. And biotechnology is enabling us to modify and create germs that could be much more deadly than naturally occurring ones. Such germs could cause pandemics through biowarfare and research accidents. Decreased costs of genome sequencing and modification, along with increased availability of potentially dangerous information like the published genomes of deadly viruses, also increase the number of people and groups who could potentially create such pathogens.
Another concern is unaligned AI. Most AI researchers think this will be the century where we develop artificial intelligence that surpasses human abilities across the board. If we cede this advantage, we place our future in the hands of the systems we create. Even if created solely with humanity’s best interests in mind, superintelligent AI could pose an existential risk if it isn’t perfectly aligned with human values— a task scientists are finding extremely difficult.
Based on what we know at this point, some experts estimate the anthropogenic existential risk is more than 100 times higher than the background rate of natural risk. But these odds depend heavily on human choices. Because most of the risk is from human action, and it’s within human control. If we treat safeguarding humanity's future as the defining issue of our time, we can reduce this risk. Whether humanity fulfils its potential— or not— is in our hands.
#Climate_Change #Science #Technology #Biotech #Education #Future #Humanity #Pandemic #TED_Ed #Animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#Climate_Change #Science #Technology #Biotech #Education #Future #Humanity #Pandemic #TED_Ed #Animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
Media is too big
VIEW IN TELEGRAM
🔴Why is it so hard to cure the common cold?
#Education #Disease #Health #Health_Care #Medicine #Illness #Vaccines #Virus #Medical_Research #TED_Ed #Animation #Human_Body #Coronavirus
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#Education #Disease #Health #Health_Care #Medicine #Illness #Vaccines #Virus #Medical_Research #TED_Ed #Animation #Human_Body #Coronavirus
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
🔴Why is it so hard to cure the common cold?
In 2000, a company called ViroPharma ran clinical trials of pleconaril, a new pill designed to treat the common cold. In many patients, the pill helped. But in 7 of them, just a few days into the treatment, researchers found mutated virus variants that were almost completely resistant to pleconaril.
Viruses are always mutating, but this one mutated so quickly that it managed to outmaneuver years of research and development in just a few days.
If you didn't have an immune system and caught a cold, the infection would quickly spread deep into your lungs. Rampant viral replication would destroy tissue there, until your lungs couldn’t supply your body with enough oxygen and you’d asphyxiate.
Unfortunately, for millions of people around the world who live with a less-than-fully-functional immune system or who are on immunosuppressant drugs, this is a real risk: “minor” infections can turn serious or even deadly.
But if you're fortunate enough to have a fully functional immune system, a cold will probably give you a few relatively mild symptoms. On average, adults catch more than 150 colds throughout their lives. And despite the fact that the symptoms are similar, the cause could be different each time
Common colds are caused by at least 8 different families of virus, each of which can have its own species and subtypes.
How can so many different viruses cause the same illness? Well, viruses can only invade our bodies in a few ways: one is to come in on a breath. We have to breathe, so our immune system sets up a bunch of frontline defenses and these are actually what produce many of the symptoms of a cold. Your mucus-y, dripping nose is your immune system trapping and flushing out virus. Your fever is your immune system raising your body temperature to slow down viral replication. And your inflamed, well, everything, that’s your immune system widening your blood vessels and recruiting its white blood cell army to help kill the virus.
So, if the common cold is caused by many different viruses, is a cure even possible?
Here’s one fact in our favor: a single family of viruses causes 30 to 50% of all colds: rhinovirus. If we could eliminate all rhinovirus infections, we’d be a long way towards curing the common cold.
There are two main ways to fight a virus: vaccines and antiviral drugs.
The first attempt to create a rhinovirus vaccine was a success— but a short-lived one. In 1957, William Price vaccinated 50 kids with inactivated rhinovirus and gave 50 others a placebo. Soon afterwards, a rhinovirus outbreak spread throughout the kids. In the vaccinated group, only 3 got sick. In the placebo group, 23 did— almost 8 times as many. And despite the small numbers, this was promising: the immune systems of vaccinated kids were successfully recognizing and responding to rhinovirus.
But later trials of the vaccine showed no protection at all— none. This wasn’t Price’s fault— no one at the time knew that rhinovirus had multiple subtypes. Price’s vaccine, for reasons we don’t fully understand, didn't provide broad protection, meaning it was only effective against one or maybe a few subtypes of rhinovirus— out of 169 subtypes and counting.
Sometimes, when we make a vaccine, we get lucky. The mRNA COVID vaccines, for example, effectively protect us against severe disease and death across the original virus and variants too.
But we have yet to create a broadly protective vaccine against rhinovirus, or any other virus that causes the common cold.
Okay, what about antiviral drugs?
Viruses hijack human cellular machinery to replicate and spread, so it’s hard to make a molecule that’s toxic to the virus without also being toxic to the human. And even if you manage to do that, the virus could mutate out of reach of the drug.
In 2000, a company called ViroPharma ran clinical trials of pleconaril, a new pill designed to treat the common cold. In many patients, the pill helped. But in 7 of them, just a few days into the treatment, researchers found mutated virus variants that were almost completely resistant to pleconaril.
Viruses are always mutating, but this one mutated so quickly that it managed to outmaneuver years of research and development in just a few days.
If you didn't have an immune system and caught a cold, the infection would quickly spread deep into your lungs. Rampant viral replication would destroy tissue there, until your lungs couldn’t supply your body with enough oxygen and you’d asphyxiate.
Unfortunately, for millions of people around the world who live with a less-than-fully-functional immune system or who are on immunosuppressant drugs, this is a real risk: “minor” infections can turn serious or even deadly.
But if you're fortunate enough to have a fully functional immune system, a cold will probably give you a few relatively mild symptoms. On average, adults catch more than 150 colds throughout their lives. And despite the fact that the symptoms are similar, the cause could be different each time
Common colds are caused by at least 8 different families of virus, each of which can have its own species and subtypes.
How can so many different viruses cause the same illness? Well, viruses can only invade our bodies in a few ways: one is to come in on a breath. We have to breathe, so our immune system sets up a bunch of frontline defenses and these are actually what produce many of the symptoms of a cold. Your mucus-y, dripping nose is your immune system trapping and flushing out virus. Your fever is your immune system raising your body temperature to slow down viral replication. And your inflamed, well, everything, that’s your immune system widening your blood vessels and recruiting its white blood cell army to help kill the virus.
So, if the common cold is caused by many different viruses, is a cure even possible?
Here’s one fact in our favor: a single family of viruses causes 30 to 50% of all colds: rhinovirus. If we could eliminate all rhinovirus infections, we’d be a long way towards curing the common cold.
There are two main ways to fight a virus: vaccines and antiviral drugs.
The first attempt to create a rhinovirus vaccine was a success— but a short-lived one. In 1957, William Price vaccinated 50 kids with inactivated rhinovirus and gave 50 others a placebo. Soon afterwards, a rhinovirus outbreak spread throughout the kids. In the vaccinated group, only 3 got sick. In the placebo group, 23 did— almost 8 times as many. And despite the small numbers, this was promising: the immune systems of vaccinated kids were successfully recognizing and responding to rhinovirus.
But later trials of the vaccine showed no protection at all— none. This wasn’t Price’s fault— no one at the time knew that rhinovirus had multiple subtypes. Price’s vaccine, for reasons we don’t fully understand, didn't provide broad protection, meaning it was only effective against one or maybe a few subtypes of rhinovirus— out of 169 subtypes and counting.
Sometimes, when we make a vaccine, we get lucky. The mRNA COVID vaccines, for example, effectively protect us against severe disease and death across the original virus and variants too.
But we have yet to create a broadly protective vaccine against rhinovirus, or any other virus that causes the common cold.
Okay, what about antiviral drugs?
Viruses hijack human cellular machinery to replicate and spread, so it’s hard to make a molecule that’s toxic to the virus without also being toxic to the human. And even if you manage to do that, the virus could mutate out of reach of the drug.
Viruses are slippery beasts. We have, though, had some incredible successes: we eradicated smallpox thanks to an effective vaccine, the fact that it can’t hide out in other species, and its relatively low mutation rate. HIV, on the other hand, mutates so quickly that in an untreated individual, every possible single-letter mutation in the virus’s genetic code could, in theory, be produced in a single day.
Despite trying for decades, we still don’t have a vaccine. But we do have an effective cocktail of HIV drugs that the virus can’t easily mutate away from.
Unfortunately, we are stuck with colds for now. But the last few decades have featured some entirely game-changing medical breakthroughs, like mRNA vaccines and CRISPR. CRISPR could be particularly promising as an antiviral agent, because it originally evolved in bacteria as an immune defense against viruses. In fact, early in the COVID-19 pandemic, a research team showed that a CRISPR system could degrade coronavirus and influenza genomes in our lung cells. They called their system prophylactic antiviral CRISPR in human cells.
#Education #Disease #Health #Health_Care #Medicine #Illness #Vaccines #Virus #Medical_Research #TED_Ed #Animation #Human_Body #Coronavirus
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
Despite trying for decades, we still don’t have a vaccine. But we do have an effective cocktail of HIV drugs that the virus can’t easily mutate away from.
Unfortunately, we are stuck with colds for now. But the last few decades have featured some entirely game-changing medical breakthroughs, like mRNA vaccines and CRISPR. CRISPR could be particularly promising as an antiviral agent, because it originally evolved in bacteria as an immune defense against viruses. In fact, early in the COVID-19 pandemic, a research team showed that a CRISPR system could degrade coronavirus and influenza genomes in our lung cells. They called their system prophylactic antiviral CRISPR in human cells.
#Education #Disease #Health #Health_Care #Medicine #Illness #Vaccines #Virus #Medical_Research #TED_Ed #Animation #Human_Body #Coronavirus
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
🔴تست رایگان تعیین سطح ریدینگ آیلتس با توجه به درخواست های متقاضیان در لینک زیر👇👇
https://b2n.ir/h77334
Join ➣ @BestIELTS
www.bestielts.ir
https://b2n.ir/h77334
Join ➣ @BestIELTS
www.bestielts.ir
Media is too big
VIEW IN TELEGRAM
🔴What's the smartest age?
#Memory #Education #Aging #Brain #TED_Ed #Animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#Memory #Education #Aging #Brain #TED_Ed #Animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
👍1
🔴What's the smartest age?
What is the smartest age? Perhaps a day of friendly competition will lead us to the answer.
Tomorrow’s the annual Brain Clash— ten teams of two competing in a decathlon of mental challenges, trivia competitions, and puzzles. I’ve been training all year. I’ll need to pick the smartest, most capable teammate. I’ve narrowed down the roster.
First we have Gabriela. She may only be 8, but don’t underestimate her! She’s fluent in two languages and is the ultimate outside-the-box thinker.
Then there’s Ama. She can recite 100 digits of pi, designs satellites for a living, and bakes a perfect soufflé.
Or I could go with Mr. Taylor. He’s the best chess player in the neighborhood, not to mention he’s competed in over 20 Brain Clashes and is a five-time champion! I’m not sure who to pick! Who’s the smartest?
Which of these teammates should Amir choose for tomorrow's contest and why? Of course, it depends.
While intelligence is often associated with things like IQ tests, these assessments fail to capture the scope and depth of a person’s varied abilities. So instead, we’ll break down the idea of “smart” into categories like creativity, memory, and learning and explore when the brain’s best at each of them.
Let's start at the very beginning. In the first few years of life, your brain undergoes incredible rapid growth, called synaptogenesis, where more than 1 million new neural connections are formed every second.
As the brain develops, it goes through a pruning process. Based on your experience and environment, used connections are strengthened and unused connections are removed. Frequently used neuronal pathways are myelinated, wrapped in a layer of insulation, allowing information to travel faster. This creates a more efficient, fine-tuned brain. But this brain remodeling happens within and between brain regions at different times, allowing different skills to flourish at different ages.
For example, in childhood, brain regions involved in language learning develop quickly, which is why many children can learn and master multiple languages. Yet the prefrontal cortex, a brain region responsible for cognitive control and inhibition, is slower to develop. As a result, some young children may struggle with strategic games, such as chess or checkers, which require constant concentration, planning, and abstract thought. At the same time, children tend to be more flexible, exploration-based learners. They often use more creative approaches when finding solutions to riddles and are, on average, less afraid to make mistakes.
But adults have their own unique set of abilities. Adults benefit from a well-developed prefrontal cortex, allowing them to better execute skills that require learning, focus, and memory, making them quick and efficient puzzle solvers or crossword masters.
Late in adulthood, these same skills may decline as the brain’s memory center, known as the hippocampus, shrinks. But there’s a reason for the phrase “older and wiser.” After a lifetime of learning, older adults have more knowledge to recall and utilize, making them excellent trivia partners.
Other factors that Amir should consider are his own strengths. As an adolescent, the prefrontal cortical regions of your brain are more developed than in childhood. This allows you to better navigate logic and math puzzles. Simultaneously, deep inside the brain, regions that are important in motivation and reward are developing even faster, driving teenagers like Amir to be curious and adventurous learners.
In many ways, you can think of the teenager as a jack-of-all-trades, with brains wired to seek out new experiences and learn quickly. You’re at a dynamic stage, where the choices you make and the skills you focus on can actually guide the development of your brain.
What is the smartest age? Perhaps a day of friendly competition will lead us to the answer.
Tomorrow’s the annual Brain Clash— ten teams of two competing in a decathlon of mental challenges, trivia competitions, and puzzles. I’ve been training all year. I’ll need to pick the smartest, most capable teammate. I’ve narrowed down the roster.
First we have Gabriela. She may only be 8, but don’t underestimate her! She’s fluent in two languages and is the ultimate outside-the-box thinker.
Then there’s Ama. She can recite 100 digits of pi, designs satellites for a living, and bakes a perfect soufflé.
Or I could go with Mr. Taylor. He’s the best chess player in the neighborhood, not to mention he’s competed in over 20 Brain Clashes and is a five-time champion! I’m not sure who to pick! Who’s the smartest?
Which of these teammates should Amir choose for tomorrow's contest and why? Of course, it depends.
While intelligence is often associated with things like IQ tests, these assessments fail to capture the scope and depth of a person’s varied abilities. So instead, we’ll break down the idea of “smart” into categories like creativity, memory, and learning and explore when the brain’s best at each of them.
Let's start at the very beginning. In the first few years of life, your brain undergoes incredible rapid growth, called synaptogenesis, where more than 1 million new neural connections are formed every second.
As the brain develops, it goes through a pruning process. Based on your experience and environment, used connections are strengthened and unused connections are removed. Frequently used neuronal pathways are myelinated, wrapped in a layer of insulation, allowing information to travel faster. This creates a more efficient, fine-tuned brain. But this brain remodeling happens within and between brain regions at different times, allowing different skills to flourish at different ages.
For example, in childhood, brain regions involved in language learning develop quickly, which is why many children can learn and master multiple languages. Yet the prefrontal cortex, a brain region responsible for cognitive control and inhibition, is slower to develop. As a result, some young children may struggle with strategic games, such as chess or checkers, which require constant concentration, planning, and abstract thought. At the same time, children tend to be more flexible, exploration-based learners. They often use more creative approaches when finding solutions to riddles and are, on average, less afraid to make mistakes.
But adults have their own unique set of abilities. Adults benefit from a well-developed prefrontal cortex, allowing them to better execute skills that require learning, focus, and memory, making them quick and efficient puzzle solvers or crossword masters.
Late in adulthood, these same skills may decline as the brain’s memory center, known as the hippocampus, shrinks. But there’s a reason for the phrase “older and wiser.” After a lifetime of learning, older adults have more knowledge to recall and utilize, making them excellent trivia partners.
Other factors that Amir should consider are his own strengths. As an adolescent, the prefrontal cortical regions of your brain are more developed than in childhood. This allows you to better navigate logic and math puzzles. Simultaneously, deep inside the brain, regions that are important in motivation and reward are developing even faster, driving teenagers like Amir to be curious and adventurous learners.
In many ways, you can think of the teenager as a jack-of-all-trades, with brains wired to seek out new experiences and learn quickly. You’re at a dynamic stage, where the choices you make and the skills you focus on can actually guide the development of your brain.
So, what’s the smartest age? There’s no single answer. It’s 8, 16, 25, 65, and everything in between; our brains have adapted to prioritize different skills at various ages to meet that stage of life’s challenges and demands. So no matter who Amir picks, having an age-diverse team is a good strategy.
#Memory #Education #Aging #Brain #TED_Ed #Animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#Memory #Education #Aging #Brain #TED_Ed #Animation
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
👍1
🔴🔴پکیج رایگان نکات مهم و کاربردی گرامر در دو سطح متوسط و پیشرفته برای داوطلبین کلیه آزمون های بین المللی سنجش زبان در لینک زیر👇👇
https://b2n.ir/f73846
Join ➣ @BestIELTS ☜عضويت
www.bestielts.ir
https://b2n.ir/f73846
Join ➣ @BestIELTS ☜عضويت
www.bestielts.ir
Media is too big
VIEW IN TELEGRAM
🔴Amazon's commitment to run on 100-percent renewable energy
#Climate_Change #Environment #Sustainability #BusinessEnergy #Renewable_Energy
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#Climate_Change #Environment #Sustainability #BusinessEnergy #Renewable_Energy
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
🔴Amazon's commitment to run on 100-percent renewable energy
It sounds simple, just power your business with 100 percent renewable energy. But the detail that goes in and the industry expertise that's required to really understand not just how much energy you're consuming across different parts of your business, but also what's the best and most cost-effective way to drive new wind and solar to the grids around the world. It's complicated, and not everybody has the opportunity to build an internal team of energy experts. It really comes back to the opportunity to partner.
When you take a step back and think about Amazon as a company, it's a complicated place. We operate data centers, distribution centers, warehouses, commercial offices, grocery stores, and all of these different types of operations have a different set of challenges that we're trying to tackle.
We set this goal to get to 100 percent renewable energy by 2030. We started off with questions like, “How much energy did we use in India last year, or last month, or yesterday?” Understanding our usage across time and across geographies, and then mapping that against where are the available solar and wind projects that we could possibly invest in and then figure out where can we be a catalyst to really drive new clean energy to the grids where we operate. We realized very quickly that we cannot go at this alone.
We needed to galvanize collective action across the entire economy, and that’s why we launched The Climate Pledge which is really just that, it’s a pledge and a commitment to get to net zero in alignment with climate science, but an invitation to partner and a collective call to action for other companies to take part in this journey with us.
So when we set out our second headquarters location in Arlington, Virginia, we tried to think about how are we going to power this new campus with 100 percent renewable energy. We got to know Arlington County and realized they also had a commitment to power their government buildings, as well as the entire community, with 100 percent renewable energy over time. So that instant partnership allowed us to come together and say, “What are some cool options that we can explore together to bring new renewable energy to Arlington?”
We took a step back to evaluate how much power will this campus consume? How much power will our local Whole Foods stores, our distribution center stores consume? We were able to add that all up and then talk to the county and ask them the exact same questions. How much power do you need to achieve your clean energy goals? And so we combined those numbers and really came to Dominion, the local utility provider, with the need of basically a 120-megawatt solar farm [to] meet all of our needs. We were able to strike an agreement that would allow us to bring that 120-megawatt solar farm online that would eventually feed the grids that feed government buildings, Amazon stores, as well as our new campus in Arlington.
When we started our journey, we were at 42 percent renewable energy in 2019. And fast forward to today, we're powered by 85 percent renewable energy across the world. We have a chance to accelerate that commitment to get to 100 percent renewable energy from 2030 down to 2025.
We have more work to do, but I think the proof points we have with renewable energy give us a blueprint on how we can attack other parts of the climate crisis yet to be solved. How do we decarbonize concrete in our buildings? How do we think about aviation from a zero-carbon perspective? How do we know what our buildings consume, how do we know where we need to get to to hit our goals?
It sounds simple, just power your business with 100 percent renewable energy. But the detail that goes in and the industry expertise that's required to really understand not just how much energy you're consuming across different parts of your business, but also what's the best and most cost-effective way to drive new wind and solar to the grids around the world. It's complicated, and not everybody has the opportunity to build an internal team of energy experts. It really comes back to the opportunity to partner.
When you take a step back and think about Amazon as a company, it's a complicated place. We operate data centers, distribution centers, warehouses, commercial offices, grocery stores, and all of these different types of operations have a different set of challenges that we're trying to tackle.
We set this goal to get to 100 percent renewable energy by 2030. We started off with questions like, “How much energy did we use in India last year, or last month, or yesterday?” Understanding our usage across time and across geographies, and then mapping that against where are the available solar and wind projects that we could possibly invest in and then figure out where can we be a catalyst to really drive new clean energy to the grids where we operate. We realized very quickly that we cannot go at this alone.
We needed to galvanize collective action across the entire economy, and that’s why we launched The Climate Pledge which is really just that, it’s a pledge and a commitment to get to net zero in alignment with climate science, but an invitation to partner and a collective call to action for other companies to take part in this journey with us.
So when we set out our second headquarters location in Arlington, Virginia, we tried to think about how are we going to power this new campus with 100 percent renewable energy. We got to know Arlington County and realized they also had a commitment to power their government buildings, as well as the entire community, with 100 percent renewable energy over time. So that instant partnership allowed us to come together and say, “What are some cool options that we can explore together to bring new renewable energy to Arlington?”
We took a step back to evaluate how much power will this campus consume? How much power will our local Whole Foods stores, our distribution center stores consume? We were able to add that all up and then talk to the county and ask them the exact same questions. How much power do you need to achieve your clean energy goals? And so we combined those numbers and really came to Dominion, the local utility provider, with the need of basically a 120-megawatt solar farm [to] meet all of our needs. We were able to strike an agreement that would allow us to bring that 120-megawatt solar farm online that would eventually feed the grids that feed government buildings, Amazon stores, as well as our new campus in Arlington.
When we started our journey, we were at 42 percent renewable energy in 2019. And fast forward to today, we're powered by 85 percent renewable energy across the world. We have a chance to accelerate that commitment to get to 100 percent renewable energy from 2030 down to 2025.
We have more work to do, but I think the proof points we have with renewable energy give us a blueprint on how we can attack other parts of the climate crisis yet to be solved. How do we decarbonize concrete in our buildings? How do we think about aviation from a zero-carbon perspective? How do we know what our buildings consume, how do we know where we need to get to to hit our goals?
Amazon wants to get to net zero because we don't have an option. The climate science is clear. We need partnerships to drive change at scale that's really going to drive carbon out of our global economy. And that was really the spirit of The Climate Pledge and a call to action to solve the climate crisis.
#Climate_Change #Environment #Sustainability #BusinessEnergy #Renewable_Energy
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜
#Climate_Change #Environment #Sustainability #BusinessEnergy #Renewable_Energy
🎙Join ➣ @TEDTalksLearning ☜
🎙Join ➣ @TEDTalksLearning ☜